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1.
Mov Ecol ; 12(1): 55, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107862

RESUMEN

BACKGROUND: Social network analysis of animal societies allows scientists to test hypotheses about social evolution, behaviour, and dynamic processes. However, the accuracy of estimated metrics depends on data characteristics like sample proportion, sample size, and frequency. A protocol is needed to assess for bias and robustness of social network metrics estimated for the animal populations especially when a limited number of individuals are monitored. METHODS: We used GPS telemetry datasets of five ungulate species to combine known social network approaches with novel ones into a comprehensive five-step protocol. To quantify the bias and uncertainty in the network metrics obtained from a partial population, we presented novel statistical methods which are particularly suited for autocorrelated data, such as telemetry relocations. The protocol was validated using a sixth species, the fallow deer, with a known population size where ∼ 85 % of the individuals have been directly monitored. RESULTS: Through the protocol, we demonstrated how pre-network data permutations allow researchers to assess non-random aspects of interactions within a population. The protocol assesses bias in global network metrics, obtains confidence intervals, and quantifies uncertainty of global and node-level network metrics based on the number of nodes in the network. We found that global network metrics like density remained robust even with a lowered sample size, while local network metrics like eigenvector centrality were unreliable for four of the species. The fallow deer network showed low uncertainty and bias even at lower sampling proportions, indicating the importance of a thoroughly sampled population while demonstrating the accuracy of our evaluation methods for smaller samples. CONCLUSIONS: The protocol allows researchers to analyse GPS-based radio-telemetry or other data to determine the reliability of social network metrics. The estimates enable the statistical comparison of networks under different conditions, such as analysing daily and seasonal changes in the density of a network. The methods can also guide methodological decisions in animal social network research, such as sampling design and allow more accurate ecological inferences from the available data. The R package aniSNA enables researchers to implement this workflow on their dataset, generating reliable inferences and guiding methodological decisions.

2.
PLoS Med ; 21(7): e1004427, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39012912

RESUMEN

BACKGROUND: Cervical cerclage, cervical pessary, and vaginal progesterone have each been shown to reduce preterm birth (PTB) in high-risk women, but to our knowledge, there has been no randomised comparison of the 3 interventions. The SuPPoRT "Stitch, Pessary, or Progesterone Randomised Trial" was designed to compare the rate of PTB <37 weeks between each intervention in women who develop a short cervix in pregnancy. METHODS AND FINDINGS: SuPPoRT was a multicentre, open label 3-arm randomised controlled trial designed to demonstrate equivalence (equivalence margin 20%) conducted from 1 July 2015 to 1 July 2021 in 19 obstetric units in the United Kingdom. Asymptomatic women with singleton pregnancies with transvaginal ultrasound cervical lengths measuring <25 mm between 14+0 and 23+6 weeks' gestation were eligible for randomisation (1:1:1) to receive either vaginal cervical cerclage (n = 128), cervical pessary (n = 126), or vaginal progesterone (n = 132). Minimisation variables were gestation at recruitment, body mass index (BMI), and risk factor for PTB. The primary outcome was PTB <37 weeks' gestation. Secondary outcomes included PTB <34 weeks', <30 weeks', and adverse perinatal outcome. Analysis was by intention to treat. A total of 386 pregnant women between 14+0 and 23+6 weeks' gestation with a cervical length <25 mm were randomised to one of the 3 interventions. Of these women, 67% were of white ethnicity, 18% black ethnicity, and 7.5% Asian ethnicity. Mean BMI was 25.6. Over 85% of women had prior risk factors for PTB; 39.1% had experienced a spontaneous PTB or midtrimester loss (>14 weeks gestation); and 45.8% had prior cervical surgery. Data from 381 women were available for outcome analysis. Using binary regression, randomised therapies (cerclage versus pessary versus vaginal progesterone) were found to have similar effects on the primary outcome PTB <37 weeks (39/127 versus 38/122 versus 32/132, p = 0.4, cerclage versus pessary risk difference (RD) -0.7% [-12.1 to 10.7], cerclage versus progesterone RD 6.2% [-5.0 to 17.0], and progesterone versus pessary RD -6.9% [-17.9 to 4.1]). Similarly, no difference was seen for PTB <34 and 30 weeks, nor adverse perinatal outcome. There were some differences in the mild side effect profile between interventions (vaginal discharge and bleeding) and women randomised to progesterone reported more severe abdominal pain. A small proportion of women did not receive the intervention as per protocol; however, per-protocol and as-treated analyses showed similar results. The main study limitation was that the trial was underpowered for neonatal outcomes and was stopped early due to the COVID-19 pandemic. CONCLUSIONS: In this study, we found that for women who develop a short cervix, cerclage, pessary, and vaginal progesterone were equally efficacious at preventing PTB, as judged with a 20% equivalence margin. Commencing with any of the therapies would be reasonable clinical management. These results can be used as a counselling tool for clinicians when managing women with a short cervix. TRIAL REGISTRATION: EU Clinical Trials register. EudraCT Number: 2015-000456-15, clinicaltrialsregister.eu., ISRCTN Registry: ISRCTN13364447, isrctn.com.


Asunto(s)
Cerclaje Cervical , Cuello del Útero , Pesarios , Nacimiento Prematuro , Progesterona , Humanos , Femenino , Nacimiento Prematuro/prevención & control , Progesterona/administración & dosificación , Progesterona/uso terapéutico , Embarazo , Cerclaje Cervical/métodos , Adulto , Administración Intravaginal , Cuello del Útero/diagnóstico por imagen , Resultado del Tratamiento , Medición de Longitud Cervical
3.
BMJ Open ; 14(6): e079767, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834319

RESUMEN

INTRODUCTION: Severe osteogenesis imperfecta (OI) is a debilitating disease with no cure or sufficiently effective treatment. Mesenchymal stem cells (MSCs) have good safety profile, show promising effects and can form bone. The Boost Brittle Bones Before Birth (BOOSTB4) trial evaluates administration of allogeneic expanded human first trimester fetal liver MSCs (BOOST cells) for OI type 3 or severe type 4. METHODS AND ANALYSIS: BOOSTB4 is an exploratory, open-label, multiple dose, phase I/II clinical trial evaluating safety and efficacy of postnatal (n=15) or prenatal and postnatal (n=3, originally n=15) administration of BOOST cells for the treatment of severe OI compared with a combination of historical (1-5/subject) and untreated prospective controls (≤30). Infants<18 months of age (originally<12 months) and singleton pregnant women whose fetus has severe OI with confirmed glycine substitution in COL1A1 or COL1A2 can be included in the trial.Each subject receives four intravenous doses of 3×106/kg BOOST cells at 4 month intervals, with 48 (doses 1-2) or 24 (doses 3-4) hours in-patient follow-up, primary follow-up at 6 and 12 months after the last dose and long-term follow-up yearly until 10 years after the first dose. Prenatal subjects receive the first dose via ultrasound-guided injection into the umbilical vein within the fetal liver (16+0 to 35+6 weeks), and three doses postnatally.The primary outcome measures are safety and tolerability of repeated BOOST cell administration. The secondary outcome measures are number of fractures from baseline to primary and long-term follow-up, growth, change in bone mineral density, clinical OI status and biochemical bone turnover. ETHICS AND DISSEMINATION: The trial is approved by Competent Authorities in Sweden, the UK and the Netherlands (postnatal only). Results from the trial will be disseminated via CTIS, ClinicalTrials.gov and in scientific open-access scientific journals. TRIAL REGISTRATION NUMBERS: EudraCT 2015-003699-60, EUCT: 2023-504593-38-00, NCT03706482.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Osteogénesis Imperfecta , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Embarazo , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Células Madre Fetales/trasplante , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas , Estudios Multicéntricos como Asunto , Osteogénesis Imperfecta/terapia , Resultado del Tratamiento
4.
Fertil Steril ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38838806

RESUMEN

OBJECTIVE: To determine whether obstetric outcomes differ between women with endometriosis and those without, where all women undergo first-trimester screening for endometriosis. DESIGN: A prospective observational cohort study. SETTING: The Early Pregnancy Unit at University College London Hospital, United Kingdom. PATIENTS: Women with a live pregnancy progressing beyond 12 weeks' gestation and concurrent endometriosis (n = 110) or no endometriosis (n = 393). INTERVENTION: All women underwent a pelvic ultrasound examination in early pregnancy to examine for the presence of endometriosis and uterine abnormalities. MAIN OUTCOME MEASURES: The primary outcome of interest was preterm birth, defined as delivery before 37 completed weeks' gestation. Secondary outcomes included late miscarriage, antepartum hemorrhage, placental site disorders, gestational diabetes, hypertensive disorders of pregnancy, neonates small for gestational age, mode of delivery, intrapartum sepsis, postpartum hemorrhage, and admission to the neonatal unit. RESULTS: Women with a diagnosis of endometriosis did not have statistically significantly higher odds of preterm delivery (adjusted odds ratio [aOR] 1.85 [95% confidence interval {CI} 0.50-6.90]), but they did have higher odds of postpartum hemorrhage during cesarean section (aOR 3.64 [95% CI 2.07-6.35]) and admission of their newborn infant to the neonatal unit (aOR 3.24 [95% CI 1.08-9.73]). Women with persistent or recurrent deep endometriosis after surgery also had higher odds of placental site disorders (aOR 8.65 [95% CI 1.17-63.71]) and intrapartum sepsis (aOR 3.47 [95% CI 1.02-11.75]). CONCLUSION: We observed that women with endometriosis do not have higher odds of preterm delivery, irrespective of their disease subtype. However, they do have higher odds of postpartum hemorrhage during the cesarean section and newborn admission to the neonatal unit.

5.
IEEE Trans Med Robot Bionics ; 6(1): 41-52, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38881728

RESUMEN

In obstetric ultrasound (US) scanning, the learner's ability to mentally build a three-dimensional (3D) map of the fetus from a two-dimensional (2D) US image represents a significant challenge in skill acquisition. We aim to build a US plane localization system for 3D visualization, training, and guidance without integrating additional sensors. This work builds on top of our previous work, which predicts the six-dimensional (6D) pose of arbitrarily oriented US planes slicing the fetal brain with respect to a normalized reference frame using a convolutional neural network (CNN) regression network. Here, we analyze in detail the assumptions of the normalized fetal brain reference frame and quantify its accuracy with respect to the acquisition of transventricular (TV) standard plane (SP) for fetal biometry. We investigate the impact of registration quality in the training and testing data and its subsequent effect on trained models. Finally, we introduce data augmentations and larger training sets that improve the results of our previous work, achieving median errors of 2.97 mm and 6.63° for translation and rotation, respectively.

6.
Exp Physiol ; 109(6): 980-991, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38606906

RESUMEN

Increasing placental perfusion (PP) could improve outcomes of growth-restricted fetuses. One way of increasing PP may be by using phosphodiesterase (PDE)-5 inhibitors, which induce vasodilatation of vascular beds. We used a combination of clinically relevant magnetic resonance imaging (MRI) techniques to characterize the impact that tadalafil infusion has on maternal, placental and fetal circulations. At 116-117 days' gestational age (dGA; term, 150 days), pregnant ewes (n = 6) underwent fetal catheterization surgery. At 120-123 dGA ewes were anaesthetized and MRI scans were performed during three acquisition windows: a basal state and then ∼15-75 min (TAD 1) and ∼75-135 min (TAD 2) post maternal administration (24 mg; intravenous bolus) of tadalafil. Phase contrast MRI and T2 oximetry were used to measure blood flow and oxygen delivery. Placental diffusion and PP were assessed using the Diffusion-Relaxation Combined Imaging for Detailed Placental Evaluation-'DECIDE' technique. Uterine artery (UtA) blood flow when normalized to maternal left ventricular cardiac output (LVCO) was reduced in both TAD periods. DECIDE imaging found no impact of tadalafil on placental diffusivity or fetoplacental blood volume fraction. Maternal-placental blood volume fraction was increased in the TAD 2 period. Fetal D O 2 ${D_{{{\mathrm{O}}_2}}}$ and V ̇ O 2 ${\dot V_{{{\mathrm{O}}_2}}}$ were not affected by maternal tadalafil administration. Maternal tadalafil administration did not increase UtA blood flow and thus may not be an effective vasodilator at the level of the UtAs. The increased maternal-placental blood volume fraction may indicate local vasodilatation of the maternal intervillous space, which may have compensated for the reduced proportion of UtA D O 2 ${D_{{{\mathrm{O}}_2}}}$ .


Asunto(s)
Oxígeno , Placenta , Circulación Placentaria , Tadalafilo , Arteria Uterina , Animales , Femenino , Tadalafilo/farmacología , Tadalafilo/administración & dosificación , Embarazo , Ovinos , Arteria Uterina/efectos de los fármacos , Placenta/efectos de los fármacos , Placenta/irrigación sanguínea , Circulación Placentaria/efectos de los fármacos , Oxígeno/sangre , Flujo Sanguíneo Regional/efectos de los fármacos , Inhibidores de Fosfodiesterasa 5/farmacología , Inhibidores de Fosfodiesterasa 5/administración & dosificación , Imagen por Resonancia Magnética , Feto/irrigación sanguínea , Feto/efectos de los fármacos
7.
Nat Med ; 30(3): 875-887, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38438734

RESUMEN

Isolation of tissue-specific fetal stem cells and derivation of primary organoids is limited to samples obtained from termination of pregnancies, hampering prenatal investigation of fetal development and congenital diseases. Therefore, new patient-specific in vitro models are needed. To this aim, isolation and expansion of fetal stem cells during pregnancy, without the need for tissue samples or reprogramming, would be advantageous. Amniotic fluid (AF) is a source of cells from multiple developing organs. Using single-cell analysis, we characterized the cellular identities present in human AF. We identified and isolated viable epithelial stem/progenitor cells of fetal gastrointestinal, renal and pulmonary origin. Upon culture, these cells formed clonal epithelial organoids, manifesting small intestine, kidney tubule and lung identity. AF organoids exhibit transcriptomic, protein expression and functional features of their tissue of origin. With relevance for prenatal disease modeling, we derived lung organoids from AF and tracheal fluid cells of congenital diaphragmatic hernia fetuses, recapitulating some features of the disease. AF organoids are derived in a timeline compatible with prenatal intervention, potentially allowing investigation of therapeutic tools and regenerative medicine strategies personalized to the fetus at clinically relevant developmental stages.


Asunto(s)
Hernias Diafragmáticas Congénitas , Embarazo , Femenino , Humanos , Hernias Diafragmáticas Congénitas/metabolismo , Líquido Amniótico/metabolismo , Atención Prenatal , Pulmón/metabolismo , Organoides/metabolismo
8.
Biol Reprod ; 110(6): 1065-1076, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38442734

RESUMEN

Although the central role of adequate blood flow and oxygen delivery is known, the lack of optimized imaging modalities to study placental structure has impeded our understanding of its vascular function. Magnetic resonance imaging is increasingly being applied in this field, but gaps in knowledge remain, and further methodological developments are needed. In particular, the ability to distinguish maternal from fetal placental perfusion and the understanding of how individual placental lobules are functioning are lacking. The potential clinical benefits of developing noninvasive tools for the in vivo assessment of blood flow and oxygenation, two key determinants of placental function, are tremendous. Here, we summarize a number of structural and functional magnetic resonance imaging techniques that have been developed and applied in animal models and studies of human pregnancy over the past decade. We discuss the potential applications and limitations of these approaches. Their combination provides a novel source of contrast to allow analysis of placental structure and function at the level of the lobule. We outline the physiological mechanisms of placental T2 and T2* decay and devise a model of how tissue composition affects the observed relaxation properties. We apply this modeling to longitudinal magnetic resonance imaging data obtained from a preclinical pregnant nonhuman primate model to provide initial proof-of-concept data for this methodology, which quantifies oxygen transfer and placental structure across and between lobules. This method has the potential to improve our understanding and clinical management of placental insufficiency once validation in a larger nonhuman primate cohort is complete.


Asunto(s)
Imagen por Resonancia Magnética , Placenta , Animales , Femenino , Embarazo , Imagen por Resonancia Magnética/métodos , Placenta/diagnóstico por imagen , Placenta/fisiología , Primates , Modelos Animales
10.
J Pharm Policy Pract ; 17(1): 2308611, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38333577

RESUMEN

Background: Access to essential malaria commodities is a cornerstone in malaria control. However optimal availability and access to essential malaria commodities remain a challenge in Tanzania. Therefore, this study aimed to explore the factors affecting the accessibility of malaria commodities in Tanzania. Methods: This was a mixed-method cross-sectional study using both quantitative and qualitative approaches. Data were collected between February and March 2023 from health facilities, health facility staff, and patients. Results: Availability of malaria commodities in government health facilities was 100% for all items while in the private and faith-based facilities, this ranged from 10% to 80%. The reasons for stockouts in Government facilities were related to delayed and inadequate quantity delivery while in private facilities the main reason was the lack of cash for procurement. Both private facilities' clients and healthcare providers concurred that most people do not access complete treatment due to the high costs of prescribed medicines and poor stocking levels. Conclusion: The availability, hence the accessibility, of malaria commodities in private and faith-based health facilities is still sub-optimal. Logistic management needs to be improved to eliminate stockouts and malaria commodities high costs need a permanent solution.

11.
Sci Data ; 11(1): 155, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302487

RESUMEN

Urinary tract infection (UTI) is a common disorder. Its diagnosis can be made by microscopic examination of voided urine for markers of infection. This manual technique is technically difficult, time-consuming and prone to inter-observer errors. The application of computer vision to this domain has been slow due to the lack of a clinical image dataset from UTI patients. We present an open dataset containing 300 images and 3,562 manually annotated urinary cells labelled into seven classes of clinically significant cell types. It is an enriched dataset acquired from the unstained and untreated urine of patients with symptomatic UTI using a simple imaging system. We demonstrate that this dataset can be used to train a Patch U-Net, a novel deep learning architecture with a random patch generator to recognise urinary cells. Our hope is, with this dataset, UTI diagnosis will be made possible in nearly all clinical settings by using a simple imaging system which leverages advanced machine learning techniques.


Asunto(s)
Aprendizaje Profundo , Infecciones Urinarias , Humanos , Pruebas Diagnósticas de Rutina , Aprendizaje Automático , Microscopía , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/orina
12.
IEEE Trans Pattern Anal Mach Intell ; 46(5): 3784-3795, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38198270

RESUMEN

Deep learning models for medical image segmentation can fail unexpectedly and spectacularly for pathological cases and images acquired at different centers than training images, with labeling errors that violate expert knowledge. Such errors undermine the trustworthiness of deep learning models for medical image segmentation. Mechanisms for detecting and correcting such failures are essential for safely translating this technology into clinics and are likely to be a requirement of future regulations on artificial intelligence (AI). In this work, we propose a trustworthy AI theoretical framework and a practical system that can augment any backbone AI system using a fallback method and a fail-safe mechanism based on Dempster-Shafer theory. Our approach relies on an actionable definition of trustworthy AI. Our method automatically discards the voxel-level labeling predicted by the backbone AI that violate expert knowledge and relies on a fallback for those voxels. We demonstrate the effectiveness of the proposed trustworthy AI approach on the largest reported annotated dataset of fetal MRI consisting of 540 manually annotated fetal brain 3D T2w MRIs from 13 centers. Our trustworthy AI method improves the robustness of four backbone AI models for fetal brain MRIs acquired across various centers and for fetuses with various brain abnormalities.


Asunto(s)
Algoritmos , Inteligencia Artificial , Imagen por Resonancia Magnética , Feto/diagnóstico por imagen , Encéfalo/diagnóstico por imagen
13.
Materials (Basel) ; 17(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38276430

RESUMEN

Research on perovskites has grown exponentially in the past decade due to the potential of methyl ammonium lead iodide in photovoltaics. Although these devices have achieved remarkable and competitive power conversion efficiency, concerns have been raised regarding the toxicity of lead and its impact on scaling up the technology. Eliminating lead while conserving the performance of photovoltaic devices is a great challenge. To achieve this goal, the research has been expanded to thousands of compounds with similar or loosely related crystal structures and compositions. Some materials are "re-discovered", and some are yet unexplored, but predictions suggest that their potential applications may go beyond photovoltaics, for example, spintronics, photodetection, photocatalysis, and many other areas. This short review aims to present the classification, some current mapping strategies, and advances of lead-free halide double perovskites, their derivatives, lead-free perovskitoid, and low-dimensional related crystals.

14.
Am J Obstet Gynecol MFM ; 6(3): 101298, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38278178

RESUMEN

BACKGROUND: A previous term (≥37 weeks' gestation), full-dilatation cesarean delivery is associated with an increased risk for a subsequent spontaneous preterm birth. The mechanism is unknown. We hypothesized that the cesarean delivery scar characteristics and scar position relative to the internal cervical os may compromise cervical function, thereby leading to shortening of the cervical length and spontaneous preterm birth. OBJECTIVE: This study aimed to determine the relationship of cesarean delivery scar characteristics and position, assessed by transvaginal ultrasound, in pregnant women with previous full-dilatation cesarean delivery with the risk of shortening cervical length and spontaneous preterm birth. STUDY DESIGN: This was a single-center, prospective cohort study of singleton pregnant women (14 to 24 weeks' gestation) with a previous term full-dilatation cesarean delivery who attended a high-risk preterm birth surveillance clinic (2017-2021). Women underwent transvaginal ultrasound assessment of cervical length, cesarean delivery scar distance relative to the internal cervical os, and scar niche parameters using a reproducible transvaginal ultrasound technique. Spontaneous preterm birth prophylactic interventions (vaginal cervical cerclage or vaginal progesterone) were offered for short cervical length (≤25 mm) and to women with a history of spontaneous preterm birth or late miscarriage after full-dilatation cesarean delivery. The primary outcome was spontaneous preterm birth; secondary outcomes included short cervical length and a need for prophylactic interventions. A multivariable logistic regression analysis was used to develop multiparameter models that combined cesarean delivery scar parameters, cervical length, history of full-dilatation cesarean delivery, and maternal characteristics. The predictive performance of models was examined using the area under the receiver operating characteristics curve and the detection rate at various fixed false positive rates. The optimal cutoff for cesarean delivery scar distance to best predict a short cervical length and spontaneous preterm birth was analyzed. RESULTS: Cesarean delivery scars were visualized in 90.5% (220/243) of the included women. The spontaneous preterm birth rate was 4.1% (10/243), and 12.8% (31/243) of women developed a short cervical length. A history- (n=4) or ultrasound-indicated (n=19) cervical cerclage was performed in 23 of 243 (9.5%) women; among those, 2 (8.7%) spontaneously delivered prematurely. A multiparameter model based on absolute scar distance from the internal os best predicted spontaneous preterm birth (area under the receiver operating characteristics curve, 0.73; 95% confidence interval, 0.57-0.89; detection rate of 60% for a fixed 25% false positive rate). Models based on the relative anatomic position of the cesarean delivery scar to the internal os and the cesarean delivery scar position with niche parameters (length, depth, and width) best predicted the development of a short cervical length (area under the receiver operating characteristics curve, 0.79 [95% confidence interval, 0.71-0.87]; and 0.81 [95% confidence interval, 0.73-0.89], respectively; detection rate of 73% at a fixed 25% false positive rate). Spontaneous preterm birth was significantly more likely when the cesarean delivery scar was <5.0 mm above or below the internal os (adjusted odds ratio, 6.87; 95% confidence interval, 1.34-58; P =.035). CONCLUSION: In pregnancies following a full-dilatation cesarean delivery, cesarean delivery scar characteristics and distance from the internal os identified women who were at risk for spontaneous preterm birth and developing short cervical length. Overall, the spontaneous preterm birth rate was low, but it was significantly increased among women with a scar located <5.0 mm above or below the internal cervical os. Shortening of cervical length was strongly associated with a low scar position. Our novel findings indicate that a low cesarean delivery scar can compromise the functional integrity of the internal cervical os, leading to cervical shortening and/or spontaneous preterm birth. Assessment of the cesarean delivery scar characteristics and position seem to have use in preterm birth clinical surveillance among women with a previous, full-dilatation cesarean delivery and could better identify women who would benefit from prophylactic interventions.


Asunto(s)
Nacimiento Prematuro , Recién Nacido , Embarazo , Femenino , Humanos , Nacimiento Prematuro/diagnóstico , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/etiología , Estudios Prospectivos , Cicatriz/etiología , Cicatriz/complicaciones , Dilatación/efectos adversos , Medición de Longitud Cervical/efectos adversos , Medición de Longitud Cervical/métodos
15.
BJOG ; 131(8): 1129-1135, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38247347

RESUMEN

OBJECTIVE: To create a sensorised surgical glove that can accurately identify obstetric anal sphincter injury to facilitate timely repair, reduce complications and aid training. DESIGN: Proof-of-concept. SETTING: Laboratory. SAMPLE: Pig models. METHODS: Flexible triboelectric pressure/force sensors were mounted onto the fingertips of a routine surgical glove. The sensors produce a current when rubbed on materials of different characteristics which can be analysed. A per rectum examination was performed on the intact sphincter of pig cadavers, analogous to routine examination for obstetric anal sphincter injuries postpartum. An anal sphincter defect was created by cutting through the vaginal mucosa and into the external anal sphincter using a scalpel. The sphincter was then re-examined. Data and signals were interpreted. MAIN OUTCOME MEASURES: Sensitivity and specificity of the glove in detecting anal sphincter injury. RESULTS: In all, 200 examinations were performed. The sensors detected anal sphincter injuries in a pig model with sensitivities between 98% and 100% and a specificity of 100%. The current produced when examining an intact sphincter and sphincter with a defect was significantly different (p < 0.001). CONCLUSION: In this preliminary study, the sensorised glove accurately detected anal sphincter injury in a pig model. Future plans include its clinical translation, starting with an in-human study on postpartum women, to determine whether it can accurately detect different types of obstetric anal sphincter injury in vivo.


Asunto(s)
Canal Anal , Guantes Quirúrgicos , Animales , Canal Anal/lesiones , Femenino , Porcinos , Embarazo , Sensibilidad y Especificidad , Modelos Animales de Enfermedad , Laceraciones , Complicaciones del Trabajo de Parto/diagnóstico , Humanos , Prueba de Estudio Conceptual
16.
J Inherit Metab Dis ; 47(1): 192-210, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37470194

RESUMEN

Fetal gene therapy was first proposed toward the end of the 1990s when the field of gene therapy was, to quote the Gartner hype cycle, at its "peak of inflated expectations." Gene therapy was still an immature field but over the ensuing decade, it matured and is now a clinical and market reality. The trajectory of treatment for several genetic diseases is toward earlier intervention. The ability, capacity, and the will to diagnose genetic disease early-in utero-improves day by day. A confluence of clinical trials now signposts a trajectory toward fetal gene therapy. In this review, we recount the history of fetal gene therapy in the context of the broader field, discuss advances in fetal surgery and diagnosis, and explore the full ambit of preclinical gene therapy for inherited metabolic disease.


Asunto(s)
Terapias Fetales , Terapia Genética , Embarazo , Femenino , Humanos
18.
J Thromb Haemost ; 22(2): 455-465, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37926193

RESUMEN

BACKGROUND: Preeclampsia is a gestational hypertensive disorder characterized by maternal endothelial activation and increased ratio of soluble fms-like tyrosine kinase-1 (sFlt-1) inhibitor to placental growth factor (PlGF). The von Willebrand factor (VWF)/ADAMTS-13 axis is of interest because of the underlying endothelial activation and clinical overlap with pregnancy-associated thrombotic thrombocytopenic purpura. OBJECTIVES: To assess VWF, ADAMTS-13, and VWF/ADAMTS-13 ratio in preeclampsia and look for associations with sFlt-1/PlGF ratio and clinical features. METHODS: Thirty-four preeclampsia cases and 48 normal pregnancies were assessed in a case-control study. Twelve normal pregnancies in women with a history of preeclampsia formed an additional comparator group. VWF antigen (VWF:Ag) and VWF activity (VWF:Ac [VWF:glycoprotein IbM]) were measured via automated immunoturbidimetric assay, ADAMTS-13 activity was measured via fluorescence resonance energy transfer-VWF73 assay, and sFlt-1 and PlGF were measured via enzyme-linked immunosorbent assay. RESULTS: VWF:Ag was higher in preeclampsia than in normal pregnancy (median, 3.07 vs 1.87 IU/mL; P < .0001). ADAMTS-13 activity was slightly lower (median, 89.6 vs 94.4 IU/dL; P = .02), with no severe deficiencies. Significant elevations in VWF:Ac were not observed in preeclampsia, resulting in reduced VWF:Ac/VWF:Ag ratios (median, 0.77 vs 0.97; P < .0001). VWF:Ag/ADAMTS-13 ratios were significantly higher in preeclampsia (median, 3.42 vs 2.06; P < .0001), with an adjusted odds ratio of 19.2 for a ratio of >2.7 (>75th centile of normal pregnancy). Those with a history of preeclampsia had similar ratios to normal pregnant controls. VWF:Ag/ADAMTS-13 and sFlt-1/PlGF were not correlated. However, percentage reduction in platelets correlated positively with VWF:Ac (P = .01), VWF:Ac/VWF:Ag ratio (P = .004), and sFlt-1/PlGF ratio (P = .01). CONCLUSION: The VWF/ADAMTS-13 axis is significantly altered in preeclampsia. Further investigation of potential clinical utility is warranted.


Asunto(s)
Preeclampsia , Embarazo , Femenino , Humanos , Factor de Crecimiento Placentario , Preeclampsia/diagnóstico , Factor de von Willebrand , Estudios de Casos y Controles , Proteína ADAMTS13 , Receptor 1 de Factores de Crecimiento Endotelial Vascular , Proteínas Tirosina Quinasas Receptoras , Factor A de Crecimiento Endotelial Vascular , Biomarcadores
19.
Thorax ; 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38050163

RESUMEN

INTRODUCTION: Respiratory syncytial virus (RSV) causes a severe respiratory condition, bronchiolitis, in infants but not in adults. Bronchiolitis is characterised by neutrophilic infiltration in the airways, but whether neutrophils enhance recovery from infection or contribute to its pathology remains unknown. METHODS: We used a novel in-vitro model to compare term umbilical cord blood (infant) (n=17 donors) and adult neutrophils (n=15 donors) during migration across RSV-infected differentiated human nasal airway epithelial cells (AECs) in a basolateral to apical direction. RESULTS: Greater numbers of infant neutrophils (mean (95% CI)) (336 684 (242 352 to 431 015)) migrated across RSV-infected AECs to the apical compartment (equivalent to the airway lumen) compared with adult neutrophils (56 586 (24 954 to 88 218)) (p<0.0001). Having reached the apical compartment of infected AECs, much greater numbers of infant neutrophils (140 787 (103 117 to 178 456)) became apoptotic compared with adult (5853 (444 to 11 261)) (p=0.002). Infant neutrophils displayed much greater expression of CD11b, CD64, neutrophil elastase (NE) and myeloperoxidase (MPO) than adult neutrophils at baseline and at all points of migration. However, as adult neutrophils migrated, expression of CD11b, CD64, NE and MPO became greater than at baseline. DISCUSSION: The high proportion of infant neutrophils migrating across RSV-infected AECs correlates with the neutrophilic infiltrate seen in infants with severe RSV bronchiolitis, with large numbers undergoing apoptosis, which may represent a protective mechanism during infection. Compared with adult neutrophils, infant neutrophils already have high expression of surface markers before contact with AECs or migration, with less capacity to increase further in response to RSV infection or migration.

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