Intra-amniotic infection and inflammation are major causes of preterm birth (PTB). However, intraamniotic inflammation is often detected in the absence of infection. This may partly be due to the culturing methods employed in hospital laboratories, which are unable to detect the uncultivated species. In this study, intra-amniotic microbial infections associated with PTB were examined by both culture and 16S rRNA-based culture-independent methods and were corroborated by the presence of intra-amniotic inflammation. Amniotic fluid (AF) specimens from 46 pregnancies complicated by PTB and 16 asymptomatic women were analyzed. No bacterial DNA was amplified in AF collected from the asymptomatic women. Among the 46 samples associated with PTB, bacterial DNA was amplified from all (16/16) of the culture-positive samples and 17% (5/30) of the culture-negative samples. In the culture-positive group, additional species were detected in more than half (9/16) of the cases by PCR and clone analysis. Altogether, approximately two-thirds of the species detected by the culture-independent methods were not isolated by culture. They included both uncultivated and difficultto-cultivate species, such as Fusobacterium nucleatum, Leptotrichia (Sneathia) spp., a Bergeyella sp., a Peptostreptococcus sp., Bacteroides spp., and a species of the order Clostridiales. To examine intra-amniotic inflammation, an AF proteomic fingerprint (mass-restricted score) was determined by surface-enhanced laser desorption ionization-time-of-flight mass spectrometry. Inflammation was detected in all five samples which were culture negative but PCR positive. Women who were PCR positive more often had elevated interleukin-6 levels in their AF, histological chorioamnionitis, and funisitis and delivered neonates with early-onset neonatal sepsis. Previously unrecognized, uncultivated, or difficult-to-cultivate species may play a key role in the initiation of PTB.
Preeclampsia is a pregnancy-specific disorder of unknown etiology and a leading contributor to maternal and perinatal morbidity and mortality worldwide. Because there is no cure other than delivery, preeclampsia is the leading cause of iatrogenic preterm birth. We show that preeclampsia shares pathophysiologic features with recognized protein misfolding disorders. These features include urine congophilia (affinity for the amyloidophilic dye Congo red), affinity for conformational state-dependent antibodies, and dysregulation of prototype proteolytic enzymes involved in amyloid precursor protein (APP) processing. Assessment of global protein misfolding load in pregnancy based on urine congophilia (Congo red dot test) carries diagnostic and prognostic potential for preeclampsia. We used conformational state-dependent antibodies to demonstrate the presence of generic supramolecular assemblies (prefibrillar oligomers and annular protofibrils), which vary in quantitative and qualitative representation with preeclampsia severity. In the first attempt to characterize the preeclampsia misfoldome, we report that the urine congophilic material includes proteoforms of ceruloplasmin, immunoglobulin free light chains, SERPINA1, albumin, interferon-inducible protein 6-16, and Alzheimer's β-amyloid. The human placenta abundantly expresses APP along with prototype APP-processing enzymes, of which the α-secretase ADAM10, the β-secretases BACE1 and BACE2, and the γ-secretase presenilin-1 were all up-regulated in preeclampsia. The presence of β-amyloid aggregates in placentas of women with preeclampsia and fetal growth restriction further supports the notion that this condition should join the growing list of protein conformational disorders. If these aggregates play a pathophysiologic role, our findings may lead to treatment for preeclampsia.
H ydrogen sulfide (H 2 S), a gaseous signaling molecule, promotes vasodilatation 1 and stimulates angiogenesis in the vasculature.2 H 2 S has anti-inflammatory properties 3 and is also cytoprotective against cellular damage induced by lethal hypoxia or reperfusion injury. 4,5 Cystathionine γ-lyase (CSE) is the principal enzyme responsible for the endogenous production of H 2 S.6 Chronic administration of the CSE inhibitor DL-propargylglycine (PAG) leads to elevated blood pressure and vascular remodeling in the rat, 7 and both CSE and H 2 S levels are reduced in pulmonary hypertensive rats. 8Mice genetically deficient in CSE develop age-dependent hypertension, severe hyperhomocysteinemia, and endothelial dysfunction. 9 Clearly, H 2 S has multiple roles in health and disease, 10,11 but its role in pregnancy-induced hypertension is unknown. Editorial see p 2472 Clinical Perspective on p 2522Preeclampsia is a hypertensive syndrome that affects 4% to 7% of all pregnancies and is a major contributor to maternal and fetal morbidity and mortality worldwide. 12 The exact etiology of preeclampsia is unknown; abnormal placentation 13,14 and imbalance in angiogenic factors 15,16 have been implicated in preeclampsia pathogenesis. Importantly, circulating levels of soluble fms-like tyrosine kinase-1 (sFlt-1), the endogenous inhibitor of vascular endothelial growth factor and placental Background-The exact etiology of preeclampsia is unknown, but there is growing evidence of an imbalance in angiogenic growth factors and abnormal placentation. Hydrogen sulfide (H 2 S), a gaseous messenger produced mainly by cystathionine γ-lyase (CSE), is a proangiogenic vasodilator. We hypothesized that a reduction in CSE activity may alter the angiogenic balance in pregnancy and induce abnormal placentation and maternal hypertension. Methods and Results-Plasma levels of H 2 S were significantly decreased in women with preeclampsia (P<0.01), which was associated with reduced placental CSE expression as determined by real-time polymerase chain reaction and immunohistochemistry. Inhibition of CSE activity by DL-propargylglycine reduced placental growth factorproduction from first-trimester (8-12 weeks gestation) human placental explants and inhibited trophoblast invasion in vitro. Knockdown of CSE in human umbilical vein endothelial cells by small-interfering RNA increased the release of soluble fms-like tyrosine kinase-1 and soluble endoglin, as assessed by enzyme-linked immunosorbent assay, whereas adenoviral-mediated CSE overexpression in human umbilical vein endothelial cells inhibited their release. Administration of DL-propargylglycine to pregnant mice induced hypertension and liver damage, promoted abnormal labyrinth vascularization in the placenta, and decreased fetal growth. Finally, a slow-releasing H 2 S-generating compound, GYY4137, inhibited circulating soluble fms-like tyrosine kinase-1 and soluble endoglin levels and restored fetal growth in mice that was compromised by DL-propargylglycine treatment, demonstrating that the effect ...
a Background Intra-amniotic inflammation is associated with poor neonatal outcome independent of prematurity. We applied proteomic technology (SELDI: surface-enhanced laser desorption ionisation) to identify the proteomic profile of intra-amniotic inflammation. Design One hundred and four samples of amniotic fluid were analysed. In stage 1, samples from patients with symptoms of preterm labour and known outcomes were tested to identify the characteristic profile for inflammation. We extracted the profile using a novel, stepwise logical approach comparing SELDI tracings from patients who delivered preterm and had intra-amniotic inflammation in response to infection to the tracings of patients who had symptoms of preterm labour but delivered at term. In stage 2, we applied the algorithm to samples from pregnancies whose outcomes were unknown to the investigators. Setting North-American university in collaboration with Ciphergen field demonstration laboratory.Sample One hundred and four samples of human amniotic fluid from transabdominal amniocentesis.Methods SELDI (surface-enhanced laser desorption ionisation) and Mass Restricted analysis, a novel algorithm for extraction of clinical and biological relevant biomarkers from proteomic SELDI tracings. Main outcome measure Presence of intra-amniotic inflammation and/or infection leading to preterm birth.Results Patients with intra-amniotic inflammation that deliver preterm have a distinctive amniotic fluid proteomic profile of three or four of the following proteins: neutrophil defensins-1 and -2, and calgranulins A and C. Based on the presence or absence of these biomarkers, we devised the mass restricted (MR) score ranging from 0 (all biomarker peaks absent) to 4 (all biomarker peaks present). In stage 1, MR score > 2 had 92.9% sensitivity (95% CI 76.5 -98.9) and 91.8% specificity (95% CI 80.4 -97.7) for detection of intraamniotic inflammation. In blind testing (stage 2), MR score > 2 provided 100% specificity and sensitivity (95% CI 100-100). A MR score > 2 was associated with imminent preterm delivery. Conclusion Proteomic analysis of amniotic fluid reveals the presence of biomarkers characteristic of intrauterine inflammation. This methodology may identify the subgroup of patients that might benefit most from interventions to prevent fetal damage in utero.
Objective An acquired uterine arteriovenous malformation (AVM) is a rare cause of vaginal bleeding and, although hysterectomy is the definitive therapy, transcatheter embolization (TCE) provides an alternative treatment option. This systematic review presents the indications, technique, and outcomes for transcatheter treatment of the acquired uterine AVMs. Study Design Literature databases were searched from 2003 to 2013 for eligible clinical studies, including the patient characteristics, procedural indication, results, complications, as well as descriptions on laterality and embolic agents utilized. Results A total of 40 studies were included comprising of 54 patients (average age of 33.4 years). TCE had a primary success rate with symptomatic control of 61% (31 patients) and secondary success rate of 91% after repeated embolization. When combined with medical therapy, symptom resolution was noted in 48 (85%) patients without more invasive surgical procedures. Conclusion Low-level evidence supports the role of TCE, including in the event of persistent bleeding following initial embolization, for the treatment of acquired uterine AVMs. The variety of embolic agents and laterality of approach delineate the importance of refining procedural protocols in the treatment of the acquired uterine AVM. Condensation A review on the management of patients with acquired uterine AVMs.
BackgroundProteomic analysis of amniotic fluid shows the presence of biomarkers characteristic of intrauterine inflammation. We sought to validate prospectively the clinical utility of one such proteomic profile, the Mass Restricted (MR) score.Methods and FindingsWe enrolled 169 consecutive women with singleton pregnancies admitted with preterm labor or preterm premature rupture of membranes. All women had a clinically indicated amniocentesis to rule out intra-amniotic infection. A proteomic fingerprint (MR score) was generated from fresh samples of amniotic fluid using surface-enhanced laser desorption ionization (SELDI) mass spectrometry. Presence or absence of the biomarkers of the MR score was interpreted in relationship to the amniocentesis-to-delivery interval, placental inflammation, and early-onset neonatal sepsis for all neonates admitted to the Newborn Special Care Unit (n = 104). Women with “severe” amniotic fluid inflammation (MR score of 3 or 4) had shorter amniocentesis-to-delivery intervals than women with “no” (MR score of 0) inflammation or even “minimal” (MR score of 1 or 2) inflammation (median [range] MR 3–4: 0.4 d [0.0–49.6 d] versus MR 1–2: 3.8 d [0.0–151.2 d] versus MR 0: 17.0 d [0.1–94.3 d], p < 0.001). Nonetheless, a “minimal” degree of inflammation was also associated with preterm birth regardless of membrane status. There was a significant association between the MR score and severity of histological chorioamnionitis (r = 0.599, p < 0.001). Furthermore, neonatal hematological indices and early-onset sepsis significantly correlated with the MR score even after adjusting for gestational age at birth (OR for MR 3–4: 3.3 [95% CI, 1.1 to 9.2], p = 0.03). When compared with other laboratory tests routinely used to diagnose amniotic fluid inflammation and infection, the MR score had the highest accuracy to detect inflammation (white blood cell count > 100 cells/mm3), whereas the combination of Gram stain and MR score was best for rapid prediction of intra-amniotic infection (positive amniotic fluid culture).ConclusionsHigh MR scores are associated with preterm delivery, histological chorioamnionitis, and early-onset neonatal sepsis. In this study, proteomic analysis of amniotic fluid was shown to be the most accurate test for diagnosis of intra-amniotic inflammation, whereas addition of the MR score to the Gram stain provides the best combination of tests to rapidly predict infection.
Preterm labour and resultant preterm birth are the most important problems in perinatology. Countless efforts have failed to establish a single effective treatment of preterm labour, partly because the mechanisms regulating the uterus and cervix during pregnancy are not well understood. New knowledge is needed to inhibit early progression of labour (uterine contractility and cervical ripening), and adequate quantitative tools to evaluate the uterus and cervix during pregnancy are lacking. In this review, we outline studies showing that the uterus (myometrium) and cervix pass through a conditioning step in preparation for labour. This step is not easily identifiable with present methods to assess the uterus or cervix. In the uterus, this seemingly irreversible step consists of changes in the electrical properties to make muscle more excitable and responsive to produce forceful contractions. In the cervix, the step consists of softening of the connective tissue components. Progesterone appears to have a dominant role in controlling both the uterus and cervix, as antiprogestins induce early, preterm conditioning leading to preterm labour. Apparently, nitric oxide (NO) also controls conditioning of the uterus and cervix. In the uterus, NO, in concert with progesterone, inhibits uterine contractility. At term, NO production by the uterus and placenta are decreased and allow labour to progress. In contrast, NO in the cervix increases at the end of pregnancy and it may be the final pathway for stimulating cervical ripening by activation of metalloenzymes. The progress of labour can be assessed non-invasively using electromyographic (EMG) signals from the uterus (the driving force for contractility) recorded from the abdominal surface. Uterine EMG bursts detected in this manner characterize uterine contractile events during human and animal pregnancy. A low uterine EMG activity, measured transabdominally throughout most of pregnancy, rises dramatically during labour. EMG activity also increases substantially during preterm labour in humans and rats. This method may be used one day to predict impending preterm labour and identify control steps and treatments. A quantitative method also assesses the cervix, using an optical device which measures collagen fluorescence in the cervix. The collascope estimates cervical collagen content from a fluorescent signal generated when collagen cross-links are illuminated with excitation light of about 340 nm. The system has proved useful in rats and humans at various stages of pregnancy, and indicates that cervical softening occurs progressively in the last one-third of pregnancy. In rats, collascope readings correlate with resistance measurements made in the isolated cervix, which may help to assess cervical function during pregnancy, and indicate control and treatments.
Objective To determine whether routine measurement of second-trimester transvaginal cervical length by ultrasound in low-risk singleton pregnancies is a costeffective strategy. Methods
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