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In vitro fertilization (IVF) has revolutionized infertility treatment, benefiting millions of couples worldwide. However, current clinical practices for embryo selection rely heavily on visual inspection of morphology, which is highly variable and experience dependent. Here, we propose a comprehensive artificial intelligence (AI) system that can interpret embryo-developmental knowledge encoded in vast unlabeled multi-modal datasets and provide personalized embryo selection. This AI platform consists of a transformer-based network backbone named IVFormer and a self-supervised learning framework, VTCLR (visual-temporal contrastive learning of representations), for training multi-modal embryo representations pre-trained on large and unlabeled data. When evaluated on clinical scenarios covering the entire IVF cycle, our pre-trained AI model demonstrates accurate and reliable performance on euploidy ranking and live-birth occurrence prediction. For AI vs. physician for euploidy ranking, our model achieved superior performance across all score categories. The results demonstrate the potential of the AI system as a non-invasive, efficient, and cost-effective tool to improve embryo selection and IVF outcomes.
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OBJECTIVES: Although many prognostic factors in neonates with congenital diaphragmatic hernia (CDH) have been described, no consensus thus far has been reached on which and how many factors are involved. The aim of this study is to analyze the association of multiple prenatal and postnatal factors with 1-month mortality of neonates with CDH and to construct a nomogram prediction model based on significant factors. METHODS: A retrospective analysis of neonates with CDH at our center from 2013 to 2022 was conducted. The primary outcome was 1-month mortality. All study variables were obtained either prenatally or on the first day of life. Risk for 1-month mortality of CDH was quantified by odds ratio (OR) with 95% confidence interval (CI) in multivariable logistic regression models. RESULTS: After graded multivariable adjustment, six factors were found to be independently and consistently associated with the significant risk of 1-month mortality in neonates with CDH, including gestational age of prenatal diagnosis (OR, 95% CI, P value: 0.845, 0.772 to 0.925, < 0.001), observed-to-expected lung-to-head ratio (0.907, 0.873 to 0.943, < 0.001), liver herniation (3.226, 1.361 to 7.648, 0.008), severity of pulmonary hypertension (6.170, 2.678 to 14.217, < 0.001), diameter of defect (1.560, 1.084 to 2.245, 0.017), and oxygen index (6.298, 3.383 to 11.724, < 0.001). Based on six significant factors identified, a nomogram model was constructed to predict the risk for 1-month mortality in neonates with CDH, and this model had decent prediction accuracy as reflected by the C-index of 94.42%. CONCLUSIONS: Our findings provide evidence for the association of six preoperational and intraoperative factors with the risk of 1-month mortality in neonates with CDH, and this association was reinforced in a nomogram model.
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Hérnias Diafragmáticas Congênitas , Nomogramas , Humanos , Hérnias Diafragmáticas Congênitas/mortalidade , Recém-Nascido , Estudos Retrospectivos , Feminino , Masculino , Prognóstico , Idade Gestacional , Mortalidade Infantil/tendências , Fatores de Risco , Medição de Risco/métodosRESUMO
A protocol for trans-hydroboration of indole derivatives using heterogeneous photocatalysis with NHC-borane has been developed, addressing a persistent challenge in organic synthesis. The protocol, leveraging high crystalline vacancy-engineered polymeric carbon nitride as a catalyst, enables diastereoselective synthesis, expanding substrate scope and complementing existing methods. The approach emphasizes eco-friendliness, cost-effectiveness, and scalability, making it suitable for industrial applications, particularly in renewable energy contexts. The catalyst's superior performance, attributed to its rich carbon-vacancies and well-ordered structure, surpasses more expensive homogeneous alternatives, enhancing viability for large-scale use. This innovation holds promise for synthesizing bioactive compounds and materials relevant to medicinal chemistry and beyond.
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A family of titanium complexes (Ti1-Ti7) with the general formula LTiCl3, supported by tridentate phenoxyimine [O-NO] ligands (L1-L7) bearing bulky sidearms, were synthesized by treating the corresponding ligands with stoichiometric amount of TiCl4. All the ligands and complexes were well characterized by 1H and 13C NMR spectroscopies, in which ortho- methoxyl groups on N-aryl moieties shifted to downfield, corroborating the successful coordination reaction. Structural optimization by DFT calculations revealed that one of the phenyl groups on dibenzhydryl moiety could form π-π stacking interaction with the salicylaldimine plane, because of which the obtained titanium complexes revealed good thermal stabilities for high-temperature polymerization of ethylene. The thermal robustness of the complexes was closely related to the strength of π-π stacking interactions, which were mainly influenced by the substituents on the dibenzhydryl moieties; Ti1, Ti4 and Ti5 emerged as the three best-performing complexes at 110 °C. With the aid of such π-π stacking interactions, the complexes were also found to be active at >150 °C, although decreased activities were witnessed. Besides homopolymerizations, complexes Ti1-Ti7 were also found to be active for the high-temperature copolymerization of ethylene and 1-octene, but with medium incorporation percentage, demonstrating their medium copolymerization capabilities.
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Electron donor-acceptor (EDA) complex photochemistry has emerged as a vibrant area in visible-light-mediated synthetic radical chemistry. However, theoretical insights into the reaction mechanisms remain limited. Our study investigates the influence of solvent polarity and halogen atom types on radical reaction pathways in EDA complexes. We demonstrate that solvent polarity modulates the charge transfer and spatial arrangement within EDA complexes, thereby influencing their stability and reaction kinetics. Iodide ions play a crucial role in facilitating free radical generation and stabilizing reaction intermediates. Different halogen atom types exhibit distinct effects on radical reactions. Variations in radical concentration and solvent environment further affect the pathway selectivity. Additionally, light conditions influence the free radical generation and pathway selectivity. Our findings enhance the understanding of EDA complex photochemistry and radical reactions, offering insights for organic synthesis and photochemistry applications.
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Support effect is an important issue in heterogeneous catalysis, while the explicit role of a catalytic support is often unclear for catalytic reactions. A systematic density functional theory computational study is reported in this paper to elucidate the effect of a model boron nitride (BN) support on the first N-H bond activation step of NH3 on Run (n = 1, 2, 3) metal clusters. Geometry optimizations and energy calculations were carried out using density functional theory (DFT) calculation for intermediates and transition states from the starting materials undergoing the N-H activation process. The primary findings are summarized as follows. The involvement of the model BN support does not significantly alter the equilibrium structure of intermediates and transition states in the most favorable pathway (MFP). Moreover, the involvement of BN support decreases the free energy of activation, ΔG≠, thus improving the reaction rate constant. This improvement is more obvious at high temperatures like 673 K than low temperatures like 298 K. The BN support effect leading to the ΔG≠ decrease is most significant for the single Ru atom case among all three cases studied. Finally, the involvement of the model BN may change the spin transition behavior of the reaction system during the N-H bond activation process. All these findings provide a deeper insight into the support effect on the N-H bond activation of NH3 for the supported Ru catalyst in particular and for supported transition metal catalysts in general.
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Adsorptive desulfurization (ADS) was a hopeful method for deep desulfurization of oil in mild conditions. In this paper, based on the alkaline-earth (AE) metal-modified Y zeolite (AEY), synthesis, systematic characterization, ADS performance test, and analysis of related adsorption mechanisms were carried out. The crystal and pore structure of Y zeolite were not damaged after ion exchange of AE, while the amount of acid sites and the ratio of Lewis/Bronsted acid sites were both decreased. Although surface acid sites on zeolites were believed to be active sites for ADS, the performance test results showed that AEY adsorbents had rather good S adsorption capacity compared to NaY. Moreover, the S adsorption selectivity in the presence of hexene-1 in oil was also desirable for all AEY adsorbents. Based on these experimental results and previously proposed mechanisms for S-containing compound adsorption, a new adsorption mechanism was proposed for AEY, and this mechanism was further supported by the aid of DFT calculations. The good S-removal performance of AEY adsorbents as well as the new proposed adsorption mechanism may help people design and synthesize further improved S-compound adsorbents for ADS processes in an oil refinery.
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The adsorption of methanethiol (MT), thiophene (T), benzothiophene (BT), dibenzothiophene (DBT) on hexagonal boron nitride (h-BN) has been investigated by the framework of the density functional theory (DFT) calculations in this work. The prefer adsorption sites and interfacial angles of different sulfur compounds on the surface of the h-BN are investigated and analyzed. The adsorption energy results indicated that the adsorption of MT (Ead ≈ -6 kcal mol-1), T (Ead ≈ -10 kcal mol-1), BT (Ead ≈ -15 kcal mol-1), and DBT (Ead ≈ -21 kcal mol-1) on monolayer h-BN is physical interaction, and the value of Ead on bilayer h-BN is more than that on monolayer h-BN 0.05%. Adsorptive conformations show that sulfides prefer to be adsorbed on center B atoms rather than N atoms. Meanwhile, thiophene and its analogues tend to be adsorbed parallel on h-BN plane. Energy decomposition, natural population analysis (NPA), and electrostatic potential (ESP) analysis used to better understand the nature of adsorption on h-BN. van der Waals force plays a dominant role in adsorption process. Due to the π-π interactions, T, BT, and DBT have larger van der Waals forces than MT and the value of adsorption energy is negative correlated to the number of benzene rings. These findings are helpful for deeper understanding the adsorptive desulfurization mechanism and help develop better adsorbents for desulfurization in the future.
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Objective: To evaluate whether the patent ductus arteriosus (PDA) can serve as a predictive factor for inpatient outcomes in congenital diaphragmatic hernia (CDH) patients. Methods: A retrospective cohort study was conducted on 59 CDH patients at the Capital Institute of Pediatrics from January 2020 to August 2022. Echocardiography was performed at least three times: within 2-3â h after birth, pre-operatively, and post-operatively of CDH surgery. Based on the direction of the PDA shunt in the first echocardiogram, patients were classified into three groups: left-to-right shunting or closed PDA (L-R), bi-directional shunting, and right-to-left shunting (R-L). Results: The mortality rate was 15.3% (9/59), with all non-survivors having R-L shunting and group mortality of 39.1% (9/23). The direction of the PDA shunt was significantly associated with the duration of ventilation and length of hospital stay (p < 0.05). Decreased PDA diameter or pre-operative shunting direction change towards L-R or bi-directional shunting were associated with higher survival rates, while increased PDA diameter or continuous R-L shunting were associated with higher mortality rates. Pre-operative PDA shunt direction, PDA size after birth and before surgery, gestational age of diagnosis, and shortening fraction before surgery were significantly correlated with patient outcomes. The direction of the preoperative PDA shunt was the most relevant factor among these relationships (p = 0.009, OR 20.6, CI 2.2â¼196.1). Conclusion: Our findings highlight the importance of monitoring changes in PDA shunt directionality and diameter in the early stage after birth, as these parameters may serve as valuable predictors of patient outcomes.
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BACKGROUND: Idiopathic pulmonary fibrosis (IPF) bears high mortality due to unclear pathogenesis and limited therapeutic options. Therefore, identifying novel regulators is required to develop alternative therapeutic strategies. METHODS: The lung fibroblasts from IPF patients and Reticulocalbin 3 (RCN3) fibroblast-selective knockdown mouse model were used to determine the importance of Rcn3 in IPF; the epigenetic analysis and protein interaction assays, including BioID, were used for mechanistic studies. RESULTS: Reticulocalbin 3 (RCN3) upregulation is associated with the fibrotic activation of lung fibroblasts from IPF patients and Rcn3 overexpression blunts the antifibrotic effects of pirfenidone and nintedanib. Moreover, repressing Rcn3 expression in mouse fibroblasts ameliorates bleomycin-induced lung fibrosis and pulmonary dysfunction in vivo. Mechanistically, RCN3 promotes fibroblast activation by maintaining persistent activation of TGFß1 signalling via the TGFß1-RCN3-TGFBR1 positive feedback loop, in which RCN3 upregulated by TGFß1 exposure detains EZH2 (an epigenetic methyltransferase) in the cytoplasm through RCN3-EZH2 interaction, leading to the release of the EZH2-H3K27me3 epigenetic repression of TGFBR1 and the persistent expression of TGFBR1. CONCLUSIONS: These findings introduce a novel regulating mechanism of TGFß1 signalling in fibroblasts and uncover a critical role of the RCN3-mediated loop in lung fibrosis. RCN3 upregulation may cause resistance to IPF treatment and targeting RCN3 could be a novel approach to ameliorate pulmonary fibrosis.
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Fibrose Pulmonar Idiopática , Animais , Camundongos , Receptor do Fator de Crescimento Transformador beta Tipo I , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Bleomicina/toxicidade , Modelos Animais de Doenças , Fibroblastos , Proteínas de Ligação ao CálcioRESUMO
Ultrafast microchannel plate (MCP) photomultiplier tubes are under active development. To obtain high gain, high spatial resolution, and good time performance, we comprehensively investigate the effects of the gap distances and voltages from cathode to MCPin and MCPout to anode in a systematic study using the finite integral technique and Monte Carlo method. A three-dimensional model is introduced to simplify the calculations. From the simulation results, a short gap distance and high gap voltage were determined to achieve good time performance, high spatial resolution, and high gain.
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The catalytic acceptorless dehydrogenation (ADH) of saturated N-heterocycles has recently gained considerable attention as a promising strategy for hydrogen release from liquid organic hydrogen carriers (LOHCs). Recently, a simple tBuOK base-promoted ADH of N-heterocycles was developed by Yu et al. (Adv. Synth. Catal. 2019, 361, 3958). However, it is still open as to how the tBuOK plays a catalytic role in the ADH process. Herein, our density functional study reveals that the tBuOK catalyzes the ADH of 1,2,3,4-tetrahydroquinoline (THQ) through a quasi-metal-ligand bifunctional catalytic channel or a base-catalyzed pathway with close energy barriers. The hydride transfer in the first dehydrogenation process is determined to be the rate determining step, and the second dehydrogenation can proceed directly from 34DHQ regulated by the tBuOK. In addition, the computational results show that the cooperation of a suitable alkali metal ion with the tBuO- group is so critical that the tBuOLi and the isolated tBuO- are both inferior to tBuOK as a dehydrogenation catalyst.
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BACKGROUND: Fetal atrial flutter (AF), accounting for 30% of all fetal tachyarrhythmias, predominantly (over 80%) manifests as a 2:1 atrioventricular conduction. Swift referral and timely intervention become imperative in instances of severe persistent arrhythmia. CASE PRESENTATION: We discuss the case of a 32-year-old multiparous Chinese woman, at 30+2 weeks of gestation, wherein an ultrasonographic examination revealed persistent fetal AF (atrial rate ranging from 219 to 445 beats/min and ventricular rate from 219 to 228 beats/min, with a 2:1 or 1:1 down transmission) and minor ascites. Despite the maternal ingestion of digoxin and sotalol, the fetal heart rhythm remained uncorrected. Following this, at 32+3 weeks of gestation, an intramuscular injection of cedilanid, guided by ultrasound, was administered to the fetus. Postoperatively, the fetal ventricular rate demonstrated a decline after 6 days, and the ascites resolved. Subsequently, at 33+3 weeks, a cesarean section was necessitated due to maternal intolerance to the medication, resulting in the delivery of the infant. Remarkably, the infant's cardiac rhythm spontaneously converted to sinus rhythm within 5 min of birth. A follow-up conducted 1 year postpartum revealed no recurrence of AF. CONCLUSIONS: This case illustrates that in the event of transplacental drug treatment failure, intrauterine therapeutic intervention should be considered. Moreover, it highlights the encouraging prognosis associated with fetal AF, as the cardiac rhythm spontaneously reverted to sinus rhythm postbirth in this instance.
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Flutter Atrial , Doenças Fetais , Gravidez , Humanos , Feminino , Adulto , Flutter Atrial/tratamento farmacológico , Flutter Atrial/complicações , Flutter Atrial/diagnóstico , Antiarrítmicos/uso terapêutico , Cesárea , Ascite/complicações , Ascite/tratamento farmacológico , Doenças Fetais/tratamento farmacológico , Arritmias Cardíacas/complicações , Arritmias Cardíacas/tratamento farmacológico , FetoRESUMO
Objective: The aim of this study was to explore the symptoms, treatment, and pathogenesis of ovarian juvenile granulosa cell tumors with Ollier's disease in children. Methods: From October 2019 to October 2020, clinical data were retrospectively analyzed for one case of ovarian juvenile granulosa cell tumors with Ollier's disease. Whole-exome sequencing and Sanger sequencing were used to detect gene mutation in ovarian tumor and chondroma tissue. NADP-dependent isocitrate dehydrogenase-1 (IDH1) and S6 ribosomal protein expression levels in cells transfected with wild-type or mutant plasmid were analyzed by Western blot. Results: The 4-year-old female showed multiple skeletal deformities, bilateral breast development with chromatosis, and vulvar discharge. Sex hormone assay suggested that estradiol and prolactin were elevated, and the x-ray of limbs suggested enchondroma. Pelvic ultrasound and abdominal CT revealed a right ovarian solid mass. Pathologic examination of the right ovarian solid mass showed a juvenile granulosa cell type. A c.394C>T (p. Arg132Cys) mutation of the IDH1 gene was detected in both the ovarian juvenile granulosa cell tumors and enchondroma. Transfection of HeLa cells with either WT or Mut plasmid caused 4.46- or 3.77-fold overexpression of IDH1 gene compared to non-transfected control cells, respectively. R132C mutation inhibited the phosphorylation of S6 ribosomal protein, which is central to the mTOR pathway. Postoperatively, estradiol and prolactin levels fell to values normal for her age and bilateral breast gradual retraction. Conclusion: The incidence of ovarian juvenile granulosa cell tumors with Ollier's disease in children may be caused by generalized mesodermal dysplasia; IDH1 gene mutation may play a facilitated role in this process. Surgical operation is the main treatment. We suggest that patients with ovarian juvenile granulosa cell tumors and Ollier's disease should undergo regular investigation.
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Encondromatose , Tumor de Células da Granulosa , Humanos , Criança , Feminino , Pré-Escolar , Encondromatose/genética , Tumor de Células da Granulosa/genética , Tumor de Células da Granulosa/patologia , Células HeLa , Prolactina , Estudos Retrospectivos , Proteínas Ribossômicas , Estradiol , Isocitrato DesidrogenaseRESUMO
BACKGROUND: No study has reported on the relationship between the vasoactive-inotropic score (VIS) and the prognosis of neonates with a severe congenital diaphragmatic hernia (CDH). This study aimed to identify potential risk factors for mortality in patients with CDH. We calculated the VIS based on the vasoactive drugs used during the perioperative period to investigate the relationship between VIS and infant prognosis. METHODS: We retrospectively analyzed the clinical data of 75 neonates with CDH who were treated at our center between January 2016 and October 2021. We calculated the maximum and mean VIS during the first 24 h of hospitalization (hosVIS [24max] and hosVIS [24mean], respectively) and after surgery (postVIS [24max] and postVIS [24mean], respectively). The relationship between the VIS and the prognosis of neonates with CDH was analyzed using a receiver operating characteristic (ROC) curve, t-test, chi-square test, rank-sum test, and logistic regression analysis. RESULTS: In total, 75 participants with CDH were included in the study. The chance of survival was 80%. Our results showed that hosVIS (24max) was an accurate predictor of prognosis (area under the ROC curve = 0.925, p = 0.007). The calculated optimal critical value of hosVIS (24max) for predicting a poor prognosis was 17 (J = 0.75). Multivariate analysis revealed that hosVIS (24max) was an independent risk factor for death in neonates with CDH. CONCLUSION: In neonates with CDH, a higher VIS, especially hosVIS (24max), suggests worsened cardiac function, a more severe condition, and a higher risk of death. The rising VIS score in infants prompts physicians to implement more aggressive treatment to improve cardiovascular function.
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Hérnias Diafragmáticas Congênitas , Recém-Nascido , Lactente , Humanos , Hérnias Diafragmáticas Congênitas/diagnóstico , Hérnias Diafragmáticas Congênitas/cirurgia , Estudos Retrospectivos , Prognóstico , Curva ROC , HospitalizaçãoRESUMO
Objective: Previous studies have shown that ex utero intrapartum therapy (EXIT) is safe and feasible for newborns with congenital diaphragmatic hernia (CDH). This study reports our experience with EXIT in fetuses with CDH in an attempt to explore the efficacy of EXIT on the survival rate of this population. Methods: A retrospective analysis of the clinical data of 116 children with CDH was conducted. The children were assigned to EXIT and non-EXIT groups. Propensity score matching (PSM) toward clinical data was performed, and the clinical characteristics and outcomes were compared. Taking survival at discharge as the main outcome, logistic regression analysis was carried out to explore the efficacy of EXIT on survival. Results: During the study period, 30 of 116 children received EXIT. After PSM, the survival rates of the EXIT group and the non-EXIT group were 82.76% (24/29) and 48.28% (14/29), respectively (p=0.006). EXIT (OR=0.083, 95% CI=0.013to 0.525, p=0.008), liver herniation (OR=16.955, 95% CI=2.342 to 122.767, p=0.005), and gestational age at diagnosis (OR=0.662, 95% CI=0.497 to 0.881, p=0.005) were independent mortality-related risk factors of all children with CDH. Ninety-nine of 116 children underwent surgery. After PSM, the postoperative survival rates of the EXIT group and non-EXIT group were 84.6% (22/26) and 76.9% (20/26), respectively (p=0.754). Liver herniation (OR=10.451, 95% CI=1.641 to 66.544, p=0.013) and gestational age at diagnosis (OR=0.736, 95% CI=0.577 to 0.938, p=0.013) were independent mortality-related risk factors of children after surgery. Conclusion: EXIT can be performed safely for selected prenatally diagnosed CDH neonates with potentially better survival and does not cause more maternal complications compared with traditional cesarean section.
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BACKGROUND: To find the predictor of optimal surgical timing for neonatal necrotizing enterocolitis (NEC) patients by analyzing the risk factors of conservative treatment and surgical therapy. METHODS: Data were collected from 184 NEC patients (Surgery, n=41; conservative treatment, n=143) between the years 2015 and 2019. Data were analyzed by univariate analysis, and multivariate binary logistic regression analysis. RESULTS: Univariate analysis showed that statistically significant differences between the surgery and conservative treatment groups. The results of multivariate Logistic regression analysis indicated intestinal wall thickening by B-ultrasound and gestational age were independent factors to predict early surgical indications of NEC (p < 0.05). The true positive rate, false positive rate, true negative rate and false negative rate in the diagnosis of necrotic bowel perforation guided by DAAS (Duke abdominal X-ray score) ≥7 and MD7 (seven clinical metrics of metabolic derangement) ≥3 were 12.8%, 0.0%, 100.0% and 87.2%, respectively. CONCLUSIONS: In summary, the ultrasound examination in NEC children showing thickening intestinal wall and poor intestinal peristalsis indicated for early operation.
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Enterocolite Necrosante , Doenças do Recém-Nascido , Perfuração Intestinal , Criança , Enterocolite Necrosante/diagnóstico por imagem , Enterocolite Necrosante/cirurgia , Idade Gestacional , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico por imagem , Doenças do Recém-Nascido/cirurgia , Perfuração Intestinal/diagnóstico por imagem , Perfuração Intestinal/cirurgia , Radiografia Abdominal , Estudos RetrospectivosRESUMO
Background: The current indications based on the clinicopathological parameters for predicting the need for surgery in neonatal necrotizing enterocolitis (NEC) are still limited. This study retrospectively analyzes the characteristics of neonatal NEC and aims to identify the risk factors for surgical intervention in NEC. Methods: Data of the NEC cases from 2015 to 2019 were collected from our institution and divided into two groups: surgical group (n = 41) and conservative treatment group (n = 143). Clinical, physical, and laboratory measures were analyzed by univariate analysis and multivariate logistic regression. The diagnostic values and receiver operative characteristic (ROC) curve were used for the assessment. Results: Univariate analysis identified significant differences between the surgical group and the conservative group in a series of clinical, physical, and laboratory measures (all p < 0.05). The results of multivariate logistic regression analysis showed that procalcitonin (adjusted OR: 167.1, 95% CI, 3.585-7,788.758, p = 0.009) and gestational age (adjusted OR: 0.85, 95% CI, 0.77-0.94, p = 0.001) were independent surgical indications for NEC. The results from ROC curve and diagnosis values demonstrated that procalcitonin [the area under the curve (AUC) = 0.864], CRP (AUC = 0.783) and fibrinogen (AUC = 0.720) had good predictive performance for surgical NEC. Conclusions: The level of procalcitonin and gestational age were found to be independent surgical indications for neonates with NEC.
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To harvest two triplet excitons of singlet fission (SF) via a two-electron transfer efficiently, the revelation of the key factors that influence the two-electron-transfer process is necessary. Here, by using steady-state and transient absorption/fluorescence spectroscopy, we investigated the two-electron-transfer process from the two triplet excitons of intramolecular SF (iSF) in a series of tetracene oligomers (dimer, trimer, and tetramer) with 7,7,8,8-tetracyanoquinodimethane (TCNQ) as an electron acceptor in solution. Quantitative two-electron transfer could be conducted for the trimer and tetramer, and the rate for the tetramer is faster than that for the trimer. However, the maximum efficiency of the two-electron transfer in the dimer is relatively low (â¼47%). The calculation result of the free energy change (ΔG) of the second-electron transfer for these three compounds (-0.024, -0.061, and -0.074 eV for the dimer, trimer, and tetramer, respectively) is consistent with the experimental observation. The much closer ΔG value to zero for the dimer should be responsible for its low efficiency of the two-electron transfer. Different ΔG values for these three oligomers are attributed to the different Coulomb repulsive energies between the two positive charges generated after the two-electron transfer that is caused by their various intertriplet distances. This result reveals for the first time the important effect of the Coulomb repulsive energy, which depends on the intertriplet distance, on the two-electron transfer process from the two triplet excitons of iSF.
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PURPOSE: To investigate the impact of COVID-19 on the treatment of children with congenital diaphragmatic hernia (CDH). METHODS: We retrospectively collected and compared the data of patients with CDH admitted between January 1, 2020 and December 31, 2021(study group) with the CDH patients admitted before the pandemic between January 1, 2018 and December 31, 2019 (control group). RESULTS: During the pandemic, 41 patients with CDH diagnosed prenatally were transferred to our hospital, and 40 underwent surgical repair. The number of patients treated in our hospital increased by 24.2% compared with the 33 patients before the pandemic. During the pandemic, the overall survival rate, postoperative survival rate and recurrence rate were 85.4%, 87.5% and 7.3%, respectively, and there were no significant differences compared with the control group (75.8%, 83.3% and 9.1%, respectively). The average length of hospital stay in patients admitted during the pandemic was longer than that in the control group (31 days vs. 16 days, P < 0.001), and the incidence of nosocomial infection was higher than that in the control group (19.5% vs. 3%, P = 0.037). CONCLUSIONS: CDH patients confirmed to be SARS-CoV-2 infection-free can receive routine treatment. Our data indicate that the implementation of protective measures during the COVID-19 pandemic, along with appropriate screening and case evaluation, do not have a negative impact on the prognosis of children.