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1.
PLoS Pathog ; 19(8): e1011274, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37549143

RESUMO

Zika virus (ZIKV) can be transmitted vertically from mother to fetus during pregnancy, resulting in a range of outcomes including severe birth defects and fetal/infant death. Potential pathways of vertical transmission in utero have been proposed but remain undefined. Identifying the timing and routes of vertical transmission of ZIKV may help us identify when interventions would be most effective. Furthermore, understanding what barriers ZIKV overcomes to effect vertical transmission may help improve models for evaluating infection by other pathogens during pregnancy. To determine the pathways of vertical transmission, we inoculated 12 pregnant rhesus macaques with an African-lineage ZIKV at gestational day 30 (term is 165 days). Eight pregnancies were surgically terminated at either seven or 14 days post-maternal infection. Maternal-fetal interface and fetal tissues and fluids were collected and evaluated for ZIKV using RT-qPCR, in situ hybridization, immunohistochemistry, and plaque assays. Four additional pregnant macaques were inoculated and terminally perfused with 4% paraformaldehyde at three, six, nine, or ten days post-maternal inoculation. For these four cases, the entire fixed pregnant uterus was evaluated with in situ hybridization for ZIKV RNA. We determined that ZIKV can reach the MFI by six days after infection and infect the fetus by ten days. Infection of the chorionic membrane and the extraembryonic coelomic fluid preceded infection of the fetus and the mesenchymal tissue of the placental villi. We did not find evidence to support a transplacental route of ZIKV vertical transmission via infection of syncytiotrophoblasts or villous cytotrophoblasts. The pattern of infection observed in the maternal-fetal interface provides evidence of paraplacental vertical ZIKV transmission through the chorionic membrane, the outer layer of the fetal membranes.


Assuntos
Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Humanos , Animais , Gravidez , Feminino , Zika virus/genética , Macaca mulatta , Placenta , Complicações Infecciosas na Gravidez/metabolismo , Morte Fetal , Transmissão Vertical de Doenças Infecciosas , Membranas Extraembrionárias/metabolismo
2.
PLoS Pathog ; 19(3): e1011282, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36976812

RESUMO

In the 2016 Zika virus (ZIKV) pandemic, a previously unrecognized risk of birth defects surfaced in babies whose mothers were infected with Asian-lineage ZIKV during pregnancy. Less is known about the impacts of gestational African-lineage ZIKV infections. Given high human immunodeficiency virus (HIV) burdens in regions where African-lineage ZIKV circulates, we evaluated whether pregnant rhesus macaques infected with simian immunodeficiency virus (SIV) have a higher risk of African-lineage ZIKV-associated birth defects. Remarkably, in both SIV+ and SIV- animals, ZIKV infection early in the first trimester caused a high incidence (78%) of spontaneous pregnancy loss within 20 days. These findings suggest a significant risk for early pregnancy loss associated with African-lineage ZIKV infection and provide the first consistent ZIKV-associated phenotype in macaques for testing medical countermeasures.


Assuntos
Aborto Espontâneo , Complicações Infecciosas na Gravidez , Vírus da Imunodeficiência Símia , Infecção por Zika virus , Zika virus , Gravidez , Feminino , Animais , Humanos , Zika virus/genética , Macaca mulatta , Primeiro Trimestre da Gravidez
3.
Am J Obstet Gynecol ; 228(2): 187-202, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35973475

RESUMO

The importance of a fully functioning placenta for a good pregnancy outcome is unquestioned. Loss of function can lead to pregnancy complications and is often detected by a thorough placental pathologic examination. Placental pathology has advanced the science and practice of obstetrics and neonatal-perinatal medicine by classifying diseases according to underlying biology and specific patterns of injury. Many past obstacles have limited the incorporation of placental findings into both clinical studies and day-to-day practice. Limitations have included variability in the nomenclature used to describe placental lesions, a shortage of perinatal pathologists fully competent to analyze placental specimens, and a troubling lack of understanding of placental diagnoses by clinicians. However, the potential use of placental pathology for phenotypic classification, improved understanding of the biology of adverse pregnancy outcomes, the development of treatment and prevention, and patient counseling has never been greater. This review, written partly in response to a recent critique published in a major obstetrics-gynecology journal, reexamines the role of placental pathology by reviewing current concepts of biology; explaining the most recent terminology; emphasizing the usefulness of specific diagnoses for obstetrician-gynecologists, neonatologists, and patients; previewing upcoming changes in recommendations for placental submission; and suggesting future improvements. These improvements should include further consideration of overall healthcare costs, cost-effectiveness, the clinical value added of placental assessment, improvements in placental pathology education and practice, and leveraging of placental pathology to identify new biomarkers of disease and evaluate novel therapies tailored to specific clinicopathologic phenotypes of both women and infants.


Assuntos
Placenta , Complicações na Gravidez , Humanos , Gravidez , Feminino , Placenta/patologia , Resultado da Gravidez
4.
Am J Physiol Gastrointest Liver Physiol ; 323(6): G571-G585, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36194131

RESUMO

Colorectal cancer (CRC) is a leading cause of cancer-related death. There is an urgent need for new methods of early CRC detection and monitoring to improve patient outcomes. Extracellular vesicles (EVs) are secreted, lipid-bilayer bound, nanoparticles that carry biological cargo throughout the body and in turn exhibit cancer-related biomarker potential. RNA binding proteins (RBPs) are posttranscriptional regulators of gene expression that may provide a link between host cell gene expression and EV phenotypes. Insulin-like growth factor 2 RNA binding protein 1 (IGF2BP1/IMP1) is an RBP that is highly expressed in CRC with higher levels of expression correlating with poor prognosis. IMP1 binds and potently regulates tumor-associated transcripts that may impact CRC EV phenotypes. Our objective was to test whether IMP1 expression levels impact EV secretion and/or cargo. We used RNA sequencing, in vitro CRC cell lines, ex vivo colonoid models, and xenograft mice to test the hypothesis that IMP1 influences EV secretion and/or cargo in human CRC. Our data demonstrate that IMP1 modulates the RNA expression of transcripts associated with extracellular vesicle pathway regulation, but it has no effect on EV secretion levels in vitro or in vivo. Rather, IMP1 appears to affect EV regulation by directly entering EVs in a transformation-dependent manner. These findings suggest that IMP1 has the ability to shape EV cargo in human CRC, which could serve as a diagnostic/prognostic circulating tumor biomarker.NEW & NOTEWORTHY This work demonstrates that the RNA binding protein IGF2BP1/IMP1 alters the transcript profile of colorectal cancer cell (CRC) mRNAs from extracellular vesicle (EV) pathways. IMP1 does not alter EV production or secretion in vitro or in vivo, but rather enters CRC cells where it may further impact EV cargo. Our work shows that IMP1 has the ability to shape EV cargo in human CRC, which could serve as a diagnostic/prognostic circulating tumor biomarker.


Assuntos
Neoplasias Colorretais , Vesículas Extracelulares , Humanos , Camundongos , Animais , Vesículas Extracelulares/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , RNA Mensageiro/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia
5.
Biol Reprod ; 107(6): 1517-1527, 2022 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-36018823

RESUMO

Identification of placental dysfunction in early pregnancy with noninvasive imaging could be a valuable tool for assessing maternal and fetal risk. Dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) can be a powerful tool for interrogating placenta health. After inoculation with Zika virus or sham inoculation at gestation age (GA) 45 or 55 days, animals were imaged up to three times at GA65, GA100, and GA145. DCE MRI images were acquired at all imaging sessions using ferumoxytol, an iron nanoparticle-based contrast agent, and analyzed for placental intervillous blood flow, number of perfusion domains, and perfusion domain volume. Cesarean section was performed at GA155, and the placenta was photographed and dissected for histopathology. Photographs were used to align cotyledons with estimated perfusion domains from MRI, allowing comparison of estimated cotyledon volume to pathology. Monkeys were separated into high and low pathology groups based on the average number of pathologies present in the placenta. Perfusion domain flow, volume, and number increased through gestation, and total blood flow increased with gestation for both low pathology and high pathology groups. A statistically significant decrease in perfusion domain volume associated with pathology was detected at all gestational ages. Individual perfusion domain flow comparisons demonstrated a statistically significant decrease with pathology at GA100 and GA145, but not GA65. Since ferumoxytol is currently used to treat anemia during human pregnancy and as an off-label MRI contrast agent, future transition of this work to human pregnancy may be possible.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Gravidez , Feminino , Humanos , Lactente , Placenta/irrigação sanguínea , Óxido Ferroso-Férrico , Macaca mulatta , Meios de Contraste , Cotilédone , Cesárea , Imageamento por Ressonância Magnética/métodos , Perfusão , Infecção por Zika virus/patologia
6.
J Virol ; 95(16): e0222020, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34076485

RESUMO

Following the Zika virus (ZIKV) outbreak in the Americas, ZIKV was causally associated with microcephaly and a range of neurological and developmental symptoms, termed congenital Zika syndrome (CZS). The viruses responsible for this outbreak belonged to the Asian lineage of ZIKV. However, in vitro and in vivo studies assessing the pathogenesis of African-lineage ZIKV demonstrated that African-lineage isolates often replicated to high titers and caused more-severe pathology than Asian-lineage isolates. To date, the pathogenesis of African-lineage ZIKV in a translational model, particularly during pregnancy, has not been rigorously characterized. Here, we infected four pregnant rhesus macaques with a low-passage-number strain of African-lineage ZIKV and compared its pathogenesis to those for a cohort of four pregnant rhesus macaques infected with an Asian-lineage isolate and a cohort of mock-inoculated controls. The viral replication kinetics for the two experimental groups were not significantly different, and both groups developed robust neutralizing antibody titers above levels considered to be protective. There was no evidence of significant fetal head growth restriction or gross fetal harm at delivery (1 to 1.5 weeks prior to full term) in either group. However, a significantly higher burden of ZIKV viral RNA (vRNA) was found in the maternal-fetal interface tissues of the macaques exposed to an African-lineage isolate. Our findings suggest that ZIKV of any genetic lineage poses a threat to pregnant individuals and their infants. IMPORTANCE ZIKV was first identified in 1947 in Africa, but most of our knowledge of ZIKV is based on studies of the distinct Asian genetic lineage, which caused the outbreak in the Americas in 2015 to 2016. In its most recent update, the WHO stated that improved understanding of African-lineage ZIKV pathogenesis during pregnancy must be a priority. The recent detection of African-lineage isolates in Brazil underscores the need to understand the impact of these viruses. Here, we provide the first comprehensive assessment of African-lineage ZIKV infection during pregnancy in a translational nonhuman primate model. We show that African-lineage isolates replicate with kinetics similar to those of Asian-lineage isolates and can infect the placenta. However, there was no evidence of more-severe outcomes with African-lineage isolates. Our results highlight both the threat that African-lineage ZIKV poses to pregnant individuals and their infants and the need for epidemiological and translational in vivo studies with African-lineage ZIKV.


Assuntos
Placenta/virologia , Complicações Infecciosas na Gravidez/virologia , Replicação Viral , Infecção por Zika virus/virologia , Zika virus/fisiologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Modelos Animais de Doenças , Feminino , Desenvolvimento Fetal , Cinética , Macaca mulatta , Placenta/patologia , Gravidez , Zika virus/classificação , Zika virus/imunologia
7.
Am J Obstet Gynecol ; 226(1): 130.e1-130.e11, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364844

RESUMO

BACKGROUND: Prenatal alcohol exposure is the most common cause of birth defects and intellectual disabilities and can increase the risk of stillbirth and negatively impact fetal growth. OBJECTIVE: To determine the effect of early prenatal alcohol exposure on nonhuman primate placental function and fetal growth. We hypothesized that early chronic prenatal alcohol would alter placental perfusion and oxygen availability that adversely affects fetal growth. STUDY DESIGN: Rhesus macaques self-administered 1.5 g/kg/d of ethanol (n=12) or isocaloric maltose-dextrin (n=12) daily before conception through the first 60 days of gestation (term is approximately 168 days). All animals were serially imaged with Doppler ultrasound to measure fetal biometry, uterine artery volume blood flow, and placental volume blood flow. Following Doppler ultrasound, all animals underwent both blood oxygenation level-dependent magnetic resonance imaging to characterize placental blood oxygenation and dynamic contrast-enhanced magnetic resonance imaging to quantify maternal placental perfusion. Animals were delivered by cesarean delivery for placental collection and fetal necropsy at gestational days 85 (n=8), 110 (n=8), or 135 (n=8). Histologic and RNA-sequencing analyses were performed on collected placental tissue. RESULTS: Placental volume blood flow was decreased at all gestational time points in ethanol-exposed vs control animals, but most significantly at gestational day 110 by Doppler ultrasound (P<.05). A significant decrease in total volumetric blood flow occurred in ethanol-exposed vs control animals on dynamic contrast-enhanced magnetic resonance imaging at both gestation days 110 and 135 (P<.05); moreover, a global reduction in T2∗, high blood deoxyhemoglobin concentration, occurred throughout gestation (P<.05). Similarly, evidence of placental ischemic injury was notable by histologic analysis, which revealed a significant increase in microscopic infarctions in ethanol-exposed, not control, animals, largely present at middle to late gestation. Fetal biometry and weight were decreased in ethanol-exposed vs control animals, but the decrease was not significant. Analysis with RNA sequencing suggested the involvement of the inflammatory and extracellular matrix response pathways. CONCLUSION: Early chronic prenatal alcohol exposure significantly diminished placental perfusion at mid to late gestation and also significantly decreased the oxygen supply to the fetal vasculature throughout pregnancy, these findings were associated with the presence of microscopic placental infarctions in the nonhuman primate. Although placental adaptations may compensate for early environmental perturbations to fetal growth, placental blood flow and oxygenation were reduced, consistent with the evidence of placental ischemic injury.


Assuntos
Etanol/efeitos adversos , Macaca mulatta , Efeitos Tardios da Exposição Pré-Natal/etiologia , Animais , Modelos Animais de Doenças , Etanol/farmacologia , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Humanos , Placenta/efeitos dos fármacos , Gravidez
8.
Biol Reprod ; 104(4): 924-934, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33459759

RESUMO

Abnormally increased angiotensin II activity related to maternal angiotensinogen (AGT) genetic variants, or aberrant receptor activation, is associated with small-for-gestational-age babies and abnormal uterine spiral artery remodeling in humans. Our group studies a murine AGT gene titration transgenic (TG; 3-copies of the AGT gene) model, which has a 20% increase in AGT expression mimicking a common human AGT genetic variant (A[-6]G) associated with intrauterine growth restriction (IUGR) and spiral artery pathology. We hypothesized that aberrant maternal AGT expression impacts pregnancy-induced uterine spiral artery angiogenesis in this mouse model leading to IUGR. We controlled for fetal sex and fetal genotype (e.g., only 2-copy wild-type [WT] progeny from WT and TG dams were included). Uteroplacental samples from WT and TG dams from early (days 6.5 and 8.5), mid (d12.5), and late (d16.5) gestation were studied to assess uterine natural killer (uNK) cell phenotypes, decidual metrial triangle angiogenic factors, placental growth and capillary density, placental transcriptomics, and placental nutrient transport. Spiral artery architecture was evaluated at day 16.5 by contrast-perfused three-dimensional microcomputed tomography (3D microCT). Our results suggest that uteroplacental angiogenesis is significantly reduced in TG dams at day 16.5. Males from TG dams are associated with significantly reduced uteroplacental angiogenesis from early to late gestation compared with their female littermates and WT controls. Angiogenesis was not different between fetal sexes from WT dams. We conclude that male fetal sex compounds the pathologic impact of maternal genotype in this mouse model of growth restriction.


Assuntos
Retardo do Crescimento Fetal/fisiopatologia , Feto/fisiologia , Neovascularização Patológica , Placenta/irrigação sanguínea , Animais , Modelos Animais de Doenças , Feminino , Desenvolvimento Fetal/fisiologia , Retardo do Crescimento Fetal/imunologia , Retardo do Crescimento Fetal/patologia , Células Matadoras Naturais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/etiologia , Neovascularização Patológica/imunologia , Neovascularização Patológica/fisiopatologia , Placenta/imunologia , Placenta/patologia , Placentação/fisiologia , Gravidez , Caracteres Sexuais , Diferenciação Sexual/fisiologia , Útero/irrigação sanguínea , Útero/imunologia , Útero/patologia
9.
Hum Reprod ; 36(3): 571-586, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33600565

RESUMO

STUDY QUESTION: What is the physiological extent of vascular remodelling in and trophoblast plugging of the uterine circulation across the first half of pregnancy? SUMMARY ANSWER: All levels of the uterine vascular tree (arcuate, radial and spiral arteries (SAs)) dilate ∼2.6- to 4.3-fold between 6 and 20 weeks of gestation, with significant aggregates of trophoblasts persisting in the decidual and myometrial parts of SAs beyond the first trimester. WHAT IS KNOWN ALREADY: In early pregnancy, endovascular trophoblasts form 'plugs' in the SAs, transiently inhibiting blood flow to the placenta, whilst concurrently the uterine vasculature undergoes significant adaption to facilitate increased blood delivery to the placenta later in gestation. These processes are impaired in pregnancy disorders, but quantitative understanding of the anatomical changes even in normal pregnancy is poor. STUDY DESIGN, SIZE, DURATION: Serial sections of normal placentae in situ (n = 22) of 6.1-20.5 weeks of gestation from the Boyd collection and Dixon collection (University of Cambridge, UK) were digitalized using a slide scanner or Axio Imager.A1 microscope. PARTICIPANTS/MATERIALS, SETTING, METHODS: Spiral (n = 45), radial (n = 40) and arcuate (n = 39) arteries were manually segmented. Using custom-written scripts for Matlab® software, artery dimensions (Feret diameters; major axes; luminal/wall area) and endovascular trophoblast plug/aggregate (n = 24) porosities were calculated. Diameters of junctional zone SAs within the myometrium (n = 35) were acquired separately using a micrometre and light microscope. Decidual thickness and trophoblast plug depth was measured using ImageJ. MAIN RESULTS AND THE ROLE OF CHANCE: By all measures, radial and arcuate artery dimensions progressively increased from 6.1 to 20.5 weeks (P < 0.01). The greatest increase in SA calibre occurred after 12 weeks of gestation. Trophoblast aggregates were found to persist within decidual and myometrial parts of SA lumens beyond the first trimester, and up to 18.5 weeks of gestation, although those present in the second trimester did not appear to prevent the passage of red blood cells to the intervillous space. Trophoblasts forming these aggregates became more compact (decreased in porosity) over gestation, whilst channel size between cells increased (P = 0.01). Decidual thickness decreased linearly over gestation (P = 0.0003), meaning plugs occupied an increasing proportion of the decidua (P = 0.02). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Although serial sections were assessed, two-dimensional images cannot completely reflect the three-dimensional properties and connectivity of vessels and plugs/aggregates. Immersion-fixation of the specimens means that vessel size may be under-estimated. WIDER IMPLICATIONS OF THE FINDINGS: Uterine vascular remodelling and trophoblast plug dispersion is a progressive phenomenon that is not completed by the end of the first trimester. Our quantitative findings support the concept that radial arteries present a major site of resistance until mid-gestation. Their dimensional increase at 10-12 weeks of gestation may explain the rapid increase in blood flow to the placenta observed by others at ∼13 weeks. Measured properties of trophoblast plugs suggest that they will impact on the resistance, shear stress and nature of blood flow within the utero-placental vasculature until mid-gestation. The presence of channels within plugs will likely lead to high velocity flow streams and thus increase shear stress experienced by the trophoblasts forming the aggregates. Quantitative understanding of utero-placental vascular adaptation gained here will improve in silico modelling of utero-placental haemodynamics and provide new insights into pregnancy disorders, such as fetal growth restriction. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a Royal Society Te Aparangi Marsden Grant [18-UOA-135]. A.R.C. is supported by a Rutherford Discovery Fellowship [14-UOA-019]. The authors have no conflict of interest to declare.


Assuntos
Circulação Placentária , Trofoblastos , Decídua , Feminino , Humanos , Placenta , Gravidez , Primeiro Trimestre da Gravidez , Remodelação Vascular
10.
Am J Obstet Gynecol ; 223(4): 578.e1-578.e11, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32343954

RESUMO

BACKGROUND: Ureaplasma parvum infection is a prevalent cause of intrauterine infection associated with preterm birth, preterm premature rupture of membranes, fetal inflammatory response syndrome, and adverse postnatal sequelae. Elucidation of diagnostic and treatment strategies for infection-associated preterm labor may improve perinatal and long-term outcomes for these cases. OBJECTIVE: This study assessed the effect of intraamniotic Ureaplasma infection on fetal hemodynamic and cardiac function and the effect of maternal antibiotic treatment on these outcomes. STUDY DESIGN: Chronically catheterized pregnant rhesus monkeys were assigned to control (n=6), intraamniotic inoculation with Ureaplasma parvum (107 colony-forming units/mL, n=15), and intraamniotic infection plus azithromycin treatment (12.5 mg/kg twice a day intravenously, n=8) groups. At approximately 135 days' gestation (term=165 days), pulsed and color Doppler ultrasonography was used to obtain measurements of fetal hemodynamics (pulsatility index of umbilical artery, ductus venosus, descending aorta, ductus arteriosus, aortic isthmus, right pulmonary artery, middle cerebral artery and cerebroplacental ratio, and left and right ventricular cardiac outputs) and cardiac function (ratio of peak early vs late transmitral flow velocity [marker of ventricular function], Tei index [myocardial performance index]). These indices were stratified by amniotic fluid proinflammatory mediator levels and cardiac histology. RESULTS: Umbilical and fetal pulmonary artery vascular impedances were significantly increased in animals from the intraamniotic inoculation with Ureaplasma parvum group (P<.05). Azithromycin treatment restored values to control levels. Amniotic fluid prostaglandin F2 alpha levels were significantly higher in animals with abnormal umbilical artery pulsatility index (>1.1) than in those with normal blood flow (P<.05; Spearman ρ=0.6, P<.05). In the intraamniotic inoculation with Ureaplasma parvum group, left ventricular cardiac output was significantly decreased (P<.001), and more animals had abnormal right-to-left ventricular cardiac output ratios (defined as >1.6, P<.05). Amniotic fluid interleukin-6 concentrations were elevated in cases of abnormal right-to-left ventricular cardiac output ratios compared with those in normal cases (P<.05). CONCLUSION: Fetal hemodynamic alterations were associated with intraamniotic Ureaplasma infection and ameliorated after maternal antibiotic treatment. Doppler ultrasonographic measurements merit continuing investigation as a diagnostic method to identify fetal cardiovascular and hemodynamic compromise associated with intrauterine infection or inflammation and in the evaluation of therapeutic interventions or clinical management of preterm labor.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Corioamnionite/tratamento farmacológico , Coração Fetal/fisiopatologia , Hemodinâmica/fisiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Infecções por Ureaplasma/tratamento farmacológico , Administração Intravenosa , Âmnio , Líquido Amniótico/imunologia , Animais , Aorta/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Débito Cardíaco/fisiologia , Corioamnionite/imunologia , Corioamnionite/fisiopatologia , Modelos Animais de Doenças , Canal Arterial/diagnóstico por imagem , Ecocardiografia Doppler , Feminino , Injeções , Interleucina-6/imunologia , Macaca mulatta , Artéria Cerebral Média/diagnóstico por imagem , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/fisiopatologia , Artéria Pulmonar/diagnóstico por imagem , Fluxo Pulsátil , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Ureaplasma , Infecções por Ureaplasma/imunologia , Infecções por Ureaplasma/fisiopatologia
11.
Am J Physiol Cell Physiol ; 316(2): C264-C273, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30462538

RESUMO

Cancer-associated thrombosis is a common first presenting sign of malignancy and is currently the second leading cause of death in cancer patients after their malignancy. However, the molecular mechanisms underlying cancer-associated thrombosis remain undefined. In this study, we aimed to develop a better understanding of how cancer cells affect the coagulation cascade and platelet activation to induce a prothrombotic phenotype. Our results show that colon cancer cells trigger platelet activation in a manner dependent on cancer cell tissue factor (TF) expression, thrombin generation, activation of the protease-activated receptor 4 (PAR4) on platelets and consequent release of ADP and thromboxane A2. Platelet-colon cancer cell interactions potentiated the release of platelet-derived extracellular vesicles (EVs) rather than cancer cell-derived EVs. Our data show that single colon cancer cells were capable of recruiting and activating platelets and generating fibrin in plasma under shear flow. Finally, in a retrospective analysis of colon cancer patients, we found that the number of venous thromboembolism events was 4.5 times higher in colon cancer patients than in a control population. In conclusion, our data suggest that platelet-cancer cell interactions and perhaps platelet procoagulant EVs may contribute to the prothrombotic phenotype of colon cancer patients. Our work may provide rationale for targeting platelet-cancer cell interactions with PAR4 antagonists together with aspirin and/or ADP receptor antagonists as a potential intervention to limit cancer-associated thrombosis, balancing safety with efficacy.


Assuntos
Coagulação Sanguínea/fisiologia , Plaquetas/fisiologia , Neoplasias do Colo/sangue , Trombose/sangue , Plaquetas/patologia , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Estudos Transversais , Humanos , Estudos Retrospectivos , Trombose/patologia
12.
Platelets ; 30(1): 126-135, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30560697

RESUMO

Human platelets express two protease-activated receptors (PARs), PAR1 (F2R) and PAR4 (F2RL3), which are activated by a number of serine proteases that are generated during pathological events and cause platelet activation. Recent interest has focused on PAR4 as a therapeutic target, given PAR4 seems to promote experimental thrombosis and procoagulant microparticle formation, without a broadly apparent role in hemostasis. However, it is not yet known whether PAR4 activity plays a role in platelet-leukocyte interactions, which are thought to contribute to both thrombosis and acute or chronic thrombo-inflammatory processes. We sought to determine whether PAR4 activity contributes to granule secretion from activated platelets and platelet-leukocyte interactions. We performed in vitro and ex vivo studies of platelet granule release and platelet-leukocyte interactions in the presence of PAR4 agonists including PAR4 activating peptide, thrombin, cathepsin G, and plasmin in combination with small-molecule PAR4 antagonists. Activation of human platelets with thrombin, cathepsin G, or plasmin potentiated platelet dense granule secretion that was specifically impaired by PAR4 inhibitors. Platelet-leukocyte interactions and platelet P-selectin exposure the following stimulation with PAR4 agonists were also impaired by activated PAR4 inhibition in either a purified system or in whole blood. These results indicate PAR4-specific promotion of platelet granule release and platelet-leukocyte aggregate formation and suggest that pharmacological control of PAR4 activity could potentially attenuate platelet granule release or platelet-leukocyte interaction-mediated pathological processes.


Assuntos
Plaquetas/metabolismo , Comunicação Celular , Grânulos Citoplasmáticos/metabolismo , Leucócitos/metabolismo , Receptores de Trombina/metabolismo , Animais , Biomarcadores , Citometria de Fluxo , Humanos , Masculino , Papio , Ativação Plaquetária , Agregação Plaquetária
13.
Am J Physiol Regul Integr Comp Physiol ; 315(2): R354-R368, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29924631

RESUMO

Poor prenatal development, followed by rapid childhood growth, conveys greater cardiometabolic risk in later life. Microswine offspring exposed to perinatal maternal protein restriction [MPR; "low protein offspring" (LPO)] grow poorly in late-fetal/neonatal stages. After weaning to an ad libitum (AL) diet, LPO-AL exhibit accelerated growth and fat deposition rates with low adiponectin mRNA, despite low-normal body fat and small intra-abdominal adipocytes. We examined effects of caloric restriction (CR) on growth and metabolic status in LPO and normal protein offspring (NPO) randomized to AL or CR diets from weaning. CR transiently reduced growth in both LPO and NPO, delaying recovery in female LPO-CR. Over 7.5-12.5 weeks, linear growth rates in LPO-CR were slower than LPO-AL ( P < 0.001) but exceeded NPO-AL; body weight growth rates fell but were lower in LPO-CR versus NPO-CR. Linear acceleration ceased after 12 weeks. At 16 weeks, percent catch-up in LPO-CR was reduced versus LPO-AL ( P < 0.001). Plasma growth hormone was low in LPO ( P < 0.02). CR normalized fat deposition rate, yet adiponectin mRNA remained low in LPO-CR ( P < 0.001); plasma adiponectin was low in all LPO-AL and in female LPO-CR. Insulin sensitivity improved during CR. We conclude that in LPO: 1) CR delays onset of, but does not abolish, accelerated linear growth, despite low growth hormone; 2) CR yields stunting via delayed onset, plus a finite window for linear growth acceleration; 3) MPR lowers adiponectin mRNA independently of growth, adiposity, or adipocyte size; and 4) MPR reduces circulating adiponectin in LPO-AL and female LPO-CR, potentially enhancing cardiometabolic risk.


Assuntos
Adiponectina/sangue , Tecido Adiposo/fisiopatologia , Adiposidade , Restrição Calórica , Retardo do Crescimento Fetal/fisiopatologia , Estado Nutricional , Efeitos Tardios da Exposição Pré-Natal , Adiponectina/genética , Tecido Adiposo/metabolismo , Fatores Etários , Fenômenos Fisiológicos da Nutrição Animal , Animais , Glicemia/metabolismo , Modelos Animais de Doenças , Ingestão de Alimentos , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/genética , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Suínos , Porco Miniatura , Fatores de Tempo , Desmame , Aumento de Peso
14.
Gastrointest Endosc ; 84(2): 252-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26808815

RESUMO

BACKGROUND AND AIMS: EUS-guided FNA (EUS-FNA) is the primary method used to obtain pancreatic tissue for preoperative diagnosis. Accumulating evidence suggests diagnostic and prognostic information may be obtained by gene-expression profiling of these biopsy specimens. RNA sequencing (RNAseq) is a newer method of gene-expression profiling, but published data are scant on the use of this method on pancreas tissue obtained via EUS-FNA. The aim of this study was to determine whether RNAseq of EUS-FNA biopsy samples of undiagnosed pancreatic masses can reliably discriminate between benign and malignant tissue. METHODS: In this prospective study, consenting adults presented to 2 tertiary care hospitals for EUS of suspected pancreatic mass. Tissue was submitted for RNAseq. The results were compared with cytologic diagnosis, surgical pathology diagnosis, or benign clinical follow-up of at least 1 year. RESULTS: Forty-eight patients with solid pancreatic mass lesions were enrolled. Nine samples were excluded because of inadequate RNA and 3 because of final pathologic diagnosis of neuroendocrine tumor. Data from the first 13 patients were used to construct a linear classifier, and this was tested on the final 23 patients (15 malignant and 8 benign lesions). RNAseq of EUS-FNA biopsy samples distinguishes ductal adenocarcinoma from benign pancreatic solid masses with a sensitivity of .87 (range, .58-.98) and specificity of .75 (range, .35-.96). CONCLUSIONS: This proof-of-principle study suggests RNAseq of EUS-FNA samples can reliably detect adenocarcinoma and may provide a new method to evaluate more diagnostically challenging pancreatic lesions.


Assuntos
Adenocarcinoma/genética , Perfilação da Expressão Gênica/métodos , Neoplasias Pancreáticas/genética , Pancreatite/genética , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Pancreatite/diagnóstico , Pancreatite/patologia , Estudos Prospectivos , Análise de Sequência de RNA
15.
Am J Obstet Gynecol ; 214(5): 609.e1-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26627726

RESUMO

BACKGROUND: Provoked vestibulodynia is a poorly understood disease that affects 8-15% of women in their lifetime. There is significant inflammation and nerve growth in vestibular biopsies from affected women treated by vestibulectomy compared with matched female population controls without vestibulodynia. The triggers leading to this neurogenic inflammation are unknown, but they are likely multifactorial. OBJECTIVE: Our objective was to determine whether vestibulodynia is more common in close and distantly related female relatives of women diagnosed with the disease and those specifically treated by vestibulectomy. Excess familial clustering would support a potential genetic predisposition for vestibulodynia and warrant further studies to isolate risk alleles. STUDY DESIGN: Using population-based genealogy linked to University of Utah Hospital CPT coded data, we estimated the relative risk of vestibulectomy in female relatives of affected women. We also compared the average pairwise relatedness of cases to the expected relatedness of the population and identified high-disease-burden pedigrees. RESULTS: A total of 183 potential vestibulectomy probands were identified using CPT codes. The relative risk of vestibulectomy was elevated in first-degree (20 [6.6-47], P < .00001), second-degree (4.5 [0.5-16], P = .07), and third-degree female relatives (3.4 [1.2-8.8], P = .03). Seventy of these 183 CPT-based probands had available clinical history to confirm a diagnosis of moderate to severe vestibulodynia. Notably, this smaller group of confirmed probands (n = 70) revealed a similar familiality in first-degree (54 [17.5-126], P < .00001), second-degree (19.7 [2.4-71], P = .005), and third-degree relatives (12 [3.3-31], P = .0004), despite less statistical power for analysis. Overall, the average pairwise relatedness of affected women was significantly higher than expected (P < .001) and a number of high-disease-burden Utah families were identified. CONCLUSION: Our data suggest that vestibulodynia treated by vestibulectomy has a genetic predisposition. Future studies will identify candidate genes by linkage analysis in affected families and sequencing of distantly related probands.


Assuntos
Predisposição Genética para Doença , Vulvodinia/genética , Vulvodinia/cirurgia , Comorbidade , Constipação Intestinal/epidemiologia , Current Procedural Terminology , Cistite Intersticial/epidemiologia , Bases de Dados Factuais , Feminino , Humanos , Mialgia/epidemiologia , Miosite/epidemiologia , Linhagem , Probabilidade , Utah/epidemiologia , Vulvodinia/epidemiologia
16.
Am J Obstet Gynecol ; 214(3): 369.e1-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26928151

RESUMO

BACKGROUND: The uteroplacental vascular supply is a critical determinant of placental function and fetal growth. Current methods for the in vivo assessment of placental blood flow are limited. OBJECTIVE: We demonstrate the feasibility of the use of contrast-enhanced ultrasound imaging to visualize and quantify perfusion kinetics in the intervillous space of the primate placenta. STUDY DESIGN: Pregnant Japanese macaques were studied at mid second trimester and in the early third trimester. Markers of injury were assessed in placenta samples from animals with or without contrast-enhanced ultrasound exposure (n = 6/group). Human subjects were recruited immediately before scheduled first-trimester pregnancy termination. All studies were performed with maternal intravenous infusion of lipid-shelled octofluoropropane microbubbles with image acquisition with a multipulse contrast-specific algorithm with destruction-replenishment analysis of signal intensity for assessment of perfusion. RESULTS: In macaques, the rate of perfusion in the intervillous space was increased with advancing gestation. No evidence of microvascular hemorrhage or acute inflammation was found in placental villous tissue and expression levels of caspase-3, nitrotyrosine and heat shock protein 70 as markers of apoptosis, nitrative, and oxidative stress, respectively, were unchanged by contrast-enhanced ultrasound exposure. In humans, placental perfusion was visualized at 11 weeks gestation, and preliminary data reveal regional differences in intervillous space perfusion within an individual placenta. By electron microscopy, we demonstrate no evidence of ultrastructure damage to the microvilli on the syncytiotrophoblast after first-trimester ultrasound studies. CONCLUSIONS: Use of contrast-enhanced ultrasound did not result in placental structural damage and was able to identify intervillous space perfusion rate differences within a placenta. Contrast-enhanced ultrasound imaging may offer a safe clinical tool for the identification of pregnancies that are at risk for vascular insufficiency; early recognition may facilitate intervention and improved pregnancy outcomes.


Assuntos
Vilosidades Coriônicas/irrigação sanguínea , Vilosidades Coriônicas/diagnóstico por imagem , Meios de Contraste , Microbolhas , Circulação Placentária , Algoritmos , Animais , Caspase 3/metabolismo , Vilosidades Coriônicas/ultraestrutura , Meios de Contraste/efeitos adversos , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Cinética , Macaca , Microbolhas/efeitos adversos , Gravidez , Primeiro Trimestre da Gravidez/fisiologia , Segundo Trimestre da Gravidez/fisiologia , Terceiro Trimestre da Gravidez/fisiologia , Processamento de Sinais Assistido por Computador , Trofoblastos/ultraestrutura , Tirosina/análogos & derivados , Tirosina/metabolismo , Ultrassonografia
17.
Am J Perinatol ; 33(3): 258-66, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26731184

RESUMO

Preterm birth is a multifactorial syndrome with a variety of risk factors and long-term health consequences for the child. Placental pathology provides important diagnostic information to ascertain the cause of preterm birth. For example, intra-amniotic infection is one risk factor, but accumulating evidence based on placental pathology, amniotic fluid cultures, and polymerase chain reaction studies suggests infection may be a less common cause of preterm birth than previously suspected, especially after 32 weeks' gestation. Instead, many cases of spontaneous preterm labor leading to preterm birth appear to be caused by placental insufficiency, similar to preeclampsia and fetal growth restriction. Other causes of preterm birth, including retroplacental abruption, chronic villitis, and twin gestations, also have specific placental pathology related to placental insufficiency. New insights into the underlying mechanisms regulating uteroplacental blood flow and the impact of placental malperfusion on placental health may lead to improved early gestation diagnostic testing and a revolution in preventative care for both the mother and her child.


Assuntos
Descolamento Prematuro da Placenta/patologia , Trabalho de Parto Prematuro/etiologia , Placenta/patologia , Insuficiência Placentária/patologia , Nascimento Prematuro/etiologia , Feminino , Retardo do Crescimento Fetal/etiologia , Idade Gestacional , Humanos , Recém-Nascido , Pré-Eclâmpsia/etiologia , Gravidez , Gravidez de Gêmeos
18.
J Low Genit Tract Dis ; 20(3): 201-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26855146

RESUMO

OBJECTIVE: Loop electrosurgical excision procedures (LEEPs) are negative for high-grade cervical intraepithelial neoplasia (CIN 2+) after a hematoxylin and eosin-based CIN 2+ colposcopic biopsy diagnosis in 14% to 24% of cases. This may be due to diagnostic errors or biopsy-related regression of the dysplasia. Because p16 immunohistochemical staining of cervical biopsies improves diagnostic accuracy, we hypothesized that p16-based cervical biopsy diagnoses may reduce the frequency of negative LEEPs. MATERIALS AND METHODS: We performed a retrospective cross-sectional study of all cervical LEEPs completed at our institution from 2002 to 2012. We recorded patient age, sexual history, smoking history, pathologic diagnoses (including whether the diagnosis was p16 based), the number of days from biopsy to follow-up LEEP, and clinical follow-up. This yielded 593 study subjects meeting inclusion criteria of CIN 2+ colposcopic diagnoses with follow-up LEEP and 2 years of clinical follow-up. Colposcopic biopsies and follow-up LEEPs were reviewed and p16 immunostaining was performed on all samples to provide criterion standard results. Data were analyzed by χ and regression modeling. RESULTS: Our practice employed p16 to aid cervical biopsy diagnoses by 2006. The frequency of negative LEEPs before 2006 was 12 (10%) of 126. The frequency dropped during the p16 era (2006-2012) to 23 (5%) of 467. Overall, we observed an inverse relationship between the frequency of p16 employment and the frequency of negative LEEP outcomes (R = 0.71; p < .001), independent of potential covariates. CONCLUSIONS: Our data suggest that more accurate p16-based diagnoses may reduce the frequency of unnecessary LEEPs.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/análise , Eletrocirurgia/estatística & dados numéricos , Imuno-Histoquímica/métodos , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/cirurgia , Adulto , Biomarcadores Tumorais/análise , Biópsia , Estudos Transversais , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/estatística & dados numéricos , Feminino , Humanos , Imuno-Histoquímica/estatística & dados numéricos , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Am J Obstet Gynecol ; 212(3): 370.e1-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25725660

RESUMO

OBJECTIVE: We previously demonstrated that prenatal nicotine exposure decreases neonatal pulmonary function in nonhuman primates, and maternal vitamin C supplementation attenuates these deleterious effects. However, the effect of nicotine on placental perfusion and development is not fully understood. This study utilizes noninvasive imaging techniques and histological analysis in a nonhuman primate model to test the hypothesis that prenatal nicotine exposure adversely effects placental hemodynamics and development but is ameliorated by vitamin C. STUDY DESIGN: Time-mated macaques (n = 27) were divided into 4 treatment groups: control (n = 5), nicotine only (n = 4), vitamin C only (n = 9), and nicotine plus vitamin C (n = 9). Nicotine animals received 2 mg/kg per day of nicotine bitartrate (approximately 0.7 mg/kg per day free nicotine levels in pregnant human smokers) from days 26 to 160 (term, 168 days). Vitamin C groups received ascorbic acid at 50, 100, or 250 mg/kg per day with or without nicotine. All underwent placental dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) at 135-140 days and Doppler ultrasound at 155 days to measure uterine artery and umbilical vein velocimetry and diameter to calculate uterine artery volume blood flow and placental volume blood flow. Animals were delivered by cesarean delivery at 160 days. A novel DCE-MRI protocol was utilized to calculate placental perfusion from maternal spiral arteries. Placental tissue was processed for histopathology. RESULTS: Placental volume blood flow was significantly reduced in nicotine-only animals compared with controls and nicotine plus vitamin C groups (P = .03). Maternal placental blood flow was not different between experimental groups by DCE-MRI, ranging from 0.75 to 1.94 mL/mL per minute (P = .93). Placental histology showed increased numbers of villous cytotrophoblast cell islands (P < .05) and increased syncytiotrophoblast sprouting (P < .001) in nicotine-only animals, which was mitigated by vitamin C. CONCLUSION: Prenatal nicotine exposure significantly decreased fetal blood supply via reduced placental volume blood flow, which corresponded with placental histological findings previously associated with cigarette smoking. Vitamin C supplementation mitigated the harmful effects of prenatal nicotine exposure on placental hemodynamics and development, suggesting that its use may limit some of the adverse effects associated with smoking during pregnancy.


Assuntos
Ácido Ascórbico/farmacologia , Estimulantes Ganglionares/efeitos adversos , Exposição Materna/efeitos adversos , Nicotina/efeitos adversos , Placenta/efeitos dos fármacos , Circulação Placentária/efeitos dos fármacos , Vitaminas/farmacologia , Animais , Ácido Ascórbico/administração & dosagem , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Estimulantes Ganglionares/administração & dosagem , Macaca , Imageamento por Ressonância Magnética , Nicotina/administração & dosagem , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Placenta/patologia , Gravidez , Distribuição Aleatória , Ultrassonografia Doppler em Cores , Vitaminas/administração & dosagem
20.
J Low Genit Tract Dis ; 19(4): 345-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26360236

RESUMO

OBJECTIVE: High-risk human papillomavirus (hrHPV) infection is more likely to persist and cause cervical cancer in immunosuppressed women. Atopic dermatitis, which is known to affect cell-mediated immunity and skin barrier function, is associated with recalcitrant warts; therefore, we hypothesized that women with atopic dermatitis may be more likely to be positive for hrHPV infection and progress to high-grade cervical dysplasia. MATERIALS AND METHODS: A retrospective case-control study of 1,160 women who were either positive or negative for hrHPV in their index cervical cytology. Patient age, race, history of atopic dermatitis, allergic rhinitis, smoking, body mass index, socioeconomic status, marital status, hormone contraceptive use, and 2-year clinical outcomes (follow-up hrHPV testing and cervical biopsy results) were recorded. All cases with atopic dermatitis (n = 74) were confirmed by a dermatologist. Analyses were restricted to females with documented clinical follow-up, which yielded 577 hrHPV-positive and 583 hrHPV-negative cases for comparison. Associations were examined by t test, χ test, and multivariate logistic regression. RESULTS: Atopic dermatitis was more common in the hrHPV-positive cases (48/577, 8.3%) compared with HPV-negative controls (26/583, 4.5%, p = .007). Multivariate logistic regression analysis revealed an adjusted odds ratio of 3.75 (95% CI = 1.3-10.9, p = .02) after controlling for significant covariates, such as age and marital status. Smoking was not associated with hrHPV infection, persistence, or high-grade cervical dysplasia in these cases. CONCLUSIONS: Atopic dermatitis is associated with cervical hrHPV infection in adult women.


Assuntos
Dermatite Atópica/complicações , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Cervicite Uterina/epidemiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Estudos Retrospectivos , Medição de Risco , Cervicite Uterina/complicações
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