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1.
BMC Pregnancy Childbirth ; 24(1): 335, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38698309

ABSTRACT

BACKGROUND: Diabetes mellitus (DM) is the most common metabolic disorder in pregnancy. Women with Type 2 DM seems to have no better perinatal outcomes than those with Type 1 DM. METHODS: Single-center prospective cohort observational study. Pregnant women with diabetes (141 with Type 1 DM and 124 with Type 2 DM) that were followed in the university hospital between 2009 and 2021 were included in this study. Clinical data and obstetric and perinatal outcomes were collected. RESULTS: As expected, women with Type 1 DM were younger and had a longer duration of diabetes than women with Type 2 DM. Obesity and chronic hypertension were higher in the group of women with Type 2 DM and their value of HbA1c in the second and third trimesters were lower than in Type 1 DM. No differences in prematurity were found, but more extreme prematurity was observed in Type 2 DM, as well as a higher rate of congenital malformations. The frequency of hypoglycemia and the weight of the newborn was higher in Type 1 DM. The maternal independent factors related to the weight of the newborn were: the glycemic control at the third trimester, the weight gain during pregnancy, and pregestational BMI. CONCLUSIONS: Newborns born to mothers with Type 1 DM were larger and had a higher frequency of hypoglycemia, while congenital malformations and precocious preterm was more associated to Type 2 DM. Metabolic control, weight gain and pregestational weight were important determinants of both obstetric and neonatal complications.


Subject(s)
Congenital Abnormalities , Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Pregnancy in Diabetics , Premature Birth , Humans , Female , Pregnancy , Pregnancy in Diabetics/epidemiology , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Adult , Prospective Studies , Infant, Newborn , Congenital Abnormalities/epidemiology , Premature Birth/epidemiology , Hypoglycemia/epidemiology , Hypoglycemia/etiology , Birth Weight , Body Mass Index , Glycated Hemoglobin/analysis , Pregnancy Outcome/epidemiology
2.
Nanoscale ; 11(14): 6654-6661, 2019 Apr 04.
Article in English | MEDLINE | ID: mdl-30896703

ABSTRACT

Solid particles adsorbed at fluid interfaces are crucial for the mechanical stability of Pickering emulsions. The key parameter which determines the kinetic and thermodynamic properties of these colloids is the particle contact angle, θ. Several methods have recently been developed to measure the contact angle of individual particles adsorbed at liquid-liquid interfaces, as morphological and chemical heterogeneities at the particle surface can significantly affect θ. However, none of these techniques enables the simultaneous visualization of the nanoparticles and the reconstruction of the fluid interface to which they are adsorbed, in situ. To tackle this challenge, we utilize a newly developed super-resolution microscopy method, called iPAINT, which exploits non-covalent and continuous labelling of interfaces with photo-activatable fluorescent probes. Herewith, we resolve with nanometer accuracy both the position of individual nanoparticles at a water-octanol interface and the location of the interface itself. First, we determine single particle contact angles for both hydrophobic and hydrophilic spherical colloids. These experiments reveal a non-negligible dependence of θ on particle size, from which we infer an effective line tension, τ. Next, we image elliptical particles at a water-decane interface, showing that the corresponding interfacial deformations can be clearly captured by iPAINT microscopy.

3.
Braz J Med Biol Res ; 52(3): e8281, 2019 Mar 25.
Article in English | MEDLINE | ID: mdl-30916221

ABSTRACT

It has been hypothesized that the therapeutic effects of artepillin C, a natural compound derived from Brazilian green propolis, are likely related to its partition in the lipid bilayer component of biological membranes. To test this hypothesis, we investigated the effects of the major compound of green propolis, artepillin C, on model membranes (small and giant unilamelar vesicles) composed of ternary lipid mixtures containing cholesterol, which display liquid-ordered (lo) and liquid-disordered (ld) phase coexistence. Specifically, we explored potential changes in relevant membrane parameters upon addition of artepillin C presenting both neutral and deprotonated states by means of small angle X-ray scattering (SAXS), differential scanning calorimetry (DSC), and confocal and multiphoton excitation fluorescence microscopy. Thermotropic analysis obtained from DSC experiments indicated a loss in the lipid cooperativity of lo phase at equilibrium conditions, while at similar conditions spontaneous formation of unilamellar vesicles from SAXS experiments showed that deprotonated artepillin C preferentially located at the surface of the membrane. Time-resolved experiments using fluorescence microscopy showed that at doses above 100 µM, artepillin C in its neutral state interacted with both liquid-ordered and liquid-disordered phases, inducing curvature stress and promoting dehydration at the membrane interface.


Subject(s)
Lipid Bilayers/chemistry , Liposomes/chemistry , Phenylpropionates/chemistry , 2-Naphthylamine/analogs & derivatives , Calorimetry, Differential Scanning , Cholesterol/chemistry , Laurates , Microscopy, Confocal , Microscopy, Fluorescence , Models, Chemical , Reference Values , Reproducibility of Results , Scattering, Small Angle , Temperature , Time Factors
4.
Braz. j. med. biol. res ; 52(3): e8281, 2019. tab, graf
Article in English | LILACS | ID: biblio-989461

ABSTRACT

It has been hypothesized that the therapeutic effects of artepillin C, a natural compound derived from Brazilian green propolis, are likely related to its partition in the lipid bilayer component of biological membranes. To test this hypothesis, we investigated the effects of the major compound of green propolis, artepillin C, on model membranes (small and giant unilamelar vesicles) composed of ternary lipid mixtures containing cholesterol, which display liquid-ordered (lo) and liquid-disordered (ld) phase coexistence. Specifically, we explored potential changes in relevant membrane parameters upon addition of artepillin C presenting both neutral and deprotonated states by means of small angle X-ray scattering (SAXS), differential scanning calorimetry (DSC), and confocal and multiphoton excitation fluorescence microscopy. Thermotropic analysis obtained from DSC experiments indicated a loss in the lipid cooperativity of lo phase at equilibrium conditions, while at similar conditions spontaneous formation of unilamellar vesicles from SAXS experiments showed that deprotonated artepillin C preferentially located at the surface of the membrane. Time-resolved experiments using fluorescence microscopy showed that at doses above 100 µM, artepillin C in its neutral state interacted with both liquid-ordered and liquid-disordered phases, inducing curvature stress and promoting dehydration at the membrane interface.


Subject(s)
Phenylpropionates/chemistry , Lipid Bilayers/chemistry , Liposomes/chemistry , Reference Values , Temperature , Time Factors , Calorimetry, Differential Scanning , Cholesterol/chemistry , Reproducibility of Results , Microscopy, Confocal , Scattering, Small Angle , Laurates , Microscopy, Fluorescence , Models, Chemical , 2-Naphthylamine/analogs & derivatives
5.
Mol Imaging Biol ; 19(2): 305-314, 2017 04.
Article in English | MEDLINE | ID: mdl-27632424

ABSTRACT

PURPOSE: Human dosimetry studies play a central role in radioligand development for positron emission tomography (PET). Drawing regions of interest (ROIs) on the PET images is used to measure the dose in each organ. In the study aspects related to ROI delineation methods were evaluated for two radioligands of different biodistribution (intestinal vs urinary). PROCEDURES: PET images were simulated from a human voxel-based phantom. Several ROI delineation methods were tested: antero-posterior projections (AP), 3D sub-samples of the organs (S), and a 3D volume covering the whole-organ (W). Inter- and intra-operator variability ROI drawing was evaluated by using human data. RESULTS: The effective dose estimates using S and W methods were comparable to the true values. AP methods overestimated (49 %) the dose for the radioligand with intestinal biodistribution. Moreover, the AP method showed the highest inter-operator variability: 11 ± 1 %. CONCLUSIONS: The sub-sampled organ method showed the best balance between quantitative accuracy and inter- and intra-operator variability.


Subject(s)
Algorithms , Image Processing, Computer-Assisted , Positron-Emission Tomography , Radiometry , Computer Simulation , Humans , Observer Variation , Tissue Distribution
6.
Nanoscale ; 8(16): 8712-6, 2016 Apr 28.
Article in English | MEDLINE | ID: mdl-27055489

ABSTRACT

Understanding interfacial phenomena in soft materials such as wetting, colloidal stability, coalescence, and friction warrants non-invasive imaging with nanometer resolution. Super-resolution microscopy has emerged as an attractive method to visualize nanostructures labeled covalently with fluorescent tags, but this is not amenable to all interfaces. Inspired by PAINT we developed a simple and general strategy to overcome this limitation, which we coin 'iPAINT: interface Point Accumulation for Imaging in Nanoscale Topography'. It enables three-dimensional, sub-diffraction imaging of interfaces irrespective of their nature via reversible adsorption of polymer chains end-functionalized with photo-activatable moieties. We visualized model dispersions, emulsions, and foams with ∼20 nm and ∼3° accuracy demonstrating the general applicability of iPAINT to study solid/liquid, liquid/liquid and liquid/air interfaces. iPAINT thus broadens the scope of super-resolution microscopy paving the way for non-invasive, high-resolution imaging of complex soft materials.

7.
Rev Neurol ; 54(8): 475-8, 2012 Apr 16.
Article in Spanish | MEDLINE | ID: mdl-22492100

ABSTRACT

INTRODUCTION: The clinical diagnosis of encephalitis due to anti-glutamate receptor N-methyl D-aspartate (NMDA) antibodies (anti-NMDA encephalitis) is made more complex by the fact that psychiatric clinical features are usually predominant in the early stages. This can lead to a delay in the diagnosis, treatment and prognosis of the disease. CASE REPORTS: We report on two clinical cases attended by the Child/Youth Psychiatry Section of our hospital, in collaboration with the Paediatric and Neurology services. Case 1: a 4-year-old male who was referred owing to behavioural alterations and the regression of previously acquired skills. Case 2: a 13-year-old female who was admitted due to a behavioural disorder within the context of a possible initial psychotic episode. In both cases appropriate complementary tests were performed, including lumbar puncture and anti-NMDA antibodies, which were positive. Once the diagnosis of anti-NMDA encephalitis had been reached, treatment was started: in the first case, with intravenous perfusion of corticoids and immunoglobulins, while in the second rituximab had to be associated. Both patients progressed towards clinical improvement. CONCLUSIONS: Over the last two years there has been an increase in the number of cases of anti-NMDA encephalitis diagnosed in the child/youth population. It is a neuropsychiatric, autoimmune condition, which can correspond to a paraneoplastic syndrome. Follow-up and transvaginal ultrasonography as well as thoracoabdominal computerised axial tomography scans are recommended for at least two years after diagnosis. Early diagnosis and treatment are important, which means that a multi- and interdisciplinary approach is required.


Subject(s)
Autoantibodies , Encephalitis/immunology , Receptors, N-Methyl-D-Aspartate/immunology , Adolescent , Child, Preschool , Female , Humans , Male
8.
Med Phys ; 39(6Part14): 3770, 2012 Jun.
Article in English | MEDLINE | ID: mdl-28517244

ABSTRACT

PURPOSE: To verify a Tomotherapy plan for a typical head and neck treatment against experimental measurements. METHODS: The treatment plan for a head and neck case was generated by the Tomotherapy treatment planning system (TPS) to deliver ∼70 Gy in 33 sessions to the contoured PTV. The plan was calculated on a CIRS ATOM anthropomorphic phantom that provides a grid spacing of 3×3 cm2 holes to accommodate thermoluminescent detectors (TLD). The plan was verified against experimental measurements carried out by 7 LiF:Mg,Ti (TLD-700) TLD. Up to 20 locations were selected within the irradiated region and three detectors were used simultaneously at each point to decrease the statistical uncertainty. TLD locations were labeled in the planning system and dose comparisons between TPS prediction and experimental measurements were performed in terms of absolute dose to water for a single fraction. We examined the dose from (i) the corresponding 3.5MV Tomo-scan alone and (ii) the complete treatment. TLD-700 were found to fulfill the requirements of reproducibility, linearity and flat energy response in a previous study. In particular, TLD energy response was previously checked for 6 MV flattening filter free and conventional radiation beams under reference conditions. RESULTS: Doses derived from the TPS were in most cases in good agreement (4% on average) with TLD dose measurements within TLD statistical uncertainties (about 3%). Larger discrepancies up to 7% were found for points close to complex tissue inhomogeneities, such as bony structures. Dose from the scanning procedure alone is about 1 % of the dose per fraction. CONCLUSIONS: This work indicates that dose delivery plans created with Tomotherapy TPS are accurate for head and neck tumor localizations.

11.
Phys Rev Lett ; 105(15): 154503, 2010 Oct 08.
Article in English | MEDLINE | ID: mdl-21230911

ABSTRACT

We use a glass-based microfluidic device to study the electric current behavior of an electrospray process in the presence of a coflowing liquid. The current shows strong voltage dependence and weak flow rate dependence, in stark contrast to classical electrospray. By considering that the current is dominated by convection near the apex of the conical meniscus and driven by tangential electric stresses, we quantitatively capture the voltage and flow rate dependence of the current. Our results elucidate the influence of external field strength and open the way to achieve robust electric control of the current and of the drop size in microfluidics.

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