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1.
Langmuir ; 39(50): 18208-18214, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38051540

RESUMEN

We investigated the nucleation and growth processes of individual NaCl crystals from an evaporating salt solution that is supersaturated. We find that crystals nucleate at the liquid/vapor interface, resulting in distinct "pendant" crystals, which reach millimeter dimensions. The substantial size of the crystals induces deformation of the interface. This process and the evaporation rate, in turn, determine the final crystal shape, which features a deep central cavity. Our findings reveal that a delicate balance exists between gravity, buoyancy, and the surface tension of the liquid/vapor interface that allows the crystal to remain pendant. When the contact angle of the crystal with the meniscus reaches 90°, the crystal disconnects from the interface and falls into the solution. We quantitatively predict the critical mass at which this occurs.

2.
ACS Omega ; 7(33): 28955-28961, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-36033721

RESUMEN

Iron deficiency leading to anemia is one of the most severe and important nutritional deficiencies in the world today. To combat this deficiency, the fortification of food products with iron is a natural way to increase the global iron uptake. Here, we report a novel strategy for iron encapsulation in NaCl crystals via microscopic inclusions containing dissolved iron salt. The liquid inclusions embedded in the crystal insulate the reactive iron salts from their environment while assuring that iron is in a soluble and bioavailable form. While the size distribution of inclusions remains independent of the evaporation conditions, their density increases during crystallization at lower relative humidity. Using Raman confocal microspectroscopy, we have been able to analyze the morphology, length/thickness ratio, of inclusions and show that inclusions evolve toward a plate-like structure with the increase in size. By growing a pure NaCl shell around the iron-containing NaCl crystals, the stability of the composite crystals can be even further enhanced. The role of halite crystals as a carrier for iron fortification opens the way for the delivery of other types of micronutrients by including them in table salt.

8.
Expert Opin Biol Ther ; 16(8): 1065-74, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27341173

RESUMEN

INTRODUCTION: Although anti-tumour necrosis factor (TNF) agents have caused a paradigm shift in the management of moderate-to-severe Crohn's, they are sometimes associated with diminished or absent response in a considerable proportion of patients. Hence agents targeting pathways other than TNF are needed. Ustekinumab is a monoclonal antibody directed against the p40 subunit of IL-12 and 23. AREAS COVERED: This manuscript summarises the available evidence on the efficacy and safety of Ustekinumab in Crohn's disease through data available from randomised controlled trials and compassionate use programs across the world. EXPERT OPINION: Current literature strongly supports the fact that ustekinumab is clinically efficacious and reasonably safe for induction and maintenance of remission in moderate-to-severe Crohn's disease.


Asunto(s)
Enfermedad de Crohn/tratamiento farmacológico , Ustekinumab/uso terapéutico , Ensayos de Uso Compasivo , Humanos , Interleucina-12/inmunología , Interleucina-23/inmunología , Ustekinumab/inmunología
9.
J Gynecol Obstet Biol Reprod (Paris) ; 45(8): 786-795, 2016 Oct.
Artículo en Francés | MEDLINE | ID: mdl-27312097

RESUMEN

INTRODUCTION: Postpartum depression (PPD) is prevalent (about 10%) with a major impact on the mother and child health. At the hormonal level, poor regulation of oxytocin rate has a key role in depression. Recently, oxytocin has been used on psychiatric therapy, intranasal or intravenously, particularly in mood disorders. But, in obstetrics, this molecule is administered during childbirth. The objective of this study was to determine if intravenous administration of oxytocin could influence thymic state of the mother in the postpartum period. METHODS: Literature review, after consultation of Pubmed and Sciencedirect databases, with the following keywords: oxytocin, postpartum depression, pregnancy, social behavior. RESULTS: The effects of oxytocin in the PPD are part of a multifactorial mechanism (hormonal and social) that influences the hormonal effects of oxytocin. Oxytocin use in therapeutic was able to give conclusive results in psychiatry, the way and the optimal method of administration are not known. PPD is associated with administrated oxytocin during labour. Physiopathology remains unknown. CONCLUSION: It is possible that oxytocin administered during childbirth is related with the onset or worsening of the PPD without defining if it's a cause or a consequence.


Asunto(s)
Depresión Posparto/metabolismo , Oxitocina/metabolismo , Adulto , Depresión Posparto/etiología , Femenino , Humanos , Oxitocina/efectos adversos , Embarazo
12.
Ultrasound Obstet Gynecol ; 48(6): 779-785, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26678354

RESUMEN

OBJECTIVE: To analyze the anatomical relationship between the pubic symphysis and the ischial spines to determine reliable landmarks for the assessment of fetal head descent by intrapartum translabial ultrasound (ITU). METHODS: All computed tomography (CT) scans performed for breech presentation and for twin delivery between 2006 and 2014 in a tertiary university hospital were obtained for measurement and analysis by two operators. The symphysis-left ischial spine angle (SIA) and the symphysis-left ischial spine distance (SID) were measured on three-dimensional reconstructions from the CT volume dataset. We calculated intra- and interobserver agreements for SIA and SID with 95% prediction intervals, created Bland-Altman plots with 95% limits of agreement and estimated the intraclass correlation coefficient (ICC). A sagittal plane projection from the SIA enabled calculation of a sagittal angle, corresponding to the angle of progression (AoP) on ITU. RESULTS: SIA and SID were obtained from CT images from 458 women. Reproducibility was good for both SIA (intraobserver ICC, 0.94 (95% CI, 0.88-0.97) and interobserver ICC, 0.81 (95% CI, 0.66-0.92)) and SID (intraobserver ICC, 0.92 (95% CI, 0.82-0.97) and interobserver ICC, 0.83 (95% CI, 0.73-0.92)). The median SIA was 106° (interquartile range (IQR), 105-109°) and median SID was 26.1 (IQR, 23.4-29.5) mm. SIA and SID were not correlated with pelvic diameter or height. The 50th percentile of AoP was 110°. CONCLUSION: Knowledge of the anatomical relationship between the pubic symphysis and ischial spines makes it possible to establish a sonographic method for assesssing fetal head descent by taking into account the level of the ischial spines. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Cabeza/diagnóstico por imagen , Isquion/anatomía & histología , Sínfisis Pubiana/anatomía & histología , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Prenatal/métodos , Adulto , Femenino , Cabeza/embriología , Humanos , Isquion/diagnóstico por imagen , Edad Materna , Imagen Multimodal , Embarazo , Tercer Trimestre del Embarazo , Sínfisis Pubiana/diagnóstico por imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
J Gynecol Obstet Biol Reprod (Paris) ; 44(10): 1101-10, 2015 Dec.
Artículo en Francés | MEDLINE | ID: mdl-26530173

RESUMEN

OBJECTIVE: To provide recommendations on maternal care after vaginal delivery, and management of complications in immediate post-partum period. METHODS: Bibliographic research from the Pubmed database and recommendations issued by the main scientific societies, and assignment of a level of evidence and a recommendation grade. RESULTS: After a vaginal delivery, monitoring of blood pressure, heart rate, bleeding, uterine involution, genital pain, urination, temperature, transit and signs of phlebitis is recommended (professional consensus). Post-partum Anemia is defined by a hemoglobin<11 g/dL at 48 hours (grade C). Anemia must be searched only in women who have bled during delivery or who present symptoms of anemia (professional consensus). Oral iron supplementation is only proposed in cases of biologically proven anemia (professional consensus). In case of post-partum hypertension or de novo preeclampsia, the prescription rules for antihypertensive treatments and magnesium sulfate are the same as in prenatal period (professional consensus). Oral NSAIDs are effective for perineal pain and uterine involution (EL2). In case of broken down perineal wounds following childbirth, there is no argument in favor of suturing or not suturing, however the suturing is to be preferred for large dehisced perineal wounds (professional consensus). Infection of perineal scar justifies an oral broad-spectrum antibiotics, in addition to local nursing (professional consensus). In case of obstetric anal sphincter injuries, an antibiotic prophylaxis is recommended (grade B). Hygiene advice should be given to all women who had an episiotomy or a perineal tear (professional consensus). The only etiological treatment of post-dural puncture headache is the blood patch (EL2). It must not be carried out before 48 hours (professional consensus). Thromboembolic risk after a vaginal birth is about 1‰ (EL2). The prescription of thromboprophylaxis with LMWH and graduated compression stockings should be based on risk factors (professional consensus). CONCLUSION: During the immediate post-partum period, complications may be unrecognized or confused with the natural post-partum evolution, which implies a strong vigilance from practitioners. This vigilance is all the more necessary that the maternal residence durations are shortened.


Asunto(s)
Parto Obstétrico/rehabilitación , Complicaciones del Trabajo de Parto/terapia , Atención Posnatal , Guías de Práctica Clínica como Asunto , Trastornos Puerperales/terapia , Consenso , Parto Obstétrico/efectos adversos , Parto Obstétrico/estadística & datos numéricos , Femenino , Humanos , Recién Nacido , Complicaciones del Trabajo de Parto/epidemiología , Atención Posnatal/métodos , Atención Posnatal/normas , Atención Posnatal/estadística & datos numéricos , Periodo Posparto , Pautas de la Práctica en Medicina/normas , Pautas de la Práctica en Medicina/estadística & datos numéricos , Embarazo , Trastornos Puerperales/epidemiología , Vagina
17.
Ultrasound Obstet Gynecol ; 45(3): 267-72, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24817098

RESUMEN

OBJECTIVE: In the first trimester of pregnancy, a biparietal diameter (BPD) below the 5(th) percentile is a simple marker that enables the prenatal detection of half of all cases of open spina bifida. We hypothesized that relating the BPD measurement to the transverse abdominal diameter (TAD) might be another simple and effective screening method. In this study we assessed the performance of using the BPD/TAD ratio during the first trimester of pregnancy in screening for open spina bifida. METHODS: A total of 20,551 first-trimester ultrasound scans (11-13 weeks' gestation), performed between 2000 and 2013, were analyzed retrospectively; there were 26 cases of open spina bifida and 17,665 unaffected pregnancies with a crown-rump length of 45-84 mm and a record of both BPD and TAD measurements. RESULTS: The mean (± SD) BPD/TAD ratio was 1.00 ± 0.06 for fetuses with spina bifida and 1.13 ± 0.06 for those without (P < 0.0001). A BPD ≤ 5(th) percentile enabled the prenatal detection of 46.2% of spina bifida cases, while a BPD/TAD ratio of ≤ 1.00 detected 69.2%. If we considered cases in which either BPD was ≤ 5(th) percentile or BPD/TAD ratio was ≤ 1, we identified 76.9% of cases. In the latter case, the false-positive rate was 5.1%, while that for using a combination of both BPD ≤ 5th percentile and BPD/TAD ratio ≤ 1 was 0.6%, with a sensitivity of 38.5%. The positive predictive value of using a combination of BPD ≤ 5th percentile and BPD/TAD ratio ≤ 1 for detecting spina bifida was 8.5%. CONCLUSIONS: Between 11 and 13 weeks' gestation, relating BPD to TAD improves considerably the diagnostic performance of using BPD measurement alone in screening for open spina bifida. Screening using this marker is simple and applicable to a large population.


Asunto(s)
Abdomen/patología , Primer Trimestre del Embarazo , Espina Bífida Quística/diagnóstico , Ultrasonografía Prenatal , Abdomen/diagnóstico por imagen , Abdomen/embriología , Adulto , Cefalometría , Largo Cráneo-Cadera , Femenino , Edad Gestacional , Humanos , Embarazo , Estudios Retrospectivos , Sensibilidad y Especificidad , Espina Bífida Quística/diagnóstico por imagen , Espina Bífida Quística/embriología
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