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1.
BMC Pregnancy Childbirth ; 21(1): 38, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33419397

RESUMO

BACKGROUND: The complexity of fetal medicine (FM) referrals that can be managed within obstetric units is dependent on the availability of specialist ultrasound expertise. Telemedicine can effectively transfer real-time ultrasound images via video-conferencing. We report the successful introduction of a fetal ultrasound telemedicine service linking a specialist fetal medicine (FM) centre and a remote obstetric unit. METHODS: Over a four-year period from October 2015, all women referred for FM consultation from the obstetric unit were seen via telemedicine, excluding cases where invasive testing, intrauterine therapy or cardiac anomalies were anticipated. The outcomes measured included the indication for FM referral; scan duration and image and sound quality during the consultation. Women's perceptions of the telemedicine consultation and estimated costs to attend the FM centre were measured by a structured questionnaire completed following the first telemedicine appointment during the Phase 1 of the project. RESULTS: Overall, 297 women had a telemedicine consultation during Phase 1 (pilot and evaluation) and Phase 2 (embedding and adoption) of the project, which covered a 4 year period 34 women completed questionnaires during the Phase 1 of the study. Travel to the telemedicine consultation took a median (range) time of 20 min (4150), in comparison to an estimated journey of 230 min (120,450) to the FM centre. On average, women would have spent approximately £28 to travel to the FM centre per visit. The overall costs for the woman and her partner/ friend to attend the FM centre was estimated to be £439. Women were generally satisfied with the service and valued the opportunity to have a FM consultation locally. CONCLUSIONS: We have demonstrated that a fetal ultrasound telemedicine service can be successfully introduced to provide FM ultrasound of sufficient quality to allow fetal diagnosis and specialist consultation with parents. Furthermore, the service is acceptable to parents, has shown a reduction in family costs and journey times.


Assuntos
Gestantes/psicologia , Telemedicina/organização & administração , Ultrassonografia Pré-Natal/métodos , Adolescente , Adulto , Custos e Análise de Custo , Feminino , Financiamento Pessoal/economia , Acessibilidade aos Serviços de Saúde/economia , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Satisfação do Paciente , Gravidez , Encaminhamento e Consulta/estatística & dados numéricos , Telemedicina/economia , Telemedicina/normas , Telemedicina/estatística & dados numéricos , Fatores de Tempo , Ultrassonografia Pré-Natal/economia , Ultrassonografia Pré-Natal/normas , Ultrassonografia Pré-Natal/estatística & dados numéricos , Reino Unido , Adulto Jovem
2.
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
3.
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
4.
Diabet Med ; 36(2): 195-202, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30067873

RESUMO

AIMS: To investigate the views and experience of pregnant women newly diagnosed with gestational diabetes mellitus participating in a 1200 kcal/day diet to achieve moderate weight loss (the WELLBABE study), and to explore barriers to and facilitators of adherence. METHODS: Twelve participants engaged in semi-structured interviews after completion of the 4-week diet. An interview schedule was devised using open-ended questions guided by the Theoretical Domains Framework. Transcript responses were analysed thematically. RESULTS: Participants were anxious about their diagnosis of gestational diabetes, but concerns related to dieting in pregnancy were allayed by reassurance from the research team. Participants expected health benefits, improved knowledge and support from enrolling on the study. The participants' primary motivator to diet adherence was their baby's wellbeing. Other facilitatory factors included improving their own health and reducing any future risk of diabetes. Trying to provide reliable results and receiving extra care also facilitated adherence. Partners, friends and family were an important source of social support and no barrier caused by concern about weight loss in pregnancy was encountered. Observed and experienced physical changes and feedback from the research team positively reinforced adherence. The main barrier was that learning new skills was initially time-consuming. CONCLUSIONS: Weight loss was acceptable to women with gestational diabetes provided with clear information about likely benefit. A randomized controlled trial of this intervention is now required, employing clear information and feedback of glycaemic benefit to facilitate efficacy.


Assuntos
Atitude Frente a Saúde , Diabetes Gestacional/psicologia , Redução de Peso/fisiologia , Diabetes Gestacional/dietoterapia , Retroalimentação Psicológica , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Adesão à Medicação , Motivação , Projetos Piloto , Gravidez , Estudos Prospectivos , Reforço Psicológico , Autoeficácia , Responsabilidade Social , Apoio Social
5.
Int J Obes (Lond) ; 41(7): 1018-1026, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28216644

RESUMO

OBJECTIVES: Randomised controlled trials are required to address causality in the reported associations between maternal influences and offspring adiposity. The aim of this study was to determine whether an antenatal lifestyle intervention, associated with improvements in maternal diet and reduced gestational weight gain (GWG) in obese pregnant women leads to a reduction in infant adiposity and sustained improvements in maternal lifestyle behaviours at 6 months postpartum. SUBJECTS AND METHODS: We conducted a planned postnatal follow-up of a randomised controlled trial (UK Pregnancies Better Eating and Activity Trial (UPBEAT)) of a complex behavioural intervention targeting maternal diet (glycaemic load (GL) and saturated fat intake) and physical activity in 1555 obese pregnant women. The main outcome measure was infant adiposity, assessed by subscapular and triceps skinfold thicknesses. Maternal diet and physical activity, indices of the familial lifestyle environment, were assessed by questionnaire. RESULTS: A total of 698 (45.9%) infants (342 intervention and 356 standard antenatal care) were followed up at a mean age of 5.92 months. There was no difference in triceps skinfold thickness z-scores between the intervention vs standard care arms (difference -0.14 s.d., 95% confidence interval -0.38 to 0.10, P=0.246), but subscapular skinfold thickness z-score was 0.26 s.d. (-0.49 to -0.02; P=0.03) lower in the intervention arm. Maternal dietary GL (-35.34; -48.0 to -22.67; P<0.001) and saturated fat intake (-1.93% energy; -2.64 to -1.22; P<0.001) were reduced in the intervention arm at 6 months postpartum. Causal mediation analysis suggested that lower infant subscapular skinfold thickness was partially mediated by changes in antenatal maternal diet and GWG rather than postnatal diet. CONCLUSIONS: This study provides evidence from follow-up of a randomised controlled trial that a maternal behavioural intervention in obese pregnant women has the potential to reduce infant adiposity and to produce a sustained improvement in maternal diet at 6 months postpartum.


Assuntos
Adiposidade/fisiologia , Desenvolvimento Infantil/fisiologia , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/prevenção & controle , Período Pós-Parto/fisiologia , Complicações na Gravidez/prevenção & controle , Fenômenos Fisiológicos da Nutrição Pré-Natal , Aumento de Peso/fisiologia , Adulto , Índice de Massa Corporal , Dieta , Exercício Físico , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Mães , Obesidade/epidemiologia , Obesidade/fisiopatologia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/fisiopatologia , Comportamento de Redução do Risco , Dobras Cutâneas , Inquéritos e Questionários , Reino Unido/epidemiologia
6.
Ultrasound Obstet Gynecol ; 50(6): 736-744, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28337830

RESUMO

OBJECTIVE: To assess the contribution of fetal magnetic resonance imaging (MRI) in fetuses of the MERIDIAN cohort diagnosed with ventriculomegaly (VM) as the only abnormal intracranial finding on antenatal ultrasound. METHODS: This was a subgroup analysis of the MERIDIAN study of fetuses with only VM diagnosed on ultrasound in women who had a subsequent MRI examination within 2 weeks and for whom outcome reference data were available. The diagnostic accuracy of ultrasound and MRI was reported in relation to the severity of VM. The difference in measurements of trigone size on the two imaging methods and the clinical impact of adding MRI to the diagnostic pathway were also studied. RESULTS: In 306 fetuses with VM, ultrasound failed to detect 31 additional brain abnormalities, having an overall diagnostic accuracy of 89.9% for ultrasound, whilst MRI correctly detected 27 of the additional brain abnormalities, having a diagnostic accuracy of 98.7% (P < 0.0001). There were other brain abnormalities in 14/244 fetuses with mild VM on ultrasound (diagnostic accuracy, 94.3%) and MRI correctly diagnosed 12 of these (diagnostic accuracy, 99.2%; P = 0.0005). There was a close agreement between the size of trigones measured on ultrasound and on MRI, with categorical differences in only 16% of cases, showing that MRI did not systematically overestimate or underestimate trigone size. Complete prognostic data were available in 295/306 fetuses and the prognosis category changed after MRI in 69/295 (23.4%) cases. The overall effect of MRI on clinical management was considered to be 'significant', 'major' or 'decisive' in 76/295 (25.8%) cases. CONCLUSION: Our data suggest that a woman carrying a fetus with VM as the only intracranial finding on ultrasound should be offered an adjuvant investigation by MRI for further evaluation. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Ventrículos Cerebrais/anormalidades , Hidrocefalia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ultrassonografia Pré-Natal , Adulto , Ventrículos Cerebrais/anatomia & histologia , Ventrículos Cerebrais/patologia , Feminino , Humanos , Hidrocefalia/patologia , Aumento da Imagem , Gravidez , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Reino Unido
7.
Ultrasound Obstet Gynecol ; 50(6): 753-760, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28436562

RESUMO

OBJECTIVE: To assess the contribution of fetal magnetic resonance imaging (MRI) in fetuses of the MERIDIAN cohort diagnosed with either agenesis or hypogenesis of the corpus callosum (referred to collectively as failed commissuration) on antenatal ultrasound. METHODS: This was a subgroup analysis of the MERIDIAN study of fetuses with failed commissuration (with or without ventriculomegaly) diagnosed on ultrasound in women who had MRI assessment within 2 weeks of ultrasound and for whom outcome reference data were available. The diagnostic accuracy of ultrasound and MRI was studied, as well as indicators of diagnostic confidence and effects on prognosis/clinical management. Appropriate diagnostic confidence was assessed by the score-based weighted average method, which combines diagnostic accuracy with diagnostic confidence data. RESULTS: In the MERIDIAN cohort, 79 fetuses were diagnosed with failed commissuration on ultrasound (55 with agenesis and 24 with hypogenesis of the corpus callosum). The diagnostic accuracy for detecting failed commissuration was 34.2% for ultrasound and 94.9% for MRI (difference, 60.7% (95% CI, 47.6-73.9%), P < 0.0001). The diagnostic accuracy for detecting hypogenesis of the corpus callosum as a discrete entity was 8.3% for ultrasound and 87.5% for MRI, and for detecting agenesis of the corpus callosum as a distinct entity was 40.0% for ultrasound and 92.7% for MRI. There was a statistically significant improvement in 'appropriate' diagnostic confidence when using MRI as assessed by the score-based weighted average method (P < 0.0001). Prognostic information given to the women changed in 36/79 (45.6%) cases after MRI and its overall effect on clinical management was 'significant', 'major' or 'decisive' in 35/79 cases (44.3%). CONCLUSIONS: Our data suggest that any woman whose fetus has failed commissuration as the only intracranial finding detected on ultrasound should have MRI examination for further evaluation. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Agenesia do Corpo Caloso/diagnóstico por imagem , Corpo Caloso/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ultrassonografia Pré-Natal , Adulto , Agenesia do Corpo Caloso/patologia , Corpo Caloso/anatomia & histologia , Feminino , Idade Gestacional , Humanos , Aumento da Imagem , Gravidez , Prognóstico , Estudos Prospectivos
8.
Ultrasound Obstet Gynecol ; 50(6): 745-752, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28397323

RESUMO

OBJECTIVE: To assess the diagnostic and clinical contribution of fetal magnetic resonance imaging (MRI) in fetuses of the MERIDIAN cohort diagnosed with abnormalities of the posterior fossa as the only intracranial abnormality recognized on antenatal ultrasound. METHODS: This was a subgroup analysis of the MERIDIAN study of fetuses with abnormalities of the posterior fossa (with or without ventriculomegaly) diagnosed on antenatal ultrasound in women who had MRI within 2 weeks of ultrasound and for whom outcome reference data were available. The diagnostic accuracy of ultrasound and MRI is reported, as well as indicators of diagnostic confidence and effects on prognosis and clinical management. Appropriate diagnostic confidence was assessed by the score-based weighted average method, which combines diagnostic accuracy with diagnostic confidence data. RESULTS: Abnormalities confined to the posterior fossa according to ultrasound were found in 81 fetuses (67 with parenchymal and 14 with cerebrospinal fluid-containing lesions). The overall diagnostic accuracy for detecting an isolated posterior fossa abnormality was 65.4% for ultrasound and 87.7% for MRI (difference, 22.3% (95% CI, 14.0-30.5%); P < 0.0001). There was an improvement in 'appropriate' diagnostic confidence, as assessed by the score-based weighted average method (P < 0.0001), and a three-fold reduction in 'high confidence but incorrect diagnosis' was achieved using MRI. Prognostic information given to the women changed after MRI in 44% of cases, and the overall effect of MRI on clinical management was considered to be 'significant', 'major' or 'decisive' in 35% of cases. CONCLUSIONS: Our data suggest that any woman whose fetus has a posterior fossa abnormality as the only intracranial finding on ultrasound should have MRI for further evaluation. This is on the basis of improved diagnostic accuracy and confidence, which impacts substantially on the prognostic information given to women as well as their clinical management. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Fossa Craniana Posterior/anormalidades , Hidrocefalia/diagnóstico , Malformações do Sistema Nervoso/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Fossa Craniana Posterior/anatomia & histologia , Fossa Craniana Posterior/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Hidrocefalia/patologia , Imageamento por Ressonância Magnética , Malformações do Sistema Nervoso/patologia , Gravidez , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes
9.
Clin Radiol ; 72(6): 451-457, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28238368

RESUMO

AIM: To measure possible change in diagnostic confidence by performing in utero magnetic resonance imaging (iuMRI) studies on fetuses with brain abnormalities recognised on ultrasonography (US). MATERIALS AND METHODS: The analyses are based on the primary cohort from the prospective MERIDIAN study, which consisted of 570 fetuses with brain abnormalities detected on US, with iuMRI performed within 2 weeks of US and complete outcome reference data. The cohort was recruited between July 2011 and August 2014, and written informed consent was obtained for all participants. They all had indicators of diagnostic confidence measured on US by fetal medicine experts and iuMRI by the reporting radiologists. Three assessments were carried out using the conventional uncorrected (C2-C1%) method, the conventional (C2-C1%) with the Omary correction, and the score-based weighted average method. RESULTS: All three assessments showed statistically significant (p<0·0001) positive effects indicating that iuMRI was potentially beneficial when included in the diagnostic pathway for prenatal structural brain anomalies (in terms of diagnostic confidence). CONCLUSION: These results strongly support the routine clinical use of iuMRI as an adjunct to US when assessing fetuses with structural brain abnormalities.


Assuntos
Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Feto/anormalidades , Feto/diagnóstico por imagem , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Intervalos de Confiança , Feminino , Humanos , Gravidez , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/estatística & dados numéricos , Estudos Prospectivos
10.
Am J Transplant ; 16(10): 2781-2794, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27005321

RESUMO

Purinergic signaling has been recognized as playing an important role in inflammation, angiogenesis, malignancy, diabetes and neural transmission. Activation of signaling pathways downstream from purinergic receptors may also be implicated in transplantation and related vascular injury. Following transplantation, the proinflammatory "danger signal" adenosine triphosphate (ATP) is released from damaged cells and promotes proliferation and activation of a variety of immune cells. Targeting purinergic signaling pathways may promote immunosuppression and ameliorate inflammation. Under pathophysiological conditions, nucleotide-scavenging ectonucleotidases CD39 and CD73 hydrolyze ATP, ultimately, to the anti-inflammatory mediator adenosine. Adenosine suppresses proinflammatory cytokine production and is associated with improved graft survival and decreased severity of graft-versus-host disease. Furthermore, purinergic signaling is involved both directly and indirectly in the mechanism of action of several existing immunosuppressive drugs, such as calcineurin inhibitors and mammalian target of rapamycin inhibitors. Targeting of purinergic receptor pathways, particularly in the setting of combination therapies, could become a valuable immunosuppressive strategy in transplantation. This review focuses on the role of the purinergic signaling pathway in transplantation and immunosuppression and explores possible future applications in clinical practice.


Assuntos
Imunossupressores/uso terapêutico , Transplante de Órgãos , Purinas/metabolismo , Receptores Purinérgicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Humanos
11.
Am J Transplant ; 15(2): 358-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25612490

RESUMO

Galactosyl-transferase KO (GalT-KO) pigs represent a potential solution to xenograft rejection, particularly in the context of additional genetic modifications. We have performed life supporting kidney xenotransplantation into baboons utilizing GalT-KO pigs transgenic for human CD55/CD59/CD39/HT. Baboons received tacrolimus, mycophenolate mofetil, corticosteroids and recombinant human C1 inhibitor combined with cyclophosphamide or bortezomib with or without 2-3 plasma exchanges. One baboon received a control GalT-KO xenograft with the latter immunosuppression. All immunosuppressed baboons rejected the xenografts between days 9 and 15 with signs of acute humoral rejection, in contrast to untreated controls (n = 2) that lost their grafts on days 3 and 4. Immunofluorescence analyses showed deposition of IgM, C3, C5b-9 in rejected grafts, without C4d staining, indicating classical complement pathway blockade but alternate pathway activation. Moreover, rejected organs exhibited predominantly monocyte/macrophage infiltration with minimal lymphocyte representation. None of the recipients showed any signs of porcine endogenous retrovirus transmission but some showed evidence of porcine cytomegalovirus (PCMV) replication within the xenografts. Our work indicates that the addition of bortezomib and plasma exchange to the immunosuppressive regimen did not significantly prolong the survival of multi-transgenic GalT-KO renal xenografts. Non-Gal antibodies, the alternative complement pathway, innate mechanisms with monocyte activation and PCMV replication may have contributed to rejection.


Assuntos
Ácidos Borônicos/uso terapêutico , Proteína Inibidora do Complemento C1/uso terapêutico , Galactosiltransferases/genética , Sobrevivência de Enxerto/fisiologia , Xenoenxertos , Transplante de Rim , Troca Plasmática , Pirazinas/uso terapêutico , Animais , Animais Geneticamente Modificados , Doenças Autoimunes , Bortezomib , Citomegalovirus/fisiologia , Galactosiltransferases/deficiência , Técnicas de Inativação de Genes , Imunidade Inata/fisiologia , Imunossupressores/uso terapêutico , Rim/cirurgia , Rim/virologia , Modelos Animais , Papio anubis , Sus scrofa , Replicação Viral/fisiologia
12.
Clin Exp Allergy ; 45(6): 1126-37, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25728362

RESUMO

BACKGROUND: The suppressive mechanism of regulatory T cells (Tregs) has remained incompletely clarified. Recent studies found that CD39 expressed by Tregs may participate in the immunoregulatory role of Tregs. CD39-induced ATP hydrolysis and/or adenosine generation contribute to the suppressive mechanism of Tregs. Previous studies suggested that ATP is involved in allergic airway inflammation by acting on type 2 purinergic (P2) receptors, but the role of CD39 and CD39(+) Tregs in allergic airway inflammation has not been elaborated. OBJECTIVE: To investigate the role and underlying mechanism of CD39 expression by Tregs in allergic airway inflammation. METHODS: A model of allergic asthma was developed with ovalbumin-alum in female Cd39 wild type (Cd39(+/+) ) and deficient (Cd39(-/-) ) C57BL/6 mice. Foxp3-GFP knock-in Cd39(+/+) and Cd39(-/-) mice were used to sort CD4(+) GFP(+) cells (Tregs) for exploring the role of CD39 expression by Tregs in allergic asthma. The effects of modulating CD39 activity with ARL67156 (inhibitor) or apyrase were also observed. RESULTS: ARL67156 greatly worsened airway inflammation including increased lung inflammatory cells infiltration, goblet cell hyperplasia, and higher levels of Th2 and Th17 cytokines in bronchoalveolar lavage fluid (BALF), accompanied by an increment in transcription factor (GATA-3 and RORγt) and P2R (P2Y2, P2Y4 and P2Y6) mRNA expression in lungs. This potentiating effect was rescued by intratracheal injection of apyrase. Airway inflammation was markedly increased in Cd39(-/-) mice compared to Cd39(+/+) mice. In contrast to CD39(-) Tregs, CD39(+) Tregs showed stronger suppressive effects on airway inflammation. In vitro suppression assay suggested that CD39(+) Tregs have more potent suppressive effect on cytokines secretion from CD4(+) CD25(-) responder T cells and the inhibitory effects were reduced by addition of adenosine A2A receptor antagonist. CONCLUSION: CD39 expressed on Tregs participates in the regulation of limiting allergic airway inflammation by regulating extracellular ATP and/or adenosine. CD39 may represent a new therapeutic target for asthma.


Assuntos
Antígenos CD/metabolismo , Apirase/metabolismo , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Adenosina/farmacologia , Animais , Antígenos CD/genética , Apirase/genética , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Imunofenotipagem , Imunossupressores/farmacologia , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Contagem de Linfócitos , Camundongos , Camundongos Knockout , Hipersensibilidade Respiratória/genética , Hipersensibilidade Respiratória/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos
13.
J Obstet Gynaecol ; 35(2): 168-72, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25058716

RESUMO

Choice of a medical or surgical method of termination for fetal anomaly (TFA) is advocated in national guidelines based on a similar risk profile. We investigated whether women are offered a choice of method, by surveying members of a UK parent support organisation. An online questionnaire was designed to examine respondents' experience of TFA. A total of 351 responses were included in the final analysis. TFAs after 24 weeks' gestation and selective reductions were excluded. Mean gestational age at TFA was 17 weeks; 14% (n = 50) were offered a choice of method, falling to 8% (n = 19) after 14 weeks' gestation. Overall, 78% (n = 275) underwent medical TFA with 88% stating they chose it because it was the only method offered; 60% (n = 30) of those offered a choice had a surgical TFA. Our survey suggests that women having TFA are not offered a choice of method. Service delivery should be improved to meet national guidance and women's needs.


Assuntos
Aborto Eugênico/métodos , Aberrações Cromossômicas , Anormalidades Congênitas , Participação do Paciente , Inglaterra , Feminino , Idade Gestacional , Fidelidade a Diretrizes , Humanos , Guias de Prática Clínica como Assunto , Gravidez , Inquéritos e Questionários
14.
Am J Transplant ; 14(6): 1300-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24842781

RESUMO

The instant blood-mediated inflammatory reaction (IBMIR) is a major obstacle to the engraftment of intraportal pig islet xenografts in primates. Higher expression of the galactose-α1,3-galactose (αGal) xenoantigen on neonatal islet cell clusters (NICC) than on adult pig islets may provoke a stronger reaction, but this has not been tested in the baboon model. Here, we report that WT pig NICC xenografts triggered profound IBMIR in baboons, with intravascular clotting and graft destruction occurring within hours, which was not prevented by anti-thrombin treatment. In contrast, IBMIR was minimal when recipients were immunosuppressed with a clinically relevant protocol and transplanted with NICC from αGal-deficient pigs transgenic for the human complement regulators CD55 and CD59. These genetically modified (GM) NICC were less susceptible to humoral injury in vitro than WT NICC, inducing significantly less complement activation and thrombin generation when incubated with baboon platelet-poor plasma. Recipients of GM NICC developed a variable anti-pig antibody response, and examination of the grafts 1 month after transplant revealed significant cell-mediated rejection, although scattered insulin-positive cells were still present. Our results indicate that IBMIR can be attenuated in this model, but long-term graft survival may require more effective immunosuppression or further donor genetic modification.


Assuntos
Sangue , Rejeição de Enxerto , Transplante das Ilhotas Pancreáticas , Transplante Heterólogo , Animais , Anticorpos/sangue , Bovinos , Papio
15.
Diabet Med ; 31(8): 963-70, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24798080

RESUMO

AIM: To examine the prediction of gestational diabetes in obese women using routine clinical measures and measurement of biomarkers related to insulin resistance in the early second trimester. METHODS: A total of 117 obese pregnant women participating in a pilot trial of a complex intervention of dietary advice and physical activity were studied. Blood samples were obtained at recruitment (15⁺°-17⁺6 weeks' gestation) and demographic, clinical history and anthropometric measures recorded. The biomarkers analysed were plasma lipids (HDL cholesterol, LDL cholesterol, triglycerides), high-sensitivity C-reactive protein, alanine transaminase, aspartate transaminase, ferritin, fructosamine, insulin, adiponectin, tissue plasminogen activator, interleukin-6, visfatin and leptin. Univariate and logistic regression analyses were performed to determine independent predictors and area under the receiver-operating curve was calculated for the model. RESULTS: Of the 106 participants included in the analysis, 29 (27.4%) developed gestational diabetes. Participants with gestational diabetes were older (P = 0.002), more often of parity ≥ 2, had higher systolic (P = 0.02) and diastolic blood pressure (P = 0.02) and were more likely to be black (P = 0.009). Amongst the blood biomarkers measured, plasma adiponectin alone remained independently associated with gestational diabetes in adjusted models (P = 0.002). The area under the receiver-operating curve for clinical factors alone (0.760) increased significantly (area under the curve 0.834, chi-square statistic (1) = 4.00, P = 0.046) with the addition of adiponectin. CONCLUSIONS: A combination of routinely measured clinical factors and adiponectin measured in the early second trimester in obese women may provide a useful approach to the prediction of gestational diabetes. Validation in a large prospective study is required to determine the usefulness of this algorithm in clinical practice.


Assuntos
Diabetes Gestacional/prevenção & controle , Dieta Redutora , Atividade Motora , Obesidade/terapia , Complicações na Gravidez/terapia , Fenômenos Fisiológicos da Nutrição Pré-Natal , Adiponectina/sangue , Adolescente , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Terapia Combinada , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/etiologia , Feminino , Humanos , Obesidade/sangue , Obesidade/dietoterapia , Obesidade/fisiopatologia , Projetos Piloto , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/dietoterapia , Complicações na Gravidez/fisiopatologia , Segundo Trimestre da Gravidez , Sensibilidade e Especificidade , Regulação para Cima , Adulto Jovem
16.
BJOG ; 121(10): 1302-10; discussion 1311, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24835579

RESUMO

OBJECTIVE: To determine whether a midwife-led intervention improved preparation for twin parenting and maternal psychosocial outcome. DESIGN: Randomised controlled trial. SETTING: Two maternity units in North East England. POPULATION: A cohort of 162 women with uncomplicated twin pregnancy. METHODS: Self-completion questionnaire at multiple time points. MAIN OUTCOME MEASURES: The primary outcome was probable postnatal depression (measured with the Edinburgh Postnatal Depression Scale, EPDS) 26 weeks after delivery. Secondary outcomes included preparation for parenting, maternal anxiety, parenting stress, and maternal wellbeing. RESULTS: The mean maternal EPDS scores at 26 weeks after delivery were 5.4 (SD 4.5) in the twin intervention (TI) group and 6.9 (SD 5.5) in the twin control (TC) group, and the mean difference between the groups was 1.5 (95% confidence interval, 95% CI, -0.2 to 3.3). The relative risk (RR) of having probable depression in the TI group compared with the TC group at 26 weeks was 0.48 (95% CI 0.19-1.20) for mothers and 0.84 (95% CI 0.42-1.70) for fathers. There were no statistically significant differences in maternal anxiety or parenting stress. TI mothers reported increased maternal wellbeing, reaction to motherhood, family support, mood, and greater self-confidence 26 weeks after delivery, and felt more prepared for parenting. CONCLUSION: As a result of the limited sample size, the study was unable to detect a difference in maternal depression using the maternal EPDS mean score. The antenatal preparation for parenting programme did not improve postnatal maternal anxiety or parenting stress; however, it did improve postnatal maternal wellbeing, mood, self-confidence, reaction to motherhood, and better prepared mothers to parent twin infants. Midwives have a key role in preparing mothers to parent twins.


Assuntos
Depressão Pós-Parto/epidemiologia , Bem-Estar Materno/psicologia , Tocologia , Poder Familiar/psicologia , Pais/psicologia , Estresse Psicológico/epidemiologia , Adaptação Psicológica , Transtornos de Ansiedade/epidemiologia , Inglaterra , Feminino , Humanos , Masculino , Gravidez , Inquéritos e Questionários , Gêmeos
17.
BJOG ; 121(6): 686-99, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24738894

RESUMO

BACKGROUND: Measurements of amniotic fluid volume are used for pregnancy surveillance despite a lack of evidence for their predictive ability. OBJECTIVE: To evaluate the association and predictive value of ultrasound measurements of amniotic fluid volume for adverse pregnancy outcome. SEARCH STRATEGY: Electronic databases (inception to October 2011), reference lists, hand searching of journals, contact with experts. SELECTION CRITERIA: Studies comparing measurements of amniotic fluid volume with adverse outcome, excluding pre-labour ruptured membranes or congenital/structural anomalies. DATA COLLECTION: Data on study characteristics, design, quality. Random effects meta-analysis to estimate summary odds ratios (prognostic association) and summary sensitivity, specificity and likelihood ratios (predictive ability). MAIN RESULTS: Forty-three studies (244,493 fetuses) were included demonstrating a strong association between oligohydramnios (varying definitions) and birthweight <10th centile (summary odds ratio [OR] 6.31, 95% confidence interval [95% CI] 4.15-9.58; high-risk population [author definition] n = 6 studies, 28,510 fetuses), and mortality (neonatal death any population summary OR 8.72, 95% CI 2.43-31.26; n = 6 studies, 55,735 fetuses; and perinatal mortality high-risk population summary OR 11.54, 95% CI 4.05-32.9; n = 2 studies, 27;891 fetuses). There was a strong association between polyhydramnios (maximum pool depth >8 cm or amniotic fluid index ≥25 cm) and birthweight >90th centile (OR 11.41, 95% CI 7.09-18.36; n = 1 study, 3960 fetuses). Despite strong associations, predictive accuracy for perinatal outcome was poor. AUTHOR'S CONCLUSION: Current evidence suggests that oligohydramnios is strongly associated with being small for gestational age and mortality, and polyhydramnios with birthweight >90th centile. Despite strong associations with poor outcome, they do not accurately predict outcome risk for individuals.


Assuntos
Líquido Amniótico/diagnóstico por imagem , Oligo-Hidrâmnio/diagnóstico por imagem , Poli-Hidrâmnios/diagnóstico por imagem , Ultrassonografia Pré-Natal , Peso ao Nascer , Feminino , Humanos , Recém-Nascido , Razão de Chances , Oligo-Hidrâmnio/mortalidade , Poli-Hidrâmnios/mortalidade , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Prognóstico , Reprodutibilidade dos Testes , Ultrassonografia Pré-Natal/métodos
18.
Anaesthesia ; 69(5): 458-67, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24738803

RESUMO

We have compared fetal heart rate patterns, Apgar scores and umbilical cord gas values following initiation of labour analgesia using either combined spinal-epidural or epidural. One hundred and fifteen healthy women requesting neuraxial analgesia in the first stage of labour were randomly assigned to receive either combined spinal-epidural (n = 62) or epidural analgesia (n = 53). Fetal heart rate traces, recorded for 30 min before and 60 min after neuraxial block, were categorised as normal, suspicious or pathological according to national guidelines. Sixty-one fetal heart rate tracings were analysed in the combined spinal-epidural group and 52 in the epidural group. No significant differences were found in fetal heart rate patterns, Apgar scores or umbilical artery and vein acid-base status between groups. However, in both combined spinal-epidural and epidural groups, there was a significant increase in the incidence of abnormal fetal heart rate patterns following neuraxial analgesia (p < 0.0001); two before compared with eight after analgesia in the combined spinal-epidural group and zero before compared with 11 after in the epidural group. These changes comprised increased decelerations (p = 0.0045) (combined spinal-epidural group nine before and 14 after analgesia, epidural group four before and 16 after), increased late decelerations (p < 0.0001) (combined spinal-epidural group zero before and seven after analgesia, epidural group zero before and eight after), and a reduction in acceleration rate (p = 0.034) (combined spinal-epidural group mean (SD) 12.2 (6.7) h(-1) before and 9.9 (6.1) h(-1) after analgesia, epidural group 11.0 (7.3) h(-1) before and 8.4 (5.9) h(-1) after). These fetal heart rate changes did not affect neonatal outcome in this healthy population.


Assuntos
Analgesia Epidural/efeitos adversos , Analgesia Obstétrica/efeitos adversos , Índice de Apgar , Quimioterapia Combinada/efeitos adversos , Frequência Cardíaca Fetal/efeitos dos fármacos , Cordão Umbilical/efeitos dos fármacos , Adulto , Analgesia Epidural/métodos , Analgesia Obstétrica/métodos , Análise de Variância , Método Duplo-Cego , Quimioterapia Combinada/métodos , Feminino , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Recém-Nascido , Injeções Espinhais/efeitos adversos , Gravidez , Estudos Prospectivos
19.
Mol Hum Reprod ; 19(11): 727-36, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23775458

RESUMO

Endothelial-dependent regulation of vascular tone occurs in part via protein kinase G1α-mediated changes in smooth muscle myofilament sensitivity to Ca(2+). Tissue-specific differences in PKG-dependent relaxation have been attributed to altered expression of myofilament-associated proteins that are substrates for PKG binding. These include the alternative splicing of the myosin targeting subunit (MYPT1) of myosin light chain phosphatase to yield leucine zipper positive (LZ(+)) and negative (LZ(-)) isovariants, with the former being required for PKG-mediated relaxation, and/or altered expressions of telokin, vasodilator-stimulated phosphoprotein (VASP) or heat shock protein Hsp20. During human pregnancy the uterine and placental circulations remain distinct entities and, as such, their mechanisms of vascular tone regulation may differ. Indeed, the sensitivity of myometrial arteries to endothelial-dependent agonists has been suggested to be greater than that of placental arteries. We tested the hypothesis that this was related to tissue-specific changes in PKG-mediated myofilament Ca(2+)-desensitization and/or the expressions of PKG-interacting myofilament-associated proteins. Permeabilized human placental and myometrial arteries were constricted with maximal activating Ca(2+) (pCa 4.5), or sub-maximal Ca(2+) (pCa 6.7) and the thrombane mimetic U46619, and exposed to 8-Br-cGMP. In each case, relaxation was significantly greater in myometrial arteries (e.g. relaxation in pCa 4.5 to 8-Br-cGMP was 49 ± 9.7%, n = 7) than placental arteries (relaxation of 23 ± 6.6%, n = 6, P < 0.05). MYPT1 protein levels, or MYPT1 LZ(+)/LZ(-) mRNA ratios, were similar for both artery types. Of other proteins examined, only Hsp20 expression was significantly elevated in myometrial arteries than placental arteries. These results demonstrate that the reduced human placental artery relaxation to PKG stimulation lies partly at the level of myofilament (de)activation and may be related to a lower expression of Hsp20 than in myometrial arteries.


Assuntos
Cálcio/metabolismo , Miofibrilas/metabolismo , Miométrio/irrigação sanguínea , Placenta/irrigação sanguínea , Artéria Uterina/fisiologia , Vasodilatação/fisiologia , Adulto , Biópsia , Feminino , Proteínas de Choque Térmico HSP20/genética , Proteínas de Choque Térmico HSP20/metabolismo , Humanos , Miofibrilas/patologia , Miografia , Miométrio/metabolismo , Miométrio/patologia , Fosfatase de Miosina-de-Cadeia-Leve/genética , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Placenta/metabolismo , Placenta/patologia , Gravidez , Adulto Jovem
20.
Allergy ; 68(4): 472-80, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23452076

RESUMO

BACKGROUND: Extracellular Adenosine-5'-Triphosphate (ATP) is known to accumulate in the lung, following allergen challenge, and contributes via activation of purinergic receptors on dendritic cells (DC), to the development of allergic airway inflammation (AAI). Extracellular ATP levels in the airways are normally tightly regulated by CD39. This ectonucleotidase is highly expressed by DC purified from skin (Langerhans cells) and bone marrow, and has been shown to modulate DC adaptive/haptenic immune responses. In this study, we have evaluated the impact of Cd39 deletion and associated perturbation of purinergic signaling in AAI. METHODS: Standard ovalbumin (OVA)-alum and house dust mite (HDM) bone marrow-derived DC (BMDC)-dependent models of AAI were used to study effects of Cd39. Migration assays, time lapse microscopy, and T-cell priming assays were further used to determine functional relevance of Cd39 expression on BMDC in the setting of immune and Th2-mediated responses in these models. RESULTS: Cd39(-/-) mice exhibited marked increases in BALF ATP levels but paradoxically exhibited limited AAI in both OVA-alum and HDM models. These pathophysiological abnormalities were associated with decreased myeloid DC activation and chemotaxis toward ATP, and were linked to purinergic receptor desensitization responses. Further, Cd39(-/-) DCs exhibited limited capacity to both prime Th2 responses and form stable immune synaptic interactions with OVA-transgenic naïve T cells. CONCLUSIONS: Cd39-deficient DCs exhibit limited capacity to induce Th2 immunity in a DC-driven model of AAI in vivo. Our data demonstrate a role of CD39 and perturbed purinergic signaling in models of AAI.


Assuntos
Antígenos CD/genética , Apirase/genética , Asma/genética , Asma/imunologia , Trifosfato de Adenosina/biossíntese , Compostos de Alúmen , Animais , Antígenos CD/metabolismo , Apirase/deficiência , Apirase/metabolismo , Movimento Celular/genética , Movimento Celular/imunologia , Citocinas/biossíntese , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Pulmão/imunologia , Pulmão/metabolismo , Camundongos , Camundongos Knockout , Ovalbumina/imunologia , Pyroglyphidae/imunologia , Células Th2/imunologia , Células Th2/metabolismo
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