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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Sox proteins and neurogenesis

Sandberg, Magnus, January 2010 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2010.
72

Pluripotent Stem Cells of Embryonic Origin Applications in Developmental Toxicology /

Jergil, Måns, January 2009 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2009.
73

O aconselhamento genético como prática clínica: a anencefalia em foco

Costa, Aline Teixeira da January 2010 (has links)
Made available in DSpace on 2014-08-06T17:29:38Z (GMT). No. of bitstreams: 2 Aline Costa.pdf: 2324687 bytes, checksum: 04115292021785e54c4bf64f9a7bc8fd (MD5) license.txt: 1914 bytes, checksum: 7d48279ffeed55da8dfe2f8e81f3b81f (MD5) Previous issue date: 2010 / Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Ensino. Programa de Pós-Graduação em Saúde da Criança e da Mulher. Rio de Janeiro, RJ, Brasil. / O objetivo desse trabalho foi discutir o aconselhamento genético (AG) como prática clínica, focalizando a anencefalia que é um defeito de fechamento de tubo neural (DFTN) aberto, acometendo 1:1000 nascimentos, e sua associação com outras malformações maiores. Para tanto foi empreendido o levantamento de laudos de necropsias realizadas no Departamento de Anatomia Patológica do Instituto Fernandes Figueira/FIOCRUZ, entre 2000 e 2008, e dos respectivos prontuários das gestantes dos quais constava o resultado dos achados da ultrasonografia gestacional (USG). A análise dos dados foi feita utilizando o Epi-Info/ANOVA. Os resultados apontaram: a) 74 necropsias realizadas no período, das quais 56,7% indicaram anencefalia isola, 14,9% mostraram outro DFTN e 28,4% associada com outras malformações; b) as malformações mais frequentemente associadas com a anencefalia foram: raquisquise, fenda labial ou e palatina, onfalocele, hérnia diafragmática e baço acessório; c) o diagnóstico da USG mostrou anencefalia isolada em 87,4% dos casos; associada com outro DFNT em 2,8% e múltiplas malformações em 9,8%, das quais as mais frequentes foram: raquisquise, onfalocele, defeito de parede tóraco-abdominal com ectopia cordis; d) a maioria das gestantes tinha segundo grau completo, eram primigestas, com história familiar de DFTN em 9,4% dos casos, sendo que em 6,7% deles houve exposição a teratogênos e 20% tiveram complicações gestacionais, sendo a polidraminia a mais frequente; e) em nenhum dos casos achou-se referência ao uso de ácido fólico pré e periconcepcional; f) após a confirmação diagnóstica, 49,3% gestantes decidiram pela interrupção judicial da gravidez e 50,7% evoluiram para o parto (36% natimortos e 64% nativivos) e, por fim, g) 42% das gestantes realizou consulta no ambulatório de AG pósnatal, depois do desfecho da gestação. Concluiu-se que diante do diagnóstico de anomalia tão grave e incompatível com a vida extra-uterina, as demais malformações perdem significado no momento da USG, o tem repercussões para o direcionamento do AG relacionado às opções reprodutivas futuras. Por outro lado reiterou-se a importância da suplementação oral de ácido fólico no período pré e periconcepcional como medida de prevenção primária e de promoção da saúde. / The aim of this investigation was to discuss genetic counseling as a clinical practice, focusing on anencephaly, which is an open neural tube defect that affects 1:1000 births, and its relation to other major malformations. For this purpose, we undertook a survey of autopsy reports, performed at the pathology department of Instituto Fernandes Figueira/FIOCRUZ between 2000-2008, and medical charts of the related mothers, where data on the obstetric ultrasound was registered. Data analysis was performed with Epi-Info/ANOVA. The results point to: a) 74 autopsies were executed during this period; 56,7% revealed isolated anencephaly, 14,9% were associated to other neural tube defects, and 28,4% were associated to other malformations; b) malformations most frequently associated were: rachischisis, cleft lip and/or palate, omphalocele, diaphragmatic hernia, and accessory spleen; c) obstetric ultrasound showed isolated anencephaly in 87,4% of the cases; association to other neural tube defects in 2,8%, and multiple malformations in 9,8%, the most frequent being rachischisis, omphalocele, thoraco-abdominal wall defect, and ectopia cordis; d) the majority of pregnant woman had completed high school and were pregnant for the first time; family history for neural tube defect was positive in 9,4% of the cases, of which 6,7% were associated to teratogen exposure, and 20% presented with pregnancy complications, mostly polyhydramnios; e) we found no record of folic acid use before or peri-conception; f) after diagnosis, 49,3% of pregnant women decided for pregnancy interruption, and 50,3% delivered their babies (36% stillbirths, 64% newborns), and g) genetic counseling was given to 42% of women. We come to the conclusion that facing such a serious, and deadly anomaly, all other malformations loose their value, what reflects upon genetic counseling and reproductive choices. Besides, we emphasize the need of folic acid use before and peri-conception as a primary prevention and health promotion measure.
74

Perfil epidemiológico e nível sérico de ácido fólico em mães de crianças portadoras de defeito do tubo neural / EPIDEMIOLOGICAL PROFILE AND SERUM FOLATE IN MOTHERS OF CHILDREN WITH NEURAL TUBE DEFECT.

Pereira, Jesus Henrique Nicola 16 March 2011 (has links)
Neural tube defects (NTDs), which is a congenital malformation, in significant part on the statistics of perinatal morbidity and mortality due to their high incidence rates. The DA can be limited to the central nervous system and / or peripheral, and may also include the overlying tissues (bones, muscles and connective tissue). Folic acid (FA) is a nutrient that plays a fundamental role in the process of cell multiplication. And the remarkable importance of folic acid in preventing NTDs where published studies portray the relationship between the levels of PA and the birth of children with NTDs, whereby the higher the rate of serum folate, less frequent are the births of children with NTDs . Although he knows that the AF is directly linked to the prevention of NTDs, little has been epidemiologically demonstrated the use of it in our population (especially from the Northeast-SE Brazil). All study women received prenatal (PN), however from the second month of conception outside the period in which it is contemplated by the AF prevention, highlighting the lack of an effective family planning. Was not performed by folic acid supplementation in 56.6% of women studied and the other 43.3% who did, began after the second month of pregnancy, which had become ineffective in the prevention, the same vitamin, the DTN. Showed that only 3.3% of cases of NTD group had a gestational age was less than 37 weeks and 50% were primigravida, the same group. The women studied were aged 24.8 years on average to become pregnant. Epidemiological parameters when compared with the comparison group, were similar, since both groups used the same health service, with the characteristic of high risk. The levels of serum folate in a group of women studied, remained normal and the highest of scientific studies published so far with similar characteristics. Prevention with the use of folic acid should be intensified by the various sectors of society, the risk group studied, so to avoid the recurrence of neural tube defects, reducing the incidence and recurrence in women who are more likely to generate conceptuses with this malformation. / O defeito do tubo neural (DTN), que é uma malformação congênita, participa de modo considerável nas estatísticas de morbidade e mortalidade perinatais devido a suas elevadas taxas de incidência. Os DTN, podem se limitar ao sistema nervoso central e/ou periférico, e também podem incluir os tecidos sobrejacentes (ossos, músculos e tecido conjuntivo). O ácido fólico (AF) é um micronutriente que apresenta papel fundamental no processo de multiplicação celular. E notória a importância do ácido fólico na prevenção dos DTN onde, estudos publicados retratam a relação dos níveis de AF e o nascimento de crianças com DTN, segundo os quais, quanto maior a taxa de folato sérico, menos frequentes são os nascimentos de crianças com DTN. Embora que saiba-se que o AF está ligado diretamente à prevenção do DTN, pouco se tem evidenciado epidemiologicamente o uso do mesmo na população brasileira (em especial a da região Nordeste/SE/Brasil). Todas as mulheres estudadas realizaram pré-natal (PN), entretanto a partir do segundo mês de concepção, fora do período que contempla-se a prevenção pelo AF, evidenciando a falta de um planejamento familiar efetivo. Não foi realizada a suplementação por ácido fólico em 56,6% das mulheres estudadas e as outras 43,3% que a fizeram, iniciaram após o segundo mês de gestação, o que tornara ineficaz a prevenção, pela mesma vitamina, ao DTN. Evidenciou-se que apenas 3,3% dos casos do grupo DTN tiveram idade gestacional foi inferior a 37 semanas e 50% foram primigesta, do mesmo grupo. As mulheres estudadas tiveram idade média ao engravidar 24,8 anos. Os parâmetros epidemiológicos, quando comparados com o grupo de comparação, mostraram-se semelhantes, uma vez que ambos os grupos utilizaram o mesmo serviço de saúde, com a característica de alto risco. Os níveis de ácido fólico sérico, em um grupo, das mulheres estudadas, mantiveram-se normais e mais elevados dos que os estudos científicos publicados até o momento com semelhantes características. A prevenção com o uso do ácido fólico deve ser intensificada pelos vários setores da sociedade, ao grupo de risco estudado, para evitarmos assim a recorrência do defeito do tubo neural, reduzindo a incidência e recorrência em mulheres que tem maior chance de gerarem conceptos com essa malformação.
75

Profiling children with neural tube defects and exploring experiences of mothers

Simpamba, Micah Mutuna January 2012 (has links)
Magister Scientiae (Physiotherapy) - MSc(Physio) / Neural tube defects (NTDs) are the world‘s second most common birth defects after cardiovascular defects. In developing countries, poor access to health care services among children with NTDs contributes to early infant deaths, while those who survive live with severe disabilities. In Zambia, all children with NTDs in need of surgery are referred to Lusaka and physiotherapy services are not available in health facilities below the first level hospitals. The aim of the current study was to determine the profile of children with NTDs and to explore the experiences of mothers with accessing health care services for these children. The study which was conducted at the University Teaching Hospital (UTH) in Lusaka consisted of both quantitative and qualitative methods. The quantitative phase consisted of a retrospective record review of children with NTDs, who were admitted to UTH from January to December, 2010. A sample of 50 medical records was used based on available records, and data collection was done using a data extraction sheet which was specifically designed for the study. Analysis of quantitative data was done using Statistical Package for Social Science (SPSS) version 20.0. The qualitative phase had two parts, with the first part involving in-depth interviews with a purposefully selected sample of 20 mothers of children who were admitted to UTH. The second part used a sample of convenience of four mothers who had brought their children for follow up visits. All interviews were audiotaped, transcribed verbatim and translated, and recurring ideas were coded and collapsed into categories and themes. Permission to conduct the study was obtained from the UWC Research Grant and Study Leave Committee, University of Zambia Research Ethics Committee, and University Teaching Hospital management. Informed written consent was obtained from the mothers who accepted to take part in the study. Results from the record review revealed that the majority of children were from Lusaka province, with ages ranging from one day to 48 months and a male predominance of 58%. Myelomeningocele was the most common type of NTD (44%) with the lumbar region being the common site (52%). Hydrocephalus was present in 74% of children, 30% of children had both paraplegia and incontinence and 22% (n=11) of the files had no information on the neurological impairments. Wound infection was present in 40% (n=20) of the children. The majority (66%) of children were lost to follow up. Mothers of children who were admitted in UTH cited transport to UTH and back home as the main challenge. Other challenges included the lack of a prenatal diagnosis, the need for information, uncertainty about future of their children, and concerns about their family. Interviews with mothers on experiences with accessing physiotherapy services found that the lack of knowledge among mothers was the main reason children were not accessing physiotherapy services. Findings on access to health care were related to the ―Four A‘s‖ access theory which consists of four dimensions of access namely geographical accessibility, availability, affordability and acceptability. It is recommended that health care providers and policy makers ensure that all children with NTDs are provided with free transport to and from referral hospitals. Policy makers need to consider involving physiotherapists in out-reach programmes and mobile clinics to ensure access to physiotherapy services for all children in need of the service. Health care providers must also ensure that they give adequate information to mothers of children born with birth defects as this enhances their access to appropriate health care services.
76

Caracterização da população de recém-nascidos com diagnóstico de encefalocele / Characterization of the population of newborns diagnosed with encephalocele

Zomignani, Andrea Peterson, 1979- 22 August 2018 (has links)
Orientadores: Sergio Tadeu Matins Marba, Helder José Lessa Zambelli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-22T03:05:39Z (GMT). No. of bitstreams: 1 Zomignani_AndreaPeterson_M.pdf: 1128762 bytes, checksum: 59ae9805910c4b220c7bfa8d2e7bcbab (MD5) Previous issue date: 2012 / Resumo: Objetivo: Descrever uma população de recém-nascidos com encefalocele. Método: Estudo restrospectivo, descritivo e analítico por análise dos prontuários de recém-nascidos com diagnóstico de encefalocele, no Hospital da Mulher Prof. Dr. José Aristodemo Pinotti - Centro de Atenção Integral à Saúde da Mulher (CAISM), da Universidade Estadual de Campinas (UNICAMP). Foram incluídos todos os pacientes nascidos com diagnóstico de encefalocele no período de janeiro/1997 a julho/2008. Foram estudados: idade materna, paridade, pré-natal, apresentação fetal, tipo de parto, sexo, idade gestacional, índice de Apgar, peso, tipo de encefalocele, tratamento cirúrgico, ocorrência de óbitos, período de internação e retardo do desenvolvimento neuropsicomotor (RDNPM). Foram calculadas as frequências para cada variável analisada e a associação entre algumas variáveis foi verificada estatisticamente pelos testes qui-quadrado e exato de Fisher, considerando alfa de 5%. Resultados: Foram analisados 43 casos com prevalência de 1,24/1000 nascimentos. A faixa de idade materna de maior ocorrência foi 18 a 32 anos (83%), em mães não primigestas (65%), que fizeram os exames pré-natais (95%). A apresentação fetal mais recorrente foi cefálica (45%) com parto cesáreo (65%). Foram encontrados mais casos em meninas, com idade gestacional _37 semanas, tendo a maioria das crianças com a malformação nascido a termo (79%). No primeiro minuto houve Apgar menor ou igual a 7 em 58% dos casos. Em 67% dos casos o peso foi adequado, 27% foram baixo peso e 4,6% muito baixo peso. O tipo de encefalocele mais prevalente foi occipital e em 67% dos casos houve cirurgia. O óbito ocorreu em 31% dos recém nascidos e 55% tiveram período de internação de 1 a 15 dias. Em 62% dos casos foi descrito retardo do desenvolvimento neuropsicomotor. Conclusões: A prevalência de encefalocele foi de 1,24/1000 nascimentos e esteve associada às mães jovens e não primigestas. A apresentação cefálica foi à apresentação mais comum e o tipo de parto mais frequente foi parto cesáreo. Foi mais comum a presença de encefalocele em meninas, com idade gestacional _37 semanas, em nascidos a termo, com índice de Apgar baixo e com peso adequado. A maioria teve encefalocele occipital e precisou de cirurgia, sendo a taxa de mortalidade alta. Na maioria dos casos houve RDNPM / Abstract: Objective: To describe a serie of newborns with encephalocele. Method: Retrospective, descriptive and analytical study, with medical records analysis of newborns with encephalocele, born at the Hospital da Mulher Prof. Dr. José Aristodemo Pinotti - Center for Integral Assistance to Women's Health at the University of Campinas (UNICAMP). All the patients born with these conditions were selected from January/1997 until July/2008. It was studied: maternal age, parity, prenatal care, fetal presentation, mode of delivery, gender, gestational age, Apgar score, birth weight, type of encephalocele, surgical treatment, occurrence of death, hospitalization period, delayed neuropsychomotor development. Frequencies were calculated for each variable and the association among then were assessed statistically using the chi-square and Fisher exact test, considering a 5% alpha. Results: There were 43 cases with prevalence of 1,24/100 births. Maternal age range most frequent was 18 to 32 years (83%), in not primigravidae (65%), who made the prenatal care (95%). The most recurrent fetal presentation was cephalic (45%) with cesarean sections (65%). More cases were found in girls, with gestational age _37 weeks, with the majority of infants with malformations born at term (79%). First minute Apgar score was less than or equal to 7 in 58% of the cases. In 67% of the cases the weight was appropriate, 27% were low birth weight, and 4,6% were very low birth weight infants. The most prevalent type of encephalocele was occipital; 67% of the cases were underwent the surgery. Death occurred in 31% of the newborns and hospitalization period, in most cases, was 1 to 15 days. Neuropsychomotor development delay was observed in 62% of the cases. Conclusions: The prevalence of encephalocele was 1,24/1000 births and there was associated with young mothers and not primiparous. The cephalic presentation was common and there were more cesarean sections. It was more common the presence of encephalocele in girls, with gestational age _37 weeks in term newborns with low Apgar score and appropriate weight. Most had occipital encephalocele and needed surgery, and there was a high mortality rate. In most cases there were neurological deficit / Mestrado / Saude da Criança e do Adolescente / Mestra em Ciências
77

Valproic Acid Leads to an Increase in ROS Generation by Inhibiting the Deacetylation of Mitochondrial SOD

Lucas, Stephen Marc 03 August 2020 (has links)
Valproic Acid Promotes Acetylation of Superoxide Dismutase-2 During Neurogenesis. Valproic acid (VPA) is a known developmental toxicant associated with a high prevalence of neural tube defects (NTD). The mechanism of VPA-induced NTD is unclear, but oxidative stress may be implicated. To understand how embryotoxic oxidative stress may occur, we measured superoxide dismutase (SOD) activity following VPA treatment in the embryonic pluripotent P19 mouse carcinoma cell line. In undifferentiated P19 cultures treated with VPA (5 mM), dichlorofluorescein fluorescence increased 15% compared to untreated controls over 20 min, indicating a modest, yet statistically significant increase in ROS generation. Undifferentiated P19 cells were treated with VPA for 6 h, after which total SOD and mitochondrial SOD (SOD2) activities were measured. VPA treatment decreased total SOD activity by approximately 20% but SOD2 activity was undetectable; but this was not a consequence of changes to SOD (SOD1 or SOD2) protein concentrations. Interestingly, glutathione redox state increased from -262 mV to -245 mV after a 6 h treatment with VPA, indicating significant oxidation of the cellular redox environment. Measurement of mitochondrial superoxide levels showed an increase following VPA treatments. While it is unlikely that VPA works directly as an oxidant, these data suggest that VPA may promote oxidative stress through an alternative means, such as via the inhibition of SOD activity and thus, allow for an increase in ROS. Importantly, VPA is a known deacetylase inhibitor, and SOD2 function is regulated by acetylation. As such, we evaluated the acetylation state of SOD2 to determine potential disruption via acetylation. Treated undifferentiated P19 cells showed a significant increase in SOD2 acetylation. However, in fully differentiated P19-derived neurons, cells showed no such SOD2 acetylation. Additionally, pretreatment with dithiole-3-thione (D3T), a Nrf2 activator of the antioxidant response, attenuated VPA-induced mitochondrial ROS production and SOD2 acetylation and improved SOD2 activity, suggesting Nrf2 as a potential means to reduce VPA-mediated oxidative stress. To evaluate the effects in the embryo proper, gestational day 8 mouse embryos were treated with VPA in culture for 6 h. Similar to P19 cells, VPA-treated neurulating embryos showed significant SOD2 acetylation and a concomitant decrease in total SOD activity. These data support a similar consequence of VPA-induced oxidative stress in embryos as is demonstrated in our cellular model. Since no SOD2 acetylation is observed in differentiated neurons and VPAinduced SOD2 acetylation occurs more prevalently in undifferentiated/differentiating cells, these data purport means by which VPA preferentially induces oxidative stress in developing systems.
78

The prevalence of neural tube defects and the outcome of myelomeningocele in Cape Town

Buccimazza, Sandro Sabatino 07 April 2017 (has links)
This study was designed to document the prevalence of neural tube defects in Cape Town and to determine the outcome of children born with a myelomeningocele and operated on within the Neurosurgical service of the University of Cape Town. The aim of the prevalence study was to document the frequency of neural tube defects (NTD) over a twenty year period in Cape Town (1973 - 1992) and to determine the effects of race, gender, maternal age, parity, and season of conception on the prevalence. Multiple sources of ascertainment were used, including all maternity hospital records, neurosurgical and spinal defects clinic data, as well as those from the Human Genetics Department and Fetal Abnormality Group. The prevalence rates for NTD fluctuated between 1,74 and 0,63 per 1 000 births, but showed no significant trends over the twenty year period. Prevalence rates were highest for the white population group at 2,56 per 1 000 births compared to 0,95 per 1 000 for blacks and 1,05 per 1 000 for those of mixed ancestry. The higher rates in the whites, who are of British and European extraction and belong to the more affiuent section of the community, would suggest that the possible effects of nutrition and infection are overshadowed by genetic factors. There was a female preponderance for both spina bifida (M:F ratio 0,89) and anencephaly (M:F ratio 0,67). The highest NTD rates were found at both ends of the maternal age range (<20 years and >35 years of age). The prevalence was highest at the extremes of birth order (1,65 and 1,58 for birth order 1 and >7, respectively, and 0,56 and 0,45 for birth order 5 and 6, respectively). A seasonal variation occurred which differed from that reported for the Northern Hemisphere and may reflect local climatic conditions. The aim of the outcome study was to follow a group of infants who were operated on for myelomeningocele (01 January 1979 - 31 December 1985) and evaluate their outcome at five years of age, in an attempt to identify factors that may influence the quality of survival and their outcome, and to utilise these findings to recommend altering and improving ( where possible) the management of children born with myelomeningocele.
79

The Role of Pax3 in Neuronal Differentiation of the Ophthalmic (OpV) Trigeminal Placode and Neural Tube during Chicken Embryonic Development

Bradshaw, James R. 16 March 2006 (has links) (PDF)
Pax3 has been used as a valuable marker in research aimed at understanding tissue interactions involved in trigeminal ophthalmic (opV) placode development. While Pax3 expression coincides with opV neuron specification, the function of Pax3 in these cells has not previously been investigated. Splotch mutant mice (which lack Pax3) have a reduced trigeminal ganglion; however it is not clear whether this reduction is due to neural crest or placode cells. We have used electroporation in the chick model system to block or ectopically express Pax3 at key times in opV placode development. Using several markers of placode cell differentiation, we have determined the experimental effects manipulating Pax3. Blocking placodal Pax3 with gene specific morpholinos resulted in a loss of migratory placode cells, and a downregulation of all opV placode markers in targeted cells. Ectopic expression of Pax3, either within the placode domain or in adjacent cranial ectoderm, resulted in the upregulation of some but not all placode markers. We conclude that opV placodal Pax3 expression is required for normal placode cell development, and hypothesize that its expression must be tightly regulated in order for placode cells to fully differentiate. The precise role of Pax3 and Pax7 in the restriction and differentiation of dorsal interneuron progenitors has been difficult to assess due to the many additional factors involved in specification and patterning of the neural tube. We have used electroporation in the chick model system to ectopically express Pax3 and Pax7 unilaterally in the neural tube. Using several markers for differentiation of ventral and dorsal neuronal progenitors, we have experimentally determined the effects of Pax3 and Pax7 ventrally and dorsally. Ectopic expression of these transcription factors in the ventral neural tube resulted in the loss of motorneurons. Though mis-expression did not qualitatively affect commissural neurons as assayed by neurofilament staining, ectopic expression of Pax3 and Pax7 in the dorsal neural tube stopped dorsal interneuron progenitors from differentiating. We conclude that Pax3 and Pax7 expression is sufficient to restrict ventral neuron identity. We also hypothesize that downregulation of these transcription factors in the dorsal neural tube is required for normal dorsal interneuron differentiation.
80

Wnt5a Signaling Independently of the Planar Cell Polarity Pathway Resulting in Convergent Extension and Neural Tube Closure During Vertebrate Development

Barrott, Jared James 14 August 2008 (has links) (PDF)
Vertebrate development is regulated by cellular communication by mechanisms of cell fate and cell behavior. These crucial mechanisms are regulated by cellular signaling and in the case of cell fate, cellular signaling results in transcription of developmentally important genes. Communication between cells can also result in regulation of cell behavior by acting on cytoskeletal elements rather than nuclear factors. One of the cellular signals that regulate both cell fate and cell behavior is the family of Wnt signaling molecules. Wnt5a is one of 19 Wnt molecules and has been previously demonstrated to play critical roles in many important processes in embryonic development as well tumor suppression. Despite many studies that lend credence to a pathway that regulates cell behavior for Wnt5a rather than cell fate, the identity of the pathway(s) Wnt5a impinges upon remains unclear. Despite the possibility of Wnt5a signaling through multiple pathways, here, focus is given to the non-canonical Wnt signaling pathway, a pathway that regulates cell behavior, also known as the Wnt/Planar Cell Polarity (PCP) pathway. The involvement of Wnt5a in the Wnt/PCP pathway was demonstrated with a genetic approach: crossing Wnt5a heterozygous mice with mice heterozygous for a component of the Wnt/PCP pathway to uncover genetic interactions in vivo. Hence, Wnt5a X Looptail (Lp) (Wnt/PCP) heterozygous crosses have been performed. Double heterozygotes for this intercross did not exhibit a decrease in viable progeny as compared to the decreased numbers of Lp heterozygotes. These observations demonstrated a lack of genetic interaction between Wnt5a and the PCP pathway. Wnt5a mutants possess phenotypes associated with deficits in the Wnt/PCP pathway, namely convergent extension (CE) defects and neural tube closure defects. However, upon further investigation of the increased penetrance of craniorachischisis in Wnt5a-/-;Lp+/-, Wnt5a mutants do not display the characteristic broadening of the neural floor plate commonly associated with Lp-/-. This supports that Wnt5a and PCP signaling are parallel pathways that have converged to regulate different aspects of CE and neural tube closure. Despite the complexity of Wnt5a and its potential involvement in multiple pathways, dissection of this will explain the broad range of phenotypes observed.

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