Detection of peptide-based nanoparticles in blood plasma by ELISA

Aims: The aim of the current study was to develop a method to detect peptide-linked nanoparticles in blood plasma. Materials & Methods: A convenient enzyme linked immunosorbent assay (ELISA) was developed for the detection of peptides functionalized with biotin and fluorescein groups. As a proof of principle, polymerized pentafluorophenyl methacrylate nanoparticles linked to biotin-carboxyfluorescein labeled peptides were intravenously injected in Wistar rats. Serial blood plasma samples were analyzed by ELISA and by liquid chromatography mass spectrometry (LC/MS) technology. Results: The ELISA based method for the detection of FITC labeled peptides had a detection limit of 1 ng/mL. We were able to accurately measure peptides bound to pentafluorophenyl meth-acrylate nanoparticles in blood plasma of rats, and similar results were obtained by LC/MS. Conclusions: We detected FITC-labeled peptides on pentafluorophenyl methacrylate nanoparticles after injection in vivo. This method can be extended to detect nanoparticles with different chemical compositions

Proposed clinical management of pregnancies after combined screening for pre-eclampsia at 35-37 weeks' gestation

Objective: To estimate the patient-specific risk of preeclampsia (PE) at 35-37 weeks’ gestation by a combination of maternal characteristics and medical history with multiple of the median (MoM) values of mean arterial pressure (MAP), uterine artery pulsatility index (UTPI), serum placental growth factor (PLGF) and serum soluble fms-like tyrosine kinase-1 (sFLT-1) and stratify women into high-, intermediate- and low-risk management groups. Methods: This was a prospective observational study in women attending for a third-trimester ultrasound scan at 35-37 weeks as part of routine pregnancy care. Patient-specific risks of delivery with PE at 40 weeks’ gestation was estimated. Results: The study population of 3,703 singleton pregnancies included 38 (1.0%) with PE at 40 weeks. Using a risk cut-off for PE at <4 weeks of 1 in 50 to define the high-risk group and a risk cut-off of <1 in 100 for PE at <42 weeks’ gestation to define the low-risk group, the proportion of the population stratified into high-, intermediate- and low-risk was about 12.7%, 28.8% and 58.5%, respectively. The high-risk group contained 92% of pregnancies with PE at 40 weeks. The intermediate-risk group contained a further 27% of women with PE at >40 weeks. In the low-risk group, none of the women developed PE at 40 weeks’ gestation. Conclusion: The study presents risk stratification of PE by the combined test at 35-37 weeks aiming to identify a high-risk group in need of intensive monitoring from the time of the initial assessment and up to 40 weeks’ gestation, an intermediate-risk group in need of reassessment at 40 weeks’ gestation and a low-risk group which can be reassured that they are unlikely to develop PE

Biophysical and biochemical markers at 30-34 weeks' gestation in the prediction of adverse perinatal outcome

Objective: To investigate the potential value of biophysical and biochemical markers at 30 34 weeks’ gestation in the prediction of adverse perinatal outcome. Methods: Screening study in 8,268 singleton pregnancies at 30 34 weeks. Estimated fetal weight (EFW), uterine artery pulsatility index (PI) PI), umbilical artery PI, fetal middle cerebral artery (MCA) PI, mean arterial pressure (MAP), serum placental growth factor (PLGF and soluble fms-like tyrosine kinase-1 (sFlt 1) were measured. The detection rate (DR) and false positive rate (FPR) of screening by each biomarker were estimated for stillbirth, preeclampsia, delivery of small for gestational age (SGA) neonate, cesarean section for fetal distress b efore or during labor, umbilical arterial cord blood pH <7.0 or umbilical venous blood pH <7.1, Apgar score <7 at 5 minutes and admission to the neonatal unit (NNU). Results: Multivariable regression analysis demonstrated that significant predict ion of P E was provided by PLGF, sFlt 1, MAP and MCA PI with DR of 98% of PE delivering at <37 weeks’ gestation and 56% of those delivering at 37 weeks , at 10% FPR. Prediction of SGA was provided by EFW, PLGF, sFlt 1, uterine artery PI, umbilical artery PI, and MC A PI with DR of 88% of SGA at <37 and 51% at 37 weeks’ gestation, at 10% FPR. Prediction of stillbirth was provided by EFW, uterine artery PI and MCA PI with DR of 30 % at 10% Prediction of cesarean section for fetal distress before labor was provided by EFW, sFlt 1, uterine artery PI and umbilical artery PI with DR of 90 %, at 10% FPR. Prediction of fetal distress in labor was provided by EFW and sFlt 1 with DR of 16 %, at 10% FPR. There were no significant differences from the normal outcome group in a ny of the biomarkers for low cord blood pH, low Apgar score or NNU admission for cases other than those with PE and / or SGA. Conclusion: At 30 34 weeks’ gestation, biomarkers of impaired placentation and fetal hypoxemia provide good prediction of PE , SGA and fetal distress before labor, but poor or no prediction of stillbirth and adverse events in labor or after birt

Proposed clinical management of pregnancies after combined screening for pre-eclampsia at 30-34 weeks' gestation

Objective: To estimate the patient-specific risk of preeclampsia (PE) at 30-34 weeks’ gestation by a combination of maternal characteristics and medical history with multiple of the median (MoM) values of mean arterial pressure, uterine artery pulsatility index, serum the median (MoM) values of mean arterial pressure, uterine artery pulsatility index, serum placental growth factor and serum soluble fmsm-like tyrosine kinase-1 and stratify women into high-, intermediate- and low-risk management groups. Methods: This was a prospective observational study in women attending for a third-trimester ultrasound scan at 30-34 weeks as part of routine pregnancy care. Patient-specific risks of delivery with PE at <4 weeks from assessment and at <40 weeks’ of delivery with PE at <4 weeks from assessment and at <40 weeks’ gestation were calculated using the competing risks model to combine the prior risk from maternal characteristics and medical history with MoM values of MAP, UTPI, PLGF and sFLT-1. On the basis of these risks the population was stratified into high-, intermediate- and low-risk groups. Different risk cut-offs were used to vary the proportion of the population stratified into each risk category and the performance of screening for delivery with PE at <4 weeks and delivery with PE from four weeks after assessment and up to 40 weeks’ gestation (PE 4w-40GW) was estimated. Results: The study population of 8,128 singleton pregnancies included 234 (2.9%) that subsequently developed PE. Using a risk cut-off for PE at <4 weeks of 1 in 50 and a risk cut-off of 1 in 150 for PE at <40 weeks’ gestation the proportion of the population stratified into high-, intermediate- and low-risk was about 3%, 26% and 71%, respectively. The high-risk group contained 90% of pregnancies with PE at at <4 weeks and 40% of those with PE at 4w-40GW. The intermediate-risk group contained a further 49% of women with PE at 4w-40GW. In the low-risk group, none of the women developed PE at <4 weeks and only 0.3% developed PE at 4w-40GW. Conclusion: The study presents risk stratification of PE by the combined test at 30-34 weeks aiming to identify a high-risk group in need of intensive monitoring from the time of the initial assessment and up to 40 weeks’ gestation and an intermediate-risk group, in need of monitoring starting from four weeks after the initial assessment and up to 40 weeks’ gestation. All pregnancies would need to be reassessed at 40 weeks’ gestation

Detection of Peptide-Based Nanoparticles in Blood Plasma by ELISA

Aims The aim of the current study was to develop a method to detect peptide-linked nanoparticles in blood plasma. Materials & Methods A convenient enzyme linked immunosorbent assay (ELISA) was developed for the detection of peptides functionalized with biotin and fluorescein groups. As a proof of principle, polymerized pentafluorophenyl methacrylate nanoparticles linked to biotin-carboxyfluorescein labeled peptides were intravenously injected in Wistar rats. Serial blood plasma samples were analyzed by ELISA and by liquid chromatography mass spectrometry (LC/MS) technology. Results The ELISA based method for the detection of FITC labeled peptides had a detection limit of 1 ng/mL. We were able to accurately measure peptides bound to pentafluorophenyl methacrylate nanoparticles in blood plasma of rats, and similar results were obtained by LC/MS. Conclusions We detected FITC-labeled peptides on pentafluorophenyl methacrylate nanoparticles after injection in vivo. This method can be extended to detect nanoparticles with different chemical compositions

Marine Tar Residues: a Review

Abstract Marine tar residues originate from natural and anthropogenic oil releases into the ocean environment and are formed after liquid petroleum is transformed by weathering, sedimentation, and other processes. Tar balls, tar mats, and tar patties are common examples of marine tar residues and can range in size from millimeters in diameter (tar balls) to several meters in length and width (tar mats). These residues can remain in the ocean envi-ronment indefinitely, decomposing or becoming buried in the sea floor. However, in many cases, they are transported ashore via currents and waves where they pose a concern to coastal recreation activities, the seafood industry and may have negative effects on wildlife. This review summarizes the current state of knowledge on marine tar residue formation, transport, degradation, and distribution. Methods of detection and removal of marine tar residues and their possible ecological effects are discussed, in addition to topics of marine tar research that warrant further investigation. Emphasis is placed on ben-thic tar residues, with a focus on the remnants of the Deepwater Horizon oil spill in particular, which are still affecting the northern Gulf of Mexico shores years after the leaking submarine well was capped