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1.
BMC Pregnancy Childbirth ; 24(1): 431, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879535

RESUMO

OBJECTIVES: To evaluate the potential connections between marginal cord insertion during the first trimester and furcate cord insertion later in pregnancy. METHODS: This is a prospective study of screening data on the cord insertion site in 3178 singleton pregnancies. The cord insertion site was examined in two stages. The first stage was screening for the cord insertion site between 10-13 weeks of gestation, the purpose is to determine the category of umbilical cord insertion. The second stage, performed at 22-28 weeks of gestation, was to follow up on the relationship between the cord insertion site and the placenta and to identify any changes in the category of umbilical cord insertion. This was performed to diagnose or exclude furcate cord insertion by identifying whether the umbilical cord trunk separated or branched before it reached the placenta. Factors influencing progression to furcate cord insertion and perinatal complications were assessed. RESULTS: Fourteen cases (0.44%) with progression to furcate cord insertion, all of which showed marginal cord insertion on ultrasound in the first trimester (p < 0.001). without progression to furcate cord insertion, there were no changes in the category of umbilical cord insertion in 3050 cases (96.40%) compared to the early pregnancy. 114 cases (3.60%) with changes in the category of umbilical cord insertion that was not consistent with furcate cord insertion. A total of 14 cases progressed to furcate cord insertion, all showed the cord insertion site were in close proximity, and 11 (78.57%) cases showed a low insertion site (p < 0.001). Regarding the choice of mode of delivery, elective caesarean delivery was done in 8/14 (57.14%). The incidences of spontaneous vaginal delivery were 5/14 (35.71%) (p < 0.001). One (7.14%) case of progression to furcate cord insertion due to haematoma at the root of the umbilical cord ended with an emergency caesarean section. In terms of perinatal complications, marginal cord insertion that progressed to furcate cord insertion had higher incidences of SGA infants, abnormal placental morphology, retention of the placenta, and cord-related adverse pregnancy outcomes than not progressed to furcate cord insertion (p < 0.05). CONCLUSIONS: Marginal cord insertion in the first trimester has the potential to progress to furcate cord insertion. We suggest that ultrasound-diagnosed marginal cord insertion in the first trimester should be watched carefully in the second trimester, which is clinically useful to accurately determine the category of cord insertion and to improve the rate of prenatal diagnosis of furcate cord insertion.


Assuntos
Primeiro Trimestre da Gravidez , Ultrassonografia Pré-Natal , Cordão Umbilical , Humanos , Gravidez , Feminino , Cordão Umbilical/diagnóstico por imagem , Cordão Umbilical/anatomia & histologia , Estudos Prospectivos , Adulto , Placenta/diagnóstico por imagem , Idade Gestacional , Recém-Nascido
2.
Med Image Anal ; 97: 103229, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38897033

RESUMO

Arrhythmia is a major cardiac abnormality in fetuses. Therefore, early diagnosis of arrhythmia is clinically crucial. Pulsed-wave Doppler ultrasound is a commonly used diagnostic tool for fetal arrhythmia. Its key step for diagnosis involves identifying adjacent measurable cardiac cycles (MCCs). As cardiac activity is complex and the experience of sonographers is often varied, automation can improve user-independence and diagnostic-validity. However, arrhythmias pose several challenges for automation because of complex waveform variations, which can cause major localization bias and missed or false detection of MCCs. Filtering out non-MCC anomalies is difficult because of large intra-class and small inter-class variations between MCCs and non-MCCs caused by agnostic morphological waveform variations. Moreover, rare arrhythmia cases are insufficient for classification algorithms to adequately learn discriminative features. Using only normal cases for training, we propose a novel hierarchical online contrastive anomaly detection (HOCAD) framework for arrhythmia diagnosis during test time. The contribution of this study is three-fold. First, we develop a coarse-to-fine framework inspired by hierarchical diagnostic logic, which can refine localization and avoid missed detection of MCCs. Second, we propose an online learning-based contrastive anomaly detection with two new anomaly scores, which can adaptively filter out non-MCC anomalies on a single image during testing. With these complementary efforts, we precisely determine MCCs for correct measurements and diagnosis. Third, to the best of our knowledge, this is the first reported study investigating intelligent diagnosis of fetal arrhythmia on a large-scale and multi-center ultrasound dataset. Extensive experiments on 3850 cases, including 266 cases covering three typical types of arrhythmias, demonstrate the effectiveness of the proposed framework.

3.
Heart Rhythm ; 21(5): 600-609, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38266752

RESUMO

BACKGROUND: The motion relationship and time intervals of the pulsed-wave Doppler (PWD) spectrum are essential for diagnosing fetal arrhythmia. However, few technologies currently are available to automatically calculate fetal cardiac time intervals (CTIs). OBJECTIVE: The purpose of this study was to develop a fetal heart rhythm intelligent quantification system (HR-IQS) for the automatic extraction of CTIs and establish the normal reference range for fetal CTIs. METHODS: A total of 6498 PWD spectrums of 2630 fetuses over the junction between the left ventricular inflow and outflow tracts were recorded across 14 centers. E, A, and V waves were manually labeled by 3 experienced fetal cardiologists, with 17 CTIs extracted. Five-fold cross-validation was performed for training and testing of the deep learning model. Agreement between the manual and HR-IQS-based values was evaluated using the intraclass correlation coefficient and Spearman's rank correlation coefficient. The Jarque-Bera test was applied to evaluate the normality of CTIs' distributions, and the normal reference range of 17 CTIs was established with quantile regression. Arrhythmia subset was compared with the non-arrhythmia subset using the Mann-Whitney U test. RESULTS: Significant positive correlation (P <.001) and moderate-to-excellent consistency (P <.001) between the manual and HR-IQS automated measurements of CTIs was found. The distribution of CTIs was non-normal (P <.001). The normal range (2.5th to 97.5th percentiles) was successfully established for the 17 CTIs. CONCLUSIONS: Using our HR-IQS is feasible for the automated calculation of CTIs in practice and thus could provide a promising tool for the assessment of fetal rhythm and function.


Assuntos
Arritmias Cardíacas , Coração Fetal , Frequência Cardíaca Fetal , Humanos , Feminino , Estudos Prospectivos , Gravidez , Frequência Cardíaca Fetal/fisiologia , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Coração Fetal/diagnóstico por imagem , Coração Fetal/fisiologia , Idade Gestacional , Ultrassonografia Pré-Natal/métodos
4.
Zhongguo Gu Shang ; 35(7): 605-9, 2022 Jul 25.
Artigo em Zh | MEDLINE | ID: mdl-35859367

RESUMO

OBJECTIVE: To explore the effect of personalized digital analog assisted acetabular prosthesis precise implantation in hip dysplasia. METHODS: From February 2017 to July 2019, 11 patients(12 hips) with hip dysplasia underwent total hip arthroplasty, including 4 males(5 hips) and 7 females(7 hips), aged from 27 to 61 years old, with an average of (46.64±12.93) years old;Crowe classification:8 hips in typeⅠ and 4 hips in typeⅡ. The preoperative thin-layer CT scan was imported into Mimics 10.01 software. The appropriate size and placement angle of acetabular prosthesis were selected through preoperative simulation, and the acetabular bone defect was understood to determine whether structural bone grafting was needed during the operation. The length of both lower limbs, the anteversion angle of acetabular prosthesis, the abduction angle, the height of acetabular rotation center and the horizontal distance of hip joint center before and after the operation were measured, and the postoperative dislocation, bone graft healing and acetabular cup loosening were observed. The hip Harris score was used to evaluate the joint function. RESULTS: All patients were followed up for 18 to 30 months with an average of (23.45±3.70) months. There was no prosthesis dislocation, loosening and bone graft healing after operation. One case had numbness in the innervation area due to the traction of sciatic nerve during operation, and was treated with neurotrophic drugs and recovered one month after operation. The length difference of both lower limbs decreased from (31.73±5.98) mm before operation to (4.73±1.90) mm 3 months after operation (t=15.268, P<0.01). The anteversion angle of acetabular cup and acetabulum was (17.45±3.62)°and abduction angle was (40.10 ± 2.30)° after operation. In all cases, the abduction angle and anteversion angle were within the safe range of Lewinek. The height of hip rotation center was (20.64±2.58) mm and the horizontal inward displacement of hip was (33.46±3.61) mm. Harris score increased from (45.36±2.34) before operation to (91.27±2.37) 3 months after operation (P<0.05). CONCLUSION: Through preoperative personalized digital analog reconstruction of acetabulum in patients with hip dysplasia, we can better understand the acetabular defect, help to evaluate the size and placement angle of acetabular prosthesis and whether structural bone grafting is needed, and obtain satisfactory clinical curative effect.


Assuntos
Artroplastia de Quadril , Luxação do Quadril , Prótese de Quadril , Acetábulo/cirurgia , Adulto , Feminino , Seguimentos , Luxação do Quadril/cirurgia , Luxação Congênita de Quadril/cirurgia , Humanos , Luxações Articulares/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
5.
Chemphyschem ; 11(13): 2764-78, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20718064

RESUMO

The last decade has witnessed remarkable advances in interfacial electrochemistry in room-temperature ionic liquids. Although the wide electrochemical window of ionic liquids is of primary concern in this new type of solvent for electrochemistry, the unusual bulk and interfacial properties brought about by the intrinsic strong interactions in the ionic liquid system also substantially influence the structure and processes at electrode/ionic liquid interfaces. Theoretical modeling and experimental characterizations have been indispensable in reaching a microscopic understanding of electrode/ionic liquid interfaces and in elucidating the physics behind new phenomena in ionic liquids. This Minireview describes the status of some aspects of interfacial electrochemistry in ionic liquids. Emphasis is placed on high-resolution and molecular-level characterization by scanning tunneling microscopy and vibrational spectroscopies of interfacial structures, and the initial stage of metal electrodeposition with application in surface nanostructuring.


Assuntos
Líquidos Iônicos/química , Nanopartículas Metálicas/química , Metais/química , Adsorção , Eletroquímica , Eletrodos , Propriedades de Superfície
6.
J Am Chem Soc ; 131(41): 14728-37, 2009 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-19778042

RESUMO

Neutral inorganic molecules are generally weak in surface adsorption and intermolecular interactions. Self-assembly of such types of molecule would provide valuable information about various interactions. At electrochemical interfaces, the relative strength of these interactions may be modified through control of electrode potential and electrolyte, which may lead to the discovery of new structures and new phenomena. However, studies of this nature are as yet lacking. In this work, we consider the covalent-bound semimetal compound molecules, XCl(3) (X = Sb, Bi), as model systems of neutral inorganic molecules to investigate their self-assembly at electrochemical interfaces under a high ionic atmosphere. To fulfill such investigations, in situ STM and cyclic voltammetry are employed, and comparative experiments are performed on Au(111) in ionic liquids as well as aqueous solutions with high ionic strength. In the room temperature ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIBF(4)), potential-dependent partial charge transfer between the Au surface and XCl(3) molecules creates a molecule-surface interaction and provides the driving force for adsorption of the molecules. Supramolecular aggregations of adsorbed XCl(3) are promoted through chlorine-based short-range intermolecular correlation under crystallographic constraint, while repulsive Coulombic interactions created between the partially charged aggregations facilitate their long-range ordering. For SbCl(3) molecules, hexagonally arranged 6- or 7-member clusters are formed at 0.08 to -0.2 V (vs Pt), which assemble into a secondary ( radical31 x radical31)R8.9 degrees structure. For BiCl(3) molecules, both the 6-membered hexagonal and 3-membered trigonal clusters are formed in the narrow potential range -0.3 to -0.35 V, and are also arranged into an ordered secondary structure. Comparative studies were performed with SbCl(3) in concentrated aqueous solutions containing 2 M HCl to simulate the strong ionic strength of the ionic liquid. Almost identical 6-/7-member clusters and long-range ( radical31 x radical31)R8.9 degrees structure are observed at -0.1 V, demonstrating the crucial role of strong ionic strength in such supramolecular aggregations. However, such supramolecular structures are modified and eventually destroyed as ionic strength is further increased by addition of NaClO(4) up to 6 M. The destructive changes of the supramolecular structures are attributed to the alteration of ion distribution in the double layer from cation-rich to anion-rich at increasing NaClO(4) concentration. This modifies and eventually breaks the balance of intermolecular and molecule-electrolyte interactions. Finally, the dynamic behavior of the SbCl(3) assembly is investigated down to molecular level. It has been demonstrated that the initial stage of assembly follows a two-dimensional nucleation and growth mechanism and has a potential-dependent rate that is closely related to the surface mobility of the SbCl(3) clusters. There is a probability that clusters can escape from an existing assembly domain or insert into a vacancy in such a domain while they can also relax with central or ring members in a dynamic fashion. These phenomena indirectly reflect the dynamic properties of cations from electrolytes at the interface. The rich information contained in the self-assembly behavior of SbCl(3) and BiCl(3) demonstrates that neutral inorganic molecules can be employed for fundamental studies of a variety of interesting issues, especially the interplay of various interfacial interactions.

7.
Angew Chem Int Ed Engl ; 48(28): 5148-51, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19526471

RESUMO

Ring any bells? The differential capacitance curve of Au(100) in neat [BMI]BF(4) (BMI = 1-butyl-3-methylimidazolium) ionic liquid has a bell-shaped feature (see picture). The adsorption of BMI(+) shows a disorder-order transition and depends on the structure of the surface. Ordered adsorption in a micelle-like structure stabilizes the underlying Au surface.


Assuntos
Ouro/química , Imidazóis/química , Líquidos Iônicos/química , Adsorção , Eletrodos , Micelas , Propriedades de Superfície
8.
Clin Hemorheol Microcirc ; 73(4): 545-552, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31306113

RESUMO

OBJECTIVE: To analyze the association of BRAFV600E mutation with ultrasonographic (US) features and clinicopathologic characteristics in Chinese patients with papillary thyroid microcarcinoma (PTMC). METHODS AND MATERIALS: We retrospectively reviewed 116 consecutive Chinese patients with PTMC diagnosed by postoperative pathology. The incidence of the BRAFV600E mutation was calculated. The US features and clinicopathologic characteristics were compared between BRAF-positive and BRAF-negative patients. RESULTS: The BRAFV600E mutation was detected in 60.3% of patients (70 of 116). Multifocality (OR: 3.681, P = 0.031), non-parallel orientation (OR: 3.181, P = 0.041) and lymph node metastasis (OR: 4.615, P = 0.009) were significantly associated with BRAFV600E mutation. Other US and clinicopathologic characteristics were not significantly related to the presence of BRAF mutation. CONCLUSION: Multifocality, non-parallel orientation and cervical lymph node metastasis are risk factors for BRAFV600E mutation in PTMC. These factors potentially guide treatment planning or prognosis evaluation.


Assuntos
Carcinoma Papilar/diagnóstico por imagem , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Feminino , Humanos , Masculino , Mutação , Prognóstico , Estudos Retrospectivos , Fatores de Risco
9.
Cancer Manag Res ; 11: 7211-7217, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440100

RESUMO

Background: Prophylactic central lymph node dissection (CLND) in papillary thyroid microcarcinoma (PTMC) patients without clinical evidence of central lymph node metastasis (CLNM) remains controversial. The purpose of our study is to identify preoperative predictive factors for finding CLNM in Chinese PTMC patients, which may allow tailored CLND. Methods: We retrospectively reviewed 182 consecutive Chinese PMTC patients with negative central lymph nodes who underwent total thyroidectomy plus central neck dissection from October 2015 to December 2017. Chi-squared and multivariate analysis were performed to evaluate the association of CLNM with ultrasonographic and clinicopathologic characteristics. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the utility of markers in predicting CLNM. Results: The CLNM was found in 39.0% (71 of 182) of cN0 PTMC patients. In multivariate analysis, tumor size>7 mm (OR: 3.636, 95% CI: 1.671-7.914), marked hypoechogenicity (OR: 2.686, 95% CI: 1.080-6.678), multifocality (OR: 4.184, 95% CI: 1.707-10.258) and BRAFV600E mutation (OR: 5.339, 95% CI: 2.529-11.272) were independent predictors of CLNM. In ROC analysis integrating these predictors, the sensitivity was 63.4% and specificity was 80.2%, and the area under the ROC (AUC) was 0.755. Conclusion: In conclusion, we found tumor size>7 mm, marked hypoechogenicity, multifocality, and BRAFV600E mutation were risk factors for CLNM. In term of these preoperative risk factors for CLNM, prophylactic CLND should be cautiously performed in cN0 PTMC patients.

10.
Chem Commun (Camb) ; 48(4): 582-4, 2012 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-22109542

RESUMO

High quality AFM force curves are presented with detailed potential dependent layering behaviors of the ionic liquid molecules, from which charged interior and neutral exterior layers are distinguished. The electric double layer is confined within the interior layers of one to two molecular size within the potential range of up to 1 V negative of the PZC.

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