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1.
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.

2.
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.

3.
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
4.
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
5.
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
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.
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
8.
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.

9.
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
10.
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
11.
Placenta ; 30(1): 79-87, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19010534

RESUMO

During early human pregnancy invasion of uterine spiral arteries by extravillous trophoblast cells contributes to their remodelling characterised by loss of musculo-elastic media and replacement by fibrinoid containing trophoblast. Despite its importance for successful pregnancy, the mechanisms underlying 'transformation' of spiral arteries are not well understood. The aim of this study was to localize expression of members of the angiopoietin (Ang) family (Ang-1, Ang-2 and their receptor Tie-2) and the vascular endothelial growth factor (VEGF) family (VEGF-A, VEGF-C, VEGF-D and their receptors VEGF-R1, VEGF-R2 and VEGF-R3) in the placental bed throughout normal human pregnancy. Placental bed biopsies were obtained from women undergoing elective termination of pregnancy at 8-10, 12-14 and 16-20 weeks' gestation and elective caesarean section at term (n=6 each group). Paraffin-embedded sections were immunostained for Ang-1, Ang-2, Tie-2, VEGF-A, VEGF-C, VEGF-D, VEGF-R1, VEGF-R2 and VEGF-R3 using an avidin biotin peroxidase technique. Reactivity of endovascular, interstitial, intramural and multinucleate extravillous trophoblast populations in the placental bed was analysed semi-quantitatively. There was an increase in the level of immunostaining of intramural EVT for Tie-2 and VEGF-C with increasing gestational age. In addition, there was a reduction in Ang-1 and Ang-2 expression by multinucleate interstitial EVT and of VEGF-R1 and VEGF-R2 by endovascular EVT with increasing gestational age. At the earlier gestational ages studied, immunostaining for Ang-1, Ang-2, Tie-2, VEGF-C, VEGF-R1 and VEGF-R2 on intramural EVT was reduced compared to both mononuclear interstitial and endovascular EVT. These findings suggest that the Ang and VEGF families may play a role in the process of spiral artery remodelling in normal pregnancy.


Assuntos
Angiopoietinas/metabolismo , Neovascularização Fisiológica/fisiologia , Placenta/irrigação sanguínea , Circulação Placentária/fisiologia , Receptor TIE-2/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Artérias/metabolismo , Cesárea , Feminino , Idade Gestacional , Humanos , Técnicas Imunoenzimáticas , Placenta/anatomia & histologia , Gravidez , Trofoblastos/citologia , Trofoblastos/metabolismo , Adulto Jovem
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(5 Pt 2): 056224, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19518553

RESUMO

We discuss the emergence of a spontaneous temperature and critical current spatial modulation in current-carrying high-temperature superconducting wire. The modulation of the critical current along the wire on a scale of 3-10 mm forces a fraction of the transport current to crisscross the resistive interface between the superconducting film and normal metal stabilizer attached to it. This generates additional heat that allows such a structure to be self-sustainable. Stability and the conditions for experimental observation of this phenomenon are also discussed.

13.
Cytopathology ; 20(6): 359-66, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18557985

RESUMO

OBJECTIVE: To determine the role of cervical cytology and colposcopy in the management of endocervical neoplasia. SETTING: Colposcopy unit and cytology laboratory in a teaching hospital. SAMPLE: Group 1 included 184 smears showing endocervical glandular neoplasia from 129 patients and group 2 included 101 patients with histology showing endocervical abnormalities in a 6-year period (1993-1998). Follow-up of 6-11 years to 2004 was available. METHODS: Group 1 were identified from the cytology computer records. Group 2 were identified from histology records on the cytology database and a record of histology cases kept for audit purposes. The clinical records were examined retrospectively. RESULTS: The positive predictive value (PPV) of abnormal endocervical cells in smears was 81.1% for significant glandular/squamous [cervical glandular intraepithelial neoplasia (CGIN)/cervical intraepithelial neoplasia grade2 (CIN2 or worse)] lesions. The PPV of colposcopy was 93.5% for significant glandular/squamous lesions of the cervix. The postcolposcopy probability of a significant lesion when colposcopy was normal was 87.5%. The sensitivity of colposcopy in detecting endocervical lesions was 9.8%. The sensitivity of cervical smears in detecting a significant endocervical abnormality (CGIN or worse) was 66.3%. The false negative rate for cytology of endocervical glandular lesions was 4.0%. CONCLUSIONS: Endocervical glandular neoplasia detected on cytology is predictive of significant cervical pathology even when colposcopy is normal, which supports excisional biopsy in the primary assessment of these smears. The high concomitant squamous abnormality rate justifies the use of colposcopy to direct biopsies from the ectocervix. Cervical cytology is the only current screening method for cervical glandular abnormalities but sensitivity is poor.


Assuntos
Colo do Útero/patologia , Colposcopia/métodos , Técnicas Citológicas/métodos , Neoplasias Epiteliais e Glandulares , Neoplasias do Colo do Útero , Biópsia/métodos , Feminino , Humanos , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Epiteliais e Glandulares/patologia , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal
14.
Cytopathology ; 20(6): 380-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19207308

RESUMO

INTRODUCTION: Conventional Pap smears (CPS) have little impact on the detection of endometrial carcinoma. Although liquid-based cytology (LBC) is replacing CPS in the UK, experience with identification of endometrial cancers with this technique is limited. AIM: To compare the accuracy of the SurePath LBC with that of CPS for detection of endometrial cancers. METHODS: Our study group comprised SurePath LBC samples reported as atypical endometrial cells and endometrial adenocarcinoma (classified respectively as borderline, code 8 and ?glandular neoplasia, code 6 for the NHS Cervical Screening Programme statistics) in 2004-2005. CPS reported as atypical endometrial cells or adenocarcinoma in 1993-1998 comprised the control group. Histological follow-up was obtained. RESULTS: Endometrial abnormalities were reported in 95 (0.073%) of 130 352 LBC samples, comprising 75 (0.058%) atypical endometrial cells and 20 (0.015%) endometrial adenocarcinoma reports. Of 409 495 CPS, 117 (0.029%) were diagnosed as endometrial abnormalities, comprising 59 (0.014%) atypical endometrial cells and 58 (0.014%) endometrial adenocarcinoma reports. Thus, the endometrial adenocarcinoma reporting rate was similar in both groups, but that for atypical endometrial cells was higher with LBC (P < 0.001). The positive predictive value for endometrial cancer of endometrial adenocarcinoma and atypical endometrial cell reports in the LBC group was 73.3 and 18.8%, respectively, compared with 42.3 and 6.7% in the CPS group. The endometrial adenocarcinoma patients in CPS group were older (mean age 62.5 years versus 56.5 years) and most (22/25) were symptomatic, whereas most (13/17) patients in the LBC group were asymptomatic at the time of sampling (P < 0.001). CONCLUSION: SurePath LBC is at least as accurate a method for detecting endometrial cancer as CPS. SurePath LBC demonstrates enhanced identification of endometrial pathology in asymptomatic women in the cervical screening programme.


Assuntos
Técnicas Citológicas/métodos , Neoplasias do Endométrio/diagnóstico , Adulto , Idoso , Neoplasias do Endométrio/patologia , Feminino , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
Placenta ; 29 Suppl A: S92-4, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18037165

RESUMO

Between 11% and 20% of all clinically recognised pregnancies are lost before the 20th week of gestation, with huge financial and personal implications. Immune mechanisms have been proposed to play a role in unexplained recurrent miscarriage. Considerable attention has focused on endometrial leucocyte populations in recurrent miscarriage, although the underlying pathogenesis remains largely unexplained. The mechanisms underlying sporadic miscarriage are even less well understood, although aneuploidy is the commonest attributable cause of early (

Assuntos
Aborto Espontâneo/patologia , Mola Hidatiforme/patologia , Útero/patologia , Aborto Espontâneo/imunologia , Aborto Espontâneo/metabolismo , Educação , Feminino , Humanos , Mola Hidatiforme/imunologia , Mola Hidatiforme/metabolismo , Estresse Oxidativo , Gravidez , Útero/imunologia , Útero/metabolismo
16.
Placenta ; 28(8-9): 965-71, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17531316

RESUMO

Extravillous trophoblast invasion of uterine stroma and spiral arteries (SA) is essential for normal pregnancy and is reduced in preeclampsia and late miscarriage. The control mechanisms are not understood, but transforming growth factor-beta (TGF-beta) may be a candidate. Placental and placental bed biopsies were obtained from early (8(+0)-12(+6) weeks) euploid miscarriages (n = 10), early aneuploid miscarriages (n = 10), late (13(+0)-19(+6) weeks) euploid miscarriages (n = 10) and controls of the same gestation (n = 20). Frozen sections were immunostained for TGF-beta1, 2 and 3. Immunoreactivity of trophoblast and uterine cell populations was assessed semi-quantitatively. TGF-beta1 immunolocalization was limited to extracellular matrix in cytotrophoblast islands and cytotrophoblast shell, perivascular fibrinoid and interstitial trophoblast and did not differ in miscarriage compared with controls. TGF-beta2 was expressed additionally in endovascular trophoblast and multinucleate trophoblast giant cells. There was no aberrant TGF-beta2 immunolocalization in late miscarriage, but TGF-beta2 immunoreactivity was increased in extracellular matrix in cytotrophoblast islands in early miscarriage. TGF-beta3 was absent from all cell populations. Stromal and extravillous trophoblast TGF-beta2 immunolocalization suggests a more important role in trophoblast invasion than TGF-beta1, but neither isoform was altered in miscarriage. Altered TGF-beta localization is therefore unlikely to play a role in abnormal trophoblast invasion and SA transformation in miscarriage.


Assuntos
Aborto Espontâneo , Placenta , Aborto Espontâneo/metabolismo , Humanos , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Fator de Crescimento Transformador beta , Trofoblastos/metabolismo
17.
Placenta ; 28(5-6): 390-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16905187

RESUMO

The applicability of trophoblast-like cell lines to the study of trophoblast function has been widely debated. The present study investigated the effect of oxygen on the invasiveness, apoptosis, proliferation and secreted proteases of four different trophoblast cell lines; HTR-8/SVneo, SGHPL-4, JEG3 and JAR. All experiments were performed at 20% and 3% oxygen for 24, 48 and 72h. Immunostaining for integrins alpha1, alpha6 and beta3, cytokeratin 7 and HLA-G was used to determine the phenotype of the different cell lines. Invasion was assessed using the Matrigel invasion assay. Immunostaining for M30 and Ki67 determined levels of apoptosis and proliferation, respectively. Gelatin and casein/plasminogen zymography were performed on conditioned media to determine levels of secreted matrix metalloproteinase (MMP) 2 and MMP9 and urokinase plasminogen activator (uPA), respectively. None of the cell lines immunostained for all markers normally expressed by extravillous trophoblast cells. Invasiveness of HTR-8/SVneo and JEG3 cells cultured in 3% oxygen was increased after 24h but was inhibited by 72h in culture. Invasion of SGHPL-4 cells was inhibited after culture in 3% oxygen for 24h. Invasion by JAR cells was not affected by changes in oxygen concentration. The different cell lines also displayed different responses to culture period in 3% oxygen with respect to apoptosis, proliferation and secreted proteases. Care should be taken before results obtained using cell lines as a model for EVT are extrapolated to extravillous trophoblast cell behaviour in vivo.


Assuntos
Hipóxia Celular , Consumo de Oxigênio , Trofoblastos/fisiologia , Animais , Apoptose , Divisão Celular , Linhagem Celular , Antígenos HLA/genética , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/genética , Integrinas/genética , Queratinas/genética , Camundongos , Trofoblastos/citologia
19.
J Endocrinol ; 189(3): 465-71, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16731778

RESUMO

Thyroid hormones (THs) are essential for normal fetal development, with even mild perturbation in maternal thyroid status in early pregnancy being associated with neurodevelopmental delay in children. Transplacental transfer of maternal THs is critical, with increasing evidence suggesting a role for 3,3',5-tri-iodothyronine (T3) in development and function of the placenta itself, as well as in development of the central nervous and other organ systems. Intrauterine growth restriction (IUGR) is associated with fetal hypothyroxinaemia, a factor that may contribute to neurodevelopmental delay. The recent description of monocarboxylate transporter 8 (MCT8) as a powerful and specific TH membrane transporter, and the association of MCT8 mutations with profound neurodevelopmental delay, led us to explore MCT8 expression in placenta. We describe the expression of MCT8 in normal human placenta throughout gestation, and in normal third-trimester placenta compared with that associated with IUGR using quantitative reverse transcriptase PCR. MCT8 mRNA was detected in placenta from early first trimester, with a significant increase with advancing gestation (P=0.007). In the early third trimester, MCT8 mRNA was increased in IUGR placenta compared with normal samples matched for gestational age (P<0.05), but there was no difference between IUGR and normal placenta in the late third trimester. Western immunoblotting findings in IUGR and normal placentae were in accord with mRNA data. MCT8 immunostaining was demonstrated in villous cytotrophoblast and syncytiotrophoblast as well as extravillous trophoblast cells from the first trimester onwards with increasingly widespread immunoreactivity seen with advancing gestation. In conclusion, expression of MCT8 in placenta from early gestation is compatible with an important role in TH transport during fetal development and a specific role in placental development. Altered expression in placenta associated with IUGR may reflect a compensatory mechanism attempting to increase T3 uptake by trophoblast cells.


Assuntos
Retardo do Crescimento Fetal/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Placenta/metabolismo , Adulto , Análise de Variância , Western Blotting/métodos , Estudos de Casos e Controles , Membranas Extraembrionárias/química , Membranas Extraembrionárias/metabolismo , Feminino , Idade Gestacional , Humanos , Imuno-Histoquímica/métodos , Transportadores de Ácidos Monocarboxílicos/análise , Transportadores de Ácidos Monocarboxílicos/genética , Placenta/química , Gravidez , Terceiro Trimestre da Gravidez , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Simportadores , Hormônios Tireóideos/metabolismo , Trofoblastos/química , Trofoblastos/metabolismo
20.
Oncogene ; 20(41): 5878-87, 2001 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-11593393

RESUMO

Epithelial ovarian cancers (EOCs) arise in the Ovarian Surface Epithelium (OSE). This tissue is a simple, poorly committed mesothelium which exhibits characteristics of epithelial and mesenchymal cells when grown in culture. In contrast, EOCs frequently exhibit properties of complex epithelial tissues of the female reproductive tract, such as oviductal, endometrial and cervical epithelia, and show induction of expression of epithelial markers such as E-cadherin. Fibroblast Growth Factor Receptor 2 isoform IIIb (FGF receptor 2-IIIb) is a spliced variant of FGF receptor 2 that binds the ligands FGF-1 and FGF-7 with high affinity, and is expressed exclusively by epithelial cells. We have studied the expression of FGF receptor 2-IIIb and its ligands in primary cultures of normal human OSE, EOC cell lines and snap frozen tissue from EOCs. Expression of FGF receptor 2-IIIb mRNA is undetectable in normal OSE, but is expressed in 16/20 (80%) of EOCs. FGFs 1 and 7 mRNAs are expressed in normal OSE, whilst only 4/20 (20%) and 12/20 (60%) of EOCs demonstrated expression for these ligands respectively. However, FGF-7 protein was detected in 70% (mean level=0.7 ng/ml) of ascitic fluids obtained from patients with EOC. FGFs 1 and 7 stimulate DNA synthesis in EOC cell lines that express FGF receptor 2-IIIb. Moreover, DNA synthesis in these cell lines can be partially blocked by blocking antisera to FGFs 1 and 7. It is suggested that induction of expression of FGF receptor 2-IIIb may play a role in the development of EOCs by rendering the OSE susceptible to paracrine and/or autocrine stimulation by its requisite FGF ligands.


Assuntos
Fator 2 de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/metabolismo , Ovário/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite/metabolismo , Caderinas/metabolismo , DNA de Neoplasias/biossíntese , Feminino , Fator 1 de Crescimento de Fibroblastos , Fator 7 de Crescimento de Fibroblastos , Humanos , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Células Tumorais Cultivadas/metabolismo
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