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1.
Regen Ther ; 27: 207-217, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38576851

RESUMO

Background: Perinatal inflammation increases the risk for bronchopulmonary dysplasia in preterm neonates, but the underlying pathophysiological mechanisms remain largely unknown. Given their anti-inflammatory and regenerative capacity, multipotent adult progenitor cells (MAPC) are a promising cell-based therapy to prevent and/or treat the negative pulmonary consequences of perinatal inflammation in the preterm neonate. Therefore, the pathophysiology underlying adverse preterm lung outcomes following perinatal inflammation and pulmonary benefits of MAPC treatment at the interface of prenatal inflammatory and postnatal ventilation exposures were elucidated. Methods: Instrumented ovine fetuses were exposed to intra-amniotic lipopolysaccharide (LPS 5 mg) at 125 days gestation to induce adverse systemic and peripheral organ outcomes. MAPC (10 × 106 cells) or saline were administered intravenously two days post LPS exposure. Fetuses were delivered preterm five days post MAPC treatment and either killed humanely immediately or mechanically ventilated for 72 h. Results: Antenatal LPS exposure resulted in inflammation and decreased alveolar maturation in the preterm lung. Additionally, LPS-exposed ventilated lambs showed continued pulmonary inflammation and cell junction loss accompanied by pulmonary edema, ultimately resulting in higher oxygen demand. MAPC therapy modulated lung inflammation, prevented loss of epithelial and endothelial barriers and improved lung maturation in utero. These MAPC-driven improvements remained evident postnatally, and prevented concomitant pulmonary edema and functional loss. Conclusion: In conclusion, prenatal inflammation sensitizes the underdeveloped preterm lung to subsequent postnatal inflammation, resulting in injury, disturbed development and functional impairment. MAPC therapy partially prevents these changes and is therefore a promising approach for preterm infants to prevent adverse pulmonary outcomes.

2.
Cancers (Basel) ; 16(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38339249

RESUMO

Breast cancer is the most prevalent malignancy among women worldwide, and the increasing number of survivors is due to advances in early diagnosis and treatment efficacy. Consequently, the risk of developing contralateral breast cancer (CBC) among these survivors has become a concern. While surgical intervention with lumpectomy is a widely used primary approach for breast cancer, post-operative breast asymmetry is a potential concern. Many women opt for symmetrizing reduction procedures to improve aesthetic outcomes and quality of life. However, despite careful radiological screening, there is a chance of accidentally finding CBC. To address this, tissue excised during symmetrizing surgery is examined pathologically. In some cases, CBC or in situ lesions have been incidentally discovered in these specimens, prompting a need for a more thorough examination. Resection in pieces and the absence of surgical marking and pathological inking of the margin have made it challenging to precisely identify tumor location and assess tumor size and margin status, hampering adjuvant treatment decisions. A new protocol introduced in July 2022 aims to enhance the precision of CBC diagnosis, allowing for tailored treatment plans, including re-excision, systemic adjuvant therapy, or radiation therapy.

3.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834652

RESUMO

Pre-eclampsia is a severe placenta-related complication of pregnancy with limited early diagnostic and therapeutic options. Aetiological knowledge is controversial, and there is no universal consensus on what constitutes the early and late phenotypes of pre-eclampsia. Phenotyping of native placental three-dimensional (3D) morphology offers a novel approach to improve our understanding of the structural placental abnormalities in pre-eclampsia. Healthy and pre-eclamptic placental tissues were imaged with multiphoton microscopy (MPM). Imaging based on inherent signal (collagen, and cytoplasm) and fluorescent staining (nuclei, and blood vessels) enabled the visualization of placental villous tissue with subcellular resolution. Images were analysed with a combination of open source (FIJI, VMTK, Stardist, MATLAB, DBSCAN), and commercially (MATLAB) available software. Trophoblast organization, 3D-villous tree structure, syncytial knots, fibrosis, and 3D-vascular networks were identified as quantifiable imaging targets. Preliminary data indicate increased syncytial knot density with characteristic elongated shape, higher occurrence of paddle-like villous sprouts, abnormal villous volume-to-surface ratio, and decreased vascular density in pre-eclampsia compared to control placentas. The preliminary data presented indicate the potential of quantifying 3D microscopic images for identifying different morphological features and phenotyping pre-eclampsia in placental villous tissue.


Assuntos
Placenta , Pré-Eclâmpsia , Humanos , Gravidez , Feminino , Placenta/irrigação sanguínea , Imageamento Tridimensional , Trofoblastos , Fenótipo
4.
Front Med (Lausanne) ; 8: 614239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33693012

RESUMO

Perinatal inflammatory stress is strongly associated with adverse pulmonary outcomes after preterm birth. Antenatal infections are an essential perinatal stress factor and contribute to preterm delivery, induction of lung inflammation and injury, pre-disposing preterm infants to bronchopulmonary dysplasia. Considering the polymicrobial nature of antenatal infection, which was reported to result in diverse effects and outcomes in preterm lungs, the aim was to examine the consequences of sequential inflammatory stimuli on endogenous epithelial stem/progenitor cells and vascular maturation, which are crucial drivers of lung development. Therefore, a translational ovine model of antenatal infection/inflammation with consecutive exposures to chronic and acute stimuli was used. Ovine fetuses were exposed intra-amniotically to Ureaplasma parvum 42 days (chronic stimulus) and/or to lipopolysaccharide 2 or 7 days (acute stimulus) prior to preterm delivery at 125 days of gestation. Pulmonary inflammation, endogenous epithelial stem cell populations, vascular modulators and morphology were investigated in preterm lungs. Pre-exposure to UP attenuated neutrophil infiltration in 7d LPS-exposed lungs and prevented reduction of SOX-9 expression and increased SP-B expression, which could indicate protective responses induced by re-exposure. Sequential exposures did not markedly impact stem/progenitors of the proximal airways (P63+ basal cells) compared to single exposure to LPS. In contrast, the alveolar size was increased solely in the UP+7d LPS group. In line, the most pronounced reduction of AEC2 and proliferating cells (Ki67+) was detected in these sequentially UP + 7d LPS-exposed lambs. A similar sensitization effect of UP pre-exposure was reflected by the vessel density and expression of vascular markers VEGFR-2 and Ang-1 that were significantly reduced after UP exposure prior to 2d LPS, when compared to UP and LPS exposure alone. Strikingly, while morphological changes of alveoli and vessels were seen after sequential microbial exposure, improved lung function was observed in UP, 7d LPS, and UP+7d LPS-exposed lambs. In conclusion, although sequential exposures did not markedly further impact epithelial stem/progenitor cell populations, re-exposure to an inflammatory stimulus resulted in disturbed alveolarization and abnormal pulmonary vascular development. Whether these negative effects on lung development can be rescued by the potentially protective responses observed, should be examined at later time points.

5.
Pediatr Res ; 90(3): 549-558, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33070161

RESUMO

BACKGROUND: Chorioamnionitis, an intrauterine infection of the placenta and fetal membranes, is a common risk factor for adverse pulmonary outcomes in premature infants including BPD, which is characterized by an arrest in alveolar development. As endogenous epithelial stem/progenitor cells are crucial for organogenesis and tissue repair, we examined whether intrauterine inflammation negatively affects these essential progenitor pools. METHODS: In an ovine chorioamnionitis model, fetuses were intra-amniotically exposed to LPS, 2d or 7d (acute inflammation) before preterm delivery at 125d of gestation, or to intra-amniotic Ureaplasma parvum for 42d (chronic inflammation). Lung function, pulmonary endogenous epithelial stem/progenitor pools, and downstream functional markers were studied. RESULTS: Lung function was improved in the 7d LPS and 42d Ureaplasma groups. However, intrauterine inflammation caused a loss of P63+ basal cells in proximal airways and reduced SOX-9 expression and TTF-1+ Club cells in distal airways. Attenuated type-2 cell numbers were associated with lower proliferation and reduced type-1 cell marker Aqp5 expression, indicative for impaired progenitor function. Chronic Ureaplasma infection only affected distal airways, whereas acute inflammation affected stem/progenitor populations throughout the lungs. CONCLUSIONS: Acute and chronic prenatal inflammation improve lung function at the expense of stem/progenitor alterations that potentially disrupt normal lung development, thereby predisposing to adverse postnatal outcomes. IMPACT: In this study, prenatal inflammation improved lung function at the expense of stem/progenitor alterations that potentially disrupt normal lung development, thereby predisposing to adverse postnatal outcomes. Importantly, we demonstrate that these essential alterations can already be initiated before birth. So far, stem/progenitor dysfunction has only been shown postnatally. This study indicates that clinical protocols to target the consequences of perinatal inflammatory stress for the immature lungs should be initiated as early as possible and ideally in utero. Within this context, our data suggest that interventions, which promote function or repair of endogenous stem cells in the lungs, hold great promise.


Assuntos
Corioamnionite/patologia , Pulmão/patologia , Células-Tronco/patologia , Animais , Células Epiteliais/patologia , Feminino , Gravidez , Nascimento Prematuro , Ovinos
6.
Gynecol Obstet Invest ; 84(6): 616-622, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31357192

RESUMO

BACKGROUND/AIMS: Placental syndromes (PS) refer to pregnancy complications that include gestational hypertension, (pre)eclampsia, HELLP syndrome, and/or placental insufficiency-induced fetal growth restriction. These disorders are characterized by increased oxidative stress. This study aims to test the hypothesis that the abnormal hemodynamic adaptation to pregnancy, typical for early PS pregnancy, is accompanied by abnormal maternal levels of antioxidants relative to those in normal pregnancy. METHODS: Before, and at 12, 16, and 20 weeks pregnancy, we measured trolox equivalent antioxidant capacity (TEAC), uric acid (UA), and TEACC (TEAC corrected for UA) in maternal serum of former PS patients, who either developed recurrent PS (rPS; n = 16) or had a normal next pregnancy (non-rPS; n = 23). Concomitantly, we also measured various hemodynamic variables. RESULTS: rPS differed from non-rPS by higher TEACC levels before pregnancy (178 vs. 152 µM; p = 0.02) and at 20 weeks pregnancy (180 vs. 160 µM; p = 0.04). Only non-rPS responded to pregnancy by significant rises in hemodynamic measures. CONCLUSION: These data indicate that rPS pregnancies are preceded by an increase in antioxidant capacity, presumably induced by subclinical vascular injury and low-grade chronic inflammation.


Assuntos
Antioxidantes/análise , Hemodinâmica/fisiologia , Doenças Placentárias/sangue , Complicações na Gravidez/sangue , Adulto , Feminino , Retardo do Crescimento Fetal/sangue , Idade Gestacional , Síndrome HELLP/sangue , Humanos , Hipertensão Induzida pela Gravidez/sangue , Estresse Oxidativo , Placenta/fisiopatologia , Insuficiência Placentária/sangue , Pré-Eclâmpsia/sangue , Gravidez , Recidiva , Síndrome
7.
Gynecol Obstet Invest ; 82(4): 355-360, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27644043

RESUMO

BACKGROUND/AIM: Placental syndromes (PS) are characterized by endothelial dysfunction complicating placental dysfunction. Possible markers for endothelial dysfunction and amount of trophoblast are fibronectin and plasminogen activator inhibitor-2 (PAI-2), respectively. We aimed (1) to determine whether in women with recurrent PS (rPS), this complication is preceded by deviating fibronectin- and PAI-2-levels, and (2) whether this is dependent on pre-pregnant plasma volume (PV). METHODS: In 36 former patients, we determined fibronectin- and PAI-2-levels in blood-samples collected preconceptionally and at 12-16 weeks in their next pregnancy. Differences were analyzed between pregnancies with rPS (n = 12) and without rPS (non-rPS, n = 24) using linear mixed models, with subanalyses based on pre-pregnant normal or subnormal PV. RESULTS: We observed higher fibronectin-levels at 12-16 weeks (p < 0.05 and p < 0.01, respectively) and lower PAI-2-levels at 16 weeks (p < 0.01) in the rPS subgroup, the intergroup differences being larger in women with subnormal PV. CONCLUSION: We showed that former PS patients who developed rPS have raised fibronectin- and reduced PAI-2-levels already in early/mid pregnancy. These deviations are even more prominent in women with subnormal pre-pregnant PV, supporting development of a 2-step screening program for former patients to identify the high-risk subgroup of women who may benefit from closer surveillance.


Assuntos
Fibronectinas/sangue , Doenças Placentárias/etiologia , Inibidor 2 de Ativador de Plasminogênio/sangue , Trimestres da Gravidez/sangue , Adulto , Biomarcadores , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Gravidez , Recidiva , Estudos Retrospectivos , Síndrome
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