364 results on '"John D. Aplin"'
Search Results
352. Expression of- a high-molecular-weight secretory glycoprotein in human endometrium switches from epithelium to interstitium after implantation
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L.J. Hallam, M.W. Seif, M.D. Bradley, John D. Aplin, and L.J. Foden
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chemistry.chemical_classification ,medicine.medical_specialty ,Obstetrics and Gynecology ,Biology ,Epithelium ,Cell biology ,medicine.anatomical_structure ,Endocrinology ,Reproductive Medicine ,chemistry ,Internal medicine ,medicine ,Human endometrium ,Glycoprotein ,Developmental Biology - Published
- 1986
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353. A monoclonal antibody to a cell surface determinant in human endometrial epithelium: Stage-specific expression in the menstrual cycle
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Mourad W. Seif and John D. Aplin
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medicine.medical_specialty ,medicine.drug_class ,media_common.quotation_subject ,Immunocytochemistry ,Fluorescent Antibody Technique ,Biology ,Endometrium ,Immunofluorescence ,Monoclonal antibody ,Epitope ,Andrology ,Epitopes ,Mice ,Pregnancy ,Internal medicine ,Follicular phase ,Animals ,Humans ,Medicine ,Ovulation ,Menstrual Cycle ,reproductive and urinary physiology ,Menstrual cycle ,media_common ,medicine.diagnostic_test ,urogenital system ,business.industry ,Decidua ,Antibodies, Monoclonal ,Obstetrics and Gynecology ,General Medicine ,Endocrinology ,medicine.anatomical_structure ,Antigens, Surface ,biology.protein ,Female ,Antibody ,business - Abstract
A monoclonal antibody (CC25) was obtained after immunization of mice with intact glandular epithelial cells from secretory phase endometrium. Here we report a preliminary immunohistologic study in the endometrium of 29 patients in different phases of the menstrual cycle and early pregnancy. In immunofluorescence, CC25 binds to a basolaterally oriented epithelial cell surface antigen that is absent during the proliferative phase and appears suddenly in both glandular and uterine surface locations soon after ovulation. In mid and late secretory phase, the level of expression diminishes slowly. The epitope is absent from glandular epithelial cells in first-trimester decidua. However, it is associated with vascular smooth muscle cells in endometrium and decidua. CC25 promises to be a useful reagent for the analysis of endometrial function during the menstrual cycle.
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- 1987
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354. Decidual extracellular matrix
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John D. Aplin, L.J. Foden, and A.K. Charlton
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Extracellular matrix ,Reproductive Medicine ,Chemistry ,Obstetrics and Gynecology ,Developmental Biology ,Cell biology - Published
- 1986
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355. Maternal recognition of pregnancy and maintenance of the corpus luteum
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John D. Aplin
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Andrology ,Pregnancy ,medicine.anatomical_structure ,Reproductive Medicine ,business.industry ,medicine ,Obstetrics and Gynecology ,medicine.disease ,business ,Corpus luteum ,Developmental Biology - Published
- 1989
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356. A systematic review of transcriptomic studies of the human endometrium reveals inconsistently reported differentially expressed genes
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Evangeline R Walker, Mollie McGrane, John D Aplin, Daniel R Brison, and Peter T Ruane
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assisted reproduction ,uterus ,molecular biology of reproduction ,women’s health ,Reproduction ,QH471-489 ,Gynecology and obstetrics ,RG1-991 - Abstract
Genome-wide analysis of gene expression has been widely applied to study the endometrium, although to our knowledge no systematic reviews have been performed. Here, we identified 74 studies that described transcriptomes from whole (unprocessed) endometrium samples and found that these fitted into three broad investigative categories: endometrium across the menstrual cycle, endometrium in pathology and endometrium during hormone treatment. Notably, key participant information such as menstrual cycle length and body mass index was often not reported. Fertility status was frequently not defined and fertility-related pathologies, such as recurrent implantation failure (RIF) and recurrent pregnancy loss, were variably defined, while hormone treatments differed between almost every study. A range of 1307–3637 reported differentially expressed genes (DEGs) were compared in four to seven studies in five sub-categories: (i) secretory vs proliferative stage endometrium, (ii) mid-secretory vs early secretory stage endometrium, (iii) mid-secretory endometrium from ovarian stimulation-treated participants vs controls, (iv) mid-secretory endometrium from RIF patients vs controls, and (v) mid-secretory eutopic endometrium from endometriosis patients vs controls. Only the first two sub-categories yielded consistently reported DEG between ≥3 studies, albeit in small numbers (
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- 2023
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357. Engraftment potential of human placenta-derived mesenchymal stem cells after in utero transplantation in rats.
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Chie-Pein Chen, Shu-Hsiang Liu, Jian-Pei Huang, John D. Aplin, Yi-Hsin Wu, Pei-Chun Chen, Cing-Siang Hu, Chun-Chuan Ko, Ming-Yi Lee, and Chia-Yu Chen
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UTERUS ,STEM cells ,PLACENTA ,BIOMARKERS ,IMMUNOREGULATION ,LABORATORY rats ,ANIMAL models in research ,IMMUNOHISTOCHEMISTRY ,TRANSPLANTATION of organs, tissues, etc. - Abstract
BACKGROUND Human placental mesenchymal stem cells (hPMCs) are thought to be multipotent, but their fate after in utero transplantation is not known. METHODS hPMCs isolated from term placenta were assessed for their phenotype markers, mutilineage capacity, and immunomodulatory properties. Their engraftment potential was analyzed in a pregnant rat model after in utero transplantation at embryonic day 17. Immunohistochemistry, tracing of labeled cells, fluorescence in situ hybridization and real-time PCR were used to assess post-transplant chimerism. RESULTS In vitro, lineage-negative, CD34-negative hPMCs differentiated into osteocytes, adipocytes, hepatocytes and endothelial cells with tube formation, and actively suppressed the rat lymphocyte proliferative response to allogeneic lymphocyte stimulation (P in utero transplantation into pregnant rats, a low level of engraftment was achieved in various fetal tissues. Engraftment occurred in more than 60% of the fetal rats. Cells persisted for at least 12 weeks after delivery and evidence was obtained to suggest differentiation into specific lineages, including hepatocytes and hematopoietic cells. However, a greater number of hPMCs migrated to the placenta than to the fetus, thus limiting the degree of cell engraftment in fetal organs. CONCLUSIONS We conclude that hPMCs are mutipotent cells that can be engrafted long-term in immunocompetent rats after in utero transplantation. [ABSTRACT FROM AUTHOR]
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- 2009
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358. Characterisation of Osteopontin in an In Vitro Model of Embryo Implantation
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Stéphane C Berneau, Peter T Ruane, Daniel R Brison, Susan J Kimber, Melissa Westwood, and John D Aplin
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Osteopontin ,embryo implantation ,endometrium ,Cytology ,QH573-671 - Abstract
At the onset of pregnancy, embryo implantation is initiated by interactions between the endometrial epithelium and the outer trophectoderm cells of the blastocyst. Osteopontin (OPN) is expressed in the endometrium and is implicated in attachment and signalling roles at the embryo−epithelium interface. We have characterised OPN in the human endometrial epithelial Ishikawa cell line using three different monoclonal antibodies, revealing at least nine distinct molecular weight forms and a novel secretory pathway localisation in the apical domain induced by cell organisation into a confluent epithelial layer. Mouse blastocysts co-cultured with Ishikawa cell layers served to model embryo apposition, attachment and initial invasion at implantation. Exogenous OPN attenuated initial, weak embryo attachment to Ishikawa cells but did not affect the attainment of stable attachment. Notably, exogenous OPN inhibited embryonic invasion of the underlying cell layer, and this corresponded with altered expression of transcription factors associated with differentiation from trophectoderm (Gata2) to invasive trophoblast giant cells (Hand1). These data demonstrate the complexity of endometrial OPN forms and suggest that OPN regulates embryonic invasion at implantation by signalling to the trophectoderm.
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- 2019
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359. Detrimental effects of ethanol and its metabolite acetaldehyde, on first trimester human placental cell turnover and function.
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Sylvia Lui, Rebecca L Jones, Nathalie J Robinson, Susan L Greenwood, John D Aplin, and Clare L Tower
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Medicine ,Science - Abstract
Fetal alcohol spectrum disorder (FASD) describes developmental issues from high maternal alcohol intake, which commonly results in fetal growth restriction and long term morbidity. We aimed to investigate the effect of alcohol and acetaldehyde, on the first trimester placenta, the period essential for normal fetal organogenesis. Normal invasion and establishment of the placenta during this time are essential for sustaining fetal viability to term. We hypothesise that alcohol (ethanol) and acetaldehyde have detrimental effects on cytotrophoblast invasion, turnover and placental function. Taurine is an important amino acid for neuronal and physiological development, and so, its uptake was assayed in cells and placental explants exposed to alcohol or acetaldehyde. First trimester villous explants and BeWo cells were treated with 0, 10, 20, 40 mM ethanol or 0, 10, 20, 40 µM acetaldehyde. The invasive capacity of SGHPL4, a first trimester extravillous cytotrophoblast cell line, was unaffected by ethanol or acetaldehyde (p>0.05; N = 6). The cells in-cycle were estimated using immunostaining for Ki67. Proliferating trophoblast cells treated with ethanol were decreased in both experiments (explants: 40% at 20 mM and 40 mM, p
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- 2014
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360. Pregnancy-specific glycoproteins bind integrin αIIbβ3 and inhibit the platelet-fibrinogen interaction.
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Daniel K Shanley, Patrick A Kiely, Kalyan Golla, Seamus Allen, Kenneth Martin, Ronan T O'Riordan, Melanie Ball, John D Aplin, Bernhard B Singer, Noel Caplice, Niamh Moran, and Tom Moore
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Medicine ,Science - Abstract
Pregnancy-specific glycoproteins (PSGs) are immunoglobulin superfamily members encoded by multigene families in rodents and primates. In human pregnancy, PSGs are secreted by the syncytiotrophoblast, a fetal tissue, and reach a concentration of up to 400 ug/ml in the maternal bloodstream at term. Human and mouse PSGs induce release of anti-inflammatory cytokines such as IL-10 and TGFβ1 from monocytes, macrophages, and other cell types, suggesting an immunoregulatory function. RGD tri-peptide motifs in the majority of human PSGs suggest that they may function like snake venom disintegrins, which bind integrins and inhibit interactions with ligands. We noted that human PSG1 has a KGD, rather than an RGD motif. The presence of a KGD in barbourin, a platelet integrin αIIbβ3 antagonist found in snake venom, suggested that PSG1 may be a selective αIIbβ3 ligand. Here we show that human PSG1 binds αIIbβ3 and inhibits the platelet - fibrinogen interaction. Unexpectedly, however, the KGD is not critical as multiple PSG1 domains independently bind and inhibit αIIbβ3 function. Human PSG9 and mouse Psg23 are also inhibitory suggesting conservation of this function across primate and rodent PSG families. Our results suggest that in species with haemochorial placentation, in which maternal blood is in direct contact with fetal trophoblast, the high expression level of PSGs reflects a requirement to antagonise abundant (3 mg/ml) fibrinogen in the maternal circulation, which may be necessary to prevent platelet aggregation and thrombosis in the prothrombotic maternal environment of pregnancy.
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- 2013
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361. Does malaria affect placental development? Evidence from in vitro models.
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Alexandra J Umbers, Danielle I Stanisic, Maria Ome, Regina Wangnapi, Sarah Hanieh, Holger W Unger, Leanne J Robinson, Elvin Lufele, Francesca Baiwog, Peter M Siba, Christopher L King, James G Beeson, Ivo Mueller, John D Aplin, Jocelyn D Glazier, and Stephen J Rogerson
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Medicine ,Science - Abstract
BACKGROUND:Malaria in early pregnancy is difficult to study but has recently been associated with fetal growth restriction (FGR). The pathogenic mechanisms underlying malarial FGR are poorly characterized, but may include impaired placental development. We used in vitro methods that model migration and invasion of placental trophoblast into the uterine wall to investigate whether soluble factors released into maternal blood in malaria infection might impair placental development. Because trophoblast invasion is enhanced by a number of hormones and chemokines, and is inhibited by pro-inflammatory cytokines, many of which are dysregulated in malaria in pregnancy, we further compared concentrations of these factors in blood between malaria-infected and uninfected pregnancies. METHODOLOGY/PRINCIPAL FINDINGS:We measured trophoblast invasion, migration and viability in response to treatment with serum or plasma from two independent cohorts of Papua New Guinean women infected with Plasmodium falciparum or Plasmodium vivax in early pregnancy. Compared to uninfected women, serum and plasma from women with P. falciparum reduced trophoblast invasion (P = .06) and migration (P = .004). P. vivax infection did not alter trophoblast migration (P = .64). The P. falciparum-specific negative effect on placental development was independent of trophoblast viability, but associated with high-density infections. Serum from P. falciparum infected women tended to have lower levels of trophoblast invasion promoting hormones and factors and higher levels of invasion-inhibitory inflammatory factors. CONCLUSION/SIGNIFICANCE:We demonstrate that in vitro models of placental development can be adapted to indirectly study the impact of malaria in early pregnancy. These infections could result in impaired trophoblast invasion with reduced transformation of maternal spiral arteries due to maternal hormonal and inflammatory disturbances, which may contribute to FGR by limiting the delivery of maternal blood to the placenta. Future prevention strategies for malaria in pregnancy should include protection in the first half of pregnancy.
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- 2013
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362. Development of novel single-stranded nucleic acid aptamers against the pro-angiogenic and metastatic enzyme heparanase (HPSE1).
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Suzanne C Simmons, Edward A McKenzie, Lynda K Harris, John D Aplin, Paul E Brenchley, Maria N Velasco-Garcia, and Sotiris Missailidis
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Medicine ,Science - Abstract
Heparanase is an enzyme involved in extracellular matrix remodelling and heparan sulphate proteoglycan catabolism. It is secreted by metastatic tumour cells, allowing them to penetrate the endothelial cell layer and basement membrane to invade target organs. The release of growth factors at the site of cleaved heparan sulphate chains further enhance the potential of the tumour by encouraging the process of angiogenesis. This leads to increased survival and further proliferation of the tumour. Aptamers are single or double stranded oligonucleotides that recognise specific small molecules, peptides, proteins, or even cells or tissues and have shown great potential over the years as diagnostic and therapeutic agents in anticancer treatment. For the first time, single stranded DNA aptamers were successfully generated against the active heterodimer form of heparanase using a modified SELEX protocol, and eluted based on increasing affinity for the target. Sandwich ELISA assays showed recognition of heparanase by the aptamers at a site distinct from that of a polyclonal HPSE1 antibody. The binding affinities of aptamer to immobilised enzyme were high (7 × 10(7) to 8 × 10(7) M(-1)) as measured by fluorescence spectroscopy. Immunohistochemistry and immunofluorescence studies demonstrated that the aptamers were able to recognise heparanase with staining comparable or in some cases superior to that of the HPSE1 antibody control. Finally, matrigel assay demonstrated that aptamers were able to inhibit heparanase. This study provides clear proof of principle concept that nucleic acid aptamers can be generated against heparanase. These reagents may serve as useful tools to explore the functional role of the enzyme and in the future development of diagnostic assays or therapeutic reagents.
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- 2012
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363. Angiogenesis in differentiated placental multipotent mesenchymal stromal cells is dependent on integrin alpha5beta1.
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Ming-Yi Lee, Jian-Pei Huang, Yi-Yung Chen, John D Aplin, Yi-Hsin Wu, Chia-Yu Chen, Pei-Chun Chen, and Chie-Pein Chen
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Medicine ,Science - Abstract
Human placental multipotent mesenchymal stromal cells (hPMSCs) can be isolated from term placenta, but their angiogenic ability and the regulatory pathways involved are not known. hPMSCs were shown to express integrins alpha(v), alpha(4), alpha(5), beta(1), beta(3), and beta(5) and could be induced to differentiate into cells expressing endothelial markers. Increases in cell surface integrins alpha(5) and beta(1), but not alpha(4), alpha(v)beta(3), or alpha(v)beta(5), accompanied endothelial differentiation. Vascular endothelial growth factor-A augmented the effect of fibronectin in enhancing adhesion and migration of differentiated hPMSC through integrin alpha(5)beta(1), but not alpha(v)beta(3) or alpha(v)beta(5). Formation of capillary-like structures in vitro from differentiated cells was inhibited by pre-treatment with function-blocking antibodies to integrins alpha(5) and beta(1). When hPMSCs were seeded onto chick chorioallantoic membranes (CAM), human von Willebrand factor-positive cells were observed to engraft in the chick endothelium. CAMs transplanted with differentiated hPMSCs had a greater number of vessels containing human cells and more incorporated cells per vessel compared to CAMs transplanted with undifferentiated hPMSCs, and overall angiogenesis was enhanced more by the differentiated cells. Function-blocking antibodies to integrins alpha(5) and beta(1) inhibited angiogenesis in the CAM assay. These results suggest that differentiated hPMSCs may contribute to blood vessel formation, and this activity depends on integrin alpha(5)beta(1).
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- 2009
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364. Angiogenesis in Differentiated Placental Multipotent Mesenchymal Stromal Cells Is Dependent on Integrin α5β1.
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Ming-Yi Lee, Jian-Pei Huang, Yi-Yung Chen, John D. Aplin, Yi-Hsin Wu, Chia-Yu Chen, Pei-Chun Chen, and Chie-Pein Chen
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NEOVASCULARIZATION , *PLACENTA , *GRAVID uterus , *CELL membranes , *INTEGRINS , *GLYCOPROTEINS , *BLOOD coagulation factors , *CYTOKINES , *GROWTH factors - Abstract
Human placental multipotent mesenchymal stromal cells (hPMSCs) can be isolated from term placenta, but their angiogenic ability and the regulatory pathways involved are not known. hPMSCs were shown to express integrins αv, α4, α5, β1, β3, and β5 and could be induced to differentiate into cells expressing endothelial markers. Increases in cell surface integrins α5 and β1, but not α4, αvβ3, or αvβ5, accompanied endothelial differentiation. Vascular endothelial growth factor-A augmented the effect of fibronectin in enhancing adhesion and migration of differentiated hPMSC through integrin α5β1, but not αvβ3 or αvβ5. Formation of capillary-like structures in vitro from differentiated cells was inhibited by pre-treatment with functionblocking antibodies to integrins α5 and β1. When hPMSCs were seeded onto chick chorioallantoic membranes (CAM), human von Willebrand factor-positive cells were observed to engraft in the chick endothelium. CAMs transplanted with differentiated hPMSCs had a greater number of vessels containing human cells and more incorporated cells per vessel compared to CAMs transplanted with undifferentiated hPMSCs, and overall angiogenesis was enhanced more by the differentiated cells. Function-blocking antibodies to integrins α5 and β1 inhibited angiogenesis in the CAM assay. These results suggest that differentiated hPMSCs may contribute to blood vessel formation, and this activity depends on integrin α5β1. [ABSTRACT FROM AUTHOR]
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- 2009
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