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1
Gratao, Ana Angélica. "Impaired fertility in transgenic mice overexpressing betacellulin". [S.l.] : [s.n.], 2007. http://edoc.ub.uni-muenchen.de/archive/00006575.
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Gratao, Ana Angelica. "Impaired Fertility in Transgenic Mice Overexpressing Betacellulin". Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-65751.
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Byers, Shannon L. "Use of Inbred Strains of Mice to Study the Genetics and Biology of Sperm Function". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/ByersSL2006.pdf.
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Suzuki, Taichi A. "Speciation and Reduced Hybrid Female Fertility in House Mice". Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/202701.
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I asked whether there is female sterility in hybrid offspring of Mus musculus domesticus and M. m. musculus using two wild derived inbred strains representing each subspecies. I evaluated F1 hybrid female fertility by crossing F1 females to a tester male and comparing multiple reproductive parameters between intra-subspecific controls and inter-subspecific hybrids. Hybrid females had smaller litter size, reduced embryo survival, fewer ovulations, and fewer small follicles relative to controls. Significant variation in reproductive parameters was seen among different genotypes. Genes contributing to hybrid female infertility are polymorphic within subspecies. Differences in reproductive phenotypes in F1's of reciprocal crosses suggest that female subfertility may be due to either cyto-nuclear incompatibility or to imprinting. These findings suggest a greater complexity in hybrid sterility than has been previously appreciated and highlight the potential importance of hybrid female sterility in the early stages of speciation.
5
Everett, Clare Alexandra. "Robertsonian translocations and their effect on the fertility of mice". Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357568.
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Yaeram, Jakrit. "The effect of whole body heating on testis morphology and fertility of male mice". Title page, table of contents and summary only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phj259.pdf.
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Kongmanas, Kessiri. "Significance of sulfogalactosylglycerolipid in male fertility: Studies using Cgt heterozygous mice". Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/27996.
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Sulfogalactosylglycerolipid (SGG) is a sulfoglycolipid present specifically at a substantial level in mammalian male germ cells. It has been shown to function as an adhesion molecule important for sperm-egg interaction and a structural lipid involved in formation of sperm lipid rafts during capacitation in vitro. Due to the unique characteristics and functions, SGG can potentially serve as a biomarker for sperm fertility as well as a target for development of a non-hormonal contraceptive. To confirm the in vivo roles of SGG, we sought for transgenic mice with reduced amounts of sperm SGG. Cgt knockout male mice, transgenetically deficient in UDP-galactose:ceramide galactosyltransferase (CGT), an enzyme involved in SGG synthesis, are infertile due to spermatogenesis disruption. However, the Cgt+/- males can still produce sperm and sire offspring. We hypothesized that Cgt+/- males, expected to have reduced SGG amounts, would have compromised fertilizing ability and could serve as in vivo models for studying roles of SGG in fertilization and spermatogenesis. Unexpectedly, our results revealed that Cgt+/- males exhibited unimpaired spermatogenesis and fecundity. Moreover, the levels of SGG as well as lipid profiles of sperm and testes of Cgt+/- mice were similar to those of the wild type, suggesting that compensatory mechanisms must have occurred to maintain SGG levels in the Cgt+/- mice. Although these results revealed that Cgt+/- mice could not be used as the animal models, they implicated significance of normal testis and sperm SGG levels in maintaining normal spermatogenesis and fertility. The possible compensatory mechanisms regulating SGG levels were further investigated in Cgt+/- mice. As expected, only half of Cgt mRNA expression level of the wild type was transcribed in the Cgt+/- testes; however, testicular CGT polypeptides as well as their enzymatic activities in the Cgt+/- mice were found at a comparable level to those of the wild type. On the other hand, no change was found in terms of mRNA levels, polypeptide levels or enzymatic activities of arylsulfatase A (ASA), the enzyme responsible for SGG degradation in the testis. In conclusion, the compensatory mechanisms for SGG level adjustment in Cgt +/- mice occurred through the biosynthetic pathway, rather than the degradation pathway, by increasing the CGT polypeptide expression level. Therefore, identification of specific spermatogenic cell stages, contributing to normal expression levels of CGT and SGG in the Cgt+/- testes warrants further studies, as these studies should provide useful information regarding CGT and SGG importance during male germ cell development. In addition, a new approach to produce the animal models that can produce sperm with reduced SGG levels should be attempted. The RNA interference (RNAi) techniques may be tried to achieve this goal.
8
Vidarsson, Hilmar. "Foxi 1, an important gene for hearing, kidney function and male fertility /". Göteborg : Institute of Biomedicine, Dept. of Medical Genetics, Sahlgrenska Academy, Göteborg University, 2007. http://hdl.handle.net/2077/4727.
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Soler, David C. "The PP1 gamma isoforms restore spermatogenesis but not fertility in PP1 gamma null mice". [Kent, Ohio] : Kent State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1259087463.
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Thesis (Ph.D.)--Kent State University, 2009.Title from PDF t.p. (viewed May 17, 2010). Advisor: Srinivasan Vijayaraghavan. Keywords: sperm; spermatogenesis; PP1gamma2; PP1gamma1; mice; transgene. Includes bibliographical references (p. 102-123).
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Chow, Wang-ngai. "A study on the in vivo and in vitro embryotrophic effect of complement-3 (C3)". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39707532.
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Chow, Wang-ngai, e 周弘毅. "A study on the in vivo and in vitro embryotrophic effect ofcomplement-3 (C3)". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39707532.
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Wilson, Gabrielle. "The role of the parkin co-regulated gene (PACRG) in male fertility /". Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/5806.
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Thesis (Ph.D.)--University of Melbourne, Dept. of Paediatrics, The Bruce Lefroy Centre for Genetic Health Research, The Murdoch Childrens Research Institute, 2009.Typescript. Includes bibliographical references (leaves 183-207)
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Jiang, Qingkui [Verfasser]. "Effect of metabolic syndrome on fertility of male type 2 diabetic mice / Qingkui Jiang". Gießen : Universitätsbibliothek, 2017. http://d-nb.info/1141574624/34.
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Robertson, Kirsten 1975. "The reproductive phenotype of the male aromatase knockout mouse". Monash University, Dept. of Biochemistry and Molecular Biology, 2001. http://arrow.monash.edu.au/hdl/1959.1/8444.
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Ji, Min-Young. "Effect of protopanaxatriol saponin (PT) on spermatic stem cell survival and fertility of the busulfan treated mice". Kyoto University, 2007. http://hdl.handle.net/2433/136551.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第13133号
農博第1638号
新制||農||943(附属図書館)
学位論文||H19||N4259(農学部図書室)
UT51-2007-H406
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 今井 裕, 教授 久米 新一, 教授 廣岡 博之
学位規則第4条第1項該当
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Proffitt, Melissa. "Natural Variation in Fertility and GnRH Neurons in a Wild, Natural Population of White-Footed Mice, Peromyscus leucopus". W&M ScholarWorks, 2014. https://scholarworks.wm.edu/etd/1539626952.
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Vance, Lindsay Marie Rasmussen, e Lindsay Marie Rasmussen Vance. "Effects of Exposure to the Phthalate Substitute Acetyl Tributyl Citrate in Female CD-1 Mice". Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/620663.
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Some plasticizers are endocrine-disrupting chemicals that cause reproductive toxicity in both males and females. Several chemicals already approved by the Food and Drug Administration have been proposed as substitutes for some of these plasticizers, one example is acetyl tributyl citrate (ATBC). However, no studies have tested whether ATBC causes direct toxicity to the ovary. Ovarian antral follicles are essential for female fertility because they are the major producers of ovarian steroids and are the only follicle type that can ovulate in response to gonadotropin stimulation. Previous studies have used in-vitro ovarian follicle culture as a screening tool to demonstrate that EDCs can cause direct ovarian toxicity. Therefore, we designed this study to test whether exposure to in vitro treatment with ATBC causes ovarian toxicity in CD-1 mice. We mechanically isolated antral follicles from the ovaries of adult CD-1 mice (35-39 days old) and individually exposed them (n=5 cultures with n≥8 follicles per treatment) to supplemented media alone (NT), dimethyl sulfoxide (DMSO, vehicle for ATBC), and ATBC (0.001-100 µg/mL) for 24-72 h. Follicle growth and survival were monitored by measuring follicle diameter and cytotoxicity (compromised membrane integrity; CellTox Green) every 24 h, and assessing number of metabolically active cells (ATP concentration; Promega CellTiterGlo) at the end time point. The DNA synthesis inhibitor hydroxyurea (HU, 100 mM) was used as a positive control for the viability assays. Exposure to ATBC did not affect the ability of antral follicles to increase their diameter over time at all concentrations tested. When stratified by growth pattern, there was not a significant difference in the proportion of follicles growing normally, growing slowly, or not growing following ATBC exposure at all concentrations tested. ATBC treatment did not cause compromised membrane integrity and did not inhibit ATP production at any of the concentrations tested. The positive control, HU, inhibited follicle growth (24-72 h), decreased follicle cell membrane integrity (72 h), and inhibited ATP production (24-72 h). The purpose of this experiment is to evaluate the effects of oral exposure to ATBC in female CD-1 mice. For the in vivo experiments, the female mice (n=22; PND 81) were randomly divided into treatment groups and dosed according to daily body weight with one of the following treatments: corn oil (vehicle, n=7), 5 mg/kg/day ATBC (n=8), or 10 mg/kg/day (n=7) ATBC for 15 consecutive days. Vaginal smears were performed and analyzed daily to measure any change in estrous cyclicity. After the 15th day of dosing the female mice were introduced into an individually housed proven breeder male’s cage. Daily body weight measurements continued and plug checks were performed every morning. Pregnancy and time to conception data did not statistically differ from the vehicle (oil) for all ATBC treatments (days to conception: vehicle 2.43 ± 0.65, 5 mg/kg/day ATBC 2 ± 0.33, 10 mg/kg/day ATBC 2.5 ± 0.22; gestation length: vehicle 19.71 ± 0.18, 5 mg/kg/day ATBC 20 ± 0.19, 10 mg/kg/day ATBC 20 ± 0.00). On the day of parturition the dams and pups were sacrificed; organ weight and gross morphology data was collected for: uterus, kidneys, adrenals, spleen, liver, and ovaries. The data analyzed includes: estrous cyclicity, pre-dosing body weight % gain, dosing body weight % gain, pregnant body weight % gain, organ weight, gestation length, litter size (live vs. dead), litter weight, implantation sites, time to conception, and pup sex ratio. Interestingly, there was an increase in spleen weight at the 5 mg/kg/day treatment when compared to vehicle control-treated spleen weights (spleen weight, Oil: n=7; 5 mg/kg ATBC: n= 8). Treatment with 5 mg/kg/day ATBC caused a significant decrease in average estrous cycle length in days compared to the pre-dosing average estrous cycle length. Animals exposed orally to 10 mg/kg/day ATBC showed a significant decrease in total follicle number (10 mg/kg/day ATBC, 313 ± 20.37) when compared to vehicle (oil) treated mice (vehicle, 433.71 ± 34.85). Also treatment with 10 mg/kg/day ATBC resulted in significant reduction in secondary (101.67 ± 5.7) and late antral (4.17 ± 1.45) follicle numbers when compared to the vehicle-treated mice (secondary follicles: 141.14 ± 14.79, late antral follicles: 7.00 ± 1.54). ATBC treatment with 10 mg/kg/day showed a significantly decreased mean body weight percent gain during pregnancy on days 3, 5, and 14 when compared to animals treated with vehicle (oil), while animals treated with 5 mg/kg/day ATBC showed a significant decrease in weight gained on only day 13 when compared to the vehicle (oil). These novel findings show that ATBC could disrupt ovarian function in mice when exposed to low-dose ATBC.
18
Newhall, Kathryn Jean. "The utilization of genetic mouse models to study protein kinase A signaling in body weight regulation and fertility /". Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6285.
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Dietzel, Eileen [Verfasser]. "The biological role of fetuin-B : inhibition of zona pellucida hardening and preservation of female fertility in mice / Eileen Dietzel". Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2015. http://d-nb.info/1066813701/34.
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Sinha, Nilam. "Mammal specific protein phosphatase isoform, PPP1CC2, is essential for sperm function and male fertility". Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1334525491.
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Pelz, Laura [Verfasser]. "The cell adhesion molecule BT-IgSF is essential for a functional blood-testis barrier and male fertility in mice / Laura Pelz". Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1154766675/34.
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Dasgupta, Shuvalaxmi Purnendu. "PP1 Gamma 2 LEVELS ARE HIGHLY REGULATED IN TESTIS TO ENSURE NORMAL SPERMATOGENESIS AND MALE FERTILITY". Kent State University Honors College / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ksuhonors1376931171.
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Bulawa, Lillith. "The Effects of Total Body Proton Irradiation on Mouse Myometrium". Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/honors/548.
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The boundaries of human space exploration continue to expand with new technology and discoveries making it even more important to investigate the effects of space on biological systems. Although humans have explored space in small increments, reproductive studies must be conducted to determine if stable short- or long-term residences for humans can exist in space. This study explored the effects of whole-body proton radiation on uterine smooth muscle known as the myometrium. Two types of mice utilized in this study were C57BL/6 and B6.129S6Cybbtm1Din/J NOX2 knockout mice. C57BL/6 mice are standard laboratory mice that were used to represent the wildtype treatment group (N=18). The B6.129S6Cybbtm1Din/J NOX2 knockout mice have the NADPH Oxidase 2 gene shut off and represented the NOX2 Knockout treatment group (N=18). A third treatment group was made up of half of the C57BL/6 mice and were fed apocynin (N=18). Apocynin has been shown to inhibit NAPDH oxidase production in mice. NADPH Oxidase 2 is involved in the production of deleterious Reactive Oxygen Species (ROS); thus, apocynin should reduce the production of ROS in mice exposed to radiation. Different doses of radiation (0Gy, 0.5Gy, and 2.0Gy) were applied to the myometrium creating three different treatment subgroups within each mouse strain. The mice received 250 MeV protons at an approximate dose rate of 70cGy/ minute. Myometrium tissue was obtained one week following the radiation treatment. The uteri were removed, embedded, sectioned, and stained in hematoxylin and eosin solution. Thickness was determined by taking five measurements each of the outer longitudinal layer length, the inner circular layer length and the total length of both layers of the myometrium for three individual pieces of tissue for each animal. A one-way analysis of variance (ANOVA) was used to determine statistical differences between the groups and subgroups. Wildtype control mice exposed to 2.0Gy (N=5) of radiation had the thickest outer longitudinal layers compared to wildtype mice exposed to 0Gy (N=5) and 0.5Gy (N=6) (p=0.005, p=0). In the apocynin fed and Knockout treatment groups, the subgroups exposed to 0Gy had the thickest layers compared to their respective subgroups exposed to 0.5Gy and 2.0Gy. The apocynin fed mice exposed to 0Gy (N=6) outer longitudinal layer was statistically significantly thicker than the apocynin-fed mice exposed to 0.5Gy (p=0.004; N=6). The inner circular layer of the apocynin-fed mice exposed to 0.5Gy was statistically significantly thicker than the apocynin-fed mice exposed to 2.0Gy (p=0.001; N=6). Amongst the treatment groups, the wildtype control versus the apocynin fed mice exposed to 0Gy showed the apocynin-fed group to have the thicker outer longitudinal layer (p=0.003) and combined layers (p=0.001). Overall, the knockout group showed no statistical difference when compared to the wildtype control group. Further studies are necessary to reduce the possible confounding effect of the estrous cycle in the mice. The different phases of the mice estrus cycle may inadvertently affect the mouse uterine thickness due to the fluctuations in hormones. This study will add to the limited research regarding the female reproductive system in hopes of expanding the knowledge needed to actualize space colonization.
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Veras, Mariana Matera. "Efeitos da poluição do ar da cidade de São Paulo sobre o processo reprodutivo de camundongos com ênfase no desenvolvimento da placenta e cordão umbilical". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-31102008-125138/.
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A poluição do ar é um importante fator ambiental de risco para muitos desfechos gestacionais e reprodutivos negativos. Neste estudo nós investigamos os efeitos da poluição particulada em dois períodos de exposição (antes da concepção e durante a gestação) sobre alguns desfechos reprodutivos e gestacionais em camundongos. Utilizando câmaras de exposição, uma recebendo ar filtrado (F) e outra ar não-filtrado (nF), observamos que as fêmeas expostas ao ar não filtrado apresentaram alterações na duração do ciclo estral, estro persistente e o número de folículos antrais reduziu cerca de 36% (75±35,2, P=0,04) comparado às expostas ao ar filtrado (118,6 ±18,4). Nossos resultados mostram ainda um aumento significativo no tempo necessário para que o acasalamento ocorra, uma diminuição nos índices de fertilidade e gestação (P=0.003) nos casais expostos ao ar não filtrado (nF). A taxa média de perdas pós implantacionais (PPI) está aumentada em 70% (P0,005) no grupo de fêmeas expostas ao ar não filtrado antes e durante a gestação quando comparada ao grupo exposto antes de durante a gestação ao ar filtrado. O peso fetal (PF) é significativamente maior no grupo exposto nos dois períodos ao ar filtrado quando comparado aos demais grupos expostos antes e/ou durante a gestação ao ar não filtrado. O PF e a taxa média de PPI são influenciados tanto pela exposição durante a gestação quanto a exposição que ocorre antes da gestação. A exposição materna prévia a gestação e durante a primeira fase gestacional são críticas para o aumento no risco de baixo peso em camundongos. Nós também verificamos que a exposição ao ar não filtrado está associada a uma redução no volume, calibre e área de superfície dos espaços sanguíneos maternos, a um aumento na área de superfície dos capilares fetais, e na condutância de difusão da placenta. Alterações morfológicas no cordão umbilical também foram encontradas. Este estudo demonstra que a exposição aos níveis ambientais de poluição particulada de origem veicular afeta diferentes funções e estágios do processo reprodutivo. Nossos resultados também indicam que a exposição materna prévia está ligada a desfechos gestacionais negativos mesmo quando a exposição ocorre somente antes da concepçãoAir pollution is an important environmental health risk factor for many different gestational and reproductive negative outcomes. In this study we have investigated the effects of two different timing of exposure (before conception and during pregnancy) to urban ambient particulate matter on reproductive and pregnancy outcomes in mice. Using exposure chambers receiving filtered (F) and non-filtered (NF) we observed that exposed females presented changes in the length of estrus cycle, extended estrus and antral follicles number declined by 36% (P=0.04) in mice exposed to non filtered air (75±35.2) compared to mice exposed to filtered air(118.6 ±18.4). Our results further indicate a significant increase in time necessary to mating and decreased fertility and pregnancy indices (P=0.003) in NF couples. Mean postimplantation loss (PIL) rate was increased by 70% (P0.005) in the group exposed before and during pregnancy to non-filtered air when compared to the group exposed before and during pregnancy to filtered air. Fetal weight (FW) was significantly higher in group exposed during both periods to filtered air when compared to other groups exposed before and/or during pregnancy to non filtered air. FW and PIL mean rate were influenced by both pre-gestational (p<0.01) and gestational (p<0.01) period exposure. Maternal pre-gestational and the first stage of pregnancy exposure are critical to increased risk for low birth weight in mice. We also found that gestational exposure to non-filtered air was associated with reduced volumes, calibres and surface areas of maternal blood spaces and with greater fetal capillary surfaces and diffusive conductances of the placenta. Umbilical cord morphology was also altered. This study demonstrated that exposure to ambient levels of urban traffic generated particulate matter negatively affects different functions and stages of the reproductive process. Our results also indicate that maternal exposure to air pollution is linked to negative pregnancy outcomes even if maternal exposure occurs only before conception
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Santos, Paulo Henrique Rodrigues dos. "Benchmark: fertiliza??o de plantios de eucalipto em Minas Gerais". UFVJM, 2014. http://acervo.ufvjm.edu.br:8080/jspui/handle/1/337.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
O objetivo deste trabalho foi estudar os efeitos da fertiliza??o, do arranjo no espa?amento e da idade na produ??o de biomassa, na qualidade silvicultural e avalia??o econ?mica de um povoamento clonal de eucalipto. Foi instalado um experimento em ?reas do grupo Gerdau, no munic?pio de Tr?s Marias ? MG, utilizando o delineamento experimental em blocos ao acaso com esquema em faixas. Os tratamentos estudados, parcelas convencionais, consistiram de 15 fertiliza??es comerciais adotadas operacionalmente por empresas florestais, instaladas no estado de Minas Gerais. Nas subparcelas foram testados dois arranjos, 3,0 x 3,0 m e 6,0 x 1,5 m. As medi??es ocorreram aos 12, 24, 27, 36 e 48 meses. A partir das informa??es coletadas em campo, foram estimados para cada tratamento a biomassa por hectare, ?ndice de ?rea foliar, serrapilheira, al?m de outras vari?veis dendrom?tricas e de povoamento. Foi realizado o monitoramento da qualidade silvicultural na fase inicial de desenvolvimento da floresta por meio da vari?vel dendrom?trica de interesse das 50% menores ?rvores plantadas (Pvar50%). Realizou-se a avalia??o econ?mica com base na varia??o no custo da fertiliza??o de cada empresa e venda da madeira aos 48 meses. Verificou-se intera??o significativa nos valores de altura total e biomassa de tronco aos 12, 24, 36 e 48 meses, para di?metro m?dio e ?rea basal aos 12, 24 e 48 meses e biomassa de folha e galho aos 12 e 24 meses. Aos 27 meses apenas di?metro de copa e teor de clorofila obtiveram intera??o significativa e aos 36 meses altura total, altura de fuste, di?metro de copa e teor de clorofila foram significativos ? intera??o entre fertiliza??o e arranjo. ? medida que ocorre o desenvolvimento da floresta, o efeito da fertiliza??o vai se tornando menos pronunciado em rela??o ? produ??o de biomassa. Portanto, al?m da quantidade aplicada deve-se atentar para a propor??o entre os nutrientes aplicados. O crescimento em biomassa de tronco por hectare apresentou rela??o direta com os teores de clorofila e ?ndices de ?rea foliar. De forma geral, os tratamentos n?o influenciaram a uniformidade e o Pvar50 se mostrou adequado. O tratamento 1 (2000kg de agrosil?cio, 400kg de fosfato reativo, 130kg de 04:26:16+0,5%Cu+0,5%Zn e 150kg de KCl+1%B por hectare) no arranjo 3,0 x 3,0 m mostrou-se como a op??o mais atrativa segundo os crit?rios econ?micos avaliados, mesmo que ainda n?o esteja no ciclo final de corte da floresta.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014.
ABSTRACT The aim of this work was to study the fertilization effects, the arrangement on the spacing and the age on biomass production in silvicultural quality and economic evaluation of a clonal eucalyptus plantation. The experiment was conducted in Gerdau Group?s area, in Tr?s Marias - MG, using the experimental design randomised complete block with strip scheme. The treatments, which were studied, conventional commercial fertilization adopted operationally by 15 forestry companies, located in the Minas Gerais state. In the subplots two arrangements were tested, 3.0 x 3.0 m and 6.0 x 1.5 m. The measurements were performed at 12, 24 , 27 , 36 and 48 months. From the information collected in the field, were estimated for each treatment per hectare biomass, leaf area index, litterfall, and other variables dendrometric and stand. The monitoring of silvicultural quality was performed at the initial stage of forest development through dendrometric variable interest 50 % smallest trees planted (Pvar50 %). The economic evaluation was conducted based on the variation from fertilization cost of each company and the timber sale at 48 months. Was verified a significant interaction in the values of total height and truck biomass at 12, 24 , 36 and 48 months, average diameter and basal area at 12, 24 , and 48 months, leaf biomass and branches at 12 and 24 months. On the 27th months only canopy diameter and chlorophyll content had significant interaction and at 36 months total height, bole height, crown diameter and chlorophyll content had significant interaction between fertilization and arrangement. As forest development occurs, the fertilizing effect becomes less pronounced in relation to biomass production. So, besides the amount applied should pay attention to the proportion of the applied nutrients . The increase in truck biomass per hectare showed a direct relationship with the chlorophyll content and leaf area index . In general, the treatments did not affect the uniformity and Pvar50 was adequate. Treatment 1 (agrosil?cio of 2000kg , 400kg of reactive phosphate , 04:26:16 130kg of Cu +0.5 % +0.5 % Zn and 150 kg KCl +1 % B per hectare) 3.0 x 3.0 meters arrangement proved to be the most attractive option according to economic evaluation criteria , even if it is not already in the final cycle of forest cutting .
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Morgenthal, Theunis Louis. "The assessment of topsoil degradation on rehabilitated coal discard dumps / Theunis Louis Morgenthal". Thesis, North-West University, 2003. http://hdl.handle.net/10394/112.
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This study investigates coal discard cover soil fertility and its potential for
degradation, particularly in terms of its salinisation and acidification potential. Seven
rehabilitated coal discard dumps in the Witbank, Ermelo and Newcastle regions were
used as study areas. All areas were rehabilitated with a cover soil layer, revegetated
and annually fertilised with nitrate fertilisers, super phosphate, kraal manure and
lime. Performance guideline for pH of 5.5-(6.5 i0.5)-7.5 and electrical conductivity
guideline of preferably less than 200 mS.rn-' but not higher than 400 mS.m-' were set
based on literature information. Soil chemical data from a three-year fertilisation
programme were used to assess the fertility of the cover soil surface (0-150mm).
Data collected over a three year period as well as additional electrical conductivity
and pH measurements from the cover soil surface, subsoil, cover soil/coal contact
zone and underlying coal itself were used to assess the occurrence of salinisation
and acidification of the cover soil. The soil fertility varied significantly among dumps
as well as over the three years. Results indicated an increase in ammonium acetate
extractable macro elements (calcium, magnesium and potassium). With the
exception of manganese, no micro-element toxicities were recorded. Iron
concentrations were slightly elevated in some of the sandy cover soil layers. No
increase in soluble nitrogen (nitrate and ammonium) was found and most soluble
nitrogen was in the form of nitrates. In general the Bray extractable phosphate
increased during the study period. It can be predicted that with the following fertiliser
programme increases of exchangeable macro-elements as well as available
phosphorus can be expected. The study could not indicate an increase in adsorbed
or available nitrogen. Organic carbon was initially not analysed therefore no
comments can be made whether organic matter increased. Four of the seven dumps
surveyed had comparably similar organic carbon levels to the background samples.
Overall the fertiliser programme increased the electrical conductivity and decreased
the acidity of the cover soil surface. Acidity and salinity was in general not a problem
at the surface of the cover soil and pH was even slightly higher in cover soil samples.
The acidity and especially salinity increased at the subsoil and so did the sulphate
concentrations. Calcium and magnesium sulphate were predominantly responsible
for higher electrical conductivity measurements. The percentage exchangeable
sodium was also predominantly less than 2% indicating that sodicity is not currently a
problem in cover soil. Soil fertility was satisfactory for vegetation growth and macroelement
concentrations were in the correct ratio although calcium was slightly high.
An elevated sulphate concentration, in comparison to the natural grassland soils, as
well as a high salinity and high acidity in the subsoil layers indicate that salinisation
and acidification could deteriorate without proper management. A slightly acidic
cover soil can also be attributed partially to its natural acidic pH due to the wellweathered
and leach property of burrow pit. Higher than recommended salinity
levels were found in subsoil samples but the occurrence of acidification of the subsoil
was more dump specific. In relation to acidity and salinity guidelines only the cover
soil of one dump was concerning and the larger dumps subsoil acidity and salinity
were elevated.
The following management strategies are proposed:
a) The acidification potential, and therefore the pyrite content of the coal discard
must be considered during decisions making on the rehabilitation method
(clay barriers), topsoil depth, maintenance and mine closure potential.
b) The occasional monitoring of the subsoil's and coal contact acidity is
recommended, although not much can be done to stop acidification after
cover-soil placement.
c) To ensure a more sustained from of nitrogen supplementation over the long
term the use of selected legumes should be investigated. Research in
Europe and Australia suggested that nitrogen fixation could contribute
substantially to the nitrogen for plant uptake.
d) The physical properties of the topsoil (bulk density 8 soil compaction) are also
being neglected and needs to be assessed occasionally and interpreted
together with chemical analyses. Observations in other studies indicate that
this could be the most fundamental problem for vegetation growth and not
necessarily soil fertility, since soil physical properties could have a major
impact on root development.
Key words: Coal discard, mine rehabilitation, soil fertility, topsoil degradation,
salinisation, and acidificationThesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2004.
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Scohier, Alexandra. "Impact d'une mise en defens temporaire de prairies permanentes durant le pic de floraison : sélection alimentaire des brebis, diversité floristique et entomologique (Lepidoptera, Bombidae, Carabidae) des couverts". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00708561.
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L'érosion de la biodiversité prairiale est devenue une préoccupation majeure à l'échelle Européenne. Le pâturage ovin est supposé avoir un impact négatif sur la diversité prairiale, en raison de leur forte sélectivité pour les dicotylédones, indispensables aux insectes pollinisateurs. Comparés aux bovins, les ovins structurent peu les couverts et créent également moins de niches écologiques contrastées. L'objectif de cette thèse était de tester la faisabilité, et les bénéfices en pâturage ovin, d'une conduite en rotation dans laquelle une sous-parcelle est temporairement exclue du pâturage au moment du pic de floraison. Les effets de cette conduite ont été comparés à ceux d'un pâturage continu au même chargement. Au delà des indicateurs directs de performances zootechniques et de biodiversité (plantes, papillons, bourdons et carabes), nous avons analysé la sélection alimentaire des brebis dans les deux modes de conduite. Nous avons aussi cherché à appréhender comment la race et la fertilité du milieu pouvaient moduler la faisabilité d'un tel pâturage tournant et son intérêt vis-à-vis de la préservation de la biodiversité. Indépendamment de leur race, les brebis ont présenté une sélection alimentaire accrue vis-à-vis des dicotylédones dans les parcelles pâturées en rotation, qui a rapidement entraîné une diminution de leur richesse floristique en comparaison des parcelles pâturées en continu. L'augmentation de l'intensité de floraison des sous parcelles temporairement exclues de la rotation a favorisé les bourdons, probablement en raison de l'augmentation de la ressource en pollen et en nectar. En revanche, ce mode de gestion n'a pas permis d'augmenter la densité ni la richesse spécifique des papillons et des carabes. Le bénéfice d'une mise en défens temporaire d'une partie des parcelles semble donc moindre qu'en pâturage bovin. Définir les dates de mises en défens par rapport à la floraison d'espèces indicatrices, moduler la durée de la mise en défens en fonction de la pousse de printemps, et prolonger l'exclusion de certaines parcelles en automne et en hiver sont autant de pistes qu'il nous reste à explorer, afin de déterminer les conditions d'application optimale d'une telle conduite.
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Habarugira, Ildephonse. "Mise en place de référentiels morphologiques du développement de la fleur et de la graine chez la chicorée (Cichorium intybus L., Asteraceae)". Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10115/document.
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Dans le but de fournir une base de référence utile pour les études relatives au développement de la fleur et de la graine chez Cichorium intybus, le développement normal de la fleur, de l’akène et de la graine a été analysé histologiquement. A l’aide du référentiel établi pour le développement floral normal, nous avons pu montrer que la stérilité mâle nucléaire de type « Edith » observée chez la chicorée est associée à des perturbations dans les cellules du tapis et de la couche moyenne ainsi qu’à une dégénérescence des microspores qui a lieu après la formation des tétrades méiotiques. Les ressemblances histologiques entre le mâle stérile « Edith » avec certains mutants d’Arabidopsis thaliana et du riz ont servi dans le choix de gènes candidats lors de l’étude moléculaire de cette stérilité mâle. D’autre part, la stérilité mâle cytoplasmique nommée «524» créée par fusion de protoplastes de tournesol mâle stérile et de chicorée fertile, a aussi été analysée histologiquement. Lors du développement floral chez le mâle stérile « 524 », la dégénérescence des microspores commence avant la première mitose pollinique, si bien qu’à l’anthèse les grains de pollen sont vides; l’anthère reste indéhiscente et ratatinée et les parois des cellules de l’endothécium n’ont pas l’épaississement lignifié caractéristique de ce tissu. Par ailleurs, la caractérisation morphologique du développement floral chez les plantes portant le cytoplasme « 524 » nous a permis de mettre en évidence l’existence d’un mécanisme de restauration de la fertilité mais dont la nature génétique reste à déterminer. Pour le développement de l’akène et de la graine, la chronologie des événements ainsi que la caractérisation morphologique et physiologique des différents stades du développement de l’akène et de la graine ont révélé l’existence d’une variabilité génétique pour la durée du développement de l’akène et la graine chez la chicorée. Le référentiel du développement de l’akène et de l’embryon zygotique pourra servir notamment aux analyses d’expression des gènes candidats qui ont été identifiés pendant les études antérieures sur l’embryogenèse somatique chez la chicoréeIn order to provide a useful reference for morphological studies on flower and seed development in Cichorium intybus, the normal development for these two organs was histologically characterised. With reference to the morphological events during normal flower development, we have shown that nuclear male sterility type "Edith" is associated with disturbances in the tapetum and middle layer cells as well as degeneration of microspores after the formation of meiotic tetrads. Histological resemblance with some mutants in Arabidopsis thaliana and in rice helped for selection of candidate genes for molecular analysis of this male sterility. Moreover, the cytoplasmic male sterility named "524" which was created by fusion of protoplasts from sunflower male sterile and from fertile chicory was also histologically characterised. During flower development in the male sterile “524” degeneration of pollen grains occurs at the first pollen mitosis, so that at anthesis, the pollen grains are empty; the anther locules are unopened and shrivelled and no lignified secondary thickenings are observed in endothecium. Moreover, morphological characterisation of flower development in plants carrying the cytoplasm “524” led us to demonstrate the existence of a mechanism of fertility restoration for which heredity needs to be investigated. For the achene and seed development, the timing of events and morphological and physiological characterisation of developmental stages revealed genetic variability in the duration of achene and seed development in chicory. The reference established for achene and zygotic embryo development will help more particularly analysing expression of genes which have been previously shown to be involved in the somatic embryogenesis process in chicory
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Franco, Aline Aparecida. "Toxicidade de agroquímicos recomendados para a produção integrada de citros sobre o ácaro predador Euseius concordis (Chant) (Acari: Phytoseiidae)". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-26042017-104141/.
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As plantas cítricas brasileiras são acometidas por inúmeros artrópodes praga e agentes fitopatógenos causadores de doenças, que exigem pulverizações frequentes de agroquímicos para reduzir as perdas econômicas ocasionada por eles. No entando, esse intenso uso de compostos químicos podem ocasionar desiquilíbrios no agroecossistema, como a mortalidade de agentes de controle biológico. Neste sentido, objetivou-se com esse estudo avaliar os efeitos letal e subletais de inseticidas, acaricidas e fungicidas recomendados para a produção integrada de citros sobre o ácaro predador Euseius concordis (Chant) (Acari: Phytoseiidae) em condições de laboratório, além de estudar as interferências transgeracionais destes agroquímicos em aspectos de desenvolvimento e reprodução, estimando os parâmetros de tabela de vida da progênie das fêmeas de E. concordis que mantiveram contato residual, avaliando também a duração do efeito nocivo dos agroquímicos sobre adultos de E. concordis em condições de semi-campo, e para ter resultados mais completos, avaliou a capacidade de predação do E. concordis sobre formas jovens de Panonychus citri (McGregor) (Acari: Tetranychidae) em condições laboratoriais o que subsidiou os estudos de interferência de agroquímicos sobre a capacidade de predação de E. concordis. Os resultados demonstraram que ~ 73% dos inseticidas avaliados foram considerados moderadamente nocivos à nocivos à espécie em estudo, além disso, muitos dos inseticidas estudados tiveram interferência negativa nos parâmetros de tabela de vida da progênie (efeito transgeracional), e outros, como o imidacloprido, tiametoxam e lambda-cialotrina elevaram significativamente a taxa líquida de reprodução (Ro), taxa intrínseca de crescimento (rm) e razão finita de aumento (?), podendo indicar um possível efeito de hormese desses inseticidas à população de E. concordis. Já nos bioensaios com acaricidas, verificou que 50% dos avaliados foram considerados nocivos, causando altas mortalidades às fêmeas do ácaro estudado, destacando nesse grupo de agroquímicos o efeito trangeracional do acaricida etoxazol, que foi considerado inócuo a fêmeas adultas de E. concordis, no entanto, a progênie destas fêmeas teve mortalidade de 100% no estágio larval. Dos fungicidas avaliados, aproximadamente 70% foram considerados inócuos ou levemente nocivos às fêmeas de E. concordis (classe 1 e 2, segundo IOBC/ WPRS), sendo o grupo de agroquímicos menos nocivos ao ácaro em estudo. No presente trabalho, os resultados indicaram que, mesmo os agroquímicos considerados pouco nocivos ao ácaro predador E. concordis podem alterar o comportamento de busca e predação, como foi observado para as fêmeas que mantiveram contato residual com o fungicida tebuconazol e os inseticidas piriproxifem e tebufenozida, que reduziram significativamente a predação às ninfas de P. citri. Para tanto, esse estudo oferece informações que podem ser utilizadas em programas de manejo integrado de pragas, que preconize aliar controle químico com o biológico, com próposito de reduzir o uso de pesticida para controle de ácaros-praga, baseado na conservação do ácaro E. concordis nos pomares, além de fornecer informações pertinentes para estudos dessa natureza, direcionando para que os estudos de toxicidade sejam mais completos, baseando-se também nos efeitos transgeracionais e comportamentais que um pesticida pode causar a uma população de inimigos naturais.Brazilian citriculture are affected by numerous pest arthropods and phytopathogenic agents causing diseases that require frequent sprays of agrochemicals to reduce the economic losses caused by them. However, the intensive use of chemicals compounds can cause imbalances in the agroecosystem, like the mortality of biological control agents, for instance. In this sense, this study aimed to evaluate the lethal and sublethal effects of insecticides, acaricides and fungicides recommended for the integrated production of citrus on the predatory mite Euseius concordis (Chant) (Acari: Phytoseiidae) under laboratory conditions, in addition to studying the transgenerational interference of these agrochemicals in aspects of development and reproduction, estimating the life table parameters of the progeny of E. concordis females who kept contactwith the residues, also evaluating the duration of the harmful effects of agrochemicals on adult E. concordis in semi-field, and have more complete results, evaluated the capacity predation of E. concordis on young stages of Panonychus citri (McGregor) (Acari: Tetranychidae) in laboratory conditions, that supported pesticide interference studies on the predation of E. concordis. The results showed that ~ 73% of the insecticides were moderately harmful to harmful, concerning the studied species, and that many of the agrochemicals studied have negative interference in the life table parameters of progeny (transgenerational effect). Others, such as imidacloprid, thiamethoxam and lambda-cyhalothrin significantly increased the net reproductive rate (Ro), intrinsic rate of increase (rm) and finite rate of increase (λ), which may indicate a possible hormesis effect of these insecticides to the population of E. concordis. But, in cases of the bioassays with acaricides, it was found that 50% of the evaluated ones were considered harmful, causing high mortality to the female of this mite, highlighting in this group of agrochemicals the trangeracional effect of etoxazole, which was considered harmless to adult females of E. concordis, however, the offspring of these females had 100% of mortality in the larval stage. From the fungicides evaluated, approximately 70% were considered harmless or slightly harmful to E. concordis females (class 1 and 2, according IOBC / WPRS), being, these ones, the less harmful agrochemicals group to mite study. This study also assessed that even agrochemicals considered less harmful to predatory mite E. concordis can change the search and predation behavior, as observed for females who have maintained residual contact with fungicides tebuconazole and insecticides pyriproxyfen and tebufenozide, which significantly reduced predation of P. citri nymphs. Therefore, this study provides information that can be used in integrated pest management programs, which would include combining chemical with biological control, with the porpose of reducing the use of pesticide to control pest mites, based on the conservation of E. concordis in the groves, as well as providing relevant information for such studies, directing that the toxicity studies are more complete, also based on transgenerational and behavioral effects that a pesticide can cause in a population of natural enemies.
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Monteiro, Alexandre Richardson Oliveira. "An?lise do grau de prote??o do Aqu?fero Barreiras em per?metros sob fertiliza??o qu?mica a partir de dados hidrogeof?sicos - ?rea da bacia do Rio Catu-RN". Universidade Federal do Rio Grande do Norte, 2015. http://repositorio.ufrn.br/handle/123456789/21184.
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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
A utiliza??o de fertiliza??o qu?mica em per?metros agricult?veis proporciona um incremento da produtividade, embora eventualmente possa ocasionar uma deprecia??o qualitativa do manancial h?drico subterr?neo, sobretudo se este for de natureza n?o confinada. Nesse contexto, o presente trabalho apresenta resultados referentes a uma an?lise do grau de prote??o natural do Aqu?fero Barreiras em uma ?rea situada no litoral leste do Estado do Rio Grande do Norte-Brasil. O referido aqu?fero ? de natureza cl?stica e possui car?ter hidr?ulico n?o confinado, fato este que naturalmente lhe confere uma susceptibilidade ? contamina??o, proveniente de eventuais cargas contaminantes impostas na superf?cie do terreno. Estes contaminantes estariam associados com a lixivia??o de excedentes da fertiliza??o n?o assimilados pela vegeta??o. A metodologia utilizada foi fundamentada na utiliza??o conjunta de dados hidrogeof?sicos, particularmente de modelos inversos de sondagens el?tricas verticais-SEVs e informa??es de perfis de po?os, possibilitando a obten??o de cartografias de condut?ncia longitudinal (S), dada em mili-Siemens (mS), e vulnerabilidade do aqu?fero. Essas cartografias foram elaboradas com ?nfase para a zona n?o saturada sobrejacente, ressaltando sobretudo sua espessura e ocorr?ncia de litologias argilosas. Dessa forma, o mapa de condut?ncia longitudinal e vulnerabilidade revelaram ?reas mais suscept?veis ? contamina??o nos setores nordeste e centro-leste da ?rea de estudo, com valores iguais ou inferiores a 10mS e maiores ou iguais a 0.50, respectivamente. Por outro lado, o setor sudoeste mostrou-se menos suscept?vel ? contamina??es, com valores de condut?ncia longitudinal e ?ndices de vulnerabilidade maiores ou iguais a 35mS e menores ou iguais a 0.40, respectivamente.
The use of chemical fertilization in arable perimeters provides increased productivity, though it can eventually lead to a qualitative depreciation of groundwater sources, especially if such sources are unconfined in nature. In this context, this thesis presents results from an analysis of the level of natural protection of the Barreiras Aquifer in an area located on the eastern coast of the Rio Grande do Norte State - Brazil. Such an aquifer is clastic in nature and has an unconfined hydraulic character, which clearly makes it susceptible to contamination from surface ground loads with contaminants associated with the leaching of excess fertilizers not absorbed by ground vegetation. The methodology used was based on the use of hydro-geophysical data, particularly inverse models of vertical electrical soundings (VES) and information from well profiles, allowing the acquisition of longitudinal conductance cartographies (S), data in mili-Siemens (mS), and the vulnerability of the aquifer. Such maps were prepared with emphasis to the unsaturated overlying zone, highlighting in particular its thickness and occurrence of clay lithologies. Thus, the longitudinal conductance and aquifer vulnerability reveal areas more susceptible to contamination in the northeast and east-central sections of the study area, with values equal to or less than 10mS and greater than or equal to 0,50, respectively. On the other hand, the southwestern section proved to be less susceptible to contamination, whose longitudinal conductance and vulnerability indices are greater than or equal to 30mS and less than or equal to 0,40, respectively.
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Ponsard, Claire. "Effets d'une restriction alimentaire après vêlage chez la vache allaitante sur la fertilité à l'œstrus induit, la sécrétion de LH et l'activité ovarienne : liens avec le métabolisme énergétique et intérêt d'une supplémentation énergétique avant la mise à la reproduction". Nancy 1, 2000. http://www.theses.fr/2000NAN11303.
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Boden, Michael James. "The role of circadian rhythms in reproduction development and fertility in the bmal1 null mouse /". 2008. http://hdl.handle.net/2440/48491.
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Circadian rhythms are the endogenous cycling of hormones, activity patterns and gene expression that occur across 24 hours. Disruption of circadian rhythms has been associated with multiple health complications, including reduction of fertility. The bmal1 mouse provides an animal model for central and peripheral loss of rhythmicity. Herein the reproductive function and postnatal development in the bmal1 knockout mouse has been evaluated. The reproductive capability of the heterozygous breeding colony was investigated, with around 50% of the female breeder mice becoming pregnant within one estrus cycle. The offspring of the colony had a higher than expected level of perinatal mortality while the knockout and heterozygous genotype was under represented among the offspring surviving to weaning, suggesting high knockout embryo or perinatal losses. The circadian phenotype of this mouse model was confirmed, identifying the severe disruption of circadian behavioural rhythms. Further, the growth of the bmal1 knockout mice was retarded compared with their heterozygous and wild type littermates from weaning to 9 months of age. The reproductive function of the homozygous male bmal1 knockout mouse was evaluated. They showed poor fertility, poorly developed secondary sexual organs, reduced sperm count and reduced sperm motility. Female bmal1 knockout mice had delayed vaginal opening, delayed onset of first estrus, disrupted estrus cyclicity as well as impaired reproductive and mammary tissue development. Steroid hormone synthesis was compromised in both males (testosterone) and females (progesterone) and ovarian morphology revealed reduced corpora lutea formation and structural abnormalities. Female bmal1 knockout mice also evidenced profound infertility, which was caused by a continuum of reproductive insufficiencies including reduced ovulation of oocytes, poorer progression of the preimplantation embryo and failure to successfully implant in the uterus. While the ovaries of bmal1 knockout females were able to respond to exogenous stimulation, the number of ovulated oocytes was reduced, the fertilised oocytes were of reduced quality, progressed poorly to mature blastocyst and once again failed to implant. A bioinformatical evaluation of a panel of genes closely involved in reproduction and ovarian function was analysed for the presence of circadian enhancer regions (E-box sequences) or RORA response elements (RRE) in their promoter regions. It was revealed that many of the genes investigated contained one or more circadian E-box and RRE sequence, providing a mechanism for the disruption of circadian gene expression within the ovary to cause detrimental changes in gene expression. Further to this, the gene expression profile of these functional genes and clock genes were evaluated in ovarian tissues from wild type and knockout mice across the estrus cycles and across 24 hours. It was shown that the murine ovary rhythmically expressed the genes involved with the molecular clock across 24 hours, as well as several other genes previously associated with rhythmicity in peripheral tissues. Further, the loss of functional bmal1 gene expression resulted in up or down regulation of over 75% of the functional genes investigated, including steroidogenic acute regulatory protein (the rate limiting enzyme for progesterone synthesis). In conclusion, the bmal1 knockout mouse shows a significant multi-factorial loss in fertility in both males and females. This loss occurs across a range of tissues and results in heavily reduced fertility in the male and complete infertility in the female. Further research could identify in greater detail the precise molecular mechanisms underpinning of this disruption.Thesis (Ph.D.) -- University of Adelaide, School of Paediatrics and Reproductive Health, 2008
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Boden, Michael James. "The role of circadian rhythms in reproduction: development and fertility in the bmal1 null mouse". Thesis, 2008. http://hdl.handle.net/2440/48491.
Texto completo da fonteResumo:
Circadian rhythms are the endogenous cycling of hormones, activity patterns and gene expression that occur across 24 hours. Disruption of circadian rhythms has been associated with multiple health complications, including reduction of fertility. The bmal1 mouse provides an animal model for central and peripheral loss of rhythmicity. Herein the reproductive function and postnatal development in the bmal1 knockout mouse has been evaluated.
The reproductive capability of the heterozygous breeding colony was investigated, with around 50% of the female breeder mice becoming pregnant within one estrus cycle. The offspring of the colony had a higher than expected level of perinatal mortality while the knockout and heterozygous genotype was under represented among the offspring surviving to weaning, suggesting high knockout embryo or perinatal losses. The circadian phenotype of this mouse model was confirmed, identifying the severe disruption of circadian behavioural rhythms. Further, the growth of the bmal1 knockout mice was retarded compared with their heterozygous and wild type littermates from weaning to 9 months of age.
The reproductive function of the homozygous male bmal1 knockout mouse was evaluated. They showed poor fertility, poorly developed secondary sexual organs, reduced sperm count and reduced sperm motility. Female bmal1 knockout mice had delayed vaginal opening, delayed onset of first estrus, disrupted estrus cyclicity as well as impaired reproductive and mammary tissue development. Steroid hormone synthesis was compromised in both males (testosterone) and females (progesterone) and ovarian morphology revealed reduced corpora lutea formation and structural abnormalities. Female bmal1 knockout mice also evidenced profound infertility, which was caused by a continuum of reproductive insufficiencies including reduced ovulation of oocytes, poorer progression of the preimplantation embryo and failure to successfully implant in the uterus. While the ovaries of bmal1 knockout females were able to respond to exogenous stimulation, the number of ovulated oocytes was reduced, the fertilised oocytes were of reduced quality, progressed poorly to mature blastocyst and once again failed to implant.
A bioinformatical evaluation of a panel of genes closely involved in reproduction and ovarian function was analysed for the presence of circadian enhancer regions (E-box sequences) or RORA response elements (RRE) in their promoter regions. It was revealed that many of the genes investigated contained one or more circadian E-box and RRE sequence, providing a mechanism for the disruption of circadian gene expression within the ovary to cause detrimental changes in gene expression. Further to this, the gene expression profile of these functional genes and clock genes were evaluated in ovarian tissues from wild type and knockout mice across the estrus cycles and across 24 hours. It was shown that the murine ovary rhythmically expressed the genes involved with the molecular clock across 24 hours, as well as several other genes previously associated with rhythmicity in peripheral tissues. Further, the loss of functional bmal1 gene expression resulted in up or down regulation of over 75% of the functional genes investigated, including steroidogenic acute regulatory protein (the rate limiting enzyme for progesterone synthesis).
In conclusion, the bmal1 knockout mouse shows a significant multi-factorial loss in fertility in both males and females. This loss occurs across a range of tissues and results in heavily reduced fertility in the male and complete infertility in the female. Further research could identify in greater detail the precise molecular mechanisms underpinning of this disruption.Thesis (Ph.D.) -- University of Adelaide, School of Paediatrics and Reproductive Health, 2008
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Gratao, Ana Angélica [Verfasser]. "Impaired fertility in transgenic mice overexpressing betacellulin / by Ana Angélica Gratao". 2007. http://d-nb.info/98368698X/34.
Texto completo da fonte
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Johnson, Sarah A. "Behavioral, physiological, and molecular mechanisms underlying reduced fertility in Nhlh2 knockout mice". 2005. https://scholarworks.umass.edu/dissertations/AAI3163678.
Texto completo da fonteResumo:
Successful reproduction in mammals requires the interaction of the reproductive and neuroendocrine systems. Nhlh2 is a basic helix-loop-helix transcription factor that is expressed in both the developing and adult neuroendocrine hypothalamus. Targeted deletion (N2KO) of Nhlh2 results in hypogonadism and obesity. In addition, male N2KO mice exhibit micropenis and reduction of male accessory sex organs and half of the female N2KO mice have thread-like uteri and small pale ovaries. Male N2KO mice have reduced levels of testosterone and FSH, and are infertile, while female N2KO are not completely infertile, but show a decline in reproductive potential as they age. In order to determine if the mechanisms underlying reduced fertility in N2KO male and female mice, we examined gamete number and competence, hormone concentrations and sexual behavior. We found that although sperm from KO mice is as functional as sperm from normal mice in IVF assays, N2KO mice have a 50% reduction in the number of mature sperm isolated from the caudal epididymis. Oocyte numbers in N2KO female is decreased with aging, but were competent for fertilization and development. Like N2KO males who are unresponsive to sexually receptive female mice, N2KO females show reduced lordosis when placed with an experienced male. Based on these findings we examined mRNA levels of estrogen receptor alpha (ERα) and progesterone receptor (PR), as they are important in the regulation of female and male sexual behavior. In wildtype (WT) female mice, a decline in ERα production is seen in response to the addition of estrogen. In N2KO females this decline is not observed; ERα levels are increased compared to WT females during proestrus. In male N2KO there is an increase in progesterone receptor mRNA levels. These data suggest that Nhlh2 may play a role in sexual behavior possibly via the regulation of ERα and progesterone receptor.
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Yaeram, Jakrit. "The effect of whole body heating on testis morphology and fertility of male mice / by Jakrit Yaeram". Thesis, 2002. http://hdl.handle.net/2440/21887.
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杉山, 知里, e Chisato Sugiyama. "Fertility and Pregnancy-Associated ß-Cell Proliferation in Mice Deficient in Proglucagon-Derived Peptides". Thesis, 2013. http://hdl.handle.net/2237/18601.
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Xiao, Guan-Yu, e 蕭冠宇. "The Potential of Mouse Amniotic Fluid Stem Cells to Rescue Fertility of Ovarian Failure Mice". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/55079234525709352337.
Texto completo da fonteResumo:
碩士國立臺灣大學
動物科學技術學研究所
100
The dogma of reproductive biology field is that female mammalian loss of germ cell renewal ability before birth, then the reserve of germ cells decreased during postnatal life until exhaustion, resulting in menopause and irreversible ovarian failure. Previous studies demonstrated that bone marrow-derived cells can rescue the fertility of mouse treated with drugs, busulfan and cyclophosphamide, which damage the germ cells in cancer patients. However, there was no evidence shown the restoring pathway of bone marrow-derived cells whether via germ cell differentiation, ovarian cell differentiation or paracrine factors secretion. Recently, it was reported that amniotic fluid stem cells (AFSCs) have low immunogenicity to avoid immunorejection and may have better differentiation ability than mesenchymal stem cells (MSCs). Therefore, we intend to investigate if AFSCs can recover female fertility via germline differentiation. In this study, we established mouse AFSCs (mAFSCs) which expressing foreign enhanced green fluorescence protein (EGFP) that derived from EGFP bearing mouse conceptus (11.5 days). These mAFSCs exhibited the characteristics similar to bone marrow MSCs, and have the higher proliferation ability. In addition, mAFSCs express the pluripotent specific marker-Oct 4, and could differentiate into adipocyte, osteocyte and chondrocyte under appropriate condition. When mAFSCs were induced to differentiate into female germ cell, a subpopulation of these cells detached to each other gradually and formed aggregates resembling female germ cell formation. These cells subsequently expressed the germ cell marker-DAZL under induction condition. On further differentiation, these cells which formed the follicle-like structure that secreted estradiol under gonadotropin stimulation. Twenty-five days after differentiation induction, a few cells showed oocyte-like morphology and expressed the germ cell specific marker-VASA as well. To evaluate whether mAFSCs can recover female fertility, we use the ovarian failure model mice as recipients, and then transplanted EGFP bearing mAFSCs (EGFP-mAFSCs) into ovary of recipient mice. Four weeks after cell transplantation, numbers of developing follicle within host ovaries were significant higher than ovarian failure model mice, and numbers of atretic follicle were significant decreased. In addition, the fertility of all recipients was restored, but there was no fetus derived from EGFP-mAFSCs. Although EGFP-mAFSCs was observed within ovary after one month of transplantation, there was no evidence shown that mAFSCs differentiated into germ cell. Collectively, this study demonstrated that mAFSCs have the potential to differentiate into germline in vitro. In addition, in vivo trial verified that mAFSCs can rescue the fertility in ovarian failure mice may via paracrine factors secretion. These findings implicated that the potentiality of clinical cell-transplantation therapy for the treatment of infertility.
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Young, Samantha Allison Mary. "Generation of gene disrupted mice to further elucidate the reproductive mechanisms of male factor fertility". Thesis, 2016. http://hdl.handle.net/1959.13/1325823.
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Research Doctorate - Doctor of Philosophy (PhD)The issue of fertility is one of increasing importance in a global context, with infertility on the rise, along with increased use of assisted reproductive technologies. Yet our understanding of these often incredibly complex processes is still low, due in part to the difficulty in replicating the in vivo environment of fertilization in an in vitro setting, for any length of time. To counter this, we turn to genetically modified organisms, however, in the past the generation of animal models has been expensive, difficult and time consuming. The adaptation of the CRISPR/Cas9 system of genetic engineering to work in mammalian cells has allowed us to explore more than ever the role of certain genes in reproduction. One such animal model that is of particular use is the mouse. They are genetically similar to humans, allowing us to investigate conserved genes with potentially similar functions. They also have a relatively short reproductive cycle, making them effective for genetic modification, as several generations can be analysed within a short span of time. Herein, we examine the various uses of the CRISPR/Cas9 system in the mouse to target the specific area of male factor fertility. This system has developed dramatically in the few years that it has been available, from being able to generate a total gene knockout to subtler genetic modifications. We begin by utilizing the most basic function of the CRISPR/Cas9 system, generating a total gene knockout. Here, we describe for the first time the in vivo role of a gene previously thought to be linked to capacitation. The calcium-binding tyrosine phosphorylation-regulated protein (CABYR) is known in the literature to bind to the fibrous sheath of sperm flagella, however, by removing Cabyr by CRISPR/Cas9 gene knockout we observed that the role of CABYR is in fact in the correct formation of the fibrous sheath. This discovery adds much to the knowledge of the formation and function of the sperm flagella, perhaps even providing a diagnosis for male factor infertility due to poor sperm motility, which has previously been labelled as unexplained male factor infertility. This thesis also explores the use of CRISPR/Cas9 to delete regions of the genome, as well as performing amino acid substitutions. Whilst the genes chosen for these experiments led to no change in the fertility phenotype, it is the ability of the CRISPR/Cas9 system to perform these genetic modifications that is of great interest. The genes selected for this study were all involved in the formation or function of the dynein complex, the motor system that provides the flagella with the ability to move. The selection of these genes came from proteomic work that indicated phosphorylation changes, indicating a control mechanism for sperm motility. The fact that CRISPR/Cas9 could be used to substitute to potential phosphorylation sites demonstrates how much further we can take the investigation of fertility with the use of this system. Finally, we explored the use of the CRISPR/Cas9 system to insert a single nucleotide, creating a premature stop codon and truncation of the protein. The gene targeted was Izumo1. This gene is already known to be essential for fertilisation, yet with CRISPR/Cas9 we can study the individual domains of this, or other proteins in vivo. Taken together, the findings in this thesis demonstrate the many uses of the CRISPR/Cas9 system to investigate male factor fertility. This collection of studies explores its use from the basic, creating total gene knockouts, to the refined and subtle, amino acid substitution and insertion of a single nucleotide. The demonstration herein is of the potential of this system to address the specific needs of fertility research. Genes involved in fertility are often complex and backed up by several others to create significant redundancy. As shown with the CABYR knockout, in vitro investigation is not enough to give an accurate understanding of the role of any given gene. The advent of the CRISPR/Cas9 system with its simplicity, ease of use and speed renders it suitable as a tool for investigating the complex processes of male factor fertility.
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Xiao, Guan-Yu, e 蕭冠宇. "The Therapeutic Potential and Mechanism of Amniotic Fluid StemCells in Rescuing Fertility in Mice with Chemotherapy-InducedPremature Ovarian Failure". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/13283735197195600472.
Texto completo da fonteResumo:
博士國立臺灣大學
生物科技研究所
104
Chemotherapy (CTx) is commonly used for treating various malignant tumors and for improving the survival rate of cancer patients. However, CTx causes damage to ovarian granulosa cells (GCs), which are required for oocyte survival and follicle development, and results in irreversible premature ovarian failure (POF) in female patients. Recently, amniotic fluid stem cells (AFSCs) emerge as a novel source for regenerative medicine due to their easy accessibility, primitive stage and low immunogenicity. These findings suggest the potential of AFSCs for treating ovarian failure in clinic, but its restorative efficacy and mechanisms are still unclear. In this study, AFSCs were isolated from transgenic mice that ubiquitously express enhanced green fluorescence protein (EGFP), which enables us to trace the fate of AFSCs after transplantation. These AFSCs exhibit morphologies, immunophenotypes, and mesoderm trilineage differentiation potentials similar to mesenchymal stem cells (MSCs). Further, AFSCs proliferate faster than MSCs and express OCT4, a marker for pluripotency. After transplanting into the ovaries of CTx-mice, AFSCs could rescue the reproductive ability of CTx-mice by preventing follicle atresia and sustaining the healthy follicles. Notably, the transplanted AFSCs did not differentiate into GCs and germline cells in vivo. Next, I demonstrate that the therapeutic effects of AFSCs mainly derived from their secretory factors in which AFSC-derived exosomes reproduce the anti-apoptotic effect on CTx-damaged GCs. AFSC-derived exosomes prevent ovarian follicular atresia in CTx-mice via the delivery of microRNAs (miRNAs) in which both miR-146a and miR-10a are highly enriched and their potential target genes are critical to apoptosis. Down-regulation of these two miRNAs in AFSC-derived exosomes attenuates the anti-apoptotic effect on CTx-damaged GCs in vitro whereas administration of these miRNAs recapitulates the effects both in vitro and in vivo in which miR-10a contributes a dominant influence. These findings suggest a potential mechanism for the effects of AFSCs on CTx-damaged ovaries and the dominant role of miR-10a in the regenerative process that implies the promise of a new cell-free therapeutics for treating POF.
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Mehregan, Aujan. "Characterization of Calcium Homeostasis Parameters in TRPV3 and CaV3.2 Double Null Mice". 2017. https://scholarworks.umass.edu/masters_theses_2/596.
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In mammals, calcium influx is required for oocyte maturation and egg activation, as it supports the persistent calcium oscillations induced by fertilization. These oscillations are required for the initiation of embryo development. The molecular identities of the plasma membrane calcium-permeant channels that underlie calcium influx are not established. Among these channels, Transient Receptor Potential Vanilloid, member 3 (TRPV3) allows divalent cations, namely strontium (Sr2+) and calcium (Ca2+) with high permeability, into cells, and its expression pattern seems to predict an essential role in the initiation of development. Another channel that was identified to be expressed in oocytes/eggs is the low-voltage-activated T-type channel, CaV3.2. However, the ability to accurately probe the expression and function of these channels on Ca2+ homeostasis in mouse eggs is hindered by the lack of specific and known pharmacological agents and antibodies for these channels.
Here, we simultaneously knockout out these two Ca2+ influx channels in the mouse to explore the effects on Ca2+ homeostasis. We examined fertility rates, development, and morphological defects that arose from the double null pups. Next, we investigated the consequences on Ca2+ store content in immature and mature oocytes and eggs. We also examined the effects on fertilization-induced Ca2+ oscillations in response to in vitro fertilization and PLCz cRNA microinjection. We found that female mice null for these channels display drastic subfertility compared to the single knockout mice for these channels. Additionally, the Ca2+ store content is significantly diminished in double knockout eggs versus controls, as was the frequency of the fertilization-induced Ca2+ oscillations. These results suggest that these channels play a crucial role in Ca2+ influx during maturation and contribute to maintain Ca2+ oscillations post-fertilization. These null oocytes and eggs will be an important tool to perform electrophysiological studies to accurately measure the native current(s) of a specific channel(s) in eggs, and to identify the channel(s) that mediate Ca2+ during fertilization.
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Eskandari, Shahraki Marzieh. "Knockout mouse model generated by CRISPR technology to study the function of BSP proteins on male fertility in vivo". Thèse, 2019. http://hdl.handle.net/1866/22595.
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McGrath, Leanne Jane. "The impact of exogenous TGFβ1 on male reproductive function". 2008. http://hdl.handle.net/2440/50730.
Texto completo da fonteResumo:
The TGFβ family of cytokines are potent signalling molecules that regulate tissue development, inflammation and immunity. Previous studies in mice with a null mutation in the Tgfb1 gene (TGFβ1-/- mice) implicate a key role for TGFβ1 in male reproductive function. These mice show profound infertility due to an inability to copulate successfully, associated with reduced testosterone and sperm production. The focus of this project was to 1) further characterize mechanisms underpinning reproductive deficiency in male TGFβ1-/- mice, 2) identify a reliable physiological marker of TGFβ1 availability in vivo, and 3) to determine whether exogenous TGFβ1 administration influences TGFβ1 availability and restores fertility. To investigate the causes of unsuccessful copulation by TGFβ1-/- mice, penis morphometry was examined. Penile organ structure, as assessed by scanning electron microscopy, was comparable between genotypes however a superfluous epidermal covering that impeded penile spine protrusion was evident in TGFβ1-/- mice. The epidermal covering was not due to increased epithelial cell proliferation, as measured by Brdu labelling and immunohistology. Behavioural observations of erectile activity showed that TGFβ1-/- mice achieved spontaneous erections albeit at reduced frequency compared to TGFβ1+/+ mice. The efficacy of exogenous TGFβ1 replacement was evaluated by first identifying measures of in vivo TGFβ1 availability and/or function and selecting an effective route of administration. Serum TGFβ1 and testosterone levels were reliable discriminators of TGFβ1 genotype. Gene expression and phagocytic function of peritoneal macrophages revealed no differences between genotypes. Exogenous sources of TGFβ1 for replacement studies included colostrum, naturally occurring in breast milk and recombinant human latent TGFβ1 (rhLTGFβ1). Colostrum did not increase circulating levels and rhTGFβ1 injection caused only transient elevation of serum levels. Thus mini-osmotic pumps were used to deliver a constant supply of cytokine to TGFβ1-/- mice. The fertility status of TGFβ1-/- mice receiving exogenous TGFβ1 was investigated. Reproductive behaviour in response to normal receptive female mice was assessed twice during treatment, on day 7 and day 14. Blood, liver and reproductive tissues were collected at sacrifice. Circulating TGFβ1 was increased in TGFβ1 treated TGFβ1-/- mice above TGFβ1-/- control levels, although this did not affect circulating testosterone. Erectile activity and sperm production were unchanged. Videotaping behaviour with estrous females revealed that the TGFβ1+/+ mice successfully mounted and intromitted, unlike the TGFβ1-/- controls. The TGFβ1-/- mice receiving exogenous TGFβ1 displayed moderately enhanced mounting and intromission behaviour although this remained less frequent than in the TGFβ1+/+ controls. Ejaculation behaviour was not observed in any TGFβ1-/- mice regardless of TGFβ1 replacement, compared to TGFβ1+/+ controls where >90% mice displayed ejaculated. Modest improvement in the copulation activity of the TGFβ1-/- mice receiving exogenous TGFβ1 suggests that systemic TGFβ1 availability can influence reproductive performance in male TGFβ1-/- mice. However since fertility was not restored, locally produced TGFβ1 in the reproductive tract and/or hypothalamic pituitary axis are also implicated in regulating fertility. These findings advance our knowledge of the role of the TGFβ1 cytokine in male reproductive physiology and may have relevance for devising new treatments for infertility and erectile dysfunction in men.Thesis (Ph.D.) - University of Adelaide, School of Paediatrics and Reproductive Health, 2008
44
McGrath, Leanne Jane. "The impact of exogenous TGFβ1 on male reproductive function". Thesis, 2008. http://hdl.handle.net/2440/50730.
Texto completo da fonteResumo:
The TGFβ family of cytokines are potent signalling molecules that regulate tissue development, inflammation and immunity. Previous studies in mice with a null mutation in the Tgfb1 gene (TGFβ1-/- mice) implicate a key role for TGFβ1 in male reproductive function. These mice show profound infertility due to an inability to copulate successfully, associated with reduced testosterone and sperm production. The focus of this project was to 1) further characterize mechanisms underpinning reproductive deficiency in male TGFβ1-/- mice, 2) identify a reliable physiological marker of TGFβ1 availability in vivo, and 3) to determine whether exogenous TGFβ1 administration influences TGFβ1 availability and restores fertility.
To investigate the causes of unsuccessful copulation by TGFβ1-/- mice, penis morphometry was examined. Penile organ structure, as assessed by scanning electron microscopy, was comparable between genotypes however a superfluous epidermal covering that impeded penile spine protrusion was evident in TGFβ1-/- mice. The epidermal covering was not due to increased epithelial cell proliferation, as measured by Brdu labelling and immunohistology. Behavioural observations of erectile activity showed that TGFβ1-/- mice achieved spontaneous erections albeit at reduced frequency compared to TGFβ1+/+ mice.
The efficacy of exogenous TGFβ1 replacement was evaluated by first identifying measures of in vivo TGFβ1 availability and/or function and selecting an effective route of administration. Serum TGFβ1 and testosterone levels were reliable discriminators of TGFβ1 genotype. Gene expression and phagocytic function of peritoneal macrophages revealed no differences between genotypes. Exogenous sources of TGFβ1 for replacement studies included colostrum, naturally occurring in breast milk and recombinant human latent TGFβ1 (rhLTGFβ1). Colostrum did not increase circulating levels and rhTGFβ1 injection caused only transient elevation of serum levels. Thus mini-osmotic pumps were used to deliver a constant supply of cytokine to TGFβ1-/- mice.
The fertility status of TGFβ1-/- mice receiving exogenous TGFβ1 was investigated. Reproductive behaviour in response to normal receptive female mice was assessed twice during treatment, on day 7 and day 14. Blood, liver and reproductive tissues were collected at sacrifice. Circulating TGFβ1 was increased in TGFβ1 treated TGFβ1-/- mice above TGFβ1-/- control levels, although this did not affect circulating testosterone. Erectile activity and sperm production were unchanged. Videotaping behaviour with estrous females revealed that the TGFβ1+/+ mice successfully mounted and intromitted, unlike the TGFβ1-/- controls. The TGFβ1-/- mice receiving exogenous TGFβ1 displayed moderately enhanced mounting and intromission behaviour although this remained less frequent than in the TGFβ1+/+ controls. Ejaculation behaviour was not observed in any TGFβ1-/- mice regardless of TGFβ1 replacement, compared to TGFβ1+/+ controls where >90% mice displayed ejaculated.
Modest improvement in the copulation activity of the TGFβ1-/- mice receiving exogenous TGFβ1 suggests that systemic TGFβ1 availability can influence reproductive performance in male TGFβ1-/- mice. However since fertility was not restored, locally produced TGFβ1 in the reproductive tract and/or hypothalamic pituitary axis are also implicated in regulating fertility. These findings advance our knowledge of the role of the TGFβ1 cytokine in male reproductive physiology and may have relevance for devising new treatments for infertility and erectile dysfunction in men.Thesis (Ph.D.) - University of Adelaide, School of Paediatrics and Reproductive Health, 2008
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LIU, YUNG-LIANG, e 劉勇良. "Fertility study1.OSR1 and SPAK collaboratively regulate Sertoli cell support of spermatogenesis in mice through modulation of NKCC12.Investigation of the therapeutic potentials of decoy receptor 3 in the abortion-prone mouse model and analysis of its mechanism". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/2cd545.
Texto completo da fonteResumo:
博士國防醫學院
醫學科學研究所
105
ABSTRACT (OSR1/SPAK) Somatic Sertoli cells (SCs) play a key role in orchestrating the development of sperm cells through the stages of spermatogenesis and their function is important for male fertility. Sertoli-cell-only syndrome (SCOS), is not an uncommon disorder in male infertility, characterized with a condition of the testes in which only Sertoli cells line the seminiferous tubules. The etiology and mechanism of this syndrome are currently unknown. Oxidative stress-responsive kinase-1 (OSR1) and STE20 (sterile 20) and SPS1-related proline/alanine-rich kinase (SPAK), belong to STE20 superfamily of MAPK-like protein kinases, and express in testis tissues. We investigated the roles of OSR1 and SPAK in mouse models of male fertility. Male global SPAK knockout (SPAK–/–) and Sertoli cell-specific OSR1 gene knockout (SC-OSR1–/–) mice are fertile. But male global OSR1+/– gene mutations cause subfertility. Our data revealed that increased the phosphorylated (p) OSR1 expression in SPAK–/– testis tissue, suggested the compensatory effects of OSR1 and SPAK in male fertility. To dissect this effect, we generated SC-OSR1–/– and SPAK–/– double knockout (DKO) male mice. These adult male mice are infertile with defective spermatogenesis, presenting a SC-only-like syndrome. Disrupted meiotic progression and increased germ cell apoptosis occurred in the first wave of spermatogenesis. Impaired NKCC1 activity was noted. These results indicate that OSR1 and SPAK cooperatively regulate an NKCC1-dependent spermatogenesis a SC-restricted manner. ABSTRACT (DcR3) T cells play a central role in immune system, including immunoregulation and immunostimulation. The peripheral blood and decidua in unexplained recurrent spontaneous abortion patients revealed increased prevalence of T helper 17 (Th17) cells, suggesting an important role of The 17 cells in the pathogenesis of RSA. In this study, we investigated the modulatory effects of decoy receptor 3 (DcR3) in recurrent spontaneous abortion (RSA). We used hydrodynamic-based intravenous (IV) administration of DcR3 plasmid into female CBA/J mated male DBA/2 as the abortion-prone model to elucidate the physiological role of DcR3 on RSA. Our results revealed that DcR3 significantly reduced abortion rate in pregnant female CBA/J mice on d13.5. The expression of IL-17-producing CD4 T cells was decreased in the uterus of DcR3-treated mice. Our data suggested that DcR3 has potential as a suppressor of uterus inflammation in the abortion-prone model, which may be attributed to either direct inhibition of uterus inflammation or suppression of abortive Th17 cells. This study is mainly performed in the abortion-prone model. Application of DcR3 in unexplained recurrent spontaneous abortion patients needs further studies. This study provides a therapeutic effect of DcR3 in the abortion-prone model, suggesting its potential for treating women RSA.