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Optimal management of patent ductus arteriosus (PDA) is unclear. One treatment, surgical ligation, is associated with adverse outcomes. We reviewed data from the Kids' Inpatient Database (2000-2012) to determine if PDA ligation rates: (1) changed over time, (2) varied geographically, or (3) influenced surgical complication rates. In 2012, 47,900 infants <1500g birth weight were born in the United States, including 2,800 undergoing PDA ligation (5.9%). Ligation was more likely in infants <1000g (85.9% vs. 46.2%), and associated with necrotizing enterocolitis (59.2% vs. 37.5%), BPD (54.6% vs. 15.2%), severe intraventricular hemorrhage (16.4% vs. 5.3%), and hospital transfer (37.6% vs. 16.4%). Ligation rates peaked in 2006 at 87.4 per 1000 hospital births, dropping to 58.8 in 2012, and were consistently higher in Western states. Infants undergoing ligation were more likely to experience comorbidities. Rates of ligation-associated vocal cord paralysis increased over time (1.2-3.9%); however, mortality decreased (12.4-6.5%). Thus, PDA ligation has become less frequent, although infants being ligated are smaller and more medically complex. Despite increase in some complications, mortality rates improved perhaps reflecting advances in care.
Copyright © 2018 Elsevier Inc. All rights reserved.
BACKGROUND AND OBJECTIVE - LP533401 is an inhibitor of tryptophan hydroxylase 1, which regulates serotonin production in the gut. Previous work indicates that LP533401 has an anabolic effect in bone. Thus, we hypothesized that inhibition of gut serotonin production may modulate the host response in periodontal disease. In this study, we aimed to analyze the effects of LP533401 in a rat periodontitis model to evaluate the role of gut serotonin in periodontitis pathophysiology.
MATERIAL AND METHODS - Twenty-four rats were divided into three groups: treated group (T: ligature-induced periodontal disease and LP533401, 25 mg/kg/d) by gavage; ligature group (L: ligature-induced periodontal disease only); and control group (C: without ligature-induced periodontal disease). After 28 d, radiographic alveolar bone support was measured on digital radiographs, and alveolar bone volume fraction, tissue mineral density and trabeculae characteristics were quantified by microcomputed tomography in the right hemi-mandible. Left hemi-mandibles were decalcified and alveolar bone loss, attachment loss and area of collagen in the gingiva were histologically analyzed.
RESULTS - Significant difference between the L and C groups was found, confirming that periodontal disease was induced. We observed no difference between the T and L groups regarding alveolar bone destruction and area of collagen.
CONCLUSION - LP533401 (25 mg/kg/d) for 28 d does not prevent bone loss and does not modulate host response in a rat model of induced periodontal disease.
© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
PURPOSE - Neonates placed on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) undergo either carotid repair or ligation at decannulation. Study aims were to evaluate carotid patency rates after repair and to compare early neurologic outcomes between repaired and ligated patients.
METHODS - A retrospective study of all neonates without congenital heart disease (CHD) who had VA-ECMO between 1989 and 2012 was completed using our institutional ECMO Registry. Carotid patency after repair, neuroimaging studies, and auditory brainstem response (ABR) testing at time of discharge were examined.
RESULTS - 140 neonates were placed on VA-ECMO during the study period. Among survivors, 84% of carotids repaired and imaged remained patent at last study. No significant differences were observed between infants in the repaired and ligated groups regarding diagnosis, ECMO duration, or length of stay. A large proportion (43%) developed a severe brain lesion after VA-ECMO, but few failed their ABR testing. Differences in early neurologic outcomes between the two groups of survivors were not significant.
CONCLUSIONS - At this single institution, carotid patency is excellent following repair at ECMO decannulation. No increased incidence of severe brain lesions or greater neurosensory impairment in the repair group was observed. Further studies are needed to investigate the effects of ligation on longer-term neurocognitive outcomes.
Copyright © 2015 Elsevier Inc. All rights reserved.
Glycine-N-methyltransferase (GNMT) is essential to preserve liver homeostasis. Cirrhotic patients show low expression of GNMT that is absent in hepatocellular carcinoma (HCC) samples. Accordingly, GNMT deficiency in mice leads to steatohepatitis, fibrosis, cirrhosis, and HCC. Lack of GNMT triggers NK cell activation in GNMT(-/-) mice and depletion of TRAIL significantly attenuates acute liver injury and inflammation in these animals. Chronic inflammation leads to fibrogenesis, further contributing to the progression of chronic liver injury regardless of the etiology. The aim of our study is to elucidate the implication of TRAIL-producing NK cells in the progression of chronic liver injury and fibrogenesis. For this we generated double TRAIL(-/-)/GNMT(-/-) mice in which we found that TRAIL deficiency efficiently protected the liver against chronic liver injury and fibrogenesis in the context of GNMT deficiency. Next, to better delineate the implication of TRAIL-producing NK cells during fibrogenesis we performed bile duct ligation (BDL) to GNMT(-/-) and TRAIL(-/-)/GNMT(-/-) mice. In GNMT(-/-) mice, exacerbated fibrogenic response after BDL concurred with NK1.1(+) cell activation. Importantly, specific inhibition of TRAIL-producing NK cells efficiently protected GNMT(-/-) mice from BDL-induced liver injury and fibrogenesis. Finally, TRAIL(-/-)/GNMT(-/-) mice showed significantly less fibrosis after BDL than GNMT(-/-) mice further underlining the relevance of the TRAIL/DR5 axis in mediating liver injury and fibrogenesis in GNMT(-/-) mice. Finally, in vivo silencing of DR5 efficiently protected GNMT(-/-) mice from BDL-liver injury and fibrogenesis, overall underscoring the key role of the TRAIL/DR5 axis in promoting fibrogenesis in the context of absence of GNMT. Overall, our work demonstrates that TRAIL-producing NK cells actively contribute to liver injury and further fibrogenesis in the pathological context of GNMT deficiency, a molecular scenario characteristic of chronic human liver disease.
INTRODUCTION - The goal of the current study was to investigate the effect of aging on the development of endothelial dysfunction in a murine model of sepsis, and to compare it with the effect of genetic deficiency of the endothelial isoform of nitric oxide synthase (eNOS).
METHODS - Cecal ligation and puncture (CLP) was used to induce sepsis in mice. Survival rates were monitored and plasma indices of organ function were measured. Ex vivo studies included the measurement of vascular function in thoracic aortic rings, assessment of oxidative stress/cellular injury in various organs and the measurement of mitochondrial function in isolated liver mitochondria.
RESULTS - eNOS deficiency and aging both exacerbated the mortality of sepsis. Both eNOS-deficient and aged mice exhibited a higher degree of sepsis-associated multiple organ dysfunction syndrome (MODS), infiltration of tissues with mononuclear cells and oxidative stress. A high degree of sepsis-induced vascular oxidative damage and endothelial dysfunction (evidenced by functional assays and multiple plasma markers of endothelial dysfunction) was detected in aortae isolated from both eNOS(-/-) and aged mice. There was a significant worsening of sepsis-induced mitochondrial dysfunction, both in eNOS-deficient mice and in aged mice. Comparison of the surviving and non-surviving groups of animals indicated that the severity of endothelial dysfunction may be a predictor of mortality of mice subjected to CLP-induced sepsis.
CONCLUSIONS - Based on the studies in eNOS mice, we conclude that the lack of endothelial nitric oxide production, on its own, may be sufficient to markedly exacerbate the severity of septic shock. Aging markedly worsens the degree of endothelial dysfunction in sepsis, yielding a significant worsening of the overall outcome. Thus, endothelial dysfunction may constitute an early predictor and independent contributor to sepsis-associated MODS and mortality in aged mice.
OBJECTIVE - We performed a multicenter study of preterm infants, who were about to undergo patent ductus arteriosus ligation, to determine whether echocardiographic indices of impaired myocardial performance were associated with subsequent development of catecholamine-resistant hypotension following ligation.
STUDY DESIGN - A standardized treatment approach for hypotension was followed at each center. Infants were considered to have catecholamine-resistant hypotension if their dopamine infusion was > 15 μg kg(-1)min(-1). Echocardiograms and cortisol measurements were obtained between 6 and 14 h after the ligation (prior to the presence of catecholamine-resistant hypotension).
RESULT - Forty-five infants were enrolled, 10 received catecholamines (6 were catecholamine-responsive and 4 developed catecholamine-resistant hypotension). Catecholamine-resistant hypotension was not associated with decreased preload, shortening fraction or ventricular output. Infants with catecholamine-resistant hypotension had significantly lower levels of systemic vascular resistance and postoperative cortisol concentration.
CONCLUSION - We speculate that low cortisol levels and impaired vascular tone may have a more important role than impaired cardiac performance in post-ligation catecholamine-resistant hypotension.
BACKGROUND - We evaluated the clinical effectiveness of variable courses of paracetamol on patent ductus arteriosus (PDA) closure and examined its effect on the in vitro term and preterm murine ductus arteriosus (DA).
METHODS - Neonates received one of the following three paracetamol regimens: short course of oral paracetamol (SCOP), long course of oral paracetamol (LCOP), and intravenous paracetamol (IVP) for 2-6 d. Pressure myography was used to examine changes in vasomotor tone of the preterm and term mouse DA in response to paracetamol or indomethacin. Their effect on prostaglandin synthesis by DA explants was measured by mass spectroscopy.
RESULTS - Twenty-one preterm infants were included. No changes in PDA hemodynamics were seen in SCOP infants (n = 5). The PDA became less significant and eventually closed in six LCOP infants (n = 7). PDA closure was achieved in eight IVP infants (n = 9). On pressure myograph, paracetamol induced a concentration-dependent constriction of the term mouse DA, up to 30% of baseline (P < 0.01), but required >1 µmol/l. Indomethacin induced greater DA constriction and suppression of prostaglandin synthesis (P < 0.05).
CONCLUSION - The clinical efficacy of paracetamol on PDA closure may depend on the duration of treatment and the mode of administration. Paracetamol is less potent than indomethacin for constriction of the mouse DA in vitro.
OBJECTIVE - To test the hypothesis that an impaired adrenal response to stress might play a role in the hypotension that follows patent ductus arteriosus (PDA) ligation.
STUDY DESIGN - We performed a multicenter study of infants born at <32 weeks' gestation who were about to undergo PDA ligation. Serum adrenal steroids were measured 3 times: before and after a cosyntropin (1.0 μg/kg) stimulation test (performed before the ligation), and at 10-12 hours after the ligation. A standardized approach for diagnosis and treatment of postoperative hypotension was followed at each site. A modified inotrope score (1 × dopamine [μg/kg/min] + 1 × dobutamine) was used to monitor the catecholamine support an infant received. Infants were considered to have catecholamine-resistant hypotension if their greatest inotrope score was >15.
RESULTS - Of 95 infants enrolled, 43 (45%) developed hypotension and 14 (15%) developed catecholamine-resistant hypotension. Low postoperative cortisol levels were not associated with the overall incidence of hypotension after ligation. However, low cortisol levels were associated with the refractoriness of the hypotension to catecholamine treatment. In a multivariate analysis: the OR for developing catecholamine-resistant hypotension was OR 36.6, 95% CI 2.8-476, P = .006. Low cortisol levels (in infants with catecholamine-resistant hypotension) were not attributable to adrenal immaturity or impairment; their cortisol precursor concentrations were either low or unchanged, and their response to cosyntropin was similar to infants without catecholamine-resistant hypotension.
CONCLUSION - Infants with low cortisol concentrations after PDA ligation are likely to develop postoperative catecholamine-resistant hypotension. We speculate that decreased adrenal stimulation, rather than an impaired adrenal response to stimulation, may account for the decreased production.
Copyright © 2014 Elsevier Inc. All rights reserved.
INTRODUCTION - Since the NF-κB pathway regulates both inflammation and host defense, it is uncertain whether interventions targeting NF-κB would be beneficial in sepsis. Based on the kinetics of the innate immune response, we postulated that selective NF-κB inhibition during a defined time period after the onset of sepsis would reduce acute lung injury without compromising bacterial host defense.
METHODS - Mice underwent cecal ligation and puncture (CLP). An NF-κB inhibitor, BMS-345541 (50 µg/g mice), was administered by peroral gavage beginning 2 hours after CLP and repeated at 6 hour intervals for 2 additional doses.
RESULTS - Mice treated with BMS-345541 after CLP showed reduced neutrophilic alveolitis and lower levels of KC in bronchoalveolar lavage fluid compared to mice treated with CLP+vehicle. In addition, mice treated with CLP+BMS had minimal histological evidence of lung injury and normal wet-dry ratios, indicating protection from acute lung injury. Treatment with the NF-κB inhibitor did not affect the ability of cultured macrophages to phagocytose bacteria and did not alter bacterial colony counts in blood, lung tissue, or peritoneal fluid at 24 hours after CLP. While BMS-345541 treatment did not alter mortality after CLP, our results showed a trend towards improved survival.
CONCLUSION - Transiently blocking NF-κB activity after the onset of CLP-induced sepsis can effectively reduce acute lung injury in mice without compromising bacterial host defense or survival after CLP.