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1.
Nat Commun ; 14(1): 3895, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37393275

RESUMO

One of the core questions of quantum physics is how to reconcile the unitary evolution of quantum states, which is information-preserving and time-reversible, with evolution following the second law of thermodynamics, which, in general, is neither. The resolution to this paradox is to recognize that global unitary evolution of a multi-partite quantum state causes the state of local subsystems to evolve towards maximum-entropy states. In this work, we experimentally demonstrate this effect in linear quantum optics by simultaneously showing the convergence of local quantum states to a generalized Gibbs ensemble constituting a maximum-entropy state under precisely controlled conditions, while introducing an efficient certification method to demonstrate that the state retains global purity. Our quantum states are manipulated by a programmable integrated quantum photonic processor, which simulates arbitrary non-interacting Hamiltonians, demonstrating the universality of this phenomenon. Our results show the potential of photonic devices for quantum simulations involving non-Gaussian states.


Assuntos
Fótons , Física , Termodinâmica , Entropia , Simulação por Computador
2.
Aust Dent J ; 67 Suppl 1: S24-S30, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35505612

RESUMO

BACKGROUND: General dental practitioners often perceive root canal treatments as complex, and specialist referrals are commonplace in general dental practice. Therefore, the aim of this study was to better understand the knowledge of Australian general dentists and their attitudes regarding endodontics in general, and specifically (RCT), to highlight barriers and facilitating factors in the provision of endodontic care. METHODS: A combined paper-based and online survey was sent to general dental practitioners. The questionnaire consisted of 27 items, presented as checkboxes and in Likert scale format. Responses were tabled and statistically contrasted using Chi-square tests and linear regression analysis. RESULTS: A significant proportion of surveyed dentists were not confident in their ability to provide endodontic care, specifically root canal treatments (RCT). Confidence depended on factors, such as time in practice, participation in continuing professional development as well as fear of litigation and type of treatment. Other factors such as the availability of appropriate instruments and referral options, had comparatively little impact on practitioner confidence. DISCUSSION: While almost all general dental practitioners (GDPs) surveyed in this study believe RCT is important for improving the long-term retention of a tooth, just over half of the GDPs say they feel confident in their knowledge and provision of root canal treatment procedures.


Assuntos
Endodontia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Atitude do Pessoal de Saúde , Austrália , Odontologia Geral , Tratamento do Canal Radicular , Encaminhamento e Consulta , Inquéritos e Questionários , Odontólogos , Padrões de Prática Odontológica
3.
Opt Express ; 28(6): 8646-8657, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32225485

RESUMO

Electro-optic modulators within Mach-Zehnder interferometers are a common construction for optical switches in integrated photonics. A challenge faced when operating at high switching speeds is that noise from the electronic drive signals will effect switching performance. Inspired by the Mach-Zehnder lattice switching devices of Van Campenhout et al. [Opt. Express17(26), 23793 (2009).] and techniques from the field of Nuclear Magnetic Resonance known as composite pulses, we present switches which offer protection against drive-noise in both the on and off state of the switch for both the phase and intensity information encoded in the switched optical mode.

4.
Phys Rev Lett ; 124(1): 013605, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31976720

RESUMO

The representation of quantum states via phase-space functions constitutes an intuitive technique to characterize light. However, the reconstruction of such distributions is challenging as it demands specific types of detectors and detailed models thereof to account for their particular properties and imperfections. To overcome these obstacles, we derive and implement a measurement scheme that enables a reconstruction of phase-space distributions for arbitrary states whose functionality does not depend on the knowledge of the detectors, thus defining the notion of detector-agnostic phase-space distributions. Our theory presents a generalization of well-known phase-space quasiprobability distributions, such as the Wigner function. We implement our measurement protocol, using state-of-the-art transition-edge sensors without performing a detector characterization. Based on our approach, we reveal the characteristic features of heralded single- and two-photon states in phase space and certify their nonclassicality with high statistical significance.

5.
Hum Reprod ; 34(12): 2456-2466, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31825483

RESUMO

STUDY QUESTION: Are uterine natural killer (uNK) cell numbers and their distribution relative to endometrial arterioles altered in women with recurrent implantation failure (RIF) compared to women with embryo implantation success (IS)? SUMMARY ANSWER: uNK cell numbers and their distribution relative to endometrial arterioles are not significantly different in women with RIF compared to women in whom embryo implantation occurs successfully following IVF. WHAT IS ALREADY KNOWN: uNK cells are regulators of decidual angiogenesis and spiral arteriole remodelling during early pregnancy. Although some studies have shown that uNK cell numbers may be altered in women with RIF, the methods used to measure uNK cell numbers have proven inconsistent, making reproduction of these results difficult. It is unclear, therefore, whether the results reported so far are reproducible. Moreover, it is not known how uNK cell numbers may impact IVF outcomes. Despite the lack of conclusive evidence, uNK cell numbers are often evaluated as a prognostic criterion in women undergoing assisted reproductive procedures. STUDY DESIGN, SIZE, DURATION: Endometrial pipelle biopsies were collected 6-8 days post-LH surge in natural cycles from women with RIF (n = 14), women with IS (n = 11) and women with potential RIF at the time of the study (PRIF; n = 9) from 2013 to 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS: uNK cells (i.e. CD56+ and/or CD16+ phenotypes) and their distribution relative to endometrial arterioles were investigated by standard immunohistochemistry protocols and quantified using Aperio ScanScopeXT images digitized by ImageJ and deconvoluted into binary images for single cell quantification using a Gaussian Blur and Yen algorithm. MAIN RESULTS AND THE ROLE OF CHANCE: There was no significant difference in the cell density of CD56+ or CD16+ uNK cells in women with RIF compared to women with IS or PRIF. There was a higher proportion of uNK cells in the distal regions compared to the regions closest to the arterioles in all patient groups. Further, we identified a significant reduction in uNK cell density in women who had a previous pregnancy compared to those who had not, regardless of their current implantation status. LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: Spiral arterioles could not always be accurately identified by digital image analysis; therefore, all endometrial arterioles were selected and analysed. Patient numbers for the study were low. However, as the clinical phenotypes of each patient were well defined, and endometrial dating was accurately determined by three independent pathologists, differences between patient groups with respect to the uNK numbers and distribution should have been measurable if uNK cell counts were to be useful as a prognostic marker of RIF. WIDER IMPLICATIONS OF THE FINDINGS: Our findings demonstrate that CD56+ and CD16+ uNK cell numbers are not significantly different in women with RIF in a typical cohort of women undergoing IVF. Further, prior pregnancy was associated with a significantly reduced number of uNK cells in both the RIF and IS patient groups, suggestive of a long-term pregnancy induced suppression of uNK cells. Combined, these findings do not support the clinical value of using uNK cell numbers as a prognostic indicator of implantation success with IVF treatment. STUDY FUNDING/COMPETING INTEREST(S): Funding for this work was provided by Royal Women's Hospital Foundation. P.P. was supported by an NHMRC Early Career Fellowship [TF 11/14] and W.T.T. was supported by an NHMRC Postgraduate Scholarship [1055814]. The authors do not have any competing interests with this study.


Assuntos
Implantação do Embrião/imunologia , Endométrio/imunologia , Infertilidade Feminina/imunologia , Células Matadoras Naturais , Adulto , Arteríolas/imunologia , Endométrio/irrigação sanguínea , Feminino , Humanos , Gravidez
6.
Reproduction ; 158(5): 389-397, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31454786

RESUMO

Uterine spiral arteries undergo remodelling in normal pregnancy, with replacement of the musculoelastic arterial media by fibrinoid containing extravillous trophoblast cells. Deficient spiral artery remodelling is associated with several adverse pregnancy outcomes. Although there are distinct components of spiral artery remodelling, assessment is subjective and often based on an overall impression of morphology. We aimed to develop a quantitative approach for assessment of uterine spiral artery remodelling. Placental bed biopsies were immunostained using smooth muscle markers, digital images of spiral arteries were captured and Adobe Photoshop was used to analyse positive immunostaining. The method was then used to investigate variation in the same vessel at different levels within a paraffin block, and the effect of parity, pre-eclampsia or miscarriage on vascular smooth muscle cell content. Results were also compared with a more subjective morphology-based assessment system. There was good intra- and interobserver agreement and the method correlated well with the more subjective assessment system. There was an overall reduction in vascular smooth muscle, as detected by caldesmon 1 (h-caldesmon) immunopositivity, with increasing gestational age from 8 weeks to term. A previous pregnancy did not affect the amount of spiral artery smooth muscle. Comparison of pre-eclampsia and late miscarriage samples with controls of the appropriate gestational age demonstrated increased medial smooth muscle in pathological samples. This technique provides a simple, rapid, reproducible and inexpensive approach to quantitative assessment of spiral artery remodelling in normal and pathological human pregnancy, a process which although fundamental for successful pregnancy, is still incompletely understood.


Assuntos
Artérias/fisiologia , Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Placenta/irrigação sanguínea , Útero/irrigação sanguínea , Remodelação Vascular/fisiologia , Aborto Espontâneo/diagnóstico , Aborto Espontâneo/patologia , Aborto Espontâneo/fisiopatologia , Anatomia Transversal/métodos , Artérias/diagnóstico por imagem , Artérias/patologia , Feminino , Humanos , Músculo Liso Vascular/diagnóstico por imagem , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Neovascularização Fisiológica/fisiologia , Placenta/diagnóstico por imagem , Placenta/patologia , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/patologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Software , Útero/diagnóstico por imagem , Útero/patologia
7.
Hum Reprod ; 34(8): 1428-1438, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31348822

RESUMO

STUDY QUESTION: Is vascular smooth muscle cell (VSMC) dedifferentiation a feature of uterine spiral artery (SpA) remodelling in early human pregnancy? SUMMARY ANSWER: Remodelling of human uterine SpAs is associated with dedifferentiation of VSMCs and can be induced in vitro by uterine natural killer (uNK) cells and extravillous trophoblast cells (EVTs). WHAT IS KNOWN ALREADY: Uterine SpAs undergo profound morphological changes in normal pregnancy with replacement of the musculoelastic arterial wall structure by fibrinoid containing EVTs. The fate of VSMCs in SpA remodelling is unknown; in guinea pig uterine artery VSMCs dedifferentiate, remain in the vessel wall and differentiate after parturition to restore the arterial wall. There is increasing evidence that uNK cells play a role in SpA remodelling. We hypothesized that SpA remodelling in human pregnancy is associated with VSMC dedifferentiation, initiated by uNK cell-derived growth factors. STUDY DESIGN, SIZE, DURATION: Formalin fixed, paraffin embedded placental bed biopsies were immunostained for angiogenic growth factor (AGF) receptors and markers of VSMC differentiation. An in vitro model of SpA remodelling using chorionic plate arteries (CPAs) was used to test the effect of different cell types and AGFs on VSMC differentiation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Placental bed biopsies were immunostained for vascular endothelial growth factor receptors 1-3 (VEGF-R1, VEGF-R2, VEGF-R3), transforming growth factor beta 1 receptors I and II (TGF-ßRI, TGF-ßRII), interferon gamma receptors 1 and 2 (IFN-γR1, IFN-γR2), Tie2, α-smooth muscle actin (α-SMA), H-caldesmon (H-Cal), myosin heavy chain (MyHC), osteopontin and smoothelin. Staining intensity was assessed using a modified quickscore. Expression by VSMCs of the AGF receptors was confirmed by laser capture microdissection and real-time RT-PCR of non-remodelled SpAs, after laser removal of the endothelium. As an in vitro model, VSMC differentiation was assessed in CPAs by immunohistochemistry after culture in uNK cell-conditioned medium (CM), EVT-CM, uNK cell/EVT co-culture CM, Ang-1, Ang-2, IFN-γ, VEGF-A and VEGF-C, and after blocking of both Ang-1 and Ang-2 in uNK-CM. MAIN RESULTS AND THE ROLE OF CHANCE: SpA VSMC expression of Tie-2 (P = 0.0007), VEGF-R2 (P = 0.005) and osteopontin (P = 0.0001) increased in partially remodelled SpAs compared with non-remodelled SpAs, while expression of contractile VSMC markers was reduced (α-SMA P < 0.0001, H-Cal P = 0.03, MyHC P = 0.03, smoothelin P = 0.0001). In the in vitro CPA model, supernatants from purified uNK cell (H-Cal P < 0.0001, MyHC P = 0.03, α-SMA P = 0.02, osteopontin P = 0.03), EVT (H-Cal P = 0.0006, MyHC P = 0.02, osteopontin P = 0.01) and uNK cell/EVT co-cultures (H-Cal P = 0.001, MyHC P = 0.05, osteopontin P = 0.02) at 12-14 weeks, but not 8-10 weeks, gestational age induced reduced expression of contractile VSMC markers and increased osteopontin expression. Addition of exogenous (10 ng/ml) Ang-1 (P = 0.006) or Ang-2 (P = 0.009) also reduced H-Cal expression in the CPA model. Inhibition of Ang-1 (P = 0.0004) or Ang-2 (P = 0.004) in uNK cell supernatants blocked the ability of uNK cell supernatants to reduce H-Cal expression. LIMITATIONS, REASONS FOR CAUTION: This is an in vitro study and the role of uNK cells, Ang-1 and Ang-2 in SpA remodelling in vivo has not yet been shown. WIDER IMPLICATIONS OF THE FINDINGS: VSMC dedifferentiation is a feature of early SpA remodelling and uNK cells and EVT play key roles in this process by secretion of Ang-1 and Ang-2. This is one of the first studies to suggest a direct role for Ang-1 and Ang-2 in VSMC biology. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a grant from British Biotechnology and Biosciences Research Council (BB/E016790/1). The authors have no competing interests to declare.


Assuntos
Artérias/citologia , Desdiferenciação Celular/fisiologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Útero/irrigação sanguínea , Artérias/metabolismo , Feminino , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Placenta/metabolismo , Gravidez , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Útero/metabolismo
8.
Reproduction ; 158(2): 211-221, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31163399

RESUMO

Vitamin D deficiency is prevalent in pregnant women and is associated with adverse pregnancy outcomes, in particular disorders of malplacentation. The active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), is a potent regulator of innate and adaptive immunity, but its immune effects during pregnancy remain poorly understood. During early gestation, the predominant immune cells in maternal decidua are uterine natural killer cells (uNK), but the responsivity of these cells to 1,25(OH)2D3 is unknown despite high levels of 1,25(OH)2D3 in decidua. Transcriptomic responses to 1,25(OH)2D3 were characterised in paired donor uNK and peripheral natural killer cells (pNK) following cytokine (CK) stimulation. RNA-seq analyses indicated 911 genes were differentially expressed in CK-stimulated uNK versus CK-stimulated pNK in the absence of 1,25(OH)2D3, with predominant differentially expressed pathways being associated with glycolysis and transforming growth factor ß (TGFß). RNA-seq also showed that the vitamin D receptor (VDR) and its heterodimer partner retinoid X receptor were differentially expressed in CK-stimulated uNK vs CK-stimulated pNK. Further analyses confirmed increased expression of VDR mRNA and protein, as well as VDR-RXR target in CK-stimulated uNK. RNA-seq analysis showed that in CK-stimulated pNK, 1,25(OH)2D3 induced 38 and suppressed 33 transcripts, whilst in CK-stimulated uNK 1,25(OH)2D3 induced 46 and suppressed 19 genes. However, multiple comparison analysis of transcriptomic data indicated that 1,25(OH)2D3 had no significant overall effect on gene expression in either CK-stimulated pNK or uNK. These data indicate that CK-stimulated uNK are transcriptionally distinct from pNK and, despite expressing abundant VDR, neither pNK nor uNK are sensitive targets for vitamin D.


Assuntos
Calcitriol/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Transcriptoma , Células Cultivadas , Citocinas , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Células Matadoras Naturais/metabolismo , Gravidez , Receptores de Calcitriol/metabolismo , Útero/imunologia
9.
Sensors (Basel) ; 16(6)2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27338399

RESUMO

Ultraviolet (UV) studies in astronomy, cosmology, planetary studies, biological and medical applications often require precision detection of faint objects and in many cases require photon-counting detection. We present an overview of two approaches for achieving photon counting in the UV. The first approach involves UV enhancement of photon-counting silicon detectors, including electron multiplying charge-coupled devices and avalanche photodiodes. The approach used here employs molecular beam epitaxy for delta doping and superlattice doping for surface passivation and high UV quantum efficiency. Additional UV enhancements include antireflection (AR) and solar-blind UV bandpass coatings prepared by atomic layer deposition. Quantum efficiency (QE) measurements show QE > 50% in the 100-300 nm range for detectors with simple AR coatings, and QE ≅ 80% at ~206 nm has been shown when more complex AR coatings are used. The second approach is based on avalanche photodiodes in III-nitride materials with high QE and intrinsic solar blindness.

10.
Br J Cancer ; 114(6): 688-96, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26930451

RESUMO

BACKGROUND: Endometrial cancer (EC) is a hormone-driven disease, and androgen receptor (AR) expression in high-grade EC (HGEC) and metastatic EC has not yet been described. METHODS: The expression pattern and prognostic value of AR in relation to oestrogen (ERα and ERß) and progesterone (PR) receptors, and the proliferation marker Ki67 in all EC subtypes (n = 85) were compared with that of healthy and hyperplastic endometrium, using immunohistochemisty and qPCR. RESULTS: Compared with proliferative endometrium, postmenopausal endometrtial epithelium showed significantly higher expression of AR (P < 0.001) and ERα (P = 0.035), which persisted in hyperplastic epithelium and in low-grade EC (LGEC). High-grade EC showed a significant loss of AR (P < 0.0001), PR (P < 0.0001) and ERß (P < 0.035) compared with LGEC, whilst maintaining weak to moderate ERα. Unlike PR, AR expression in metastatic lesions was significantly (P = 0.039) higher than that in primary tumours. Androgen receptor expression correlated with favourable clinicopathological features and a lower proliferation index. Loss of AR, with/without the loss of PR was associated with a significantly lower disease-free survival (P < 0.0001, P < 0.0001, respectively). CONCLUSIONS: Postmenopausal endometrial epithelium acquires AR whilst preserving other steroid hormone receptors. Loss of AR, PR with retention of ERα and ERß may promote the unrestrained growth of HGEC. Androgen receptor may therefore be a clinically relevant prognostic indicator and a potential therapeutic target in EC.


Assuntos
Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Receptores Androgênicos/biossíntese , Adulto , Idoso , Estudos de Casos e Controles , Neoplasias do Endométrio/patologia , Endométrio/patologia , Epitélio/metabolismo , Epitélio/patologia , Receptor alfa de Estrogênio/biossíntese , Receptor beta de Estrogênio/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Pós-Menopausa/metabolismo , Receptores de Progesterona/biossíntese
11.
Placenta ; 36(5): 611-3, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25745823

RESUMO

Hypoxia-inducible factors (HIFs), adenosine and tissue renin-angiotensin-system (RAS) promote angiogenesis and vascularisation. We investigated the temporal expression placental adenosine A2AR receptor and HIF-1α in early pregnancy and at delivery in normotensive (NT) and pre-eclamptic (PE) women. Results were compared to our previously reported angiotensin receptor data. Expression of A2AR and HIF-1α was highest at ≤10 weeks, positively correlated through pregnancy and was higher in PE than NT at delivery. The A2AR associated with the AT4R only in early pregnancy. We suggest adenosine and RAS may interact to promote placentation with a potential adaptation to poor placental perfusion in PE.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Primeiro Trimestre da Gravidez/metabolismo , Receptor A2A de Adenosina/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , Receptores de Angiotensina/metabolismo , Sistema Renina-Angiotensina
12.
J Endocrinol ; 224(3): R107-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25663707

RESUMO

During pregnancy, immune activity is tightly regulated so that antimicrobial protection of the mother and fetus is balanced with the need for immune tolerance to prevent fetal rejection. In this setting, the maternal-fetal interface, in the form of the uterine decidua, provides a heterogeneous immune cell population with the potential to mediate diverse activities throughout pregnancy. Recent studies have suggested that vitamin D may be a key regulator of immune function during pregnancy, with the fetal-maternal interface representing a prominent target. Among its non-classical actions are potent immunomodulatory effects, including induction of antibacterial responses and modulation of T-lymphocytes to suppress inflammation and promote tolerogenesis. Thus, vitamin D may play a pivotal role in normal decidual immune function by promoting innate responses to infection, while simultaneously preventing an over-elaboration of inflammatory adaptive immunity. Research to date has focused upon the potential role of vitamin D in preventing infectious diseases such as tuberculosis, as well as possibly suppressing of autoimmune disease. Nevertheless, vitamin D may also influence facets of immune function not immediately associated with primary innate responses. This review summarises our current understanding of decidual immune function with respect to the vitamin D metabolism and signalling, and as to how this may be affected by variations in maternal vitamin D status. There has recently been much interest in vitamin D supplementation of pregnant women, but our knowledge of how this may influence the function of decidua remains limited. Further insight into the immunomodulatory actions of vitamin D during pregnancy will help shed light upon this.


Assuntos
Troca Materno-Fetal/imunologia , Gravidez/imunologia , Vitamina D/fisiologia , Animais , Decídua/imunologia , Feminino , Humanos , Sistema Imunitário/fisiologia , Macrófagos/imunologia , Placenta/imunologia , Útero/citologia , Útero/imunologia
13.
Hum Reprod Update ; 21(2): 174-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25305176

RESUMO

BACKGROUND: The endometrium is the primary target organ for the 'female' sex steroid hormone estrogen, which exerts effects in the endometrium via two main classical estrogen receptor (ER) isoforms, ERα and ERß. The main function of the endometrium, embryo implantation, appears unperturbed in ERß knockout mice, which has led researchers to disregard other potentially important functional roles that ERß may have in endometrium. This review focuses on ERß in the human endometrium and its protective role from the undesired effects of ERα. METHODS: We conducted a systematic search using PubMed and Ovid for publications between January 1996 and February 2014. All studies that examined ERß expression or function in non-pregnant endometrium or cells derived from the endometrium were considered, including human and animal studies. RESULTS: Studies of the basic function of ERß isoforms in restraining ERα-mediated cell-specific trophic/mitotic responses to estrogen in other tissues has allowed appreciation of the important potential role of ERß in the regulation of cell fate in the human endometrium. Our current understanding of ERß expression and function in endometrium is, however, incomplete. ERß is dynamically expressed in healthy premenstrual endometrium, persists in post-menopausal atrophic endometrium and may play an important role in endometrial disease. All endometrial cell types express ERß and aberrations in ERß expression have been reported in almost all benign and malignant endometrial proliferative disease. CONCLUSIONS: The collective evidence suggests that ERß has an important role in normal endometrial function and also in most, if not all, benign and malignant endometrial diseases. However, the conduct of studies of endometrial ERß expression needs to be standardized: agreement is needed regarding the most appropriate control tissue for endometrial cancer studies as well as development of standardized methods for the quantification of ERß immunohistochemical data, similar to those scoring systems employed for other hormonally regulated tissues such as breast cancer, since these data may have direct clinical implications in guiding therapy.


Assuntos
Endométrio/metabolismo , Receptor beta de Estrogênio/fisiologia , Doenças Uterinas/metabolismo , Animais , Endométrio/patologia , Endométrio/fisiologia , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Feminino , Humanos , Camundongos Knockout , Modelos Biológicos , Primatas/metabolismo , Primatas/fisiologia , Doenças Uterinas/patologia
14.
Placenta ; 34 Suppl: S11-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23257209

RESUMO

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, five of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of clinical research and pregnancy disorders: 1) trophoblast deportation; 2) gestational trophoblastic disease; 3) placental insufficiency and fetal growth restriction; 4) trophoblast overinvasion and accreta-related pathologies; 5) placental thrombosis and fibrinolysis.


Assuntos
Retardo do Crescimento Fetal , Fibrinólise/fisiologia , Doença Trofoblástica Gestacional/etiologia , Insuficiência Placentária , Placentação/fisiologia , Trofoblastos/fisiologia , Feminino , Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/fisiopatologia , Humanos , Troca Materno-Fetal/fisiologia , Insuficiência Placentária/etiologia , Insuficiência Placentária/fisiopatologia , Gravidez , Trombose/etiologia , Trombose/patologia , Trofoblastos/patologia
15.
Placenta ; 33(12): 998-1004, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23040667

RESUMO

OBJECTIVES: Placenta creta is an increasingly prevalent cause of maternal morbidity/mortality. Decidua is at least focally defective and extravillous trophoblast (EVT) may be abnormal. The study aims to compare differences in migratory trophoblast and spiral artery remodeling between areas with and without decidua at the placental implantation site. STUDY DESIGN: Sixteen (12 creta, 4 non-creta) caesarean hysterectomy specimens were studied immunohistochemically. Invasive EVT and multinucleate trophoblast giant cells (MTGC) were quantified; confluent EVT (>5 opposed EVTs) and spiral artery remodeling were assessed semi-quantitatively. RESULTS: In 6 cases, placenta creta was focal. Compared to placenta creta with local decidua, cases without local decidua had increased interstitial EVT cells (×200 field) (SEM 45.6 [4.9] vs. 80.5 [3.9], p < 0.0001), fewer multinucleate trophoblast giant cells (expressed as a percentage of total EVT) (0.8 [0.3] vs. 31.5 [2.2]% p < 0.0001) and EVT was more confluent (p < 0.0001). In contrast, placenta creta cases with local decidua had a greater degree of spiral artery remodeling (mean remodeling score 1.65 [0.07] vs. 1.13 [0.05], p < 0.0001) associated with increased intramural trophoblast (p = 0.0008). The only difference between placenta creta with local decidua and normal placentation cases was an increased number of interstitial EVT cells in creta cases (45.6 [4.9] vs. 24.8 [3.2], p = 0.04). CONCLUSIONS: Numbers of interstitial EVT are increased in placenta creta, more so in cases without local decidua. Despite this spiral artery modeling is reduced in placenta creta cases with no decidua. The results emphasize the crucial role of decidua in control of trophoblast invasion and spiral artery remodeling.


Assuntos
Artérias/patologia , Decídua/patologia , Miométrio/patologia , Placenta Acreta/patologia , Circulação Placentária , Placentação , Trofoblastos/patologia , Adulto , Artérias/metabolismo , Biomarcadores/metabolismo , Movimento Celular , Decídua/irrigação sanguínea , Decídua/metabolismo , Feminino , Células Gigantes/metabolismo , Células Gigantes/patologia , Humanos , Hiperplasia , Imuno-Histoquímica , Miométrio/irrigação sanguínea , Miométrio/metabolismo , Placenta Acreta/metabolismo , Gravidez , Proteínas da Gravidez/metabolismo , Trofoblastos/metabolismo
17.
Placenta ; 33 Suppl: S9-S14, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22177322

RESUMO

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2011 there were twelve themed workshops, three of which are summarized in this report. These workshops related to vascular systems and circulation in the mother, placenta and fetus, and were divided in to 1) angiogenic signaling and regulation of fetal endothelial function; 2) placental and fetal circulation and growth; 3) spiral artery remodeling.


Assuntos
Nível de Saúde , Placenta/fisiologia , Animais , Pesquisa Biomédica/tendências , Endométrio/irrigação sanguínea , Endotélio Vascular/embriologia , Endotélio Vascular/fisiologia , Feminino , Desenvolvimento Fetal , Humanos , Masculino , Neovascularização Fisiológica , Obstetrícia/tendências , Circulação Placentária , Placentação , Gravidez , Transdução de Sinais
18.
Placenta ; 33 Suppl: S15-22, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22154501

RESUMO

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialised topics. At IFPA meeting 2011 there were twelve themed workshops, five of which are summarized in this report. These workshops related to various aspects of placental biology: 1) immunology; 2) epigenetics; 3) comparative placentation; 4) trophoblast differentiation; 5) stem cells.


Assuntos
Nível de Saúde , Placenta/fisiologia , Animais , Pesquisa Biomédica/tendências , Diferenciação Celular , Epigênese Genética , Feminino , Proteínas Fetais/genética , Proteínas Fetais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Imunomodulação , Masculino , MicroRNAs/fisiologia , Fisiologia Comparada/tendências , Placenta/citologia , Placenta/imunologia , Placentação , Gravidez , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Transplante de Células-Tronco/tendências , Células-Tronco/citologia , Células-Tronco/imunologia , Trofoblastos/citologia , Trofoblastos/imunologia
19.
Placenta ; 31(7): 595-601, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20483454

RESUMO

BACKGROUND: Extravillous trophoblast cell (EVT) invasion of maternal tissues is critical for successful pregnancy. Decidual factors, including uterine natural killer (uNK) and T cell derived cytokines play a role in regulating this process. Interleukin (IL) 8 has been implicated as a regulator of EVT invasion. HYPOTHESIS: uNK cell stimulation of EVT invasion is associated with IL-8 levels. METHODS: CD8+, total decidual and CD56(+) uNK cells (8-10 and 12-14 weeks gestational age) were cultured. IL-8 mRNA and protein levels were determined. IL-8 receptors (IL-8RA and IL-8RB) were localised in first trimester placental bed biopsies. The effect of IL-8 +/- IL-8 neutralising antibodies and CD8+ T cell or uNK cell supernatants +/- IL-8 neutralising antibodies on EVT invasion was assessed. EVT secreted levels of MMP-2, MMP-9, uPA, PAI-1 and PAI-2 were assessed by substrate zymography or Western Blot. RESULTS: High levels of IL-8 protein and mRNA were detected in all samples. IL-8RA and IL-8RB were expressed by EVT. Exogenous IL-8 stimulated EVT invasion in a paracrine manner. uNK cell supernatants, but not CD8+ cell supernatants, stimulated EVT invasion. IL-8 neutralising antibody partially abrogated this uNK cell stimulated invasion. IL-8 increased levels of secreted MMP-2, but did not alter any of the other proteases or protease inhibitors tested. CONCLUSION: uNK cell stimulation of EVT invasion is partially mediated by IL-8. Unstimulated CD8+ T cells do not alter EVT invasion despite secreting similar levels of IL-8 as uNK cells.


Assuntos
Interleucina-8/fisiologia , Células Matadoras Naturais/imunologia , Gravidez/imunologia , Trofoblastos/imunologia , Trofoblastos/fisiologia , Útero/imunologia , Linfócitos T CD8-Positivos/imunologia , Movimento Celular/fisiologia , Feminino , Humanos , Interleucina-8/imunologia , Metaloproteinase 2 da Matriz/metabolismo , Primeiro Trimestre da Gravidez/imunologia , Receptores de Interleucina-8A/metabolismo , Receptores de Interleucina-8B/metabolismo
20.
Placenta ; 31(5): 448-55, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20304486

RESUMO

The placental renin-angiotensin system (RAS) is active from early pregnancy and may have a role in placentation. Angiotensin II (AngII) acts via binding to receptor types AT1R and AT2R. Recently smaller peptide members of the angiotensin family have been recognised as having biological relevance. Angiotensin (3-8) (AngIV) has a specific receptor (AT4R) and evokes hypertrophy, vasodilatation and vascular inflammatory response. The aim of this study was to characterise placental expression of AT1R, AT2R and AT4R, and to determine whether AngII and AngIV regulate extravillous trophoblast (EVT) invasion, apoptosis and proliferation. Placental samples were obtained from women undergoing elective surgical termination of pregnancy (TOP) at 8-10 weeks gestation (early TOP), 12-14 weeks gestation (mid TOP) or at delivery following normal pregnancy or with pre-eclampsia (PE). Immunohistochemistry and qRT-PCR were performed to determine placental mRNA and protein expression of AT1R, AT2R and AT4R at all gestational ages. EVT invasion following culture with AngII or AngIV was assessed in early placental tissue using Matrigel invasion assays. Invasion was assessed on day 6 of culture and placental explants were harvested for immunohistochemical analysis of apoptosis and proliferation. The results from qRT-PCR and immunohistochemistry showed placental AT1R expression which did not vary with gestation. The highest levels of expression of AT2R were found in early and mid TOP placentae compared to term pregnancy. Expression of AT4R was increased in term placentae, with a significant reduction in PE placentae. Moreover, culture with AngIV or AngII increased EVT invasion from placental explants, which showed increased trophoblast proliferation and reduced apoptosis. This study has characterised expression of AT4R and AT1R and AT2R in human placenta throughout normal pregnancy and in PE. Both AngIV and AngII may play an important role in normal pregnancy.


Assuntos
Placentação/fisiologia , Receptores de Angiotensina/metabolismo , Trofoblastos/metabolismo , Aborto Legal , Adulto , Angiotensinas/farmacologia , Biomarcadores/metabolismo , Movimento Celular/efeitos dos fármacos , Feminino , Expressão Gênica , Idade Gestacional , Humanos , NADPH Oxidases/metabolismo , Técnicas de Cultura de Órgãos , Pré-Eclâmpsia/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/metabolismo , Receptores de Angiotensina/genética , Nascimento a Termo , Trofoblastos/efeitos dos fármacos , Xantina Oxidase/metabolismo
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