Presence Of PDA Research Articles

Screening for Retinopathy of Prematurity in Neonatal Intensive Care Unit in Ain Shams University Hospital

Abstract Purpose to evaluate the Retinopathy of prematurity prevalence and screening outcome in a tertiary hospital in Cairo, Egypt. Also, to assess the risk factors for its development and to suggest modifications to the international guidelines for screening for Retinopathy of prematurity to fit the Egyptian population. Methods A prospective observational study was carried out in Neonatal Intensive Care Unit (NICU) in Ain Shams University Hospital. In this study 159 premature infants born in the period between 1 September 2018 to 1 September 2021 were screened for Retinopathy of Prematurity (ROP). Screening was based on the most inclusive criteria reported to date. All premature infants with gestational age (GA) of ≤ 34 weeks or birth weight (BW) of ≤ 2000 grams were included. Infants were also included if GA > 34 weeks or BW > 2000 grams, but multiple co-morbidities existed. The prevalence of retinopathy of prematurity and plus disease and their correlation with risk factors of interest were studied. Results The gestational age of the included infants ranged from 27 to 36 weeks, with a mean (SD) of 31.87 (± 1.81) weeks. Infants had birth weight ranging from 640 to 3900 grams, with a mean (SD) of 1784.71 (± 560.30) grams. The prevalence of ROP changes more than stage 0 in the screened infants was 25.8% (41 infants) with 7.3% of cases (11 infants) showing plus disease and 6.3% of cases (10 infants) showing severe changes that needed treatment. Of those, 2 cases (20%) fell outside the British Guideline’s criteria for Screening. there was a highly significant (p < 0.0001) correlation between appearance of Retinopathy of prematurity changes more than stage 0 and low gestational age, low birth weight of the screened infants, receiving mechanical ventilation, respiratory distress syndrome stage, presence of Necrotizing enterocolitis, Intraventricular haemorrhage and blood transfusion. On the other hand, no significant correlation was found between appearance of Retinopathy of prematurity changes more than stage 0 and gender (p = 0.911), presence of PDA (p = 0.187), or sepsis (p = 0.998). Conclusion Retinopathy of prematurity is a significant problem in the premature infants in Cairo, Egypt. Extremely premature infants with lower birth weight are more prone to develop this disease. However, cases with higher gestational age and birth weight than mentioned in the British guidelines screening criteria especially with multiple comorbidities showed severe Retinopathy of prematurity changes that needed intervention, which implies the need to develop a screening guideline for the Egyptian population.

Case report: interrupted aortic arch

Introduction: Interrupted aortic arch (IAA) is one of the congenital heart diseases characterized by a complete anatomical and luminal disruption between the ascending and descending aorta. It is frequently accompanied by other congenital heart defects, such as PDA and VSD. IAA in adults is exceptionally rare. The presence of collateral circulation and PDA are key factors for patient survival. Thorax CTA is an excellent modality for imaging and diagnosis, ensuring that appropriate treatment can be carried out. Case Presentation: An 18-year-old male patient presented with complaints of worsening shortness of breath 10 days prior to the examination. The shortness of breath has been experienced since school age, often occurring during exercise and strenuous activity. Thorax CTA results indicated IAA type A subtype 1 according to Celoria and Patton classification, PDA type A according to Krichenko classification, perimembranous VSD, cardiomegaly, and pulmonary hypertension. Conclusion: IAA in adults is exceptionally rare. Adult IAA patients may exhibit no symptoms or may present with symptoms of CHF. Thorax CTA is one of the modalities employed to confirm the diagnosis of IAA. It can visualize the interruption and separation between the ascending and descending aorta, as well as the associated anomalies. The presence of a PDA and VSD ensures that the descending thoracic aorta distal to the defect continues to receive some oxygenated blood from the heart. Thorax CTA plays a pivotal role in establishing cases of IAA, as it helps clinicians to make a quick and accurate diagnosis.

Injectable Bioadhesive Hydrogels Scavenging ROS and Restoring Mucosal Barrier for Enhanced Ulcerative Colitis Therapy.

Despite the progress in the therapy of ulcerative colitis (UC), long-lasting UC remission can hardly be achieved in the majority of UC patients. The key pathological characteristics of UC include an impaired mucosal barrier and local inflammatory infiltration. Thus, a two-pronged approach aiming at repairing damaged mucosal barrier and scavenging inflammatory mediators simultaneously might hold great potential for long-term remission of UC. A rectal formulation can directly offer preferential and effective drug delivery to inflamed colon. However, regular intestinal peristalsis and frequent diarrhea in UC might cause transient drug retention. Therefore, a bioadhesive hydrogel with strong interaction with intestinal mucosa might be preferable for rectal administration to prolong drug retention. Here, we designed a bioadhesive hydrogel formed by the cross-linking of sulfhydryl chondroitin sulfate and polydopamine (CS-PDA). The presence of PDA would ensure the mucosa-adhesive behavior, and the addition of CS in the hydrogel network was expected to achieve the restoration of the intestinal epithelial barrier. To scavenge the key player (excessive reactive oxygen species, ROS) in inflamed colon, sodium ferulic (SF), a potent ROS inhibitor, was incorporated into the CS-PDA hydrogel. After rectal administration, the SF-loaded CS-PDA hydrogel could adhere to the colonic mucosa to allow prolonged drug retention. Subsequently, sustained SF release could be achieved to persistently scavenge ROS in inflammatory areas. Meanwhile, the presence of CS would promote the restoration of the mucosal barrier. Ultimately, scavenging ROS and restoring the mucosal barrier could be simultaneously achieved via this SF-loaded bioadhesive hydrogel scaffold. Our two-pronged approach might provide new insight for effective UC treatment.

Echocardiographic score to predict neonatal surgery for aortic coarctation in newborns with prenatal suspicion and patent ductus arteriosus

Introduction The evaluation of upcoming Aortic Coarctation (CoA) in new-borns with prenatal suspicion entails a close echocardiographic monitor until Arterial Duct (AD) closure, in a department with pediatric cardiological and surgical expertise. The significant number of false-positive prenatal diagnoses causes parental stress and healthcare costs. Aim The aim of this study was to elaborate an echocardiographic prediction model to be employed at birth when PDA is still present, in patients suspected of CoA during fetal life in order to foretell CoA requiring neonatal surgical intervention. Methods This retrospective monocentric study included consecutive full-term and late preterm neonates with prenatal suspicion of CoA born from 01 January 2007 to 31 December 2020. Patients were divided into two groups according to the need for aortic surgery (CoA - NoCoA). All patients underwent a comprehensive transthoracic echocardiographic exam in presence of PDA. Multivariable logistic regression was used to create a coarctation probability model (CoMOD) including isthmal (D4), transverse arch (D3) diameters, the distance between a left common carotid artery (LCA) and left subclavian artery (LSA), presence/absence of ventricular septal defect (VSD) and bicuspid aortic valve (BAV). Results We enrolled 87 neonates (49 male, 56%). 44 patients developed CoA in need of surgical repair. Our index CoMOD showed an AUC = 0.9382, high sensitivity (91%) and specificity (86%) in the prediction of CoA in neonates with prenatal suspicion. We classified neonates with CoMOD > 0 to be at high risk for surgical correction of CoA, with good PPV (86.9%) and NPV (90.9%). Conclusions CoMOD > 0 is highly suggestive of the need for CoA corrective surgery in newborns with prenatal suspicion.

High‐Radiance Near‐Infrared Perovskite Light‐Emitting Diodes with Improved Roll‐Off Degradation

AbstractThe external quantum efficiency (EQE) of state‐of‐the‐art near‐infrared perovskite light‐emitting diodes (PeLEDs) is now approaching the limit set by the out‐coupling efficiency. However, there is plenty of room for enhancing these devices’ radiance and the EQE roll‐off. This work reports how conductive and passivating additives construct efficient high‐radiance near‐infrared PeLEDs with improved EQE roll‐off. Specifically, the synergistic effect of 1,4‐phenylenediacetic acid (PDA) and 5‐aminovaleric acid (5‐AVA) is used to regulate the quality of the perovskite emissive layer, thereby enhancing the roll‐off threshold of injection currents (a value at which the device EQE or radiance starts degrading). According to in situ structural evolution analyses from the perovskite precursor to the perovskite crystal, the presence of PDA within the perovskite precursor solution can produce an intermediate phase with 5‐AVA and formanmidinium cation, which can retard the perovskite nucleation and crystal growth, leading to improved perovskite film quality. The resulting champion PeLED delivers among the highest radiance of 505 W sr−1 m−2 and a peak EQE of 17.56%. More importantly, the improved PeLED shows a well‐retained radiance of 80% at a current injection density of up to ≈1800 mA cm−1, opening a new avenue for high‐radiance PeLEDs with improved roll‐off degradation.

Finding a biomarker to predict patent ductus arteriosus in preterm babies

Background: Few studies have evaluated the relationship between the presence of PDA and cardiac troponin T (cTnT) levels; however, the results are conflicting. The present study aimed to compare blood cTnT levels among preterm neonates with and without PDA. Methods: A case-control study was conducted at Iranian Hospital in 2021. For all included neonates, echocardiography examination was performed on admission time. According to the clinical presentation and echocardiography findings, preterm neonates were divided into the case (with PDA) and control (without PDA) groups. A blood test was also performed for all participants to detect levels of plasma cTnT. Finally, the levels of plasma cTnI (ng/ml) were compared between the case and control groups. Results: Totally 36 neonates (12 with PDA and 24without PDA) aged 1.972±0.696 days entered the study. The mean neonatal Troponin T level was 116.352±83.470 ng/ml. The results have shown no significant difference between the groups regarding the means of Troponin level (124.506±113.138 and 112.275±66.546; P=0.476). The results have indicated that there were significant and inverse correlations between the cTnT level with the 1st (Correlation Coefficient= -0.450; P=0.006) and 5th (Correlation Coefficient=-0.532; P=0.001) minutes Apgar Scores. This relationship was also observed between the mean of TnT level and maternal gravidity (Correlation Coefficient= -0.356; P=0.033). Conclusion: The results of the present study delineate no correlation between the presence of PDA and increased blood cTnT levels in preterm neonates. While low Apgar scores at 1 and 5 minutes as well as maternal gravidity could significantly change the levels of cardiac troponin T levels.

Incidence and risk factors for retinopathy of prematurity in premature, extremely low birth weight and extremely low gestational age infants

BackgroundThe aim of the study was to determine the incidence and risk factors of retinopathy of prematurity (ROP) in premature, extremely low birth weight (BW, ELBW) and extremely low gestational age (GA, ELGA) infants.MethodsThe medical records of preterm infants who were screened for ROP between January 2012 and December 2020 were retrospectively reviewed. Only one eye of each infant with higher grade ROP was included in the study. BW; GA; medical characteristics; the presence, severity, and need for treatment of ROP were recorded. Infants were divided into groups according to BW (≤1000 g, 1001-1750 g, > 1750 g) and GA (≤25w, 26-28w, 29-31w, 32-34w, ≥35w) and data were analyzed.ResultsData of 2186 infants were evaluated. The overall incidences of any stage ROP and ROP requiring treatment were 43.5 and 8.0%, respectively. These rates were 81.1 and 23.9% in ELBW (≤1000 g) infants and were 92.9 and 64.3% in ELGA (≤25w) infants, respectively. The rates of ROP, the median duration of oxygen therapy and systemic diseases increased significantly as BW and GA decreased. The median duration of oxygen therapy and the rates of sepsis, pulmonary dysplasia (BPD), and intraventricular hemorrhage (IVH) were statistically higher in infants with ROP compared to those without ROP (p < 0.001). Multivariate regression analysis demonstrated that low BW and GA; prolonged duration of oxygen therapy; presence of PDA and necrotizing enterocolitis (NEC) were important risk factors for ROP.ConclusionsELBW and ELGA infants develop higher rates of ROP and severe ROP. Prolonged duration of oxygen therapy, the presence of concomitant neonatal sepsis, BPD, IVH, PDA, and NEC further increases the risk of ROP.

Vancomycin-conjugated polydopamine-coated magnetic nanoparticles for molecular diagnostics of Gram-positive bacteria in whole blood

BackgroundSepsis is caused mainly by infection in the blood with a broad range of bacterial species. It can be diagnosed by molecular diagnostics once compounds in the blood that interfere with molecular diagnostics are removed. However, this removal relies on ultracentrifugation. Immunomagnetic separation (IMS), which typically uses antibody-conjugated silica-coated magnetic nanoparticles (Ab-SiO2-MNPs), has been widely applied to isolate specific pathogens in various types of samples, such as food and environmental samples. However, its direct use in blood samples containing bacteria is limited due to the aggregation of SiO2-MNPs in the blood and inability to isolate multiple species of bacteria causing sepsis.ResultsIn this study, we report the synthesis of vancomycin-conjugated polydopamine-coated (van-PDA-MNPs) enabling preconcentration of multiple bacterial species from blood without aggregation. The presence of PDA and van on MNPs was verified using transmission electron microscopy, X-ray photoelectron spectroscopy, and energy disruptive spectroscopy. Unlike van-SiO2-MNPs, van-PDA-MNPs did not aggregate in the blood. Van-PDA-MNPs were able to preconcentrate several species of Gram-positive bacteria in the blood, lowering the limit of detection (LOD) to 10 colony forming units/mL by polymerase chain reaction (PCR) and quantitative PCR (qPCR). This is 10 times more sensitive than the LOD obtained by PCR and qPCR using van-SiO2-MNPs.ConclusionThese results suggest that PDA-MNPs can avoid aggregation in blood and be conjugated with receptors, thereby improving the sensitivity of molecular diagnostics of bacteria in blood samples.

Reintubation rates after extubation to different non-invasive ventilation modes in preterm infants

IntroductionRespiratory Distress Syndrome (RDS) is a common cause of neonatal morbidity and mortality in premature newborns. In this study, we aim to compare the reintubation rate in preterm babies with RDS who were extubated to Nasal Continuous Positive Airway Pressure (NCPAP) versus those extubated to Nasal Intermittent Positive Pressure Ventilation (NIPPV).MethodsThis is a retrospective study conducted in the Neonatal Intensive Care Unit (NICU) of Women’s Wellness and Research Center (WWRC), Doha, Qatar. The medical files (n = 220) of ventilated preterm infants with gestational age ranging between 28 weeks 0 days and 36 weeks + 6 days gestation and extubated to non-invasive respiratory support (whether NCPAP, NIPPV, or Nasal Cannula) during the period from January 2016 to December 2017 were reviewed.ResultsFrom the study group of 220 babies, n = 97 (44%) babies were extubated to CPAP, n = 77 (35%) were extubated to NIPPV, and n = 46 (21%) babies were extubated to Nasal Cannula (NC). Out of the n = 220 babies, 18 (8.2%) were reintubated within 1 week after extubation. 14 of the 18 (77.8%) were reintubated within 48 h of extubation. Eleven babies needed reintubation after being extubated to NCPAP (11.2%) and seven were reintubated after extubation to NIPPV (9.2%), none of those who were extubated to NC required reintubation (P = 0.203). The reintubation rate was not affected by extubation to any form of non-invasive ventilation (P = 0.625). The mode of ventilation before extubation does not affect the reintubation rate (P = 0.877). The presence of PDA and NEC was strongly associated with reintubation which increased by two and four-folds respectively in those morbidities. There is an increased risk of reintubation with babies suffering from NEC and BPD and this was associated with an increased risk of hospital stay with a P-value ranging (from 0.02–0.003). Using multivariate logistic regression, NEC the NEC (OR = 5.52, 95% CI 1.26, 24.11, P = 0.023) and the vaginal delivery (OR = 0.23, 95% CI 0.07, 0.78, P = 0.018) remained significantly associated with reintubation.ConclusionReintubation rates were less with NIPPV when compared with NCPAP, however, this difference was not statistically significant. This study highlights the need for further research studies with a larger number of neonates in different gestational ages birth weight categories. Ascertaining this information will provide valuable data for the factors that contribute to re-intubation rates and influence the decision-making and management of RDS patients in the future.

Mussel-inspired UV protective organic coatings via layer-by-layer assembly

Layer-by-layer (LbL) deposition technique has been employed to design mussel-inspired UV protective organic coating using polyethylenimine-polydopamine (PEI-PDA) and poly (acrylic acid) (PAA) pairs. The photocatalytic decomposition of RhB (Rhodamine B) is studied inside the multilayer coated glass vials and a 10 BLs (Bilayers) coatings with a thickness of 1 µm reduces the degradation efficiency of the dye by a factor of 7. The nanocomposite films remain stable under a broad range of pH (pH 4 to pH 10) and temperature (250 °C). The presence of PDA in the nanocomposite films offers a substrate independent adhesion and the film has grown conformally on diverse substrates like cotton and poly(ethylene terephthalate) (PET) using spray assisted LbL coating. Moreover, a study has shown that LbL deposited films have better UV protection efficiency compared to traditional “one pot” PDA deposited films. Finally, these environmental friendly multilayer films are able to protect the degradation of conducting poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films from long UV exposure.

To Feed or Not to Feed: A Critical Overview of Enteral Feeding Management and Gastrointestinal Complications in Preterm Neonates with a Patent Ductus Arteriosus.

The management of enteral feeds in preterm infants with a hemodynamically significant patent ductus arteriosus (hs-PDA) is a major challenge for neonatologists due to the fear of gastrointestinal (GI) complications. This review aims to analyze the available evidence on the complex relation between the presence and management of PDA, enteral feeding practices, and GI outcomes in the preterm population. There is limited evidence, based on small and heterogeneous trials, that hs-PDA may affect the splanchnic hemodynamic response to enteral feeds. While the presence of PDA seems a risk factor for adverse GI outcomes, the benefits of feeding withholding during pharmacological PDA treatment are controversial. The lack of robust evidence in support of or against a timely feeding introduction or feeding withholding during pharmacological PDA closure in preterm neonates does not allow to draw any related recommendation. While waiting for further data, the feeding management of this population should be carefully evaluated and possibly individualized on the basis of the infants’ hemodynamic and clinical characteristics. Large, multicentric trials would help to better clarify the physiological mechanisms underlying the development of gut hypoperfusion, and to evaluate the impact of enteral feeds on splanchnic hemodynamics in relation to PDA features and treatment.

One-pot prepared silicon-silver-polydopamine ternary composite anode materials with high specific capacity and cycling stability

The silicon-based materials show high capacities. However, the poor intrinsic conductivity and severe volume change during the process of lithiation and delithiation restrict the application. In this work, the nanoscale silicon (Si) with silver-polydopamine (Ag/PDA) hybrid coating was designed and successfully prepared by a simple one-pot liquid-phase redox reaction method. The electrochemical properties of the anode materials for lithium ion batteries were characterized, and the mechanism for the excellent cycling performance were investigated by cyclic voltammetry (CV), Electrochemical impedance spectra (EIS), scanning electron microscopy (SEM) and the operando visual observation during lithiation/delithiation process. According to the results, the presence of PDA and Ag is advantageous to enhance the electronic conductivity in the charge-discharge process. The Si/Ag/PDA ternary composite electrode exhibits high capacity and more stable cycling characteristics than Si and Si/PDA electrodes especially at large current densities, which remains 1168.8 mAh g−1 and after 100 cycles at 2 A g−1.

Is rescue based treatment or early conservative treatment superior in managing patent ductus arteriosus?

Commentary on: Clyman RI, Liebowitz M, Kaempf J, Erdeve O, Bulbul A, Håkansson S, Lindqvist J, Farooqi A, Katheria A, Sauberan J, Singh J, Nelson K, Wickremasinghe A, Dong L, Hassinger DC, Aucott SW, Hayashi M, Heuchan AM, Carey WA, Derrick M, Fernandez E, Sankar M, Leone T, Perez J, Serize A, the PDA-TOLERATE (PDA: TO LEave it alone or Respond And Treat Early) Trial Investigators. PDA-TOLERATE trial: an exploratory randomized controlled trial of treatment of moderate-to-large patent ductus arteriosus at one week of age. J Pediatr 2018; 205: 41–48.e6. PMID: 30340932. Numerous poor outcomes in premature neonates are attributed to the persistent left-to-right shunt of a PDA, such as pulmonary haemorrhage, bronchopulmonary dysplasia and death. There is also concern that PDAs cause ‘systemic steal’, leading to intraventricular haemorrhage (IVH), hypotension and delay of time to full feeds 1, 2. The PDA is particularly problematic in the extremely premature neonate: Clyman et al. 3 showed spontaneous closure at seven days of life in 98% of those infants born at ≥30 weeks compared to just 13% of infants born at 24 weeks. No trial, however, has definitively shown reduced incidence of BPD or death with either prophylactic indomethacin or closure of the PDA regardless of timing 4. Thus, optimal management of the PDA in premature infants has long been a source of controversy among neonatologists. According to the authors, this study, which they describe as a pilot exploratory trial, had two goals – to evaluate whether there is a difference between presumptive and rescue-based treatment of the PDA on ligation and presence of PDA at discharge, and to obtain data on several secondary outcomes to appropriately power future investigations. This trial addressed the current knowledge gap by focusing solely on infants with moderate-to-large PDAs present after the first week of life and evaluating PDA exposure to assess for long-term outcomes throughout hospitalisation. There was no statistically significant difference, however, in the primary outcome or in many of the pre-specified secondary outcomes. The authors note many limitations of their trial, which can make this paper difficult for clinicians to generalise to their populations. The primary outcome is difficult to apply to clinical practice, as most clinicians are less interested in the presence of PDA as they are in preventing its long-term consequences. The small size of the study and high rate (almost 50%) of rescue treatment in the CT arm could have contributed to the lack of difference in the outcomes of the two groups. Further, the multiple comparisons required for the statistical analysis of groups and subgroups impedes our ability to draw conclusions from the appearance of statistical significance. What the results of this study do suggest is that clinicians should not feel obligated to automatically treat every PDA. Based on the data presented, a reasonable strategy is to follow the infant's clinical status, treating when necessary. With this strategy, about 50% of infants with a persistent PDA may avoid exposure to the harms of NSAIDs and ligation by the time of discharge. This study also highlights the need for larger trials to assess the long-term consequences of prolonged PDA exposure in lower gestational age infants. This study also helps inform future trials about specific sub-populations of infants to include, and about required sample sizes. https://ebneo.org/2019/04/pda-tolerate-trial/ None. This study was funded by grants from the Gerber Foundation, US Public Health Service, National Heart, Lung, and Blood Institute, National Center for Advancing Translational Sciences, and National Institutes of Health and a gift from the Jamie and Bobby Gates Foundation.

Simultaneously enhanced mechanical properties and thermal properties of ultrahigh‐molecular‐weight polyethylene with polydopamine‐coated α‐alumina platelets

AbstractPolydopamine (PDA) was employed to modify micrometric Al2O3 platelets to improve the interfacial compatibility between α‐Al2O3 powder and ultrahigh‐molecular‐weight polyethylene (UHMWPE). The structure of PDA‐coated Al2O3 and UHMWPE composites was investigated via Fourier transform infrared spectroscopy, scanning electron microscopy and X‐ray photoelectron spectroscopy. The thermal stability and mechanical performance of the samples were also evaluated. It is clear that UHMWPE/PDA‐Al2O3 composites exhibit better mechanical properties, higher thermal stability and higher thermal conductivity than UHMWPE/Al2O3 composites, owing to the good dispersion of Al2O3 powder in the UHMWPE matrix and the strong interfacial force between the macromolecules and the inorganic filler caused by the presence of PDA. The tensile strength and the tensile elongation at break of UHMWPE/PDA‐Al2O3 composite with 1 wt% PDA‐Al2O3 are 62.508 MPa and 462%, which are 1.96 and 1.98 times higher than those of pure UHMWPE, respectively. The thermal conductivity of UHMWPE/PDA‐Al2O3 composite increases from 0.38 to 0.52 W m−1 K−1 with an increase in the dosage of PDA‐Al2O3 to 20 wt%. The results show that the prepared PDA‐coated Al2O3 powder can simultaneously enhance the mechanical properties and thermal conductivity of UHMWPE. © 2018 Society of Chemical Industry

Incidence and outcomes of acute kidney injury in extremely-low-birth-weight infants.

BackgroundAcute kidney injury (AKI) is a common event in the neonatal intensive care unit (NICU), especially in extremely-low-birth-weight (ELBW) infants. This cohort study investigated the incidence of and risk factors for AKI in ELBW infants and their overall survival at the postmenstrual age (PMA) of 36 weeks.MethodsAll ELBW infants admitted to our NICU between January 2010 and December 2013 were enrolled. Those who died prior to 72 hours of life, had congenital renal abnormality, or had only one datum of the serum creatinine (SCr) level after the first 24 hours of life were excluded. The criteria used for the diagnosis of AKI was set according to the modified neonatal KDIGO AKI definition.ResultsAKI occurred in 56% of 276 infants. Specifically, stage 1, stage 2, and stage 3 AKI occurred in 30%, 17%, and 9% of ELBW infants, respectively. High-frequency ventilation support (adjusted odds ratio [OR]: 3.4, 95% confidence interval [CI]: 1.78–6.67, p< 0.001), the presence of patent ductus arteriosus (adjusted OR: 4.3, 95% CI: 2.25–8.07, p < 0.001), lower gestational age (adjusted OR for gestational age: 0.7, 95% CI: 0.58–0.83, < 0.001), and inotropic agent use (adjusted OR: 2.6, 95% CI: 1.31–5.21, p = 0.006) were independently associated with AKI. Maternal pre-eclampsia was a protective factor (adjusted OR: 0.4, 95% CI: 0.14–0.97, p = 0.044). Infants with AKI had higher mortality before the PMA of 36 weeks with an adjusted hazard ratio (HR) of 5.34 (95% CI: 1.21–23.53, p = 0.027). Additionally, infants with stage 3 AKI had a highest HR of 10.60, 95% CI: 2.09–53.67, p = 0.004).ConclusionAKI was a very common event (56%) in ELBW infants and was associated with a lower GA, high-frequency ventilation support, the presence of PDA, and inotropic agent use. AKI reduced survival of ELBW infants before the PMA of 36 weeks.

A novel surface plasmon resonance biosensor based on the PDA-AgNPs-PDA-Au film sensing platform for horse IgG detection

Herein we report a novel polydopamine-silver nanoparticle-polydopamine-gold (PDA-AgNPs-PDA-Au) film based surface plasmon resonance (SPR) biosensor for horse IgG detection. The PDA-AgNPs-PDA-Au film sensing platform was built on Au-film via layer-by-layer self-assembly. Ag ion was reduced in situ to AgNPs in presence of PDA. The top PDA layer can prevent AgNPs from being oxidized and connect with antibody via Schiff alkali reaction directly. The morphology and thickness of the modified gold film were characterized using scanning electron microscope and Talystep. Experimental results show that the PDA-AgNPs-PDA-Au film sensing platform is stable, regenerative and sensitive for horse IgG detection. The detection limit of horse IgG obtained with the present biosensor is 0.625μgmL−1, which is 2-fold and 4-fold lower than that obtained with biosensor based on PDA modified Au film and conventional biosensor based on MPA, respectively. Furthermore, when challenged to real serum samples, our sensor exhibited excellent specificity to horse IgG, suggesting its potential for industrial application.

Synthesis, structures and antimicrobial activities of silver(I) complexes derived from 2-propyl-1H-imidazole-4,5-dicarboxylic acid

Two new silver(I) complexes based on propyl-substituted imidazole-4,5-dicarboxylic acid, {[Ag2(Hpimdc)(H2O)](H2O)}n (1) and {[Ag2(Hpimdc)(pda)](2H2O)}n (2) (H3pimdc=2-propyl-1H-imidazole-4,5-dicarboxylic acid; pda=1,2-propanediamine) were synthesized and structurally characterized. The single-crystal X-ray determination reveals that in complexes 1 and 2 the silver atoms are linearly coordinated. Doubly deprotonated µ3-Hpimdc2− ligand in 1 behaves as an N,O-bridging coordiation mode to offer an infinite 1D linear chain, while µ2-Hpimdc2− in 2 adopts an N,N′-bridging mode to give an infinite 1D zigzag chain in the presence of pda as an auxiliary ligand. The adjacent 1D chains in 1 are further linked to form a 2D layer structure by ligand unsupported Ag⋯Ag interactions (Ag1⋯Ag2#=3.088Å and Ag2⋯Ag2#=3.098Å). Antimicrobial testing indicates that complex 2 with MIC100 being 0.19mM was more active against Gram-negative bacteria Escherichia coli (E. coli) than complex 1 with MIC100 being 0.28mM. Complexes 1 and 2 have the slightly different influence on the growth of Gram-positive bacteria Staphylococcus aureus (S. aureus) (MIC100 being 0.28mM for 1 and 0.24mM for 2). Both 1 and 2 exhibit good inhibitory activities against jack bean urease with the respective IC50 values of 1.68±0.07 and 1.85±0.14µM.

Presence of the diatom genus Pseudo-nitzschia and particulate domoic acid in the Golden Horn Estuary (Sea of Marmara, Turkey)

The potentially toxic diatom genus Pseudo-nitzschia and particulate domoic acid (pDA) concentrations were investigated weekly to bi-weekly from October 2013 to September 2014 in the Golden Horn Estuary. Pseudo-nitzschia species were detected in 324 of the 666 samples (∼49%). Two species, Pseudo-nitzschia calliantha and Pseudo-nitzschia pungens, were identified based on the scanning electron microscopy examination. A bloom of P. calliantha occurred between May and June, average cell density, 1.1 × 106 cells L−1 in May. Pseudo-nitzschia calliantha was commoner than P. pungens almost throughout the study period. They occurred over a wide temperature range (7.4–26.3°C) and moderate salinity (5.9–19.9). The highest cell density occurred at 14.7–19.6°C and 18.5–19.0 salinity, in the lower and middle estuary in winter and late spring. Pseudo-nitzschia species were found in very low densities in the upper estuary, which has variable salinity and low light availability due to high concentrations of suspended material. The pDA concentration in seawater was 0.03–1.0 µg L−1. The distribution pattern of pDA coincided with the presence of Pseudo-nitzschia. Pseudo-nitzschia abundance was low in October, when pDA was highest. There was a highly positive correlation between Pseudo-nitzschia abundance and salinity/Secchi depth/pH (p ≤ .001), but a negative correlation with inorganic nutrients and Si:N (p < .001). pDA was positively correlated with temperature/salinity and Secchi depth, but negatively correlated with inorganic nutrients (p < .001). Low light availability and highly variable salinity may limit the growth of Pseudo-nitzschia in the upper estuary and the presence of pDA throughout the study area may be related to transport by particulate matter.

PO-0507 Patent Ductus Arteriosus (pda) In Preterm Infants: Correlating Clinical And Echocardiographic Findings

Objectives To investigate and correlate clinical signs of PDA with echocardiographic findings beyond day 5 of life in preterm infants. Methods Infants ≤33 weeks of gestation and ≤2.0 kg were included in this prospective observational study. The patients with acute illness (eg Sepsis, NEC) and with congenital heart defect were excluded. Demographic (gestational age, birth weight, gender and Apgar scores), clinical (presence of murmur, blood pressure and pulse pressure) and echocardiographic parameters (presence of PDA, PDA size, flow velocity and LA/Ao) were collected. Results 29 neonates met the study criteria and 61 echocardiograms were performed. All except one (VSD) had a structurally normal heart on echocardiogram and the remainder had a PDA alone. 19/28 had both a murmur and PDA while 9 patients had a PDA without a murmur. The mean PDA size in neonates with a clinical murmur was greater than those with no clinical murmur (0.25 vs. 0.16 cm; p 1.2 in 18/28 patients and only 5 had wide pulse pressure. Conclusion Clinical findings alone cannot diagnose a PDA in preterm infants and echocardiogram is required to exclude abnormal anatomy and confirm the presence of a PDA. The pulse pressure is more relevant within first 7 to 10 days of life.

PO-0757 Perinatal Factors In The Development Of Bronchopulmonary Dysplasia

<h3>Background and aims</h3> Aetiology of BPD is multifactorial with prenatal and postnatal factors being involved. First, we aimed to evaluate the association between chorioamnionitis and BPD. Secondly, the effect of other perinatal factors on the risk of developing BPD were analysed. <h3>Methods</h3> Retrospective analysis of all infants with GA &lt;32 weeks or BW &lt;1500 g. admitted into our hospital between 2002–2010. 120 patients who died before 36 weeks of PMA were excluded. <h3>Results</h3> The average GA was: 29,7 ± 3 s; 217/432 (50%) had any type of chorioamnionitis (histological or clínical); 75/432 (17.4%) met diagnostic criteria for BPD at 36 weeks. Univariate analysis: lower GA, any type of chorioamnionitis, DAP and duration of mechanical ventilation (MV) were associated with an increased risk of DBP (p &lt; 0.05). Multivariate analysis: administration of antenatal steroids or chorioamnionitis did not independently modify the risk of BPD. But adding both, the effect became statistically significant protective for BPD (OR 0.52, 95% CI 0.03 to 0.79). Days in MV is the only factor that independently increased the risk of BPD. Neither a lower GA nor the presence of PDA had significantance; but, the risk of BPD was higher in the presence of PDA and MV together: every day in MV increased the risk of BPD (OR 1.130, 95% CI1.001- 1.27). <h3>Conclusions</h3> Chorioamnionitis in coexistence with antenatal corticosteroids decreases the risk of BPD. Mechanical ventilation is the main risk factor for BPD. In the presenceof DAP, ventilation increases the risk of BPD.