Dissertations / Theses on the topic 'Testis, embryology'
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Quinn, Feargal M. J. "Unilateral cryptorchidism : an evaluation of the undescended and scrotal testes in an animal model." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295360.
Full textCravo, Roberta Mascioli. "Controle da expressão do gene ALDH1A2 (RALDH2) durante o desenvolvimento: uma abordagem filogenética." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-11112008-154726/.
Full textRetinoic acid (RA) is essential for embryogenesis. The key RA synthetic enzyme during early development is ALDH1A2 (RALDH2), a retinaldehyde dehydrogenase that converts retinaldehyde into RA. To understand how aldh1a2 is regulated we screened the gene for evolutionary conserved regions (ECRs) among vertebrates and assayed their regulatory potential. We describe an aldh1a2 intron 1 ECR (identified as RALDH2.2) that is conserved in amphibians, avians and humans and acts as an enhancer in derivatives of ectoderm, endoderm and mesoderm. Transient and stable transgenesis in mice reveal strong activity of the raldh2 intron 1 enhancer at the roof plate of the neural tube and at the growing epicardium. Transgenic mice indicate that the enhancer is activated in proepicardium-derived cells by contact and/or close proximity to the myocardium. The identification of an aldh1a2 conserved enhancer supports the idea of a modular regulation and shows that the evolutionary approach is an efficient tool to identify control mechanisms of the aldh1a2 gene.
Naudin, Stéphane. "Le développement embryo-larvaire du danio zébré (Brachydanio rerio) : évaluation de ce modèle pour la mesure de la toxicité des effluents et des sédiments : apports de l'analyse d'images pour les mesures biométriques de l'essai embryo-larvaire." Metz, 1996. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1996/Naudin.Stephane.SMZ9609.pdf.
Full textEffluent and sediment toxicity can be measured by a great number of bioassays in laboratory conditions. The reliability of the embryo-larval stage test using zebra danio (brachydanio rerio) was evaluated for effluent and sediment samples using several methodological improvements. We determined the tolerance range of this organism to different physico-chemical parameters (pH, dissolved oxygen, hardness, un-ionized ammonia) in order to evaluate their contribution to the toxicity noticed during the tests. The advantages of using an image analysis technique in order to count and measure larvae and detect gross morphological deformities were also assessed. After testing different industrial and municipal wastewaters, the minimum toxic concentrations detected by the embryo-larval test on zebra danio were greater but in the same order of magnitude as the ones obtained by two chronic bioassays on Selenastrum capricornutum and/or ceriodaphnia dubia. The sensitivity of the "fish" model to un-ionized ammonia and a teratogenic compound (dibutylphthalate) often found in municipal wastewaters justifies its integration into a battery of bioassays. Furthermore, we found the control values of the toxic end-points to be homogeneous among the embryo-larval stage tests. On the other hand, this test showed a lower relevance to measure sediment toxicity in comparison to the Microtox test (photobacterium phosphoreum) applied on whole sediment
Melo, Luana Felix de. "Desenvolvimento embríonário do fígado do Tubarão-azul, Prionace glauca (Linnaeus, 1758), Elasmobranchii, Carcharhiniformes." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-15062018-155713/.
Full textThe blue shark (Prionace glauca), popularly known as blue dogfish among all shark species is the most abundant in the marine environment, and can be found in all seas. With the diversity of species, the description of any specific liver can hardly be used as a model. Together with this variability, some physiological characteristics of the fish contribute to increase its hepatic polymorphism, however, it can be considered the starting point for comparative and phylogenetic studies among vertebrates. Fish liver appears as in all other vertebrates as a key organ that will control many vital functions and play a prominent role in fish physiology, both in anabolism (proteins, lipids and carbohydrates) and in catabolism (nitrogen, glycogenolysis and detoxification). On the other hand, it should be considered as a target organ for many biological and environmental parameters that can alter the structure and metabolism of the liver, such as food, toxins, parasites, microorganisms and accumulated heavy metals. In fish, the liver is located ventrally in the coelomic cavity, adjusting to the available space in the body cavity. The structural morphology of blue shark liver development in 33 specimens divided into different sizes of embryos and fetuses from 4 cm to 45 cm was compared to a female adult of 2 meters, using light microscopy and scanning electron microscopy. The counts of hepatocytes and fat vacuoles were by morphometry, using the technique of points in random photomicrographs. In the results obtained, it can be noted that the liver occupied 20% of the size of the animal. Microscopically, it observed the presence of different sizes of lipid storage vacuoles in hepatocytes, a difference in the proportions of hepatocytes, lymphocytes and blood vessels that decreases as lipid storage increases, consequently decreasing the visibility of the liver structure. Greater visualization of microcyticular intracytoplasmic translucent vacuoles gradually increasing for macrogoticulares. Thus suggesting that the presence of lipids is for the maintenance of the puppies, buoyancy and energy reserve of the animal, indicating that it stores fat in its liver from the beginning of embryogenesis.
Souza, Aline Fernanda de. "Estudo biológico das células germinativas caninas." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-14112013-150423/.
Full textEmbryonic germ cells are pluripotent cells derived from primordial germ cells which arise during embryonic development. These cells are precursors in the maturation of gametes and for proliferation and formation of new generations of germ cells. Studies using animal models for pluripotent embryonic stem cells have been conducted successfully in the treatment of many genetic diseases, especially using canine models, due the homology between canine and humans. Therefore, we aimed to establish a study of canine biology of germ cells for future research, aiming viability therapy. For this study, we used female mongrel dogs (SRD), which underwent ovary- salpingo- hysterectomy, arising from castration campaigns run by associations and/or NGOs in Pirassununga city. The embryos collected were analyzed using histology methods following the timeline and measure by measuring Crown-Rump (CR) then in an environment without contaminants (sterile) the embryos were micro-dissected focusing in the paramesonephric region near the region of somite where the germ cells are. The fragments were isolated and placed in culture with a specific media for the development and spread of primordial germ cells (PGCs). Success was achieved in cultures with embryos at a gestational age close to 22 to 30th days of gestation, in which the cells showed a rounded morphology and small. In electron microscopy and transmission analyses, sizes were observed between the cells attached to each other, showing a conspicuous nucleus and in the cytoplasm was observed several types of cell organelles, especially mitochondria. Immunohistochemical analysis revealed the positive immunolabeling for Oct4, suggesting the presence of pluripotent cells and germ cells. The analyses using immunophenotyping by flow cytometry showed low expression for Oct4 while for CD34 and C-kit markers had positive expression. RT-PCR showed expression of the pluripotency markers Oct4 and Sox2. By the technique of Western Blotting identified protein expression specific for Oct4. Thus these findings suggest the successful establishment of culture, proliferation and development of primordial germ cells canine.
Vellutini, Bruno Cossermelli. "Desenvolvimento e ciclo reprodutivo da bolacha-do-mar Clypeaster subdepressus (Echinodermata: Echinoidea) de São Sebastião, SP." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/41/41133/tde-17022009-105310/.
Full textEmbryonic, larval, and juvenile development of the sea biscuit Clypeaster subdepressus is described with light and scanning electron microscopy. The reproductive cycle of the species is analyzed based on histological sections of the gonads. The morphological evolution of the order Clypeasteroida (sand dollars and sea biscuits), about 55 million years ago, was associated with the occupation of sand beds. Data on morphology of living and fossil echinoids suggests that during the evolution of sea biscuits juvenile characters were retained into adulthood. We obtained ripe gametes by KCl injection into the perivisceral coelomic cavity of adults and fertilized the eggs in vitro. We kept embryos and larvae in cultures at 26 °C and fed larvae with microalgae. Eggs (mean diameter of 160 m) are spherical, translucent, and white. After sperm entry, the vitelline envelope hardens between 2 and 6 min; male pro-nucleus begins to migrate towards the center of the egg 5 min later, taking 12 min at 0.1 m/s to fuse with the female pronucleus. Cleavages are holoblastic with the formation of macromeres, mesomeres, and micromeres. Blastulae are formed between 3.5 and 6.5 h after fertilization (hpf), develop cilia, and hatch 7.5 hpf. Gastrulation begins on the vegetal plate with the unipolar ingression of primary mesenchyme cells 10 hpf. Archenteron extension, ingression of secondary mesenchyme cells, and the formation of larval skeleton occurs until 30 hpf. In less than 48 hpf the celomic pouches are formed and on day 3 larvae begin to feed. Hidropore opens on the abanal surface of larvae while vestibule invagination takes place between the post-oral and postero-dorsal arms on the left side 5 dpf. Vestibule fuses with the left celom forming a rudiment which develops spines and podia still inside the larvae. Larvae become competent _20 d after fertilization and only metamorphose in the morning, after contact with sand from adult populations or food. After complete eversion of the rudiment, the larval epidermis retraction takes 1 h 30 min. Post-metamorphic juveniles do not have anus or mouth; they have 15 spines and 15 podia (of 2 types); 5 sphaeridia on the oral surface; aboral surface does not have plates, except for the remnants of larval spicules. Rudiments of the Aristotles lantern are organized in 5 groups. Each group has 1 tooth, 2 hemipiramids, and 2 epiphysis; a rudiment rotula is placed between the groups. Hemipiramids are formed 2 d after metamorphosis (dpm); teeth become more robust and hemipiramids fuse into piramids 7 dpm. The digestive tract appears and the anus opens on the aboral surface 2 dpm. The peristomial membrane is functional and the mouth opens 7 dpm. Ophicephalous and tridentate pedicellariae appear on the posterior region 14 dpm and 30 dpm, respectively. Growth of juveniles reared in the laboratory was slow: post-metamorphic juveniles were _250 m in diameter and reached _500 m 8 months later. We described 6 stages of gonadal growth in males and females of C. subdepressus. We found premature stages and ripe gametes more frequently between December and March (summer), while recovery stages were dominant from May until September (winter). Females have a longer period of growing stage than males. The area occupied by the germinal epithelium on a transverse section of a gonadal lobe is lower in mature stage. Gonads are heavier during the premature stage. Data suggest that C. subdepressus from São Sebastião has an annual reproductive cycle where gonadal recovery occurs during winter, nutrient storage by October, and spawning between February and March.
Constantino, Maria Vitória Piemonte. "Morfologia e organogênese em dois períodos gestacionais em suínos (Sus scrofa domesticus)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-01072013-090720/.
Full textThe study aimed to characterize the morphological and organology development of Landrace pigs embryos (Sus scrofa domesticus) at 20 days (n=6) and 30 days (n=6) post artificial insemination (p.i.) through macroscopic and microscopic techniques, besides morphometric analysis of the major organs (heart, lung, liver and mesonephros) inferring its importance in the conseptus maintenance. Embryos at 20 days p.i. macroscopically presented translucent skin; forebrain, midbrain and hindbrain; optic vesicle without retinal pigmentation; branquial arches; cervical curvature; forelimb budshaped \"paddle\"; liver; heart; mesonephros; somites and dermal vasculature. In the histological analysis were visualized the encephalic vesicles (forebrain, midbrain and hindbrain); branquial arches with its respective pouches and clefts; encephalic flexure; in the thoracic and abdominal portion the heart and liver respectively; mesonephros (primitive kidney); primitive gut and somites. Morphometrically, the major organs (heart, liver and mesonephros) of embryos at 20 days p.i. did not differ significantly (p<0.05) demonstrating organologycal appropriate development at this stage. The morphological and histological evaluations of embryos at 30 days p.i. revealed similar characteristics to the embryos at 20 days p.i., except for the presence of the 4th encephalic ventricle; accentuated cervical curvature; nasal pit; optic vesicles with pigmentation of the retina; thoracic and pelvic members with distinction of the digits; tail, voluminous liver, and vertebral column, macroscopically; and the presence of secondary encephalic vesicles; spinal cord; medulla oblongata; 3rd encephalic ventricle; vertebral column; lung; \"U-shaped\" intestine, and mesonephros, microscopically. However, statistical analyzes revealed that the morphometric evaluations the heart, lung, liver and mesonephros differ significantly (p<0,05) regarding the development of the major organs. The comparison between the means of the total areas of the heart, liver and mesonephros, through Man-Whitney test indicated that the embryos at 20 and 30 days p.i., demonstrated significant differences (p<0,05). This study suggested that the embryo uniformity and development rate may be crucial in the maintenance of the conceptus during the gestational period. However, more studies are necessary to elucidate the mechanisms of the embryonic development regarding the first third of pregnancy in order to minimize gestational losses in swine.
Palazzi, Eduardo Gimenes. "Efetividade da tripsina sobre embriões murinos infectados experimentalmente com BoHV-1." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/87/87131/tde-03012011-090553/.
Full textThis study evaluated the effectiveness of treatment with trypsin (TT) in the elimination of BoHV-1 Colorado, which causes infectious bovine rhinotracheitis (IBR) Swiss female mice, aged 6 and 8 weeks, were superovulated with 0.2 mL 5UI hormone eCG and 48h after hCG and mated with males of the same lineage and age. After 18 hours, females were euthanized, and through na opening in the peritoneum, the zygotes were collected. Zygotes were separated for five trials that provided the following data: the Colorado BoHV-1 alters the cleavage rate and embryo morphology; trypsin, following recommendations of the IETS, does not damage the embryo; the embryos exposed to the virus and subjected to TT does not change their morphology and cleavage rate; were detected (nested-PCR +) viable virus (MDBK +) after the TT. These results demonstrate that TT was not effective to eliminate the BoHV-1 Colorado, but in some tests showed the TT efficiency in inactivating the virus makes it na important method of control in vitro.
Costa, Marcos Sawada Simões. "A sinalização pelo ácido retinóico e a origem evolutiva das câmaras cardíacas." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-09062009-110021/.
Full textIn the last years, we have proposed a 2-step model for the establishment of cardiac chamber identities. Retinoic acid (RA) produced by its synthetic enzyme RALDH2, induces an atrial fate in posterior cardiac precursors of amniote embryos. Subsequently, a RALDH2 caudorostral wave engulfs posterior precursors. Our hypothesis is that this wave evolved in vertebrates to pattern an ancestral circulatory pump into AP fields, which were later fashioned into cardiac chambers. To test whether the wave is an ancestral or derived feature of amniotes, we mapped expression of RALDH2 in relation to the cardiac field in amphibians, basal vertebrates and the amphioxus. Our data suggests RA signaling patterns amphibian and piscine hearts. Cloning of RALDH in lampreys shows that RA synthesis takes place in the heart field. In the amphioxus, cloning of RALDH reveals a vertebrate-like expression pattern, although the RALDH2 wave is absent. Our results support the hypothesis that the caudorostral wave of RALDH2 was coopted to pattern the vertebrate cardiac field. This supports the hypothesis that the caudorostral wave of RALDH2 was an important player in the evolutionary origin of the cardiac chambers.
Alvarez, Camila Wenceslau. "Fissura pré-forame incisivo uni/bilateral e fissura pós-forame incisivo associadas: estudo genético-clínico." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/61/61132/tde-27012011-100819/.
Full textPurpose: To contribute to the expansion of knowledge about oral clefts, describing the clinical and genetic aspect of a sample of individuals with cleft lip associated with cleft palate, without alveolar arch involvement, showing or not other abnormalities. Patients and methods: We selected 356 patients with incomplete cleft lip uni/bilateral associated with cleft palate, without alveolar arch involvement, registered and in treatment at the Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de São Paulo, Bauru, SP. Data for sexual ratio, parental age at the time of conception, parental consanguinity, familial recurrence, laterality of cleft and presence of associated anomalies were investigated. Regarding the analysis of the results two groups were detached (Group I and Group II) from the total sample. In Group I it was included individuals who had healed cleft lip, regardless of the type of palate involvement. Individuals in Group I, which, besides having had healed cleft lip also had some type of microform cleft palate were also detached to form Group II. Statistical tests were performed for comparison between groups and remainder of the sample, and between the total sample and literature data. Results and Discussion: There was a statistically significant difference between the total sample and literature data regarding laterality of the cleft, sexual ratio, consanguinity, familial recurrence and presence of associated anomalies. There was also a statistically significant difference between Group II and the remainder of the sample regarding paternal age, and between Groups I and II and the total sample in relation to the occurrence of multiple anomalies associated with cleft. The sample has, in general, the same genetic and clinical characteristics of the group of cleft lip with or without cleft palate (CL/P). The differences did not allow distinction between cleft lip associated cleft palate without involvement of the alveolar arch (CL+CP) and CL/P. Likewise it is not possible to affirm, from the results obtained, that Groups I and II are distinct from the total sample. Conclusion: Although we can not say that CL+CP is distinct from the CL/P, its peculiar features indicate to this differentiation. Individuals with microforms of cleft constitute a target group for research on possible genetic mechanisms that lead to varying severity of these malformations.
Sampaio, Allysson Coelho. "Regulação molecular da expressão atrial - específica do gene SMyHC3." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-05082010-113049/.
Full textTo elucidate the genetic pathways controlling cardiac chamber formation, the atrial specific gene promoter SMyHC3 was analyzed. In transgenic mice, the atrial specific expression an 840 bp of the SMyHC3 promoter was linked to reporter gene human alkaline phosphatase (HAP), SMyHC3-HAP. By directed mutagenesis and deletion analysis we identified the more distal 72 bp of the promoter as responsible of the atrial expression. This fragment contains putative binding sites to nuclear receptors, the CNRRE (complex nuclear receptor response element), defined by molecular modeling. RA (retinoic acid) treatment in SMyHC3-HAP embryos expands the atrial domain. However, the RA effectors, RXR/RAR bind with low affinity to the SMyHC3 promoter. These receptors are not able to activate the promoter even in the presence of coactivators such as p300, CBP and GRIP1. These results suggest that RA acts indirectly to regulate this atrial marker. Cell transient transfection shows that COUPTF2 activate the SMyHC3 promoter, and COUPTF2 siRNA inhibits the transactivation of the SMyHC3 promoter. Treatment of embryos with RA increases the COUPTF2 expression reinforcing the idea that this receptor could be regulatedindirectly by RA. Bioinformatic studies revealed that CNRRE is present in the 3 region of the ortholog chicken AMHC1 gene. Alignments indicate that this CNRRE could have been acquired by an exaptation event. In conclusion, the SMyHC3 promoter seems to be controlled by RA and COUPTF2 governing atrial expression. However the nature of relationships between RA and COUPTF2 need to be elucidated.
Vieceli, Felipe Monteleone. "Clonagem e análise da expressão do fator de transcrição Scratch2 durante a embriogênese inicial de galinha." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-02022010-112918/.
Full textIn invertebrates, the Scratch (Scrt) genes encode transcription factors that promote neurogenesis during development. The Scrt function in vertebrates is unknown, but in mice Scrt1 and Scrt2 are specifically expressed in post-mitotic neurons in the embryo and in the adult central nervous system. In this work, we have cloned the coding sequence of chicken Scrt2 (cScrt2) and characterized its expression pattern in the embryo with quantitative PCR and in situ hybridization. The complete coding sequence was cloned in the expression vector pMES-GFP and the predicted translation product is a 276-aminoacids protein. The aminoacid sequence shares identities of 70% with rat Scrt2 and 58% with zebrafish Scrt. cScrt2 transcripts are firstly detected in the periphery of the neural tube in the hindbrain by HH 15 and in the spinal cord by HH 17, coinciding with the places where some of the first neurons differentiate during embryogenesis. Between HH 19-23, the expression in the motor domain of the spinal cord is progressively concentrated in the interface between the ventricular and mantle zones. Furthermore, cScrt2 expression is also observed in the dorsal root ganglia after HH22-23, particularly in the dorsomedial domain. The expression pattern of cScrt2 in the neural tube is complementary to that of Notch1, which is expressed in neural stem cells, and SCG10, a marker for differentiated neurons. Our results suggest that during embryogenesis cScrt2 is specifically expressed in post-mitotic undifferentiated neurons. The construction pMES-GFP(cScrt2) makes possible future direct functional analysis by genetic interference in the chick embryo, which will be of great value for better understanding the Scrt genes function in vertebrates.
Oliveira, Bruno de. "Estudo do potencial vascular de precursores de vasos coronários em sítio adulto." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-22072011-150121/.
Full textThe Proepicárdio (PE) is a transient structure giving rise to all components of the coronary vessels. To evaluate the vasculogenic potential of the PE in an adult site, a neonatal heart was transplanted into the subcutaneous of an adult ear Later, two PE from GFP-transgenic mice were transferred to the surface of this heart. In another group, we transferred the PEs directly into the ear pinna. To evaluate the incorporation of GFP cells derived from the PE, and to investigate their possible differentiation, we performed immunofluorescence (IF) for GFP in combination with other markers. The addition of PE in an adult site resulted in its participation in a vasculogenic and in an angiogenic processes. Based on this we conclude that PE cells can differentiate and likely participate in a neovascularization process when transplanted to adult sites. These findings demonstrate that the vasculogenic potential of the PE cells is conserved in an adult site and our model is adequate to study the mechanisms involved in the development and regeneration of vasculature.
Azambujá, Ana Paula. "Mecanismos embrionários de diferenciação de precursores coronários: princípios para aplicação em terapia celular." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-09112009-144701/.
Full textCoronary vessels derive from the proepicardium (PE), a structure formed by precursor of coronary vessels cells, endothelial and smooth muscle cells (CoSMC). In vivo there is a clear gap between the endothelial differentiation and the integration of CoSMC into the vascular tubes. The aim of this work was to understand the mechanisms controlling the delayed in vivo CoSMC differentiation. Based on the progressive loss of expression of raldh2, the main retinoic acid (RA) synthesizing enzyme, we explored the RA signaling as a possible candidate inhibitor of CoSMC differentiation. Using a adenoviral raldh2 expression system and in vivo inhibition of RA synthesis we showed that RA signaling act as a brake to slow CoSMC differentiation in PE-derived cells. We also identified VEGF as key factor acting on the control of CoSMC differentiation. Together our results support a model that AR and VEGF synthesis during cardiac development was co-opted to block the CoSMC differentiation of coronary precursors before an extensive endothelial network of tubes is established.
Junior, Antonio Euclides Pereira de Souza. ""Acetato de medroxiprogesterona administrado em período pré-natal induz hipospádia em machos e virilização em fêmeas de camundongos"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/5/5153/tde-17022006-105731/.
Full textIn vitro fertilization (IVF) has been associated with an increase incidence of hypospadias. IVF protocols require the maternal use of progesterone which may be a factor in causing hypospadias. To test these hypotheses in an animal model, we describe the effects of maternal progesterone exposure on genital development in mice. Medroxyprogesterone acetate (MPA) was administered by subcutaneous injection during the pre-natal period to wild type mice and animals knockout to androgen receptors (Tfm mice). Progesterone caused hypospadias in male mice fetuses, a virilizing effect in the female mice genitalia and didn't have any effect in Tfm animals
Silva, Rimena de Melo Germano da. "Comparação do comprimento do úmero em fetos portadores de Síndrome de Down com o comprimento do úmero em fetos normais." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5139/tde-20052014-105722/.
Full textObjective: This study aimed to compare the humeral length (HL) in fetuses with Down syndrome (T21) with HL in normal fetuses, by using instruments of reference of the local population. Method: A case-control study was conducted comparing HL in normal fetuses with HL in fetuses with T21, aged between 18 weeks and 23 weeks and 6 days. Fetuses with T21 who were examined between 1994 and 2012 were included. The normal controls were evaluated between 2007 and 2009. The averages, medians, and standard deviations were obtained for maternal age, gestational age, and HL. Afterwards, we analyzed the correlation between the HL and the gestational age, with values expressed as multiples of the median (MoMs). The HLs of fetuses with T21 were compared with the HLs in normal fetuses by using Student\'s t-test. The humeri were evaluated considering the cut-off levels below the 10th, 5th, and 2,5th percentiles to obtain the sensitivity. The likelihood ratios (LR) were also calculated. Next, a general linear model was used with maternal age as a covariate to control for comparison of the groups. Comparison was also made between the HL of fetuses in the local population and the expected HL, based on the Jeanty curve. The tests were performed with a significance level of 5%. Results: The study included 58 cases with T21 and 1888 normal controls. The sensitivity of the HL to detect T21 by using a cut-off level below the 10th percentile was 44.8% with a LR of 4.4; below the 5th percentile, the sensitivity was 34.4% with a LR of 6.9; and below the 2.5th percentile, the sensitivity was 31.0% with a LR of 12. The average value of the humerus, in MoMs, of fetuses with T21 is statistically lower than that of normal fetuses (p < 0.001), as measured by using Student\'s t-test. When maternal age was controlled as a covariant in the comparison between groups, the difference remained statistically significant (p < 0.001). An analysis to compare the HL in normal fetuses of the local population with expected HL based on the Jeanty curve concluded that the HL in normal fetuses of the local population is lower than expected. Conclusions: There is a statistically significant difference between the HL of normal fetuses and HL of fetuses with T21 in the local population (p < 0.001). The sensitivity for detection of T21 was 44.8%, 34.4%, and 31% for the humerus below the 10th, 5th and 2.5th percentile, respectively. The Jeanty curve is not adequate to use as growth control for humeri in local normal fetuses, as its use leads to an increase in false positive rates when measuring the proportion of short humeri
Júnior, Sérgio Nakazone. ""Avaliação comparativa da anatomia do desenvolvimento da articulação temporomandibular, por meio do uso de ressonância magnética, reconstrução digital e cortes histológicos"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/23/23137/tde-06062005-154043/.
Full textThe present study was carried out to evaluate the effectiveness of Magnetic Resonance Imaging (MRI) and bi and three-dimensional digital reconstructions of the TMJ in different stages of development, by the comparison with histological sections. A proper protocol of IRM examination was developed, which was applied in formalin-preserved human embryos and fetuses, ranging from 22 to 160mm of crown-rump length (CRL), between 7 and 18 weeks of intrauterine life (IU). Two sequences of sagital images of the entire head of each specimen were performed, with interslice gap of 1,0mm. Consequently, images were digitally intercalated, creating a slice sequence of 0,5mm of interslice gap. These images were imported to the MRIcro Ò program for bi and three-dimensional digital reconstruction. In order to evaluate the development of the articular structures of each one of the specimens, histological sections of the TMJ were obtained. The maturations degree and the quality of the collagen matrix of the TMJ were determined by the histological sections . The results showed that the developed protocol was capable of capture and process MR images, mainly in the articular maturation stage, after the 13 th week of IU. Histological findings also showed that articular structures are better identified in this stage by RMI examination. This can be explained due to an increase of cellular and collagen matrix differentiation, which undergoes conversion from collagen type III to type I. Bi and three-dimensional models seem to be an efficient tool for the diagnosis of facial development, facilitating its understanding and learning. Further studies and technological advances may be necessary for its application in TMJs structures in intrauterine period.
Otto, Aline Pedrosa. "Análise molecular do gene HES1 em pacientes portadores de hipopituitarismo congênito." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5135/tde-27082014-112356/.
Full textStudies of transgenic animal models have allowed for the discovery of genes involved in human pituitary embryogenesis and the genetic etiology of hypopituitarism. However, the genetic causes of most cases of congenital hypopituitarism, especially those associated with an ectopic posterior pituitary, remain poorly defined. Mutations in the gene PROP1 are the most common genetic causes of hypopituitarism described to date, and are always associated with an ectopic posterior pituitary. Studies to elucidate the molecular mechanisms of Prop1 mutations in mice have demonstrated the involvement of the Notch signaling pathway, including its downstream target Hes1. The HES1 gene encodes a transcription factor that participates in early stages of pituitary development and is involved in posterior pituitary morphogenesis. Hes1 knockout mice exhibit a hypoplastic anterior pituitary and absence of a posterior pituitary. Conversely, constitutive expression of Hes1 is associated with hypopituitarism. Since an ectopic posterior pituitary is commonly found in congenital hypopituitarism and the HES1 gene may be related to its pathophysiology, the coding region of gene HES1 was screened in 192 patients with congenital hypopituitarism. A heterozygous allelic variant c.578G >A (p.G193D) was identified in a patient with congenital hypopituitarism associated with an ectopic posterior pituitary. Assessment by MutationTaster, a bioinformatic tool for in silico prediction of functional effect of missense variants, suggests that substitution of glycine (a highly conserved amino acid in this position among mammals) for aspartic acid is deleterious. In the genetic study of family members, we identified four apparently normal siblings with the same variant, two of which have discrete changes in their pituitary MRI. In conclusion, we described a new allelic variant in the gene HES1, absent in large databases and healthy Brazilian controls, but present in the unaffected siblings. In vitro functional studies are needed to clarify the biological effect of this variant. A complex pattern of inheritance with incomplete penetrance is possible in this case, as it has already been described in other genes associated with hypopituitarism. In an attempt to elucidate the genetic cause of hypopituitarism in the family described, DNA samples of this patient and his family were submitted to exome sequencing, but results are inconclusive at this time
Santos, Guilherme Francisco. "A teoria da gastrea de Ernst Haeckel." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/8/8133/tde-26062012-141751/.
Full textThe main goal of our work is to describe and critically analyze the core of the gastrea theory of Ernst Haeckel. It centers around two main notions: gastrula form and metazoan. The gastrea theory is a set of formulations designed to establish a definition of metazoan from the notion of gastrula form. The central argument of the gastrea theory articulates these two notions to organize from studies of comparative embryology an overview of evolutionary history of the animal kingdom.
França, Marcela Moura. "Análise dos genes GHRH e GL12 em pacientes com deficiência de hormônio do crescimento congênita." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/5/5135/tde-25042012-142522/.
Full textIntroduction: Alterations in genes related to GH secretion and pituitary organogenesis have been identified in patients with congenital GH deficiency (GHD). However, in only few cases of GHD the etiology has been established. GH-releasing hormone (GHRH) is an obvious candidate to explain isolated GH deficiency (IGHD). Previous reports in the literature did not identify mutations in GHRH, however, the methodology used was limited. Most patients with combined pituitary hormone deficiency (CPHD) have an ectopic posterior pituitary lobe (EPP) suggesting the study of genes involved in early pituitary development and also expressed in the infundibulum. GLI2 is a transcription factor in Sonic hedgehog signaling expressed in the primordial Rathkes pouch and ventral diencephalon during early pituitary development. Previously, GLI2 mutations were found in patients with holoprosencephaly and pituitary abnormalities. Aim: Analyse GHRH in 151 patients with IGHD (42 Brazilian and 101 from international centers) and GLI2 in 180 Brazilian patients with IGHD or CPHD by PCR and automatic sequencing, and describe the phenotype of patients with mutations. Results: In GHRH, six heterozygous variants that are benign according to in silico analysis were identified. GLI2 study revealed three novel heterozygous mutations leading to premature stop codons (p.L788fsX794, p.L694fsX722 e p.E380X) and truncated proteins, without the transcriptional activator domain. p.L788fsX794 was identified in a girl with short stature, polydactyly, epilepsy and hypoglycemia. She had GH, TSH, ACTH, prolactina, LH and FSH deficiencies. Two uncles had IGHD and one cousin CPHD. These relatives, the mother and other maternal relatives had polydactyly and carried the mutation. p.L694fsX722 was identified in a boy with short stature due to GHD who also had cleft lip and palate. His healthy father also carried the mutation. p.E380X was identified in an infant with delayed development, hypoglycemia, polyuria and polydipsia. She had GH, ACTH, TSH and ADH deficiencies. Her apparently normal mother also carried the mutation. All patients with GHD and GLI2 mutations had an EPP (not visualized in the patient with p.E380X), hypoplastic anterior pituitary lobe and absence of holoprosencephaly on MRI. Eighteen non-synonymous variants in GLI2 were identified in 24 patients. Sixteen of these were considered deleterious in at least one in silico prediction program and ten of these were not found in the control population. The phenotype was mainly of CPHD and EPP without holoprosencephaly. Several synonymous and intronic GLI2 variants and polymorphisms apparently without functional consequences were identified. Conclusions: No mutations in GHRH were identified and if mutations in this gene exist as a cause of IGHD, they must be very rare. Variants in GLI2 are frequent (15%) indicating its important role in the etiology of GHD. Furthermore, we expanded the clinical spectrum of patients with GLI2 mutations characterized by IGHD or CPHD including diabetes insipidus, ectopic posterior pituitary lobe (in most patients) and absence of holoprosencephaly. Additional features were polydactyly and midline facial defects and the inheritance was autosomal dominant with incomplete penetrance