Objetivo: Realizar a caracterização molecular dos genes C1q, C4 e C2 em pacientes com lúpus eritematoso sistêmico juvenil (LESJ). Métodos: Quatro pacientes com LESJ e deficiências de C1q,C4 e/ou C2 foram selecionados. O paciente P1 apresentava níveis séricos indetectáveis de C1q e níveis normais de C3 e C4; paciente P2 níveis baixos de C2 e C4 no soro; P3 apresentava níveis baixos de C2 e normais de C3 e C4 e P4 constantes níveis baixos de C4 e níveis normais de C1q, C2 e C3 no soro. Foram sequenciados os genes C1q e C2. Células mononucleares dos pacientes P1, P3 e P4 e de três indivíduos saudáveis foram cultivadas, estimuladas com interferon gama e incubadas por 36 horas e PCR quantitativo (qRTPCR) foi realizado para verificar a expressão de mRNA. Resultados: A caracterização molecular do gene C1q (P1) mostrou trocas heterozigotas na cadeia A (c.276 A>G Gly) e na cadeia C (c.126 C>T Pro). Foram observadas também duas trocas de base em homozigose na região 5\'UTR (c. -159 T>G) e na região 3\'UTR (c*78 A>G) da cadeia B. O qRT-PCR mostrou que a expressão de mRNA de C1qA no paciente P1 sem estimulo estava 1,3 vezes mais baixo e com estímulo de interferon gama estava 1,6 vezes mais expresso se comparado aos indivíduos saudáveis. A expressão de mRNA de C1qB sem estímulo foi 2,2 vezes mais baixo e com estímulo foi 1,5 vezes mais expresso quando comparados aos controles. Para C1qC os indivíduos controles não expressaram mRNA porém o paciente P1 apresentou pequena expressão com e sem estímulo. O sequenciamento do gene C2 dos pacientes P2 e P3 apresentou 100% de similaridade com a sequência de referência com exceção da deleção de 28pb no exon 6 (deficiência heterozigota de C2 do tipo I). A expressão de mRNA de C2 do paciente P3 foi sem estímulo 23 vezes mais baixo e com interferon 4,2 vezes menos expresso quando comparado aos controles. P4 apresentou 2 copias de C4A e 3 copias de C4B e no qRT-PCR o gene C4B estava 14 vezes menos expresso sem estímulo e com estímulo estava semelhante aos controles. Conclusões: As trocas de base em homozigose nas regiões 5\'UTR (região promotora) e 3\'UTR (região de estabilização do mRNA) na cadeia B do gene C1q podem ter modificado a região de transcrição do mRNA pois sua expressão sem estimulo foi baixa. Outras investigações são necessárias para relacionar as variações do gene C1q encontradas com os níveis séricos indetectáveis de C1q. A deficiência de C2 do tipo I heterozigota pode levar a redução na expressão de mRNA e pode estar presente em pacientes lúpicos com níveis séricos detectáveis de C2. Por fim, a baixa expressão de mRNA de C4B mostrou que as dosagens séricas e a avaliação do número de copias podem não ser suficientes para estabelecer a deficiência de C4 / Objective: To perform the molecular characterization of C1q, C4 and C2 genes in patients with Juvenile Systemic Lupus Erythematosus (JSLE). Methods: Four patients with JSLE and C1q, C4 and/or C2 deficiencies were chosen. Patient P1 had undetectable C1q serum level and normal levels of C3 and C4; Patient P2 had decreased levels of C2 and C4 serum while P3 had decreased C2 with normal C3 and C4 levels. Lastly P4 had repeated decreased C4 and normal C1q, C2 and C3 serum levels. C1q and C2 genes were sequenced. Peripheral mononuclear cells from patients P1, P3 and P4 and from three healthy individuals were both cultivated and stimulated with interferon gamma and a quantitative PCR (qRT-PCR) was also performed to verify mRNA expression. Results: C1q molecular characterization for P1 revealed heterozygous silent mutations in A chain (c.276 A>G Gly) and in C chain (c.126 C>T Pro). Additionally, in B chain two homozygous single-base exchanges were detected in the 5´UTR (c. -159 T>G) and 3\'UTR region (c*78 A>G). The qRTPCR revealed that C1qA gene mRNA expression without stimulation was decreased 1.3 times and with interferon gamma was 1.6 times more expressed compared with controls samples. C1qB gene expression without stimulation was 2.2 times decreased and when stimulated was 1.5 times more expressed. Controls did not expressed C1qC gene and patient P1 had low expression both with and without stimulation. P2 had 2 copies of C4A and 1 copy of C4B. C2 gene sequencing (P2 and P3) showed 100% match with referenced sequence, with exception to 28bp deletion at the exon 6 (heterozygous C2 deficiency type I). C2 mRNA expression from P3 without stimulation was 23 times decreased and with interferon was 4.2 times decreased compared with controls. P4 had 2 copies of C4A and 3 copies of C4B. The qRT-PCR were performed only in C4B gene showed without stimulation a 14 times decreased expression and with interferon stimulation the expression were similar to controls. Conclusions: The two homozygous single-base exchanges in 5\'UTR and 3\'UTR that correspond to the promoter region and stabilization mRNA region in B chain of C1q gene, may have modified mRNA transcription as its expression was decreased without stimulation. Further analysis is necessary to relate C1q gene variations and undetectable serum C1q. In addition, heterozygous C2 deficiency type I may lead to reduced mRNA expression and may be present in JSLE patients with detectable C2 levels. Finally, the decreased C4B gene expression showed that serum dosage and gene copy number may not be sufficient to assess C4 deficiency

Objetivo: Realizar a caracterização molecular dos genes C1q, C4 e C2 em pacientes com lúpus eritematoso sistêmico juvenil (LESJ). Métodos: Quatro pacientes com LESJ e deficiências de C1q,C4 e/ou C2 foram selecionados. O paciente P1 apresentava níveis séricos indetectáveis de C1q e níveis normais de C3 e C4; paciente P2 níveis baixos de C2 e C4 no soro; P3 apresentava níveis baixos de C2 e normais de C3 e C4 e P4 constantes níveis baixos de C4 e níveis normais de C1q, C2 e C3 no soro. Foram sequenciados os genes C1q e C2. Células mononucleares dos pacientes P1, P3 e P4 e de três indivíduos saudáveis foram cultivadas, estimuladas com interferon gama e incubadas por 36 horas e PCR quantitativo (qRTPCR) foi realizado para verificar a expressão de mRNA. Resultados: A caracterização molecular do gene C1q (P1) mostrou trocas heterozigotas na cadeia A (c.276 A>G Gly) e na cadeia C (c.126 C>T Pro). Foram observadas também duas trocas de base em homozigose na região 5\'UTR (c. -159 T>G) e na região 3\'UTR (c*78 A>G) da cadeia B. O qRT-PCR mostrou que a expressão de mRNA de C1qA no paciente P1 sem estimulo estava 1,3 vezes mais baixo e com estímulo de interferon gama estava 1,6 vezes mais expresso se comparado aos indivíduos saudáveis. A expressão de mRNA de C1qB sem estímulo foi 2,2 vezes mais baixo e com estímulo foi 1,5 vezes mais expresso quando comparados aos controles. Para C1qC os indivíduos controles não expressaram mRNA porém o paciente P1 apresentou pequena expressão com e sem estímulo. O sequenciamento do gene C2 dos pacientes P2 e P3 apresentou 100% de similaridade com a sequência de referência com exceção da deleção de 28pb no exon 6 (deficiência heterozigota de C2 do tipo I). A expressão de mRNA de C2 do paciente P3 foi sem estímulo 23 vezes mais baixo e com interferon 4,2 vezes menos expresso quando comparado aos controles. P4 apresentou 2 copias de C4A e 3 copias de C4B e no qRT-PCR o gene C4B estava 14 vezes menos expresso sem estímulo e com estímulo estava semelhante aos controles. Conclusões: As trocas de base em homozigose nas regiões 5\'UTR (região promotora) e 3\'UTR (região de estabilização do mRNA) na cadeia B do gene C1q podem ter modificado a região de transcrição do mRNA pois sua expressão sem estimulo foi baixa. Outras investigações são necessárias para relacionar as variações do gene C1q encontradas com os níveis séricos indetectáveis de C1q. A deficiência de C2 do tipo I heterozigota pode levar a redução na expressão de mRNA e pode estar presente em pacientes lúpicos com níveis séricos detectáveis de C2. Por fim, a baixa expressão de mRNA de C4B mostrou que as dosagens séricas e a avaliação do número de copias podem não ser suficientes para estabelecer a deficiência de C4 / Objective: To perform the molecular characterization of C1q, C4 and C2 genes in patients with Juvenile Systemic Lupus Erythematosus (JSLE). Methods: Four patients with JSLE and C1q, C4 and/or C2 deficiencies were chosen. Patient P1 had undetectable C1q serum level and normal levels of C3 and C4; Patient P2 had decreased levels of C2 and C4 serum while P3 had decreased C2 with normal C3 and C4 levels. Lastly P4 had repeated decreased C4 and normal C1q, C2 and C3 serum levels. C1q and C2 genes were sequenced. Peripheral mononuclear cells from patients P1, P3 and P4 and from three healthy individuals were both cultivated and stimulated with interferon gamma and a quantitative PCR (qRT-PCR) was also performed to verify mRNA expression. Results: C1q molecular characterization for P1 revealed heterozygous silent mutations in A chain (c.276 A>G Gly) and in C chain (c.126 C>T Pro). Additionally, in B chain two homozygous single-base exchanges were detected in the 5´UTR (c. -159 T>G) and 3\'UTR region (c*78 A>G). The qRTPCR revealed that C1qA gene mRNA expression without stimulation was decreased 1.3 times and with interferon gamma was 1.6 times more expressed compared with controls samples. C1qB gene expression without stimulation was 2.2 times decreased and when stimulated was 1.5 times more expressed. Controls did not expressed C1qC gene and patient P1 had low expression both with and without stimulation. P2 had 2 copies of C4A and 1 copy of C4B. C2 gene sequencing (P2 and P3) showed 100% match with referenced sequence, with exception to 28bp deletion at the exon 6 (heterozygous C2 deficiency type I). C2 mRNA expression from P3 without stimulation was 23 times decreased and with interferon was 4.2 times decreased compared with controls. P4 had 2 copies of C4A and 3 copies of C4B. The qRT-PCR were performed only in C4B gene showed without stimulation a 14 times decreased expression and with interferon stimulation the expression were similar to controls. Conclusions: The two homozygous single-base exchanges in 5\'UTR and 3\'UTR that correspond to the promoter region and stabilization mRNA region in B chain of C1q gene, may have modified mRNA transcription as its expression was decreased without stimulation. Further analysis is necessary to relate C1q gene variations and undetectable serum C1q. In addition, heterozygous C2 deficiency type I may lead to reduced mRNA expression and may be present in JSLE patients with detectable C2 levels. Finally, the decreased C4B gene expression showed that serum dosage and gene copy number may not be sufficient to assess C4 deficiency

This parallel randomized control trial study assessed the effect of food-based strategies in improving the haemoglobin level; decreasing anaemia and thus the iron status of pregnant women. The study randomized 195 anaemic women enrolled from four randomly selected health centres in Dire Dawa while attending ANC into two intervention groups and control; and followed for 12weeks. The study intervened diet-based supplementation of 90mg/day vitamin C divided and consumed in three doses; combined with nutrition education intervention in intervention group 1; while only nutrition education intervention in group 2. Dietary diversity was assessed using past 24-hours and 7-days dietary recall approaches and haemoglobin levels were determined at baseline and end-line and compared to analyse treatment effects. By end of the study, intervention group 1 and 2 had significantly increased mean haemoglobin by 0.77 ± 0.11gm/dl and 0.398 ± 0.073gm/dl respectively; however, the control had significant decrease by -0.193 ± 0.05gm/dl. Anaemia prevalence also significantly decreased by 29% and 19.7% in intervention group 1 and 2 respectively. However, all women in the control were anaemic. Intervention group 1 and 2 also had significantly higher dietary diversity, consumption of vitamin C-rich fruits and vegetables, nutritional knowledge and modification practices. The researcher thus concludes that diet-based vitamin C supplementation integrated with nutrition education has a significant effect in improving haemoglobin, decreasing anaemia and thus improving the iron status of pregnant women in Dire Dawa. Based on the findings, the researcher developed a framework for an integrated food-based strategy for improving the iron status of pregnant women in Ethiopia. / Health Studies / D. Litt. et Phil. (Health Studies)

Background: Growth hormone (GH) has been used to treat children with GH deficiency (GHD) since 1966. Aims: Using a combined retrospective and cross-sectional approach, we explored the long-term outcomes of patients with GHD, analysed factors influencing therapeutic response, determined persistence into adulthood, investigated pituitary morphology, and screened for mutations in causative genes. Methods: The files of 96 GH-deficient children were reviewed. In a subset of 50 patients, re-assessment in adulthood was performed, including GHRH-arginine testing, pituitary magnetic resonance imaging (MRI), and mutational screening for the growth hormone-1 gene (GH1) and the GHRH receptor gene (GHRHR) in isolated GHD (IGHD), and HESX1 , PROP1 , POU1F1 , LHX3 , LHX4 , and GLI2 in multiple pituitary hormone deficiency (MPHD) patients. Results: GH was started at a height SDS of –3.2 ± 1.4 in IGHD patients and of –4.1 ± 2.1 in MPHD patients. Relative height gain was 0.3 SDS/year, absolute gain 1.6 SDS, and 1.2/2.6 SDS in IGHD/MPHD, respectively. Mid-parental target height was reached in 77%. Initial height SDS, bone age retardation and duration of GH replacement were correlated with height SDS gain. GHD persisted into adulthood in 19 and 89% of subjects with IGHD and MPHD, respectively. In 1/42 IGHD patients a GH1 mutation was detected; PROP1 mutations were found in 3/7 MPHD subjects. Anterior pituitary hypoplasia, combined with posterior pituitary ectopy and pituitary stalk invisibility on MRI, was an exclusive finding in MPHD patients. Conclusions: GH replacement successfully corrects the growth deficit in children with GHD. While the genetic aetiology remains undefined in most cases of IGHD, PROP1 mutations constitute a major cause for MPHD. Persistence of GHD into adulthood is related to abnormal pituitary morphology.

Introdução: A anemia afeta 273 milhões (43 por cento) de crianças pré-escolares em todo o mundo e constitui-se uma prioridade mundial dado seu risco para morbidade infantil, prejuízo no desenvolvimento e repercussões na vida adulta. A fortificação caseira (FC) com múltiplos micronutrientes em pó (MNP) consiste em uma das estratégias mais promissoras para reduzir anemia e deficiência de micronutrientes em crianças de 6 a 23 meses. Contudo, a baixa adesão tem sido uma barreira para o seu sucesso. Poucos são os estudos que têm avaliado os fatores que influenciam a adesão ao uso dos MNP a fim de melhorar a efetividade de sua implementação. Objetivo: Avaliar o impacto da FC com MNP na anemia e deficiência de micronutrientes em crianças do município de Rio Branco, Acre, bem como a aceitação delas e os fatores associados à adesão dos cuidadores à intervenção. Métodos: Esta investigação integra o Estudo Nacional de Fortificação caseira da Alimentação Complementar (ENFAC), estudo multicêntrico realizado nos anos de 2012 e 2013 em quatro cidades brasileiras (Rio Branco, Olinda, Goiânia e Porto Alegre), cujo delineamento foi do tipo ensaio clínico pragmático controlado em Unidades Básicas de Saúde (UBSs). Para a presente análise, foram considerados dados da cidade de Rio Branco Acre. No início do estudo, 150 crianças de 11 a 14 meses de idade foram recrutadas para composição do grupo controle (GC), na rotina de puericultura. Simultaneamente, e nas mesmas UBSs, 126 crianças de 6 a 8 meses de idade compuseram o grupo intervenção (GI) para receber FC com MNP adicionado diariamente na alimentação complementar (AC). A efetividade dos MNP foi avaliada comparando-se os grupos após 4-6 meses do início da intervenção, com os participantes do GI estando com a mesma idade do GC (11 a 14 meses). Os desfechos de interesse foram prevalências de anemia, DF, DVA, e outros micronutrientes; indicadores bioquímicos de inflamação e morbidades bem como o impacto do uso da fortificação nesses indicadores nutricionais e os fatores que influenciaram a adesão ao uso do sachê com MNP. Utilizaram-se teste de qui-quadrado de Pearson, teste de t Student ou de Mann-Whitney U e modelos de regressão de Poisson. Resultados: Os fatores associados à prevalência de anemia e o risco para esse desfecho foram: mãe ter mais de um filho [razão de prevalência (RP) (IC 95 por cento): 2,11 (1,06; 4,19)], ausência de TV a cabo ou internet no domicílio (como marcador de riqueza) [4,57 (1,13; 18,47)] e presença de desnutrição (escore Z do índice altura/idade <-2) [2,28 (1,28; 4,09)]. Introdução tardia de alimentos ricos ou promotores da absorção do ferro (ITARPAF) [1,92 (1,10; 3,37)], presença de inflamação/infecção [2,21 (1,38; 3,54)] e deficiências de vitaminas A [1,85(1,05; 3,28)] e B12 [1,90 (1,05; 3,46)] também relacionaram-se a > prevalência de anemia nas crianças estudadas. A respeito da DF, entre crianças cujas mães possuíam maior escolaridade a deficiência foi 17 por cento menor comparadas àquelas com menor escolaridade. A ITARPAF representou risco 26 por cento maior de DF em relação aos que tiveram a AC introduzida oportunamente. A DVA também foi associada à maior DF [1,37 (1,17; 1,61)]. Após a fortificação com MNP, as crianças do GI mostraram um risco menor de DF (72,4 por cento versus 25,2 por cento), DVA (18,4 por cento vs 4,7 por cento), de insuficiência de vitamina E (73,4 por cento vs 33,6 por cento), de infecção (Proteína C-reativa>5 mg/l: 21 por cento vs 9,5 por cento; Alfaglicoproteína >1g/l: 41 por cento vs 26,7 por cento), tosse (68,8 por cento vs 37,5 por cento) e chiado no peito (46,1 por cento vs 8,9 por cento), quando comparadas com as crianças do GC. Embora a aceitabilidade ao sachê tenha sido considerada boa ou excelente por 65,5 por cento dos cuidadores, a adesão completa à estratégia (60 sachês em 2-3 meses) foi de apenas 29 por cento das crianças estudadas. Os fatores relacionados à baixa adesão ao uso do sachê com MNP foram: hospitalização da criança no ano anterior à pesquisa [RP (IC 95 por cento): 1,68 (1,14; 2,45)], ter mãe adolescente [1,48 (1,01; 2,18)] e introdução precoce de fórmula infantil [1,92 (1,13; 3,29)]; já as crianças que iniciaram a AC com fruta tiveram melhor adesão ao consumo do sachê [0,56 (0,34; 0,93)]. Conclusão: Em uma área com marcantes iniquidades sociais de acesso a bens e serviços e de alta carga de morbidade, nossos achados ratificam o papel das deficiências de micronutrientes e infecção no risco para anemia, DF e DVA. O aconselhamento nutricional permanente quanto às práticas alimentares saudáveis na infância deve ser integrado à estratégia do MNP a fim de reduzir DF, DVA e de outros micronutrientes, assim como algumas morbidades. A incorporação da fortificação com múltiplos micronutrientes em pó deve considerar uma atenção redobrada às mães adolescentes no serviço de atenção primária à saúde nesta região da Amazônia. / Background: Anemia affects 273 million (43 per cent) of preschoolers around the world and is a global priority given its risk for child morbidity, developmental impairment and repercussions in adult life. Home fortification (HF) with multiple micronutrients powder (MNP) consists in one of the most promising strategies to reduce micronutrient deficiency and anemia in children aged 6-23 months. However, the poor compliance has been a barrier to its success. Few studies have evaluated the factors that influence MNP adherence in order to improve the effectiveness of its implementation. Objective: To assess the impact of home fortification with MNP on anemia and deficiency of micronutrients in children as well as the acceptance of them and the factors associated to the caregivers adherence to the intervention. Methods: This research is part of the Estudo Nacional de Fortificação caseira da Alimentação Complementar (ENFAC), a multicentre pragmatic controlled clinical trial carried out in the years of 2012 and 2013 in Basic Health Units (BHUs) from four Brazilian cities (Rio Branco, Olinda, Goiânia e Porto Alegre). For the present analysis, data from the city of Rio Branco - Acre were considered. In the beginning of the study, 150 children aged 11 to 14 months were recruited for composition of control group (CG), in childcare routine. Simultaneously, and in the same BHUs, 126 children aged 6 to 8 months comprised the intervention group (GI) to receive HF with MNP added daily in the complementary feeding (CF). The effectiveness of MNP was evaluated by comparing the groups after 4-6 months of the beginning of the intervention, with the GI participants being of the same age as the CG (11 to 14 months). Outcomes of interest were prevalence of anemia, ID, VAD, and other micronutrients; biochemical indicators of inflammation and morbidities as well as the impact of the use of fortification on these nutritional indicators and the factors that influenced adherence to the sachet use with MNP. Pearsons 2 test, Students t test or the MannWhitney U test and Poisson regression models were used in the analysis. Results: The main factors that influenced the prevalence of anemia and the risk of this outcome were: the mother having more than one child [prevalence ratio (CI 95 per cent): 2.11 (1.06; 4.19)], living in households without access to cable TV or internet (as a marker of wealth) [4.57 (1.13; 18.47)] and presence of stunting (Z-scores for length/height for- age < -2) [2.28 (1.28; 4.09)]. Late introduction of iron-rich foods or which promote its absorption [1.92 (1.10; 3.37)], presence of inflammation/infection [2.21 (1.38; 3.54)] and vitamin A [1.85 (1.05; 3.28)] and vitamin B12 deficiencies [1.90 (1.05; 3.46)] were also related with > risk of anemia in the study children. Regarding ID, among children whose mothers had a higher level of schooling a 17 per cent lower risk was observed when compared to those with lower schooling. The late introduction of iron-rich foods represented a 26 per cent higher risk of ID in relation to those who had the CF introduced timely. The VAD was also associated with highest ID risk [1.37 (1.17; 1.61)]. The IG children after home fortification with MNP showed a lower risk of ID (72.4 per cent versus 25.2 per cent), VAD (18.4 per cent vs 4.7 per cent), of vitamin E insufficiency (73,4 per cent vs 33,6 per cent), of infection (C-reactive protein>5 mg/l: 21 per cent vs 9.5 per cent; 1-acid glycoprotein>1g/l: 41 per cent vs 26.7 per cent), cough (68.8 per cent vs 37.5 per cent) and wheezing (46.1 per cent vs 8.9 per cent), when compared with the CG children. Although the overall acceptability of the MNP sachet was considered good or excellent by 65.5 per cent of caregivers, the complete adherence to the strategy (60 sachets in 2-3 months) was reached in only 29 per cent of the study children. The main factors related to the low adherence to the use of the MNP sachet were: hospitalization of the child in the year prior to the survey [prevalence ratio (CI 95 per cent): 1.68 (1.14, 2.45)], having teenage mother [1.48 (1.01; 2.18)] and early introduction of infant formula [1.92 (1.13; 3.29)]; children who started timely the CF with fruits had better adherence to the sachet consumption [0.56 (0.34, 0.93)]. Conclusion: In an area with marked social inequities in access to goods and services and with high burden of morbidity, our findings confirm the role of micronutrient deficiencies and infection status in the risk for anemia, ID and VAD. The continuous nutritional counseling to promote healthy eating practices in childhood should be integrated to the MNP strategy for reducing ID, VAD and other micronutrient deficiencies, as well as some morbidities. The implementation of MNP fortification should consider an increased attention to adolescent mothers in the primary health care services in this Amazonian region.

As exogenously administered RA suppressed the expression of the RA synthesizing enzymes, further investigation on whether this would lead to deficiency in endogenous RA concentrations was conducted. Results showed that exogenously administered RA significantly reduced the endogenous RA level in the head region with C57 embryos showing a greater reduction than ICR embryos. / In addition, detailed morphological and histological studies were conducted to determine if RA treatment caused early embryonic changes with strain difference. When compared with ICR embryos, C57 embryos exhibited more pronounced responses to RA, including developmental retardation, underdevelopment of the anterior neural plate and absence of or smaller optic pit/optic vesicle formation. However, RA treatment did not cause abnormal apoptosis in the early stages in both strains. / Since the teratogenic effect of RA is highly developmental stage-dependent, it is possible that there is a difference in the developmental stage between these 2 mouse strains at the time of RA injection. Indeed, it was found that the developmental stage of ICR embryos was approximately 6 hours ahead of C57 embryos. However, the role that this factor plays in the differential strain susceptibility to RA can be excluded since C57 fetuses were still 3 times more susceptible to developing anophthalmia/microphthalmia than ICR fetuses that were subject to RA treatment at equivalent developmental stages. Comparison of susceptibility to RA-induced anophthalmia/microphthalmia was also made among heterozygous fetuses obtained from reciprocal matings between C57 and ICR male and female mice, and those in homozygous ICR and C57 fetuses. Results showed that the C57 strain has conferred both genetic predisposition and maternal effects in increasing the embryo's susceptibility to RA-induced ocular defects. / Since the type of RA-induced ocular defects mimic those that developed in Raldh2 null mutant embryos, the effect of RA treatment on the expression of RA synthesizing enzymes, Raldh2 and Raldh3, and the RA-inducible gene Cyp26a1, as well as some early eye development genes were examined. Exogenously administered RA reduced the mRNA expression levels of Raldh2, Raldh3 and Cyp26a1 in the head region, with C57 embryos showing a greater reduction than ICR embryos. / Taken together, results of this thesis suggest that there is a strain difference in susceptibility to RA-induced ocular defects in which exogenously applied RA suppresses the expression of RA synthesizing enzymes and leads to endogenous RA deficiency. This finding may shed light on understanding why both excess and deficiency of RA can lead to similar types of ocular defects. / To determine if there are strain differences in the susceptibility to RA-induced ocular defects, two mouse strains were used. They are C57BL/6J (C57), mice that spontaneously develop ocular defects and ICR mice, which are not prone to developing ocular defects. Detailed time and dose response studies were conducted and eye defects were examined in near-term fetuses. C57 fetuses were found to be significantly more susceptible to RA-induced anophthalmia/microphthalmia than ICR fetuses. / Vitamin A (retinol) and its most active metabolite, all- trans retinoic acid (RA) is essential for vision in the adult and for eye development in the embryo. It is well documented that in humans, excess intake or deficiency of vitamin A or RA is associated with congenital ocular defects such as microphthalmia. However, the underlying mechanism remains unclear. The aim of this study is to examine the pathogenic mechanism of RA-induced developmental ocular defects. / Lau, Wing Sze Josephine. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0240. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 186-211). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

Tang, Leung Sang Nelson. / "February 2002." / Thesis (M.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 185-206). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.

Leung, Yeung Yeung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 134-154). / Abstracts in English and Chinese. / CONTENTS --- p.i / ACKNOWLEDGEMENTS --- p.iv / ABSTRACT --- p.v / 論文摘要 --- p.viii / LIST OF FIGURES --- p.x / LIST OF TABLES --- p.xiv / LIST OF ABBREVIATIONS --- p.xv / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Brain iron function and diseases --- p.1 / Chapter 1.1.1 --- Function of iron in the brain --- p.1 / Chapter 1.1.2 --- Iron involved oxidative damage --- p.2 / Chapter 1.1.3 --- Role of iron in neurodegenerative diseases --- p.6 / Chapter 1.1.4 --- Role of iron in Alzheimer's disease --- p.7 / Chapter 1.1.5 --- Deleterious effects of iron in memory function --- p.9 / Chapter 1.2 --- Iron regulation in the brain --- p.10 / Chapter 1.2.1 --- Transport and storage of brain iron --- p.10 / Chapter 1.2.2 --- Iron homeostasis in the brain --- p.14 / Chapter 1.2.3 --- Transport of iron in axon and synapse --- p.17 / Chapter 1.3 --- The hippocampus --- p.19 / Chapter 1.3.1 --- Hippocampus and memory function --- p.19 / Chapter 1.3.2 --- Structure of the hippocampus --- p.20 / Chapter 1.3.3 --- Cell composition in the hippocampus --- p.26 / Chapter 1.3.4 --- Wiring in the hippocampus --- p.28 / Chapter 1.4 --- Synaptic plasticity and long term potentiation --- p.30 / Chapter 1.4.1 --- Basic theory of synaptic plasticity --- p.30 / Chapter 1.4.2 --- Types of synaptic plasticity --- p.30 / Chapter 1.4.3 --- The discovery of long term potentiation --- p.31 / Chapter 1.4.4 --- Long term potentiation --- p.32 / Chapter 1.4.5 --- Cellular mechanism of long term potentiation --- p.33 / Chapter 1.4.6 --- Role of reactive oxygen species in long term potentiation --- p.36 / Chapter 1.5 --- Aim of the study --- p.38 / Chapter 2. --- MATERIALS AND METHODS --- p.39 / Chapter 2.1 --- Rat model of iron overload --- p.39 / Chapter 2.2 --- Multi-electrode field potential measurement --- p.40 / Chapter 2.2.1 --- Acute preparation of hippocampal slices --- p.40 / Chapter 2.2.2 --- Multi-electrode array recording system --- p.41 / Chapter 2.2.3 --- Recording of field excitatory postsynaptic potentials --- p.42 / Chapter 2.2.4 --- Induction of LTP --- p.47 / Chapter 2.2.5 --- Recording of paired-pulse ratio --- p.48 / Chapter 2.3 --- Whole cell patch-clamp recordings --- p.50 / Chapter 2.4 --- Biochemical assays --- p.57 / Chapter 2.4.1 --- Preparation of brain homogenate --- p.57 / Chapter 2.4.2 --- Total iron measurement --- p.57 / Chapter 2.4.3 --- Protein carbonyl measurement --- p.58 / Chapter 2.4.4 --- Determination of reactive oxygen species --- p.60 / Chapter 2.5 --- Drugs and data analysis --- p.61 / Chapter 3. --- RESULTS --- p.62 / Chapter 3.1 --- The acute effects of extracellular iron on synaptic transmission and long-term synaptic plasticity in the hippocampus in vitro --- p.63 / Chapter 3.1.1 --- Effects of ferric ion on basal synaptic transmission --- p.63 / Chapter 3.1.1.1 --- Effect of FAC on basal fEPSPs --- p.63 / Chapter 3.1.1.2 --- Comparison with the effect of AC on basal fEPSPs --- p.69 / Chapter 3.1.2 --- Effects of ferric ion on long-term synaptic plasticity --- p.72 / Chapter 3.1.2.1 --- Effect of acute FAC treatment on LTP --- p.72 / Chapter 3.1.2.2 --- Comparison with the effect of AC on LTP --- p.75 / Chapter 3.1.3 --- Effects of ferric chloride --- p.78 / Chapter 3.1.4 --- Effects of ascorbic acid on the action of FAC --- p.81 / Chapter 3.2 --- "The acute, in vitro effect of extracellular iron on the membrane properties and excitability of hippocampal CA1 neurons" --- p.86 / Chapter 3.2.1 --- Membrane input resistance --- p.86 / Chapter 3.2.2 --- Voltage-Current relationship --- p.88 / Chapter 3.2.3 --- Membrane excitability --- p.90 / Chapter 3.2.3.1 --- Threshold current --- p.90 / Chapter 3.2.3.2 --- Action potential firing frequency --- p.92 / Chapter 3.2.4 --- Action potential characteristics --- p.95 / Chapter 3.2.4.1 --- "Action potential amplitude, area and width" --- p.95 / Chapter 3.2.4.2 --- Rise and decay kinetics of action potential --- p.98 / Chapter 3.3 --- The chronic effects of iron-loading in the brain on hippocampal long-term synaptic plasticity --- p.100 / Chapter 3.3.1 --- Validation of the iron-overload model --- p.100 / Chapter 3.3.1.1 --- Short-term (1 week) treatment --- p.100 / Chapter 3.3.1.2 --- Long-term (4 weeks) treatment --- p.103 / Chapter 3.3.2 --- Effects of chornic iron-overloading on LTP --- p.105 / Chapter 3.3.2.1 --- Short term iron treatment --- p.105 / Chapter 3.3.2.2 --- Long term iron treatment --- p.108 / Chapter 3.3.3 --- Oxidative stress measurement --- p.111 / Chapter 3.3.3.1 --- Protein oxidation --- p.111 / Chapter 3.3.3.2 --- Reactive oxidative species level --- p.116 / Chapter 4. --- DISCUSSION --- p.120 / Chapter 4.1 --- "Acute, in vitro effects" --- p.121 / Chapter 4.2 --- "Chronic, in vivo effects" --- p.125 / Chapter 5. --- REFERENCES --- p.134

A deficiência de CD40 Ligante (CD40L) ou síndrome de Hiper-IgM ligada ao X (X-HIGM) é considerada uma imunodeficiência primária combinada de células T e B. O CD40L é expresso na superfície de linfócitos T ativados e interage com o CD40 expresso na superfície de linfócitos B, macrófagos, células dendríticas, células endoteliais e neutrófilos. A interação CD40L-CD40 transmite sinais que induzem ativação, diferenciação e proliferação celular. Nosso objetivo foi analisar as alterações genético-moleculares da molécula CD40L que acometeram indivíduos de 5 famílias brasileiras, ocasionando X-HIGM. Genotipamos 25 indivíduos, sendo 6 pacientes com X-HIGM, 13 parentes relacionados heterozigotos e 6 homozigotos sadios. Dentre os pacientes com X-HIGM dois eram de origem caucasóide e 4 eram mestiços. A idade dos pacientes variou de 2 a 20 anos e o quadro clínico de infecções de repetição teve início em média nos primeiros 4 meses de vida. As principais infecções recorrentes manifestadas pelos pacientes foram pneumonia e otite. O paciente TB apresentou blastomicose, observação original nesta imunodeficiência. A análise genético-molecular foi heterogênea. No paciente TB foi detectado um defeito de splicing levando a deleção do exon 3 (r.345_402del do gene CD40L (CD40LG) no paciente FS uma nova substituição missense g.11856 G>C (c.476 G>C, pW140C), no paciente KC uma substituição nonsense g.11855 G>A (c.475G>A, p. W140X), e nos pacientes CH, FE e VIC uma deleção g. 3074_3077delTAGA, levando a alteração no processamento do RNA. A fenotipagem dos leucócitos demonstrou que a contagem de linfócitos T auxiliares (CD3+CD4+), linfócitos citotóxicos (CD3+CD8+), linfócitos B (CD19+CD40+) e linfócitos T ativados (CD3+CD69+) dos pacientes foram similares aos controles sadios. Contudo, foi observada uma redução significativa nos níveis de expressão de CD40L na superfície de linfócitos CD3+ e CD4+ dos pacientes. A análise dos linfócitos T por microscopia confocal revelou que as células dos homozigotos com expressão residual do CD40L em sua superfície também apresentam redução na densidade da expressão da molécula CD3, sugerindo a necessidade da integridade molecular do CD40L para a expressão normal do CD3. Concluímos que mutações no CD40L que levam à síndrome de X-HIGM são heterogêneas e a análise genético-molecular permitiu um diagnóstico preciso tornando possível o aconselhamento genético e a triagem dos recém-nascidos das famílias avaliadas. / CD40-Ligand (CD40L) deficiency or X linked Hyper-IgM syndrome (X-HIGM) is considered a T and B cell combined primary immunodeficiency. CD40L is expressed on the cell surface of activated T lymphocytes and interacts with CD40, expressed on the surface of B lymphocytes, macrophages, dendritic cells, endothelial cells, and neutrophils. The CD40L-CD40 interaction induces activation, differentiation, and cell proliferation. Our aim was to analyze the molecular-genetic alterations of CD40L molecule affecting individuals of 5 brazilian families, leading to X-HIGM. We genotyped 25 individuals, whom 6 were X-HIGM patients, 13 were heterozygote related patients, and 6 were healthy homozygotes. Within the patients with X-HIGM, two of them were of caucasoid origin and four were mestiços. The patients age ranged from 2 to 20 years and their recurrent infections started in average during their first 4 months of life. The main recurrent infections were pneumonia and otitis. The patient TB presented blastomycosis, a unique observation in this immunodeficiency. The molecular-genetic analysis revealed heterogeneity. TB patient presented a splicing defect causing a deletion of exon 3 (r.345_402del) of CD40L gene (CD40LG). Patient FS presented a new missense mutation g.11856 G>C (c.476 G>C, pW140C). Patient KC presented a nonsense substitution g.11855 G>A (c.475G>A, p. W140X). Patients CH, VIC, and FE presented a deletion g. 3074_3077delTAGA, causing an alteration on RNA processing. The leukocytes fenotyping demonstrated that T helper lymphocytes (CD3+CD4+), T cytotoxic lymphocytes (CD3+CD8+), B lymphocytes (CD19+CD40+), and T activated (CD3+CD69+) cell counts of patients were similar to healthy controls. However it was observed a significant reduction of CD40L expression on cell surface patients CD3+ and CD4+ lymphocytes. The T lymphocyte confocal microscopy analysis revealed that homozygotes with residual expression of CD40L in their surface also presented a reduction on the density of CD3 molecule expression, suggesting the need of molecular integrity of CD40L for normal CD3 expression. We conclude that mutations on CD40L leading to X-HIGM syndrome are heterogeneous and the molecular-genetic analysis allowed a precise diagnosis making possible the genetic counseling and newborn screening of the involved families.

Bibliography: leaves 148-163.