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1.
NPJ Microgravity ; 8(1): 49, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36336703

ABSTRACT

Space-based research can provide a major leap forward in the study of key open questions in the fundamental physics domain. They include the validity of Einstein's Equivalence principle, the origin and the nature of dark matter and dark energy, decoherence and collapse models in quantum mechanics, and the physics of quantum many-body systems. Cold-atom sensors and quantum technologies have drastically changed the approach to precision measurements. Atomic clocks and atom interferometers as well as classical and quantum links can be used to measure tiny variations of the space-time metric, elusive accelerations, and faint forces to test our knowledge of the physical laws ruling the Universe. In space, such instruments can benefit from unique conditions that allow improving both their precision and the signal to be measured. In this paper, we discuss the scientific priorities of a space-based research program in fundamental physics.

2.
Article in English | MEDLINE | ID: mdl-35032892

ABSTRACT

A sensitive and accurate hydrophilic interaction liquid chromatography - tandem mass spectrometry method (HILIC-MS/MS) was developed and validated for the determination of phenylephrine concentration in Dried Blood Spot (DBS) samples from preterm infants, after ocular administration of an ophthalmic solution with phenylephrine. Sample preparation involved the extraction of the analyte from an 85 µL DBS sample with methanol - acetonitrile (50:50, v/v). Chromatographic separation was achieved on an ACQUITY UPLC BEH AMIDE column, under isocratic conditions within a 5 min run. Detection was achieved with a triple quadrupole MS applying electrospray ionization in positive mode. The method was fully validated and proved precise and accurate with in a linear range of 0.59-3.53 ng/ml in blood. The method was developed to provide insights on the level of exposure of infant population to phenylephrine after ocular administration.


Subject(s)
Chromatography, High Pressure Liquid/methods , Dried Blood Spot Testing/methods , Eye Diseases, Hereditary/diagnosis , Infant, Newborn, Diseases/diagnosis , Infant, Premature/blood , Mydriasis/diagnosis , Mydriatics/blood , Phenylephrine/blood , Tandem Mass Spectrometry/methods , Eye Diseases, Hereditary/blood , Female , Humans , Infant , Infant, Newborn , Infant, Newborn, Diseases/blood , Male , Mydriasis/blood , Mydriatics/administration & dosage , Ophthalmic Solutions , Phenylephrine/administration & dosage
3.
Elife ; 102021 02 04.
Article in English | MEDLINE | ID: mdl-33538692

ABSTRACT

During navigation, the visual responses of neurons in mouse primary visual cortex (V1) are modulated by the animal's spatial position. Here we show that this spatial modulation is similarly present across multiple higher visual areas but negligible in the main thalamic pathway into V1. Similar to hippocampus, spatial modulation in visual cortex strengthens with experience and with active behavior. Active navigation in a familiar environment, therefore, enhances the spatial modulation of visual signals starting in the cortex.


Subject(s)
Primary Visual Cortex/physiology , Visual Pathways/physiology , Visual Perception/physiology , Animals , Mice , Neurons/physiology
4.
Curr Biol ; 30(19): 3811-3817.e6, 2020 10 05.
Article in English | MEDLINE | ID: mdl-32763173

ABSTRACT

The visual responses of neurons in the primary visual cortex (V1) are influenced by the animal's position in the environment [1-5]. V1 responses encode positions that co-fluctuate with those encoded by place cells in hippocampal area CA1 [2, 5]. This correlation might reflect a common influence of non-visual spatial signals on both areas. Place cells in CA1, indeed, do not rely only on vision; their place preference depends on the physical distance traveled [6-11] and on the phase of the 6-9 Hz theta oscillation [12, 13]. Are V1 responses similarly influenced by these non-visual factors? We recorded V1 and CA1 neurons simultaneously while mice performed a spatial task in a virtual corridor by running on a wheel and licking at a reward location. By changing the gain that couples the wheel movement to the virtual environment, we found that ∼20% of V1 neurons were influenced by the physical distance traveled, as were ∼40% of CA1 place cells. Moreover, the firing rate of ∼24% of V1 neurons was modulated by the phase of theta oscillations recorded in CA1 and the response profiles of ∼7% of V1 neurons shifted spatially across the theta cycle, analogous to the phase precession observed in ∼37% of CA1 place cells. The influence of theta oscillations on V1 responses was more prominent in putative layer 6. These results reveal that, in a familiar environment, sensory processing in V1 is modulated by the key non-visual signals that influence spatial coding in the hippocampus.


Subject(s)
Spatial Behavior/physiology , Theta Rhythm/physiology , Visual Cortex/physiology , Action Potentials/physiology , Animals , CA1 Region, Hippocampal/physiology , Female , Hippocampus/physiology , Male , Mice , Mice, Inbred C57BL , Neurons/physiology , Pyramidal Cells/physiology , Reward , Visual Cortex/metabolism
5.
Opt Express ; 27(7): 9803-9814, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-31045129

ABSTRACT

We demonstrate theoretically and experimentally a high level of control of the four-wave mixing process in an inert gas-filled inhibited-coupling guiding hollow-core photonic crystal fiber. The specific multiple-branch dispersion profile in such fibers allows both correlated and separable bi-photon states to be produced. By controlling the choice of gas and its pressure and the fiber length, we experimentally generate various joint spectral intensity profiles in a stimulated regime that is transferable to the spontaneous regime. The generated profiles may cover both spectrally separable and correlated bi-photon states and feature frequency tuning over tens of THz, demonstrating a large dynamic control that will be very useful when implemented in the spontaneous regime as a photon pair source.

6.
Phys Rev Lett ; 121(17): 170403, 2018 Oct 26.
Article in English | MEDLINE | ID: mdl-30411932

ABSTRACT

Einstein-Podolsky-Rosen steering is known to be a key resource for one-sided device-independent quantum information protocols. Here we demonstrate steering using hybrid entanglement between continuous- and discrete-variable optical qubits. To this end, we report on suitable steering inequalities and detail the implementation and requirements for this demonstration. Steering is experimentally certified by observing a violation by more than 5 standard deviations. Our results illustrate the potential of optical hybrid entanglement for applications in heterogeneous quantum networks that would interconnect disparate physical platforms and encodings.

7.
Nature ; 562(7725): 124-127, 2018 10.
Article in English | MEDLINE | ID: mdl-30202092

ABSTRACT

A major role of vision is to guide navigation, and navigation is strongly driven by vision1-4. Indeed, the brain's visual and navigational systems are known to interact5,6, and signals related to position in the environment have been suggested to appear as early as in the visual cortex6,7. Here, to establish the nature of these signals, we recorded in the primary visual cortex (V1) and hippocampal area CA1 while mice traversed a corridor in virtual reality. The corridor contained identical visual landmarks in two positions, so that a purely visual neuron would respond similarly at those positions. Most V1 neurons, however, responded solely or more strongly to the landmarks in one position rather than the other. This modulation of visual responses by spatial location was not explained by factors such as running speed. To assess whether the modulation is related to navigational signals and to the animal's subjective estimate of position, we trained the mice to lick for a water reward upon reaching a reward zone in the corridor. Neuronal populations in both CA1 and V1 encoded the animal's position along the corridor, and the errors in their representations were correlated. Moreover, both representations reflected the animal's subjective estimate of position, inferred from the animal's licks, better than its actual position. When animals licked in a given location-whether correctly or incorrectly-neural populations in both V1 and CA1 placed the animal in the reward zone. We conclude that visual responses in V1 are controlled by navigational signals, which are coherent with those encoded in hippocampus and reflect the animal's subjective position. The presence of such navigational signals as early as a primary sensory area suggests that they permeate sensory processing in the cortex.


Subject(s)
Hippocampus/physiology , Spatial Behavior/physiology , Spatial Processing/physiology , Visual Cortex/physiology , Animals , Female , Hippocampus/cytology , Male , Mice, Inbred C57BL , Neurons/physiology , Reward , Virtual Reality , Visual Cortex/cytology
8.
Opt Lett ; 42(13): 2583-2586, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28957290

ABSTRACT

We report on the experimental characterization of a novel nonlinear liquid-filled hollow-core photonic crystal fiber for the generation of photon pairs at a telecommunication wavelength through spontaneous four-wave mixing (SFWM). We show that the optimization procedure in view of this application links the choice of the nonlinear liquid to the design parameters of the fiber, and we give an example of such an optimization at telecom wavelengths. Combining the modeling of the fiber and classical characterization techniques at these wavelengths, we identify for the chosen fiber and liquid combination SFWM phase-matching frequency ranges with no Raman scattering noise contamination. This is a first step toward obtaining a telecom band fibered photon-pair source with a high signal-to-noise ratio.

9.
Phys Rev Lett ; 118(7): 070503, 2017 Feb 17.
Article in English | MEDLINE | ID: mdl-28256857

ABSTRACT

Instantaneous quantum computing is a subuniversal quantum complexity class, whose circuits have proven to be hard to simulate classically in the discrete-variable realm. We extend this proof to the continuous-variable (CV) domain by using squeezed states and homodyne detection, and by exploring the properties of postselected circuits. In order to treat postselection in CVs, we consider finitely resolved homodyne detectors, corresponding to a realistic scheme based on discrete probability distributions of the measurement outcomes. The unavoidable errors stemming from the use of finitely squeezed states are suppressed through a qubit-into-oscillator Gottesman-Kitaev-Preskill encoding of quantum information, which was previously shown to enable fault-tolerant CV quantum computation. Finally, we show that, in order to render postselected computational classes in CVs meaningful, a logarithmic scaling of the squeezing parameter with the circuit size is necessary, translating into a polynomial scaling of the input energy.

10.
Nat Commun ; 7: 13251, 2016 11 09.
Article in English | MEDLINE | ID: mdl-27827361

ABSTRACT

Multipartite entangled states are a fundamental resource for a wide range of quantum information processing tasks. In particular, in quantum networks, it is essential for the parties involved to be able to verify if entanglement is present before they carry out a given distributed task. Here we design and experimentally demonstrate a protocol that allows any party in a network to check if a source is distributing a genuinely multipartite entangled state, even in the presence of untrusted parties. The protocol remains secure against dishonest behaviour of the source and other parties, including the use of system imperfections to their advantage. We demonstrate the verification protocol in a three- and four-party setting using polarization-entangled photons, highlighting its potential for realistic photonic quantum communication and networking applications.


Subject(s)
Computer-Aided Design , Electronic Data Processing/methods , Photons , Quantum Theory , Algorithms , Humans , Models, Theoretical
11.
Phys Chem Chem Phys ; 18(47): 32396-32405, 2016 Nov 30.
Article in English | MEDLINE | ID: mdl-27869259

ABSTRACT

The influence of the surface chemistry of polyelectrolyte multilayers (PEMs) on the formation of lipid bilayers is studied here for PEMs with either polyallylamine hydrochloride (PAH) or polydiallyldimethylammonium chloride (PDADMAC) as a polycation as a top layer, and polystyrene sulfonate (PSS) as a polyanion. Small unilamellar vesicles (SUVs) composed of phosphatidyl choline and phosphatidyl serine at a 50 : 50 molar ratio are deposited on top of the PEM films. The assembly of the SUVs into bilayers is studied via a quartz crystal microbalance with dissipation (QCM-D) and fluorescence recovery after photobleaching (FRAP). SUV deposition on PDADMAC/PSS results in vesicle adsorption while on PAH/PSS under the same conditions a bilayer is formed mainly due to weak interactions between the quaternary amines of PDADMAC. FRAP measurements confirm that SUVs are not fused on top of PDADMAC/PSS. The effect of phosphate ions, in solution, on the formation of lipid bilayers is also analysed. X-ray photoelectron spectroscopy shows the complexation of phosphate salts to the primary amines of PAH and no interaction with the quaternary amines of PDADMAC. ζ-potential measurements show a potential close to 0 for the PAH/PSS multilayers in PBS while PDADMAC/PSS displays a potential of 25 mV. A model is presented for the formation of lipid bilayers on PAH/PSS PEMs taking into account the role of phosphate ions in decreasing the electrostatic interactions between SUVs and PEMs and the formation of hydrogen bonds between the phospholipids and the primary amines of PAH.

12.
Nanoscale ; 8(15): 7933-41, 2016 Apr 21.
Article in English | MEDLINE | ID: mdl-27006101

ABSTRACT

Immunostimulating reconstituted influenza virosomes (IRIVs) are liposomes with functional viral envelope glycoproteins: influenza virus hemagglutinin (HA) and neuraminidase intercalated in the phospholipid bilayer. Here we address the fusion of IRIVs to artificial supported lipid membranes assembled on polyelectrolyte multilayers on both colloidal particles and planar substrates. The R18 assay is used to prove the IRIV fusion in dependence of pH, temperature and HA concentration. IRIVs display a pH-dependent fusion mechanism, fusing at low pH in analogy to the influenza virus. The pH dependence is confirmed by the Quartz Crystal Microbalance technique. Atomic Force Microscopy imaging shows that at low pH virosomes are integrated in the supported membrane displaying flattened features and a reduced vertical thickness. Virosome fusion offers a new strategy for transferring biological functions on artificial supported membranes with potential applications in targeted delivery and sensing.


Subject(s)
Virosomes/chemistry , Bioengineering , Colloids , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Humans , Hydrogen-Ion Concentration , Influenza A Virus, H1N1 Subtype/chemistry , Membrane Fusion , Membrane Lipids/chemistry , Membranes, Artificial , Microscopy, Atomic Force , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Quartz Crystal Microbalance Techniques , Virosomes/ultrastructure
13.
Langmuir ; 31(31): 8623-32, 2015 Aug 11.
Article in English | MEDLINE | ID: mdl-26158307

ABSTRACT

The self-assembly of mixed vesicles of zwitterionic phosphatidylcholine (PC) and anionic phosphatidylserine (PS) phospholipids on top of polyelectrolyte multilayers (PEMs) of poly(allylamine hydrochloride) (PAH), as a polycation, and polystyrenesulfonate (PSS), as a polyanion, is investigated as a function of the vesicle composition by means of the quartz crystal microbalance with dissipation (QCM-D), cryo-transmission electron microscopy (Cryo-TEM), atomic force microscopy (AFM), and atomic force spectroscopy (AFS). Vesicles with molar percentages of PS between 50% and 70% result in the formation of lipid bilayers on top of the PEMs. Vesicles with over 50% of PC or over 80% of PS do not assembly into bilayers. AFS studies performed with a PAH-modified cantilever approaching and retracting from the lipid assemblies reveal that the main interaction between PAH and the lipids takes place through hydrogen bonding between the amine groups of PAH and the carboxylate and phosphate groups of PS and with the phosphate groups of PC. The interaction of PAH with PS is much stronger than with PC. AFS measurements on assemblies with 50% PC and 50% PS revealed similar adhesion forces to pure PS assemblies, but the PAH chains can reorganize much better on the lipids as a consequence of the presence of PC. QCM-D experiments show that vesicles with a lipid composition of 50% PC and 50% PS do not form bilayers if PSS is replaced by alginate (Alg) or poly(acrylic acid) (PAA).


Subject(s)
Lipid Bilayers/chemistry , Polyamines/chemistry , Polystyrenes/chemical synthesis , Electrolytes/chemistry , Hydrogen Bonding , Particle Size , Polystyrenes/chemistry
14.
Eur J Pharm Biopharm ; 93: 18-26, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25817600

ABSTRACT

PURPOSE: To investigate the application of water-dispersible poly(lactide)-poly(ethylene glycol) (PLA-PEG) copolymers for the stabilization of graphene oxide (GO) aqueous dispersions and the feasibility of using the PLA-PEG stabilized GO as a delivery system for the potent anticancer agent paclitaxel. METHODS: A modified Staudenmaier method was applied to synthesize graphene oxide (GO). Diblock PLA-PEG copolymers were synthesized by ring-opening polymerization of dl-lactide in the presence of monomethoxy-poly(ethylene glycol) (mPEG). Probe sonication in the presence of PLA-PEG copolymers was applied in order to reduce the hydrodynamic diameter of GO to the nano-size range according to dynamic light scattering (DLS) and obtain nano-graphene oxide (NGO) composites with PLA-PEG. The composites were characterized by atomic force microscopy (AFM), thermogravimetric analysis (TGA), and DLS. The colloidal stability of the composites was evaluated by recording the size of the composite particles with time and the resistance of composites to aggregation induced by increasing concentrations of NaCl. The composites were loaded with paclitaxel and the in vitro release profile was determined. The cytotoxicity of composites against A549 human lung cancer cells in culture was evaluated by flow cytometry. The uptake of FITC-labeled NGO/PLA-PEG by A549 cells was also estimated with flow cytometry and visualized with fluorescence microscopy. RESULTS: The average hydrodynamic diameter of NGO/PLA-PEG according to DLS ranged between 455 and 534 nm, depending on the molecular weight and proportion of PLA-PEG in the composites. NGO/PLA-PEG exhibited high colloidal stability on storage and in the presence of high concentrations of NaCl (far exceeding physiological concentrations). Paclitaxel was effectively loaded in the composites and released by a highly sustained fashion. Drug release could be regulated by the molecular weight of the PLA-PEG copolymer and its proportion in the composite. The paclitaxel-loaded composites exhibited cytotoxicity against A549 cancer cells which increased with incubation time, in conjunction with the increasing with time uptake of composites by the cancer cells. CONCLUSION: Graphene oxide aqueous dispersions were effectively stabilized by water-dispersible, biocompatible and biodegradable PLA-PEG copolymers. The graphene oxide/PLA-PEG composites exhibited satisfactory paclitaxel loading capacity and sustained in vitro drug release. The paclitaxel-loaded composites could enter the A549 cancer cells and exert cytotoxicity. The results justify further investigation of the suitability of PLA-PEG stabilized graphene oxide for the controlled delivery of paclitaxel.


Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Drug Carriers , Graphite/chemistry , Oxides/chemistry , Paclitaxel/chemistry , Polyesters/chemistry , Polyethylene Glycols/chemistry , Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Agents, Phytogenic/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Chemistry, Pharmaceutical , Colloids , Delayed-Action Preparations , Drug Stability , Feasibility Studies , Flow Cytometry , Humans , Kinetics , Light , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Microscopy, Atomic Force , Microscopy, Fluorescence , Nanoparticles , Paclitaxel/administration & dosage , Paclitaxel/metabolism , Particle Size , Scattering, Radiation , Sodium Chloride/chemistry , Solubility , Sonication , Technology, Pharmaceutical/methods , Thermogravimetry
16.
Mater Sci Eng C Mater Biol Appl ; 42: 451-60, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25063141

ABSTRACT

The mechanical properties of highly porous (90% porosity) poly(l-lactide) (PLLA), poly(ε-caprolactone) (PCL) and poly(l-lactide/ε-caprolactone) (PLCL) were investigated. Young's modulus of non-porous PLLA, PCL and PLCL dropped from 2263.4, 183.7 and 5.7 MPa to 16.8, 1.0 and 1.0 MPa, respectively, for their ~90% porous counterparts. Elongation at break of PCL decreased noticeably with porosity fraction while PLCL maintained a highly elastomeric character and strain recovery capacity even in the presence of pores. Inorganic bioactive particles (hydroxyapatite or bioglass) were added to confer bioactivity to the aforementioned synthetic bioresorbable polymers, and their effect on the mechanical properties was also investigated. Addition of 15 vol.% of inorganic bioactive particles increased the Young's modulus of highly porous PLLA from 16.2 to ~30 MPa. On the contrary, the difference between Young's modulus of filled and unfilled PCL and PLCL scaffolds was not statistically significant. Finally, an in vitro study of the cytocompatibility and adhesion of adipose derived stem cells (ADSCs) was conducted. The observed viability and excellent adhesion of these cells to both porous and non-porous templates indicate that the employed materials can be good candidates for application in tissue engineering.


Subject(s)
Biocompatible Materials , Caproates/chemistry , Cell Survival/drug effects , Dioxanes/chemistry , Lactones/chemistry , Tissue Scaffolds/chemistry , Adipose Tissue/cytology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Biocompatible Materials/toxicity , Caproates/pharmacology , Caproates/toxicity , Cell Adhesion/drug effects , Cells, Cultured , Dioxanes/pharmacology , Dioxanes/toxicity , Durapatite , Elastic Modulus , Humans , Lactones/pharmacology , Lactones/toxicity , Materials Testing , Porosity , Stem Cells
17.
Hippokratia ; 18(3): 226-30, 2014.
Article in English | MEDLINE | ID: mdl-25694756

ABSTRACT

BACKGROUND/AIM: Therapeutic hypothermia has become an established therapy in asphyxiated neonates with evidence of moderate/severe hypoxic-ischemic encephalopathy. Herein, we describe our recent experience with total body cooling in asphyxiated neonates, which is the first relevant report in Greece. PATIENTS AND METHODS: The medical records of all asphyxiated newborns treated with therapeutic hypothermia in our center between September 2010 and October 2013 were retrospectively reviewed. We recorded data related to neonatal-perinatal characteristics, whole body cooling and outcome. RESULTS: Twelve asphyxiated neonates [median gestational age 38 weeks (36-40)] received whole body cooling (rectal temperature 33.5 ± 0.5 (o)C for 72 hours) during the study period for moderate (n=3) and severe (n=9) hypoxic-ischemic encephalopathy. Cooling was passive in 4 and active in 8 (66.7%) cases. Therapeutic hypothermia was initiated at the median age of 5 hours (0.5-11) after birth. Seven neonates survived (58.3%) to hospital discharge. On follow-up (7-35 months), neurodevelopment outcome was normal in 1 case, while 3, 1 and 2 subjects had mild, moderate and severe impairment, respectively. CONCLUSIONS: Our initial experience with whole body cooling supports its beneficial effect in asphyxiated neonates. This treatment should be offered in all centers involved in the care of such neonates using either simple means (passive cooling) or automated cooling devices. Hippokratia 2014; 18 (3): 226-230.

18.
Int Endod J ; 46(2): 160-8, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22889382

ABSTRACT

AIM: To investigate the expression of two endoplasmic reticulum (ER)-resident key chaperone proteins, ERdj5 and BiP, under the influence of resinous monomers and its relationship with the inhibition of mineralization caused by the monomer 2-hydroxyethyl methacrylate (HEMA). METHODOLOGY: The ERdj5 and BiP expression was studied in vitro, in primary human pulp cell cultures after treatment with three different HEMA concentrations at different time periods. Subsequently, the expression of both the odontoblast markers dentine sialoprotein (DSP) and osteonectin (OSN) was studied in human pulp cells under the same conditions. RESULTS: The ERdj5 and BiP expression was upregulated in the pulp cells. DSP and OSN were largely dispersed in the cytoplasm in control cell cultures but accumulated in a perinuclear area after exposure to HEMA. Their expression levels were not affected. CONCLUSIONS: The increased expression of ERdj5 and BiP may reflect activation of ER stress. DSP and OSN accumulation into the cells may lead to their secretion arrest and inhibition of dentine matrix formation. These events may elucidate the mechanism by which HEMA inhibits the mineralization process.


Subject(s)
Dental Pulp/drug effects , Endoplasmic Reticulum Stress , Methacrylates/adverse effects , Molecular Chaperones/metabolism , Odontoblasts/drug effects , Stress, Physiological , Tooth Calcification/drug effects , Adolescent , Cells, Cultured , Dental Pulp/cytology , Dental Stress Analysis , Endoplasmic Reticulum Chaperone BiP , Extracellular Matrix/drug effects , Extracellular Matrix Proteins/antagonists & inhibitors , Extracellular Matrix Proteins/metabolism , HSP40 Heat-Shock Proteins/metabolism , Heat-Shock Proteins/metabolism , Humans , Odontoblasts/metabolism , Osteonectin/antagonists & inhibitors , Osteonectin/metabolism , Phosphoproteins/antagonists & inhibitors , Phosphoproteins/metabolism , Sialoglycoproteins/antagonists & inhibitors , Sialoglycoproteins/metabolism
19.
Minerva Ginecol ; 64(2): 109-15, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22481621

ABSTRACT

AIM: The aim of the study was to examine the impact of pre-eclampsia on neonatal outcomes of late preterm deliveries. METHODS: A retrospective study was conducted, enrolling pregnancies delivered between 34 0/7 and 36 6/7 weeks of gestation during the period 2004-2007 in a large tertiary center. Pregnancies were divided in group 1, including those complicated with pre-eclampsia and group 2, including normotensive cases. Epidemiological characteristics, mode of delivery and complications contributing in late preterm delivery were initially studied. Neonatal morbidity parameters of our interest included mean Apgar score in the 1st and 5th minute, admission to Neonatal Intensive Care Unit (NICU) and need for emergency intubation. Intrauterine growth retardation (IUGR), low birth weight (LBW) and very LBW (VLBW), respiratory distress syndrome (RDS), hypoglycemia, NICU infection, abnormal cerebral ultrasonographic findings and duration of NICU residence were also compared between the two groups. RESULTS: Out of 363 late preterm pregnancies, 29 (8%) were delivered because of pre-eclampsia. Mean gestational week and birth weight were significantly lower in group 1. The rate of elective caesarean section was also significantly higher in this group. The same observation was made concerning rates of IUGR, LBW and VLBW neonates. Furthermore, incidence of NICU admission and hypoglycemia were significantly higher in the group of infants born by pre-eclamptic mothers. Incidence of RDS and cerebral echo pathology were also higher, but without significant difference when compared to group 2. CONCLUSION: Neonatal adverse outcomes were increased in late preterm infants of pre-eclamptic women in comparison with those of normotensive women.


Subject(s)
Infant, Low Birth Weight , Infant, Premature , Intensive Care Units/statistics & numerical data , Pre-Eclampsia/epidemiology , Premature Birth/epidemiology , Adult , Cesarean Section/statistics & numerical data , Delivery, Obstetric/statistics & numerical data , Elective Surgical Procedures/statistics & numerical data , Female , Fetal Growth Retardation/epidemiology , Greece/epidemiology , Hospitals, Maternity , Hospitals, University , Humans , Hypoglycemia/epidemiology , Infant, Newborn , Pregnancy , Pregnancy Outcome , Respiratory Distress Syndrome, Newborn/epidemiology , Retrospective Studies
20.
J Clin Endocrinol Metab ; 97(2): E238-42, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22162474

ABSTRACT

CONTEXT: Experimental studies linked gestational diabetes mellitus (GDM) and intrauterine growth restriction (IUGR) with altered expression of the offspring's hypothalamic galanin mRNA, possibly contributing to the development of obesity and metabolic syndrome in later life. We hypothesized that plasma galanin levels at birth would reflect presumably altered hypothalamic galanin expression and production that cannot be assessed in the human offspring. OBJECTIVE: Our objective was to investigate whether neonates born to GDM mothers or being IUGR differ from healthy ones in circulating galanin at birth. DESIGN, PATIENTS, AND METHODS: Twenty-five neonates born to GDM mothers, 25 with IUGR, and 15 healthy neonates (controls) were prospectively studied. Neonatal plasma galanin levels were assayed immediately after birth by using enzyme immunoassay. RESULTS: Neonatal plasma galanin showed a high variability within each group and did not differ significantly among the three groups of neonates. No correlation between plasma galanin and anthropometric maternal and neonatal data was found. Multiple linear regression confirmed that the neonatal group (infants of diabetic mothers, IUGR, and controls) was not an independent predictor for galanin levels at birth after controlling for possible confounders, i.e. maternal body mass index and weight gain during pregnancy and neonatal body mass index. CONCLUSIONS: Circulating galanin levels at birth are not affected by GDM and IUGR, providing no evidence for alternations in hypothalamic galanin expression and secretion in humans, as they were previously documented in experimental models. This fact precludes the use of plasma galanin as an early indicator for the development of obesity and metabolic syndrome in this high-risk population.


Subject(s)
Diabetes, Gestational/blood , Fetal Growth Retardation/blood , Galanin/blood , Parturition/blood , Adult , Case-Control Studies , Diabetes, Gestational/epidemiology , Female , Fetal Blood/chemistry , Fetal Blood/metabolism , Fetal Growth Retardation/epidemiology , Galanin/analysis , Humans , Infant, Newborn , Male , Parturition/metabolism , Pregnancy , Young Adult
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