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1
Shahidullah, B. Sara. "Hearing in the fetus". Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333792.
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Gannon, Benedict William. "Specific lgG antibody responses to the surface layer proteins of Campylobacter fetus subsp. fetus". Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424043.
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Mukhtar, Lenah. "Evaluation of the Genetic Differences Between Two Subtypes of Campylobacter fetus (Fetus and Venerealis) in Canada". Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24402.
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The pathogen Campylobacter fetus (CF) is classified into two subspecies, Campylobacter fetus subspecies fetus (CFF) and Campylobacter fetus subspecies venerealis (CFV). Even though CFF and CFV are genetically closely related, they exhibit differences in their host adaptation; CFF inhabits the gastrointestinal tract of both humans and several animal species, while classical CFV is specific to the bovine genital tract and is of particular concern with respect to international bovine trade regulation. Traditionally, differentiation between the two subspecies has been achieved using a limited number of biochemical tests but more rapid and definitive genetic methods of discrimination are desired. A recent study suggested that the presence of a genomic island only in CFV could discriminate between the two sub- species but this hypothesis could not be confirmed on a collection of isolates originating in Canada.
To identify alternative gene targets that would support accurate subspecies discrimination, this study has applied several approaches including suppression subtractive hybridization and whole genome sequencing supplemented with optical mapping. A subtractive hybridization screen, using a well-characterized CFV isolate recovered during routine screening of bulls in an Artificial Insemination center in western Canada and that lacked much of the genomic island and a typical Canadian CFF isolate, yielded 50 clones; characterization of these clones by hybridization screening against selected CF isolates and by nucleotide sequence BLAST analysis identified three potentially CFV-specific clones that contained inserts originating from a second genomic island. Further screening using a larger CF sample set found that only Clone #35 was truly CFV-specific. Optical maps (NcoI digest) of the Canadian CFF and CFV isolates used for the subtractive hybridization showed that certain regions of these genomes were quite distinct from those of two reference strains. Whole genome sequencing of these two isolates identified two target genes (PICFV5_ORF548 and CFF_Feature #3) that appear to be selectively retained in the two subspecies. Screening of a collection of CF isolates by PCRs targeting these three loci (SSH_Clone #35, PICFV5_ORF548 and CFF_Feature #3) supported their use for subspecies discrimination. This work demonstrates the complex genomic diversity associated with these CF subtypes and the challenge posed by their discrimination using limited genetic loci.
4
Moustafa, Moustafa. "Fetus safety in motor vehicle accidents". Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16308.
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Motor vehicle accidents are statistically the major cause of accidental severe injuries for pregnant women and fetuses fatality. Volunteers, post mortem human surrogates, anthropomorphic crash test devices and computational occupant models are used to improve human safety in motor vehicle accidents. However, due to the ethical issues, pregnant women and their fetuses cannot be used as volunteers or post mortem human surrogates to investigate the effects of crashes on them. The only anthropomorphic test device representing pregnant women is very limited in design and lacks a fetus. There is no computational pregnant occupant model with a fetus other than 'Expecting'. This thesis focuses on understanding the risk of placental abruption for pregnant drivers involved in road accidents, hence assessing the risk to fetus fatality. An extensive review of existing models in general and pregnant women models in particular is reported. The time line of successive development of crash test dummies and their positive effect on automotive passive safety design are examined. 'Expecting', the computational pregnant occupant model with a finite element uterus and a multibody fetus, is used in this research to determine the strain levels in the uteroplacental interface. External factors, such as the effect of restraint systems and crash speeds are considered. Internal factors, such as the effect of placental location in the uterus, and the inclusion and exclusion of a fetus are investigated. The head of the multibody fetus is replaced with a deformable head model to investigate the effects of a deformable fetus head on strain levels. The computational pregnant driver model with a fetus offers a more realistic representation of the response to crash impact hence provides a useful tool to investigate fetus safety in motor vehicle accidents. Seat belt, airbag and steering wheel interact directly with the pregnant abdomen and play an important role on fetus safety in motor vehicle accidents. The results prove that the use of a three-point seat belt with the airbag offer the greatest protection to the fetus for frontal crash impacts. The model without a fetus underestimates the strain levels. The outcome of this research should assist automobile manufacturers to address the potential safety issues at the design level.
5
Coe, Benjamin Lloyd. "Obesity a growing concern about fetal nutrition /". Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4636.
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Thesis (M.A.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 6, 2007) Vita. Includes bibliographical references.
6
Lam, Yung-hang. "Sonographic features of fetuses with homozygous [alpha]-thalassaemia-1 during early pregnancy". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23373295.
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Filho, Manoel Oliveira. "Laparoscopic ovarian transposition in human dead fetus". Universidade Federal do CearÃ, 2004. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=359.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorObjetivo: A Cirurgia VÃdeoendoscÃpica tem inicio no final do sÃculo vinte, como uma grande inovaÃÃo da medicina, porÃm sà recentemente tem sido explorado seu potencial. Os endoscÃpicos tem sidos utilizados atualmente para realizar uma variedade de procedimentos diagnÃsticos e terapÃuticos. A aquisiÃÃo de novos conhecimentos e habilidades sÃo exigidos pela tÃcnica que obriga, tanto ao novo cirurgiÃo como atà mesmo ao cirurgiÃo mais experiente, buscar conhecimentos, treinamentos, habilitaÃÃo e credenciamento no novo mÃtodo operatÃrio para que possa exercer a medicina cirÃrgica da atualidade. A videoendoscopia na ginecologia oncolÃgica ainda nÃo esta completamente definida, pois somente nos Ãltimos dez anos à que o desenvolvimento da cirurgia endoscÃpica de mÃnimo acesso tem tido uma marcante expansÃo nas suas aplicaÃÃes. A preservaÃÃo da funÃÃo ovariana nas mulheres jovens que tem cÃncer de colo uterino em estÃgio precoce, linfomas Hodgkin e nÃo Hodgkin e de carcinoma colo retal que necessitam submeter-se a radioterapia externa e interna, a videoendoscopia tem sido usada como mÃtodo cirÃrgico com a finalidade de minimizar os efeitos da radiaÃÃo, à um procedimento seguro e eficaz na preservaÃÃo da funÃÃo ovarina. O objetivo deste trabalho foi transpor os ovÃrios de cadÃver fetal para fora da regiÃo pÃlvica e reposicionÃ-los o mais alto possÃvel na parede lateral do abdÃmen, fixando-os com fios e grampos metÃlicos.
Objectives: Videoendoscopic surgery began at the end of twentieth century as a great innovation however; only in recent years its potential role has been explored. The endoscopes have been used to carry out a variety of diagnosis and therapeutic procedures. The acquisition of knowledge and habilities required by the technique obligates both the inexperienced surgeon and the experienced one, to seek information, training, qualification, and accreditation on new operative method in order to practice present time surgical medicine. Minimum access endoscopic surgery had an outstanding expansion on its applications for the past 10 (ten) years; due to this the Videoendoscopic is not totally defined within the oncologic gynecology. The preservation of ovarian function on young women that have precocious stage uterine colon cancer, Hodgkin lymphoma, Non-Hodgkin lymphoma and colon carcinoma â rectal that requires external and internal radiotherapy, the Videoendoscopic has been used as a surgical method in order to minimize the radiation effects, because it is a safe and effective procedure to preserve the ovarian function. The purpose of this work was to transpose the ovaries in human corpse fetus to outside the pelvic region and replace them in the highest possible point on the abdomen sidewall. Methods: Videolaparoscopic fixation of the ovaries with purse-string suture and clips. Two 18.9 in. (48cm) and 19.7 in (50cm), weighting 6.8 and 7.3 pounds (3.1 and 3.3 (kilograms) respectively, human fetus corpses were used. All the equipments and Videoendoscopic surgery instruments were used The usage of human material as a way of training provided the activity the possibility to carry out in similar conditions and of identical anatomy, whenever coming across surgery with alive individuals. Conclusion: the purpose of this work represents a perfectly feasible method of carrying out, training practice importance and surgeon improvement for the ovarian function preservation.
8
Fernandes, Manuela Maio Graça. "Tetralogy of fallot: From fetus to adult". Master's thesis, Faculdade de Medicina da Universidade do Porto, 2009. http://hdl.handle.net/10216/53605.
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Fernandes, Manuela Maio Graça. "Tetralogy of fallot: From fetus to adult". Dissertação, Faculdade de Medicina da Universidade do Porto, 2009. http://hdl.handle.net/10216/53605.
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Cheong, Kah-bik. "The use of volumetry by three-dimensional ultrasound in the first trimester". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43572339.
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Meffe, Filomena. "Optimal delivery method for the fetus with meningomyelocele". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28750.pdf.
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Wigmore, Kip. "The primordial germ cells of the goat fetus". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ43237.pdf.
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Doherty, N. Nicola. "Neurobehavioural effects of maternal diabetes on the fetus". Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388050.
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McGeehan, M. S. "Is a neurological assessment of the fetus possible". Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395374.
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Wong, Ho-man Simon. "Evaluation of a new fetal biometric normogram of the Hong Kong Chinese". Click to view the E-thesis via HKUTO, 2010. http://sunzi.lib.hku.hk/hkuto/record/B43958709.
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16
Romano, Juan Eduardo. "Early pregnancy diagnosis and embryo/fetus mortality in cattle". Texas A&M University, 2004. http://hdl.handle.net/1969.1/3125.
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Pregnancy diagnosis by transrectal ultrasonography (using a 5 MHZ linear
probe) presented the maximum sensitivity and negative predictive values at day 26 and
day 29 after estrus in heifers and cows, respectively.
Palpation per rectum using the fetal membrane slip for pregnancy diagnosis did
not increase embryo/fetus mortality when compared with a positive control group of
non-palpated females. The use of a controlled randomized block design was a useful
approach to study this problem. Blocking for category and number of embryos allowed
us to remove these confounding factors.
Factors that affected pregnancy loss during the first four months of pregnancy
were: period of pregnancy, age of the animal, number of previous lactations and number
of embryos. Pregnancy loss was higher during the embryonic than fetal periods.
Spontaneous embryo/fetal mortality increased with the age of the animal and lactation
number. The risk of spontaneous embryo/fetus mortality was higher in twin than in
single pregnancies.
Two types of embryo/fetus mortality were noted: Type I and Type II. Type I was
characterized by presence of positive fetal membrane slip by palpation per rectum, signs
of degeneration by transrectal ultrasonography and persistence of a functional corpus
luteum. The uterus took approximately 3 weeks to be noted clean by transrectal
ultrasonography and the animals showed estrus one month after the conceptus was
diagnosed dead. Type II was characterized by absence of positive signs of pregnancy by
palpation per rectum, absence of signs of degeneration by transrectal ultrasonography
and absence of a functional corpus luteum.
Pregnancy loss in nuclear transfer derived embryos was higher compared to in
vivo derived embryos produced by artificial insemination. Pregnancy loss occurred
mainly during the transition from the embryonic to the fetal period. Embryo/fetus
mortality detected was Type I. Progesterone produced by the corpus luteum was noted at
pregnancy levels for approximately two weeks after embryo/fetus death. Protein B, a
hormonal placental marker, was maintained at pregnancy levels for approximately 3
weeks after embryo/fetus death. No differences in the levels of the two hormones were
noted when comparing females with dead or live conceptuses.
17
Simpson, John Munro. "Echocardiographic evaluation of cardiac function in the human fetus". Thesis, King's College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248408.
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Hagan, Donna Marie. "Neuroendocrine regulation of hypothalamo-pituitary function in the fetus". Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/28175.
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During fetal development there is a progressive maturation of the hypothalamo-pituitary-adrenal (HPA) axis which is responsible for co-ordinated fetal maturation and the onset of birth. The aim of this thesis is to investigate the neuroendocrine regulation of the developing HPA axis. The first approach was to investigate the role of putative neurotrophic factors in the functional maturation of hypothalamic arginine vasopressin (AVP) neurons. The role of AVP in the release of adrenocorticotropic hormone (ACTH) has been extensively demonstrated but little is known about the factors controlling the development of AVP neurons. The objective of this study was to chart the growth and development of AVP neurons in cell culture in response to various neurotrophic factors. Functional maturation of the neurons was assessed in terms of the secretory response to potassium-induced depolarisation whilst development of neuronal morphology was to be monitored by immunocytochemistry. Fetal rat hypothalamic neurons were cultured in the presence and absence of insulin-like growth factor-1 (IGF-1), which has been implicated as a putative neurotrophic factor, for periods of up to 20 days. IGF-1 had no significant effect on either basal or stimulated levels of AVP secretion, suggesting that AVP neurons do not appear to be the specific target population for IGF-1 within the developing fetal hypothalamus. Despite extensive screening of several different antibodies, we were unable to specifically identify AVP neurons in culture by immunocytochemistry. These results demonstrate the existence of an endogenous inhibitory system regulating the release of ACTH, α-MSH and prolactin from the fetal pituitary gland. However, these results do not support the hypothesis that peptides released upon removal of the inhibitory dopaminergic tone are capable of eliciting the secretion of cortisol from the fetal adrenal gland.
19
Jones, Karen. "A biokinetic model for Cesium-137 in the fetus". Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/16764.
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Gallagher, Francis J. "Spectral analysis of blood velocity in the human fetus /". Online version of thesis, 1995. http://hdl.handle.net/1850/11811.
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Cheong, Kah-bik, i 張嘉碧. "The use of volumetry by three-dimensional ultrasound in the first trimester". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43572339.
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Morey, Adrienne Louise. "The pathogenesis of parvovirus B19 infection in the human fetus". Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316848.
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McCooke, H. B. "Carotid chemoreceptor sensitivity in the fetus and in the neonate". Thesis, University of Reading, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376794.
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Cook, Andrew Charles. "The anatomy of left heart hypoplasia in the human fetus". Thesis, King's College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408804.
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David, A. L. M. "Development of ultrasound-guided gene therapy to the sheep fetus". Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444686/.
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Fetal gene therapy may treat genetic diseases before significant organ damage, target stem cell populations and avoid immune sensitisation. Candidate diseases include cystic fibrosis, haemophilia and lysosomal storage disorders. This thesis developed ultrasound-guided delivery of viral vectors to the sheep fetus for treatment of these diseases. For haemophilia B treatment we delivered adenovirus vectors containing the p-galactosidase reporter gene (adlacZ) or the human factor IX gene (adhFIX) by ultrasound guidance to the early gestation sheep fetus, when it is considered to be pre-immune. Intraperitoneal injection allowed the earliest time point for gene delivery, achieved the highest hFIX levels and the most localised p-galactosidase expression. Therapeutic hFIX levels were detected after intramuscular and intra-amniotic delivery suggesting that these are potentially alternative sites for therapeutic gene expression. For each route examined, no humoral immune response was observed to the transgene, although antibodies to the adenovirus vector were identified. We achieved intravascular delivery via umbilical vein injection therapeutic hFIX levels were detected. We developed ultrasound-guided transthoracic injection of the mid-gestation fetal trachea for cystic fibrosis treatment, p-galactosidase expression, measured by ELISA, was low after delivery of adlacZ vector alone, but increased 10 fold when the vector was complexed with DEAE dextran. Pretreatment of the fetal airways with sodium caprate increased expression by 90 fold the effect of the two agents was synergistic. Perflubron instillation following vector injection redistributed transgene expression from the large to the small airways. We developed ultrasound-guided fetal intragastric injection and achieved widespread transgene expression throughout the gastrointestinal epithelia after adlacZ vector delivery. For brain manifestation of lysosomal storage disorders we injected adlacZ vectors to the fetal ventricles under ultrasound guidance. Transduction of the choroid plexus was seen. Future application of integrating vectors such as lentivirus may allow for long term therapeutic correction and induce immune tolerance to the transgene.
26
Karagiannis, Georgios. "First trimester prediction of the 'small for gestational age' fetus". Thesis, King's College London (University of London), 2016. https://kclpure.kcl.ac.uk/portal/en/theses/first-trimester-prediction-of-the-small-for-gestational-age-fetus(bc6f0017-55bf-4d26-b1fe-f2e6cd0a87f5).html.
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Objective: In this thesis, we investigate the association between maternal factors, biophysical and biochemical markers and the delivery of small-for-gestational-age (SGA) neonates in the absence of preeclampsia (PE) at 11–13 weeks’ gestation. We evaluate their performance as predictors of SGA, both in isolation and combined, in an effort to develop a model for the prediction of SGA in the first trimester of pregnancy. Methods: Screening study in 1,536 SGA and 31,314 non-SGA pregnancies based on maternal characteristics, fetal nuchal translucency (NT) thickness, serum pregnancy-associated plasma protein-A (PAPP-A) and free β-human chorionic gonadotrophin (β-hCG). We also measured mean arterial pressure (MAP), uterine artery pulsatility index (PI) and performed case-control studies for measurement of maternal serum concentration of placental growth factor (PLGF), placental protein 13 (PP13), A Disintegrin And Metalloprotease (ADAM12), Soluble endoglin (sENG) and thyroid hormones (thyroid stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxine (FT4)). Regression analysis was used to develop a model for the prediction of SGA. Results: In the SGA group, uterine artery PI and MAP were increased, serum PAPP-A, free β-hCG, PLGF, PP13, and ADAM12 and fetal NT were decreased while sENg and thyroid hormones were not significantly altered. At a false positive rate of 10%, the estimated detection rate by a combination of maternal factors and biophysical and biochemical markers at 11–13 weeks was 73% for SGA requiring delivery before 37 weeks and 46% for those delivering at term. Conclusions: Half of the pregnancies with SGA neonates in the absence of PE could potentially be identified at 11–13 weeks.
27
Popelyuk, O. M. V. "Aspects of human larynx formation in the development of fetus". Thesis, БДМУ, 2017. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/16798.
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Nitsovych, I. R. "Intrauterine infection of the fetus at different stages of pregnancy". Thesis, БДМУ, 2022. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/19737.
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林勇行 i Yung-hang Lam. "Sonographic features of fetuses with homozygous [alpha]-thalassaemia-1during early pregnancy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31981744.
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Hoelle, Katharina. "The role of System A amino acid transport in fetal growth and development". Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609768.
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Masoller, Casas Narcís. "Estudi del desenvolupament cerebral en els fetus afectes de cardiopatia congènita". Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/398944.
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Les CC són les malformacions congènites més freqüents i la principal causa de mortalitat per anomalia congènita durant el primer any de vida. Durant les últimes dècades, l’augment de la supervivència com a conseqüència de la millora de les tècniques quirúrgiques i de les mesures de suport postoperatòries ha fet desviar l’atenció cap a l’elevada xifra de morbiditat neurològica que presenten aquests infants.
Inicialment, aquesta morbididitat neurològica era atribuïda a la cirurgia cardíaca i les seves complicacions, però en els últims anys ha aparegut cada vegada més evidència a favor de que els nadons amb CC ja presenten anomalies cerebrals immediatament després de néixer i abans de la cirurgia cardíaca. D’aquesta manera s’ha focalitzat l’atenció cap a un possible origen prenatal de la lesió cerebral que presenten aquest infants. Aquest concepte, conegut com "programació fetal", és un dels enfocs més importants de cares a la prevenció de les malalties durant l’edat adulta. El desenvolupament cerebral durant la vida fetal és un procés molt complex que requereix un equilibri adequat en l’aportació d’oxigen i nutrients. Les condicions adverses durant l'embaràs, com per exemple la presència d’una CC, poden condicionar un desenvolupament cerebral anormal que posteriorment pot acabar desembocant en els diferents tipus i graus de morbiditat neurològica que presenten els nadons i infants amb CC.
En aquesta tesi hem demostrat que és possible identificar canvis en el desenvolupament cerebral dels fetus amb CC des d’etapes molt precoces de la gestació fins a terme utilitzant diferents tècniques d’imatge (ecografia i ressonància magnètica). A més hem demostrat com, a part del tipus de CC, existeixen altres variables (biometries cefàliques i variables de l’estudi Doppler) que ens poden ajudar a identificar de manera molt precoç quins fetus amb CC presentaran més risc de presentar alteracions en el desenvolupament cerebral.
La informació presentada obre les portes per la introducció d’aquestes variables dins de l’avaluació inicial de les CC, en el moment de diagnòstic, permetent així identificar de manera precoç els fetus amb més risc de desenvolupar anomalies del sistema nerviós central que condicionin posteriorment l’aparició d’alteracions en el neurodesenvolupament.
La identificació precoç dels fetus amb risc de presentar un neurodesenvolupament anormal permetrà, per una banda, millorar de manera significativa l’assessorament familiar en el moment del diagnòstic de la CC i, per altre banda, permetrà iniciar intervencions (programes d’estimulació precoç) per tal de millorar el resultat neurològic final d’aquests infants.Congenital heart disease (CHD) are the most common congenital malformations and the main cause of mortality for congenital anomaly during the first year of life. During the past decades, the increase of survival of these babies, as a result of improved surgical techniques and postoperative support measures, has diverted the attention to the high number of these children that presents neurological impairment. Initially, this neurological morbidity was attributed to cardiac surgery and its complications, but in recent years several studies has showed that babies with CHD already have brain abnormalities immediately after birth and before cardiac surgery. These findings have focused the attention on a possible prenatal origin of brain injury in these babies. In this thesis we demonstrated that it is possible to identify changes in brain development of fetuses with CHD from very early stages of pregnancy to term using different imaging techniques (ultrasound and MRI). We have also shown how, regardless of the type of CHD, there are other variables (cephalic biometry and brain Doppler) that can help us to identify which fetuses with CHD present greater risk of abnormal brain development. From a clinical perspective, the use of specific brain predictors might be incorporated as part of the comprehensive assessment at the time of clinical diagnosis of CHD. An individualized prediction of the risk of abnormal neurodevelopment could improve parental counseling and facilitate early-life interventions that have been shown to improve brain development in other infants at risk.
32
Smith, L. A. "The acute effects of smoking on the behaviour of the fetus". Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492269.
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Previous research shows that fetuses of smokers exhibit reduced levels of spontaneous movement and abnormal patterns of habituation. However, much of this research has been completed on fetuses over 30 weeks gestational age, considering either the chronic or the acute effects of smoking. The present research incorporated three main studies. The first compared the acute with the chronic effects of smoking on spontaneous behaviour in fetuses at 14, 18 and 22 weeks gestational age. The second and third compared the acute with the chronic effects of smoking on fetal habituation patterns at 30 and 34 weeks gestational age. A between groups design was implemented for all studies. Study 1 monitored spontaneous fetal behaviour. Studies 2 and 3 monitored fetal reaction to a sound stimulus which was repeated ten times at 30 weeks and 20 times at 34 weeks gestation. Study 1 revealed that fetuses exposed to acute maternal smoking exhibited significantly less breathing and general body movements than both the chronicsmoking and non-smoking groups. They also exhibited significantly more startle movements. Study 2 revealed that at 30 weeks gestation, fetuses chronically exposed to smoking expressed abnormal patterns ofresponding to stimuli when compared with the fetuses of the non-smoking group, but only over the first 4 trials. Study 3 revealed that, at 34 weeks gestation, fetuses acutely exposed to smoking expressed abnormal patterns of responding compared to chronically exposed fetuses. Supplied by The British Library - 'The world's knowledge' l The findings indicate that, from 14-22 weeks gestational age, fetuses are more affected by the acute than the chronic effects of smoking. At 30 and 34 weeks gestational age, fetuses exposed to chronic-smoking are overly sensitive to sound stimuli whereas fetuses exposed to acute-smoking are under-sensitive. Differences in behaviour between the smoking groups and the non-smoking group suggest the possibility that exposure to maternal smoking impairs neurological functioning. This may be an indication oflater neuro-behavioural difficulties in child and adult-hood.
33
Lee, Brenda 1974. "Prostaglandin D2 and the development of sleep in the ovine fetus". Monash University, Dept. of Physiology, 2000. http://arrow.monash.edu.au/hdl/1959.1/8924.
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Lunshof, Maria Simone. "Circadian rhythms in the normal and growth-retarded fetus and infant". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2000. http://dare.uva.nl/document/81110.
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Grognono-Thomas, Rosemary. "The role of (S)-layer proteins in ovine Campylobacter fetus infections". Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312325.
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鄧莉莉 i Lee-lee Jade Teng. "Identification of thermo-tolerant campylobacter fetus by 16S ribosomalRNA gene sequencing". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B3196994X.
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Jackson, Courtney M. "Chorioamnionitis induces systemic and mucosal immune responses in the developing fetus". University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592818915104982.
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Wilcox, Gavin Rutledge. "Haematological processes occurring in the fetus with Doppler-defined placental insufficiency". Thesis, The University of Sydney, 1991. https://hdl.handle.net/2123/26400.
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Doppler-defined placental insufficiency may be diagnosed by measurement of the systolic: diastolic ratio of the umbilical artery flow velocity waveform and is associated with a number of perinatal complications including perinatal mortality, intrauterine growth retardation, pregnancy-induced hypertension and fetal distress in labour. It is known that the changes seen in the umbilical artery waveform are caused by a reduction in the number of arterioles and small arteries in the tertiary placental villi but the processes that precede and accompany these placental vascular changes remain obscure. The aim of the work described in this thesis is to extend current knowledge of the pathophysiology of placental insufficiency by examining various haematological processes that may cause or accompany the placental vascular changes seen in this disease. Infants with placental insufficiency were categorised as moderately or severely affected according to the degree that their umbilical artery waveforms differed from normal. A control group of infants with normal umbilical artery waveforms was also defined. Fetal blood was collected from the umbilical cord or the placenta at the time of delivery. The following haematological parameters were assessed and compared in the three groups of infants: erythrocyte number, size and related parameters, platelet number, the plasma glycocalicin concentration which may be used to estimate platelet lifespan, the coagulation status and the plasma concentration of 6keto-prostaglandin Fla, a major hydrolytic product of prostacyclin. In addition an immunoradiometric assay for glycocalicin was developed and characterised and the effects of maternal ingestion of low-dose aspirin on the production of thromboxane 82 by fetal platelets and on the placental production of thromboxane B2 and 6-keto-prostaglandin Fla were measured.
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Fahmy, Dina Mohamed Mahmoud. "The Investigation of the Chemotaxis Signal Transduction Pathway of Campylobacter Fetus". Thesis, Griffith University, 2014. http://hdl.handle.net/10072/367478.
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Campylobacter fetus is recognized as an important animal and human pathogen. Chemotaxis and motility have been identified as important virulence factors associated with C. jejuni colonisation. This study established that chemoreceptor and chemotaxis signal transduction cascade genes of C. fetus subsp. fetus 82-40 showed high level of similarity to that in C. jejuni and appears to include sixteen diverse transducer-like protein (tlp) genes that are similar to nine of the twelve tlp genes in the C. jejuni NCTC 11168 with a percent identity ranging from 15 to 50%. Sixteen putative C. fetus 82-40 tlp genes belong to three classes: A, B, and C, as well as an aerotaxis gene, based on their predicted structure. C. fetus subsp. fetus 82-40 chemoreceptor and chemotaxis signal transduction pathway genes have close phylogenetic relationship of chemotaxis genes between Campylobacteraceae and Helicobacteraceae.Thesis (Masters)
Master of Philosophy (MPhil)
Institute for Glycomics
Science, Environment, Engineering and Technology
Full Text
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Alves, Telma Maria. "Produção e caracterização de anticorpos monoclonais contra Campylobacter fetus subsp. Venerealis". Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/MASA-7BANTZ.
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Myeloma cells Sp2/0-Ag14 and spleen cells from BALB/c mouse immunized with sonicated Campylobacter fetus subsp. venerealis NCTC 10354 were fused with polyethylene glycol (PEG) for the production of monoclonal antibodies (MAb's). Clones were obtained by limiting dilution and screened for specific MAb's to C. fetus subsp. venerealis NCTC 10354 by indirect ELISA and western blot against a panel of bacteria: C. fetus subsp. venerealis NCTC 10354, C. fetus subsp fetus ADRI 1812, C. sputorum biovar sputorum LMG 6647, C. lari NCTC 11352, and Arcobacter skirrowii LMG 6621 for the ELISA and C. fetus subsp. venerealis NCTC 10354 and C. sputorum biovar sputorum LMG 6647 for the western blotting. Fifteen clones producing MAb's anti C. fetus subsp. venerealis of the IgM (1) and IgG (14) classes were further screened for species-specificity. Four clones of the 15 obtained were producers of species-specific MAb's, 2 were specific for C. fetus subsp venerealis and 2 specific for C. fetus subsp fetus. None of the clones were reactive against C. sputorum biovar sputorum LMG 6647. All clones recognized a protein with molecular mass of approximately 148 kDa from lised C. fetus subsp. venerealis NCTC 10354.Para a produção de anticorpos monoclonais contra Campylobacter fetus subsp. venerealis foram utilizadas as linhagens de células de mieloma Sp2/0-Ag14 e células de baço de camundongos BALB/c imunizados com sonicado de C. fetus subsp. venerealis NCTC 10354. A detecção dos anticorpos monoclonais foi realizada por ELISA indireto utilizando antígeno sonicado de C. fetus subsp. venerealis NCTC 10354. A clonagem foi realizada por diluição limitante e os clones foram caracterizados por ELISA indireto utilizando um painel de bactérias sonicada escolhidas em função da prevalência e habitats: C. fetus subsp. venerealis NCTC 10354, C. fetus subsp fetus ADRI 1812, C. sputorum biovar sputorum LMG 6647, C. lari NCTC 11352 e Arcobacter skirrowii LMG 6621; e no "western blotting" utilizando antígenos sonicados de C. fetus subsp. venerealis NCTC 10354 e C. sputorum biovar sputorum LMG 6647. Foram obtidos 15 clones produtores de anticorpos anti C. fetus subsp. venerealis das classes IgM (1) e IgG (14). Quatro clones dentre os 15 clones obtidos foram produtores de anticorpos monoclonais espécie-específicos: dois clones reagiram com maior especificidade contra C. fetus subsp venerealis NCTC 10354 e dois clones reagiram com maior especificidade contra C. fetus subsp fetus ADRI 1812. Nenhum dos clones reagiu contra C. sputorum biovar sputorum LMG 6647, comprovando a especificidade dos anticorpos monoclonais testados. Todos os clones reconheceram uma proteína de massa molecular de aproximadamente 148 kDa no sonicado de C. fetus subsp. venerealis NCTC 10354.
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Stynen, Ana Paula Reinato. "Detecção de Campylobacter fetus em lavados prepuciais de touros pela PCR". Universidade Federal de Minas Gerais, 2000. http://hdl.handle.net/1843/BUDB-8BQGN8.
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A PCR based on the 23S rDNA sequence was developed for the detection of C. fetus from preputial washings of bulls. Three extraction methods were evaluated for the extraction of DNA in preputial washings: the guanidiniu, tiocynate, the alkaline lysis and the Chelex 100 methods. To determine the specificity of the test, Camppylobacter sp, Helicobacter sp and Escherichia coli reference strains were submitted to PCR. Preputial washings of 47 bulls from one farm with a positive diagnosis of Bovine Genital Campilobactosis were tested by PCR and direct fluorescent antibody test (DFAT). Only C. fetus subps, fetus and C.fetus subps, venerealis were amplified by PCR and the detection limit was 3,8 x 10² CFU/ml of C. fetus. The specificity of the amplified product was confirmed by restriction analysis with Avall. Eight bulls were considered infected by the two tecniques, but three animals were only positive by PCR and seven only by DFAT. The present PCR assay was suitable to detect C. fetus in preputial washing samples.Uma reação em cadeia da polimerase (PCR) baseada na seqüência 23S do DNA ribossomal foi desenvolvida para detecção de C. fetus em lavados prepuciais de touros. Foram avaliados três métodos de extração de DNA nos lavados prepuciais: o método do tiocianato de guanidina, o da lise alcalina e do Chelex 100. Para determinar a especificidade do teste, amostras de referência de Campylobacter SP, Helicobacter SP e Escherichia coli forma submetidas a PCR. Lavados prepuciais de 47 touros de uma propriedade com diagnóstico de Campilobacteriose Genital Bovina foram testados pela PCR e imunofluorescência direta (IFD). Somente amostras de C. fetus subps. venerealis e C. fetus subps. fetus foram amplificadas e o limite de detecção da PCR em lavado prepucial foi de 3,8 x 102 CFU/ml de C. fetus. A especificidade do produto amplificado foi confirmada pela análise de restrição frente à enzima Ava II. Oito touros foram considerados infectados pelas duas técnicas, porém três animais só foram positivos à PCR e sete somente na IFD. A PCR padronizada mostrou-se eficiente na detecção de C. fetus em amostras de lavado prepucial, nas condições trabalhadas.
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Wippermann, Wolf. "Diaplazentare Deoxynivalenolintoxikation bei Schweinefeten. Lassen sich am 70. Trächtigkeitstag histomorphologisch und immunhistologisch diagnostisch verwertbare Befunde erheben?" Doctoral thesis, Universitätsbibliothek Leipzig, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-67849.
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Koch, Jill Marie. "Periconceptional treatment with growth hormone alters fetal growth and development in sheep". Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5713.
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Thesis (Ph. D.)--West Virginia University, 2008.Title from document title page. Document formatted into pages; contains ix, 128 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
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Andrews, David C. "Breathing control and thermoregulation in the developing lamb". Thesis, Oxford Brookes University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359674.
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Ahmed, Mohamed Abdelrahman. "Immunological study of mouse embryonic development in relation to major histocompatibility complex". Thesis, University of Essex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343267.
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ANDREU, MARIE-RITA. "Septicemies a campylobacter fetus : necessite de rechercher une lesion digestive ; a propos de sept observations". Nantes, 1994. http://www.theses.fr/1994NANT004M.
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Sibley, Colin. "The nutrient exchange phenotype of the placenta in fetal growth restriction : characterization, adaptation and regulation". Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-nutrient-exchange-phenotype-of-the-placenta-in-fetalgrowth-restriction-characterization-adaptation-and-regulation(35a27da9-ad7c-4e7e-8e91-8742304a5c9c).html.
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An essential function of the placenta is the exchange of nutrients, and wasteproducts of fetal metabolism, between mother and fetus. The placenta thereforeplays a key role in determining fetal growth and size at birth. Fetal growthrestriction (FGR) is a complication affecting around 5% of pregnancies. Thereare several possible causes of FGR but the most common in the Western world isplacental dysfunction. The FGR baby is at much greater risk of stillbirth andneurodevelopmental morbidities than the normally grown baby. Furthermore, thesmaller baby per se has an increased risk of a range of morbidities as an adult.The thrust of the work covered in this thesis was to improve understanding of theabnormalities in placental exchange physiology associated with FGR. The goalwas (and is) to develop new placental diagnostic biomarkers for the disease andnew treatments based on improving placental function.The first tranche of work described showed that there are specific changes intransporter activities in the placenta in FGR. My colleagues and I showed thatSystem A amino acid transporter activity in the microvillous plasma membrane(MVM) of the syncytiotrophoblast (transporting epithelium of the placenta) isreduced, per mg membrane protein, and that this reduction is related to theseverity of the disease. This contrasted with our observation in normal pregnancythat MVM System A activity, per mg protein, is inversely related to size of the babyat birth, and first suggested the concept of placental adaptation to fetal growthdemand. We, and others, went on to show that a number of other transporters inthe syncytiotrophoblast are altered in FGR. However, not all transporters areaffected and at least one is upregulated. This led me to hypothesise that some ofthese changes are causal to FGR and some are responses, or adaptations, toabnormal fetal growth. The direct causes of transporter activity changes are notknown but our work, and that of others, suggests that glucocorticoids play a role.We also showed that transporter activities in the placenta are affected in othercomplications where fetal growth is aberrant. Furthermore, we provided evidencethat denuded areas of the syncytiotrophoblast might be the morphologicalcorrelate of a route of passive transfer of hydrophilic solutes across the placenta.Our studies in a mouse model of FGR suggest that abnormalities in such aparacellular route may be part of the placental dysfunction in the disease.In the final group of publications of this thesis I describe work showing gestationalchanges in placental transporter activities. I suggest that these are primarilyregulated to maintain fetal growth trajectory, but may also provide for specificnutrient demands at particular times in gestation. This explanation was supportedby work with genetically modified mice showing experimentally that placentaltransporter activity is regulated, or adapted, in relation to fetal growth demand. Itappears from several studies described here that there is a matching of fetalgrowth demand and placental nutrient supply. However, other work shows that thematernal nutritional environment does modify this matching.The studies described here have led to three ongoing lines of investigation: (1)applying knowledge of placental phenotypes of FGR to assist in early diagnosis ofwomen at risk; (2) using mouse models of FGR to test drugs for treating thedisease in humans; (3) investigations into the nature of the fetal nutrient demandsignal(s) to the placenta, and whether these signals are altered in FGR.
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O'Regan, Shaun. "A critical evaluation of the accuracy of foetal age estimation by sonographic biometry at Ipswich Hospital". Thesis, Queensland University of Technology, 1991. https://eprints.qut.edu.au/35980/1/35980_O%27Regan_1991.pdf.
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Diagnostic Ultrasound plays an important role in the
management of the obstetric patient, particularly in
relation to the estimation of foetal age in cases of
clinical uncertainty. The sonographic determination of
foetal maturity is based on the correlation of ultrasonic
measurements of selected anatomical parameters
with age estimates in biometric nomograms. The
prediction of foetal age at Ipswich General Hospital has
been based on biometric models developed by Hadlock. 45
The accuracy of these models in predicting foetal age in
patients at Ipswich Hospital is evaluated. Significant
errors in predicted foetal age are revealed and factors
contributing to these errors are highlighted.
Biometric models which more accurately predict foetal
age in the obstetric patient population at Ipswich
Hospital are developed by regression analysis of data
derived from a study sample of 346 patients with known
gestational age and normal foetal growth.
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Mademont, Soler Irene. "Estratègies de diagnòstic genètic en fetus amb malformacions congènites. Correlació genotip-fenotip". Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/120098.
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Les alteracions cromosòmiques constitucionals representen una de les principals causes d’anomalies congènites a la població, i el seu diagnòstic durant l’etapa prenatal és el principal objectiu de la majoria de procediments invasius que es realitzen durant l’embaràs. Actualment, el cariotip convencional és el gold standard del diagnòstic citogenètic prenatal, però els avanços tecnològics dels últims anys han portat al desenvolupament de tècniques de citogenètica molecular que ofereixen característiques molt atractives, la principal de les quals és l’elevada resolució. Donat que el paper que han de tenir aquestes tècniques durant l’etapa prenatal encara no està ben definit, els objectius de la present tesi han estat: a) determinar el potencial diagnòstic i la utilitat del cariotip i les tècniques de citogenètica molecular Fluorescent In Situ Hybridization (FISH), Multiplex Ligation-dependent Probe Amplification (MLPA) i Chromosomal Microarray-based Analysis (CMA) en diagnòstic prenatal, especialment per a l’estudi de gestacions amb troballes ecogràfiques; i b) valorar la necessitat de modificar els procediments actuals de diagnòstic citogenètic prenatal.
En primer lloc, s’han revisat els resultats dels 29.883 cariotips en líquid amniòtic realitzats entre 1998 i 2009 a l’Hospital Clínic de Barcelona. Els resultats obtinguts corroboren que el cariotip és una eina efectiva i robusta per a l’obtenció del cariotip fetal, revelant alteracions cromosòmiques en el 2,9% de les gestacions que es sotmeten a un procediment invasiu. La translucidesa nucal incrementada i les anomalies ecogràfiques destaquen com a indicadors excel•lents d’anomalia cromosòmica.
En segon lloc, s’ha avaluat la utilitat de l’MLPA subtelomèrica per a l’estudi de gestacions amb troballes ecogràfiques i cariotip normal. Dels 229 fetus analitzats, 3 presentaven desequilibris subtelomèrics críptics (1,3%). Donat que la freqüència d’aquests desequilibris és baixa, i a més la correlació genotip-fenotip observada és pobra, l’MLPA subtelomèrica no sembla ser una eina crucial per a l’estudi d’aquestes gestacions.
D’altra banda, s’ha estudiat la idoneïtat de reemplaçar els estudis de FISH de la regió 22q11.2 per kits d’MLPA dissenyats per a l’estudi d’aquesta regió i altres regions genòmiques associades a cardiopaties. S’han analitzat mitjançant aquests kits 55 gestacions amb troballes cardíaques, cariotip normal i estudi de FISH negatiu per a la microdeleció típica de 22q11.2, i no s’ha detectat cap anomalia. Aquest fet, juntament amb que l’MLPA presenta una taxa de repetició i de no obtenció de resultats superiors a la FISH, i que generalment requereix cultiu cel•lular, indica que la FISH hauria de seguir sent la tècnica d’elecció per a l’estudi de fetus amb troballes cardíaques (enfront l’MLPA).
També s’ha volgut determinar la freqüència dels diferents tipus d’alteracions cromosòmiques, tant microscòpiques com críptiques, en fetus amb troballes ecogràfiques cardíaques. L’anàlisi retrospectiu dels resultats obtinguts en el període 2009-2011 a l’Hospital Clínic de Barcelona en aquest grup de gestacions (N=276) ha revelat una freqüència d’anomalies cromosòmiques microscòpiques i casos de Síndrome de la deleció cromosòmica 22q11.2 del 15,9% i 6,4%, respectivament; uns resultats que corroboren la forta associació existent entre troballes ecogràfiques cardíaques i anomalies cromosòmiques. A més, aquesta associació varia significativament en funció del tipus de troballa ecogràfica cardíaca i de la presència d’anomalies extracardíaques. D’altra banda, s’han analitzat mitjançant array CGH 51 fetus amb troballes ecogràfiques cardíaques, cariotip normal, i sense estudi o resultat de FISH negatiu per a la Sd. de la deleció cromosòmica 22q11.2. En aquest grup de gestacions, la taxa de detecció de variants en número de còpia patogèniques ha estat del 2%, i no s’han detectat variants de significat clínic incert. Si en la nostra sèrie de 276 gestacions amb troballes ecogràfiques cardíaques s’hagués utilitzat l’estratègia QF-PCR + CMA enlloc de cariotip, totes les anomalies cromosòmiques amb repercussió clínica clara diagnosticades per citogenètica convencional s’haguessin identificat, s’haguessin detectat els casos de delecions de 22q11.2, i s’hagués incrementat un 2% el nombre de casos diagnosticats. Per tant, aquests resultats mostren el potencial de les plataformes de microarray per al diagnòstic prenatal de fetus amb troballes ecogràfiques cardíaques.
Finalment, s’han utilitzat les tècniques de citogenètica molecular FISH, MLPA i/o CMA per a la caracterització de 6 alteracions cromosòmiques visibles al cariotip però de difícil caracterització per citogenètica convencional. En tots els casos, la utilització d’aquestes tècniques ha contribuït a la correcte descripció de l’alteració identificada, posant de manifest la seva utilitat quan s’utilitzen de forma complementària al cariotip.
L’elaboració d’aquesta tesi i la literatura recentment publicada evidencien la necessitat d’un nou plantejament dels protocols clínics de diagnòstic citogenètic prenatal, especialment en relació a la utilització de plataformes de microarray en diagnòstic prenatal.Strategies for genetic diagnosis of fetuses with congenital malformations. Genotype-phenotype correlations. Constitutional chromosomal abnormalities represent one of the main causes of congenital abnormalities in the population, and their diagnosis during pregnancy is the main objective of most invasive procedures. Nowadays, conventional karyotyping is the gold standard for prenatal cytogenetic diagnosis, but recent technological advances have led to the development of molecular cytogenetic techniques which offer much higher resolution. Since there is still not a consensus on the role of these techniques in prenatal diagnosis, the goals of the present PhD work have been: a) to determine the diagnostic potential and usefulness of karyotype and molecular cytogenetic techniques Fluorescent In Situ Hybridization (FISH), Multiplex Ligation-dependent Probe Amplification (MLPA) and Chromosomal Microarray-based Analysis (CMA) in prenatal diagnosis, especially in pregnancies with ultrasound findings; and b) to establish the need for modifications in current prenatal cytogenetic diagnostic protocols. The results obtained: - Corroborate the effectiveness and robustness of conventional karyotyping. The observed detection rate of chromosomal abnormalities in 29,883 consecutive amniotic fluid samples has been 2.9%, with increased nuchal translucency and ultrasound abnormalities being excellent indicators for chromosomal abnormalities. - Suggest that subtelomeric screening in pregnancies with ultrasound findings and normal karyotype is not a crucial tool, as detection rate of subtelomeric imbalances is low (1.3%; 3/229), and genotype-phenotype correlations are poor. - Reveal that FISH of 22q11.2 region is preferred to MLPA kits specific for this chromosome region and other genomic regions previously associated with congenital heart defects. - Reveal a strong association between cardiac ultrasound findings and chromosomal abnormalities, both microscopic and cryptic. In pregnancies with cardiac findings, the observed frequency of microscopic chromosomal abnormalities and chromosome 22q11.2 deletion syndrome has been 15.9% (44/276) and 6.4% (5/78), respectively. Moreover, CMA has been performed in 51 fetuses with cardiac ultrasound findings, normal karyotype and negative or no FISH study for chromosome 22q11.2 deletion syndrome, and the detection rate of pathogenic copy number variants has been 2%, without detection of variants of unknown clinical significance. If in the initial series of 276 pregnancies the strategy QF-PCR + CMA would have been applied; all the chromosomal abnormalities with clear clinical repercussion diagnosed by conventional cytogenetics would have been identified, together with the deletions of 22q11.2 region and an extra 2% of chromosomal abnormalities. These results show the potential of CMA for the prenatal diagnosis of these pregnancies. - Show the usefulness of the molecular cytogenetic techniques FISH, MLPA and CMA when used as a complement to conventional karyotyping in cases with chromosomal abnormalities not accurately characterizable by conventional cytogenetics. Accordingly, the results obtained suggest the need for updating current prenatal cytogenetic diagnostic protocols.
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Maroto, González Anna. "Nivell neurològic prenatal en fetus afectes de mielomeningocele sotmesos a cirurgia intraúter". Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/454873.
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El mielomeningocele (MMC) és una malformació congènita caracteritzada per l'extrusió de la medul·la com a conseqüència d'una falta de fusió d'arcs vertebrals que dóna lloc a una lesió neurològica. El pronòstic motor dels nadons afectes de MMC s’estableix després del naixement amb la determinació del nivell neurològic mitjançant l’exploració dels moviments de les extremitats inferiors. Proposem que, d’una manera similar a l’exploració postnatal, l’avaluació ecogràfica sistemàtica dels moviments de les extremitats inferiors en fetus amb MMC podria ser realitzada per explorar el nivell neurològic prenatal i proporcionar informació sobre el pronòstic de la futura capacitat de deambulació, abans del naixement.
Objectius: Establir la correlació entre el nivell neurològic prenatal i el postnatal en casos sotmesos a la reparació intraúter del MMC, analitzar la reproductibilitat de la interpretació de la tècnica per l’avaluació ecogràfica del nivell neurològic prenatal, correlacionar el nivell neurològic prenatal amb el nivell anatòmic de la lesió, analitzar l’evolució del nivell neurològic en els casos que no es van operar prenatalment i descriure els casos de MMC valorats a l’Hospital Universitari Vall d’Hebron.
Mètodes: Estudi prospectiu observacional que inclou fetus afectes de MMC operats prenatalment. Els patrons de moviments de les extremitats inferiors dels fetus afectes van ser avaluats sistemàticament per ecografia per un expert en medicina materno-fetal i un especialista en rehabilitació. D'acord amb la funció nerviosa coneguda associada a cada grup muscular, es va establir el nivell neurològic prenatal. Totes les exploracions ecogràfiques van ser gravades i, posteriorment, van ser analitzades per dos observadors amb nivells d’expertesa diferents, els quals van interpretar cada exploració gravada per assignar el nivell neurològic, en dues ocasions diferents i cegats pels resultats de l’altre. La concordança entre el nivell neurològic assignat amb la tècnica d’ecografia prenatal i el nivell neurològic assignat després del naixement amb l’exploració neurològica clàssica va ser avaluada mitjançant l’índex de Kappa ponderat (wk). El mateix índex va ser utilitzat per establir la concordança entre el nivell neurològic i el nivell anatòmic i per analitzar la reproductibilitat intra- i interobservador.
Resultats: Es van valorar 93 fetus amb MMC. Després de l'assessorament, els pares decidien si desitjaven cirurgia prenatal (26 casos), interrupció de l’embaràs (48 casos) o cirurgia postnatal (2 casos). Cinc pacients no complien els criteris d'inclusió per a la cirurgia prenatal i tres van ser exclosos després del naixement. En els 18 fetus que es van sotmetre cirurgia i que es van analitzar, la concordança entre els nivells neurològics prenatals i postnatals assignats
va ser del 91,7% per a l'extremitat dreta (wκ = 0,80) i 88,9% per l'esquerra (wκ = 0,73). La concordança entre el nivell anatòmic i el nivell neurològic va ser del 62,0% (wκ = 0,024). Vint-i.vuit exploracions van ser registrades i avaluades per l’estudi de reproductibilitat. L'acord entre els observadors i l’expert en medicina materno-fetal es va mantenir constant per a l'observador amb major grau d’experiència (wκ = 0,82) i va augmentar (wκ = 0,66 - wκ = 0,72), per l'altre observador. La variabilitat inter- i intraobservador per l’observador més experimentat va ser wκ = 0,72 i wκ = 0,94, respectivament.
Conclusions: La correlació entre l’assignació prenatal i postnatal dels nivells neurològics obtinguda en aquest estudi mostra que l'avaluació del nivell neurològic és factible abans del naixement. La concordança per l’avaluació prenatal dels nivells neurològics va ser excel·lent per als observadors amb diferents graus d'experiència. Aquesta tècnica d'avaluació ecogràfica dels moviments de les extremitats inferiors té el potencial de proporcionar informació precisa i individualitzada sobre el pronòstic de deambulació en fetus amb MMC operats prenatalment.Myelomeningocele (MMC) is a congenital malformation characterized by the extrusion of the spinal cord as a result of a lack of fusion of vertebral arches leading to a neurological lesion. Motor prognosis of neonates affected by MMC is usually established after birth by the examination of lower limb movements to determine the neurological level of lesion. We propose that, in a similar manner, a systematic ultrasound evaluation of lower-limb movements in fetuses with MMC should be performed to explore the prenatal neurological level of lesion and provide the prognosis for future ambulation before birth. Objectives: To establish the correlation between the prenatal and postnatal neurological level in fetuses with MMC repaired in utero, to assess the reliability of the interpretation of the technique for the ultrasound evaluation of the prenatal neurological level, to correlate the prenatal neurological level with the anatomical level of lesion, to assess the evolution of the neurological level in cases not operated prenatally and to describe the MMC cases evaluated in Hospital Universitari Vall d’Hebron. Methods: prospective observational study including fetuses with MMC operated on prenatally. The patterns of movements in the affected fetuses’ lower limbs were evaluated systematically by ultrasound examination by a maternal-fetal medicine expert and a specialist in rehabilitation. According to the known nerve function associated with each muscle group, the segmental level of neurological lesion was established before birth. All ultrasound scans were recorded and, afterwards, were analyzed by two observers, with different levels of experience, who interpreted each recorded scan to assign the neurological level, two different times and blinded to each other’s results. The agreement for the neurological levels assigned, between the prenatal ultrasound technique and the classical neurological clinical examination after birth, was tested using the weighed kappa (wκ) index. The same index was used to establish the agreement between neurological level and anatomical level and to test the inter-observer and intra-observer reproducibility. Results: Ninety-three fetuses with MMC were evaluated. After counseling, the parents opted for prenatal surgery (26 cases), termination of pregnancy (48 cases) or postnatal repair (2 cases). Five patients did not fulfil the inclusion criteria for prenatal surgery and three were excluded after birth. In the 18 fetuses that underwent surgery and were analyzed, the agreement between prenatal and postnatal neurological levels assigned was 91.7% for the right limb (wκ=0.80) and 88.9% for the left limb (wκ = 0.73). The agreement between neurological level and anatomical level was 62.0% (wκ=0.024). Twenty-eight scans were recorded and evaluated to assess the reproducibility. The agreement between the observers and the expert in maternal-fetal medicine remained constant for the observer with greater experience (wκ=0.82) and increased (wκ=0.66 - wκ=0.72) for the other one. Inter-observer and intra-observer variability for the most experienced observer were wκ=0.72 and wκ=0.94, respectively. Conclusions: The agreement found between prenatal and postnatal assignment of neurological level of lesion in this study shows that the evaluation of neurological level is feasible before birth. The agreement for the prenatal evaluation of the neurological level was excellent for observers with different degrees of expertise. This technique of ultrasound evaluation of lower-limb movements has the potential to provide accurate individualized information about the ambulation prognosis of fetuses with MMC operated on prenatally.