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Sample records for chagasic human syncytiotrophoblast

  1. Atypical Cristae Morphology of Human Syncytiotrophoblast Mitochondria

    PubMed Central

    De Los Rios Castillo, Daniela; Zarco-Zavala, Mariel; Olvera-Sanchez, Sofia; Pardo, Juan Pablo; Juarez, Oscar; Martinez, Federico; Mendoza-Hernandez, Guillermo; García-Trejo, José J.; Flores-Herrera, Oscar

    2011-01-01

    Mitochondrial complexes I, III2, and IV from human cytotrophoblast and syncytiotrophoblast associate to form supercomplexes or respirasomes, with the following stoichiometries: I1:(III2)1 and I1:(III2)1–2:IV1–4. The content of respirasomes was similar in both cell types after isolating mitochondria. However, syncytiotrophoblast mitochondria possess low levels of dimeric complex V and do not have orthodox cristae morphology. In contrast, cytotrophoblast mitochondria show normal cristae morphology and a higher content of ATP synthase dimer. Consistent with the dimerizing role of the ATPase inhibitory protein (IF1) (García, J. J., Morales-Ríos, E., Cortés-Hernandez, P., and Rodríguez-Zavala, J. S. (2006) Biochemistry 45, 12695–12703), higher relative amounts of IF1 were observed in cytotrophoblast when compared with syncytiotrophoblast mitochondria. Therefore, there is a correlation between dimerization of complex V, IF1 expression, and the morphology of mitochondrial cristae in human placental mitochondria. The possible relationship between cristae architecture and the physiological function of the syncytiotrophoblast mitochondria is discussed. PMID:21572045

  2. Punicalagin promotes autophagy to protect primary human syncytiotrophoblasts from apoptosis.

    PubMed

    Wang, Ying; Chen, Baosheng; Longtine, Mark S; Nelson, D Michael

    2016-02-01

    Punicalagin is a prominent polyphenol in pomegranate juice that protects cultured syncytiotrophoblasts from stress-induced apoptosis. Here, we test the hypothesis that punicalagin has this effect by inhibiting the mTOR kinase pathway to enhance autophagic turnover and limit apoptosis in cultured primary human syncytiotrophoblasts. In syncytiotrophoblasts, starvation, rapamycin, or punicalagin all decreased the expression of phosphorylated ribosomal protein S6, a downstream target of the mTOR kinase, and of the autophagy markers, LC3-II and p62. In contrast, in the presence of bafilomycin, an inhibitor of late stages of autophagy and degradation in the autophagolysosome, syncytiotrophoblasts exposed to starvation, rapamycin, or punicalagin all showed increased levels of LC3-II and p62. The number of LC3-II punctae also increased in punicalagin-treated syncytiotrophoblasts exposed to chloroquine, another inhibitor of autophagic degradation, and punicalagin increased the number of lysosomes. The apoptosis-reducing effect of punicalagin was attenuated by inhibition of autophagy using bafilomycin or knockdown of the autophagy related gene, ATG16L1. Collectively, these data support the hypothesis that punicalagin modulates the crosstalk between autophagy and apoptosis to promote survival in cultured syncytiotrophoblasts. PMID:26659860

  3. Studies of the dynamics of nuclear clustering in human syncytiotrophoblast.

    PubMed

    Calvert, S J; Longtine, M S; Cotter, S; Jones, C J P; Sibley, C P; Aplin, J D; Nelson, D M; Heazell, A E P

    2016-06-01

    Syncytial nuclear aggregates (SNAs), clusters of nuclei in the syncytiotrophoblast of the human placenta, are increased as gestation advances and in pregnancy pathologies. The origins of increased SNAs are unclear; however, a better appreciation of the mechanism may give insight into placental ageing and factors underpinning dysfunction. We developed three models to investigate whether SNA formation results from a dynamic process of nuclear movement and to generate alternative hypotheses. SNA count and size were measured in placental explants cultured over 16 days and particles released into culture medium were quantified. Primary trophoblasts were cultured for 6 days. Explants and trophoblasts were cultured with and without cytoskeletal inhibitors. An in silico model was developed to examine the effects of modulating nuclear behaviour on clustering. In explants, neither median SNA number (108 SNA/mm(2) villous area) nor size (283 μm(2)) changed over time. Subcellular particles from conditioned culture medium showed a wide range of sizes that overlapped with those of SNAs. Nuclei in primary trophoblasts did not change position relative to other nuclei; apparent movement was associated with positional changes of the syncytial cell membrane. In both models, SNAs and nuclear clusters were stable despite pharmacological disruption of cytoskeletal activity. In silico, increased nuclear movement, adhesiveness and sites of cytotrophoblast fusion were related to nuclear clustering. The prominence of SNAs in pregnancy disorders may not result from an active process involving cytoskeleton-mediated rearrangement of syncytial nuclei. Further insights into the mechanism(s) of SNA formation will aid understanding of their increased presence in pregnancy pathologies. PMID:27002000

  4. A correlative review of acetylcholine synthesis in relation to histopathology of the human syncytiotrophoblast.

    PubMed

    Satyanarayana, M

    1986-01-01

    Acetylcholine (ACh) is localized in the syncytiotrophoblast layer of the human placental villous tissue. An attempt was made to correlate the ACh synthesis in different pathological placentas with the histopathology of the syncytiotrophoblast available in the literature. The ACh synthesis was estimated by 'in vitro' incubation of the placental tissue. Full-term (36-38 weeks) vaginally delivered pathological placentas and hydatid moles (28 weeks) were compared with normal placentas of the same age. The results suggested that: ACh synthesis is normal in states with normal syncytiotrophoblast (e.g., healthy greater than 42 week placenta, placenta praevia, twins, and hydramnios); high ACh synthesis is correlated with hormonal and immunological changes (e.g., diabetes mellitus and Rh-incompatibility); low levels of ACh synthesis occur in states with moderate syncytial degeneration (e.g., nephrotic syndrome and essential hypertension); very poor ACh synthesis occurs when syncytial degeneration is advanced (e.g., preeclampsia, eclampsia, intra-uterine death of fetus, vesicles of hydatid mole and placental tissue infarcts); and ACh synthesis is nil in material that is completely devoid of syncytiotrophoblast (e.g., placental tissue-like material, which rarely appears in between the vesicles of hydatid moles). In essence, the degree of reduction in ACh synthesis seems to correlate with the state of the syncytiotrophoblast in various pathological conditions; and ACh synthesis is greatly reduced during syncytial degeneration. It is concluded that the capacity of the placenta to synthesize ACh reflects the state of the syncytiotrophoblast. PMID:3799152

  5. The interleukin 2 gene is expressed in the syncytiotrophoblast of the human placenta

    SciTech Connect

    Boehm, K.D.; Kelley, M.F.; Ilan, J.; Ilan, J. )

    1989-01-01

    The lymphokine interleukin 2 is an important immune system regulatory glycopolypeptide. It is produced by antigen- or mitogen-stimulated T lymphocytes and is required for the proliferation or clonal expansion of activated T lymphocytes. In this report, it is demonstrated by RNA transfer blot hybridization that the poly(A){sup +} RNA population of the human placenta contains a 0.85-kilobase RNA transcript that specifically hybridizes to a human interleukin 2 cDNA probe. By using hybridization histochemistry in situ, it is further shown that interleukin 2 RNA transcripts are localized, primarily, to the syncytial (syncytiotrophoblast) layer of the human placenta. Possible roles for syncytiotrophoblast-produced interleukin 2 are suggested and discussed.

  6. Hypoxia downregulates p53 but induces apoptosis and enhances expression of BAD in cultures of human syncytiotrophoblasts.

    PubMed

    Chen, Baosheng; Longtine, Mark S; Sadovsky, Yoel; Nelson, D Michael

    2010-11-01

    Hypoxia is commonly assigned a role in the placental dysfunction characteristic of preeclampsia and intrauterine growth restriction. We previously showed that hypoxia upregulates p53 and enhances apoptosis in primary cultures of human cytotrophoblasts. Here we tested the hypothesis that hypoxia also induces apoptosis in syncytiotrophoblasts by upregulation of p53. Primary cultures of human cytotrophoblasts that had differentiated into syncytiotrophoblasts by 52 h were exposed for ≤24 h to 20% or <1% oxygen in the presence or absence of staurosporine or the p53 modulators nutlin-3, pifithrin-α, and pifithrin-μ. Proteins were detected by Western blot analysis or immunofluorescence. Compared with 20% oxygen, exposure of syncytiotrophoblasts to <1% oxygen upregulated hypoxia-inducible factor (HIF)-1α and rapidly downregulated p53. Activity of p53 in hypoxic syncytiotrophoblasts was reduced by the higher expression of the negative p53 regulator MDMX and by the reduction of phosphorylation of p53 at Ser(392), which reduces p53 activity. Conversely, staurosporine, a kinase inhibitor, and nutlin-3, a drug that enhances p53 expression, both raised p53 levels and increased the rate of apoptosis in syncytiotrophoblasts compared with vehicle controls. Immunofluorescence staining showed p53 immunolocalized to both cytoplasm and nuclei of nutlin-3-exposed syncytiotrophoblasts. The hypoxia-induced apoptosis in syncytiotrophoblasts correlated with enhanced expression of the proapoptotic BAD and a reduced level of antiapoptotic BAD phosphorylated on Ser(112). We surmise that cell death induced by extreme hypoxia in syncytiotrophoblasts follows a non-p53-dependent pathway, unlike that of a nonhypoxic stimulus and unlike hypoxic cytotrophoblasts. We speculate that downregulation of p53 activity in response to hypoxia reduces or eliminates the apoptosis transduced by the p53 pathway in syncytiotrophoblasts, thereby limiting cell death and maintaining the integrity of this

  7. Hypoxia downregulates p53 but induces apoptosis and enhances expression of BAD in cultures of human syncytiotrophoblasts

    PubMed Central

    Chen, Baosheng; Longtine, Mark S.; Sadovsky, Yoel

    2010-01-01

    Hypoxia is commonly assigned a role in the placental dysfunction characteristic of preeclampsia and intrauterine growth restriction. We previously showed that hypoxia upregulates p53 and enhances apoptosis in primary cultures of human cytotrophoblasts. Here we tested the hypothesis that hypoxia also induces apoptosis in syncytiotrophoblasts by upregulation of p53. Primary cultures of human cytotrophoblasts that had differentiated into syncytiotrophoblasts by 52 h were exposed for ≤24 h to 20% or <1% oxygen in the presence or absence of staurosporine or the p53 modulators nutlin-3, pifithrin-α, and pifithrin-μ. Proteins were detected by Western blot analysis or immunofluorescence. Compared with 20% oxygen, exposure of syncytiotrophoblasts to <1% oxygen upregulated hypoxia-inducible factor (HIF)-1α and rapidly downregulated p53. Activity of p53 in hypoxic syncytiotrophoblasts was reduced by the higher expression of the negative p53 regulator MDMX and by the reduction of phosphorylation of p53 at Ser392, which reduces p53 activity. Conversely, staurosporine, a kinase inhibitor, and nutlin-3, a drug that enhances p53 expression, both raised p53 levels and increased the rate of apoptosis in syncytiotrophoblasts compared with vehicle controls. Immunofluorescence staining showed p53 immunolocalized to both cytoplasm and nuclei of nutlin-3-exposed syncytiotrophoblasts. The hypoxia-induced apoptosis in syncytiotrophoblasts correlated with enhanced expression of the proapoptotic BAD and a reduced level of antiapoptotic BAD phosphorylated on Ser112. We surmise that cell death induced by extreme hypoxia in syncytiotrophoblasts follows a non-p53-dependent pathway, unlike that of a nonhypoxic stimulus and unlike hypoxic cytotrophoblasts. We speculate that downregulation of p53 activity in response to hypoxia reduces or eliminates the apoptosis transduced by the p53 pathway in syncytiotrophoblasts, thereby limiting cell death and maintaining the integrity of this critical

  8. Comparison of syncytiotrophoblast generated from human embryonic stem cells and from term placentas

    PubMed Central

    Yabe, Shinichiro; Alexenko, Andrei P.; Amita, Mitsuyoshi; Yang, Ying; Schust, Danny J.; Ezashi, Toshihiko; Roberts, R. Michael

    2016-01-01

    Human embryonic stem cells (ESCs) readily commit to the trophoblast lineage after exposure to bone morphogenetic protein-4 (BMP-4) and two small compounds, an activin A signaling inhibitor and a FGF2 signaling inhibitor (BMP4/A83-01/PD173074; BAP treatment). During differentiation, areas emerge within the colonies with the biochemical and morphological features of syncytiotrophoblast (STB). Relatively pure fractions of mononucleated cytotrophoblast (CTB) and larger syncytial sheets displaying the expected markers of STB can be obtained by differential filtration of dispersed colonies through nylon strainers. RNA-seq analysis of these fractions has allowed them to be compared with cytotrophoblasts isolated from term placentas before and after such cells had formed syncytia. Although it is clear from extensive gene marker analysis that both ESC- and placenta-derived syncytial cells are trophoblast, each with the potential to transport a wide range of solutes and synthesize placental hormones, their transcriptome profiles are sufficiently dissimilar to suggest that the two cell types have distinct pedigrees and represent functionally different kinds of STB. We propose that the STB generated from human ESCs represents the primitive syncytium encountered in early pregnancy soon after the human trophoblast invades into the uterine wall. PMID:27051068

  9. Comparison of syncytiotrophoblast generated from human embryonic stem cells and from term placentas.

    PubMed

    Yabe, Shinichiro; Alexenko, Andrei P; Amita, Mitsuyoshi; Yang, Ying; Schust, Danny J; Sadovsky, Yoel; Ezashi, Toshihiko; Roberts, R Michael

    2016-05-10

    Human embryonic stem cells (ESCs) readily commit to the trophoblast lineage after exposure to bone morphogenetic protein-4 (BMP-4) and two small compounds, an activin A signaling inhibitor and a FGF2 signaling inhibitor (BMP4/A83-01/PD173074; BAP treatment). During differentiation, areas emerge within the colonies with the biochemical and morphological features of syncytiotrophoblast (STB). Relatively pure fractions of mononucleated cytotrophoblast (CTB) and larger syncytial sheets displaying the expected markers of STB can be obtained by differential filtration of dispersed colonies through nylon strainers. RNA-seq analysis of these fractions has allowed them to be compared with cytotrophoblasts isolated from term placentas before and after such cells had formed syncytia. Although it is clear from extensive gene marker analysis that both ESC- and placenta-derived syncytial cells are trophoblast, each with the potential to transport a wide range of solutes and synthesize placental hormones, their transcriptome profiles are sufficiently dissimilar to suggest that the two cell types have distinct pedigrees and represent functionally different kinds of STB. We propose that the STB generated from human ESCs represents the primitive syncytium encountered in early pregnancy soon after the human trophoblast invades into the uterine wall. PMID:27051068

  10. The endocannabinoid 2-arachidonoylglycerol dysregulates the synthesis of proteins by the human syncytiotrophoblast.

    PubMed

    Costa, M A; Fonseca, B M; Mendes, A; Braga, J; Teixeira, N A; Correia-da-Silva, G

    2016-03-01

    In recent years, endocannabinoids emerged as new players in various reproductive events. Recently, we demonstrated the involvement of 2-arachidonoylglycerol (2-AG) in human cytotrophoblast apoptosis and syncytialization. However, 2-AG impact in hormone production by the syncytiotrophoblast (hST) was never studied. In this work, we demonstrate that 2-AG activates cannabinoid (CB) receptors, exerting an inhibitory action on cyclic AMP/protein kinase A (cAMP/PKA) and mitogen-activated protein kinase (MAPK) p38 pathways, and enhancing ERK 1/2 phosphorylation. Furthermore, 2-AG affects the synthesis of human chorionic gonadotropin (hCG), leptin, aromatase, 3-β-hydroxysteroid dehydrogenase (3-β-HSD), and placental protein 13 (PP13). These 2-AG effects are mediated by the activation of CB receptors, in a mechanism that may involve p38, ERK 1/2 and cAMP/PKA pathways, which participate in the regulation of placental proteins expression. To our knowledge, this is the first study that associates the endocannabinoid signalling and endocrine placental function, shedding light on a role for 2-AG in the complex network of molecules that orchestrate the production of placental proteins essential for the gestational success. PMID:26698196

  11. Transcriptomic signatures of villous cytotrophoblast and syncytiotrophoblast in term human placenta.

    PubMed

    Rouault, Christine; Clément, Karine; Guesnon, Mickael; Henegar, Corneliu; Charles, Marie-Aline; Heude, Barbara; Evain-Brion, Danièle; Degrelle, Séverine A; Fournier, Thierry

    2016-08-01

    During pregnancy, the placenta ensures multiple functions, which are directly involved in the initiation, fetal growth and outcome of gestation. The placental tissue involved in maternal-fetal exchanges and in synthesis of pregnancy hormones is the mononucleated villous cytotrophoblast (VCT) which aggregates and fuses to form and renew the syncytiotrophoblast (ST). Knowledge of the gene expression pattern specific to this endocrine and exchanges tissue of human placenta is of major importance to understand functions of this heterogeneous and complex tissue. Therefore, we undertook a global analysis of the gene expression profiles of primary cultured-VCT (n = 6) and in vitro-differentiated-ST (n = 5) in comparison with whole term placental tissue from which mononucleated VCT were isolated. A total of 880 differentially expressed genes (DEG) were observed between VCT/ST compared to whole placenta, and a total of 37 and 137 genes were significantly up and down-regulated, respectively, in VCT compared to ST. The 37 VCT-genes were involved in cellular processes (assembly, organization, and maintenance), whereas the 137 ST-genes were associated with lipid metabolism and cell morphology. In silico, all networks were linked to 3 transcriptional regulators (PPARγ, RARα and NR2F1) which are known to be essential for trophoblast differentiation. A subset of six DEG was validated by RT-qPCR and four by immunohistochemistry. To conclude, recognition of these pathways is fundamental to increase our understanding of the molecular basis of human trophoblast differentiation. The present study provides for the first time a gene expression signature of the VCT and ST compared to their originated term human placental tissue. PMID:27452442

  12. Cytoadherence of Plasmodium falciparum to intercellular adhesion molecule 1 and chondroitin-4-sulfate expressed by the syncytiotrophoblast in the human placenta.

    PubMed Central

    Maubert, B; Guilbert, L J; Deloron, P

    1997-01-01

    Late stages of Plasmodium falciparum-infected erythrocytes (IRBCs) frequently sequester in the placentas of pregnant women, a phenomenon associated with low birth weight of the offspring. To investigate the physiological mechanism of this sequestration, we developed an in vitro assay for studying the cytoadherence of IRBCs to cultured term human trophoblasts. The capacity for binding to the syncytiotrophoblast varied greatly among P. falciparum isolates and was mediated by intercellular adhesion molecule 1 (ICAM-1), as binding was totally inhibited by 84H10, a monoclonal antibody specific for ICAM-1. Binding of the P. falciparum line RP5 to the syncytiotrophoblast involves chondroitin-4-sulfate (CSA), as this binding was dramatically impaired by addition of free CSA to the binding medium or by preincubation of the syncytiotrophoblast with chondroitinase ABC. ICAM-1 and CSA were visualized on the syncytiotrophoblast by immunofluorescence, while CD36, E-selectin, and vascular cell adhesion molecule 1 were not expressed even on tumor necrosis factor alpha (TNF-alpha)-stimulated syncytiotrophoblast tissue, and monoclonal antibodies against these cell adhesion molecules did not inhibit cytoadherence. ICAM-1 expression and cytoadherence of wild isolates was upregulated by TNF-alpha, a cytokine that can be secreted by the numerous mononuclear phagocytes present in malaria-infected placentas. These results suggest that cytoadherence may be involved in the placental sequestration and broaden the understanding of the physiopathology of the malaria-infected placenta. PMID:9119459

  13. Serum Proteomic Signature of Human Chagasic Patients for the Identification of Novel Potential Protein Biomarkers of Disease*

    PubMed Central

    Wen, Jian-Jun; Zago, M. Paola; Nuñez, Sonia; Gupta, Shivali; Burgos, Federico Nuñez; Garg, Nisha Jain

    2012-01-01

    Chagas disease is initiated upon infection by Trypanosoma cruzi. Among the health consequences is a decline in heart function, and the pathophysiological mechanisms underlying this manifestation are not well understood. To explore the possible mechanisms, we employed IgY LC10 affinity chromatography in conjunction with ProteomeLab PF2D and two-dimensional gel electrophoresis to resolve the proteome signature of high and low abundance serum proteins in chagasic patients. MALDI-TOF MS/MS analysis yielded 80 and 14 differentially expressed proteins associated with cardiomyopathy of chagasic and other etiologies, respectively. The extent of oxidative stress-induced carbonyl modifications of the differentially expressed proteins (n = 26) was increased and coupled with a depression of antioxidant proteins. Functional annotation of the top networks developed by ingenuity pathway analysis of proteome database identified dysregulation of inflammation/acute phase response signaling and lipid metabolism relevant to production of prostaglandins and arachidonic acid in chagasic patients. Overlay of the major networks identified prothrombin and plasminogen at a nodal position with connectivity to proteome signature indicative of heart disease (i.e., thrombosis, angiogenesis, vasodilatation of blood vessels or the aorta, and increased permeability of blood vessel and endothelial tubes), and inflammatory responses (e.g., platelet aggregation, complement activation, and phagocyte activation and migration). The detection of cardiac proteins (myosin light chain 2 and myosin heavy chain 11) and increased levels of vinculin and plasminogen provided a comprehensive set of biomarkers of cardiac muscle injury and development of clinical Chagas disease in human patients. These results provide an impetus for biomarker validation in large cohorts of clinically characterized chagasic patients. PMID:22543060

  14. Placenta-derived exosomes and syncytiotrophoblast microparticles and their role in human reproduction: immune modulation for pregnancy success.

    PubMed

    Mincheva-Nilsson, Lucia; Baranov, Vladimir

    2014-11-01

    The syncytiotrophoblast (STB) of human placenta constitutively produces and secretes extracellular vesicles of different size, morphology and function that enter the maternal circulation, and participate in the maternal-fetal cross-talk during pregnancy. Syncytiotrophoblast-derived microvesicles/microparticles (STBM) are larger microvesicles (0.2-2 μm) shed by the apical plasma membrane of the STB as a result of cell activation and turnover. Simultaneously with the STBM shedding, the STB produces and secretes exosomes--nanosized (30-100/150 nm) membrane-bound microvesicles that originate from the endosomal compartment. They convey cell-cell contact 'by proxy' transporting signals/packages of information between donor and recipient cells locally or/and at a distance. STBM and exosomes, delivered directly in the maternal blood surrounding the chorionic villi of the placenta, have contrasting biological functions. While the exosomes are immunosuppressive down regulating maternal immunity in pluripotent ways, the main effects of STBM on the maternal immune system are pro-inflammatory, immune activating, and pro-coagulant. Since both STBM and exosomes are present in the maternal circulation throughout normal pregnancy logical questions are what is the net effect of these vesicles on the maternal immune system and is this effect beneficial or detrimental to pregnancy. In this review, the current knowledge about placenta-derived extracellular vesicles with a main focus on exosomes is summarized and discussed. In a concluding remark, a hypothetical proposal on how STBM and exosomes might interact in pregnancy is discussed and a way to evaluate this interaction is suggested. PMID:25164206

  15. Cross talk between cAMP and p38 MAPK pathways in the induction of leptin by hCG in human placental syncytiotrophoblasts.

    PubMed

    Ge, Y C; Li, J N; Ni, X T; Guo, C M; Wang, W S; Duan, T; Sun, K

    2011-08-01

    Leptin produced by the placental syncytiotrophoblasts participates in a number of processes in pregnancy including implantation, proliferation of the cytotrophoblasts, and nutrient transfer across the placenta. Despite the functional significance of leptin in pregnancy, the regulation of leptin synthesis is poorly understood in human placental syncytiotrophoblasts. In this study, we investigated the role of endogenous human chorionic gonadotropin (hCG) in the regulation of leptin production as well as the underlying mechanism involving the cross talk between cAMP and p38 mitogen-activated protein kinase (MAPK) pathways. We found that neutralization of endogenous hCG with its antibody dose dependently decreased leptin mRNA level and secretion, whereas exogenous hCG increased leptin mRNA level and secretion. Activation of the cAMP pathway with dibutyryl cAMP (db cAMP) or forskolin recapitulated the stimulatory effect of hCG on leptin expression. Inhibition of protein kinase A with H89 not only reduced the basal leptin expression but also attenuated the induced leptin expression by hCG. Treatment of the syncytiotrophoblasts with db cAMP and hCG phosphorylated p38 MAPK. Inhibition of p38 MAPK with SB203580 not only reduced the basal leptin production but also attenuated the leptin-induced production by both hCG and db cAMP. These data suggest that endogenous hCG plays a significant role in maintaining leptin production in human placental syncytiotrophoblasts, and this effect involves a cross talk between cAMP and p38 MAPK pathways. PMID:21562093

  16. Syncytiotrophoblast Functions and Fetal Growth Restriction during Placental Malaria: Updates and Implication for Future Interventions

    PubMed Central

    Kidima, Winifrida B.

    2015-01-01

    Syncytiotrophoblast lines the intervillous space of the placenta and plays important roles in fetus growth throughout gestation. However, perturbations at the maternal-fetal interface during placental malaria may possibly alter the physiological functions of syncytiotrophoblast and therefore growth and development of the embryo in utero. An understanding of the influence of placental malaria on syncytiotrophoblast function is paramount in developing novel interventions for the control of placental pathology associated with placental malaria. In this review, we discuss how malaria changes syncytiotrophoblast function as evidenced from human, animal, and in vitro studies and, further, how dysregulation of syncytiotrophoblast function may impact fetal growth in utero. We also formulate a hypothesis, stemming from epidemiological observations, that nutrition may override pathogenesis of placental malaria-associated-fetal growth restriction. We therefore recommend studies on nutrition-based-interventional approaches for high placental malaria-risk women in endemic areas. More investigations on the role of nutrition on placental malaria pathogenesis are needed. PMID:26587536

  17. A three-dimensional culture system recapitulates placental syncytiotrophoblast development and microbial resistance

    PubMed Central

    McConkey, Cameron A.; Delorme-Axford, Elizabeth; Nickerson, Cheryl A.; Kim, Kwang Sik; Sadovsky, Yoel; Boyle, Jon P.; Coyne, Carolyn B.

    2016-01-01

    In eutherians, the placenta acts as a barrier and conduit at the maternal-fetal interface. Syncytiotrophoblasts, the multinucleated cells that cover the placental villous tree surfaces of the human placenta, are directly bathed in maternal blood and are formed by the fusion of progenitor cytotrophoblasts that underlie them. Despite their crucial role in fetal protection, many of the events that govern trophoblast fusion and protection from microbial infection are unknown. We describe a three-dimensional (3D)–based culture model using human JEG-3 trophoblast cells that develop syncytiotrophoblast phenotypes when cocultured with human microvascular endothelial cells. JEG-3 cells cultured in this system exhibit enhanced fusogenic activity and morphological and secretory activities strikingly similar to those of primary human syncytiotrophoblasts. RNASeq analyses extend the observed functional similarities to the transcriptome, where we observed significant overlap between syncytiotrophoblast-specific genes and 3D JEG-3 cultures. Furthermore, JEG-3 cells cultured in 3D are resistant to infection by viruses and Toxoplasma gondii, which mimics the high resistance of syncytiotrophoblasts to microbial infections in vivo. Given that this system is genetically manipulatable, it provides a new platform to dissect the mechanisms involved in syncytiotrophoblast development and microbial resistance. PMID:26973875

  18. Chagasic Thymic Atrophy Does Not Affect Negative Selection but Results in the Export of Activated CD4+CD8+ T Cells in Severe Forms of Human Disease

    PubMed Central

    Morrot, Alexandre; Terra-Granado, Eugênia; Pérez, Ana Rosa; Silva-Barbosa, Suse Dayse; Milićević, Novica M.; Farias-de-Oliveira, Désio Aurélio; Berbert, Luiz Ricardo; De Meis, Juliana; Takiya, Christina Maeda; Beloscar, Juan; Wang, Xiaoping; Kont, Vivian; Peterson, Pärt; Bottasso, Oscar; Savino, Wilson

    2011-01-01

    Extrathymic CD4+CD8+ double-positive (DP) T cells are increased in some pathophysiological conditions, including infectious diseases. In the murine model of Chagas disease, it has been shown that the protozoan parasite Trypanosoma cruzi is able to target the thymus and induce alterations of the thymic microenvironment and the lymphoid compartment. In the acute phase, this results in a severe atrophy of the organ and early release of DP cells into the periphery. To date, the effect of the changes promoted by the parasite infection on thymic central tolerance has remained elusive. Herein we show that the intrathymic key elements that are necessary to promote the negative selection of thymocytes undergoing maturation during the thymopoiesis remains functional during the acute chagasic thymic atrophy. Intrathymic expression of the autoimmune regulator factor (Aire) and tissue-restricted antigen (TRA) genes is normal. In addition, the expression of the proapoptotic Bim protein in thymocytes was not changed, revealing that the parasite infection-induced thymus atrophy has no effect on these marker genes necessary to promote clonal deletion of T cells. In a chicken egg ovalbumin (OVA)-specific T-cell receptor (TCR) transgenic system, the administration of OVA peptide into infected mice with thymic atrophy promoted OVA-specific thymocyte apoptosis, further indicating normal negative selection process during the infection. Yet, although the intrathymic checkpoints necessary for thymic negative selection are present in the acute phase of Chagas disease, we found that the DP cells released into the periphery acquire an activated phenotype similar to what is described for activated effector or memory single-positive T cells. Most interestingly, we also demonstrate that increased percentages of peripheral blood subset of DP cells exhibiting an activated HLA-DR+ phenotype are associated with severe cardiac forms of human chronic Chagas disease. These cells may contribute to the

  19. Cardiac condition in young chagasic women

    PubMed Central

    Lassen, O; Dotto, G; Ojeda, S; Garutti, A; Bertolotto, P; Tabares, S; Gallerano, R; Sembaj, A

    2013-01-01

    Rationale: Chagas disease is a complex disorder caused by Trypanosoma cruzi. Most patients remain asymptomatic for several years and 30% of them progress quietly to developing cardiomyopathy. The factors that lead to chronic myocardial lesions are not fully understood. Objective: To investigate the association between clinical symptoms and single nucleotide polymorphisms in chagasic and non-chagasic women younger and older than 55 years of age. Methods and Results: we analyzed Ala-9Val and Ile58Thr polymorphisms of the SOD-Mn gene, 138ex1ins/del A of the endothelin-1 gene (ET-1) and H323H (T/C) of the endothelin receptor A gene (ETA), by PCR-RFLP using genomic DNA from leukocyte of 85 women. We also evaluated serum lipid profile, renal and liver function, chest X-rays, electrocardiograms (ECGs) and echocardiography (EchoCG). Biochemical profiling did not show differences between chagasic and non-chagasic patients. The polymorphisms analyses showed a significant association in the distribution of frequencies of the Mn-SOD Ile58Thr gene between both groups. Young chagasic patients had a significantly higher prevalence of abnormalities in X-rays, in ECGs and they showed grade II and III of NYHA functional classes. The chance of having an abnormal EchoCG was 5.87 higher in young chagasic patients (OR=5.87, 95% CI 1.47-23.4). Discussion: We concluded that the parasite affects young females by accelerating the deterioration of cardiac function, independent of other cardiovascular risk factors and the cardioprotective action of estrogens present in the premenopausal stage. PMID:23904881

  20. HLA antigens in cardiomyopathic Chilean chagasics.

    PubMed Central

    Llop, E; Rothhammer, F; Acuña, M; Apt, W

    1988-01-01

    The distribution of HLA antigens in a sample of 124 Chagas serologically positive Chilean individuals was studied. The sample was subdivided according to the presence or absence of chagasic cardiomyopathy, in order to search for genetic differences associated with this pathological condition. The frequency of antigen B40 in the presence of antigen Cw3 was found to be significantly lower in subjects with cardiomyopathy. We tentatively suggest that the presence of these antigens among noncardiomyopathics is associated with a decreased susceptibility to develop chagasic cardiomyopathy in the Chilean population. PMID:3189340

  1. Quantitative analysis of cardiac lesions in chronic canine chagasic cardiomyopathy.

    PubMed

    Caliari, Marcelo Vidigal; do Pilar Machado, Raquel; de Lana, Marta; Caja, Rosângela Aparecida França; Carneiro, Cláudia Martins; Bahia, Maria Teresinha; dos Santos, César Augusto Bueno; Magalhaes, Gustavo Albergaria; Sampaio, Ivan Barbosa Machado; Tafuri, Washington Luiz

    2002-01-01

    Lesions observed in chronic chagasic cardiopathy frequently produce electrocardiographic alterations and affect cardiac function. Through a computerized morphometrical analysis we quantified the areas occupied by cardiac muscle, connective and adipose tissues in the right atrium of dogs experimentally infected with Trypanosoma cruzi. All of the infected dogs showed chronic myocarditis with variable reduction levels of cardiac muscle, fibrosis and adipose tissue replacement. In the atrial myocardium of dogs infected with Be78 and Be62 cardiac muscle represented 34 and 50%, fibrosis 28 and 32% and adipose tissue 38 and 18%, respectively. The fibrosis observed was both diffuse and focal and mostly intrafascicular, either partially or completely interrupting the path of muscle bundles. Such histological alterations probably contributed to the appearance of electrocardiographic disturbances verified in 10 out 11 dogs which are also common in human chronic chagasic cardiopathy. Fibrosis was the most important microscopic occurrence found since it produces rearrangements of collagen fibers in relation to myocardiocytes which causes changes in anatomical physiognomy and mechanical behavior of the myocardium. These abnormalities can contribute to the appearance of cardiac malfunction, arrythmias and congestive cardiac insufficiency as observed in two of the analyzed dogs. Strain Be78 caused destruction of atrial cardiac muscle higher than that induced by strain Be62. PMID:12436168

  2. The Immunomodulatory Role of Syncytiotrophoblast Microvesicles

    PubMed Central

    Southcombe, Jennifer; Tannetta, Dionne; Redman, Christopher; Sargent, Ian

    2011-01-01

    Immune adaptation is a critical component of successful pregnancy. Of primary importance is the modification of cytokine production upon immune activation. With the discovery that normal pregnancy itself is a pro-inflammatory state, it was recognised that the classical Th1/Th2 cytokine paradigm, with a shift towards ‘type 2’ cytokine production (important for antibody production), and away from ‘type 1’ immunity (associated with cell mediated immunity and graft rejection), is too simplistic. It is now generally agreed that both arms of cytokine immunity are activated, but with a bias towards ‘type 2’ immunity. Many factors are released from the placenta that can influence the maternal cytokine balance. Here we focus on syncytiotrophoblast microvesicles (STBM) which are shed from the placenta into the maternal circulation. We show that STBM can bind to monocytes and B cells and induce cytokine release (TNFα, MIP-1α, IL-1α, IL-1β, IL-6, IL-8). Other cytokines are down-modulated, such as IP-10 which is associated with ‘type 1’ immunity. Therefore STBM may aid the ‘type 2’ skewed nature of normal pregnancy. We also observed that PBMC from third trimester normal pregnant women produce more TNFα and IL-6 in response to STBM than PBMC from non-pregnant women, confirming that maternal immune cells are primed by pregnancy, possibly through their interaction with STBM. PMID:21633494

  3. Defect of villous cytotrophoblast differentiation into syncytiotrophoblast in Down's syndrome.

    PubMed

    Frendo, J L; Vidaud, M; Guibourdenche, J; Luton, D; Muller, F; Bellet, D; Giovagrandi, Y; Tarrade, A; Porquet, D; Blot, P; Evain-Brion, D

    2000-10-01

    The syncytiotrophoblast (ST) is one of the major components of the human placenta, as it is involved in feto-maternal exchanges and the secretion of pregnancy-specific hormones. The aim of this study was to elucidate the formation and function of the ST in trisomy 21 (Down's syndrome). We first used the in vitro model of cytotrophoblast differentiation into ST. Cytotrophoblasts were isolated from 15 trisomy 21-affected placentas (12-35 weeks gestation) and 10 gestational age-matched control placentas. In vitro cytotrophoblasts isolated from normal placenta fused to form the ST. This was associated with an increase in transcript levels and in the secretion of hCG, human placental lactogen, placental GH, and leptin. In trisomy 21-affected placentas, we observed a defect (or a delay) in ST formation and a dramatic decrease in the synthesis and secretion of these hormones compared to those in cultured cells isolated from control age-matched placentas. These results were confirmed by a significant (P < 0.001) decrease in gene expression in total homogenates of trisomy 21-affected placentas compared to controls. These results will be of help in understanding the maternal hormonal markers of fetal trisomy 21 and the consequences of placental defects for fetal development. PMID:11061527

  4. Do lymphocytes from Chagasic patients respond to heart antigens?

    PubMed Central

    Todd, C W; Todd, N R; Guimaraes, A C

    1983-01-01

    Lymphocyte transformation studies of nonadherent lymphocytes from chronic Chagasic and uninfected persons demonstrated that responses of all individuals to a mouse heart homogenate showed a correlation with responses to streptococcal antigens. Considering the known cross-reactions between streptococcal and cardiac antigens and the high reactivity of Chagasic patients to streptococcal antigens, it is possible that positive lymphocyte transformation to unfractionated heart antigen preparations may not represent specific reactivity to heart antigens. PMID:6404836

  5. Lower oesophageal sphincter response to pentagastrin in chagasic patients with megaoesophagus and megacolon.

    PubMed Central

    Padovan, W; Godoy, R A; Dantas, R O; Meneghelli, U G; Oliveira, R B; Troncon, L E

    1980-01-01

    Intraluminal manometric studies were performed in 14 chagasic patients with megaoesophagus, 10 chagasic patients with megacolon, and 15 control subjects. Basal lower oesophageal sphincter pressure was 20.27+/-1.16 mmHg (mean+/-SEM) in controls as compared wtih 15.16+/-1.53 mmHg in chagasics with megaoesophagus and 14.38+/-1.50 mmHg in chagasics with megacolon. Dose-response studies to intravenous pentagastrin showed that the chagasic patients exhibited a lower sensitivity to the stimulant than did the controls, as demonstrated by shifting of the dose-response curve to the right and higher individual values of the dose for half maximal contraction (D50). No difference was noted between the calculated maximal contraction (Vmax) of oesophageal sphincter of controls and chagasics. These data are compatible with the hypothesis of an interaction between pentagastrin and cholinergic nervous excitation on oesophageal sphincteric smooth muscle. PMID:6769753

  6. Transplanted Bone Marrow Cells Repair Heart Tissue and Reduce Myocarditis in Chronic Chagasic Mice

    PubMed Central

    Soares, Milena B. P.; Lima, Ricardo S.; Rocha, Leonardo L.; Takyia, Christina M.; Pontes-de-Carvalho, Lain; Campos de Carvalho, Antonio C.; Ribeiro-dos-Santos, Ricardo

    2004-01-01

    A progressive destruction of the myocardium occurs in ∼30% of Trypanosoma cruzi-infected individuals, causing chronic chagasic cardiomyopathy, a disease so far without effective treatment. Syngeneic bone marrow cell transplantation has been shown to cause repair and improvement of heart function in a number of studies in patients and animal models of ischemic cardiopathy. The effects of bone marrow transplant in a mouse model of chronic chagasic cardiomyopathy, in the presence of the disease causal agent, ie, the T. cruzi, are described herein. Bone marrow cells injected intravenously into chronic chagasic mice migrated to the heart and caused a significant reduction in the inflammatory infiltrates and in the interstitial fibrosis characteristics of chronic chagasic cardiomyopathy. The beneficial effects were observed up to 6 months after bone marrow cell transplantation. A massive apoptosis of myocardial inflammatory cells was observed after the therapy with bone marrow cells. Transplanted bone marrow cells obtained from chagasic mice and from normal mice had similar effects in terms of mediating chagasic heart repair. These results show that bone marrow cell transplantation is effective for treatment of chronic chagasic myocarditis and indicate that autologous bone marrow transplant may be used as an efficient therapy for patients with chronic chagasic cardiomyopathy. PMID:14742250

  7. [Migration flow and imported diseases: chronic chagasic cardiomyopathy].

    PubMed

    Guerri-Guttenberg, Roberto A; Di Girolamo, Chiara; Ciannameo, Anna; Milei, José

    2009-04-01

    Chagas disease, caused by the parasite Trypanosoma cruzi, is transmitted by triatomine bugs in endemic regions of the American continent and less frequently by blood transfusion and congenital transmission. Immigration rates explain why the disease can be found worldwide. Non-endemic countries that receive a significant amount of Latin American immigrants should be familiarized with the disease to allow prevention, diagnosis and early treatment. In Italy, where no serologic screening is routinely performed to detect Trypanosoma cruzi in blood donations, a special consideration must be held. Accordingly, attention to congenital transmissions of the disease should be drawn considering the lack of newborn screening. Though commonly unrecognized, chronic chagasic cardiomyopathy is the most common type of chronic myocarditis in the world. PMID:19475878

  8. Increased CD4+/CD8+ Double-Positive T Cells in Chronic Chagasic Patients

    PubMed Central

    Giraldo, Nicolas A.; Bolaños, Natalia I.; Cuellar, Adriana; Guzman, Fanny; Uribe, Ana Maria; Bedoya, Astrid; Olaya, Natalia; Cucunubá, Zulma M.; Roa, Nubia; Rosas, Fernando; Velasco, Víctor; Puerta, Concepción J.; González, John M.

    2011-01-01

    Background CD4+/CD8+ double positive (DP) T cells have been described in healthy individuals as well as in patients with autoimmune and chronic infectious diseases. In chronic viral infections, this cell subset has effector memory phenotype and displays antigen specificity. No previous studies of double positive T cells in parasite infections have been carried out. Methodology/Principal Findings Seventeen chronic chagasic patients (7 asymptomatic and 10 symptomatic) and 24 non-infected donors, including 12 healthy and 12 with non-chagasic cardiomyopathy donors were analyzed. Peripheral blood was stained for CD3, CD4, CD8, HLA-DR and CD38, and lymphocytes for intracellular perforin. Antigen specificity was assessed using HLA*A2 tetramers loaded with T. cruzi K1 or influenza virus epitopes. Surface expression of CD107 and intracellular IFN-γ production were determined in K1-specific DP T cells from 11 chagasic donors. Heart tissue from a chronic chagasic patient was stained for both CD8 and CD4 by immunochemistry. Chagasic patients showed higher frequencies of DP T cells (2.1%±0.9) compared with healthy (1.1%±0.5) and non-chagasic cardiomyopathy (1.2%±0.4) donors. DP T cells from Chagasic patients also expressed more HLA-DR, CD38 and perforin and had higher frequencies of T. cruzi K1-specific cells. IFN-γ production in K1-specific cells was higher in asymptomatic patients after polyclonal stimulation, while these cells tended to degranulate more in symptomatic donors. Immunochemistry revealed that double positive T cells infiltrate the cardiac tissue of a chagasic donor. Conclusions Chagasic patients have higher percentages of circulating double positive T cells expressing activation markers, potential effector molecules and greater class I antigenic specificity against T. cruzi. Although K1 tetramer positive DP T cell produced little IFN-γ, they displayed degranulation activity that was increased in symptomatic patients. Moreover, K1-specific DP T cells can

  9. Effect of hypoxia on the calcium and magnesium content, lipid peroxidation level, and Ca²⁺-ATPase activity of syncytiotrophoblast plasma membranes from placental explants.

    PubMed

    Chiarello, Delia I; Marín, Reinaldo; Proverbio, Fulgencio; Benzo, Zully; Piñero, Sandy; Botana, Desirée; Abad, Cilia

    2014-01-01

    In the current study the possible relationship between the Ca(2+)/Mg(2+) ratio of human syncytiotrophoblast plasma membranes and their lipid peroxidation and Ca(2+)-ATPase activity was determined. Syncytiotrophoblast plasma membranes of placental explants cultured under hypoxia increased their lipid peroxidation and Ca(2+) content, diminished their Ca(2+)-ATPase activity, and kept their Mg(2+) content unchanged. Membranes preincubated with different concentrations of Ca(2+) increased their Ca(2+) content without changes in their Mg(2+) content. There is a direct relationship between Ca(2+) content and lipid peroxidation of the membranes, as well as an inverse relationship between their Ca(2+) content and Ca(2+)-ATPase activity. On the contrary, preincubation of membranes with different concentrations of Mg(2+) showed a higher Mg(2+) content without changing their lipid peroxidation and Ca(2+)-ATPase activity. Explants cultured under hypoxia in the presence of 4 mM MgSO4 showed similar values of lipid peroxidation and Ca(2+)-ATPase activity of their membranes compared to those of explants cultured under normoxia. Increased Ca(2+) content of the membranes by interacting with negatively charged phospholipids could result in destabilizing effects of the membrane structure, exposing hydrocarbon chains of fatty acids to the action of free radicals. Mg(2+) might exert a stabilizing effect of the membranes, avoiding their exposure to free radicals. PMID:25180187

  10. Effect of Hypoxia on the Calcium and Magnesium Content, Lipid Peroxidation Level, and Ca2+-ATPase Activity of Syncytiotrophoblast Plasma Membranes from Placental Explants

    PubMed Central

    Chiarello, Delia I.; Benzo, Zully; Piñero, Sandy; Botana, Desirée; Abad, Cilia

    2014-01-01

    In the current study the possible relationship between the Ca2+/Mg2+ ratio of human syncytiotrophoblast plasma membranes and their lipid peroxidation and Ca2+-ATPase activity was determined. Syncytiotrophoblast plasma membranes of placental explants cultured under hypoxia increased their lipid peroxidation and Ca2+ content, diminished their Ca2+-ATPase activity, and kept their Mg2+ content unchanged. Membranes preincubated with different concentrations of Ca2+ increased their Ca2+ content without changes in their Mg2+ content. There is a direct relationship between Ca2+ content and lipid peroxidation of the membranes, as well as an inverse relationship between their Ca2+ content and Ca2+-ATPase activity. On the contrary, preincubation of membranes with different concentrations of Mg2+ showed a higher Mg2+ content without changing their lipid peroxidation and Ca2+-ATPase activity. Explants cultured under hypoxia in the presence of 4 mM MgSO4 showed similar values of lipid peroxidation and Ca2+-ATPase activity of their membranes compared to those of explants cultured under normoxia. Increased Ca2+ content of the membranes by interacting with negatively charged phospholipids could result in destabilizing effects of the membrane structure, exposing hydrocarbon chains of fatty acids to the action of free radicals. Mg2+ might exert a stabilizing effect of the membranes, avoiding their exposure to free radicals. PMID:25180187

  11. Electrophysiological and pharmacological evaluation of the nicotinic cholinergic system in chagasic rats

    PubMed Central

    2013-01-01

    Background Two theories attempt to explain the changes observed in the nicotinic acetylcholine receptors (nAChRs) in chagasic cardiomyopathy. The neurogenic theory proposes that receptor changes are due to loss of intracardiac ganglia parasympathetic neurons. The immunogenic theory proposes that the nAChRs changes are the result of autoantibodies against these receptors. Both theories agreed that nAChRs functional expression could be impaired in Chagas disease. Methods We evaluated nAChRs functional integrity in 54 Sprague Dawley rats, divided in two groups: healthy and chronic chagasic rats. Rats were subjected to electrocardiographic studies in the whole animal under pentobarbital anesthesia, by isolation and stimulation of vagus nerves and in isolated beating hearts (Langendorff’s preparation). Results Nicotine, 10 μM, induced a significant bradycardia in both groups. However, rats that had previously received reserpine did not respond to nicotine stimulation. β-adrenergic stimulation, followed by nicotine treatment, induced tachycardia in chagasic rats; while inducing bradycardia in healthy rats. Bilateral vagus nerve stimulation induced a significantly higher level of bradycardia in healthy rats, compared to chagasic rats; physostigmine potentiated the bradycardic response to vagal stimulation in both experimental groups. Electric stimulation (e.g., ≥ 2 Hz), in the presence of physostigmine, produced a comparable vagal response in both groups. In isolated beating-heart preparations 1 μM nicotine induced sustained bradycardia in healthy hearts while inducing tachycardia in chagasic hearts. Higher nicotine doses (e.g.,10 – 100 uM) promoted the characteristic biphasic response (i.e., bradycardia followed by tachycardia) in both groups. 10 nM DHβE antagonized the effect of 10 μM nicotine, unmasking the cholinergic bradycardic effect in healthy rats only. 1 nM α-BGT alone induced bradycardia in healthy hearts but antagonized the 10 μM nicotine

  12. Syncytiotrophoblast Extracellular Vesicles from Pre-Eclampsia Placentas Differentially Affect Platelet Function

    PubMed Central

    Tannetta, Dionne S.; Hunt, Kathryn; Jones, Chris I.; Davidson, Naomi; Coxon, Carmen H.; Ferguson, David; Redman, Christopher W.; Gibbins, Jonathan M.; Sargent, Ian L.; Tucker, Katherine L.

    2015-01-01

    Pre-eclampsia (PE) complicates around 3% of all pregnancies and is one of the most common causes of maternal mortality worldwide. The pathophysiology of PE remains unclear however its underlying cause originates from the placenta and manifests as raised blood pressure, proteinuria, vascular or systemic inflammation and hypercoagulation in the mother. Women who develop PE are also at significantly higher risk of subsequently developing cardiovascular (CV) disease. In PE, the failing endoplasmic reticulum, oxidative and inflammatory stressed syncytiotrophoblast layer of the placenta sheds increased numbers of syncytiotrophoblast extracellular vesicles (STBEV) into the maternal circulation. Platelet reactivity, size and concentration are also known to be altered in some women who develop PE, although the underlying reasons for this have not been determined. In this study we show that STBEV from disease free placenta isolated ex vivo by dual placental perfusion associate rapidly with platelets. We provide evidence that STBEV isolated from normal placentas cause platelet activation and that this is increased with STBEV from PE pregnancies. Furthermore, treatment of platelets with aspirin, currently prescribed for women at high risk of PE to reduce platelet aggregation, also inhibits STBEV-induced reversible aggregation of washed platelets. Increased platelet reactivity as a result of exposure to PE placenta derived STBEVs correlates with increased thrombotic risk associated with PE. These observations establish a possible direct link between the clotting disturbances of PE and dysfunction of the placenta, as well as the known increased risk of thromboembolism associated with this condition. PMID:26551971

  13. The identification and characterization of epitopes in the 30-34 kDa Trypanosoma cruzi proteins recognized by antibodies in the serum samples of chagasic patients.

    PubMed

    Verissimo da Costa, Giovani Carlo; Lery, Leticia Miranda Santos; da Silva, Manuela Leal; Moura, Hércules; Peralta, Regina Helena Saramago; von Krüger, Wanda Maria Almeida; Bisch, Paulo Mascarello; Barr, John R; Peralta, José Mauro

    2013-03-27

    Trypanosoma cruzi proteins with molecular weight between 30 and 34 kDa have shown high reactivity in western blot assays with serum samples from chagasic individuals. However, in-depth analysis of the constituents of these protein fractions has not been performed. This is the first report of an immunoaffinity proteomic approach to identify the immunodominant 30-34 kDa proteins of T. cruzi that could eventually be used for the diagnosis of Chagas disease. We used two different sample preparation protocols for protein digestion coupled to mass spectrometry to identify proteins in the protein fraction. The immunodominant proteins and their respective epitopes were then identified by co-immunoprecipitation and excision-epitope mapping/mass spectrometry, using human sera followed by the prediction and three-dimensional structural modeling of reactive epitopes. The use of different sample preparation methods allowed the identification of a relatively high number of proteins, some of which were only identified after one or multiple sample preparation and digestion protocols. Seven immunodominant proteins were identified by co-immunoprecipitation with purified IgGs from chagasic serum samples. Moreover, six reactive peptide epitopes were detected in four of these proteins by excision-epitope mapping/mass spectrometry. Three-dimensional structural models were obtained for the immunoreactive peptides, which correlated well with the linear B-cell epitope prediction tools. PMID:23159400

  14. Isolation of syncytiotrophoblast microvesicles and exosomes and their characterisation by multicolour flow cytometry and fluorescence Nanoparticle Tracking Analysis.

    PubMed

    Dragovic, R A; Collett, G P; Hole, P; Ferguson, D J P; Redman, C W; Sargent, I L; Tannetta, D S

    2015-10-01

    The human placenta releases multiple types and sizes of syncytiotrophoblast (STB) extracellular vesicles (EV) into the maternal circulation that exhibit diverse biological activities. The placental perfusion technique enables isolation of these STBEV, but conventional flow cytometry can only be used to phenotype EV down to ∼300 nm in size. Fluorescence Nanoparticle Tracking Analysis (fl-NTA) has the potential to phenotype EV down to ∼50 nm, thereby improving current characterisation techniques. The aims of this study were to prepare microvesicle and exosome enriched fractions from human placental perfusate (n=8) and improve fl-NTA STBEV detection. Differential centrifugation and filtration effectively removed contaminating red blood cells from fresh placental perfusates and pelleted a STB microvesicle (STBMV) fraction (10,000×g pellet - 10KP; NTA modal size 395±12 nm), enriched for the STB marker placental alkaline phosphatase (PLAP) and a STB exosome (STBEX) fraction (150,000×g pellet - 150KP; NTA modal size 147±6 nm), enriched for PLAP and exosome markers Alix and CD63. The PLAP positivity of 'standard' 10KP and 150KP pools (four samples/pool), determined by immunobead depletion, was used to optimise fl-NTA camera settings. Individual 10KP and 150KP samples (n=8) were 54.5±5.7% (range 17.8-66.9%) and 30.6±5.6% (range 3.3-51.7%) PLAP positive, respectively. We have developed a reliable method for enriching STBMV and STBEX from placental perfusate. We also standardised fl-NTA settings and improved measurement of PLAP positive EV in STBMV. However, fl-NTA is not as sensitive as anti-PLAP Dynabead capture for STBEX detection, possibly due to STBEX having lower surface expression of PLAP. These important developments will facilitate more detailed studies of the role of STBMV and STBEX in normal and pathological pregnancies. PMID:25843788

  15. Trypanosoma cruzi P21: a potential novel target for chagasic cardiomyopathy therapy

    PubMed Central

    Teixeira, Thaise Lara; Machado, Fabrício Castro; Alves da Silva, Aline; Teixeira, Samuel Cota; Borges, Bruna Cristina; dos Santos, Marlus Alves; Martins, Flávia Alves; Brígido, Paula Cristina; Rodrigues, Adele Aud; Notário, Ana Flávia Oliveira; Ferreira, Bruno Antônio; Servato, João Paulo Silva; Deconte, Simone Ramos; Lopes, Daiana Silva; Ávila, Veridiana Melo Rodrigues; Araújo, Fernanda de Assis; Tomiosso, Tatiana Carla; Silva, Marcelo José Barbosa; da Silva, Claudio Vieira

    2015-01-01

    Chagas disease, which is caused by the parasite Trypanosoma cruzi, is an important cause of cardiomyopathy in Latin America. It is estimated that 10%–30% of all infected individuals will acquire chronic chagasic cardiomyopathy (CCC). The etiology of CCC is multifactorial and involves parasite genotype, host genetic polymorphisms, immune response, signaling pathways and autoimmune progression. Herein we verified the impact of the recombinant form of P21 (rP21), a secreted T. cruzi protein involved in host cell invasion, on progression of inflammatory process in a polyester sponge-induced inflammation model. Results indicated that rP21 can recruit immune cells induce myeloperoxidase and IL-4 production and decrease blood vessels formation compared to controls in vitro and in vivo. In conclusion, T. cruzi P21 may be a potential target for the development of P21 antagonist compounds to treat chagasic cardiomyopathy. PMID:26574156

  16. Analysis of association of FOXO3 gene with Trypanosoma cruzi infection and chronic Chagasic cardiomyopathy.

    PubMed

    Leon Rodriguez, D A; González, C I; Martin, J

    2016-06-01

    FOXO3, a member of the Forkhead family of proteins, plays a role in controlling immune response. FOXO3 gene variant rs12212067 has been associated to differential severity of infectious diseases like malaria. In this study, we assessed whether this FOXO3 gene polymorphism is related to susceptibility to infection by Trypanosoma cruzi and/or chronic Chagasic cardiomyopathy. A total of 1171 individuals from a Colombian region endemic for Chagas disease, classified as seronegative (n = 595), seropositive asymptomatic (n = 175) and chronic Chagasic cardiomyopathy (n = 401) were genotyped for the FOXO3 rs12212067 using TaqMan allelic discrimination. Our results showed no statistically significantly differences between allelic and genotypic frequencies of rs12212067 in seronegative individuals compared with seropositive individuals. Similarly, we observed no evidence of association when asymptomatic individuals were compared with chronic Chagasic cardiomyopathy patients. Our data suggest that the FOXO3 genetic variant rs12212067 do not play an important role in Chagas disease. PMID:27125259

  17. Isolation of syncytiotrophoblast microvesicles and exosomes and their characterisation by multicolour flow cytometry and fluorescence Nanoparticle Tracking Analysis

    PubMed Central

    Dragovic, R.A.; Collett, G.P.; Hole, P.; Ferguson, D.J.P.; Redman, C.W.; Sargent, I.L.; Tannetta, D.S.

    2015-01-01

    The human placenta releases multiple types and sizes of syncytiotrophoblast (STB) extracellular vesicles (EV) into the maternal circulation that exhibit diverse biological activities. The placental perfusion technique enables isolation of these STBEV, but conventional flow cytometry can only be used to phenotype EV down to ∼300 nm in size. Fluorescence Nanoparticle Tracking Analysis (fl-NTA) has the potential to phenotype EV down to ∼50 nm, thereby improving current characterisation techniques. The aims of this study were to prepare microvesicle and exosome enriched fractions from human placental perfusate (n = 8) and improve fl-NTA STBEV detection. Differential centrifugation and filtration effectively removed contaminating red blood cells from fresh placental perfusates and pelleted a STB microvesicle (STBMV) fraction (10,000×g pellet – 10KP; NTA modal size 395 ± 12 nm), enriched for the STB marker placental alkaline phosphatase (PLAP) and a STB exosome (STBEX) fraction (150,000×g pellet – 150KP; NTA modal size 147 ± 6 nm), enriched for PLAP and exosome markers Alix and CD63. The PLAP positivity of ‘standard’ 10KP and 150KP pools (four samples/pool), determined by immunobead depletion, was used to optimise fl-NTA camera settings. Individual 10KP and 150KP samples (n = 8) were 54.5 ± 5.7% (range 17.8–66.9%) and 30.6 ± 5.6% (range 3.3–51.7%) PLAP positive, respectively. We have developed a reliable method for enriching STBMV and STBEX from placental perfusate. We also standardised fl-NTA settings and improved measurement of PLAP positive EV in STBMV. However, fl-NTA is not as sensitive as anti-PLAP Dynabead capture for STBEX detection, possibly due to STBEX having lower surface expression of PLAP. These important developments will facilitate more detailed studies of the role of STBMV and STBEX in normal and pathological pregnancies. PMID:25843788

  18. Alteration of syncytiotrophoblast mitochondria function and endothelial nitric oxide synthase expression in the placenta of rural residents.

    PubMed

    Rivero Osimani, Valeria L; Valdez, Susana R; Guiñazú, Natalia; Magnarelli, Gladis

    2016-06-01

    The impact of environmental organophosphate (OP) pesticide exposure on respiratory complexes, enzymatic antioxidant defense activities, and oxidative damage markers in the syncytiotrophoblast and cytotrophoblast mitochondria was evaluated. Placental progesterone (PG) levels and endothelial nitric oxide synthase (eNOS) expression were studied. Samples from women non-exposed (control group-CG) and women living in a rural area (rural group-RG) were collected during pesticide spraying season (RG-SS) and non-spraying season (RG-NSS). In RG-SS, the exposure biomarker placental carboxylesterase decreased and syncytiotrophoblast cytochrome c oxidase activity increased, while 4-hydroxynonenal levels decreased. PG levels decreased in RG-SS and in the RG. Nitric oxide synthase expression decreased in RG, RG-SS and RG-NSS. No significant changes in mitochondrial antioxidant enzyme activities were found. These results suggest that the alteration of syncytiotrophoblast mitochondrial complex IV activity and steroidogenic function may be associated to pesticide exposure. Reduction in placental PG and eNOS expression may account for low newborn weight in RG. PMID:26939719

  19. Gene expression analysis in mitochondria from chagasic mice: alterations in specific metabolic pathways

    PubMed Central

    2004-01-01

    Cardiac hypertrophy and remodelling in chagasic disease might be associated with mitochondrial dysfunction. In the present study, we characterized the cardiac metabolic responses to Trypanosoma cruzi infection and progressive disease severity using a custom-designed mitoarray (mitochondrial function-related gene array). Mitoarrays consisting of known, well-characterized mitochondrial function-related cDNAs were hybridized with 32P-labelled cDNA probes generated from the myocardium of mice during immediate early, acute and chronic phases of infection and disease development. The mitoarray successfully identified novel aspects of the T. cruzi-induced alterations in the expression of the genes related to mitochondrial function and biogenesis that were further confirmed by real-time reverse transcriptase–PCRs. Of note is the up-regulation of transcripts essential for fatty acid metabolism associated with repression of the mRNAs for pyruvate dehydrogenase complex in infected hearts. We observed no statistically significant changes in mRNAs for the enzymes of tricarboxylic acid cycle. These results suggest that fatty acid metabolism compensates the pyruvate dehydrogenase complex deficiencies for the supply of acetyl-CoA for a tricarboxylic acid cycle, and chagasic hearts may not be limited in reduced energy (NADH and FADH2). The observation of a decrease in mRNA level for several subunits of the respiratory chain complexes by mitoarray as well as global genome analysis suggests a limitation in mitochondrial oxidative phosphorylation-mediated ATP-generation capacity as the probable basis for cardiac homoeostasis in chagasic disease. PMID:15101819

  20. Chagas Cardiomyopathy Manifestations and Trypanosoma cruzi Genotypes Circulating in Chronic Chagasic Patients

    PubMed Central

    Ramírez, Juan David; Guhl, Felipe; Rendón, Lina María; Rosas, Fernando; Marin-Neto, Jose A.; Morillo, Carlos A.

    2010-01-01

    Chagas disease caused by Trypanosoma cruzi is a complex disease that is endemic and an important problem in public health in Latin America. The T. cruzi parasite is classified into six discrete taxonomic units (DTUs) based on the recently proposed nomenclature (TcI, TcII, TcIII, TcIV, TcV and TcVI). The discovery of genetic variability within TcI showed the presence of five genotypes (Ia, Ib, Ic, Id and Ie) related to the transmission cycle of Chagas disease. In Colombia, TcI is more prevalent but TcII has also been reported, as has mixed infection by both TcI and TcII in the same Chagasic patient. The objectives of this study were to determine the T. cruzi DTUs that are circulating in Colombian chronic Chagasic patients and to obtain more information about the molecular epidemiology of Chagas disease in Colombia. We also assessed the presence of electrocardiographic, radiologic and echocardiographic abnormalities with the purpose of correlating T. cruzi genetic variability and cardiac disease. Molecular characterization was performed in Colombian adult chronic Chagasic patients based on the intergenic region of the mini-exon gene, the 24Sα and 18S regions of rDNA and the variable region of satellite DNA, whereby the presence of T.cruzi I, II, III and IV was detected. In our population, mixed infections also occurred, with TcI-TcII, TcI-TcIII and TcI-TcIV, as well as the existence of the TcI genotypes showing the presence of genotypes Ia and Id. Patients infected with TcI demonstrated a higher prevalence of cardiac alterations than those infected with TcII. These results corroborate the predominance of TcI in Colombia and show the first report of TcIII and TcIV in Colombian Chagasic patients. Findings also indicate that Chagas cardiomyopathy manifestations are more correlated with TcI than with TcII in Colombia. PMID:21152056

  1. QRS slopes for assessment of myocardial damage in chronic chagasic patients

    NASA Astrophysics Data System (ADS)

    Pueyo, E.; Laciar, E.; Anzuola, E.; Laguna, P.; Jané, R.

    2007-11-01

    In this study the slopes of the QRS complex are evaluated for determination of the degree of myocardial damage in chronic chagasic patients. Previous studies have demonstrated the ability of the slope indices to reflect alterations in the conduction velocity of the cardiac impulse. Results obtained in the present study show that chronic chagasic patients have significantly flatter QRS slopes as compared to healthy subjects. Not only that but the extent of slope lessening turns out to be proportional to the degree of myocardial damage caused by the disease. Additionally, when incorporating the slope indices into a classification analysis together with other indices indicative of the presence of ventricular late potentials obtained from high resolution electrocardiography, results show that the percentages of correct classification increase up to 62.5%, which means eight points above the percentages obtained prior to incorporation of the slope indices. It can be concluded that QRS slopes have great potential for assessing the degree of severity associated with Chagas' disease.

  2. [A missing name in the history of chagasic megaesophagus: Joseph Cooper Reinhardt (1809/10-1873)].

    PubMed

    Meneghelli, U G; de Rezende, J M; Troncon, L E; Madrid, N; de Moura, M L

    1998-01-01

    The book entitled "Brazil and the Brasilians", written by the Reverends Kidder and Fletcher and firstly published in the United States in 1857, reports the travels of these two missionaries throughout Brazil and includes a section entitled "A new disease". This section contains data regarding the clinical picture, the natural history and the epidemiology of a commom disease in Brazilian hinterland, which was known as "mal de engasgo". These informations were collected in 1855 by Rev. Fletcher from an anonymous North American physician, who worked in Limeira, State of São Paulo, and is called in the book merely as "Dr.-". The present work reports the results of an investigation carried out aiming at the identification of "Dr.-" and discloses documental evidence that "Dr.-" was actually Dr. Joseph Cooper Reinhardt (1809/10-1883). Dr. Reinhardt worked for many years in the citites of Limeira and Campinas, State of São Paulo, and probably had an extensive knowledge regarding the main features of this particular disease, which would be known, nearly 100 years later, as chagasic megaesophagus. The authors point out that, from now on, any account of the history of chagasic megaesophagus must include the name of Dr. Joseph Cooper Reinhardt. PMID:9711306

  3. Gene expression changes associated with myocarditis and fibrosis in hearts of mice with chronic chagasic cardiomyopathy

    PubMed Central

    Soares, Milena Botelho Pereira; de Lima, Ricardo Santana; Rocha, Leonardo Lima; Vasconcelos, Juliana Fraga; Rogatto, Silvia Regina; dos Santos, Ricardo Ribeiro; Iacobas, Sanda; Goldenberg, Regina Coeli; Iacobas, Dumitru Andrei; Tanowitz, Herbert Bernard; de Carvalho, Antonio Carlos Campos; Spray, David Conover

    2010-01-01

    Chronic chagasic cardiomyopathy is a leading cause of heart failure in Latin American countries. About 30% of Trypanosoma cruzi-infected individuals develop this severe symptomatic form of the disease, characterized by intense inflammatory response accompanied by fibrosis in the heart. We performed an extensive microarray analysis of hearts from a mouse model of this disease and determined significant alterations in expression of ∼12% of the sampled genes. Extensive upregulations were associated with immune-inflammatory responses (chemokines, adhesion molecules, cathepsins and MHC molecules) and fibrosis (extracellular matrix components, lysyl oxidase and Timp-1). Our results indicate potentially relevant factors involved in the pathogenesis of the disease that may provide new therapeutic targets in chronic Chagas' disease. PMID:20565256

  4. Anti-Trypanosoma cruzi and anti-laminin antibodies in chagasic patients after specific treatment.

    PubMed Central

    Gazzinelli, R T; Galvão, L M; Cardoso, J E; Cançado, J R; Krettli, A U; Brener, Z; Gazzinelli, G

    1988-01-01

    The antibody response to Trypanosoma cruzi epimastigote and trypomastigote stages, as well as to laminin, was studied in several groups of chagasic patients. In six patients who were cured of the parasite, the serum antibody titers as revealed by indirect immunofluorescence and hemagglutination tests against epimastigotes (conventional serology) and a complement-mediated lysis test with living trypomastigotes did not differ from those of normal individuals. In seven presumably cured patients, although the complement-mediated lysis test turned negative, conventional serology remained positive. Sera from this group of so-called "dissociated" patients presented significant lower mean antibody titers against epimastigote but not trypomastigote stages than did sera from 14 untreated patients (P less than 0.01). Most of the antibodies against trypomastigotes, including the residual levels found in cured patients, were absorbed by mouse laminin. In fact, significantly higher titers of anti-laminin antibodies were observed in sera from untreated chagasic patients (1.131 +/- 0.458) and cured patients (1.103 +/- 0.572) than in sera from eight normal individuals (0.459 +/- 0.402) (P less than 0.01). The anti-laminin titers were higher in sera of patients of blood group A or O than in those of patients of group B or AB. In Western blotting (immunoblotting) analysis against trypomastigotes, sera from chronic untreated patients recognized many polypeptide bands ranging from 26 to 160 kilodaltons, whereas no protein bands were observed with sera from cured patients. Only faint bands of parasite proteins were observed with sera of dissociated patients. In conjunction, the above data suggest that the anti-trypomastigote antibodies which persist after parasitological cure of patients with Chagas' disease are due mainly to cross-reactive epitopes from mouse laminin. PMID:3141467

  5. Roles of TauT and system A in cytoprotection of rat syncytiotrophoblast cell line exposed to hypertonic stress.

    PubMed

    Nishimura, T; Sai, Y; Fujii, J; Muta, M; Iizasa, H; Tomi, M; Deureh, M; Kose, N; Nakashima, E

    2010-11-01

    The purpose of this study was to clarify the cytoprotective mechanism(s) induced in a conditionally immortalized syncytiotrophoblast cell line (TR-TBT 18d-1) exposed to hypertonic conditions. Hypertonicity-induced apoptosis of TR-TBT 18d-1 cells, but this was blocked by addition of 1 mM taurine to the culture medium. TauT-knockdown using siRNA revealed that TauT is a major contributor to taurine uptake by TR-TBT 18d-1 cells, at least under normal conditions. Cellular uptake of [(3)H]taurine and [(14)C]betaine by TR-TBT 18d-1 cells cultured under hypertonic conditions was increased compared to that under normal conditions. TauT, BGT-1, ATA2 and HSP70 mRNAs were upregulated by hypertonicity, while OCTN2, ENT1 and CNT1 mRNAs were downregulated. [(3)H]Taurine uptake was strongly inhibited by TauT inhibitors such as hypotaurine and β-alanine. MeAIB, a system A specific substrate, inhibited hypertonic stress-induced [(14)C]betaine uptake. These results suggest that TauT and system A play cytoprotective roles in syncytiotrophoblasts exposed to hypertonic stress. PMID:20801504

  6. Enteric Neuronal Damage, Intramuscular Denervation and Smooth Muscle Phenotype Changes as Mechanisms of Chagasic Megacolon: Evidence from a Long-Term Murine Model of Tripanosoma cruzi Infection

    PubMed Central

    Duz, Ana Luiza Cassin; Cartelle, Christiane Teixeira; Noviello, Maria de Lourdes; Veloso, Vanja Maria; Bahia, Maria Terezinha; Almeida-Leite, Camila Megale; Arantes, Rosa Maria Esteves

    2016-01-01

    We developed a novel murine model of long-term infection with Trypanosoma cruzi with the aim to elucidate the pathogenesis of megacolon and the associated adaptive and neuromuscular intestinal disorders. Our intent was to produce a chronic stage of the disease since the early treatment should avoid 100% mortality of untreated animals at acute phase. Treatment allowed animals to be kept infected and alive in order to develop the chronic phase of infection with low parasitism as in human disease. A group of Swiss mice was infected with the Y strain of T. cruzi. At the 11th day after infection, a sub-group was euthanized (acute-phase group) and another sub-group was treated with benznidazole and euthanized 15 months after infection (chronic-phase group). Whole colon samples were harvested and used for studying the histopathology of the intestinal smooth muscle and the plasticity of the enteric nerves. In the acute phase, all animals presented inflammatory lesions associated with intense and diffuse parasitism of the muscular and submucosa layers, which were enlarged when compared with the controls. The occurrence of intense degenerative inflammatory changes and increased reticular fibers suggests inflammatory-induced necrosis of muscle cells. In the chronic phase, parasitism was insignificant; however, the architecture of Aüerbach plexuses was focally affected in the inflamed areas, and a significant decrease in the number of neurons and in the density of intramuscular nerve bundles was detected. Other changes observed included increased thickness of the colon wall, diffuse muscle cell hypertrophy, and increased collagen deposition, indicating early fibrosis in the damaged areas. Mast cell count significantly increased in the muscular layers. We propose a model for studying the long-term (15 months) pathogenesis of Chagasic megacolon in mice that mimics the human disease, which persists for several years and has not been fully elucidated. We hypothesize that the long

  7. Enteric Neuronal Damage, Intramuscular Denervation and Smooth Muscle Phenotype Changes as Mechanisms of Chagasic Megacolon: Evidence from a Long-Term Murine Model of Tripanosoma cruzi Infection.

    PubMed

    Campos, Camila França; Cangussú, Silvia Dantas; Duz, Ana Luiza Cassin; Cartelle, Christiane Teixeira; Noviello, Maria de Lourdes; Veloso, Vanja Maria; Bahia, Maria Terezinha; Almeida-Leite, Camila Megale; Arantes, Rosa Maria Esteves

    2016-01-01

    We developed a novel murine model of long-term infection with Trypanosoma cruzi with the aim to elucidate the pathogenesis of megacolon and the associated adaptive and neuromuscular intestinal disorders. Our intent was to produce a chronic stage of the disease since the early treatment should avoid 100% mortality of untreated animals at acute phase. Treatment allowed animals to be kept infected and alive in order to develop the chronic phase of infection with low parasitism as in human disease. A group of Swiss mice was infected with the Y strain of T. cruzi. At the 11th day after infection, a sub-group was euthanized (acute-phase group) and another sub-group was treated with benznidazole and euthanized 15 months after infection (chronic-phase group). Whole colon samples were harvested and used for studying the histopathology of the intestinal smooth muscle and the plasticity of the enteric nerves. In the acute phase, all animals presented inflammatory lesions associated with intense and diffuse parasitism of the muscular and submucosa layers, which were enlarged when compared with the controls. The occurrence of intense degenerative inflammatory changes and increased reticular fibers suggests inflammatory-induced necrosis of muscle cells. In the chronic phase, parasitism was insignificant; however, the architecture of Aüerbach plexuses was focally affected in the inflamed areas, and a significant decrease in the number of neurons and in the density of intramuscular nerve bundles was detected. Other changes observed included increased thickness of the colon wall, diffuse muscle cell hypertrophy, and increased collagen deposition, indicating early fibrosis in the damaged areas. Mast cell count significantly increased in the muscular layers. We propose a model for studying the long-term (15 months) pathogenesis of Chagasic megacolon in mice that mimics the human disease, which persists for several years and has not been fully elucidated. We hypothesize that the long

  8. Elevated levels of antibodies against sulphatide are present in all chronic chagasic and dilated cardiomyopathy sera.

    PubMed Central

    Avila, J L; Rojas, M; Carrasco, H

    1993-01-01

    A natural anti-sulphatide antibody was found to be present in the serum of every normal individual studied. The reactivity of the antibody was assessed by its interaction with galactosylceramide-I3-sulphate. Antigen-antibody binding was strongly blocked by 1 mM heparin, dextran sulphate and chondroitin sulphate A, and by 5 mM chondroitin sulphate B. Antibodies avidly absorb to rabbit erythrocytes, but discretely to rat erythrocytes, suggesting that they are different from galactocerebroside antibodies. Elevated levels of sulphatide antibodies were present in all of 102 chronic Trypanosoma cruzi-infected patients studied, but not in other patients having cutaneous or visceral leishmaniasis, T. rangeli infection or several other protozoal, helminthic or mycotic infections. Interestingly, 100% of 40 dilated cardiomyopathy patients also have elevated levels of sulphatide antibodies. As T. cruzi is rich in galactocerebroside sulphate, it is proposed that in chagasic patients this glycolipid could act as an immunogen, inducing elevated titres of sulphatide antibodies, which could be important in the pathogenesis of cardiac or peripheral nerve symptoms. PMID:8513577

  9. Clinical and Echocardiographic Predictors of Mortality in Chagasic Cardiomyopathy - Systematic Review

    PubMed Central

    Pereira, Clodoval de Barros; Markman, Brivaldo

    2014-01-01

    Diagnosis, prognosis and evaluation of death risk in Chagas cardiomyopathy still constitute a challenge due to the diversity of manifestations, which determine the importance of using echocardiography, tissue Doppler and biomarkers. To evaluate, within a systematic review, clinical and echocardiographic profiles of patients with chronic chagasic cardiomyopathy, which may be related to worse prognosis and major mortality risk. To perform the systematic review, we used Medline (via PubMed), LILACS and SciELO databases to identify 82 articles published from 1991 to 2012, with the following descriptors: echocardiography, mortality and Chagas disease. We selected 31 original articles, involving diagnostic and prognostic methods. The importance of Chagas disease has increased due to its emergence in Europe and United States, but most evidence came from Brazil. Among the predictors of worse prognosis and higher mortality risk are morphological and functional alterations in the left and right ventricles, evaluated by conventional echocardiography and tissue Doppler, as well as the increase in brain natriuretic peptide and troponin I concentrations. Recently, the evaluations of dyssynchrony, dysautonomia, as well as strain, strain rate and myocardial twisting were added to the diagnostic arsenal for the early differentiation of Chagas cardiomyopathy. Developments in imaging and biochemical diagnostic procedures have enabled more detailed cardiac evaluations, which demonstrate the early involvement of both ventricles, allowing a more accurate assessment of the mortality risk in Chagas disease. PMID:25004422

  10. Abundance of megalin and Dab2 is reduced in syncytiotrophoblast during placental malaria, which may contribute to low birth weight

    PubMed Central

    Lybbert, Jared; Gullingsrud, Justin; Chesnokov, Olga; Turyakira, Eleanor; Dhorda, Mehul; Guerin, Philippe J.; Piola, Patrice; Muehlenbachs, Atis; Oleinikov, Andrew V.

    2016-01-01

    Placental malaria caused by Plasmodium falciparum contributes to ~200,000 child deaths annually, mainly due to low birth weight (LBW). Parasitized erythrocyte sequestration and consequent inflammation in the placenta are common attributes of placental malaria. The precise molecular details of placental changes leading to LBW are still poorly understood. We hypothesized that placental malaria may disturb maternofetal exchange of vitamins, lipids, and hormones mediated by the multi-ligand (n ~ 50) scavenging/signaling receptor megalin, which is abundantly expressed in placenta but was not previously analyzed in pregnancy outcomes. We studied abundance of megalin and its intracellular adaptor protein Dab2 by immunofluorescence microscopy in placental biopsies from Ugandan women with (n = 8) and without (n = 20) active placental malaria. We found that: (a) abundances of both megalin (p = 0.01) and Dab2 (p = 0.006) were significantly reduced in brush border of syncytiotrophoblast of infected placentas; (b) amounts of megalin and Dab2 were strongly correlated (Spearman’s r = 0.53, p = 0.003); (c) abundances of megalin and Dab2 (p = 0.046) were reduced in infected placentas from women with LBW deliveries. This study provides first evidence that placental malaria infection is associated with reduced abundance of megalin transport/signaling system and indicate that these changes may contribute to the pathology of LBW. PMID:27072056

  11. CHAGASIC MENINGOENCEPHALITIS IN AN HIV INFECTED PATIENT WITH MODERATE IMMUNOSUPPRESSION: PROLONGED SURVIVAL AND CHALLENGES IN THE HAART ERA

    PubMed Central

    BUCCHERI, Renata; KASSAB, Maria José; de FREITAS, Vera Lucia Teixeira; da SILVA, Sheila Cristina Vicente; BEZERRA, Rita C.; KHOURY, Zarifa; SHIKANAI-YASUDA, Maria Aparecida; VIDAL, José E.

    2015-01-01

    The reactivation of Chagas disease in HIV infected patients presents high mortality and morbidity. We present the case of a female patient with confirmed Chagasic meningoencephalitis as AIDS-defining illness. Interestingly, her TCD4+ lymphocyte cell count was 318 cells/mm3. After two months of induction therapy, one year of maintenance with benznidazol, and early introduction of highly active antiretroviral therapy (HAART), the patient had good clinical, parasitological and radiological evolution. We used a qualitative polymerase chain reaction for the monitoring of T. cruzi parasitemia during and after the treatment. We emphasize the potential value of molecular techniques along with clinical and radiological parameters in the follow-up of patients with Chagas disease and HIV infection. Early introduction of HAART, prolonged induction and maintenance of antiparasitic therapy, and its discontinuation are feasible, in the current management of reactivation of Chagas disease. PMID:27049711

  12. CHAGASIC MENINGOENCEPHALITIS IN AN HIV INFECTED PATIENT WITH MODERATE IMMUNOSUPPRESSION: PROLONGED SURVIVAL AND CHALLENGES IN THE HAART ERA.

    PubMed

    Buccheri, Renata; Kassab, Maria José; Freitas, Vera Lucia Teixeira de; Silva, Sheila Cristina Vicente da; Bezerra, Rita C; Khoury, Zarifa; Shikanai-Yasuda, Maria Aparecida; Vidal, José E

    2015-12-01

    The reactivation of Chagas disease in HIV infected patients presents high mortality and morbidity. We present the case of a female patient with confirmed Chagasic meningoencephalitis as AIDS-defining illness. Interestingly, her TCD4+ lymphocyte cell count was 318 cells/mm3. After two months of induction therapy, one year of maintenance with benznidazol, and early introduction of highly active antiretroviral therapy (HAART), the patient had good clinical, parasitological and radiological evolution. We used a qualitative polymerase chain reaction for the monitoring of T. cruzi parasitemia during and after the treatment. We emphasize the potential value of molecular techniques along with clinical and radiological parameters in the follow-up of patients with Chagas disease and HIV infection. Early introduction of HAART, prolonged induction and maintenance of antiparasitic therapy, and its discontinuation are feasible, in the current management of reactivation of Chagas disease. PMID:27049711

  13. Antibodies with beta-adrenergic activity from chronic chagasic patients modulate the QT interval and M cell action potential duration

    PubMed Central

    Medei, Emiliano Horacio; Nascimento, José H.M.; Pedrosa, Roberto C.; Barcellos, Luciane; Masuda, Masako O.; Sicouri, Serge; Elizari, Marcelo V.; Campos de Carvalho, Antonio C.

    2009-01-01

    Aims The aim of this study was to investigate whether the sera from chronic chagasic patients (CChPs) with beta-1 adrenergic activity (Ab-β) can modulate ventricular repolarization. Beta-adrenergic activity has been described in CChP. It increases the L-type calcium current and heart rate in isolated hearts, but its effects on ventricular repolarization has not been described. Methods and results In isolated rabbit hearts, under pacing condition, QT interval was measured under Ab-β perfusion. Beta-adrenergic activity was also tested in guinea pig ventricular M cells. Furthermore, the immunoglobulin fraction (IgG-β) of the Ab-β was tested on Ito, ICa, and Iks currents in rat, rabbit, and guinea pig myocytes, respectively. Beta-adrenergic activity shortened the QT interval. This effect was abolished in the presence of propranolol. In addition, sera from CChP without beta-adrenergic activity (Ab-β) did not modulate QT interval. The M cell action potential duration (APD) was reversibly shortened by Ab-β. Atenolol inhibited this effect of Ab-β, and Ab- did not modulate the AP of M cells. Ito was not modulated by isoproterenol nor by IgG-β. However, IgG-β increased ICa and IKs. Conclusion The shortening of the QT interval and APD in M cells and the increase of IKs and ICa induced by IgG-β contribute to repolarization changes that may trigger malignant ventricular arrhythmias observed in patients with chronic chagasic or idiopathic cardiomyopathy. PMID:18515284

  14. Temporal expression of pro-inflammatory cytokines and inducible nitric oxide synthase in experimental acute Chagasic cardiomyopathy.

    PubMed Central

    Chandrasekar, B.; Melby, P. C.; Troyer, D. A.; Colston, J. T.; Freeman, G. L.

    1998-01-01

    To characterize the kinetics of myocardial cytokine and inducible nitric oxide synthase (iNOS) expression in acute Chagasic cardiomyopathy, we studied a rat model of acute Trypanosoma cruzi infection. Rats were euthanized 36 hours and 5, 10, and 15 days after infection, and hearts were collected for histology, mRNA, and protein analyses. Histological analysis of myocardium showed a progressive increase in the number of amastigotes and mononuclear inflammatory cells. Organisms were first detected 5 days after intraperitoneal inoculation as isolated nests and became numerous by day 15. Northern blot analysis of total RNA revealed no signal for interleukin (IL)-1beta or tumor necrosis factor (TNF)-alpha and a weak signal for IL-6 in control hearts. High levels of expression for the three genes were detected in the infected animals at 36 hours after infection. Although IL-1beta and IL-6 levels increased steadily up to 10 days, TNF-alpha levels were the highest at 5 days, remained high at 10 days, and declined thereafter. Western blot analysis showed similar results to that of mRNA expression. No signal was detected for iNOS in the controls, but both its mRNA and protein were found in the infected animals, with levels being highest at 15 days after infection. Immunohistochemistry revealed no iNOS immunoreactivity in uninfected animals, but intense iNOS staining was detected in blood vessels of infected animals, which decreased progressively with period of infection. Positive staining for iNOS in cardiomyocytes was first detected at 36 hours after infection (at a time when there was no histological inflammatory reaction), which steadily increased, being the highest at 15 days after infection. These results indicate that, in addition to mechanical damage by T. cruzi, substantial pro-inflammatory cytokine production within the myocardium is likely to participate in the pathophysiology of acute Chagasic cardiomyopathy. Images Figure 1 Figure 3 Figure 5 Figure 6 Figure 7

  15. [Risk factors associated with the diagnosis of chronic Chagasic miocardiopathy in seropositive individuals from Barinas state, Venezuela].

    PubMed

    González, Beatriz; Silva, Martha; Al-Atrache, Yusra; Delgado, Yelitze; Serrano, José Luis; Doccimo, Angelina; Hernández, Huber; Verde, Juan; Morillo, Daniela; Marín, Jaime; Concepción, Juan Luis; Bonfante-Cabarcas, Rafael; Rodríguez-Bonfante, Claudina

    2014-06-01

    This study evaluates the risk factors associated with the diagnosis of chronic chagasic miocardiopathy (CChM) in 115 seropositive individuals to anti-Trypanosoma cruzi antibodies, in Barinas state, Venezuela. Serology was performed with ELISA and MABA; while the CChM diagnosis was established by electrocardiography and echocardiography. A complete clinical history including epidemiological, personal/familiar antecedents and psychobiological habits, plus socioeconomic, psychosocial and alimentary habits interviews were performed for each individual. Risk factors were determined through binary logistic regression. Results showed that 81 patients (70,4%; CI 95% = 66.4-74.4) had criteria for CChM, of which 74 (64.4%; IC 95% = 60.2-68.6) were in phase II; while 34 (29.6%; IC 95% = 25.5-33.5) were in phase I of the disease and 7 (6.1%; IC 95% = 4.0-8.2) in phase III. In a one year period, two patients in phase III died of heart failure. The diagnosis of CChM was associated with hunting practice, maternal history of cardiopathies, chewing chimó, medical history of hypertension and apex beat visible; it was negatively associated with canned and preserved foods ingest. In conclusion the CChM diagnosis has high frequency in seropositive individuals in Barinas and heart failure prevention must be based on an early medical attention and educative strategies in order to control risk factors. PMID:24974628

  16. Effects of omega-3 polyunsaturated fatty acid supplementation in patients with chronic chagasic cardiomyopathy: study protocol for a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Chronic chagasic cardiomyopathy is an inflammatory disease that occurs in approximately 30% of patients infected by the protozoan Trypanosoma cruzi, and it has a profile of high morbidity and mortality. The worst prognosis and the progression of this cardiomyopathy are associated with an exacerbated immune response and the production of proinflammatory cytokines, which also occur in other cardiomyopathies. Some nutrients, including omega-3 polyunsaturated fatty acids (PUFAs), promote the inhibition and/or stimulation of cytokine production. The objective of this trial is to study the effects of omega-3 PUFA supplementation on the inflammatory response and lipid profile in patients with chronic chagasic cardiomyopathy. Methods/Design This is a parallel, randomized, placebo-controlled, double-blind clinical trial with 40 patients that will be conducted at a reference unit for Chagas disease patients, where the patients will be selected. The study will include patients with chronic chagasic cardiomyopathy who are 18 years of age or older. The exclusion criteria are (a) ongoing diarrheal disease, (b) inflammatory bowel disease, (c) diabetes or other endocrine disease, (d) use of fibrates, niacin, or statins, (e) use of anti-inflammatory drugs, (f) pregnant and lactating women, (g) use of vitamin, mineral, or omega-3 supplementation during the previous 30 days, (h) hospital admission during the study, and (i) other associated cardiomyopathies. The intervention will be treatment with omega-3 PUFAs at a dose of 3 g/day for 8 weeks, compared to placebo (corn oil). The primary endpoints will be the concentrations of inflammatory markers (interleukin (IL)-1, IL-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)α, interferon (IFN)γ, and transforming growth factor (TGF)β). Secondary endpoints will be the fasting glucose, lipid, and anthropometric profiles. For statistical analysis, we plan to run either a t test or Wilcoxon test (numerical variables) and

  17. Evaluation of VDR gene polymorphisms in Trypanosoma cruzi infection and chronic Chagasic cardiomyopathy

    PubMed Central

    Leon Rodriguez, Daniel A; Carmona, F David; González, Clara Isabel; Martin, Javier

    2016-01-01

    Vitamin D is an important modulator of the immune response. It acts over several immune cell types where the Vitamin D receptor (VDR) is expressed. Due to the high relevance of this signaling pathway, several studies have investigated the possible influence of genes involved in the metabolism of Vitamin D and its receptor in different human diseases. Here, we analyzed whether four single-nucleotide polymorphisms of the VDR gene (rs731236, rs7975232, rs1544410 and rs2228570) are involved in the susceptibility to infection by Trypanosoma cruzi and/or to chronic Chagas cardiomyopathy (CCC) in a Colombian endemic population for this parasite. Our results showed that the rs2228570*A allele is associated with CCC development (P = 4.46E−03, OR = 1.51). In summary, the data presented in this report suggest that variation within the VDR gene may affect the immune response against T. cruzi, increasing the probability of cardiac complications in infected individuals. PMID:27502545

  18. Evaluation of VDR gene polymorphisms in Trypanosoma cruzi infection and chronic Chagasic cardiomyopathy.

    PubMed

    Leon Rodriguez, Daniel A; Carmona, F David; González, Clara Isabel; Martin, Javier

    2016-01-01

    Vitamin D is an important modulator of the immune response. It acts over several immune cell types where the Vitamin D receptor (VDR) is expressed. Due to the high relevance of this signaling pathway, several studies have investigated the possible influence of genes involved in the metabolism of Vitamin D and its receptor in different human diseases. Here, we analyzed whether four single-nucleotide polymorphisms of the VDR gene (rs731236, rs7975232, rs1544410 and rs2228570) are involved in the susceptibility to infection by Trypanosoma cruzi and/or to chronic Chagas cardiomyopathy (CCC) in a Colombian endemic population for this parasite. Our results showed that the rs2228570*A allele is associated with CCC development (P = 4.46E-03, OR = 1.51). In summary, the data presented in this report suggest that variation within the VDR gene may affect the immune response against T. cruzi, increasing the probability of cardiac complications in infected individuals. PMID:27502545

  19. Sera of chagasic patients react with antigens from the tomato parasite Phytomonas serpens.

    PubMed

    Graça-de Souza, Viviane K; Monteiro-Góes, Viviane; Manque, Patrício; Souza, Tatiana A C B; Corrêa, Paulo R C; Buck, Gregory A; Ávila, Andréa R; Yamauchi, Lucy M; Pinge-Filho, Phileno; Goldenberg, Samuel; Krieger, Marco A; Yamada-Ogatta, Sueli F

    2010-01-01

    The genus Phytomonas comprises trypanosomatids that can parasitize a broad range of plant species. These flagellates can cause diseases in some plant families with a wide geographic distribution, which can result in great economic losses. We have demonstrated previously that Phytomonas serpens 15T, a tomato trypanosomatid, shares antigens with Trypanosoma cruzi, the agent of human Chagas disease. Herein, two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) were used to identify proteins of P. serpens 15T that are recognized by sera from patients with Chagas disease. After 2D-electrophoresis of whole-cell lysates, 31 peptides were selected and analyzed by tandem mass spectrometry. Twenty-eight polypeptides were identified, resulting in 22 different putative proteins. The identified proteins were classified into 8 groups according to biological process, most of which were clustered into a cellular metabolic process category. These results generated a collection of proteins that can provide a starting point to obtain insights into antigenic cross reactivity among trypanosomatids and to explore P. serpens antigens as candidates for vaccine and immunologic diagnosis studies. PMID:21031268

  20. Bromodichloromethane inhibits human placental trophoblast differentiation.

    PubMed

    Chen, Jiangang; Thirkill, Twanda L; Lohstroh, Peter N; Bielmeier, Susan R; Narotsky, Michael G; Best, Deborah S; Harrison, Randy A; Natarajan, Kala; Pegram, Rex A; Overstreet, James W; Lasley, Bill L; Douglas, Gordon C

    2004-03-01

    Epidemiological data suggest an association between exposures to bromodichloromethane (BDCM), a trihalomethane found in drinking water as a result of drinking water disinfection, and an increased risk of spontaneous abortion. We previously hypothesized that BDCM targets the placenta and showed that the secretion of chorionic gonadotrophin (CG) was reduced in primary cultures of human term syncytiotrophoblasts exposed to BDCM. In the present study we extend this observation by evaluating the effects of BDCM on the morphological differentiation of mononucleated cytotrophoblast cells to multinucleated syncytiotrophoblast-like colonies. Addition of BDCM to cytotrophoblast cultures inhibited the subsequent formation of multinucleated colonies in a dose-dependent manner, as determined by immunocytochemical staining for desmosomes and nuclei. The effect was seen at BDCM concentrations between 0.02 and 2 mM and was confirmed by quantitative image analysis. Secretion of bioactive and immunoreactive chorionic gonadotropin was also significantly inhibited in a dose-dependent manner under these culture conditions, and cellular levels of CG were also reduced. Trophoblast viability was not compromised by exposure to BDCM. We conclude that BDCM disrupts syncytiotrophoblast formation and inhibits CG secretion in vitro. Although other tissue targets are not ruled out, these data substantiate the idea that BDCM targets the placenta and could have implications for understanding the adverse pregnancy outcomes associated with BDCM exposure in humans. PMID:14691210

  1. Autophagy in Normal and Abnormal Early Human Pregnancies.

    PubMed

    Avagliano, Laura; Terraneo, Laura; Virgili, Eleonora; Martinelli, Carla; Doi, Patrizia; Samaja, Michele; Bulfamante, Gaetano Pietro; Marconi, Anna Maria

    2015-07-01

    Autophagy is an inducible catabolic process by which cells degrade and recycle materials to survive stress, starvation, and hypoxia. The aim of this study was to evaluate autophagy at the fetal-maternal interface, to assess autophagy involvement during the early phase of human gestation, and to explore autophagic modification in case of early abnormal pregnancy outcome. Specimens were collected from first-trimester normal gestations undergoing legal termination of pregnancy and first-trimester sporadic spontaneous miscarriages. Autophagy was studied in villous and decidual samples by transmission electron microscopy, immunohistochemistry, immunofluorescence, and Western blotting. Autophagy markers were found in cytotrophoblast, syncytiotrophoblast, extravillous trophoblast, and decidual stromal cells. Autophagy is physiologically involved in early normal gestation. Compared with normal pregnancy, spontaneous miscarriage presents an increase in autophagy expression in villous specimens due to an increment in concentration of autophagic vacuole in syncytiotrophoblast, suggesting a cytoprotective mechanism of the cells to respond to microenvironmental challenge. PMID:25544676

  2. Low Frequency of Circulating CD8+ T Stem Cell Memory Cells in Chronic Chagasic Patients with Severe Forms of the Disease

    PubMed Central

    Mateus, Jose; Lasso, Paola; Pavia, Paula; Rosas, Fernando; Roa, Nubia; Valencia-Hernández, Carlos Andrés; González, John Mario; Puerta, Concepción J.; Cuéllar, Adriana

    2015-01-01

    Background CD8+ T cells have been shown to play a crucial role in Trypanosoma cruzi infection. Memory CD8+ T cells can be categorised based on their distinct differentiation stages and functional activities as follows: stem cell memory (TSCM), central memory (TCM), transitional memory (TTM), effector memory (TEM) and terminal effector (TTE) cells. Currently, the immune mechanisms that control T. cruzi in the chronic phase of the infection are unknown. Methodology/Principal Findings To characterise the CD8+ T cell subsets that could be participating in the control of T. cruzi infection, in this study, we compared total and T. cruzi-specific circulating CD8+ T cells with distinctive phenotypic and functional features in chronic chagasic patients (CCPs) with different degrees of cardiac dysfunction. We observed a decreased frequency of total TSCM along with an increased frequency of TTE in CCPs with severe disease. Antigen-specific TSCM cells were not detectable in CCPs with severe forms of the disease. A functional profile of CD8+ T cell subsets among CCPs revealed a high frequency of monofunctional CD8+ T cells in the most severe patients with IFN-γ+- or TNF-α+-producing cells. Conclusions/Significance These findings suggest that CD8+ TSCM cells may be associated with the immune response to T. cruzi and outcome of Chagas disease, given that these cells may be involved in repopulating the T cell pool that controls infection. PMID:25569149

  3. Mechanisms of alphafetoprotein transfer in the perfused human placental cotyledon from uncomplicated pregnancy.

    PubMed Central

    Brownbill, P; Edwards, D; Jones, C; Mahendran, D; Owen, D; Sibley, C; Johnson, R; Swanson, P; Nelson, D M

    1995-01-01

    We investigated the mechanisms of alphafetoprotein (AFP) transfer across the human placenta by correlating measurements of AFP transfer with cytochemical localization of AFP. Placental cotyledons were dually perfused in vitro with either the fetal or maternal perfusate containing umbilical cord plasma as a source of AFP. Steady state AFP clearance, corrected for release of endogenous AFP, was 0.973 +/- 0.292 microliter/min per gram in the fetal to maternal direction (n = 10), significantly higher (P < 0.02) than that in the maternal to fetal direction (n = 5; 0.022 +/- 0.013 microliter/min per gram). Clearance of a similarly sized protein, horseradish peroxidase was also asymmetric but clearance of the small tracer creatinine was not. Using a monoclonal antibody, we localized AFP to fibrinoid deposits in regions of villi with discontinuities of the syncytiotrophoblast, to cytotrophoblast cells in these deposits, to syncytiotrophoblast on some villi, and to trophoblast cells in the decidua. We conclude that AFP transfer in the placenta is asymmetric and that there are two available pathways for AFP transfer: (a) from the fetal circulation into the villous core and across fibrinoid deposits at discontinuities in the villous syncytiotrophoblast to enter the maternal circulation; and (b) AFP present in the decidua could enter vessels that traverse the basal plate. Images PMID:7593608

  4. Human Leucocyte Antigen-G (HLA-G) and Its Murine Functional Homolog Qa2 in the Trypanosoma cruzi Infection

    PubMed Central

    Dias, Fabrício C.; Mendes-Junior, Celso T.; Silva, Maria C.; Tristão, Fabrine S. M.; Dellalibera-Joviliano, Renata; Soares, Edson G.; Menezes, Jean G.; Schmidt, André; Dantas, Roberto O.; Marin-Neto, José A.; Silva, João S.; Donadi, Eduardo A.

    2015-01-01

    Genetic susceptibility factors, parasite strain, and an adequate modulation of the immune system seem to be crucial for disease progression after Trypanosoma cruzi infection. HLA-G and its murine functional homolog Qa2 have well-recognized immunomodulatory properties. We evaluated the HLA-G 3′ untranslated region (3′UTR) polymorphic sites (associated with mRNA stability and target for microRNA binding) and HLA-G tissue expression (heart, colon, and esophagus) in patients presenting Chagas disease, stratified according to the major clinical variants. Further, we investigated the transcriptional levels of Qa2 and other pro- and anti-inflammatory genes in affected mouse tissues during T. cruzi experimental acute and early chronic infection induced by the CL strain. Chagas disease patients exhibited differential HLA-G 3′UTR susceptibility allele/genotype/haplotype patterns, according to the major clinical variant (digestive/cardiac/mixed/indeterminate). HLA-G constitutive expression on cardiac muscle and colonic cells was decreased in Chagasic tissues; however, no difference was observed for Chagasic and non-Chagasic esophagus tissues. The transcriptional levels of Qa2 and other anti and proinflammatory (CTLA-4, PDCD1, IL-10, INF-γ, and NOS-2) genes were induced only during the acute T. cruzi infection in BALB/c and C57BL/6 mice. We present several lines of evidence indicating the role of immunomodulatory genes and molecules in human and experimental T. cruzi infection. PMID:25688175

  5. Roles of CDX2 and EOMES in human induced trophoblast progenitor cells

    SciTech Connect

    Chen, Ying; Wang, Kai; Gong, Yun Guo; Khoo, Sok Kean; Leach, Richard

    2013-02-08

    Highlights: ► CDX2 and EOMES play critical roles in human induced trophoblast progenitors (iTP). ► iTP cells directly transformed from fibroblasts. ► Differentiation of iTP cells into extravillous trophoblasts and syncytiotrophoblasts. -- Abstract: Abnormal trophoblast lineage proliferation and differentiation in early pregnancy have been associated with the pathogenesis of placenta diseases of pregnancy. However, there is still a gap in understanding the molecular mechanisms of early placental development due to the limited primary trophoblast cultures and fidelity of immortalized trophoblast lines. Trophoblasts stem (TS) cells, an in vitro model of trophectoderm that can differentiate into syncytiotrophoblasts and extravillous trophoblasts, can be an attractive tool for early pregnancy research. TS cells are well established in mouse but not in humans due to insufficient knowledge of which trophoblast lineage-specific transcription factors are involved in human trophectoderm (TE) proliferation and differentiation. Here, we applied induced pluripotent stem cell technique to investigate the human trophoblast lineage-specific transcription factors. We established human induced trophoblast progenitor (iTP) cells by direct reprogramming the fibroblasts with a pool of mouse trophoblast lineage-specific transcription factors consisting of CDX2, EOMES, and ELF5. The human iTP cells exhibit epithelial morphology and can be maintained in vitro for more than 2 months. Gene expression profile of these cells was tightly clustered with human trophectoderm but not with human neuron progenitor cells, mesenchymal stem cells, or endoderm cells. These cells are capable of differentiating into cells with an invasive capacity, suggesting extravillous trophoblasts. They also form multi-nucleated cells which secrete human chorionic gonadotropin and estradiol, consistent with a syncytiotrophoblast phenotype. Our results provide the evidence that transcription factors CDX2 and

  6. Trypanosoma cruzi invades host cells through the activation of endothelin and bradykinin receptors: a converging pathway leading to chagasic vasculopathy

    PubMed Central

    Andrade, Daniele; Serra, Rafaela; Svensjö, Erik; Lima, Ana Paula C; Ramos Junior, Erivan S; Fortes, Fabio S; Morandini, Ana Carolina F; Morandi, Verônica; Soeiro, Maria de N; Tanowitz, Herbert B; Scharfstein, Julio

    2012-01-01

    BACKGROUND AND PURPOSE Independent studies in experimental models of Trypanosoma cruzi appointed different roles for endothelin-1 (ET-1) and bradykinin (BK) in the immunopathogenesis of Chagas disease. Here, we addressed the hypothesis that pathogenic outcome is influenced by functional interplay between endothelin receptors (ETAR and ETBR) and bradykinin B2 receptors (B2R). EXPERIMENTAL APPROACH Intravital microscopy was used to determine whether ETR/B2R drives the accumulation of rhodamine-labelled leucocytes in the hamster cheek pouch (HCP). Inflammatory oedema was measured in the infected BALB/c paw of mice. Parasite invasion was assessed in CHO over-expressing ETRs, mouse cardiomyocytes, endothelium (human umbilical vein endothelial cells) or smooth muscle cells (HSMCs), in the presence/absence of antagonists of B2R (HOE-140), ETAR (BQ-123) and ETBR (BQ-788), specific IgG antibodies to each GPCRs; cholesterol or calcium-depleting drugs. RNA interference (ETAR or ETBR genes) in parasite infectivity was investigated in HSMCs. KEY RESULTS BQ-123, BQ-788 and HOE-140 reduced leucocyte accumulation in HCP topically exposed to trypomastigotes and blocked inflammatory oedema in infected mice. Acting synergistically, ETAR and ETBR antagonists reduced parasite invasion of HSMCs to the same extent as HOE-140. Exogenous ET-1 potentiated T. cruzi uptake by HSMCs via ETRs/B2R, whereas RNA interference of ETAR and ETBR genes conversely reduced parasite internalization. ETRs/B2R-driven infection in HSMCs was reduced in HSMC pretreated with methyl-β-cyclodextrin, a cholesterol-depleting drug, or in thapsigargin- or verapamil-treated target cells. CONCLUSIONS AND IMPLICATIONS Our findings suggest that plasma leakage, a neutrophil-driven inflammatory response evoked by trypomastigotes via the kinin/endothelin pathways, may offer a window of opportunity for enhanced parasite invasion of cardiovascular cells. LINKED ARTICLE This paper is commented on by D'Orléans-Juste et al

  7. Store-operated Ca2+ entry in first trimester and term human placenta.

    PubMed

    Clarson, L H; Roberts, V H J; Hamark, B; Elliott, A C; Powell, T

    2003-07-15

    We have examined whether store-operated Ca2+ entry, a common pathway for Ca2+ entry in non-excitable tissue, is apparent in the syncytiotrophoblast of both first trimester and term human placenta. Expression of transient receptor potential (TRPC) homologues, a family of channels thought to be involved in store-operated Ca2+ entry, was also studied at the mRNA and protein levels. [Ca2+]i in syncytiotrophoblast of first trimester and term placental villous fragments was measured by microfluorimetry using the Ca2+-sensitive dye fura-2. Store-operated Ca2+ entry was stimulated using 1 microM thapsigargin in Ca(2+)-free Tyrode buffer (no added Ca2+ + 1 mM EGTA) followed by superfusion with control (Ca2+-containing) buffer. In term fragments, this protocol resulted in a rapid increase in [Ca2+]i, which was inhibited in the presence of 150 microM GdCl3, 200 microM NiCl2, 200 microM CoCl2 or 30 microM SKF96365 but was unaffected by addition of 10 microM nifedipine. It was not possible to stimulate such a rise in [Ca2+]i in first trimester fragments. Messenger RNA encoding TRPC1, TRPC3, TRPC4, TRPC5 and TRPC6 was identified in both first trimester and term placentas. From Western blotting, TRPC3 and TRPC6 proteins were detected in term, but not in first trimester, placentas, while TRPC1 protein was not detected. By immunocytochemistry, TRPC3 and TRPC4 were localised to cytotrophoblast cells in first trimester placentas and to the syncytiotrophoblast in term placentas. TRPC6 staining was present in the syncytiotrophoblast of both first trimester and term placenta, but the intensity was much greater in the latter. We propose that store-operated Ca2+ entry may be an important route for Ca2+ entry into the syncytiotrophoblast of term, but not first trimester placentas, and that in human placenta TRPC channels may underlie this entry mechanism. PMID:12766233

  8. Oxygen-Sensitive K+ Channels Modulate Human Chorionic Gonadotropin Secretion from Human Placental Trophoblast.

    PubMed

    Díaz, Paula; Sibley, Colin P; Greenwood, Susan L

    2016-01-01

    Human chorionic gonadotropin (hCG) is a key autocrine/paracrine regulator of placental syncytiotrophoblast, the transport epithelium of the human placenta. Syncytiotrophoblast hCG secretion is modulated by the partial pressure of oxygen (pO2), reactive oxygen species (ROS) and potassium (K+) channels. Here we test the hypothesis that K+ channels mediate the effects of pO2 and ROS on hCG secretion. Placental villous explants from normal term pregnancies were cultured for 6 days at 6% (normoxia), 21% (hyperoxia) or 1% (hypoxia) pO2. On days 3-5, explants were treated with 5mM 4-aminopyridine (4-AP) or tetraethylammonium (TEA), blockers of pO2-sensitive voltage-gated K+ (KV) channels, or ROS (10-1000μM H2O2). hCG secretion and lactate dehydrogenase (LDH) release, a marker of necrosis, were determined daily. At day 6, hCG and LDH were measured in tissue lysate and 86Rb (K+) efflux assessed to estimate syncytiotrophoblast K+ permeability. hCG secretion and 86Rb efflux were significantly greater in explants maintained in 21% pO2 than normoxia. 4-AP/TEA inhibited hCG secretion to a greater extent at 21% than 6% and 1% pO2, and reduced 86Rb efflux at 21% but not 6% pO2. LDH release and tissue LDH/hCG were similar in 6%, 21% and 1% pO2 and unaffected by 4-AP/TEA. H2O2 stimulated 86Rb efflux and hCG secretion at normoxia but decreased 86Rb efflux, without affecting hCG secretion, at 21% pO2. 4-AP/TEA-sensitive K+ channels participate in pO2-sensitive hCG secretion from syncytiotrophoblast. ROS effects on both hCG secretion and 86Rb efflux are pO2-dependent but causal links between the two remain to be established. PMID:26863525

  9. Oxygen-Sensitive K+ Channels Modulate Human Chorionic Gonadotropin Secretion from Human Placental Trophoblast

    PubMed Central

    Díaz, Paula; Sibley, Colin P.; Greenwood, Susan L.

    2016-01-01

    Human chorionic gonadotropin (hCG) is a key autocrine/paracrine regulator of placental syncytiotrophoblast, the transport epithelium of the human placenta. Syncytiotrophoblast hCG secretion is modulated by the partial pressure of oxygen (pO2), reactive oxygen species (ROS) and potassium (K+) channels. Here we test the hypothesis that K+ channels mediate the effects of pO2 and ROS on hCG secretion. Placental villous explants from normal term pregnancies were cultured for 6 days at 6% (normoxia), 21% (hyperoxia) or 1% (hypoxia) pO2. On days 3–5, explants were treated with 5mM 4-aminopyridine (4-AP) or tetraethylammonium (TEA), blockers of pO2-sensitive voltage-gated K+ (KV) channels, or ROS (10–1000μM H2O2). hCG secretion and lactate dehydrogenase (LDH) release, a marker of necrosis, were determined daily. At day 6, hCG and LDH were measured in tissue lysate and 86Rb (K+) efflux assessed to estimate syncytiotrophoblast K+ permeability. hCG secretion and 86Rb efflux were significantly greater in explants maintained in 21% pO2 than normoxia. 4-AP/TEA inhibited hCG secretion to a greater extent at 21% than 6% and 1% pO2, and reduced 86Rb efflux at 21% but not 6% pO2. LDH release and tissue LDH/hCG were similar in 6%, 21% and 1% pO2 and unaffected by 4-AP/TEA. H2O2 stimulated 86Rb efflux and hCG secretion at normoxia but decreased 86Rb efflux, without affecting hCG secretion, at 21% pO2. 4-AP/TEA-sensitive K+ channels participate in pO2-sensitive hCG secretion from syncytiotrophoblast. ROS effects on both hCG secretion and 86Rb efflux are pO2-dependent but causal links between the two remain to be established. PMID:26863525

  10. D21S418E identifies a cAMP-regulated gene located on chromosome 21q22. 3 that is expressed in placental syncytiotrophoblast and choriocarcinoma cells

    SciTech Connect

    Kido, S.; Sakuragi, N.; Bronner, M.P.; Sayegh, R.; Strauss, J.F. III ); Berger, R.; Patterson, D. )

    1993-07-01

    A partial cDNA (D21S418E) whose nucleotide sequence has no significant homologies with known mammalian DNA sequences was isolated from a human placental library. The cDNA hybridized with a 10-kb transcript present in term placenta. Messages of 10 and 7.5 kb were induced in BeWo and JEG-3 choriocarcinoma cells by treatment with 8-Br-cAMP. The mRNA was not detected in human brain, liver, lung, kidney, pancreas, heart, skeletal muscle, or myometrium. The D21S418E locus was assigned to a 3.5-Mb region of chromosome 21q22.3. 15 refs., 2 figs., 1 tab.

  11. Localization of IL-4 and IL-4 receptors in the human term placenta, decidua and amniochorionic membranes.

    PubMed Central

    de Moraes-Pinto, M I; Vince, G S; Flanagan, B F; Hart, C A; Johnson, P M

    1997-01-01

    There has been much recent interest in cytokine expression at the materno-fetal interface. Although T-helper 2 (Th2)-type cytokines have been described in the murine feto-placental unit, few studies have as yet been performed in human pregnancy. We have examined the production of interleukin-4 (IL-4) and expression of IL-4 receptors in the human term placenta, decidua and amniochorionic membranes. Immunohistochemical analyses revealed that cytotrophoblast, decidual macrophages and both maternal and fetal endothelial cells consistently expressed IL-4, whereas syncytiotrophoblast and placental macrophages showed an inconsistent pattern between specimens. High- and low-affinity IL-4 receptors were demonstrated by immunohistochemistry at the same cellular sites as stained for IL-4, and detection of IL-4 receptors was also variable in syncytiotrophoblast. Reverse-transcribed-polymerase chain reaction (RT-PCR) analysis showed that both IL-4 and its alternative splice variant, IL-482, are produced both in placental villi and in amniochorionic and decidual tissue. Ligand-binding assays identified the presence, on isolated term syncytiotrophoblast microvillous plasma membrane vesicle preparations, of functional high-affinity binding sites for IL-4 with a Kd in the range 102-112 pM and an apparent receptor density in the range 99-102 x 10(8) sites/mg protein. Three human choriocarcinoma (BeWo, JEG-3 and Jar) and one amnion-derived (AV3) cell lines expressed IL-4 and both high- and low-affinity IL-4 receptors. The constitutive expression of both IL-4 and IL-4 receptors, together with the novel finding of the alternative splice variant IL-482 in the immediate tissues at the materno fetal interface suggest an immunobiological role for IL-4 in human pregnancy. Images Figure 1 Figure 2 Figure 3 PMID:9038717

  12. Early Regulation of Profibrotic Genes in Primary Human Cardiac Myocytes by Trypanosoma cruzi

    PubMed Central

    Dykan, Andrey; Rachakonda, Girish; Villalta, Fernando; Mandape, Sammed N.; Lima, Maria F.; Pratap, Siddharth; Nde, Pius N.

    2016-01-01

    The molecular mechanisms of Trypanosoma cruzi induced cardiac fibrosis remains to be elucidated. Primary human cardiomyoctes (PHCM) exposed to invasive T. cruzi trypomastigotes were used for transcriptome profiling and downstream bioinformatic analysis to determine fibrotic-associated genes regulated early during infection process (0 to 120 minutes). The identification of early molecular host responses to T. cruzi infection can be exploited to delineate important molecular signatures that can be used for the classification of Chagasic patients at risk of developing heart disease. Our results show distinct gene network architecture with multiple gene networks modulated by the parasite with an incline towards progression to a fibrogenic phenotype. Early during infection, T. cruzi significantly upregulated transcription factors including activator protein 1 (AP1) transcription factor network components (including FOSB, FOS and JUNB), early growth response proteins 1 and 3 (EGR1, EGR3), and cytokines/chemokines (IL5, IL6, IL13, CCL11), which have all been implicated in the onset of fibrosis. The changes in our selected genes of interest did not all start at the same time point. The transcriptome microarray data, validated by quantitative Real-Time PCR, was also confirmed by immunoblotting and customized Enzyme Linked Immunosorbent Assays (ELISA) array showing significant increases in the protein expression levels of fibrogenic EGR1, SNAI1 and IL 6. Furthermore, phosphorylated SMAD2/3 which induces a fibrogenic phenotype is also upregulated accompanied by an increased nuclear translocation of JunB. Pathway analysis of the validated genes and phospho-proteins regulated by the parasite provides the very early fibrotic interactome operating when T. cruzi comes in contact with PHCM. The interactome architecture shows that the parasite induces both TGF-β dependent and independent fibrotic pathways, providing an early molecular foundation for Chagasic cardiomyopathy

  13. Early Regulation of Profibrotic Genes in Primary Human Cardiac Myocytes by Trypanosoma cruzi.

    PubMed

    Udoko, Aniekanabassi N; Johnson, Candice A; Dykan, Andrey; Rachakonda, Girish; Villalta, Fernando; Mandape, Sammed N; Lima, Maria F; Pratap, Siddharth; Nde, Pius N

    2016-01-01

    The molecular mechanisms of Trypanosoma cruzi induced cardiac fibrosis remains to be elucidated. Primary human cardiomyoctes (PHCM) exposed to invasive T. cruzi trypomastigotes were used for transcriptome profiling and downstream bioinformatic analysis to determine fibrotic-associated genes regulated early during infection process (0 to 120 minutes). The identification of early molecular host responses to T. cruzi infection can be exploited to delineate important molecular signatures that can be used for the classification of Chagasic patients at risk of developing heart disease. Our results show distinct gene network architecture with multiple gene networks modulated by the parasite with an incline towards progression to a fibrogenic phenotype. Early during infection, T. cruzi significantly upregulated transcription factors including activator protein 1 (AP1) transcription factor network components (including FOSB, FOS and JUNB), early growth response proteins 1 and 3 (EGR1, EGR3), and cytokines/chemokines (IL5, IL6, IL13, CCL11), which have all been implicated in the onset of fibrosis. The changes in our selected genes of interest did not all start at the same time point. The transcriptome microarray data, validated by quantitative Real-Time PCR, was also confirmed by immunoblotting and customized Enzyme Linked Immunosorbent Assays (ELISA) array showing significant increases in the protein expression levels of fibrogenic EGR1, SNAI1 and IL 6. Furthermore, phosphorylated SMAD2/3 which induces a fibrogenic phenotype is also upregulated accompanied by an increased nuclear translocation of JunB. Pathway analysis of the validated genes and phospho-proteins regulated by the parasite provides the very early fibrotic interactome operating when T. cruzi comes in contact with PHCM. The interactome architecture shows that the parasite induces both TGF-β dependent and independent fibrotic pathways, providing an early molecular foundation for Chagasic cardiomyopathy

  14. Intracellular and extracellular pH dynamics in the human placenta from diabetes mellitus.

    PubMed

    Araos, Joaquín; Silva, Luis; Salsoso, Rocío; Sáez, Tamara; Barros, Eric; Toledo, Fernando; Gutiérrez, Jaime; Pardo, Fabián; Leiva, Andrea; Sanhueza, Carlos; Sobrevia, Luis

    2016-07-01

    The placenta is a vital organ whose function in diseases of pregnancy is altered, resulting in an abnormal supply of nutrients to the foetus. The lack of placental vasculature homeostasis regulation causes endothelial dysfunction and altered vascular reactivity. The proper distribution of acid- (protons (H(+))) and base-equivalents through the placenta is essential to achieve physiological homeostasis. Several membrane transport mechanisms that control H(+) distribution between the extracellular and intracellular spaces are expressed in the human placenta vascular endothelium and syncytiotrophoblast, including sodium (Na(+))/H(+) exchangers (NHEs). One member of the NHEs family is NHE isoform 1 (NHE1), whose activity results in an alkaline intracellular pH (high intracellular pH (pHi)) and an acidic extracellular pH (pHo). Increased NHE1 expression, maximal transport activity, and turnover are reported in human syncytiotrophoblasts and lymphocytes from patients with diabetes mellitus type I (DMT1), and a positive correlation between NHEs activity and plasma factors, such as that between thrombin and platelet factor 3, has been reported in diabetes mellitus type II (DMT2). However, gestational diabetes mellitus (GDM) could result in a higher sensitivity of the human placenta to acidic pHo. We summarized the findings on pHi and pHo modulation in the human placenta with an emphasis on pregnancies in which the mother diagnosed with diabetes mellitus. A potential role of NHEs, particularly NHE1, is proposed regarding placental dysfunction in DMT1, DMT2, and GDM. PMID:27324099

  15. Direct Involvement of HERV-W Env Glycoprotein in Human Trophoblast Cell Fusion and Differentiation

    PubMed Central

    Frendo, Jean-Louis; Olivier, Delphine; Cheynet, Valérie; Blond, Jean-Luc; Bouton, Olivier; Vidaud, Michel; Rabreau, Michèle; Evain-Brion, Danièle; Mallet, François

    2003-01-01

    We recently demonstrated that the product of the HERV-W env gene, a retroviral envelope protein also dubbed syncytin, is a highly fusogenic membrane glycoprotein inducing the formation of syncytia on interaction with the type D mammalian retrovirus receptor. In addition, the detection of HERV-W Env protein (Env-W) expression in placental tissue sections led us to propose a role for this fusogenic glycoprotein in placenta formation. To evaluate this hypothesis, we analyzed the involvement of Env-W in the differentiation of primary cultures of human villous cytotrophoblasts that spontaneously differentiate by cell fusion into syncytiotrophoblasts in vitro. First, we observed that HERV-W env mRNA and glycoprotein expression are colinear with primary cytotrophoblast differentiation and with expression of human chorionic gonadotropin (hCG), a marker of syncytiotrophoblast formation. Second, we observed that in vitro stimulation of trophoblast cell fusion and differentiation by cyclic AMP is also associated with a concomitant increase in HERV-W env and hCG mRNA and protein expression. Finally, by using specific antisense oligonucleotides, we demonstrated that inhibition of Env-W protein expression leads to a decrease of trophoblast fusion and differentiation, with the secretion of hCG in culture medium of antisense oligonucleotide-treated cells being decreased by fivefold. Taken together, these results strongly support a direct role for Env-W in human trophoblast cell fusion and differentiation. PMID:12724415

  16. Estrogen-related receptor gamma (ERRgamma) mediates oxygen-dependent induction of aromatase (CYP19) gene expression during human trophoblast differentiation.

    PubMed

    Kumar, Premlata; Mendelson, Carole R

    2011-09-01

    Differentiation of human cytotrophoblasts to syncytiotrophoblast and the associated induction of aromatase/hCYP19 gene expression are dependent upon a critical O(2) tension; however, the underlying molecular mechanisms remain undefined. In this study, we provide compelling evidence that expression of the orphan nuclear receptor, estrogen-related receptor γ (ERRγ), is also O(2) dependent, induced during human syncytiotrophoblast differentiation, and plays an obligatory role in the induction of placenta-specific hCYP19I.1 gene expression. Treatment with the selective ERRγ agonist, DY131, or overexpression of ERRγ, stimulated hCYP19 expression in syncytiotrophoblast. Overexpression of ERRγ prevented effects of hypoxia to repress hCYP19 gene expression in cultured trophoblasts. Conversely, small interfering RNA-mediated knockdown of endogenous ERRγ in primary trophoblasts markedly inhibited hCYP19 expression. Promoter and site-directed mutagenesis studies in transfected placental cells identified a nuclear receptor element within placenta-specific hCYP19 promoter I.1 required for ERRγ-stimulated activity. Recruitment of endogenous ERRγ to the nuclear receptor element region in hCYP19 promoter during trophoblast differentiation, assessed by chromatin immunoprecipitation, was prevented by hypoxia. Deferoxamine-induced hypoxia-inducible factor-1α (HIF-1α) levels decreased ERRγ expression, whereas knockdown of endogenous HIF-1α prevented ERRγ suppression by hypoxia. Chromatin immunoprecipitation analysis of trophoblasts cultured in hypoxia revealed recruitment of HIF-1α to one of two putative hypoxia response elements in the ERRγ promoter, providing in vivo evidence of a direct HIF-1α involvement in ERRγ expression. Collectively, these novel findings identify ERRγ as an O(2)-dependent transcription factor and HIF-1α target gene that serves a critical role in the induction of hCYP19 expression during human trophoblast differentiation. PMID:21757507

  17. Estrogen-Related Receptor γ (ERRγ) Mediates Oxygen-Dependent Induction of Aromatase (CYP19) Gene Expression during Human Trophoblast Differentiation

    PubMed Central

    Kumar, Premlata

    2011-01-01

    Differentiation of human cytotrophoblasts to syncytiotrophoblast and the associated induction of aromatase/hCYP19 gene expression are dependent upon a critical O2 tension; however, the underlying molecular mechanisms remain undefined. In this study, we provide compelling evidence that expression of the orphan nuclear receptor, estrogen-related receptor γ (ERRγ), is also O2 dependent, induced during human syncytiotrophoblast differentiation, and plays an obligatory role in the induction of placenta-specific hCYP19I.1 gene expression. Treatment with the selective ERRγ agonist, DY131, or overexpression of ERRγ, stimulated hCYP19 expression in syncytiotrophoblast. Overexpression of ERRγ prevented effects of hypoxia to repress hCYP19 gene expression in cultured trophoblasts. Conversely, small interfering RNA-mediated knockdown of endogenous ERRγ in primary trophoblasts markedly inhibited hCYP19 expression. Promoter and site-directed mutagenesis studies in transfected placental cells identified a nuclear receptor element within placenta-specific hCYP19 promoter I.1 required for ERRγ-stimulated activity. Recruitment of endogenous ERRγ to the nuclear receptor element region in hCYP19 promoter during trophoblast differentiation, assessed by chromatin immunoprecipitation, was prevented by hypoxia. Deferoxamine-induced hypoxia-inducible factor-1α (HIF-1α) levels decreased ERRγ expression, whereas knockdown of endogenous HIF-1α prevented ERRγ suppression by hypoxia. Chromatin immunoprecipitation analysis of trophoblasts cultured in hypoxia revealed recruitment of HIF-1α to one of two putative hypoxia response elements in the ERRγ promoter, providing in vivo evidence of a direct HIF-1α involvement in ERRγ expression. Collectively, these novel findings identify ERRγ as an O2-dependent transcription factor and HIF-1α target gene that serves a critical role in the induction of hCYP19 expression during human trophoblast differentiation. PMID:21757507

  18. Killing of human tumor cells in culture with adriamycin conjugates of human transferrin

    SciTech Connect

    Yeh, C.J.; Faulk, W.P.

    1984-07-01

    Receptors for human transferrin (Trf) in high density are found on reticulocytes and syncytiotrophoblast, but most unstimulated, normal adult cells do not bind Trf. In contrast, leukemia and breast adenocarcinoma cells have been shown to manifest Trf receptors, raising the possibility that these receptors might be employed to bind cytotoxic Trf conjugates. Trf was conjugated with adriamycin (Adr) and it was shown that the conjugates are bound by Trf receptors on plasma membranes of Daudi and HL-60 cells, following which Adr is identified in the nuclei of these cells. The biological effect of Adr is quantitated by the inhibition of tritiated thymidine uptake, and subsequent cell death is measured by trypan blue exclusion. The killing correlates directly with both the time of exposure and the amount of conjugate employed. These results suggest that such cytotoxic Trf conjugates hold promise for selective in vivo killing of some malignant cells.

  19. Corticotropin-releasing hormone stimulates expression of leptin, 11beta-HSD2 and syncytin-1 in primary human trophoblasts

    PubMed Central

    2012-01-01

    Background The placental syncytiotrophoblast is the major source of maternal plasma corticotropin-releasing hormone (CRH) in the second half of pregnancy. Placental CRH exerts multiple functions in the maternal organism: It induces the adrenal secretion of cortisol via the stimulation of adrenocorticotropic hormone, regulates the timing of birth via its actions in the myometrium and inhibits the invasion of extravillous trophoblast cells in vitro. However, the auto- and paracrine actions of CRH on the syncytiotrophoblast itself are unknown. Intrauterine growth restriction (IUGR) is accompanied by an increase in placental CRH, which could be of pathophysiological relevance for the dysregulation in syncytialisation seen in IUGR placentas. Methods We aimed to determine the effect of CRH on isolated primary trophoblastic cells in vitro. After CRH stimulation the trophoblast syncytialisation rate was monitored via syncytin-1 gene expression and beta-hCG (beta-human chorionic gonadotropine) ELISA in culture supernatant. The expression of the IUGR marker genes leptin and 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2) was measured continuously over a period of 72 h. We hypothesized that CRH might attenuate syncytialisation, induce leptin, and reduce 11beta-HSD2 expression in primary villous trophoblasts, which are known features of IUGR. Results CRH did not influence the differentiation of isolated trophoblasts into functional syncytium as determined by beta-hCG secretion, albeit inducing syncytin-1 expression. Following syncytialisation, CRH treatment significantly increased leptin and 11beta-HSD2 expression, as well as leptin secretion into culture supernatant after 48 h. Conclusion The relevance of CRH for placental physiology is underlined by the present in vitro study. The induction of leptin and 11beta-HSD2 in the syncytiotrophoblast by CRH might promote fetal nutrient supply and placental corticosteroid metabolism in the phase before labour induction. PMID

  20. Human Primary Trophoblast Cell Culture Model to Study the Protective Effects of Melatonin Against Hypoxia/reoxygenation-induced Disruption.

    PubMed

    Sagrillo-Fagundes, Lucas; Clabault, Hélène; Laurent, Laetitia; Hudon-Thibeault, Andrée-Anne; Salustiano, Eugênia Maria Assunção; Fortier, Marlène; Bienvenue-Pariseault, Josianne; Wong Yen, Philippe; Sanderson, J Thomas; Vaillancourt, Cathy

    2016-01-01

    This protocol describes how villous cytotrophoblast cells are isolated from placentas at term by successive enzymatic digestions, followed by density centrifugation, media gradient isolation and immunomagnetic purification. As observed in vivo, mononucleated villous cytotrophoblast cells in primary culture differentiate into multinucleated syncytiotrophoblast cells after 72 hr. Compared to normoxia (8% O2), villous cytotrophoblast cells that undergo hypoxia/reoxygenation (0.5% / 8% O2) undergo increased oxidative stress and intrinsic apoptosis, similar to that observed in vivo in pregnancy complications such as preeclampsia, preterm birth, and intrauterine growth restriction. In this context, primary villous trophoblasts cultured under hypoxia/reoxygenation conditions represent a unique experimental system to better understand the mechanisms and signalling pathways that are altered in human placenta and facilitate the search for effective drugs that protect against certain pregnancy disorders. Human villous trophoblasts produce melatonin and express its synthesizing enzymes and receptors. Melatonin has been suggested as a treatment for preeclampsia and intrauterine growth restriction because of its protective antioxidant effects. In the primary villous cytotrophoblast cell model described in this paper, melatonin has no effect on trophoblast cells in normoxic state but restores the redox balance of syncytiotrophoblast cells disrupted by hypoxia/reoxygenation. Thus, human villous trophoblast cells in primary culture are an excellent approach to study the mechanisms behind the protective effects of melatonin on placental function during hypoxia/reoxygenation. PMID:27500522

  1. Promiscuous Recognition of a Trypanosoma cruzi CD8+ T Cell Epitope among HLA-A2, HLA-A24 and HLA-A1 Supertypes in Chagasic Patients

    PubMed Central

    Guzmán, Fanny; Rosas, Fernando; Thomas, M. Carmen; López, Manuel Carlos; González, John Mario; Cuéllar, Adriana; Puerta, Concepción J.

    2016-01-01

    Background TcTLE is a nonamer peptide from Trypanosoma cruzi KMP-11 protein that is conserved among different parasite strains and that is presented by different HLA-A molecules from the A2 supertype. Because peptides presented by several major histocompatibility complex (MHC) supertypes are potential targets for immunotherapy, the aim of this study was to determine whether MHC molecules other than the A2 supertype present the TcTLE peptide. Methodology/Principal Findings From 36 HLA-A2-negative chagasic patients, the HLA-A genotypes of twenty-eight patients with CD8+ T cells that recognized the TcTLE peptide using tetramer (twenty) or functional (eight) assays, were determined. SSP-PCR was used to identify the A locus and the allelic variants. Flow cytometry was used to analyze the frequency of TcTLE-specific CD8+ T cells, and their functional activity (IFN-γ, TNFα, IL-2, perforin, granzyme and CD107a/b production) was induced by exposure to the TcTLE peptide. All patients tested had TcTLE-specific CD8+ T cells with frequencies ranging from 0.07–0.37%. Interestingly, seven of the twenty-eight patients had HLA-A homozygous alleles: A*24 (5 patients), A*23 (1 patient) and A*01 (1 patient), which belong to the A24 and A1 supertypes. In the remaining 21 patients with HLA-A heterozygous alleles, the most prominent alleles were A24 and A68. The most common allele sub-type was A*2402 (sixteen patients), which belongs to the A24 supertype, followed by A*6802 (six patients) from the A2 supertype. Additionally, the A*3002/A*3201 alleles from the A1 supertype were detected in one patient. All patients presented CD8+ T cells producing at least one cytokine after TcTLE peptide stimulation. Conclusion/Significance These results show that TcTLE is a promiscuous peptide that is presented by the A24 and A1 supertypes, in addition to the A2 supertype, suggesting its potential as a target for immunotherapy. PMID:26974162

  2. Activin/nodal signaling switches the terminal fate of human embryonic stem cell-derived trophoblasts.

    PubMed

    Sarkar, Prasenjit; Randall, Shan M; Collier, Timothy S; Nero, Anthony; Russell, Teal A; Muddiman, David C; Rao, Balaji M

    2015-04-01

    Human embryonic stem cells (hESCs) have been routinely treated with bone morphogenetic protein and/or inhibitors of activin/nodal signaling to obtain cells that express trophoblast markers. Trophoblasts can terminally differentiate to either extravillous trophoblasts or syncytiotrophoblasts. The signaling pathways that govern the terminal fate of these trophoblasts are not understood. We show that activin/nodal signaling switches the terminal fate of these hESC-derived trophoblasts. Inhibition of activin/nodal signaling leads to formation of extravillous trophoblast, whereas loss of activin/nodal inhibition leads to the formation of syncytiotrophoblasts. Also, the ability of hESCs to form bona fide trophoblasts has been intensely debated. We have examined hESC-derived trophoblasts in the light of stringent criteria that were proposed recently, such as hypomethylation of the ELF5-2b promoter region and down-regulation of HLA class I antigens. We report that trophoblasts that possess these properties can indeed be obtained from hESCs. PMID:25670856

  3. Activin/Nodal Signaling Switches the Terminal Fate of Human Embryonic Stem Cell-derived Trophoblasts*

    PubMed Central

    Sarkar, Prasenjit; Randall, Shan M.; Collier, Timothy S.; Nero, Anthony; Russell, Teal A.; Muddiman, David C.; Rao, Balaji M.

    2015-01-01

    Human embryonic stem cells (hESCs) have been routinely treated with bone morphogenetic protein and/or inhibitors of activin/nodal signaling to obtain cells that express trophoblast markers. Trophoblasts can terminally differentiate to either extravillous trophoblasts or syncytiotrophoblasts. The signaling pathways that govern the terminal fate of these trophoblasts are not understood. We show that activin/nodal signaling switches the terminal fate of these hESC-derived trophoblasts. Inhibition of activin/nodal signaling leads to formation of extravillous trophoblast, whereas loss of activin/nodal inhibition leads to the formation of syncytiotrophoblasts. Also, the ability of hESCs to form bona fide trophoblasts has been intensely debated. We have examined hESC-derived trophoblasts in the light of stringent criteria that were proposed recently, such as hypomethylation of the ELF5-2b promoter region and down-regulation of HLA class I antigens. We report that trophoblasts that possess these properties can indeed be obtained from hESCs. PMID:25670856

  4. Calcium homeostasis in human placenta: role of calcium-handling proteins.

    PubMed

    Lafond, Julie; Simoneau, Lucie

    2006-01-01

    The human placenta is a transitory organ, representing during pregnancy the unique connection between the mother and her fetus. The syncytiotrophoblast represents the specialized unit in the placenta that is directly involved in fetal nutrition, mainly involving essential nutrients, such as lipids, amino acids, and calcium. This ion is of particular interest since it is actively transported by the placenta throughout pregnancy and is associated with many roles during intrauterine life. At term, the human fetus has accumulated about 25-30 g of calcium. This transfer allows adequate fetal growth and development, since calcium is vital for fetal skeleton mineralization and many cellular functions, such as signal transduction, neurotransmitter release, and cellular growth. Thus, there are many proteins involved in calcium homeostasis in the human placenta. PMID:16861065

  5. Estrogen-related receptor γ (ERRγ) regulates oxygen-dependent expression of voltage-gated potassium (K+) channels and tissue kallikrein during human trophoblast differentiation.

    PubMed

    Luo, Yanmin; Kumar, Premlata; Mendelson, Carole R

    2013-06-01

    Estrogen-related receptor γ (ERRγ) serves a critical O2-dependent regulatory role in the differentiation of human cytotrophoblasts to syncytiotrophoblast. In this study, we investigated expression of genes encoding tissue kallikrein (KLK1) and voltage-gated K(+) channels (KV7) during differentiation of human trophoblasts in culture and the roles of ERRγ and O2 tension in their regulation. Expression of KLK1 and the KV7 channel subunits, KCNQ1, KCNE1, KCNE3, and KCNE5, increased during differentiation of cultured human trophoblast cells in a 20% O2 environment. Notably, together with ERRγ, expression of KLK1, KCNQ1, KCNE1, KCNE3, and KCNE5 was markedly reduced when cells were cultured in a hypoxic environment (2% O2). Moreover, upon transduction of trophoblast cells with short hairpin RNAs for endogenous ERRγ, KLK1, KCNQ1, KCNE1, and KCNE3 expression was significantly decreased. Promoter and site-directed mutagenesis studies in transfected cells identified putative ERRγ response elements within the KLK1 and KCNE1 5'-flanking regions required for ERRγ-stimulated transcriptional activity. Binding of endogenous ERRγ to these ERRγ response elements increased during trophoblast differentiation in culture and was inhibited by hypoxia. The KV7 blocker linopirdine reduced human chorionic gonadotropin secretion and aggregation of cultured human trophoblasts, suggesting a possible role of KV7 channels in cell fusion and differentiation. Illumina gene expression arrays of cultured human trophoblast cells revealed several genes upregulated during syncytiotrophoblast differentiation and downregulated upon ERRγ knockdown involved in cell differentiation, adhesion, and synthesis of steroid and peptide hormones required for placental development and function. Collectively, these findings suggest that ERRγ mediates O2-dependent expression of genes involved in human trophoblast differentiation, function, and vascular homeostasis. PMID:23584901

  6. Estrogen-Related Receptor γ (ERRγ) Regulates Oxygen-Dependent Expression of Voltage-gated Potassium (K+) Channels and Tissue Kallikrein during Human Trophoblast Differentiation

    PubMed Central

    Luo, Yanmin; Kumar, Premlata

    2013-01-01

    Estrogen-related receptor γ (ERRγ) serves a critical O2-dependent regulatory role in the differentiation of human cytotrophoblasts to syncytiotrophoblast. In this study, we investigated expression of genes encoding tissue kallikrein (KLK1) and voltage-gated K+ channels (KV7) during differentiation of human trophoblasts in culture and the roles of ERRγ and O2 tension in their regulation. Expression of KLK1 and the KV7 channel subunits, KCNQ1, KCNE1, KCNE3, and KCNE5, increased during differentiation of cultured human trophoblast cells in a 20% O2 environment. Notably, together with ERRγ, expression of KLK1, KCNQ1, KCNE1, KCNE3, and KCNE5 was markedly reduced when cells were cultured in a hypoxic environment (2% O2). Moreover, upon transduction of trophoblast cells with short hairpin RNAs for endogenous ERRγ, KLK1, KCNQ1, KCNE1, and KCNE3 expression was significantly decreased. Promoter and site-directed mutagenesis studies in transfected cells identified putative ERRγ response elements within the KLK1 and KCNE1 5′-flanking regions required for ERRγ-stimulated transcriptional activity. Binding of endogenous ERRγ to these ERRγ response elements increased during trophoblast differentiation in culture and was inhibited by hypoxia. The KV7 blocker linopirdine reduced human chorionic gonadotropin secretion and aggregation of cultured human trophoblasts, suggesting a possible role of KV7 channels in cell fusion and differentiation. Illumina gene expression arrays of cultured human trophoblast cells revealed several genes upregulated during syncytiotrophoblast differentiation and downregulated upon ERRγ knockdown involved in cell differentiation, adhesion, and synthesis of steroid and peptide hormones required for placental development and function. Collectively, these findings suggest that ERRγ mediates O2-dependent expression of genes involved in human trophoblast differentiation, function, and vascular homeostasis. PMID:23584901

  7. Syncytial knots and intervillous bridges in the human placenta: an ultrastructural study.

    PubMed

    Jones, C J; Fox, H

    1977-11-01

    An electron microscopic study has shown that the syncytial knots of the villi of the human placenta contain aggregated nuclei which exhibit marked degenerative changes; within the cytoplasm there is an abundance of cytoplasmic filaments and many stacks of annulate lamellae. It is suggested that syncytial knots are a sequestration phenomenon in which senescent nuclear material is aggregated and removed from metabolically active areas of the syncytiotrophoblast. Intervillous bridges appear to be formed chiefly by fusion of syncytial knots from adjacent villi, and it seems reasonable that the effete material in a syncytial knot should be used for this purpose. The intervillous bridges hava a fine structure which suggests that they have a mechanical function, and this lends support to the theory that they form an internal strut system within the placenta. PMID:591426

  8. Activation of Protein C in Human Trophoblasts in Culture and Downregulation of Trophoblast Endothelial Protein C Receptor by TNF-α.

    PubMed

    Faioni, E M; Fontana, G; Razzari, C; Avagliano, L; Bulfamante, G; Calvi, E; Doi, P; Marconi, A M

    2015-08-01

    In mice, trophoblasts are equipped with a potent anticoagulant mechanism, the protein C pathway. In human placenta, no functional studies of the protein C pathway are available. Human first-trimester trophoblasts (CK(++) HLA-G(+/-) Vim(-)) were isolated and kept in culture for a maximum of 48 hours. Activation of protein C on trophoblasts was at least as efficient as in endothelial cells (4.43 × 10 (-) (7) nmol/L/min/cell). Endothelial protein C receptor (EPCR) was expressed in syncytiotrophoblasts and extravillous trophoblasts. Downregulation of the messenger RNA of trophoblast EPCR occurred when trophoblasts were challenged with tumor necrosis factor α, and it could be prevented by unfractionated heparin but not by low-molecular-weight heparin at therapeutic doses. In conclusion, there is a functional protein C pathway on human first-trimester trophoblasts which can be modulated by inflammation. This finding has implications for the pathogenesis and prevention of placenta-mediated obstetric complications. PMID:25667200

  9. The presence of kinesin superfamily motor proteins KIFC1 and KIF17 in normal and pathological human placenta.

    PubMed

    Sati, L; Seval-Celik, Y; Unek, G; Korgun, E T; Demir, R

    2009-10-01

    Kinesin superfamily proteins (KIFs) are motor proteins that participate in chromosomal and spindle movements during mitosis and meiosis, and transport membranous organelles and macromolecules fundamental for cellular functions. Although the roles of KIFs in axonal and dendritic transports have been studied extensively, their role in intracellular transport in general is less well known. The diversity of kinesins suggests that each kinesin may have a specific function. Therefore, in this study we aimed to investigate the presence and cellular localization of KIFC1 and KIF17 in normal and pathological human placentas. First-trimester (22-56 days) and normal, preeclamptic (PE), and diabetic-term placental tissues were obtained and further studied by immunohistochemistry (IHC) and Western blot methods. KIFC1 was mainly localized to the syncytiotrophoblast both in early and term placental samples. However, a stronger immunoreactivity was observed both in PE and diabetic placentas compared to normal-term placentas. KIF17 was most intensively localized in developing vascular endothelium in early pregnancy. Even though KIF17 was moderately stained in the endothelium of villi from normal human-term placentas, stronger immunoreactivity was observed in all types of villi of both PE and diabetic placentas. Western blotting of tissue extracts confirmed the IHC results. Here, we demonstrate the presence of KIFC1 and KIF17 in human placenta for the first time. The intense expression of KIFC1 in syncytiotrophoblast and KIF17 in vascular endothelium suggests that both the proteins might be important in a cargo-transport system. An increased expression pattern of both KIFC1 and KIF17 in PE and diabetes might suggest that these proteins may be involved in complex trophoblast functions and placental pathologies. Further studies will clarify the physiological role of KIFs in human placental transport and development. PMID:19679349

  10. Effect of microcystin-LR on human placental villous trophoblast differentiation in vitro.

    PubMed

    Douglas, Gordon C; Thirkill, Twanda L; Kumar, Priyadarsini; Loi, Minerva; Hilborn, Elizabeth D

    2016-04-01

    Microcystin-LR is a cyanobacterial toxin found in surface and recreational waters that inhibits protein phosphatases and may disrupt the cytoskeleton. Microcystins induce apoptosis in hepatocytes at ≤2.0 µM. Nothing is known about the effects of microcystins on human placental trophoblast differentiation and function. The differentiation of villous trophoblasts to form syncytiotrophoblast occurs throughout pregnancy and is essential for normal placental and fetal development. To investigate the effects of microcystin, villous cytotrophoblasts were isolated from term placentas using an established method and exposed to microcystin-LR. Microcystin-LR below the cytotoxic dose of 25 µM did not cause cell rounding or detachment, had no effect on apoptosis, and no effect on the morphological differentiation of mononucleated cytotrophoblasts to multinucleated syncytiotrophoblast. However, secretion of human chorionic gonadotropin (hCG) increased in a microcystin-LR dose-dependent manner. When incubated with l-buthionine sulphoximine (BSO) to deplete glutathione levels, trophoblast morphological differentiation proceeded normally in the presence of microcystin-LR. Microcystin-LR did not disrupt the trophoblast microtubule cytoskeleton, which is known to play a role in trophoblast differentiation. Immunofluorescence studies showed that trophoblasts express organic anion transport protein 1B3 (OATP1B3), a known microcystin transport protein. In comparison to hepatocytes, trophoblasts appear to be more resistant to the toxic effects of microcystin-LR. The physiological implications of increased hCG secretion in response to microcystin-LR exposure remain to be determined. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 427-439, 2016. PMID:25346179

  11. Methylation status and transcriptional expression of the MHC class I loci in human trophoblast cells from term placenta

    SciTech Connect

    Guillaudeux, T.; Rodriguez, A.M.; Girr, M.

    1995-04-01

    Of the various molecular regulatory mechanisms that may be used by human trophoblast cells to down-regulate expression of HLA class I genes, we chose to investigate the methylation of DNA, generally associated with inhibition of transcription. We analyzed the methylation status of different HLA class I loci in villous and extravillous cytotrophoblast cells and in vitro-differentiated syncytiotrophoblast, purified from human term placenta, as well as in the human trophoblast-derived JAR and JEG-3 cell lines. We then compared methylation status and transcriptional activity. An inverse relationship was established between JAR and JEG-3: HLA-A, -B, and -G are methylated and repressed in JAR, whereas in JEG-3, HLA-A is methylated and repressed but HLA-B and -G are partially methylated and transcribed. HLA-E is unmethylated and transcribed in both cell lines. Apart from HLA-E, which is always unmethylated and transcribed, no such relationship exists for the other class I loci in trophoblast cells. Whereas nonclassical HLA-G and classical HLA-A and -B class I genes are undermethylated in both cytotrophoblast and syncytiotrophoblast, they are clearly transcribed in the former but minimally transcribed in the latter subpopulation. Thus, the down-regulation of class I gene expression in the in vitro-differentiated synctiotrophoblast is unlikely to be caused by DNA methylation. Furthermore, there is no detectable expression of any class I molecule at the cell surface of either trophoblast cell subpopulation, suggesting a negative control on translation and/or on the secretory pathway to the plasma membrane. 50 refs., 11 figs., 1 tab.

  12. [Association of encephalic vascular accidents and Chagas disease].

    PubMed

    Lopes, E R; Marquez, J O; da Costa Neto, B; Menezes, A A; Chapadeiro, M E

    1991-01-01

    The frequency of strokes was studied in chronic chagasic and years of age, non-chagasic patients, older than 15 coming to necropsy in Uberaba, from 1979 than 1988. The study consisted of paired sex and age matched controls. Two hundred and eight pairs were analysed. Either ischemic or hemorrhagic strokes were found in 41 (19.7%) of the chagasics and in 55 (26.4%) of the non-chagasic, a difference not significant at the level of 5%. Twelve (75%) of the former had infarcts and 4 (25%) had brain hemorrhage; five (31.3%) of the non-chagasics had ischemic strokes and 11 (68.7%) had hemorrhagic strokes. The differences were significant to the level of 5%. The results indicate a high frequency of ischemic strokes in human Chagas' disease and demonstrate a lesser frequency of hemorrhagic stroke in chagasics when compared with non-chagasics. PMID:1841424

  13. Human Cytomegalovirus Infection Interferes with the Maintenance and Differentiation of Trophoblast Progenitor Cells of the Human Placenta

    PubMed Central

    Tabata, Takako; Petitt, Matthew; Zydek, Martin; Fang-Hoover, June; Larocque, Nicholas; Tsuge, Mitsuru; Gormley, Matthew; Kauvar, Lawrence M.

    2015-01-01

    ABSTRACT Human cytomegalovirus (HCMV) is a major cause of birth defects that include severe neurological deficits, hearing and vision loss, and intrauterine growth restriction. Viral infection of the placenta leads to development of avascular villi, edema, and hypoxia associated with symptomatic congenital infection. Studies of primary cytotrophoblasts (CTBs) revealed that HCMV infection impedes terminal stages of differentiation and invasion by various molecular mechanisms. We recently discovered that HCMV arrests earlier stages involving development of human trophoblast progenitor cells (TBPCs), which give rise to the mature cell types of chorionic villi—syncytiotrophoblasts on the surfaces of floating villi and invasive CTBs that remodel the uterine vasculature. Here, we show that viral proteins are present in TBPCs of the chorion in cases of symptomatic congenital infection. In vitro studies revealed that HCMV replicates in continuously self-renewing TBPC lines derived from the chorion and alters expression and subcellular localization of proteins required for cell cycle progression, pluripotency, and early differentiation. In addition, treatment with a human monoclonal antibody to HCMV glycoprotein B rescues differentiation capacity, and thus, TBPCs have potential utility for evaluation of the efficacies of novel antiviral antibodies in protecting and restoring placental development. Our results suggest that HCMV replicates in TBPCs in the chorion in vivo, interfering with the earliest steps in the growth of new villi, contributing to virus transmission and impairing compensatory development. In cases of congenital infection, reduced responsiveness of the placenta to hypoxia limits the transport of substances from maternal blood and contributes to fetal growth restriction. IMPORTANCE Human cytomegalovirus (HCMV) is a leading cause of birth defects in the United States. Congenital infection can result in permanent neurological defects, mental retardation

  14. Progesterone and human placental lactogen inhibit leptin secretion on cultured trophoblast cells from human placentas at term.

    PubMed

    Coya, Raquel; Martul, Pedro; Algorta, Jaime; Aniel-Quiroga, Ma Angeles; Busturia, Ma Angeles; Señarís, Rosa

    2005-07-01

    The placenta is an important source of leptin production that contributes to the state of hyperleptinemia observed in pregnant women. Moreover, the synthesis of leptin and its receptors by syncytiotrophoblast cells suggests a potential paracrine or autocrine action of leptin in the placenta. In the present study we examined the effect of gestational hormones, human chorionic gonadotropin (hCG), human placental lactogen (hPL), progesterone and estradiol, on in vitro leptin release by human term trophoblast cells in culture. Placentas at term were obtained immediately after delivery from mothers with uncomplicated pregnancies. Leptin levels were measured by enzyme-linked immunosorbent assay in culture media of trophoblasts maintained in monolayer culture for 24, 48 and 72 h with different hormonal treatments or placebo. Treatment with hPL and progesterone led to a time- and dose-dependent decrease in leptin release that was statistically significant after 24 h, with a maximal effect after 72 h of incubation. In contrast, incubation with estradiol and hCG did not have exhibit any effect on leptin secretion at any of the doses and times assayed in this work. The results obtained in this study support that leptin can be considered a gestational hormone implied in the endocrine function of the placenta and that its secretion is at least partially regulated by steroid and peptidic reproductive hormones in trophoblast cells in vitro. PMID:16048798

  15. The CD200 tolerance-signaling molecule and its receptor, CD200R1, are expressed in human placental villus trophoblast and in peri-implant decidua by 5 weeks' gestation.

    PubMed

    Clark, David A; Arredondo, Jorge L; Dhesy-Thind, Sukhbinder

    2015-11-01

    CD200 expression in murine trophoblast and decidua prevents semi-allogeneic and LPS-induced abortions by binding to CD200 receptor-bearing cells to suppress NK activity, induces IDO in macrophages, and promotes the generation of regulatory T cell subsets. CD200 and its receptor CD200R1 reported in 7-9 weeks' gestation human villus trophoblasts are reduced in spontaneous abortion syncytiotrophoblasts. By specific antibody staining, we find that both CD200 and CD200R1 are expressed even earlier, by 5 weeks' gestation, by villus trophoblasts and by decidual cells. Expression of CD200 was validated using two independent antibodies. CD200-CD200R1 signaling may be required for human pregnancy success. PMID:26123445

  16. Trophoblast lineage cells derived from human induced pluripotent stem cells

    SciTech Connect

    Chen, Ying; Wang, Kai; Chandramouli, Gadisetti V.R.; Knott, Jason G.; Leach, Richard

    2013-07-12

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro.

  17. HCMV Infection of Human Trophoblast Progenitor Cells of the Placenta Is Neutralized by a Human Monoclonal Antibody to Glycoprotein B and Not by Antibodies to the Pentamer Complex

    PubMed Central

    Zydek, Martin; Petitt, Matthew; Fang-Hoover, June; Adler, Barbara; Kauvar, Lawrence M.; Pereira, Lenore; Tabata, Takako

    2014-01-01

    Human cytomegalovirus (HCMV) is the major viral cause of congenital infection and birth defects. Primary maternal infection often results in virus transmission, and symptomatic babies can have permanent neurological deficiencies and deafness. Congenital infection can also lead to intrauterine growth restriction, a defect in placental transport. HCMV replicates in primary cytotrophoblasts (CTBs), the specialized cells of the placenta, and inhibits differentiation/invasion. Human trophoblast progenitor cells (TBPCs) give rise to the mature cell types of the chorionic villi, CTBs and multi-nucleated syncytiotrophoblasts (STBs). Here we report that TBPCs are fully permissive for pathogenic and attenuated HCMV strains. Studies with a mutant virus lacking a functional pentamer complex (gH/gL/pUL128-131A) showed that virion entry into TBPCs is independent of the pentamer. In addition, infection is blocked by a potent human neutralizing monoclonal antibody (mAb), TRL345, reactive with glycoprotein B (gB), but not mAbs to the pentamer proteins pUL130/pUL131A. Functional studies revealed that neutralization of infection preserved the capacity of TBPCs to differentiate and assemble into trophospheres composed of CTBs and STBs in vitro. Our results indicate that mAbs to gB protect trophoblast progenitors of the placenta and could be included in antibody treatments developed to suppress congenital infection and prevent disease. PMID:24651029

  18. A microphysiological model of the human placental barrier.

    PubMed

    Blundell, Cassidy; Tess, Emily R; Schanzer, Ariana S R; Coutifaris, Christos; Su, Emily J; Parry, Samuel; Huh, Dongeun

    2016-08-01

    During human pregnancy, the fetal circulation is separated from maternal blood in the placenta by two cell layers - the fetal capillary endothelium and placental trophoblast. This placental barrier plays an essential role in fetal development and health by tightly regulating the exchange of endogenous and exogenous materials between the mother and the fetus. Here we present a microengineered device that provides a novel platform to mimic the structural and functional complexity of this specialized tissue in vitro. Our model is created in a multilayered microfluidic system that enables co-culture of human trophoblast cells and human fetal endothelial cells in a physiologically relevant spatial arrangement to replicate the characteristic architecture of the human placental barrier. We have engineered this co-culture model to induce progressive fusion of trophoblast cells and to form a syncytialized epithelium that resembles the syncytiotrophoblast in vivo. Our system also allows the cultured trophoblasts to form dense microvilli under dynamic flow conditions and to reconstitute expression and physiological localization of membrane transport proteins, such as glucose transporters (GLUTs), critical to the barrier function of the placenta. To provide a proof-of-principle for using this microdevice to recapitulate native function of the placental barrier, we demonstrated physiological transport of glucose across the microengineered maternal-fetal interface. Importantly, the rate of maternal-to-fetal glucose transfer in this system closely approximated that measured in ex vivo perfused human placentas. Our "placenta-on-a-chip" platform represents an important advance in the development of new technologies to model and study the physiological complexity of the human placenta for a wide variety of applications. PMID:27229450

  19. Ultrastructural study on human placenta from intrauterine growth retardation cases.

    PubMed

    Battistelli, Michela; Burattini, Sabrina; Pomini, Francesco; Scavo, Maria; Caruso, Alessandro; Falcieri, Elisabetta

    2004-10-01

    A morphological study was performed on 27 human placentas from normal gestations (Group 1) and compared with those from eight cases of intrauterine growth restriction (IUGR) (Group 2). Semithin section light microscopy, transmission, and scanning electron microscopy were carried out on trophoblastic terminal villi, carefully identified under the stereomicroscope. In growth retardation cases, villi appear longer, thinner, and less vascularized, compared to the normal condition. Fibrinoid, an extracellular material of hematic origin, frequently fills villar stroma. The density of apical microvilli appears considerably reduced and occasional microvilli-free areas are observed in growth retardation cases. Moreover, the underlying basal membrane appears significantly thicker than that of normal syncytiotrophoblast. Recently, particular attention has been paid to apoptosis as a possible cell deletion mechanism in growth restriction. In our study, a majority of typical apoptotic features appear indifferently in both IUGR and normal pregnancy. Our data hints that growth retardation might be correlated with a complex of structural changes, suggestive of maternofetal traffic downregulation, but further studies are required to understand the underlying functional mechanisms. PMID:15605416

  20. Human extravillous trophoblast invasion: intrinsic and extrinsic regulation.

    PubMed

    Menkhorst, E; Winship, A; Van Sinderen, M; Dimitriadis, E

    2016-03-01

    During the establishment of pregnancy, a human blastocyst implants into the uterine endometrium to facilitate the formation of a functional placenta. Implantation involves the blastocyst adhering to the uterine luminal epithelium before the primitive syncytiotrophoblast and subsequently specialised cells, the extravillous trophoblast (EVT), invade into the decidua in order to engraft and remodel uterine spiral arteries, creating the placental blood supply at the end of the first trimester. Defects in EVT invasion lead to abnormal placentation and thus adverse pregnancy outcomes. The local decidual environment is thought to play a key role in regulating trophoblast invasion. Here we describe the major cell types present in the decidua during the first trimester of pregnancy and review what is known about their regulation of EVT invasion. Overall, the evidence suggests that in a healthy pregnancy almost all cell types in the decidua actively promote EVT invasion and, further, that reduced EVT invasion towards the end of the first trimester is regulated, in part, by the reduced invasive capacity of EVTs shown at this time. PMID:25163485

  1. Angiogenin distribution in human term placenta, and expression by cultured trophoblastic cells

    PubMed Central

    Pavlov, Nadine; Hatzi, Elissavet; Bassaglia, Yann; Frendo, Jean-Louis; Evain-Brion, Danièle; Badet, Josette

    2003-01-01

    Human angiogenin is a 14-kDa secreted protein with angiogenic and ribonucleolytic activities. Angiogenin is associated with tumour development but is also present in normal biological fluids and tissues. To further address the physiological role of angiogenin, we studied its expression in situ and in vitro, using the human term placenta as a model of physiological angiogenesis. Angiogenin was immunodetected by light and transmission electron microscopy, and its cellular distribution was established by double immunolabelling with cell markers including von Willebrand factor, platelet/endothelial cell adhesion molecule-1 (PECAM-1), CD34, Tie-2, vascular endothelial cadherin (VE-cadherin), vascular endothelial growth factor receptor-2 (VEGF-R2), erythropoeitin receptor (Epo-R), alpha-smooth muscle actin, CD45, cytokeratin 7, and Ki-67. Angiogenin immunoreactivity was detected in villous and extravillous trophoblasts, the trophoblast basement membrane, the endothelial basal lamina, foetal blood vessels, foetal and maternal red blood cells, and amnionic cells. Its expression was confirmed by in situ hybridisation with a digoxygenin-labelled cDNA probe and reverse transcriptase-polymerase chain reaction amplification. Villous cytotrophoblasts, isolated and differentiated in vitro into a functional syncytiotrophoblast, expressed and secreted angiogenin. Given its known biological activities in vitro and its observed pattern of expression, these data suggest that, in human placenta, angiogenin has a role not only in angiogenesis but also in vascular and tissue homeostasis, maternal immune tolerance of the foetus, and host defences. PMID:15166501

  2. Human Hemochromatosis Protein (HFE) Immunoperoxidase Stain Highlights Choriocarcinoma within Mixed Germ Cell Tumors.

    PubMed

    Cox, Jesse L; Talmon, Geoffrey A; Koepsell, Scott A

    2016-01-01

    Identification of choriocarcinoma within a germ cell tumor can have major implications for the subsequent staging and treatment of testicular neoplasms. Immunoperoxidase staining greatly enhances the speed and sensitivity of identifying occult, though clinically significant, tumor components. In mixed germ cell tumors, staining for beta-human chorionic gonadotropin (β-hCG) has been historically used to assess for the presence and burden of choriocarcinoma. However, current β-hCG stains produce variable, intense staining of trophoblastic elements and surrounding tissues, clouding the assessment of true-positive staining. Human hemochromatosis protein (HFE) is a membrane bound mediator of iron transport expressed at high levels within placenta. Additionally, previous reports have demonstrated that choriocarcinoma cell lines express HFE, although in vivo expression had not been examined. To address whether HFE can stain trophoblastic elements, HFE immunohistochemistry was conducted in choriocarcinoma (n = 4), mixed germ cell tumors (n = 11), seminoma (n = 4), and placenta (n = 11). HFE consistently demonstrated cytoplasmic and membranous staining, highlighting both syncytiotrophoblasts and cytotrophoblasts within choriocarcinoma and placenta. Staining of intratumoral white blood cells was observed within seminomas and mixed germ cell tumors, corroborating prior reports stating that HFE highlights monocytes and macrophages. Taken together, HFE may serve as an alternative target from β-hCG for immunoperoxidase studies when highlighting choriocarcinoma. PMID:27034532

  3. Human Hemochromatosis Protein (HFE) Immunoperoxidase Stain Highlights Choriocarcinoma within Mixed Germ Cell Tumors

    PubMed Central

    Talmon, Geoffrey A.; Koepsell, Scott A.

    2016-01-01

    Identification of choriocarcinoma within a germ cell tumor can have major implications for the subsequent staging and treatment of testicular neoplasms. Immunoperoxidase staining greatly enhances the speed and sensitivity of identifying occult, though clinically significant, tumor components. In mixed germ cell tumors, staining for beta-human chorionic gonadotropin (β-hCG) has been historically used to assess for the presence and burden of choriocarcinoma. However, current β-hCG stains produce variable, intense staining of trophoblastic elements and surrounding tissues, clouding the assessment of true-positive staining. Human hemochromatosis protein (HFE) is a membrane bound mediator of iron transport expressed at high levels within placenta. Additionally, previous reports have demonstrated that choriocarcinoma cell lines express HFE, although in vivo expression had not been examined. To address whether HFE can stain trophoblastic elements, HFE immunohistochemistry was conducted in choriocarcinoma (n = 4), mixed germ cell tumors (n = 11), seminoma (n = 4), and placenta (n = 11). HFE consistently demonstrated cytoplasmic and membranous staining, highlighting both syncytiotrophoblasts and cytotrophoblasts within choriocarcinoma and placenta. Staining of intratumoral white blood cells was observed within seminomas and mixed germ cell tumors, corroborating prior reports stating that HFE highlights monocytes and macrophages. Taken together, HFE may serve as an alternative target from β-hCG for immunoperoxidase studies when highlighting choriocarcinoma. PMID:27034532

  4. Long-Term Endurance Exercise in Humans Stimulates Cell Fusion of Myoblasts along with Fusogenic Endogenous Retroviral Genes In Vivo

    PubMed Central

    Suhr, Frank; Konou, Thierry M.; Tappe, Kim A.; Toigo, Marco; Jung, Hans H.; Henke, Christine; Steigleder, Ruth; Strissel, Pamela L.; Huebner, Hanna; Beckmann, Matthias W.; van der Keylen, Piet; Schoser, Benedikt; Schiffer, Thorsten; Frese, Laura; Bloch, Wilhelm; Strick, Reiner

    2015-01-01

    Myogenesis is defined as growth, differentiation and repair of muscles where cell fusion of myoblasts to multinucleated myofibers is one major characteristic. Other cell fusion events in humans are found with bone resorbing osteoclasts and placental syncytiotrophoblasts. No unifying gene regulation for natural cell fusions has been found. We analyzed skeletal muscle biopsies of competitive cyclists for muscle-specific attributes and expression of human endogenous retrovirus (ERV) envelope genes due to their involvement in cell fusion of osteoclasts and syncytiotrophoblasts. Comparing muscle biopsies from post- with the pre-competitive seasons a significant 2.25-fold increase of myonuclei/mm fiber, a 2.38-fold decrease of fiber area/nucleus and a 3.1-fold decrease of satellite cells (SCs) occurred. We propose that during the pre-competitive season SC proliferation occurred following with increased cell fusion during the competitive season. Expression of twenty-two envelope genes of muscle biopsies demonstrated a significant increase of putative muscle-cell fusogenic genes Syncytin-1 and Syncytin-3, but also for the non-fusogenic erv3. Immunohistochemistry analyses showed that Syncytin-1 mainly localized to the sarcolemma of myofibers positive for myosin heavy-chain isotypes. Cellular receptors SLC1A4 and SLC1A5 of Syncytin-1 showed significant decrease of expression in post-competitive muscles compared with the pre-competitive season, but only SLC1A4 protein expression localized throughout the myofiber. Erv3 protein was strongly expressed throughout the myofiber, whereas envK1-7 localized to SC nuclei and myonuclei. Syncytin-1 transcription factors, PPARγ and RXRα, showed no protein expression in the myofiber, whereas the pCREB-Ser133 activator of Syncytin-1 was enriched to SC nuclei and myonuclei. Syncytin-1, Syncytin-3, SLC1A4 and PAX7 gene regulations along with MyoD1 and myogenin were verified during proliferating or actively-fusing human primary myoblast cell

  5. MSX2 Induces Trophoblast Invasion in Human Placenta

    PubMed Central

    Lu, Junjie; Yang, Genling; Tian, Na; Wang, Xiaojie; Tan, Yi; Tan, Dongmei

    2016-01-01

    Normal implantation depends on appropriate trophoblast growth and invasion. Inadequate trophoblast invasion results in pregnancy-related disorders, such as early miscarriage and pre-eclampsia, which are dangerous to both the mother and fetus. Msh Homeobox 2 (MSX2), a member of the MSX family of homeobox proteins, plays a significant role in the proliferation and differentiation of various cells and tissues, including ectodermal organs, teeth, and chondrocytes. Recently, MSX2 was found to play important roles in the invasion of cancer cells into adjacent tissues via the epithelial-mesenchymal transition (EMT). However, the role of MSX2 in trophoblastic invasion during placental development has yet to be explored. In the present study, we detected MSX2 expression in cytotrophoblast, syncytiotrophoblast, and extravillous cytotrophoblast cells of first or third trimester human placentas via immunohistochemistry analysis. Furthermore, we found that the in vitro invasive ability of HTR8/SVneo cells was enhanced by exogenous overexpression of MSX2, and that this effect was accompanied by increased protein expression of matrix metalloproteinase-2 (MMP-2), vimentin, and β-catenin. Conversely, treatment of HTR8/SVneo cells with MSX2-specific siRNAs resulted in decreased protein expression of MMP-2, vimentin, and β-catenin, and reduced invasion levels in a Matrigel invasion test. Notably, however, treatment with the MSX2 overexpression plasmid and the MSX2 siRNAs had no effect on the mRNA expression levels of β-catenin. Meanwhile, overexpression of MSX2 and treatment with the MSX2-specific siRNA resulted in decreased and increased E-cadherin expression, respectively, in JEG-3 cells. Lastly, the protein expression levels of MSX2 were significantly lower in human pre-eclamptic placental villi than in the matched control placentas. Collectively, our results suggest that MSX2 may induce human trophoblast cell invasion, and dysregulation of MSX2 expression may be associated

  6. MSX2 Induces Trophoblast Invasion in Human Placenta.

    PubMed

    Liang, Hao; Zhang, Qian; Lu, Junjie; Yang, Genling; Tian, Na; Wang, Xiaojie; Tan, Yi; Tan, Dongmei

    2016-01-01

    Normal implantation depends on appropriate trophoblast growth and invasion. Inadequate trophoblast invasion results in pregnancy-related disorders, such as early miscarriage and pre-eclampsia, which are dangerous to both the mother and fetus. Msh Homeobox 2 (MSX2), a member of the MSX family of homeobox proteins, plays a significant role in the proliferation and differentiation of various cells and tissues, including ectodermal organs, teeth, and chondrocytes. Recently, MSX2 was found to play important roles in the invasion of cancer cells into adjacent tissues via the epithelial-mesenchymal transition (EMT). However, the role of MSX2 in trophoblastic invasion during placental development has yet to be explored. In the present study, we detected MSX2 expression in cytotrophoblast, syncytiotrophoblast, and extravillous cytotrophoblast cells of first or third trimester human placentas via immunohistochemistry analysis. Furthermore, we found that the in vitro invasive ability of HTR8/SVneo cells was enhanced by exogenous overexpression of MSX2, and that this effect was accompanied by increased protein expression of matrix metalloproteinase-2 (MMP-2), vimentin, and β-catenin. Conversely, treatment of HTR8/SVneo cells with MSX2-specific siRNAs resulted in decreased protein expression of MMP-2, vimentin, and β-catenin, and reduced invasion levels in a Matrigel invasion test. Notably, however, treatment with the MSX2 overexpression plasmid and the MSX2 siRNAs had no effect on the mRNA expression levels of β-catenin. Meanwhile, overexpression of MSX2 and treatment with the MSX2-specific siRNA resulted in decreased and increased E-cadherin expression, respectively, in JEG-3 cells. Lastly, the protein expression levels of MSX2 were significantly lower in human pre-eclamptic placental villi than in the matched control placentas. Collectively, our results suggest that MSX2 may induce human trophoblast cell invasion, and dysregulation of MSX2 expression may be associated

  7. Alpha-1-Antitrypsin: A Novel Human High Temperature Requirement Protease A1 (HTRA1) Substrate in Human Placental Tissue

    PubMed Central

    Frochaux, Violette; Hildebrand, Diana; Talke, Anja; Linscheid, Michael W.; Schlüter, Hartmut

    2014-01-01

    The human serine protease high temperature requirement A1 (HTRA1) is highly expressed in the placental tissue, especially in the last trimester of gestation. This suggests that HTRA1 is involved in placental formation and function. With the aim of a better understanding of the role of HTRA1 in the placenta, candidate substrates were screened in a placenta protein extract using a gel-based mass spectrometric approach. Protease inhibitor alpha-1-antitrypsin, actin cytoplasmic 1, tropomyosin beta chain and ten further proteins were identified as candidate substrates of HTRA1. Among the identified candidate substrates, alpha-1-antitrypsin (A1AT) was considered to be of particular interest because of its important role as protease inhibitor. For investigation of alpha-1-antitrypsin as substrate of HTRA1 synthetic peptides covering parts of the sequence of alpha-1-antitrypsin were incubated with HTRA1. By mass spectrometry a specific cleavage site was identified after met-382 (AIPM382↓383SIPP) within the reactive centre loop of alpha-1-antitrypsin, resulting in a C-terminal peptide comprising 36 amino acids. Proteolytic removal of this peptide from alpha-1-antitrypsin results in a loss of its inhibitor function. Beside placental alpha-1-antitrypsin the circulating form in human plasma was also significantly degraded by HTRA1. Taken together, our data suggest a link between the candidate substrates alpha-1-antitrypsin and the function of HTRA1 in the placenta in the syncytiotrophoblast, the cell layer attending to maternal blood in the villous tree of the human placenta. Data deposition: Mass spectrometry (MS) data have been deposited to the ProteomeXchange with identifier PXD000473. PMID:25329061

  8. TGF-β1 up-regulates connexin43 expression: a potential mechanism for human trophoblast cell differentiation.

    PubMed

    Cheng, Jung-Chien; Chang, Hsun-Ming; Fang, Lanlan; Sun, Ying-Pu; Leung, Peter C K

    2015-07-01

    Connexin43 (Cx43)-mediated gap junctional intercellular communication (GJIC) are required for human trophoblast differentiation. To date, whether Cx43 mediates TGF-β1-induced trophoblast differentiation has not been determined. We showed that treatment with TGF-β1 increased Cx43 expression and GJIC in HTR-8/SVneo human trophoblast cells. In addition, Smad and ERK1/2 signaling pathways were involved in TGF-β1-induced up-regulation of Cx43. Moreover, TGF-β1 increased the expression of the syncytiotrophoblast marker, β-hCG. Importantly, knockdown of Cx43 abolished the TGF-β1-induced up-regulation of β-hCG. Furthermore, overexpression of Cx43 up-regulated β-hCG expression. These results provide evidence that Cx43 and GJIC activity are up-regulated by TGF-β1 in human trophoblast cells, which subsequently contributes to TGF-β1-induced trophoblast differentiation. PMID:25560303

  9. Heightened potency of human pluripotent stem cell lines created by transient BMP4 exposure

    PubMed Central

    Yang, Ying; Adachi, Katsuyuki; Sheridan, Megan A.; Alexenko, Andrei P.; Schust, Danny J.; Schulz, Laura C.; Ezashi, Toshihiko; Roberts, R. Michael

    2015-01-01

    Human pluripotent stem cells (PSCs) show epiblast-type pluripotency that is maintained with ACTIVIN/FGF2 signaling. Here, we report the acquisition of a unique stem cell phenotype by both human ES cells (hESCs) and induced pluripotent stem cells (iPSCs) in response to transient (24–36 h) exposure to bone morphogenetic protein 4 (BMP4) plus inhibitors of ACTIVIN signaling (A83-01) and FGF2 (PD173074), followed by trypsin dissociation and recovery of colonies capable of growing on a gelatin substratum in standard medium for human PSCs at low but not high FGF2 concentrations. The self-renewing cell lines stain weakly for CDX2 and strongly for NANOG, can be propagated clonally on either Matrigel or gelatin, and are morphologically distinct from human PSC progenitors on either substratum but still meet standard in vitro criteria for pluripotency. They form well-differentiated teratomas in immune-compromised mice that secrete human chorionic gonadotropin (hCG) into the host mouse and include small areas of trophoblast-like cells. The cells have a distinct transcriptome profile from the human PSCs from which they were derived (including higher expression of NANOG, LEFTY1, and LEFTY2). In nonconditioned medium lacking FGF2, the colonies spontaneously differentiated along multiple lineages, including trophoblast. They responded to PD173074 in the absence of both FGF2 and BMP4 by conversion to trophoblast, and especially syncytiotrophoblast, whereas an A83-01/PD173074 combination favored increased expression of HLA-G, a marker of extravillous trophoblast. Together, these data suggest that the cell lines exhibit totipotent potential and that BMP4 can prime human PSCs to a self-renewing alternative state permissive for trophoblast development. The results may have implications for regulation of lineage decisions in the early embryo. PMID:25870291

  10. Human pluripotent stem cells as a model of trophoblast differentiation in both normal development and disease.

    PubMed

    Horii, Mariko; Li, Yingchun; Wakeland, Anna K; Pizzo, Donald P; Nelson, Katharine K; Sabatini, Karen; Laurent, Louise Chang; Liu, Ying; Parast, Mana M

    2016-07-01

    Trophoblast is the primary epithelial cell type in the placenta, a transient organ required for proper fetal growth and development. Different trophoblast subtypes are responsible for gas/nutrient exchange (syncytiotrophoblasts, STBs) and invasion and maternal vascular remodeling (extravillous trophoblasts, EVTs). Studies of early human placental development are severely hampered by the lack of a representative trophoblast stem cell (TSC) model with the capacity for self-renewal and the ability to differentiate into both STBs and EVTs. Primary cytotrophoblasts (CTBs) isolated from early-gestation (6-8 wk) human placentas are bipotential, a phenotype that is lost with increasing gestational age. We have identified a CDX2(+)/p63(+) CTB subpopulation in the early postimplantation human placenta that is significantly reduced later in gestation. We describe a reproducible protocol, using defined medium containing bone morphogenetic protein 4 by which human pluripotent stem cells (hPSCs) can be differentiated into CDX2(+)/p63(+) CTB stem-like cells. These cells can be replated and further differentiated into STB- and EVT-like cells, based on marker expression, hormone secretion, and invasive ability. As in primary CTBs, differentiation of hPSC-derived CTBs in low oxygen leads to reduced human chorionic gonadotropin secretion and STB-associated gene expression, instead promoting differentiation into HLA-G(+) EVTs in an hypoxia-inducible, factor-dependent manner. To validate further the utility of hPSC-derived CTBs, we demonstrated that differentiation of trisomy 21 (T21) hPSCs recapitulates the delayed CTB maturation and blunted STB differentiation seen in T21 placentae. Collectively, our data suggest that hPSCs are a valuable model of human placental development, enabling us to recapitulate processes that result in both normal and diseased pregnancies. PMID:27325764

  11. CpG methylation suppresses transcriptional activity of human syncytin-1 in non-placental tissues

    SciTech Connect

    Matouskova, Magda; Blazkova, Jana; Pajer, Petr; Pavlicek, Adam; Hejnar, Jiri . E-mail: hejnar@img.cas.cz

    2006-04-15

    Syncytin-1 is a captive envelope glycoprotein encoded by one of human endogenous retroviruses W. It is expressed exclusively in the placental trophoblast where it participates in cell-to-cell fusion during differentiation of syncytiotrophobast. In other tissues, however, syncytin-1 expression must be kept in check because inadvertent cell fusion might be dangerous for tissue organization and integrity. We describe here an inverse correlation between CpG methylation of syncytin-1 5' long terminal repeat and its expression. Hypomethylation of the syncytin-1 5' long terminal repeat in the placenta and in the choriocarcinoma-derived cell line BeWo was detected. However, other analyzed primary cells and cell lines non-expressing syncytin-1 contain proviruses heavily methylated in this sequence. CpG methylation of syncytin-1 is resistant to the effect of the demethylating agent 5-azacytidine. The inhibitory role of CpG methylation is further confirmed by transient transfection of in-vitro-methylated syncytin-1 promoter-driven reporter construct. Altogether, we conclude that CpG methylation plays a principal role in the transcriptional suppression of syncytin-1 in non-placental tissues, and, in contrast, demethylation of the syncytin-1 promoter in trophoblast is a prerequisite for its expression and differentiation of multinucleated syncytiotrophoblast.

  12. The role of CX3CL1 in fetal-maternal interaction during human gestation.

    PubMed

    Kervancioglu Demirci, Elif; Salamonsen, Lois A; Gauster, Martin

    2016-03-01

    Embryo implantation and subsequent placentation require a fine balanced fetal-maternal cross-talk of hormones, cytokines and chemokines. Amongst the group of chemokines, CX3CL1 (also known as fractalkine) has recently attracted attention in the field of reproductive research. It exists both as membrane-bound and soluble isoforms. On the basis of current experimental evidence, fractalkine is suggested to regulate adhesion and migration processes in fetal-maternal interaction at different stages of human pregnancy. Expressed by uterine glandular epithelial cells, predominantly during the mid-secretory phase of the menstrual cycle, fractalkine appears to prime the blastocyst for forthcoming implantation. After implantation, fractalkine is suggested to regulate invasion of extravillous trophoblasts by altering their expression profile of adhesion molecules. With onset of perfusion of the intervillous space at the end of first trimester, fractalkine present at the apical microvillous plasma membrane of the syncytiotrophoblast may mediate close interaction of placental villi with circulating maternal blood cells. PMID:26745855

  13. Transferability of Trypanosoma cruzi from mixed human host infection to Triatoma infestans and from insects to axenic culture.

    PubMed

    Ortiz, Sylvia; Zulantay, Inés; Apt, Werner; Saavedra, Miguel; Solari, Aldo

    2015-02-01

    The etiologic agent of Chagas disease is Trypanosoma cruzi, a protozoan whose life cycle involves obligatory passage through vertebrate and invertebrate hosts in a series of stages. The aim of this study was to explore the transferability of mixed discrete typing units (DTUs) of T. cruzi present in chronic chagasic patients when passed through an invertebrate host during xenodiagnosis (XD) and then when transferred to axenic cultures to obtain T. cruzi isolates. DTUs of T. cruzi present in these two hosts and axenic cultures were identified by kDNA PCR amplification and subsequent hybridization with DTU-specific probes. Mixtures of Tc I, Tc II, Tc V and Tc VI DTUs were detected in blood samples. However as a result of XD and axenic cultures it was possible to identify mostly Tc V. We conclude that the transferability of an isolate of T.cruzi derived from mixed DTUs present in human blood depends upon the starved invertebrate host used for xenodiagnosis. PMID:25240699

  14. Effects of cadmium of the human placenta in vitro

    SciTech Connect

    Wier, P.J.

    1985-01-01

    Human placental lobules (25 g) were maintained in vitro for 12 hours by dual perfusion of the fetal vessels and intervillous space (maternal circulation). A synthetic tissue culture medium was used for the perfusates. Maternal perfusate was gassed with 95% O/sub 2//5% CO/sub 2/; fetal perfusate was gassed with 95% N/sub 2//5% CO/sub 2/. Both perfusates were recirculated (maternal 15-25 ml/min, fetal 3 ml/min) and exchanged for fresh perfusates every 4 hours. The integrity of the fetal vasculature was demonstrated by the stabilities of fetal arterial pressure (30-36 mm Hg) and circulatory volume (volume loss <2 ml/h). The metabolic viability of the placenta was documented by measurements of oxygen consumption (100-137 umole/min.kg), glucose consumption (133-163 umole/min.kg), and lactate production (163-229 umole/min.kg). Exposure of placenta to 10 nmole Cd/ml maternal perfusate led to accumulation of cadmium (45 nmole Cd/g), yet there was limited movement of cadmium from maternal to fetal circulations. This exposure did not result in significant changes in fetal capillary permeability of resistance, oxygen or glucose consumptions, lactate production, nCg release, transport of AlB by placental slices, or ultrastructure. Transfer of zinc from maternal to fetal circulations did not appear to be reduced. Exposure of perfused placenta to 100 nmole Cd/ml maternal perfusate resulted in a cadmium burden of 150 nmole Cd/g. This exposure induced syncytiotrophoblast necrosis, increased fetal capillary permeability, and reduced hCG release.

  15. Effect of bromodichloromethane on chorionic gonadotrophin secretion by human placental trophoblast cultures.

    PubMed

    Chen, Jiangang; Douglas, Gordon C; Thirkill, Twanda L; Lohstroh, Peter N; Bielmeier, Susan R; Narotsky, Michael G; Best, Deborah S; Harrison, Randy A; Natarajan, Kala; Pegram, Rex A; Overstreet, James W; Lasley, Bill L

    2003-11-01

    Bromodichloromethane (BDCM) is a trihalomethane found in drinking water as a by-product of disinfection processes. BDCM is hepatotoxic and nephrotoxic in rodents and has been reported to cause strain-specific full-litter resorption in F344 rats during the luteinizing hormone-dependent phase of pregnancy. In humans, epidemiological studies suggest an association between exposure to BDCM in drinking water and increased risk of spontaneous abortion. To begin to address the mechanism(s) of BDCM-induced spontaneous abortion, we hypothesized that BDCM targets the placenta. Primary cultures of human term trophoblast cells were used as an in vitro model to test this hypothesis. Trophoblasts were allowed to differentiate into multinucleated syncytiotrophoblast-like colonies, after which they were incubated for 24 h with different concentrations of BDCM (20 nM to 2 mM). Culture media were collected and assayed for immunoreactive and bioactive chorionic gonadotropin (CG). Cultures exposed to BDCM showed a dose-dependent decrease in the secretion of immunoreactive CG as well as bioactive CG. The lowest effective BDCM concentration was 20 nM, approximately 35-times higher than the maximum concentration reported in human blood (0.57 nM). Trophoblast morphology and viability were similar in controls and cultures exposed to BDCM. We conclude that BDCM perturbs CG secretion by differentiated trophoblasts in vitro. This suggests that the placenta is a likely target of BDCM toxicity in the human and that this could be related to the adverse pregnancy outcomes associated with BDCM. PMID:12970577

  16. Expression and Functional Activity of the Human Bitter Taste Receptor TAS2R38 in Human Placental Tissues and JEG-3 Cells.

    PubMed

    Wölfle, Ute; Elsholz, Floriana A; Kersten, Astrid; Haarhaus, Birgit; Schumacher, Udo; Schempp, Christoph M

    2016-01-01

    Bitter taste receptors (TAS2Rs) are expressed in mucous epithelial cells of the tongue but also outside the gustatory system in epithelial cells of the colon, stomach and bladder, in the upper respiratory tract, in the cornified squamous epithelium of the skin as well as in airway smooth muscle cells, in the testis and in the brain. In the present work we addressed the question if bitter taste receptors might also be expressed in other epithelial tissues as well. By staining a tissue microarray with 45 tissue spots from healthy human donors with an antibody directed against the best characterized bitter taste receptor TAS2R38, we observed an unexpected strong TAS2R38 expression in the amniotic epithelium, syncytiotrophoblast and decidua cells of the human placenta. To analyze the functionality we first determined the TAS2R38 expression in the placental cell line JEG-3. Stimulation of these cells with diphenidol, a clinically used antiemetic agent that binds TAS2Rs including TAS2R38, demonstrated the functionality of the TAS2Rs by inducing calcium influx. Restriction enzyme based detection of the TAS2R38 gene allele identified JEG-3 cells as PTC (phenylthiocarbamide)-taster cell line. Calcium influx induced by PTC in JEG-3 cells could be inhibited with the recently described TAS2R38 inhibitor probenecid and proved the specificity of the TAS2R38 activation. The expression of TAS2R38 in human placental tissues points to further new functions and hitherto unknown endogenous ligands of TAS2Rs far beyond bitter tasting. PMID:26950109

  17. Real-Time Tracking of BODIPY-C12 Long-Chain Fatty Acid in Human Term Placenta Reveals Unique Lipid Dynamics in Cytotrophoblast Cells.

    PubMed

    Kolahi, Kevin; Louey, Samantha; Varlamov, Oleg; Thornburg, Kent

    2016-01-01

    While the human placenta must provide selected long-chain fatty acids to support the developing fetal brain, little is known about the mechanisms underlying the transport process. We tracked the movement of the fluorescently labeled long-chain fatty acid analogue, BODIPY-C12, across the cell layers of living explants of human term placenta. Although all layers took up the fatty acid, rapid esterification of long-chain fatty acids and incorporation into lipid droplets was exclusive to the inner layer cytotrophoblast cells rather than the expected outer syncytiotrophoblast layer. Cytotrophoblast is a progenitor cell layer previously relegated to a repair role. As isolated cytotrophoblasts differentiated into syncytialized cells in culture, they weakened their lipid processing capacity. Syncytializing cells suppress previously active genes that regulate fatty-acid uptake (SLC27A2/FATP2, FABP4, ACSL5) and lipid metabolism (GPAT3, LPCAT3). We speculate that cytotrophoblast performs a previously unrecognized role in regulating placental fatty acid uptake and metabolism. PMID:27124483

  18. Expression of factors involved in the regulation of angiogenesis in the full-term human placenta: Effects of in vitro fertilization.

    PubMed

    Li, Chanjuan; Zhang, Yuan; Tang, Lisha; Zhao, Haijun; Gao, Chao; Gao, Li; Cui, Yugui; Liu, Jiayin

    2016-06-01

    The effects of assisted reproductive technologies (ARTs) on the safety of pregnancy and the resulting offspring remain controversial. Studies of placental functions, especially vasculogenesis and angiogenesis, in pregnancies established through ART are helpful for furthering our understanding of the safety of ART. This study compares the expression profiles of angiogenic factors in human term placentas obtained from natural (NAT) pregnancies vs. placentas obtained from pregnancies that resulted from ART. Term placentas were obtained from women who underwent an ART procedure (n=4), and these were compared with term placentas that were obtained from women who had experienced a spontaneous pregnancy (controls, n=4). An array analysis was performed using the Human Angiogenesis Antibody Array to detect 43 angiogenic factors and to identify which of these factors were differentially expressed between the two groups. The expression of six of these factors was greater in the ART group than in the NAT group. The levels of four of them, including vascular endothelial growth factor receptor-3 (VEGFR3), basic fibroblast growth factor (bFGF), interferon gamma (IFNG) and matrix metalloproteinase 1 (MMP1), were quantified using western blot analysis. These factors were examined using immunohistochemistry and microscopy in vascular endothelial cells or the cytoplasm and membranes of syncytiotrophoblast cells. Our finding that selected angiogenic factors exhibit altered expression profiles in ART placentas might be significant when evaluating ART safety. PMID:27288334

  19. Real-Time Tracking of BODIPY-C12 Long-Chain Fatty Acid in Human Term Placenta Reveals Unique Lipid Dynamics in Cytotrophoblast Cells

    PubMed Central

    Louey, Samantha; Varlamov, Oleg; Thornburg, Kent

    2016-01-01

    While the human placenta must provide selected long-chain fatty acids to support the developing fetal brain, little is known about the mechanisms underlying the transport process. We tracked the movement of the fluorescently labeled long-chain fatty acid analogue, BODIPY-C12, across the cell layers of living explants of human term placenta. Although all layers took up the fatty acid, rapid esterification of long-chain fatty acids and incorporation into lipid droplets was exclusive to the inner layer cytotrophoblast cells rather than the expected outer syncytiotrophoblast layer. Cytotrophoblast is a progenitor cell layer previously relegated to a repair role. As isolated cytotrophoblasts differentiated into syncytialized cells in culture, they weakened their lipid processing capacity. Syncytializing cells suppress previously active genes that regulate fatty-acid uptake (SLC27A2/FATP2, FABP4, ACSL5) and lipid metabolism (GPAT3, LPCAT3). We speculate that cytotrophoblast performs a previously unrecognized role in regulating placental fatty acid uptake and metabolism. PMID:27124483

  20. Endothelin A and B receptors change their expression levels during development of human placental villi.

    PubMed

    Cervar, M; Huppertz, B; Barth, S; Hahn, T; Weiss, U; Kaufmann, P; Desoye, G

    2000-01-01

    Endothelin receptors have recently been found in non-vascular tissues including the human placenta. The present study investigated developmental changes in location and expression levels of endothelin A and B receptors (ETA-R, ETB-R) in human placentae and isolated trophoblast by comparing first and third trimester tissues. In the first trimester all cells and tissues were immunolabelled for ETA-R and ETB-R, whereas in third trimester placentae the syncytiotrophoblast (ETA-R, ETB-R) and macrophages (ETA-R) were unstained. Immunoblotting for both receptors revealed up to three bands at 33-35, 50 and 75 kDa, respectively, which were differentially present in the first and third trimester. Pre-adsorption of antibodies with oligopeptides used for antigen-generation weakened the immunoreactions. ETA-R protein levels decreased (P< 0.05) in total villous tissue and isolated trophoblast, whereas ETB-R was unchanged. ETB-R transcripts (RT-PCR) prevailed in both stages and tissues, but in contrast to the protein levels its preponderance decreased from first trimester to term in villous tissue (P< 0.01), because of a four to five-fold increase in ETA-R and only a two-fold (P< 0.05) increase in ETB-R mRNA levels (P< 0.01). We conclude that ET receptor location, intracellular processing and expression levels in human villous tissue change between the first and third trimester. This may reflect changing functions of ET-1 during placental development. PMID:10940204

  1. Regulation of the syncytin-1 promoter in human astrocytes by multiple sclerosis-related cytokines

    SciTech Connect

    Mameli, Giuseppe . E-mail: viross@uniss.it; Astone, Vito; Khalili, Kamel; Serra, Caterina; Sawaya, Bassel E.; Dolei, Antonina

    2007-05-25

    Syncytin-1 has a physiological role during early pregnancy, as mediator of trophoblast fusion into the syncytiotrophoblast layer, hence allowing embryo implantation. In addition, its expression in nerve tissue has been proposed to contribute to the pathogenesis of multiple sclerosis (MS). Syncytin-1 is the env glycoprotein of the ERVWE1 component of the W family of human endogenous retroviruses (HERV), located on chromosome 7q21-22, in a candidate region for genetic susceptibility to MS. The mechanisms of ERVWE1 regulation in nerve tissue remain to be identified. Since there are correlations between some cytokines and MS outcome, we examined the regulation of the syncytin-1 promoter by MS-related cytokines in human U-87MG astrocytic cells. Using transient transfection assays, we observed that the MS-detrimental cytokines TNF{alpha}, interferon-{gamma}, interleukin-6, and interleukin-1 activate the ERVWE1 promoter, while the MS-protective interferon-{beta} is inhibitory. The effects of cytokines are reduced by the deletion of the cellular enhancer domain of the promoter that contains binding sites for several transcription factors. In particular, we found that TNF{alpha} had the ability to activate the ERVWE1 promoter through an NF-{kappa}B-responsive element located within the enhancer domain of the promoter. Electrophoretic mobility shift and ChIP assays showed that TNF{alpha} enhances the binding of the p65 subunit of NF-{kappa}B, to its cognate site within the promoter. The effect of TNF{alpha} is abolished by siRNA directed against p65. Taken together, these results illustrate a role for p65 in regulating the ERVWE1 promoter and in TNF{alpha}-mediated induction of syncytin-1 in multiple sclerosis.

  2. RhoGDI2 is expressed in human trophoblasts and involved in their migration by inhibiting the activation of RAC1.

    PubMed

    Liu, Sishi; Cui, Hong; Li, Qiuling; Zhang, Lijuan; Na, Quan; Liu, Caixia

    2014-04-01

    The invasion of placental trophoblast cells into the maternal decidua is an essential aspect of placental embedment. The process of placentation bears several striking similarities to tumor cell metastasis. However, trophoblastic migration during implantation and placentation is stringently controlled both in space and time. RhoGDI2 belongs to a family of Rho guanosine diphosphate dissociation inhibitors (RhoGDIs), and RhoGDI2 is a metastasis suppressor gene and a marker of aggressive human cancer. We evaluated whether RhoGDI2 has a physiological role in embryo implantation, particularly trophoblast migration. The mRNA and protein expression levels of RhoGDI2 were higher in term placentas compared with first-trimester placentas as detected by real-time PCR and Western blot. Immunohistochemical studies indicated that RhoGDI2 localized to the cytotrophoblast layer and extravillous trophoblast in first-trimester placentas and was distributed in the syncytiotrophoblast layers of term placentas. Overexpression of RhoGDI2 in HTR-8/SVneo cells was associated with reduced RAC1-guanosine triphosphate (GTP) levels and inhibited cell migration. Conversely, small interfering RNA-mediated downregulation of RhoGDI2 resulted in significantly increased RAC1-GTP levels. Altered RhoGDI2 expression had no significant effects on cell proliferation. In conclusion, RhoGDI2 inhibits trophoblast cell migration, and this function may involve suppression of RAC1 activation. PMID:24554735

  3. On the factors which contribute to thinning of the villous membrane in human placentae at high altitude. II. An increase in the degree of peripheralization of fetal capillaries.

    PubMed

    Jackson, M R; Mayhew, T M; Haas, J D

    1988-01-01

    The contribution made by fetal capillary peripheralization to the thinning of the villous membrane seen in human placentae from high-altitude pregnancies is examined by stereological methods. Variables characterizing the shape of the villous core and the spatial relationships between trophoblast and capillaries are quantified. They shed light on the relative importance of dynamic versus mechanistic processes of villous membrane attenuation. Highland villi differ from lowland villi in several ways. On average, they possess a thinner barrier due to closer approximation of capillaries to overlying trophoblast; in consequence, the villous core is more irregular in outline and its surface (that of the inner aspect of the trophoblast) exceeds in area that of the outer aspect of the trophoblast. These results suggest that the dynamic process (protoplasmic streaming within syncytiotrophoblast) cannot alone explain thinning of the villous membrane. A mechanistic process (capillary peripheralization and obtrusion into the trophoblastic epithelium) is sufficient to account for the differences observed, although the possibility that both processes operate concurrently cannot be discounted. This report completes a study into factors contributing to villous membrane thinning at high altitude. PMID:3362794

  4. Localization of major histocompatibility complex class I and II mRNA in human first-trimester chorionic villi by in situ hybridization.

    PubMed

    Lata, J A; Tuan, R S; Shepley, K J; Mulligan, M M; Jackson, L G; Smith, J B

    1992-04-01

    Maternal immune recognition of pregnancy occurs despite the nonexpression of classical major histocompatibility complex (MHC) antigenic determinants by chorionic villous trophoblast, which comprise the major surface area where maternal blood contacts fetal-derived cells. cDNA-mRNA in situ hybridization was used to probe expression of transcripts corresponding to nonpolymorphic MHC determinants in first-trimester chorionic villus samples. The HLA-B7 probe hybridization signals were localized to syncytiotrophoblast and to cells of the mesenchyme but not to villous cytotrophoblast. HLA-G mRNA was found only in syncytiotrophoblast. A DR beta clone hybridized to both villous cytotrophoblast and syncytiotrophoblast. The results suggest that expression of trophoblast class I and class II determinants early in gestation (10 wk) may be regulated by posttranscriptional events. This also suggests the potential for maternal antifetal alloimmune responses. PMID:1552281

  5. Global protein synthesis in human trophoblast is resistant to inhibition by hypoxia

    PubMed Central

    Williams, S.F.; Fik, E.; Zamudio, S.; Illsley, N.P.

    2012-01-01

    Placental growth and function depend on syncytial cell processes which require the continuing synthesis of cellular proteins. The substantial energy demands of protein synthesis are met primarily from oxidative metabolism. Although the responses of individual proteins produced by the syncytiotrophoblast to oxygen deprivation have been investigated previously, there is no information available on global protein synthesis in syncytiotrophoblast under conditions of hypoxia. These studies were designed to test the hypothesis that syncytial protein synthesis is decreased in a dose-dependent manner by hypoxia. Experiments were performed to measure amino acid incorporation into proteins in primary syncytiotrophoblast cells exposed to oxygen concentrations ranging from 0 to 10%. Compared to cells exposed to normoxia (10% O2), no changes were observed following exposure to 5% or 3% O2, but after exposure to 1% O2, protein synthesis after 24 and 48 h decreased by 24% and 23% and with exposure to 0% O2, by 65% and 50%. As a consequence of these results, we hypothesized that global protein synthesis in conditions of severe hypoxia was being supported by glucose metabolism. Additional experiments were performed therefore to examine the role of glucose in supporting protein synthesis. These demonstrated that at each oxygen concentration there was a significant, decreasing linear trend in protein synthesis as glucose concentration was reduced. Under conditions of near-anoxia and in the absence of glucose, protein synthesis was reduced by >85%. Even under normoxic conditions (defined as 10% O2) and in the presence of oxidative substrates, reductions in glucose were accompanied by decreases in protein synthesis. These experiments demonstrate that syncytiotrophoblast cells are resistant to reductions in protein synthesis at O2 concentrations greater than 1%. This could be explained by our finding that a significant fraction of protein synthesis in the syncytiotrophoblast is

  6. The psychoactive compound of Cannabis sativa, Δ(9)-tetrahydrocannabinol (THC) inhibits the human trophoblast cell turnover.

    PubMed

    Costa, M A; Fonseca, B M; Marques, F; Teixeira, N A; Correia-da-Silva, G

    2015-08-01

    The noxious effects of cannabis consumption for fertility and pregnancy outcome are recognized for years. Its consumption during gestation is associated with alterations in foetal growth, low birth weight and preterm labor. The main psychoactive molecule of cannabis, Δ(9)-tetrahydrocannabinol (THC) impairs the production of reproductive hormones and is also able to cross the placenta barrier. However, its effect on the main placental cells, the trophoblasts, are unknown. Actually, the role of THC in cell survival/death of primary human cytotrophoblasts (CTs) and syncytiotrophoblasts (STs) and in the syncytialization process remains to be explored. Here, we show that THC has a dual effect, enhancing MTT metabolism at low concentrations, whereas higher doses decreased cell viability, on both trophoblast phenotypes, though the effects on STs were more evident. THC also diminished the generation of oxidative and nitrative stress and the oxidized form of glutathione, whereas the reduced form of this tripeptide was increased, suggesting that THC prevents ST cell death due to an antioxidant effect. Moreover, this compound enhanced the mitochondrial function of STs, as observed by the increased MTT metabolism and intracellular ATP levels. These effects were independent of cannabinoid receptors activation. Besides, THC impaired CT differentiation into STs, since it decreased the expression of biochemical and morphological biomarkers of syncytialization, through a cannabinoid receptor-dependent mechanism. Together, these results suggest that THC interferes with trophoblast turnover, preventing trophoblast cell death and differentiation, and contribute to disclose the cellular mechanisms that lead to pregnancy complications in women that consume cannabis-derived drugs during gestation. PMID:26070387

  7. Regulation of the human endogenous retroviral Syncytin-1 and cell-cell fusion by the nuclear hormone receptors PPARγ/RXRα in placentogenesis.

    PubMed

    Ruebner, Matthias; Langbein, Manuela; Strissel, Pamela L; Henke, Christine; Schmidt, Doreen; Goecke, Tamme W; Faschingbauer, Florian; Schild, Ralf L; Beckmann, Matthias W; Strick, Reiner

    2012-07-01

    Cytotrophoblast (CT) cell fusion into a syncytiotrophoblast is obligatory for placentation and mediated by the human endogenous retrovirus (HERV)-W envelope gene Syncytin-1. Abnormal placentation is associated with preeclampsia (PE), HELLP and intrauterine growth restriction (IUGR). In placentogenesis, the MAP-kinase p38α regulates PPARγ/RXRα signaling and target genes, like leptin, resistin, ABCG2, and hCG. The aim of this study was to analyze PPARγ/RXRα signaling and target gene regulation using primary CT cultures, the trophoblastic cell line BeWo and placental tissues from patients with normal and abnormal placentation. CT from four different human control placentae and BeWo cells demonstrated that Syncytin-1, other signaling members and CT cell fusions were regulated with PPARγ/RXRα activators troglitazone and 9-cis retinoic acid, via protein kinase A and p38α inhibition. Significant discordant regulations between CTs and BeWo were found. Two PPARγ/RXRα-response-elements from upstream regulatory elements and the 5'LTR of HERV-W were confirmed with DNA-protein binding assays using nuclear extracts and recombinant PPARγ/RXRα proteins. These promoter elements were validated with luciferase assays in the presence of PPARγ/RXRα modulators. Furthermore, troglitazone or 9-cis retinoic acid treatment of siRNA-PPARγ and siRNA-RXRα transfected BeWo cells proved the requirement of these proteins for Syncytin-1 regulation. Thirty primary abnormal placentae from PE, HELLP and IUGR patients compared to 10 controls showed significant deregulation of leptin RNA and protein, p38α, phospho-p38α, PPARγ, ABCG2, INSL4 and Syncytin-1. Our study characterized PPARγ/RXRα signaling in human CT and cell fusions identifying Syncytin-1 as a new target gene. Based on these results, a disturbed PPARγ/RXRα pathway could contribute to pathological human pregnancies. PMID:22573555

  8. Increased ubiquitination and reduced plasma membrane trafficking of placental amino acid transporter SNAT-2 in human IUGR.

    PubMed

    Chen, Yi-Yung; Rosario, Fredrick J; Shehab, Majida Abu; Powell, Theresa L; Gupta, Madhulika B; Jansson, Thomas

    2015-12-01

    Placental amino acid transport is decreased in intrauterine growth restriction (IUGR); however, the underlying mechanisms remain largely unknown. We have shown that mechanistic target of rapamycin (mTOR) signalling regulates system A amino acid transport by modulating the ubiquitination and plasma membrane trafficking of sodium-coupled neutral amino acid transporter 2 (SNAT-2) in cultured primary human trophoblast cells. We hypothesize that IUGR is associated with (1) inhibition of placental mTORC1 and mTORC2 signalling pathways, (2) increased amino acid transporter ubiquitination in placental homogenates and (3) decreased protein expression of SNAT-2 in the syncytiotrophoblast microvillous plasma membrane (MVM). To test this hypothesis, we collected placental tissue and isolated MVM from women with pregnancies complicated by IUGR (n=25) and gestational age-matched women with appropriately grown control infants (n=19, birth weights between the twenty-fifth to seventy-fifth percentiles). The activity of mTORC1 and mTORC2 was decreased whereas the protein expression of the ubiquitin ligase NEDD4-2 (neural precursor cell expressed developmentally down-regulated protein 4-2; +72%, P<0.0001) and the ubiquitination of SNAT-2 (+180%, P<0.05) were increased in homogenates of IUGR placentas. Furthermore, IUGR was associated with decreased system A amino acid transport activity (-72%, P<0.0001) and SNAT-1 (-42%, P<0.05) and SNAT-2 (-31%, P<0.05) protein expression in MVM. In summary, these findings are consistent with the possibility that decreased placental mTOR activity causes down-regulation of placental system A activity by shifting SNAT-2 trafficking towards proteasomal degradation, thereby contributing to decreased fetal amino acid availability and restricted fetal growth in IUGR. PMID:26374858

  9. Human See, Human Do.

    ERIC Educational Resources Information Center

    Tomasello, Michael

    1997-01-01

    A human demonstrator showed human children and captive chimpanzees how to drag food or toys closer using a rakelike tool. One side of the rake was less efficient than the other for dragging. Chimps tried to reproduce results rather than methods while children imitated and used the more efficient rake side. Concludes that imitation leads to…

  10. Transfer of PAMAM Dendrimers across Human Placenta: Prospects of Its Use as Drug Carrier During Pregnancy

    PubMed Central

    Menjoge, Anupa R.; Rinderknecht, Amber; Navath, Raghavendra S.; Faridnia, Masoud; Kim, Chong J.; Romero, Roberto; Miller, Richard K.; Kannan, Rangaramanujam M.

    2011-01-01

    Dendrimers offer significant potential as nanocarriers for targeted delivery of drugs and imaging agents. The objectives of this study were to evaluate the transplacental transport, kinetics and biodistribution of PAMAM dendrimers ex-vivo across the human placenta in comparison with antipyrine, a freely diffusible molecule, using dually perfused re-circulating term human placental lobules. The purpose of this study is to determine if dendrimers as drug carriers can be used to design drug delivery systems directed at selectively treating either the mother or the fetus. The transplacental transfers of fluorescently (Alexa 488) tagged PAMAM dendrimer (16 kDa) and antipyrine (188 Da) from maternal to fetal circulation were measured using HPLC/dual UV and fluorescent detector (sensitivity of 10 ng / mL for dendrimer and 100 ng /mL for antipyrine respectively). Cmax for the dendrimer-Alexa (DA) in maternal perfusate (Tmax = 15min) was 18 times higher than in the fetal perfusate and never equilibrated with the maternal perfusate during 5.5 hours of perfusion (n=4). DA exhibited a significant but low transplacental transport of ~2.26 ± 0.12 μg / mL during 5.5 hours, where the mean transplacental transfer was 0.84 ±0.11 % of the total maternal concentration and the feto-maternal ratio as percent was 0.073% ± 0.02. The biochemical and physiological analysis of the placentae perfused with DA demonstrated normal function throughout the perfusion. The immunofluorescence histochemistry confirmed that the biodistribution of DA in perfused placenta was sparsely dispersed, and when noted was principally seen in the inter-villous spaces and outer rim of the villous branches. In a few cases, DA was found internalized and localized in nuclei and cytoplasm of syncytiotrophoblast and inside the villous core; however, DA was mostly absent from the villous capillaries. In conclusion, the PAMAM dendrimers exhibited a low rate of transfer from maternal to the fetal side across the

  11. Isolation and Characterization of Human Trophoblast Side-Population (SP) Cells in Primary Villous Cytotrophoblasts and HTR-8/SVneo Cell Line

    PubMed Central

    Takao, Tomoka; Asanoma, Kazuo; Kato, Kiyoko; Fukushima, Kotaro; Tsunematsu, Ryosuke; Hirakawa, Toshio; Matsumura, Sueo; Seki, Hiroyuki; Takeda, Satoru; Wake, Norio

    2011-01-01

    Recently, numerous studies have identified that immature cell populations including stem cells and progenitor cells can be found among “side-population” (SP) cells. Although SP cells isolated from some adult tissues have been reported elsewhere, isolation and characterization of human trophoblast SP remained to be reported. In this study, HTR-8/SVneo cells and human primary villous cytotrophoblasts (vCTBs) were stained with Hoechst 33342 and SP and non-SP (NSP) fractions were isolated using a cell sorter. A small population of SP cells was identified in HTR-8/SVneo cells and in vCTBs. SP cells expressed several vCTB-specific markers and failed to express syncytiotrophoblast (STB) or extravillous cytotrophopblast (EVT)-specific differentiation markers. SP cells formed colonies and proliferated on mouse embryonic fibroblast (MEF) feeder cells or in MEF conditioned medium supplemented with heparin/FGF2, and they also showed long-term repopulating property. SP cells could differentiate into both STB and EVT cell lineages and expressed several differentiation markers. Microarray analysis revealed that IL7R and IL1R2 were exclusively expressed in SP cells and not in NSP cells. vCTB cells sorted as positive for both IL7R and IL1R2 failed to express trophoblast differentiation markers and spontaneously differentiated into both STB and EVT in basal medium. These features shown by the SP cells suggested that IL7R and IL1R2 are available as markers to detect the SP cells and that vCTB progenitor cells and trophoblast stem cells were involved in the SP cell population. PMID:21760941

  12. Localization and regulation of the human very low density lipoprotein/apolipoprotein-E receptor: trophoblast expression predicts a role for the receptor in placental lipid transport.

    PubMed

    Wittmaack, F M; Gåfvels, M E; Bronner, M; Matsuo, H; McCrae, K R; Tomaszewski, J E; Robinson, S L; Strickland, D K; Strauss, J F

    1995-01-01

    The very low density lipoprotein/apolipoprotein-E receptor (VLDLR) is the newest member of the low density lipoprotein receptor (LDLR) family. Very little is known about VLDLR localization and regulation. Immunohistochemical analysis of human placenta with a specific polyclonal antibody detected VLDLR in syncytiotrophoblast and intermediate trophoblast cells. VLDLR transcripts were also localized in these cells by in situ hybridization histochemistry. In addition, VLDLR messenger RNA (mRNA) was detected in villous core endothelial cells and cells appearing to be Hofbauer cells. Northern blot analysis of placenta revealed a 2.6-fold increase in VLDLR mRNA at term compared to that in the first trimester. The regulation of VLDLR expression was studied in JEG-3 and BeWo choriocarcinoma cells, two trophoblast-derived cell lines. Treatment of these cells with 8-bromo-cAMP caused a profound suppression of VLDLR message, whereas LDLR transcripts were increased. Incubation of JEG-3 cells with 25-hydroxycholesterol did not lead to sterol negative feedback on VLDLR gene expression, unlike LDLR mRNA, which declined markedly. Insulin (200 mg/L) up-regulated VLDLR message in JEG-3 cells 2-fold, as did the fibrate hypolipidemic drug, clofibric acid. We conclude that 1) VLDLR is expressed in human placental trophoblast cells in a pattern consistent with a role in placental lipid transport; 2) VLDLR expression is high at term relative to that in the first trimester; and 3) the trophoblast VLDLR is subject to down-regulation by cAMP and up-regulation by insulin and fibrate hypolipidemic drugs. PMID:7828550

  13. Human chorionic gonadotropin: Different glycoforms and biological activity depending on its source of production.

    PubMed

    Fournier, Thierry

    2016-06-01

    Human chorionic gonadotropin (hCG) is the first hormonal message from the placenta to the mother. It is detectable in maternal blood two days after implantation and behaves like a super LH agonist stimulating progesterone secretion by the corpus luteum. In addition to maintaining the production of progesterone until the placenta itself produces it, hCG also has a role in myometrial quiescence and local immune tolerance. Specific to humans, hCG is a complex glycoprotein composed of two highly glycosylated subunits. The α-subunit is identical to the pituitary gonadotropin hormones (LH, FSH, TSH), contains two N-glycosylation sites, and is encoded by a single gene (CGA). By contrast, the β-subunits are distinct for each hormones and confer both receptor and biological specificity, although LH and hCG bind to the same receptor (LH/CG-R). The hCG ß-subunit is encoded by a cluster of genes (CGB) and contains two sites of N-glycosylation and four sites of O-glycosylation. The hCG glycosylation state varies with the stage of pregnancy, its source of production and in the pathology. It is well established that hCG is mainly secreted into maternal blood, where it peaks at 8-10weeks of gestation (WG), by the syncytiotrophoblast (ST), which represents the endocrine tissue of the human placenta. The invasive extravillous trophoblast (iEVT) also secretes hCG, and in particular hyperglycosylated forms of hCG (hCG-H) also produced by choriocarcinoma cells. In maternal blood, hCG-H is elevated during early first trimester corresponding to the trophoblastic cell invasion process and then decreases. In addition to its endocrine role, hCG has autocrine and paracrine roles. It promotes formation of the ST and angiogenesis through LH/CG-R but has no effect on trophoblast invasion in vitro. By contrast, hCG-H stimulates trophoblast invasion and angiogenesis by interacting with the TGFß receptor in a LH/CG-R independent signalling pathway. hCG is largely used in antenatal screening

  14. Human Development, Human Evolution.

    ERIC Educational Resources Information Center

    Smillie, David

    One of the truly remarkable events in human evolution is the unprecedented increase in the size of the brain of "Homo" over a brief span of 2 million years. It would appear that some significant selective pressure or opportunity presented itself to this branch of the hominid line and caused a rapid increase in the brain, introducing a wholly new…

  15. A Positive Feedback Loop between Glial Cells Missing 1 and Human Chorionic Gonadotropin (hCG) Regulates Placental hCGβ Expression and Cell Differentiation

    PubMed Central

    Cheong, Mei-Leng; Wang, Liang-Jie; Chuang, Pei-Yun; Chang, Ching-Wen; Lee, Yun-Shien; Lo, Hsiao-Fan; Tsai, Ming-Song

    2015-01-01

    Human chorionic gonadotropin (hCG) is composed of a common α subunit and a placenta-specific β subunit. Importantly, hCG is highly expressed in the differentiated and multinucleated syncytiotrophoblast, which is formed via trophoblast cell fusion and stimulated by cyclic AMP (cAMP). Although the ubiquitous activating protein 2 (AP2) transcription factors TFAP2A and TFAP2C may regulate hCGβ expression, it remains unclear how cAMP stimulates placenta-specific hCGβ gene expression and trophoblastic differentiation. Here we demonstrated that the placental transcription factor glial cells missing 1 (GCM1) binds to a highly conserved promoter region in all six hCGβ paralogues by chromatin immunoprecipitation-on-chip (ChIP-chip) analyses. We further showed that cAMP stimulates GCM1 and the CBP coactivator to activate the hCGβ promoter through a GCM1-binding site (GBS1), which also constitutes a previously identified AP2 site. Given that TFAP2C may compete with GCM1 for GBS1, cAMP enhances the association between the hCGβ promoter and GCM1 but not TFAP2C. Indeed, the hCG-cAMP-protein kinase A (PKA) signaling pathway also stimulates Ser269 and Ser275 phosphorylation of GCM1, which recruits CBP to mediate GCM1 acetylation and stabilization. Consequently, hCG stimulates the expression of GCM1 target genes, including the fusogenic protein syncytin-1, to promote placental cell fusion. Our study reveals a positive feedback loop between GCM1 and hCG regulating placental hCGβ expression and cell differentiation. PMID:26503785

  16. New discoveries on the biology and detection of human chorionic gonadotropin

    PubMed Central

    Cole, Laurence A

    2009-01-01

    Human chorionic gonadotropin (hCG) is a glycoprotein hormone comprising 2 subunits, alpha and beta joined non covalently. While similar in structure to luteinizing hormone (LH), hCG exists in multiple hormonal and non-endocrine agents, rather than as a single molecule like LH and the other glycoprotein hormones. These are regular hCG, hyperglycosylated hCG and the free beta-subunit of hyperglycosylated hCG. For 88 years regular hCG has been known as a promoter of corpus luteal progesterone production, even though this function only explains 3 weeks of a full gestations production of regular hCG. Research in recent years has explained the full gestational production by demonstration of critical functions in trophoblast differentiation and in fetal nutrition through myometrial spiral artery angiogenesis. While regular hCG is made by fused villous syncytiotrophoblast cells, extravillous invasive cytotrophoblast cells make the variant hyperglycosylated hCG. This variant is an autocrine factor, acting on extravillous invasive cytotrophoblast cells to initiate and control invasion as occurs at implantation of pregnancy and the establishment of hemochorial placentation, and malignancy as occurs in invasive hydatidiform mole and choriocarcinoma. Hyperglycosylated hCG inhibits apoptosis in extravillous invasive cytotrophoblast cells promoting cell invasion, growth and malignancy. Other non-trophoblastic malignancies retro-differentiate and produce a hyperglycosylated free beta-subunit of hCG (hCG free beta). This has been shown to be an autocrine factor antagonizing apoptosis furthering cancer cell growth and malignancy. New applications have been demonstrated for total hCG measurements and detection of the 3 hCG variants in pregnancy detection, monitoring pregnancy outcome, determining risk for Down syndrome fetus, predicting preeclampsia, detecting pituitary hCG, detecting and managing gestational trophoblastic diseases, diagnosing quiescent gestational trophoblastic

  17. Human Health

    MedlinePlus

    ... effects of climate change Video not supported Human Health Climate change threatens human health and well-being ... Copy link to clipboard Key Message: Wide-ranging Health Impacts Climate change threatens human health and well- ...

  18. Computational Fluid Dynamic Simulations of Maternal Circulation: Wall Shear Stress in the Human Placenta and Its Biological Implications

    PubMed Central

    Lecarpentier, E.; Bhatt, M.; Bertin, G. I.; Deloison, B.; Salomon, L. J.; Deloron, P.; Fournier, T.; Barakat, A. I.; Tsatsaris, V.

    2016-01-01

    Introduction In the human placenta the maternal blood circulates in the intervillous space (IVS). The syncytiotrophoblast (STB) is in direct contact with maternal blood. The wall shear stress (WSS) exerted by the maternal blood flow on the STB has not been evaluated. Our objective was to determine the physiological WSS exerted on the surface of the STB during the third trimester of pregnancy. Material and Methods To gain insight into the shear stress levels that the STB is expected to experience in vivo, we have formulated three different computational models of varying levels of complexity that reflect different physical representations of the IVS. Computations of the flow fields in all models were performed using the CFD module of the finite element code COMSOL Multiphysics 4.4. The mean velocity of maternal blood in the IVS during the third trimester was measured in vivo with dynamic MRI (0.94±0.14 mm.s-1). To investigate if the in silico results are consistent with physiological observations, we studied the cytoadhesion of human parasitized (Plasmodium falciparum) erythrocytes to primary human STB cultures, in flow conditions with different WSS values. Results The WSS applied to the STB is highly heterogeneous in the IVS. The estimated average values are relatively low (0.5±0.2 to 2.3±1.1 dyn.cm-2). The increase of WSS from 0.15 to 5 dyn.cm-2 was associated with a significant decrease of infected erythrocyte cytoadhesion. No cytoadhesion of infected erythrocytes was observed above 5 dyn.cm-2 applied for one hour. Conclusion Our study provides for the first time a WSS estimation in the maternal placental circulation. In spite of high maternal blood flow rates, the average WSS applied at the surface of the chorionic villi is low (<5 dyn.cm-2). These results provide the basis for future physiologically-relevant in vitro studies of the biological effects of WSS on the STB. PMID:26815115

  19. Design, Construction, and Evaluation of a Specific Chimeric Antigen To Diagnose Chagasic Infection

    PubMed Central

    Aguirre, Sebastián; Silber, Ariel M.; Brito, Maria Edileuza F.; Ribone, María E.; Lagier, Claudia M.; Marcipar, Iván S.

    2006-01-01

    Chagas' disease is routinely diagnosed by detecting specific antibodies (Abs) using serological methods. The methodology has the drawback of potential cross-reactions with Abs raised during other infectious and autoimmune diseases (AID). Fusion of DNA sequences encoding antigenic proteins is a versatile tool to engineer proteins to be used as sensitizing elements in serological tests. A synthetic gene encoding a chimeric protein containing the C-terminal region of C29 and the N-terminal region of TcP2β was constructed. A 236-serum panel, composed of 104 reactive and 132 nonreactive sera to Chagas' disease, was used to evaluate the performance of the chimera. Among the nonreactive sera, 65 were from patients with AID (systemic lupus erythematosus and rheumatoid arthritis) or patients infected with Leishmania brasiliensis, Brucella abortus, Streptococcus pyogenes, or Toxoplasma gondii. The diagnostic performances of the complete TcP2β (TcP2βFL) and its N-terminal region (TcP2βN) were evaluated. TcP2βFL showed unspecific recognition toward leishmaniasis (40%) and AID Abs (58%), while TcP2βN showed no unspecific recognition. The diagnostic utility of the chimera was evaluated by analyzing reactivity and comparing the results with those obtained with TcP2βN. The chimera reactivity was higher than that of the peptide fractions (0.874 versus 0.564 optical density, P = 0.0017). The detectability and specificity were both 100% for the whole serum panel tested. We conclude that the obtained chimera shows an improved selectivity and sensitivity compared with other ones previously reported, therefore displaying an optimized performance for Trypanosoma cruzi infection diagnosis. PMID:17021107

  20. [Detection of Trypanosoma cruzi DNA in the placenta and fetuses of mice with Chagasic acute infection].

    PubMed

    Alarcón, Maritza; Pérez, Mary Carmen; Villarreal, Juana; Araujo, Sonia; Goncalves, Loredana; González, Anajulia; Moreno, Elio; Lugo-Yarbuh, Ana

    2009-09-01

    The objective of the present study was to detect the presence of Trypanosoma cruzi DNA in the placenta and fetal tissues of NMRI mice (Mus musculus) inoculated with 22 x 10(3) trypomastigotes metacyclic of the M/HOM/BRA/53/Y strain by intraperitoneal route. Mice were pregnant in the acute phase of the infection. The course of patent parasitemia by T. cruzi was evaluated before mating and during pregnancy. At day twenty of gestation, animals were sacrificed and the fetuses and their placentas were removed to evaluate T. cruzi infection. Samples of fetal placenta, heart and skeletal muscle were fixed in 10%, formalin, included in paraffin and stained with hematoxilin and eosin (HE). The histopathological study of sections of fetal tissues revealed inflammatory infiltrates with mononuclear and polymorphonuclear cells and without parasitism in these tissues. The amplification of T. cruzi DNA by Polymerase Chain Reaction (PCR) showed a positive reaction in 18% of placental tissue of pregnant infected mice. The samples of heart and skeletal muscle of the fetuses of mothers infected with T. cruzi did not show the presence T. cruzi DNA. The placenta and skeletal muscle of the fetuses analyzed by Peroxidase anti Peroxidase inmunostaining showed T. cruzi antigens in those tissues. Negative results by PCR in fetal tissues might be related with the virulence and tropism associated with the biological and genetic characteristic Of the T. cruzi strain used in the experimental infection of female mice. PMID:19961056

  1. Novel 3-nitrotriazole-based amides and carbinols as bifunctional anti-Chagasic agents

    PubMed Central

    Papadopoulou, Maria V.; Bloomer, William D.; Lepesheva, Galina I.; Rosenzweig, Howard S.; Kaiser, Marcel; Aguilera-Venegas, Benjamín; Wilkinson, Shane R.; Chatelain, Eric; Ioset, Jean-Robert

    2015-01-01

    3-Nitro-1H-1,2,4-triazole-based amides with a linear, rigid core and 3-nitrotriazole-based fluconazole analogs were synthesized as dual functioning antitrypanosomal agents. Such compounds are excellent substrates for type I nitroreductase (NTR) located in the mitochondrion of trypanosomatids and, at the same time, act as inhibitors of the sterol 14α-demethylase (T. cruzi CYP51) enzyme. Because combination treatments against parasites are often superior to monotherapy, we believe that this emerging class of bifunctional compounds may introduce a new generation of antitrypanosomal drugs. In the present work, the synthesis and in vitro and in vivo evaluation of such compounds is discussed. PMID:25580906

  2. Use of venoarterial extracorporeal membrane oxygenation in fulminant chagasic myocarditis as a bridge to heart transplant

    PubMed Central

    Durães, André Rodrigues; Figueira, Fernando Augusto Marinho dos Santos; Lafayette, André Rabelo; Martins, Juliana de Castro Solano; Juliano Cavalcante de, Sá

    2015-01-01

    A 17-year-old Brazilian male presented with progressive dyspnea for 15 days, worsening in the last 24 hours, and was admitted in respiratory failure and cardiogenic shock, with multiple organ dysfunctions. Echocardiography showed a left ventricle ejection fraction of 11%, severe diffuse hypokinesia, and a systolic pulmonary artery pressure of 50mmHg, resulting in the need for hemodynamic support with dobutamine (20mcg/kg/min) and noradrenaline (1.7mcg/kg/min). After 48 hours with no clinical or hemodynamic improvement, an extracorporeal membrane oxygenation was implanted. The patient presented with hemodynamic, systemic perfusion and renal and liver function improvements; however, his cardiac function did not recover after 72 hours, and he was transfer to another hospital. Air transport was conducted from Salvador to Recife in Brazil. A heart transplant was performed with rapid recovery of both liver and kidney functions, as well as good graft function. Histopathology of the explanted heart showed chronic active myocarditis and amastigotes of Trypanosoma cruzi. The estimated global prevalence of T. cruzi infections declined from 18 million in 1991, when the first regional control initiative began, to 5.7 million in 2010. Myocarditis is an inflammatory disease due to infectious or non-infectious conditions. Clinical manifestation is variable, ranging from subclinical presentation to refractory heart failure and cardiogenic shock. Several reports suggest that the use of extracorporeal membrane oxygenation in patients presenting with severe refractory myocarditis is a potential bridging therapy to heart transplant when there is no spontaneous recovery of ventricular function. In a 6-month follow-up outpatient consult, the patient presented well and was asymptomatic. PMID:26761479

  3. Current and emerging therapeutic options for the treatment of chronic chagasic cardiomyopathy

    PubMed Central

    Muratore, Claudio A; Baranchuk, Adrian

    2010-01-01

    Chagas’ disease is an endemic disease in Latin America caused by a unicellular parasite (Trypanosoma cruzi) that affects almost 18 million people. This condition involves the heart, causing heart failure, arrhythmias, heart block, thromboembolism, stroke, and sudden death. In this article, we review the current and emerging treatment of Chagas’ cardiomyopathy focusing mostly on management of heart failure and arrhythmias. Heart failure therapeutical options including drugs, stem cells and heart transplantation are revised. Antiarrhythmic drugs, catheter ablation, and intracardiac devices are discussed as well. Finally, the evidence for a potential role of specific antiparasitic treatment for the prevention of cardiovascular disease is reviewed. PMID:20730015

  4. Human Trafficking

    MedlinePlus

    ... to debt bondage or peonage in which traffickers demand labor as a means repayment for a real ... human smuggling are two separate crimes under federal law. There are several important differences between them. Human ...

  5. Human Trafficking

    MedlinePlus

    ... TRAFFICKING (English) Listen < Back to Search FACT SHEET: HUMAN TRAFFICKING (English) Published: August 2, 2012 Topics: Public Awareness , ... organizations that protect and serve trafficking victims. National Human Trafficking Resource Center at 1.888.373.7888 Last ...

  6. Localization of transforming growth factor-beta at the human fetal-maternal interface: role in trophoblast growth and differentiation.

    PubMed

    Graham, C H; Lysiak, J J; McCrae, K R; Lala, P K

    1992-04-01

    We examined the localization of transforming growth factor (TGF)-beta in first-trimester and term human decidua and chorionic villi and explored the role of this factor on the proliferation and differentiation of cultured trophoblast cells. Two antibodies, 1D11.16.8, a mouse monoclonal neutralizing antibody capable of recognizing both TGF-beta 1 and TGF-beta 2 and CL-B1/29, a rabbit polyclonal antibody capable of recognizing TGF-beta 2, were used to immunolocalize TGF-beta in fixed, paraffin-embedded, or fixed, frozen sections of placenta and decidua, providing similar results. Intense labeling was observed in the extracellular matrix (ECM) of the first-trimester decidua and cytoplasm of term decidual cells. Syncytiotrophoblast cell cytoplasm as well as the ECM in the core of the chorionic villi of both first-trimester and term placentas exhibited a moderate degree of labeling. Strong cytoplasmic labeling was observed in the cytotrophoblastic shell of the term placenta. To examine the role of TGF-beta on trophoblast proliferation and differentiation, early passage cultures of first-trimester and primary cultures of term trophoblast cells were established and characterized on the basis of numerous immunocytochemical and functional markers. These cells expressed cytokeratin, placental alkaline phosphatase, urokinase-type plasminogen activator, and pregnancy-specific beta glycoprotein, but not factor VIII or 63D3; they also produced hCG and collagenase type IV. Exposure of first-trimester trophoblast cultures to TGF-beta 1 significantly inhibited proliferation in a dose-dependent manner. An antiproliferative effect was also noted in the presence of TGF-beta 2. These effects were abrogated in the presence of the neutralizing anti-TGF-beta antibody (1D11.16.8) in a concentration-dependent manner. In a 3-day culture, exogenous TGF-beta 1 stimulated formation of multinucleated cells by the first trimester as well as term trophoblast cells. Addition of neutralizing anti

  7. Vitamin C Supplementation Ameliorates the Adverse Effects of Nicotine on Placental Hemodynamics and Histology in Non-Human Primates

    PubMed Central

    Lo, Jamie O.; Schabel, Matthias C.; Roberts, Victoria H.J.; Morgan, Terry K.; Rasanen, Juha P.; Kroenke, Christopher D.; Shoemaker, Ms. Sophie R.; Spindel, Eliot R.; Frias, Antonio E.

    2015-01-01

    Objective We previously demonstrated that prenatal nicotine exposure decreases neonatal pulmonary function in non-human primates (NHP) and maternal Vitamin C supplementation attenuates these deleterious effects. However, nicotine’s effect on placental perfusion and development is not fully understood. This study utilizes non-invasive imaging techniques and histological analysis in a NHP model to test the hypothesis that prenatal nicotine exposure adversely effects placental hemodynamics and development, but is ameliorated by Vitamin C. Study Design Time-mated macaques (n=27) in 4 treatment groups: control (n=5), nicotine only (n=4), Vitamin C only (n=9), and nicotine plus Vitamin C (n=9). Nicotine animals received 2mg/kg/day of nicotine bitartrate (~0.7mg/kg/day free nicotine levels in pregnant human smokers) from days 26–160 (term, 168 days). Vitamin C groups received ascorbic acid at 50, 100 or 250mg/kg/day with or without nicotine. All underwent placental Dynamic Contrast-Enhanced MRI (DCE-MRI) at 135–140 days and Doppler ultrasound at 155 days to measure uterine artery and umbilical vein velocimetry and diameter to calculate uterine artery volume blood flow (cQuta) and placental volume blood flow (cQuv). Animals were delivered by cesarean section at 160 days. A novel DCE-MRI protocol was utilized to calculate placental perfusion from maternal spiral arteries. Placental tissue was processed for histopathology. Results Placental volume blood flow (cQuv) was significantly reduced in nicotine only animals compared with controls and nicotine plus Vitamin C groups (p=0.03). Maternal placental blood flow was not different between experimental groups by DCE-MRI ranging from 0.75–1.94 ml/ml/min (p=0.93). Placental histology showed increased numbers of villous cytotrophoblast cell islands (p<0.05) and increased syncytiotrophoblast sprouting (p<0.001) in nicotine only animals, which was mitigated by Vitamin C. Conclusion Prenatal nicotine exposure significantly

  8. Human Issues in Human Rights

    ERIC Educational Resources Information Center

    Kates, Robert W.

    1978-01-01

    Presents the report of the National Academy of Sciences' Committee in Human Rights which seeks to ease the plight of individual scientists, engineers, and medical personnel suffering severe repression. Case studies of instances of negligence of human rights are provided. (CP)

  9. Placental Syncytium Forms a Biophysical Barrier against Pathogen Invasion

    PubMed Central

    Zeldovich, Varvara B.; Clausen, Casper H.; Bradford, Emily; Fletcher, Daniel A.; Maltepe, Emin; Robbins, Jennifer R.; Bakardjiev, Anna I.

    2013-01-01

    Fetal syncytiotrophoblasts form a unique fused multinuclear surface that is bathed in maternal blood, and constitutes the main interface between fetus and mother. Syncytiotrophoblasts are exposed to pathogens circulating in maternal blood, and appear to have unique resistance mechanisms against microbial invasion. These are due in part to the lack of intercellular junctions and their receptors, the Achilles heel of polarized mononuclear epithelia. However, the syncytium is immune to receptor-independent invasion as well, suggesting additional general defense mechanisms against infection. The difficulty of maintaining and manipulating primary human syncytiotrophoblasts in culture makes it challenging to investigate the cellular and molecular basis of host defenses in this unique tissue. Here we present a novel system to study placental pathogenesis using murine trophoblast stem cells (mTSC) that can be differentiated into syncytiotrophoblasts and recapitulate human placental syncytium. Consistent with previous results in primary human organ cultures, murine syncytiotrophoblasts were found to be resistant to infection with Listeria monocytogenes via direct invasion and cell-to-cell spread. Atomic force microscopy of murine syncytiotrophoblasts demonstrated that these cells have a greater elastic modulus than mononuclear trophoblasts. Disruption of the unusually dense actin structure – a diffuse meshwork of microfilaments - with Cytochalasin D led to a decrease in its elastic modulus by 25%. This correlated with a small but significant increase in invasion of L. monocytogenes into murine and human syncytium. These results suggest that the syncytial actin cytoskeleton may form a general barrier against pathogen entry in humans and mice. Moreover, murine TSCs are a genetically tractable model system for the investigation of specific pathways in syncytial host defenses. PMID:24348256

  10. Action, human.

    PubMed

    Russo, M T

    2010-01-01

    The term "human action" designates the intentional and deliberate movement that is proper and exclusive to mankind. Human action is a unified structure: knowledge, intention or volition, deliberation, decision or choice of means and execution. The integration between these dimensions appears as a task that demands strength of will to achieve the synthesis of self-possession and self-control that enables full personal realisation. Recently, the debate about the dynamism of human action has been enriched by the contribution of neurosciences. Thanks to techniques of neuroimaging, neurosciences have expanded the field of investigation to the nature of volition, to the role of the brain in decision-making processes and to the notion of freedom and responsibility. PMID:20393686

  11. Classical Humanities

    ERIC Educational Resources Information Center

    Goodwin, Donn; And Others

    1975-01-01

    This article reports on a pilot course in humanities team-taught by three teachers, two from a senior high-school and one from a junior high-school, in Brookfield, Wisconsin. The specific subject matter is Greek and Roman culture. The curriculum is outlined and the basic reading list is included. (CLK)

  12. [Human monkeypox].

    PubMed

    Chastel, C

    2009-03-01

    Unlike other recent viral emergences, which were in majority caused by RNA viruses, the monkeypox results from infection by a DNA virus, an orthopoxvirus closely related to both vaccine and smallpox viruses and whose two genomic variants are known. Unexpectedly isolated from captive Asiatic monkeys and first considered as an laboratory curiosity, this virus was recognised in 1970 as an human pathogen in tropical Africa. Here it was responsible for sporadic cases following intrusions (for hunting) into tropical rain forests or rare outbreak with human-to-human transmission as observed in 1996 in Democratic Republic of Congo. As monkeypox in humans is not distinguishable from smallpox (a disease globally eradicated in 1977) it was only subjected to vigilant epidemiological surveillance and not considered as a potential threat outside Africa. This point of view radically changed in 2003 when monkeypox was introduced in the USA by African wild rodents and spread to 11 different states of this country. Responsible for 82 infections in American children and adults, this outbreak led to realize the sanitary hazards resulting from international trade of exotic animals and scientific investigations increasing extensively our knowledge of this zoonosis. PMID:18394820

  13. Humanizing Calculus

    ERIC Educational Resources Information Center

    Cirillo, Michelle

    2007-01-01

    In this article, the author explores the history and the mathematics used by Newton and Leibniz in their invention of calculus. The exploration of this topic is intended to show students that mathematics is a human invention. Suggestions are made to help teachers incorporate the mathematics and the history into their own lessons. (Contains 3…

  14. Human Trafficking

    ERIC Educational Resources Information Center

    Wilson, David McKay

    2011-01-01

    The shadowy, criminal nature of human trafficking makes evaluating its nature and scope difficult. The U.S. State Department and anti-trafficking groups estimate that worldwide some 27 million people are caught in a form of forced servitude today. Public awareness of modern-day slavery is gaining momentum thanks to new abolitionist efforts. Among…

  15. Nothing Human

    ERIC Educational Resources Information Center

    Wharram, C. C.

    2014-01-01

    In this essay C. C. Wharram argues that Terence's concept of translation as a form of "contamination" anticipates recent developments in philosophy, ecology, and translation studies. Placing these divergent fields of inquiry into dialogue enables us read Terence's well-known statement "I am a human being--I deem nothing…

  16. Effects of individually silenced N-glycosylation sites and non-synonymous single-nucleotide polymorphisms on the fusogenic function of human syncytin-2

    PubMed Central

    Cui, Lina; Wang, Huiying; Lu, Xiaoyin; Wang, Rui; Zheng, Ru; Li, Yue; Yang, Xiaokui; Jia, Wen-Tong; Zhao, Yangyu; Wang, Yongqing; Wang, Haibin; Wang, Yan-Ling; Zhu, Cheng; Lin, Hai-Yan; Wang, Hongmei

    2016-01-01

    ABSTRACT The placental syncytiotrophoblast, which is formed by the fusion of cytotrophoblast cells, is indispensable for the establishment and maintenance of normal pregnancy. The human endogenous retrovirus envelope glycoprotein syncytin-2 is the most important player in mediating trophoblast cell-cell fusion as a fusogen. We constructed expression plasmids of wild-type and 21 single-amino-acid substitution mutants of syncytin-2, including 10 N-glycosylation sites individually silenced by mutagenizing N to Q, 1 naturally occurring single-nucleotide polymorphism (SNP) N118S that introduced an N-glycosylation site, and another 10 non-synonymous SNPs located within important functional domains. We observed that syncytin-2 was highly fusogenic and that the mutants had different capacities in merging 293T cells. Of the 21 mutants, N133Q, N312Q, N443Q, C46R (in the CXXC motif) and R417H (in the heptad repeat region and immunosuppressive domain) lost their fusogenicity, whereas N332Q, N118S, T367M (in the fusion peptide), V483I (in the transmembrane domain) and T522M (in the cytoplasmic domain) enhanced the fusogenic activity. We also proved that N133, N146, N177, N220, N241, N247, N312, N332 and N443 were all glycosylated in 293T cells. A co-immunoprecipitation assay showed compromised interaction between mutants N443Q, C46R, T367M, R417H and the receptor MFSD2A, whereas N118S was associated with more receptors. We also sequenced the coding sequence of syncytin-2 in 125 severe pre-eclamptic patients and 272 normal pregnant Chinese women. Surprisingly, only 1 non-synonymous SNP T522M was found and the frequencies of heterozygous carriers were not significantly different. Taken together, our results suggest that N-glycans at residues 133, 312, 332 and 443 of syncytin-2 are required for optimal fusion induction, and that SNPs C46R, N118S, T367M, R417H, V483I and T522M can alter the fusogenic function of syncytin-2. PMID:26853155

  17. Placental endoplasmic reticulum stress negatively regulates transcription of placental growth factor via ATF4 and ATF6β: implications for the pathophysiology of human pregnancy complications

    PubMed Central

    Mizuuchi, Masahito; Cindrova‐Davies, Tereza; Olovsson, Matts; Charnock‐Jones, D Stephen; Burton, Graham J

    2016-01-01

    Abstract Low maternal circulating concentrations of placental growth factor (PlGF) are one of the hallmarks of human pregnancy complications, including fetal growth restriction (FGR) and early‐onset pre‐eclampsia (PE). Currently, PlGF is used clinically with other biomarkers to screen for high‐risk cases, although the mechanisms underlying its regulation are largely unknown. Placental endoplasmic reticulum (ER) stress has recently been found to be elevated in cases of FGR, and to an even greater extent in early‐onset PE complicated with FGR. ER stress activates the unfolded protein response (UPR); attenuation of protein translation and a reduction in cell growth and proliferation play crucial roles in the pathophysiology of these complications of pregnancy. In this study, we further identified that ER stress regulates release of PlGF. We first observed that down‐regulation of PlGF protein was associated with nuclear localization of ATF4, ATF6α and ATF6β in the syncytiotrophoblast of placentae from PE patients. Transcript analysis showed a decrease of PlGF mRNA, and an increase from genes encoding those UPR transcription factors in placentae from cases of early‐onset PE, but not of late‐onset (>34 weeks) PE, compared to term controls. Further investigations indicated a strong correlation between ATF4 and PlGF mRNA levels only (r = − 0.73, p < 0.05). These results could be recapitulated in trophoblast‐like cells exposed to chemical inducers of ER stress or hypoxia–reoxygenation. The stability of PlGF transcripts was unchanged. The use of small interfering RNA specific for transcription factors in the UPR pathways revealed that ATF4 and ATF6β, but not ATF6α, modulate PlGF transcription. To conclude, ATF4 and ATF6β act synergistically in the negative regulation of PlGF mRNA expression, resulting in reduced PlGF secretion by the trophoblast in response to stress. Therefore, these results further support the targeting of placental ER stress as a

  18. Use of a 24-kilodalton Trypanosoma cruzi recombinant protein to monitor cure of human Chagas' disease.

    PubMed Central

    Krautz, G M; Galvão, L M; Cançado, J R; Guevara-Espinoza, A; Ouaissi, A; Krettli, A U

    1995-01-01

    A 24-kDa recombinant protein from Trypanosoma cruzi (rTc24) was evaluated by enzyme-linked immunosorbent assay (ELISA) and Western blot (immunoblot) tests to identify treated chagasic patients considered parasitologically cured on the basis of persistently negative tests of hemocultures and lytic antibodies. Some of these patients were termed dissociated because their sera, although negative by the complement-mediated lysis test, were positive by conventional serology. The negative lysis test indicates the absence of active infection after specific treatment, but this assay requires live and infectious parasites and cannot be used easily in a laboratory routine. Here we tested rTc24 by ELISA and Western blotting as an alternative for the complement-mediated lysis test. For the group of patients with active infection despite the treatment (uncured patients), all the sera tested recognized rTc24 in both tests. For the dissociated patients, approximately 80% of the sera did not react with rTc24 in the ELISA or in Western blots, in agreement with the negative complement-mediated lysis tests. Thus, the 24-kDa T. cruzi recombinant antigen, when used for initial trials to evaluate cure of chagasic patients submitted to specific treatment, will allow the identification of most, but not all, cases. PMID:7559953

  19. Human Rights in the Humanities

    ERIC Educational Resources Information Center

    Harpham, Geoffrey

    2012-01-01

    Human rights are rapidly entering the academic curriculum, with programs appearing all over the country--including at Duke, Harvard, Northeastern, and Stanford Universities; the Massachusetts Institute of Technology; the Universities of Chicago, of Connecticut, of California at Berkeley, and of Minnesota; and Trinity College. Most of these…

  20. Human Protothecosis

    PubMed Central

    Lass-Flörl, Cornelia; Mayr, Astrid

    2007-01-01

    Human protothecosis is a rare infection caused by members of the genus Prototheca. Prototheca species are generally considered to be achlorophyllic algae and are ubiquitous in nature. The occurrence of protothecosis can be local or disseminated and acute or chronic, with the latter being more common. Diseases have been classified as (i) cutaneous lesions, (ii) olecranon bursitis, or (iii) disseminated or systemic manifestations. Infections can occur in both immunocompetent and immunosuppressed patients, although more severe and disseminated infections tend to occur in immunocompromised individuals. Prototheca wickerhamii and Prototheca zopfii have been associated with human disease. Usually, treatment involves medical and surgical approaches; treatment failure is not uncommon. Antifungals such as ketoconazole, itraconazole, fluconazole, and amphotericin B are the most commonly used drugs to date. Among them, amphotericin B displays the best activity against Prototheca spp. Diagnosis is largely made upon detection of characteristic structures observed on histopathologic examination of tissue. PMID:17428884

  1. Human genetics

    SciTech Connect

    Carlson, E.A.

    1984-01-01

    This text provides full and balanced coverage of the concepts requisite for a thorough understanding of human genetics. Applications to both the individual and society are integrated throughout the lively and personal narrative, and the essential principles of heredity are clearly presented to prepare students for informed participation in public controversies. High-interest, controversial topics, including recombinant DNA technology, oncogenes, embryo transfer, environmental mutagens and carcinogens, IQ testing, and eugenics encourage understanding of important social issues.

  2. Human evolution.

    PubMed

    Wood, B

    1996-12-01

    The common ancestor of modern humans and the great apes is estimated to have lived between 5 and 8 Myrs ago, but the earliest evidence in the human, or hominid, fossil record is Ardipithecus ramidus, from a 4.5 Myr Ethiopian site. This genus was succeeded by Australopithecus, within which four species are presently recognised. All combine a relatively primitive postcranial skeleton, a dentition with expanded chewing teeth and a small brain. The most primitive species in our own genus, Homo habilis and Homo rudolfensis, are little advanced over the australopithecines and with hindsight their inclusion in Homo may not be appropriate. The first species to share a substantial number of features with later Homo is Homo ergaster, or 'early African Homo erectus', which appears in the fossil record around 2.0 Myr. Outside Africa, fossil hominids appear as Homo erectus-like hominids, in mainland Asia and in Indonesia close to 2 Myr ago; the earliest good evidence of 'archaic Homo' in Europe is dated at between 600-700 Kyr before the present. Anatomically modern human, or Homo sapiens, fossils are seen first in the fossil record in Africa around 150 Kyr ago. Taken together with molecular evidence on the extent of DNA variation, this suggests that the transition from 'archaic' to 'modern' Homo may have taken place in Africa. PMID:8976151

  3. Human Capital, (Human) Capabilities and Higher Education

    ERIC Educational Resources Information Center

    Le Grange, L.

    2011-01-01

    In this article I initiate a debate into the (de)merits of human capital theory and human capability theory and discuss implications of the debate for higher education. Human capital theory holds that economic growth depends on investment in education and that economic growth is the basis for improving the quality of human life. Human capable…

  4. Human Heredity: Genetic Mechanisms in Humans.

    ERIC Educational Resources Information Center

    Blank, C. E.

    1988-01-01

    Discussed are some of the uncertainties in human genetic mechanisms that are often presented as dogma in Biology textbooks. Presented is a brief historical background and illustrations involving chromosome abnormality in humans and linkage studies in humans. (CW)

  5. Human Astroviruses

    PubMed Central

    Pintó, Rosa M.; Guix, Susana

    2014-01-01

    SUMMARY Human astroviruses (HAtVs) are positive-sense single-stranded RNA viruses that were discovered in 1975. Astroviruses infecting other species, particularly mammalian and avian, were identified and classified into the genera Mamastrovirus and Avastrovirus. Through next-generation sequencing, many new astroviruses infecting different species, including humans, have been described, and the Astroviridae family shows a high diversity and zoonotic potential. Three divergent groups of HAstVs are recognized: the classic (MAstV 1), HAstV-MLB (MAstV 6), and HAstV-VA/HMO (MAstV 8 and MAstV 9) groups. Classic HAstVs contain 8 serotypes and account for 2 to 9% of all acute nonbacterial gastroenteritis in children worldwide. Infections are usually self-limiting but can also spread systemically and cause severe infections in immunocompromised patients. The other groups have also been identified in children with gastroenteritis, but extraintestinal pathologies have been suggested for them as well. Classic HAstVs may be grown in cells, allowing the study of their cell cycle, which is similar to that of caliciviruses. The continuous emergence of new astroviruses with a potential zoonotic transmission highlights the need to gain insights on their biology in order to prevent future health threats. This review focuses on the basic virology, pathogenesis, host response, epidemiology, diagnostic assays, and prevention strategies for HAstVs. PMID:25278582

  6. Human schistosomiasis

    PubMed Central

    Colley, Daniel G; Bustinduy, Amaya L; Secor, W Evan; King, Charles H

    2015-01-01

    Human schistosomiasis—or bilharzia—is a parasitic disease caused by trematode flukes of the genus Schistosoma. By conservative estimates, at least 230 million people worldwide are infected with Schistosoma spp. Adult schistosome worms colonise human blood vessels for years, successfully evading the immune system while excreting hundreds to thousands of eggs daily, which must either leave the body in excreta or become trapped in nearby tissues. Trapped eggs induce a distinct immune-mediated granulomatous response that causes local and systemic pathological effects ranging from anaemia, growth stunting, impaired cognition, and decreased physical fitness, to organ-specific effects such as severe hepatosplenism, periportal fibrosis with portal hypertension, and urogenital inflammation and scarring. At present, preventive public health measures in endemic regions consist of treatment once every 1 or 2 years with the isoquinolinone drug, praziquantel, to suppress morbidity. In some locations, elimination of transmission is now the goal; however, more sensitive diagnostics are needed in both the field and clinics, and integrated environmental and health-care management will be needed to ensure elimination. PMID:24698483

  7. Human abilities.

    PubMed

    Sternberg, R J; Kaufman, J C

    1998-01-01

    This chapter reviews recent literature, primarily from the 1990s, on human abilities. The review opens with a consideration of the question of what intelligence is, and then considers some of the major definitions of intelligence, as well as implicit theories of intelligence around the world. Next, the chapter considers cognitive approaches to intelligence, and then biological approaches. It proceeds to psychometric or traditional approaches to intelligence, and then to broad, recent approaches. The different approaches raise somewhat different questions, and hence produce somewhat different answers. They have in common, however, the attempt to understand what kinds of mechanisms lead some people to adapt to, select, and shape environments in ways that match particularly well the demands of those environments. PMID:9496630

  8. NATO Human View Architecture and Human Networks

    NASA Technical Reports Server (NTRS)

    Handley, Holly A. H.; Houston, Nancy P.

    2010-01-01

    The NATO Human View is a system architectural viewpoint that focuses on the human as part of a system. Its purpose is to capture the human requirements and to inform on how the human impacts the system design. The viewpoint contains seven static models that include different aspects of the human element, such as roles, tasks, constraints, training and metrics. It also includes a Human Dynamics component to perform simulations of the human system under design. One of the static models, termed Human Networks, focuses on the human-to-human communication patterns that occur as a result of ad hoc or deliberate team formation, especially teams distributed across space and time. Parameters of human teams that effect system performance can be captured in this model. Human centered aspects of networks, such as differences in operational tempo (sense of urgency), priorities (common goal), and team history (knowledge of the other team members), can be incorporated. The information captured in the Human Network static model can then be included in the Human Dynamics component so that the impact of distributed teams is represented in the simulation. As the NATO militaries transform to a more networked force, the Human View architecture is an important tool that can be used to make recommendations on the proper mix of technological innovations and human interactions.

  9. The Digital Humanities as a Humanities Project

    ERIC Educational Resources Information Center

    Svensson, Patrik

    2012-01-01

    This article argues that the digital humanities can be seen as a humanities project in a time of significant change in the academy. The background is a number of scholarly, educational and technical challenges, the multiple epistemic traditions linked to the digital humanities, the potential reach of the field across and outside the humanities,…

  10. Antibodies to beta 1 and beta 2 adrenoreceptors in Chagas' disease.

    PubMed Central

    Sterin-Borda, L; Perez Leiros, C; Wald, M; Cremaschi, G; Borda, E

    1988-01-01

    Evidence accumulated over the last decade concerning human and experimental models suggests that an immunopathological mechanism may be involved in the pathogenesis of chronic Chagas' disease. In this paper we demonstrate the existence of two different circulating IgG in chagasic patients which bind with myocardial beta 1 and spleen cell beta 2 adrenoceptors, acting as non-competitive inhibitors. Both chagasic IgG against beta 1 and beta 2 adrenoceptor increased intracellular levels of cAMP that could be blocked by specific beta 1 and beta 2 adrenoceptor antagonists. The specificity for beta 1 and beta 2 adrenoceptors and the independence of other tissue reactive antibodies was demonstrated by IgG absorption with turkey red blood cell (TRBC), human lymphocytes (HL) or guinea pig red blood cells (GPRBC). The F(ab')2 fraction acted similarly. This supports the specificity of beta 1 and beta 2 adrenoceptors to the chagasic IgG and the independence of the other tissue reactive antibodies, such as EVI system. The probable pathogenic role of both beta 1 and beta 2 adrenergic chagasic antibody is discussed. PMID:2853016

  11. Human oestrus

    PubMed Central

    Gangestad, Steven W; Thornhill, Randy

    2008-01-01

    For several decades, scholars of human sexuality have almost uniformly assumed that women evolutionarily lost oestrus—a phase of female sexuality occurring near ovulation and distinct from other phases of the ovarian cycle in terms of female sexual motivations and attractivity. In fact, we argue, this long-standing assumption is wrong. We review evidence that women's fertile-phase sexuality differs in a variety of ways from their sexuality during infertile phases of their cycles. In particular, when fertile in their cycles, women are particularly sexually attracted to a variety of features that likely are (or, ancestrally, were) indicators of genetic quality. As women's fertile-phase sexuality shares with other vertebrate females' fertile-phase sexuality a variety of functional and physiological features, we propose that the term oestrus appropriately applies to this phase in women. We discuss the function of women's non-fertile or extended sexuality and, based on empirical findings, suggest ways that fertile-phase sexuality in women has been shaped to partly function in the context of extra-pair mating. Men are particularly attracted to some features of fertile-phase women, but probably based on by-products of physiological changes males have been selected to detect, not because women signal their cycle-based fertility status. PMID:18252670

  12. Human Rhinoviruses

    PubMed Central

    Lamson, Daryl M.; St. George, Kirsten; Walsh, Thomas J.

    2013-01-01

    Human rhinoviruses (HRVs), first discovered in the 1950s, are responsible for more than one-half of cold-like illnesses and cost billions of dollars annually in medical visits and missed days of work. Advances in molecular methods have enhanced our understanding of the genomic structure of HRV and have led to the characterization of three genetically distinct HRV groups, designated groups A, B, and C, within the genus Enterovirus and the family Picornaviridae. HRVs are traditionally associated with upper respiratory tract infection, otitis media, and sinusitis. In recent years, the increasing implementation of PCR assays for respiratory virus detection in clinical laboratories has facilitated the recognition of HRV as a lower respiratory tract pathogen, particularly in patients with asthma, infants, elderly patients, and immunocompromised hosts. Cultured isolates of HRV remain important for studies of viral characteristics and disease pathogenesis. Indeed, whether the clinical manifestations of HRV are related directly to viral pathogenicity or secondary to the host immune response is the subject of ongoing research. There are currently no approved antiviral therapies for HRVs, and treatment remains primarily supportive. This review provides a comprehensive, up-to-date assessment of the basic virology, pathogenesis, clinical epidemiology, and laboratory features of and treatment and prevention strategies for HRVs. PMID:23297263

  13. [Human papillomaviruses].

    PubMed

    Gross, G

    2003-10-01

    Human papillomaviruses (HPV) infect exclusively the basal cells of the skin and of mucosal epithelia adjacent to the skin such as the mouth, the upper respiratory tract, the lower genital tract and the anal canal. HPV does not lead to a viremia. Basically there are three different types of HPV infection: Clinically visible lesions, subclinical HPV infections and latent HPV infections. Distinct HPV types induce morphologically and prognostically different clinical pictures. The most common HPV associated benign tumor of the skin is the common wart. Infections of the urogenitoanal tract with specific HPV-types are recognised as the most frequent sexually transmitted viral infections. So-called "high-risk" HPV-types (HPV16, 18 and others) are regarded by the world health organisation as important risk-factors for the development of genital cancer (mainly cervical cancer), anal cancer and upper respiratory tract cancer in both genders. Antiviral substances with a specific anti-HPV effect are so far unknown. Conventional therapies of benign skin warts and of mucosal warts are mainly nonspecific. They comprise tissue-destroying therapies such as electrocautery, cryotherapy and laser. In addition cytotoxic substances such as podophyllotoxin and systemic therapy with retinoids are in use. Systemically and topically administered immunotherapies represent a new approach for treatment. Both interferons and particularly the recently developed imiquimod, an interferon-alpha and cytokine-inductor lead to better results and are better tolerated then conventional therapies. HPV-specific vaccines have been developed in the last 5 years and will be used in future for prevention and treatment of benign and malignant HPV-associated tumors of the genitoanal tract in both sexes. PMID:14610898

  14. Human Factors in Human-Systems Integration

    NASA Technical Reports Server (NTRS)

    Fitts, David J.; Sandor, Aniko; Litaker, Harry L., Jr.; Tillman, Barry

    2008-01-01

    Any large organization whose mission is to design and develop systems for humans, and train humans needs a well-developed integration and process plan to deal with the challenges that arise from managing multiple subsystems. Human capabilities, skills, and needs must be considered early in the design and development process, and must be continuously considered throughout the development lifecycle. This integration of human needs within system design is typically formalized through a Human-Systems Integration (HSI) program. By having an HSI program, an institution or organization can reduce lifecycle costs and increase the efficiency, usability, and quality of its products because human needs have been considered from the beginning.

  15. Human Research Roadmap

    NASA Video Gallery

    Crew health and performance is critical to successful human exploration beyond low Earth orbit. The Human Research Program (HRP) investigates and mitigates the highest risks to human health and per...

  16. Engineered human vaccines

    SciTech Connect

    Sandhu, J.S. . Div. of Immunology and Neurobiology)

    1994-01-01

    The limitations of human vaccines in use at present and the design requirements for a new generation of human vaccines are discussed. The progress in engineering of human vaccines for bacteria, viruses, parasites, and cancer is reviewed, and the data from human studies with the engineered vaccines are discussed, especially for cancer and AIDS vaccines. The final section of the review deals with the possible future developments in the field of engineered human vaccines and the requirement for effective new human adjuvants.

  17. Human-machine interactions

    DOEpatents

    Forsythe, J. Chris; Xavier, Patrick G.; Abbott, Robert G.; Brannon, Nathan G.; Bernard, Michael L.; Speed, Ann E.

    2009-04-28

    Digital technology utilizing a cognitive model based on human naturalistic decision-making processes, including pattern recognition and episodic memory, can reduce the dependency of human-machine interactions on the abilities of a human user and can enable a machine to more closely emulate human-like responses. Such a cognitive model can enable digital technology to use cognitive capacities fundamental to human-like communication and cooperation to interact with humans.

  18. Visualizing Humans by Computer.

    ERIC Educational Resources Information Center

    Magnenat-Thalmann, Nadia

    1992-01-01

    Presents an overview of the problems and techniques involved in visualizing humans in a three-dimensional scene. Topics discussed include human shape modeling, including shape creation and deformation; human motion control, including facial animation and interaction with synthetic actors; and human rendering and clothing, including textures and…

  19. Cooperation in human teaching.

    PubMed

    Kruger, Ann Cale

    2015-01-01

    Kline's evolutionary analysis of teaching provides welcome reframing for cross-species comparisons. However, theory based on competition cannot explain the transmission of human cultural elements that were collectively created. Humans evolved in a cultural niche and teaching-learning coevolved to transmit culture. To study human cultural variation in teaching, we need a more articulated theory of this distinctively human engagement. PMID:26786392

  20. Humanism: A Christian Perspective.

    ERIC Educational Resources Information Center

    Kaasa, Harris; And Others

    As part of a four-college project to integrate the religious tradition with humanities teaching, humanism is discussed from a Christian perspective. Definitions of the terms humanism, religion, Christianity, and Christian humanism are provided. The latter is viewed as the issues surrounding the Christian approach to the dichotomy of good and evil…

  1. The Humanities: Interconnections.

    ERIC Educational Resources Information Center

    Salomone, Ronald E., Ed.

    1985-01-01

    Focusing on a wide range of interdisciplinary themes and ideas for humanities instruction, the 17 articles in this journal issue discuss the following topics: (1) literature, humanities, and the adult learner; (2) the role of the humanities in educating for a democracy; (3) humanities in the marketplace; (4) literature versus "great books" in high…

  2. Human Research Program Opportunities

    NASA Technical Reports Server (NTRS)

    Kundrot, Craig E.

    2014-01-01

    The goal of HRP is to provide human health and performance countermeasures, knowledge, technologies, and tools to enable safe, reliable, and productive human space exploration. The Human Research Program was designed to meet the needs of human space exploration, and understand and reduce the risk to crew health and performance in exploration missions.

  3. ISS Payload Human Factors

    NASA Technical Reports Server (NTRS)

    Ellenberger, Richard; Duvall, Laura; Dory, Jonathan

    2016-01-01

    The ISS Payload Human Factors Implementation Team (HFIT) is the Payload Developer's resource for Human Factors. HFIT is the interface between Payload Developers and ISS Payload Human Factors requirements in SSP 57000. ? HFIT provides recommendations on how to meet the Human Factors requirements and guidelines early in the design process. HFIT coordinates with the Payload Developer and Astronaut Office to find low cost solutions to Human Factors challenges for hardware operability issues.

  4. Cardiac-Oxidized Antigens Are Targets of Immune Recognition by Antibodies and Potential Molecular Determinants in Chagas Disease Pathogenesis

    PubMed Central

    Dhiman, Monisha; Zago, Maria Paola; Nunez, Sonia; Amoroso, Alejandro; Rementeria, Hugo; Dousset, Pierre; Burgos, Federico Nunez; Garg, Nisha Jain

    2012-01-01

    Trypanosoma cruzi elicits reactive oxygen species (ROS) of inflammatory and mitochondrial origin in infected hosts. In this study, we examined ROS-induced oxidative modifications in the heart and determined whether the resultant oxidized cardiac proteins are targets of immune response and of pathological significance in Chagas disease. Heart biopsies from chagasic mice, rats and human patients exhibited, when compared to those from normal controls, a substantial increase in protein 4-hydroxynonenal (4-HNE), malondialdehyde (MDA), carbonyl, and 3-nitrotyrosine (3-NT) adducts. To evaluate whether oxidized proteins gain antigenic properties, heart homogenates or isolated cardiomyocytes were oxidized in vitro and one- or two-dimensional gel electrophoresis (2D-GE)/Western blotting (WB) was performed to investigate the proteomic oxidative changes and recognition of oxidized proteins by sera antibodies in chagasic rodents (mice, rats) and human patients. Human cardiomyocytes exhibited LD50 sensitivity to 30 µM 4-HNE and 100 µM H2O2 at 6 h and 12 h, respectively. In vitro oxidation with 4-HNE or H2O2 resulted in a substantial increase in 4-HNE- and carbonyl-modified proteins that correlated with increased recognition of cardiac (cardiomyocytes) proteins by sera antibodies of chagasic rodents and human patients. 2D-GE/Western blotting followed by MALDI-TOF-MS/MS analysis to identify cardiac proteins that were oxidized and recognized by human chagasic sera yielded 82 unique proteins. We validated the 2D-GE results by enzyme-linked immunosorbent assay (ELISA) and WB and demonstrated that oxidation of recombinant titin enhanced its immunogenicity and recognition by sera antibodies from chagasic hosts (rats and humans). Treatment of infected rats with phenyl-α-tert-butyl nitrone (PBN, antioxidant) resulted in normalized immune detection of cardiac proteins associated with control of cardiac pathology and preservation of heart contractile function in chagasic rats. We

  5. Expression of uPAR in human trophoblast and its role in trophoblast invasion

    PubMed Central

    Liu, Shuai; Zheng, Qin; Cui, Xin-Yuan; Dai, Kui-Xing; Yang, Xue-Song; Li, Fa-Sheng; Yan, Qiu

    2015-01-01

    Placental trophoblast cells differentiate into invasive trophoblasts or syncytiotrophoblasts. Abnormal trophoblast invasion results in pregnancy-associated disease and abortion. uPAR is a cell membrane-bound glycosylated protein, involved in physiological and pathological processes. However, uPAR expression in villi during threatened abortion and its role in trophoblast differentiation are unclear. We determined that, uPAR expression in the villi was reduced in threatened abortion patients than that in normal pregnancy. uPARsiRNA inhibited the potential for trophoblast migration and invasion in explants culture and HTR8/SVneo cells. It also enhanced forskolin-induced fusion of HTR8/SVneo cells. Overall, this study provides a possible reason for abortion. PMID:26823748

  6. Boundaries of Humanities: Writing Medical Humanities

    ERIC Educational Resources Information Center

    Bolton, Gillie

    2008-01-01

    Literature and medicine is a discipline within medical humanities, which challenges medicine to reconfigure its scientific model to become interdisciplinary, and be disciplined by arts and humanities as well as science. The psychological, emotional, spiritual and physical are inextricably linked in people, inevitably entailing provisionality,…

  7. Virtual Human Project

    SciTech Connect

    Ward, RD

    2001-06-12

    This paper describes the development of a comprehensive human modeling environment, the Virtual Human, which will be used initially to model the human respiratory system for purposes of predicting pulmonary disease or injury using lung sounds. The details of the computational environment, including the development of a Virtual Human Thorax, a database for storing models, model parameters, and experimental data, and a Virtual Human web interface are outlined. Preliminary progress in developing this environment will be presented. A separate paper at the conference describes the modeling of sound generation using computational fluid dynamics and the modeling of sound propagation in the human respiratory system.

  8. Virtual Human project

    NASA Astrophysics Data System (ADS)

    Ward, Richard C.; Kruse, Kara L.; Allgood, Glenn O.; Hively, Lee M.; Fischer, K. N.; Munro, Nancy B.; Easterly, Clay E.

    2001-08-01

    This paper describes the development of a comprehensive human modeling environment, the Virtual Human, which will be used initially to model the human respiratory system for purposes of predicting pulmonary disease or injury using lung sounds. The details of the computational environment, including the development of a Virtual Human Thorax, a database for storing models, model parameters, and experimental data, and a Virtual Human web interface are outlined. Preliminary progress in developing this environment will be presented. A separate paper at the conference describes the modeling of sound generation using computational fluid dynamics and the modeling of sound propagation in the human respiratory system.

  9. Telling the Human Story.

    ERIC Educational Resources Information Center

    Richardson, Miles

    1987-01-01

    Proposes that one of the fundamental human attributes is telling stories. Explores the debate on whether Neanderthals possessed language ability. Discusses the role of the "human story" in teaching anthropology. (DH)

  10. Human bites (image)

    MedlinePlus

    Human bites present a high risk of infection. Besides the bacteria which can cause infection, there is ... the wound extends below the skin. Anytime a human bite has broken the skin, seek medical attention.

  11. Human Resource Accounting System

    ERIC Educational Resources Information Center

    Cerullo, Michael J.

    1974-01-01

    Main objectives of human resource accounting systems are to satisfy the informational demands made by investors and by operating managers. The paper's main concern is with the internal uses of a human asset system. (Author)

  12. Pathfinder: Humans in space

    NASA Technical Reports Server (NTRS)

    Anderson, John L.

    1988-01-01

    Viewgraphs are presented on the Pathfinder program. Information is given on human exploration of the solar system, technical requirements interfaces, program objectives, space suits, human performance, man-machine systems, space habitats, life support systems, and artificial gravity

  13. Whose Human Rights?

    ERIC Educational Resources Information Center

    Rendel, Margherita

    During the last 50 years, principles, institutions, and policies of human rights have been developed worldwide. This book brings together European and international conventions on human rights, the rights of women, and the users and uses of education, and places them in their wider context. It examines issues in how human rights work, the ways in…

  14. HUMAN USE INDEX (FUTURE)

    EPA Science Inventory

    Human land uses may have major impacts on ecosystems, affecting biodiversity, habitat, air and water quality. The human use index (also known as U-index) is the percentage of human land use in an area, including agriculture, urban and suburban development, and mining. Low values ...

  15. HUMAN USE INDEX

    EPA Science Inventory

    Human land uses may have major impacts on ecosystems, affecting biodiversity, habitat, air and water quality. The human use index (also known as U-index) is the percentage of human land use in an area, including agriculture, urban and suburban development, and mining. Low values ...

  16. Visible Human Project

    MedlinePlus

    ... Mobile Gallery Site Navigation Home The Visible Human Project ® Overview The Visible Human Project ® is an outgrowth of the NLM's 1986 Long- ... The long-term goal of the Visible Human Project ® is to produce a system of knowledge structures ...

  17. Human Rights Educational Resources.

    ERIC Educational Resources Information Center

    Flowers, Nancy

    1998-01-01

    Gives a variety of educational resources on human rights that include videos, resource notebooks, books, publications, and websites along with short descriptions of the materials. Provides the contact information for a list of human-rights organizations, such as the Center for Human Rights Education and the Franklin and Eleanor Roosevelt…

  18. Expanding Human Intelligence.

    ERIC Educational Resources Information Center

    Galyean, Beverly-Colleene

    1983-01-01

    The human brain is capable of mastering skills far beyond those it is now used for. Three questions about the further evolution of human intelligence are raised: What will be the next step in human intelligence? How is the next step manifesting itself? How can we prepare for those changes? (IS)

  19. Human Rights Resource Catalogue.

    ERIC Educational Resources Information Center

    Zambrano, Elias, Comp.

    This document provides information about 25 programs/brochures which focus on human rights topics. Specific topics include: (1) counselor preparation; (2) multicultural awareness; (3) abuse and neglect; (4) Acquired Immune Deficiency Syndrome; (5) self-awareness; (6) human rights awareness and human rights of students; (7) cultural diversity; (8)…

  20. Production Of Human Antibodies

    NASA Technical Reports Server (NTRS)

    Sammons, David W.; Neil, Garry A.

    1993-01-01

    Process for making human monoclonal antibodies based on combination of techniques. Antibodies made active against specific antigen. Process involves in vivo immunization of human B lymphocyte cells in mice. B cells of interest enriched in vitro before fusion. Method potentially applicable to any antigen. Does not rely on use of Epstein-Barr virus at any step. Human lymphocytes taken from any source.

  1. HUMAN EXPOSURE ACTIVITY PATTERNS

    EPA Science Inventory

    Human activity/uptake rate data are necessary to estimate potential human exposure and intake dose to environmental pollutants and to refine human exposure models. Personal exposure monitoring studies have demonstrated the critical role that activities play in explaining and pre...

  2. Some Criteria for Humanizing.

    ERIC Educational Resources Information Center

    Read, Charlotte S.

    Patterns for humanizing the information sciences include recognizing essential "humanness," taking a holistic approach to the subject field, and being aware of the epistemological nature of how people communicate and relate to others and themselves. The complete inclusion of the human factor in information theory researches can only amplify the…

  3. Esprit: A Humanities Magazine.

    ERIC Educational Resources Information Center

    Parker, Donald G.; Capella, Barry John

    In March 1984, the first issue of "Esprit," a semi-annual humanities magazine for the 56 two-year colleges in New York State, was published. The magazine seeks to confront the apparent decline of student interest in the humanities, community doubts about the relevance of the humanities, and the seeming indifference to the special truths inherent…

  4. Financing Human Capital.

    ERIC Educational Resources Information Center

    Juffras, Jason; Sawhill, Isabel V.

    This paper examines the government's role in financing human capital investments. It first examines why private investments in education, training, and other forms of human capital are likely to fall short of socially desirable levels. It then reviews past trends in public support for human resource investments. Finally, it discusses current…

  5. Has Human Evolution Stopped?

    PubMed Central

    Templeton, Alan R.

    2010-01-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences. PMID:23908778

  6. The endocrine function of human placenta: an overview.

    PubMed

    Costa, Mariana A

    2016-01-01

    During pregnancy, several tightly coordinated and regulated processes take place to enable proper fetal development and gestational success. The formation and development of the placenta is one of these critical pregnancy events. This organ plays essential roles during gestation, including fetal nourishment, support and protection, gas exchange and production of several hormones and other mediators. Placental hormones are mainly secreted by the syncytiotrophoblast, in a highly and tightly regulated way. These hormones are important for pregnancy establishment and maintenance, exerting autocrine and paracrine effects that regulate decidualization, placental development, angiogenesis, endometrial receptivity, embryo implantation, immunotolerance and fetal development. In addition, because they are released into maternal circulation, the profile of their blood levels throughout pregnancy has been the target of intense research towards finding potential robust and reliable biomarkers to predict and diagnose pregnancy-associated complications. In fact, altered levels of these hormones have been associated with some pathologies, such as chromosomal anomalies or pre-eclampsia. This review proposes to revise and update the main pregnancy-related hormones, addressing their major characteristics, molecular targets, function throughout pregnancy, regulators of their expression and their potential clinical interest. PMID:26615903

  7. Characterization of urokinase receptor expression by human placental trophoblasts.

    PubMed

    Zini, J M; Murray, S C; Graham, C H; Lala, P K; Karikó, K; Barnathan, E S; Mazar, A; Henkin, J; Cines, D B; McCrae, K R

    1992-06-01

    The processes of implantation and placentation are both dependent on the invasion and remodeling of the uterine endometrium and vasculature by trophoblasts. Because the secretion and autocrine binding of urokinase (uPA) appears to be a common mechanism used by cells to facilitate plasmin-dependent tissue invasion, we measured the production of uPA and expression of uPA receptors by trophoblasts. Prourokinase bound specifically, reversibly, and with high affinity to cultured trophoblasts, via the uPA epidermal growth factor-like domain. Trophoblasts derived from two first-trimester placentae bound more prourokinase than cells isolated from term placentae. Furthermore, in vitro differentiation of cultured cytotrophoblasts into syncytiotrophoblasts was associated with diminished expression of urokinase receptors and a parallel decrease in the cellular content of uPA receptor mRNA. Trophoblasts also secreted prourokinase and plasminogen activator inhibitors types 1 and 2 (PAI-1 and PAI-2). Although prourokinase was secreted in amounts sufficient to endogenously saturate trophoblast uPA receptors, trophoblasts secreted greater amounts of PAI-1 and PAI-2 than uPA, and no net plasminogen activator activity was detected in trophoblast conditioned medium. In contrast, plasminogen added directly to cultured trophoblasts was readily converted to plasmin. Although the invasion and remodeling of uterine tissues by trophoblasts is a complex process dependent on several proteases of varying specificity, our findings suggest that the expression and modulation of urokinase receptors on the trophoblast cell surface may play an important role in this process. PMID:1316787

  8. Human Mitochondrial Protein Database

    National Institute of Standards and Technology Data Gateway

    SRD 131 Human Mitochondrial Protein Database (Web, free access)   The Human Mitochondrial Protein Database (HMPDb) provides comprehensive data on mitochondrial and human nuclear encoded proteins involved in mitochondrial biogenesis and function. This database consolidates information from SwissProt, LocusLink, Protein Data Bank (PDB), GenBank, Genome Database (GDB), Online Mendelian Inheritance in Man (OMIM), Human Mitochondrial Genome Database (mtDB), MITOMAP, Neuromuscular Disease Center and Human 2-D PAGE Databases. This database is intended as a tool not only to aid in studying the mitochondrion but in studying the associated diseases.

  9. Humanism in emergency medicine.

    PubMed

    Rosenzweig, S

    1993-09-01

    Emergency medicine has not yet appropriated "humanism" as a term of its own. Medical humanism needs to be interpreted in a way that is consistent with the practical goals of emergency medicine. In this essay, humanism in emergency medicine is defined by identifying the dehumanizing aspects of sudden illness and exploring of ways for sustaining the humanity of emergency department patients. Excerpts from Dr Oliver Sacks' autobiographical work A Leg to Stand On give voice to the human needs created by sudden illness and its treatment. PMID:8363690

  10. Human-technology Integration

    NASA Astrophysics Data System (ADS)

    Mullen, Katharine M.

    Human-technology integration is the replacement of human parts and extension of human capabilities with engineered devices and substrates. Its result is hybrid biological-artificial systems. We discuss here four categories of products furthering human-technology integration: wearable computers, pervasive computing environments, engineered tissues and organs, and prosthetics, and introduce examples of currently realized systems in each category. We then note that realization of a completely artificial sytem via the path of human-technology integration presents the prospect of empirical confirmation of an aware artificially embodied system.

  11. Biological races in humans.

    PubMed

    Templeton, Alan R

    2013-09-01

    Races may exist in humans in a cultural sense, but biological concepts of race are needed to access their reality in a non-species-specific manner and to see if cultural categories correspond to biological categories within humans. Modern biological concepts of race can be implemented objectively with molecular genetic data through hypothesis-testing. Genetic data sets are used to see if biological races exist in humans and in our closest evolutionary relative, the chimpanzee. Using the two most commonly used biological concepts of race, chimpanzees are indeed subdivided into races but humans are not. Adaptive traits, such as skin color, have frequently been used to define races in humans, but such adaptive traits reflect the underlying environmental factor to which they are adaptive and not overall genetic differentiation, and different adaptive traits define discordant groups. There are no objective criteria for choosing one adaptive trait over another to define race. As a consequence, adaptive traits do not define races in humans. Much of the recent scientific literature on human evolution portrays human populations as separate branches on an evolutionary tree. A tree-like structure among humans has been falsified whenever tested, so this practice is scientifically indefensible. It is also socially irresponsible as these pictorial representations of human evolution have more impact on the general public than nuanced phrases in the text of a scientific paper. Humans have much genetic diversity, but the vast majority of this diversity reflects individual uniqueness and not race. PMID:23684745

  12. Biological Races in Humans

    PubMed Central

    Templeton, Alan R.

    2013-01-01

    Races may exist in humans in a cultural sense, but biological concepts of race are needed to access their reality in a non-species-specific manner and to see if cultural categories correspond to biological categories within humans. Modern biological concepts of race can be implemented objectively with molecular genetic data through hypothesis-testing. Genetic data sets are used to see if biological races exist in humans and in our closest evolutionary relative, the chimpanzee. Using the two most commonly used biological concepts of race, chimpanzees are indeed subdivided into races but humans are not. Adaptive traits, such as skin color, have frequently been used to define races in humans, but such adaptive traits reflect the underlying environmental factor to which they are adaptive and not overall genetic differentiation, and different adaptive traits define discordant groups. There are no objective criteria for choosing one adaptive trait over another to define race. As a consequence, adaptive traits do not define races in humans. Much of the recent scientific literature on human evolution portrays human populations as separate branches on an evolutionary tree. A tree-like structure among humans has been falsified whenever tested, so this practice is scientifically indefensible. It is also socially irresponsible as these pictorial representations of human evolution have more impact on the general public than nuanced phrases in the text of a scientific paper. Humans have much genetic diversity, but the vast majority of this diversity reflects individual uniqueness and not race. PMID:23684745

  13. Office for Human Research Protections

    MedlinePlus

    ... Office for Human Research Protections The Office for Human Research Protections (OHRP) provides leadership in the protection of the rights, welfare, and wellbeing of human subjects involved in ...

  14. Human research subjects as human research workers.

    PubMed

    Lynch, Holly Fernandez

    2014-01-01

    Biomedical research involving human subjects has traditionally been treated as a unique endeavor, presenting special risks and demanding special protections. But in several ways, the regulatory scheme governing human subjects research is counter-intuitively less protective than the labor and employment laws applicable to many workers. This Article relies on analogical and legal reasoning to demonstrate that this should not be the case; in a number of ways, human research subjects ought to be fundamentally recast as human research workers. Like other workers protected under worklaw, biomedical research subjects often have interests that diverge from those in positions of control but little bargaining power for change. Bearing these important similarities in mind, the question becomes whether there is any good reason to treat subjects and protected workers differently as a matter of law. With regard to unrestricted payment, eligibility for a minimum wage, compensation for injury, and rights to engage in concerted activity, the answer is no and human subjects regulations ought to be revised accordingly. PMID:25051653

  15. Integrated Environmental Modelling: human decisions, human challenges

    USGS Publications Warehouse

    Glynn, Pierre D.

    2015-01-01

    Integrated Environmental Modelling (IEM) is an invaluable tool for understanding the complex, dynamic ecosystems that house our natural resources and control our environments. Human behaviour affects the ways in which the science of IEM is assembled and used for meaningful societal applications. In particular, human biases and heuristics reflect adaptation and experiential learning to issues with frequent, sharply distinguished, feedbacks. Unfortunately, human behaviour is not adapted to the more diffusely experienced problems that IEM typically seeks to address. Twelve biases are identified that affect IEM (and science in general). These biases are supported by personal observations and by the findings of behavioural scientists. A process for critical analysis is proposed that addresses some human challenges of IEM and solicits explicit description of (1) represented processes and information, (2) unrepresented processes and information, and (3) accounting for, and cognizance of, potential human biases. Several other suggestions are also made that generally complement maintaining attitudes of watchful humility, open-mindedness, honesty and transparent accountability. These suggestions include (1) creating a new area of study in the behavioural biogeosciences, (2) using structured processes for engaging the modelling and stakeholder communities in IEM, and (3) using ‘red teams’ to increase resilience of IEM constructs and use.

  16. Human organ markets and inherent human dignity.

    PubMed

    MacKellar, Calum

    2014-01-01

    It has been suggested that human organs should be bought and sold on a regulated market as any other material property belongingto an individual. This would have the advantage of both addressing the grave shortage of organs available for transplantation and respecting the freedom of individuals to choose to do whatever they want with their body parts. The old arguments against such a market in human organs are, therefore, being brought back into question. The article examines the different arguments both in favour and against the sale of human organs. It concludes that the body and any of its elements is a full expression of the whole person. As such, they cannot have a price if the individual is to retain his or her full inherent dignity and if society is to retain and protect this very important concept. PMID:24979876

  17. Human Performance in Space

    NASA Technical Reports Server (NTRS)

    Jones, Patricia M.; Fiedler, Edna

    2010-01-01

    Human factors is a critical discipline for human spaceflight. Nearly every human factors research area is relevant to space exploration -- from the ergonomics of hand tools used by astronauts, to the displays and controls of a spacecraft cockpit or mission control workstation, to levels of automation designed into rovers on Mars, to organizational issues of communication between crew and ground. This chapter focuses more on the ways in which the space environment (especially altered gravity and the isolated and confined nature of long-duration spaceflight) affects crew performance, and thus has specific novel implications for human factors research and practice. We focus on four aspects of human performance: neurovestibular integration, motor control and musculo-skeletal effects, cognitive effects, and behavioral health. We also provide a sampler of recent human factors studies from NASA.

  18. Human reliability analysis

    SciTech Connect

    Dougherty, E.M.; Fragola, J.R.

    1988-01-01

    The authors present a treatment of human reliability analysis incorporating an introduction to probabilistic risk assessment for nuclear power generating stations. They treat the subject according to the framework established for general systems theory. Draws upon reliability analysis, psychology, human factors engineering, and statistics, integrating elements of these fields within a systems framework. Provides a history of human reliability analysis, and includes examples of the application of the systems approach.

  19. Human target acquisition performance

    NASA Astrophysics Data System (ADS)

    Teaney, Brian P.; Du Bosq, Todd W.; Reynolds, Joseph P.; Thompson, Roger; Aghera, Sameer; Moyer, Steven K.; Flug, Eric; Espinola, Richard; Hixson, Jonathan

    2012-06-01

    The battlefield has shifted from armored vehicles to armed insurgents. Target acquisition (identification, recognition, and detection) range performance involving humans as targets is vital for modern warfare. The acquisition and neutralization of armed insurgents while at the same time minimizing fratricide and civilian casualties is a mounting concern. U.S. Army RDECOM CERDEC NVESD has conducted many experiments involving human targets for infrared and reflective band sensors. The target sets include human activities, hand-held objects, uniforms & armament, and other tactically relevant targets. This paper will define a set of standard task difficulty values for identification and recognition associated with human target acquisition performance.

  20. The psychology of humanness.

    PubMed

    Haslam, Nick; Loughnan, Steve; Holland, Elise

    2013-01-01

    This chapter explores the ways in which the concept of "humanness" illuminates a wide and fascinating variety of psychological phenomena. After introducing the concept--everyday understandings of what it is to be human--we present a model of the diverse ways in which humanness can be denied to people. According to this model people may be perceived as lacking uniquely human characteristics, and thus likened to animals, or as lacking human nature, and thus likened to inanimate objects. Both of these forms of dehumanization occur with varying degrees of subtlety, from the explicit uses of derogatory animal metaphors, to stereotypes that ascribe lesser humanness or simpler minds to particular groups, to nonconscious associations between certain humans and nonhumans. After reviewing research on dehumanization through the lens of our model we examine additional topics that the psychology of humanness clarifies, notably the perception of nonhuman animals and the objectification of women. Humanness emerges as a concept that runs an integrating thread through a variety of research literatures. PMID:23947277

  1. Artificial human vision camera

    NASA Astrophysics Data System (ADS)

    Goudou, J.-F.; Maggio, S.; Fagno, M.

    2014-10-01

    In this paper we present a real-time vision system modeling the human vision system. Our purpose is to inspire from human vision bio-mechanics to improve robotic capabilities for tasks such as objects detection and tracking. This work describes first the bio-mechanical discrepancies between human vision and classic cameras and the retinal processing stage that takes place in the eye, before the optic nerve. The second part describes our implementation of these principles on a 3-camera optical, mechanical and software model of the human eyes and associated bio-inspired attention model.

  2. Robotics for Human Exploration

    NASA Technical Reports Server (NTRS)

    Fong, Terrence; Deans, Mathew; Bualat, Maria

    2013-01-01

    Robots can do a variety of work to increase the productivity of human explorers. Robots can perform tasks that are tedious, highly repetitive or long-duration. Robots can perform precursor tasks, such as reconnaissance, which help prepare for future human activity. Robots can work in support of astronauts, assisting or performing tasks in parallel. Robots can also perform "follow-up" work, completing tasks designated or started by humans. In this paper, we summarize the development and testing of robots designed to improve future human exploration of space.

  3. Developing Human Resources through Actualizing Human Potential

    ERIC Educational Resources Information Center

    Clarken, Rodney H.

    2012-01-01

    The key to human resource development is in actualizing individual and collective thinking, feeling and choosing potentials related to our minds, hearts and wills respectively. These capacities and faculties must be balanced and regulated according to the standards of truth, love and justice for individual, community and institutional development,…

  4. Health and Humanity: Humanities 401 Syllabus.

    ERIC Educational Resources Information Center

    Snowden, Fraser; Taylor, Maxine

    A syllabus for the "Health and Humanities" interdisciplinary course at Northwestern State University, Louisiana, is presented. An introduction suggests that with the proliferation of technological advances in the field of health care, there is a need for reconsideration of many moral, ethical, legal, and humanistic questions. Information is…

  5. The Humanities' Value

    ERIC Educational Resources Information Center

    Harpham, Geoffrey Galt

    2009-01-01

    Why should society support the humanities when so many people are suffering from the effects of the economic crisis? What claim do the humanities, or scholarship generally, have on increasingly limited resources? Shouldn't such pursuits be considered luxuries at a time when people should be focusing on essentials? The alleviation of human…

  6. Human Pythiosis, Brazil

    PubMed Central

    Bosco, Sandra de Moraes Gimenes; Araújo, João Pessoa; Candeias, João Manuel Grisi; Fabiano de Franco, Marcello; Marques, Mariangela Esther Alencar; Mendoza, Leonel; Pires de Camargo, Rosangela; Marques, Silvio Alencar

    2005-01-01

    Pythiosis, caused by Pythium insidiosum, occurs in humans and animals and is acquired from aquatic environments that harbor the emerging pathogen. Diagnosis is difficult because clinical and histopathologic features are not pathognomonic. We report the first human case of pythiosis from Brazil, diagnosed by using culture and rDNA sequencing. PMID:15890126

  7. Human Mind Maps

    ERIC Educational Resources Information Center

    Glass, Tom

    2016-01-01

    When students generate mind maps, or concept maps, the maps are usually on paper, computer screens, or a blackboard. Human Mind Maps require few resources and little preparation. The main requirements are space where students can move around and a little creativity and imagination. Mind maps can be used for a variety of purposes, and Human Mind…

  8. Human Powered Centrifuge

    NASA Technical Reports Server (NTRS)

    Mulenburg, Gerald M. (Inventor); Vernikos, Joan (Inventor)

    1997-01-01

    A human powered centrifuge has independently established turntable angular velocity and human power input. A control system allows excess input power to be stored as electric energy in a battery or dissipated as heat through a resistors. In a mechanical embodiment, the excess power is dissipated in a friction brake.

  9. Human Sociobiology: Wilson's Fallacy.

    ERIC Educational Resources Information Center

    Lehrman, Nathaniel S.

    1981-01-01

    Presents an introduction to and a critique of E.O. Wilson's new science of sociobiology, which focuses on explaining the social behavior of species as diverse as ants, apes, and humans. Suggests that Wilson has gone beyond his data in claiming that complex human behaviors such as altruism are caused to any extent by genetic, as opposed to…

  10. Manage "Human Capital" Strategically

    ERIC Educational Resources Information Center

    Odden, Allan

    2011-01-01

    To strategically manage human capital in education means restructuring the entire human resource system so that schools not only recruit and retain smart and capable individuals, but also manage them in ways that support the strategic directions of the organization. These management practices must be aligned with a district's education improvement…

  11. Quantification of human responses

    NASA Technical Reports Server (NTRS)

    Steinlage, R. C.; Gantner, T. E.; Lim, P. Y. W.

    1992-01-01

    Human perception is a complex phenomenon which is difficult to quantify with instruments. For this reason, large panels of people are often used to elicit and aggregate subjective judgments. Print quality, taste, smell, sound quality of a stereo system, softness, and grading Olympic divers and skaters are some examples of situations where subjective measurements or judgments are paramount. We usually express what is in our mind through language as a medium but languages are limited in available choices of vocabularies, and as a result, our verbalizations are only approximate expressions of what we really have in mind. For lack of better methods to quantify subjective judgments, it is customary to set up a numerical scale such as 1, 2, 3, 4, 5 or 1, 2, 3, ..., 9, 10 for characterizing human responses and subjective judgments with no valid justification except that these scales are easy to understand and convenient to use. But these numerical scales are arbitrary simplifications of the complex human mind; the human mind is not restricted to such simple numerical variations. In fact, human responses and subjective judgments are psychophysical phenomena that are fuzzy entities and therefore difficult to handle by conventional mathematics and probability theory. The fuzzy mathematical approach provides a more realistic insight into understanding and quantifying human responses. This paper presents a method for quantifying human responses and subjective judgments without assuming a pattern of linear or numerical variation for human responses. In particular, quantification and evaluation of linguistic judgments was investigated.

  12. IMMUNOASSAY HUMAN EXPOSURE STUDIES

    EPA Science Inventory

    The Human Exposure Research Branch has developed several enzyme-linked immunosorbent assay (ELISA) methods to support human exposure assessment studies. Immunoassays to detect low levels (<10 ng/mL) of chlorpyrifos in food, track-in dirt and house dust have been applied to sam...

  13. Human Simulated Diving Experiments.

    ERIC Educational Resources Information Center

    Bruce, David S.; Speck, Dexter F.

    1979-01-01

    This report details several simulated divinq experiments on the human. These are suitable for undergraduate or graduate laboratories in human or environmental physiology. The experiment demonstrates that a diving reflex is precipitated by both facial cooling and apnea. (Author/RE)

  14. Assessment of Human Factors

    NASA Technical Reports Server (NTRS)

    Mount, Frances; Foley, Tico

    1999-01-01

    Human Factors Engineering, often referred to as Ergonomics, is a science that applies a detailed understanding of human characteristics, capabilities, and limitations to the design, evaluation, and operation of environments, tools, and systems for work and daily living. Human Factors is the investigation, design, and evaluation of equipment, techniques, procedures, facilities, and human interfaces, and encompasses all aspects of human activity from manual labor to mental processing and leisure time enjoyments. In spaceflight applications, human factors engineering seeks to: (1) ensure that a task can be accomplished, (2) maintain productivity during spaceflight, and (3) ensure the habitability of the pressurized living areas. DSO 904 served as a vehicle for the verification and elucidation of human factors principles and tools in the microgravity environment. Over six flights, twelve topics were investigated. This study documented the strengths and limitations of human operators in a complex, multifaceted, and unique environment. By focusing on the man-machine interface in space flight activities, it was determined which designs allow astronauts to be optimally productive during valuable and costly space flights. Among the most promising areas of inquiry were procedures, tools, habitat, environmental conditions, tasking, work load, flexibility, and individual control over work.

  15. Introduction to human factors

    SciTech Connect

    Winters, J.M.

    1988-03-01

    Some background is given on the field of human factors. The nature of problems with current human/computer interfaces is discussed, some costs are identified, ideal attributes of graceful system interfaces are outlined, and some reasons are indicated why it's not easy to fix the problems. (LEW)

  16. Evaluating the Humanities

    ERIC Educational Resources Information Center

    Brody, Howard

    2013-01-01

    How can one measure the value of teaching the humanities? The problem of assessment and accountability is prominent today, of course, in secondary and higher education. It is perhaps even more acute for those who teach the humanities in nontraditional settings, such as medical and other professional schools. The public assumes that academes can…

  17. Environment and the Humanities.

    ERIC Educational Resources Information Center

    Allen, Rodney F., Ed.; And Others

    As a conference report, the booklet is primarily devoted to abstracts of papers presented at a Conference on Environment and Humanities held in Tallahassee, Florida, April 25-27, 1976. Dr. Huston Smith of Syracuse University, the main speaker, addressed the issue of "Humanities and Environmental Awareness." Other topics discussed included: (1)…

  18. Teaching Human Rights Law.

    ERIC Educational Resources Information Center

    Berman, Howard R.

    1985-01-01

    The international community has developed a system of human rights law relevant to many areas of legal encounter, which American law schools have been slow to incorporate into curricula. Teaching human rights law provides an opportunity for law schools to enrich the learning process and contribute creatively to the respect for rights in society.…

  19. Neurobehavioral testing in humans.

    PubMed

    Anger, W K; Rohlman, D S; Storzbach, D

    2001-05-01

    The evaluation of the effects of chemical exposures on humans is a worldwide concern, and most chemicals have not been evaluated for neurotoxic effect. Human neurobehavioral research or clinical evaluations of populations exposed to chemicals must be carefully planned and structured. This unit describes the steps required to create such a study, select the appropriate measures, and evaluate the results. PMID:20957644

  20. Humanism within Globalization

    ERIC Educational Resources Information Center

    Weber, Jennifer E.

    2014-01-01

    The complexity of adult learning connects it to almost all other facets of human endeavor. Consequently, the future of adult education depends, to a large extent on who participates and the quality of such participation. Quality participation, when teamed with environments committed to a concern for humanity, launches opportunities for varied…

  1. Methods in human cytogenetics

    SciTech Connect

    1993-12-31

    Chapter 4, discusses the various techniques used in the study human cytogenetics. The methods are discussed in historical order, from direct methods to tissue culture techniques, prenatal studies, meiotic studies, sex chromatin techniques, banding techniques, prophase banding and replication studies. Nomenclature of human chromosomes and quantitative methods are also mentioned. 60 refs., 3 figs.

  2. Humane Education Projects Handbook.

    ERIC Educational Resources Information Center

    Junior League of Ogden, UT.

    This handbook was developed to promote interest in humane education and to encourage the adoption of humane education projects. Although specifically designed to assist Junior Leagues in developing such projects, the content should prove valuable to animal welfare organizations, zoos, aquariums, nature centers, and other project-oriented groups…

  3. HSI in Human Spaceflight

    NASA Technical Reports Server (NTRS)

    Baggerman, Susan D.

    2007-01-01

    This viewgraph document examines the scope of Human Systems Integration (HSI) at NASA, and the implementation of HSI in the human space flight programs. Two areas of interest are the Responsibilities and the lessons learned from the International Space Station and the strategy and approach for the Crew Exploration Vehicle.

  4. Human Granulocytic Anaplasmosis, Japan

    PubMed Central

    Gaowa; Wuritu; Kawamori, Fumihiko; Wu, Dongxing; Yoshikawa, Yuko; Chiya, Seizou; Fukunaga, Kazutoshi; Funato, Toyohiko; Shiojiri, Masaaki; Nakajima, Hideki; Hamauzu, Yoshiji; Takano, Ai; Kawabata, Hiroki; Ando, Shuji; Kishimoto, Toshio

    2013-01-01

    We retrospectively confirmed 2 cases of human Anaplasma phagocytophilum infection. Patient blood samples contained unique p44/msp2 for the pathogen, and antibodies bound to A. phagocytophilum antigens propagated in THP-1 rather than HL60 cells. Unless both cell lines are used for serodiagnosis of rickettsiosis-like infections, cases of human granulocytic anaplasmosis could go undetected. PMID:23460988

  5. Human Space Flight

    NASA Technical Reports Server (NTRS)

    Woolford, Barbara; Mount, Frances

    2004-01-01

    The first human space flight, in the early 1960s, was aimed primarily at determining whether humans could indeed survive and function in micro-gravity. Would eating and sleeping be possible? What mental and physical tasks could be performed? Subsequent programs increased the complexity of the tasks the crew performed. Table 1 summarizes the history of U.S. space flight, showing the projects, their dates, crew sizes, and mission durations. With over forty years of experience with human space flight, the emphasis now is on how to design space vehicles, habitats, and missions to produce the greatest returns to human knowledge. What are the roles of the humans in space flight in low earth orbit, on the moon, and in exploring Mars?

  6. Mars Human Exploration Objectives

    NASA Technical Reports Server (NTRS)

    Briggs, Geoff

    1998-01-01

    This paper reviews the objectives and other considerations of Human exploration of Mars. The objectives of human exploration of Mars are: (1) to learn how Mars is similar to, and different from, Earth; (2) to explore possible life, past and present; (3) to discover what Mars is like now from the perspective of Geoscience and geologic history; and (4) how did Mars form and how did its formation differ from Earth. Considerations of human Martian exploration involve: (1) having a capable base laboratory; (2) having long range transportation; (3) having operational autonomy of the crew, and the requirement of the crew to possess a range of new cognitive processes along with easy communications with terrestrial colleagues; and finally (4) creating the human habitat along with human factors which involve more than just survivability.

  7. Humanization of immunotoxins.

    PubMed

    Rybak, S M; Hoogenboom, H R; Meade, H M; Raus, J C; Schwartz, D; Youle, R J

    1992-04-15

    The construction and expression of a chimeric gene encoding a mouse/human antibody to the human transferrin receptor fused to the gene for angiogenin, a human homolog of pancreatic RNase, are described. F(ab')2-like antibody-enzyme fusions were prepared by linking the gene for human angiogenin to a chimeric anti-transferrin receptor heavy chain gene. The antibody-enzyme fusion gene was introduced into a transfectoma that secretes the chimeric light chain of the same antibody, and cell lines were cloned that synthesize and secrete the antibody-enzyme fusion protein of the expected size at a concentration of 1-5 ng/ml. Culture supernatants from clones secreting the fusion protein caused inhibition of growth and protein synthesis of K562 cells that express the human transferrin receptor but not toward a non-human-derived cell line that lacks this receptor. Whereas excess antibody to the same receptor did not itself inhibit protein synthesis, it was able to completely prevent the protein synthesis inhibition caused by the fusion protein. These results indicate that the cytotoxicity is due to a transferrin receptor-mediated mechanism involving the angiogenin portion of the fusion protein and demonstrate the feasibility of constructing recombinant antibody-RNase molecules capable of killing tumor cells bearing the transferrin receptor. The significance of the acquired cytotoxicity of a mouse/human chimeric antibody linked to a human protein may bear importantly in human therapeutic strategies that use mouse antibodies linked to toxins from plants or bacteria to target tumor cells. It is expected that the humanization of immunotoxins will lead to less toxicity and immunogenicity than currently available reagents. PMID:1565609

  8. Novel human astroviruses: Novel human diseases?

    PubMed

    Vu, Diem-Lan; Cordey, Samuel; Brito, Francisco; Kaiser, Laurent

    2016-09-01

    Astroviruses are small, non-enveloped, single-stranded positive RNA viruses that belong to the Astroviridae family. While classical human astroviruses (HAstV) are a well-recognized cause of acute non-bacterial diarrhea among young children worldwide, novel astroviruses, named HAstV-MLB and HAstV-VA/HMO, have been identified recently in humans by molecular assays. They are phylogenetically more related to animal astroviruses than to classical human astroviruses, thus suggesting cross-species transmission. Serological studies demonstrated a surprisingly high seroprevalence in certain populations and highlighted a high infection rate in the early years of life. Although their pathogenic role has not yet been clearly determined, novel astrovirus RNA sequences have been identified in different biological specimens of symptomatic patients, including the feces, plasma, cerebrospinal fluid, and brain biopsies. Thus, there is evidence that they could contribute not only to digestive tract infection, but also to unexpected clinical syndromes, notably encephalitis and meningitis. Severe infections affect mainly immunocompromised patients. These findings indicate that novel astroviruses should be considered in the differential diagnosis of immunocompromised patients with meningitis or encephalitis of unknown origin. PMID:27434149

  9. Archaea on human skin.

    PubMed

    Probst, Alexander J; Auerbach, Anna K; Moissl-Eichinger, Christine

    2013-01-01

    The recent era of exploring the human microbiome has provided valuable information on microbial inhabitants, beneficials and pathogens. Screening efforts based on DNA sequencing identified thousands of bacterial lineages associated with human skin but provided only incomplete and crude information on Archaea. Here, we report for the first time the quantification and visualization of Archaea from human skin. Based on 16 S rRNA gene copies Archaea comprised up to 4.2% of the prokaryotic skin microbiome. Most of the gene signatures analyzed belonged to the Thaumarchaeota, a group of Archaea we also found in hospitals and clean room facilities. The metabolic potential for ammonia oxidation of the skin-associated Archaea was supported by the successful detection of thaumarchaeal amoA genes in human skin samples. However, the activity and possible interaction with human epithelial cells of these associated Archaea remains an open question. Nevertheless, in this study we provide evidence that Archaea are part of the human skin microbiome and discuss their potential for ammonia turnover on human skin. PMID:23776475

  10. Human Space Exploration

    NASA Technical Reports Server (NTRS)

    Jeevarajan, Antony

    2014-01-01

    The Mars probe, launched by India a few months ago, is on its way to Mars. At this juncture, it is appropriate to talk about the opportunities presented to us for the Human Exploration of Mars. I am planning to highlight some of the challenges to take humans to Mars, descend, land, stay, ascend and return home safely. The logistics of carrying the necessary accessories to stay at Mars will be delivered in multiple stages using robotic missions. The primary ingredients for human survival is air, water, food and shelter and the necessity to recycle the primary ingredients will be articulated. Humans have to travel beyond the van Allen radiation belt under microgravity condition during this inter-planetary travel for about 6 months minimum one way. The deconditioning of human system under microgravity conditions and protection of humans from Galactic cosmic radiation during the travel should be taken into consideration. The multi-disciplinary effort to keep the humans safe and functional during this journey will be addressed.