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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.
51

Fator de crescimento endotelial vascular (VEGF): concentrações séricas e teciduais em gestações ectópicas ampulares e a profundidade da invasão trofoblástica / Vascular endothelial growth factor (VEGF): Serum and tissue concentration in ampular pregnancies and the depth of trophoblastic invasion

Décio Roberto Kamio Teshima 11 November 2015 (has links)
Objetivo: Avaliar a correlação entre a concentração sérica e a expressão tecidual do fator de crescimento endotelial vascular (VEGF) na interface materno embrionária e avaliar a associação entre a profundidade da invasão trofoblástica e a expressão tecidual do VEGF em gestações ectópicas ampulares. Métodos: Estudo prospectivo com 34 mulheres com o diagnóstico de gestação ectópica ampular espontaneamente concebidas, submetidas à salpingectomia no período de 11 de julho de 2012 a 19 de agosto de 2013. Os critérios de exclusão foram: diagnóstico de gestação tubária não ampular, impossibilidade de coleta de sangue para a dosagem do VEGF sérico, da análise anatomopatológica ou da dosagem do VEGF na peça cirúrgica. Após a confirmação diagnóstica de gestação tubária e antes da realização da salpingectomia foram dosadas as concentrações séricas maternas de VEGF pela técnica de luminex. Após o procedimento cirúrgico foi analisada a expressão tecidual de VEGF por imuno-histoquímica e pela técnica de point-counting. Histologicamente, a invasão trofoblástica na parede tubária foi classificada em grau I: limitada à mucosa da tuba uterina; grau II: até a camada muscular; grau III: invasão de toda a espessura da tuba uterina. Resultados: 8 pacientes apresentaram invasão grau I, 7 pacientes com grau II e 19 com invasão grau III. Não se observou diferença estatisticamente significativa na associação entre o VEGF tecidual e os diferentes graus de invasão trofoblástica (p= 0,621) e a correlação do VEGF tecidual com a sua dosagem sérica pelo coeficiente de Spearman (Rho = -0,057) foi fraca (p= 0,748). Foi realizado modelo de regressão logística para comparar o desempenho do VEGF tecidual como fator de predição da profundidade da invasão do trofoblasto na parede tubária, comparando o grau I vs II e III e o grau III vs I e II e não houve diferença estatisticamente significativa. Conclusões: em gestações ectópicas ampulares, a profundidade da invasão do tecido trofoblástico na parede tubária não está associada com a concentração tecidual do VEGF e não há correlação entre as suas dosagens sérica e tecidual / Objetive: To evaluate the correlation between serum concentration and tissue expression of vascular endothelial growth factor (VEGF) at the feto-maternal interface and to associate the depth of trophoblastic invasion into the tubal wall with tissue VEGF in ampullary pregnancies. Methods: A prospective study was conducted on 34 spontaneously conceived ampullary ectopic pregnancies that were submitted to salpingectomy between July 11th, 2012 and August 19th, 2013. Exclusion criteria were: diagnosis of not ampullary pregnancy, impossibility of collecting blood sample for serum VEGF determination, impossibility of either anatomopathological or tissue VEGF analysis. Maternal serum VEGF concentrations were measured after the diagnosis confirmation and before salpingectomy. After surgery, tissue VEGF expression was measured by immunohistocemistry and point counting technique. Histologically, trophoblastic invasion into the tubal wall was classified as grade I when limited to the tubal mucosa, grade II when reaching the muscle layer and grade III when comprising the full thickness of the tubal wall. Results: 8 patients had tubal infiltration grade I, 7 had grade II and 19 had grade III infiltration. Depth of trophoblastic invasion was not associated with tissue VEGF expression (p= 0.621). The correlation between tissue expression and serum VEGF concentration was not present (Spearman\'s coefficient, Rho = -0.057) (p= 0.748). Logistic regression showed that tissue VEGF expression was not predictor of trophoblastic invasion and there was not statistically significant difference when comparing grade I vs II and III and grade III vs I and II. Conclusions: in ampullary pregnancies, the depth of trophoblastic penetration into the tubal wall is not associated with tissue VEGF expression. Serum VEGF do not show any correlation with tissue expression
52

Fator de crescimento endotelial vascular (VEGF): concentrações séricas e teciduais em gestações ectópicas ampulares e a profundidade da invasão trofoblástica / Vascular endothelial growth factor (VEGF): Serum and tissue concentration in ampular pregnancies and the depth of trophoblastic invasion

Teshima, Décio Roberto Kamio 11 November 2015 (has links)
Objetivo: Avaliar a correlação entre a concentração sérica e a expressão tecidual do fator de crescimento endotelial vascular (VEGF) na interface materno embrionária e avaliar a associação entre a profundidade da invasão trofoblástica e a expressão tecidual do VEGF em gestações ectópicas ampulares. Métodos: Estudo prospectivo com 34 mulheres com o diagnóstico de gestação ectópica ampular espontaneamente concebidas, submetidas à salpingectomia no período de 11 de julho de 2012 a 19 de agosto de 2013. Os critérios de exclusão foram: diagnóstico de gestação tubária não ampular, impossibilidade de coleta de sangue para a dosagem do VEGF sérico, da análise anatomopatológica ou da dosagem do VEGF na peça cirúrgica. Após a confirmação diagnóstica de gestação tubária e antes da realização da salpingectomia foram dosadas as concentrações séricas maternas de VEGF pela técnica de luminex. Após o procedimento cirúrgico foi analisada a expressão tecidual de VEGF por imuno-histoquímica e pela técnica de point-counting. Histologicamente, a invasão trofoblástica na parede tubária foi classificada em grau I: limitada à mucosa da tuba uterina; grau II: até a camada muscular; grau III: invasão de toda a espessura da tuba uterina. Resultados: 8 pacientes apresentaram invasão grau I, 7 pacientes com grau II e 19 com invasão grau III. Não se observou diferença estatisticamente significativa na associação entre o VEGF tecidual e os diferentes graus de invasão trofoblástica (p= 0,621) e a correlação do VEGF tecidual com a sua dosagem sérica pelo coeficiente de Spearman (Rho = -0,057) foi fraca (p= 0,748). Foi realizado modelo de regressão logística para comparar o desempenho do VEGF tecidual como fator de predição da profundidade da invasão do trofoblasto na parede tubária, comparando o grau I vs II e III e o grau III vs I e II e não houve diferença estatisticamente significativa. Conclusões: em gestações ectópicas ampulares, a profundidade da invasão do tecido trofoblástico na parede tubária não está associada com a concentração tecidual do VEGF e não há correlação entre as suas dosagens sérica e tecidual / Objetive: To evaluate the correlation between serum concentration and tissue expression of vascular endothelial growth factor (VEGF) at the feto-maternal interface and to associate the depth of trophoblastic invasion into the tubal wall with tissue VEGF in ampullary pregnancies. Methods: A prospective study was conducted on 34 spontaneously conceived ampullary ectopic pregnancies that were submitted to salpingectomy between July 11th, 2012 and August 19th, 2013. Exclusion criteria were: diagnosis of not ampullary pregnancy, impossibility of collecting blood sample for serum VEGF determination, impossibility of either anatomopathological or tissue VEGF analysis. Maternal serum VEGF concentrations were measured after the diagnosis confirmation and before salpingectomy. After surgery, tissue VEGF expression was measured by immunohistocemistry and point counting technique. Histologically, trophoblastic invasion into the tubal wall was classified as grade I when limited to the tubal mucosa, grade II when reaching the muscle layer and grade III when comprising the full thickness of the tubal wall. Results: 8 patients had tubal infiltration grade I, 7 had grade II and 19 had grade III infiltration. Depth of trophoblastic invasion was not associated with tissue VEGF expression (p= 0.621). The correlation between tissue expression and serum VEGF concentration was not present (Spearman\'s coefficient, Rho = -0.057) (p= 0.748). Logistic regression showed that tissue VEGF expression was not predictor of trophoblastic invasion and there was not statistically significant difference when comparing grade I vs II and III and grade III vs I and II. Conclusions: in ampullary pregnancies, the depth of trophoblastic penetration into the tubal wall is not associated with tissue VEGF expression. Serum VEGF do not show any correlation with tissue expression
53

The role of soluble FMS-like tyrosine-kinase-1, vascular endothelial growth factor and placental growth factor in HIV associated pre-eclamptic pregnancies : a South African perspective.

Govender, Nalini. January 2013 (has links)
Introduction and aims. South Africa is the epicenter of the HIV/AIDS pandemic. Hypertensive disorders of pregnancy (15.7%) are the second cause of maternal deaths of which pre-eclampsia represents 83%. Normal pregnancy requires a balance between pro- and anti-angiogenic factors to necessitate effective vasculogenesis, angiogenesis and placental development, however, pre-eclampsia is characterised by an excess anti-angiogenic state. The hypoxic placenta releases excess anti-angiogenic factors into the maternal circulation causing endothelial dysfunction. However, there is no data to verify if HIV infection affects pre-eclampsia, or if the angiogenic imbalance is affected. Contradictory data exists on the association between HIV infection and pre-eclampsia. In an attempt to assess the role of HIV infection in pre-eclampsia, this study examined the immunolocalisation of sFlt-1, sEng, PlGF and VEGF in placentae of HIV negative and positive normotensive and pre-eclamptic pregnancies at term using immunohistochemistry (IHC) and immunoelectron microscopy (IEM). Additionally, we estimated the placental expression of sFlt-1, sEng, PlGF and VEGF to verify if the HIV negative differed from the HIV positive cohorts. We further evaluated the maternal serum to determine if variations existed in the circulating levels of these factors in HIV negative and positive normotensive and pre-eclamptic pregnancies. Methods. Following institutional ethical approval and informed consent, placental biopsies and maternal serum were collected post-delivery. For IHC and IEM, 130 and 25 placentae were evaluated, respectively. Following conventional immunohistochemical processing, 5μm sections were immunostained & immunoexpression of the various antibodies were evaluated with the Zeiss Axioscope A1 interfaced with an AxioVision Image analysis software package (version 4.8.3) in combination with the auto-measurement module (Carl Zeiss, Germany). Post-conventional immunoelectron processing, ultra-thin sections were immunolabelled. Sections were post-fixed, contrast enhanced with uranyl acetate and Reynolds lead citrate and viewed on a Jeol 1011 Transmission Electron Microscope. Additionally, the placental expressions of these factors were assessed using RT-PCR. In an attempt to confirm if maternal circulating levels of these factors differed, we quantitatively evaluated these factors in serum from HIV negative normotensives, HIV negative pre-eclamptics, HIV positive normotensives, and HIV positive pre-eclamptics using ELISA techniques. Results and Discussion. The expression of sFlt-1, sEng, PlGF and VEGF was confirmed using immunohistochemistry, RT-PCR and ELISAs. Irrespective of the HIV status, sFlt-1 and sEng was elevated with the concomitant reduction in PlGF in pre-eclamptic compared to normotensive pregnancies. The levels of VEGF were however undetectable across all study groups. It is plausible that this lack of effect of HIV status on the factors under study may be attributed to the treatment regimen as HAART is known to restore the immune response of HIV positive preeclamptic women. However, a concise anti-retroviral treatment history in our study was unavailable. Additionally, this study is novel in that it ultrastructurally immunolocalises sFlt-1, sEng, PlGF and VEGF within the placenta. This immunoelectron localisation data corresponds to our immunohistochemical data. Our study further demonstrates strong immunoreactivity of both placental sFlt-1 and sEng in pre-eclampsia with concurrent elevations in the maternal circulation. A qualitative increase in the occurrence of syncytial knots in the pre-eclamptics compared to the normotensive pregnancies was noted. These observations support the detachment of antixxx angiogenic rich microparticles from syncytial knots in the pre-eclamptics compared to the normotensive pregnancies was noted. These observations support the detachment of antiangiogenic rich microparticles from syncytial knots and their subsequent deportation and elevation in the maternal circulation. Moreover, their consequent antagonistic effects on VEGF, PlGF and TGF-β, disrupts the vascular endothelial maintenance. The strong immunoreactivity of sFlt-1, sEng, PlGF and VEGF was observed in villous endothelial cells. Moreover, a strong sFlt-1 and sEng but a weak PlGF and VEGF immunoreactivity was noted in syncytio- and cytotrophoblasts. This immunoexpression within trophoblasts is suggestive of their autocrine mode of action on normal trophoblast functions including invasion, differentiation and production. It is plausible that the angiogenic imbalance observed in our study, will impact on placental function, by modifying trophoblast activity thereby contributing to abnormal placentation. Conclusion. Our study supports the hypothesis that pre-eclampsia is characterized by an imbalance between pro- and anti-angiogenic factors. Whether the pregnancy is complicated by immune insufficiencies or not, does not affect the role of the anti-angiogenic factors in pre-eclampsia development. Nevertheless, the neutralising effect of HIV infection on the immune system may be insufficient in the development of pre-eclampsia. To our knowledge, the quantification of serum pro-/anti-angiogenic factors in HIV-associated pre-eclampsia is novel. In conclusion, our data reinforces the hypothesis that increased concentrations of sFlt-1 and sEng are involved in the pathogenesis of pre-eclampsia and indicates their possible use as discriminatory factors between diseases. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2013.
54

Identification and characterization of novel secreted factors involved in bone remodeling

Chim, Shek Man January 2009 (has links)
[Truncated abstract] Bone remodeling is an important process to maintain mechanical integrity. It is accomplished by two important steps, bone resorption followed by new bone formation. Osteoclasts and osteoblasts are the principal cells in bone resorption and bone formation, respectively. A multitude of local and systemic factors regulates this process by controlling the cellular activities in bone remodeling compartments (BRC). An imbalance of osteoblastic bone formation and osteoclastic bone destruction will result in the development of skeletal diseases. Recent studies suggested that angiogenesis is closely associated with bone remodeling. The vasculature in bone is important for skeletal development, growth and repair. During endochondral ossification, cartilage is invaded by blood vessels which bring in osteoblast and osteoclast precursor cells, nutrients, growth factors and differentiation factors. During fracture repair, it has been demonstrated that mature osteoclasts produce heparanase which can degrade heparin sulfate proteoglycans, a major component in extracellular matrix (ECM). The process leads to the release of heparin-binding growth factors including vascular endothelial growth factor (VEGF), a potent angiogenic factor which contributes largely to local angiogenesis. In recent studies, endothelial cells have been found to produce bone morphogenetic protein (BMP)-2 and BMP-4 when they are subjected to mechanical stimuli, or a hypoxia environment. Conversely, inhibition of angiogenesis has been shown to prevent fracture healing. In a distraction osteogenesis model, either inhibition of angiogenesis or disruption of the mechanical environment prevents normal osteogenesis and results in fibrous nonunion. .... A total of 42 mice from F1 and F2 generations were genotyped as transgene positive. Preliminary analysis using radiography did not reveal any difference between the gross structures of transgenic and wild type mice. Interestingly, the preliminary histology revealed a decrease in trabecular bone and an increase of lipid space in metaphysis of transgenic mice overexpressing EGFL6. However, further studies will need to be carried out to investigate the role of EGFL6 in angiogenesis and adipogenesis using a transgenic mice model. This will be a prime focus of future work. Collectively, the results presented in this thesis have identified EGFL6, a member of the EGF-like family, as a potential angiogenic factor which may play an important role in bone remodeling. EGFL6 has been found to be expressed highly in calvarial osteoblasts and upregulated during primary murine osteoblast differentiation. EGFL6 has been 8 characterized to be a secreted homomeric complex. More importantly, EGFL6 has been shown to induce angiogenic activity in endothelial cell migration, tube formation and in vivo chick embryo chorioallantoic membrane assay. Furthermore, conditioned medium containing the EGFL6 recombinant protein was shown to induce phosphorylation of ERK in endothelial cells. Inhibition of ERK impaired EGFL6-induced ERK activation and endothelial cell migration. Taken together these studies raise the possibility that EGFL6 has a potential role in angiogenesis, and mediates a paracrine mechanism of cross-talk between vascular endothelial cells and osteoblasts during osteogenesis. An understanding of this process offers the potential to facilitate the development of therapeutic treatments for bone disease.
55

Deneysel hidronefrozda nitrik oksit ve vasküler endotelyal growth faktörü arasındaki bağıntı /

Kaya, Ş. Abdullah. Savaş, Mustafa. Çağrı. January 2006 (has links) (PDF)
Tez (Tıpta Uzmanlık) - Süleyman Demirel Üniversitesi, Tıp Fakültesi, Çocuk Cerrahisi Anabilim Dalı, 2006. / Kaynakça var.
56

From gene mutation to gene expression : studies on multiple endocrine neoplasia type 1 and vascular endothelial growth factors /

Tham, Emma, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
57

Reactive species promotion of head and neck squamous cell carcinoma

Bradburn, Jennifer Elizabeth, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 161-184).
58

Fator de crescimento do endotélio vascular na viabilidade do retalho musculofasciocutâneo transverso do reto do abdome, em ratos submetidos à nicotina / Vascular endothelial growth factor in the viability of transverse rectus abdominis musculofasciocutaneous, in rats submitted to nicotine

Silveira, Tiago Santos [UNIFESP] 30 July 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Introdução: Diversos fatores podem diminuir a viabilidade do retalho TRAM, dentre eles a nicotina que tem sido responsabilizada pela perda parcial ou total destes retalhos. Objetivo: Avaliar a ação do Fator de Crescimento do Endotélio Vascular na viabilidade do Retalho Musculofasciocutâneo Transverso do Reto do Abdome, em ratos submetidos à nicotina. Métodos: Foram utilizados 60 Ratos Wistar EPM-1, machos adultos, pesando de 230 a 300g, aleatorizados em 4 grupos de 15 animais cada: Grupo Controle composto por animais que foram submetidos ao retalho TRAM; Grupo Nicotina composto por animais que foram submetidos á nicotina e ao retalho TRAM; Grupo VEGF composto por animais submetidos à administração de VEGF plasmidial antes do retalho TRAM; e Grupo Nicotina+VEGF composto por animais que foram submetidos à nicotina, tratados com administração de VEGF e submetidos ao retalho TRAM. Para análise dos resultados foi realizado método de análise da área de necrose e de densidade vascular. Resultados: Houve diferença estatisticamente significativa na comparação entre todos os grupos, com relação às variáveis área de necrose e densidade vascular (p<0,05). Os animais do Grupo VEGF apresentaram a menor área de necrose (4.10%) e a maior densidade vascular (39%) em relação aos outros grupos do estudo. Conclusão: O Fator de Crescimento do Endotélio Vascular aumentou a viabilidade do retalho musculofasciocutâneo transverso do reto do abdome, em ratos submetidos à nicotina. / Introduction: Several factors can reduce the viability of the TRAM flap, among them the nicotine has been made responsible by the loss partial or total of these flaps. Objective: To evaluate the action of the Vascular endothelial Growth Factor in the viability of the Transverse Rectus Abdominis Musculocutaneous, in rats submitted to the nicotine. Methods: Sixty Wistar EPM-1 rats were used, adult males, weighing from 230 to 300g, randomized in 4 groups of 15 animals each: Group Control composed by animals that were submitted to the TRAM flap; Group Nicotine composed by animals that were nicotine exposed and submitted of TRAM flap; Group VEGF composed by animals submitted to the administration of VEGF plasmidial before the TRAM flap; and Group Nicotina+VEGF composed by animals that were exposed to the nicotine, trated with administration of VEGF and submitted to the TRAM flap. For analysis of the results they were done necrosis area and vascular density. Results: There was estatistic significant differentiates in the comparison among all of the groups, regarding the variables necrosis area and vascular density (p <0,05). Conclusion: The Vascular Endothelial Growth Factor increased the viability of the Transverse Rectus Abdominis Musculocutaneous, in rats submitted to the nicotine. / TEDE / BV UNIFESP: Teses e dissertações
59

Dosagem seriada dos fatores reguladores de angiogênese soluble fms-like tyrosine kinase-1 (sFlt-1) e placental growth factor (PIGF) para predição de pré-eclâmpsia e pré-eclâmpsia superajuntada / Serial assessment of the angiogenic factors soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) levels for predicting preeclampsia and superimposed preeclampsia

Rafaela Alkmin da Costa 22 October 2014 (has links)
Apesar de sua importância clínica e epidemiológica, a fisiopatologia da préeclâmpsia ainda não foi completamente compreendida. Sabe-se que a doença constitui-se de uma fase pré-clínica e um estágio clínico. Durante a última década muito esforço tem se concentrado na identificação precoce da doença, ainda em sua fase pré-clínica. A literatura científica tem demonstrado claramente um desequilíbrio na regulação da angiogênese das gestantes com pré-eclâmpsia, marcado por níveis elevados do fator antiangiogênico soluble fms-like tyrosine kinase-1 (sFlt-1) e níveis diminuídos do fator pró-angiogênico placental growth fator (PlGF). Embora um número crescente de estudos em populações de alto risco tenha avaliado o papel desses biomarcadores no diagnóstico de pré-eclâmpsia, dados sobre sua utilização para a predição de pré-eclâmpsia superajuntada, cujo diagnóstico pode ser particularmente difícil, permanecem relativamente escassos e controversos. Com o presente estudo pretendemos avaliar o desempenho de medidas seriadas dos níveis maternos circulantes dos fatores sFlt-1 e PlGF, bem como da razão sFlt-1/PlGF, para predição de pré-eclâmpsia superajuntada e compará-lo ao seu desempenho na predição de pré-eclâmpsia em sua forma \"pura\", não superajuntada. Para este propósito, estudamos uma coorte prospectiva composta de dois braços, um de gestantes com hipertensão arterial crônica e outro de gestantes normotensas, e avaliamos os níveis séricos de sFlt-1 e de PlGF e a razão sFlt-1/PlGF nas idades gestacionais de 20, 26, 32 e 36 semanas, tendo como desfecho principal o diagnóstico de pré-eclâmpsia. Um total de 97 gestantes foram acompanhadas, 37 normotensas e 60 com hipertensão arterial crônica. Entre elas, 4 (10,8%) desenvolveram pré-eclâmpsia e 14 (23,3%) desenvolveram pré-eclâmpsia superajuntada. Para predição de pré-eclâmpsia, a análise ROC (Receiver Operating Characteristics) apresentou área sob a curva (AUC - area under curve) de 0,83 (IC 95% = 0,68-0,99, P = 0,035) para dosagem de PlGF com 20 semanas e AUC = 0,92 (IC 95% = 0,81 - 1,00, P = 0,007) para a razão sFlt-1/PlGF com 26 semanas de gestação. A variação percentual dos níveis de PlGF entre 26 e 32 semanas de gestação apresentou AUC = 0,96 (IC de 95% = 0,89-1,00, P = 0,003). Para a predição de pré-eclâmpsia superajuntada, a razão sFlt-1/PIGF na idade gestacional de 32 semanas apresentou AUC = 0,69 (IC de 95% = 0,53-0,85, P = 0,039). Entre 20 e 26 semanas de gestação, a variação percentual do PIGF e da razão sFlt-1/PlGF apresentaram, respectivamente, AUC = 0,74 (IC de 95% = 0,58-0,90, P = 0,018) e AUC = 0,71 (IC 95% = 0,52-0,91, P = 0,034). Por nossos resultados podemos concluir que, embora os níveis de PlGF e a razão sFlt-1/ PlGF tenham apresentado bons desempenhos na predição de pré-eclâmpsia, é preciso ter cuidado ao usá-los para a predição de pré-eclâmpsia superajuntada. Nessas gestantes, a dosagem dos fatores angiogênicos apresenta capacidade de predição menor e mais tardia. Avaliações seriadas dos fatores podem melhorar o desempenho dos testes para predição de pré-eclâmpsia superajuntada em idades gestacionais mais precoces / Despite being a major public health problem, the pathophysiology of preeclampsia is incompletely understood. Preeclampsia progression comprises a pre-clinical stage and a clinical stage. During the last decade much work has focused on identifying the pre-clinical stage of preeclampsia. Many researchers have clearly demonstrated an anti-angiogenic imbalance that is marked by higher levels of soluble fms-like tyrosine kinase-1 (sFlt-1) and lower levels of placental growth factor (PlGF) in the subjects who develop preeclampsia compared with those who do not. Although a growing number of studies in the high-risk population have shown the role of these biomarkers in diagnosing preeclampsia, superimposed preeclampsia, which can be a challenging diagnosis, remains partially understudied and the literature regarding this subject continues to be relatively scarce as well as controversial. By this study, we aimed to evaluate the performance of serial measurements of maternal circulating sFlt-1 and PlGF levels for the prediction of superimposed preeclampsia in chronic hypertensive subjects and to compare it to the prediction of preeclampsia in normotensive control subjects. For this purpose, we evaluated a two-armed prospective cohort of women with normotensive and chronic hypertensive pregnancies and assessed the serum levels of sFlt-1 and PlGF and the sFlt-1/PlGF ratio at gestational ages of 20, 26, 32 and 36 weeks, having preeclampsia as the primary outcome to be predicted. A total of 97 women were followed-up, 37 in the normotensive group and 60 in the chronic hypertensive group. Among them, 4 (10.8%) women developed preeclampsia and 14 (23.3%) developed superimposed preeclampsia. For predicting preeclampsia, PlGF at 20 gestational weeks presented an AUC=0.83 (CI 95% = 0.68 - 0.99, P=0.035) and the sFlt-1/PlGF ratio at 26 gestational weeks presented an AUC=0.92 (CI95% = 0.81 - 1.00, P=0.007). The percent change of the PlGF levels between 26 and 32 gestational weeks presented an AUC=0.96 (CI 95% = 0.89 - 1.00, P=0.003). For predicting superimposed preeclampsia, the sFlt-1/PlGF ratio at 32 gestational weeks presented an AUC=0.69 (CI 95% = 0.53 - 0.85, P=0.039). Between 20 and 26 gestational weeks, the percent change of PlGF and the sFlt-1/PlGF ratio presented, respectively, an AUC=0.74 (CI 95% = 0.58 - 0.90, P=0.018) and an AUC=0.71 (CI 95% = 0.52 - 0.91, P=0.034). By our results, we concluded that, although the PlGF level and the sFlt-1/PlGF ratio present good performances in the prediction of preeclampsia, caution is required when using them for the prediction of superimposed preeclampsia. Sequential assessments slightly improve the test performances for predicting superimposed preeclampsia at earlier gestational ages
60

Angiogenic gene signature in human pancreatic cancer correlates with TGF-beta and inflammatory transcriptomes

Craven, Kelly E. 11 April 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Pancreatic ductal adenocarcinoma (PDAC), which comprises 85% of pancreatic cancers, is the 4th leading cause of cancer death in the United States with a 5-year survival rate of 8%. While human PDACs (hPDACs) are hypovascular, they also overexpress a number of angiogenic growth factors and receptors. Additionally, the use of anti-angiogenic agents in murine models of PDAC leads to reduced tumor volume, tumor spread, and microvessel density (MVD), and improved survival. Nonetheless, clinical trials using anti-angiogenic therapy have been overwhelmingly unsuccessful in hPDAC. On the other hand, pancreatic neuroendocrine tumors (PNETs) account for only 2% of pancreatic tumors, yet they are very vascular and classically angiogenic, respond to anti-angiogenic therapy, and confer a better prognosis than PDAC even in the metastatic setting. In an effort to compare and contrast the angiogenic transcriptomes of these two tumor types, we analyzed RNA-Sequencing (RNA-Seq) data from The Cancer Genome Atlas (TCGA) and found that a pro-angiogenic gene signature is present in 35% of PDACs and that it is mostly distinct from the angiogenic signature present in PNETs. The pro-angiogenic PDAC subgroup also exhibits a transcriptome that reflects active TGF-β signaling, less frequent SMAD4 inactivation than PDACs without the signature, and up-regulation of several pro-inflammatory genes, including members of JAK signaling pathways. Consequently, targeting the TGF-β receptor type-1 kinase with SB505124 and JAK1/2 with ruxolitinib blocks proliferative crosstalk between human pancreatic cancer cells (PCCs) and human endothelial cells (ECs). Additionally, treatment of the KRC (oncogenic Kras, homozygous deletion of Rb1) and KPC (oncogenic Kras, mutated Trp53) genetically engineered PDAC mouse models with ruxolitinib suppresses murine PDAC (mPDAC) progression only in the KRC model, which shows superior enrichment and differential expression of the human pro-angiogenic gene signature as compared to KPC tumors. These findings suggest that targeting both TGF-β and JAK signaling in the 35% of PDAC patients whose cancers exhibit an pro-angiogenic gene signature should be explored in a clinical trial.

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