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1.
J Am Chem Soc ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593469

RESUMO

Hydrolytically stable materials exhibiting a wide range of programmable water sorption behaviors are crucial for on-demand water sorption systems. While notable advancements in employing metal-organic frameworks (MOFs) as promising water adsorbents have been made, developing a robust yet easily tailorable MOF scaffold for specific operational conditions remains a challenge. To address this demand, we employed a topology-guided linker installation strategy using NU-600, which is a zirconium-based MOF (Zr-MOF) that contains three vacant crystallographically defined coordination sites. Through a judicious selection of three N-heterocyclic auxiliary linkers of specific lengths, we installed them into designated sites, giving rise to six new MOFs bearing different combinations of linkers in predetermined positions. The resulting MOFs, denoted as NU-606 to NU-611, demonstrate enhanced structural stability against capillary force-driven channel collapse during water desorption due to the increased connectivity of the Zr6 clusters in the resulting MOFs. Furthermore, incorporating these auxiliary linkers with various hydrophilic N sites enables the systematic modulation of the pore-filling pressure from about 55% relative humidity (RH) for the parent NU-600 down to below 40% RH. This topology-driven linker installation strategy offers precise control of water sorption properties for MOFs, highlighting a facile route to design MOF adsorbents for use in water sorption applications.

2.
J Am Chem Soc ; 146(22): 15130-15142, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38795041

RESUMO

Investigating the structure-property correlation in porous materials is a fundamental and consistent focus in various scientific domains, especially within sorption research. Metal oxide clusters with capping ligands, characterized by intrinsic cavities formed through specific solid-state packing, demonstrate significant potential as versatile platforms for sorption investigations due to their precisely tunable atomic structures and inherent long-range order. This study presents a series of Ti8Ce2-oxo clusters with subtle variations in coordinated linkers and explores their sorption behavior. Notably, Ti8Ce2-BA (BA denotes benzoic acid) manifests a distinctive two-step profile during the CO2 adsorption, accompanied by a hysteresis loop. This observation marks a new instance within the metal oxide cluster field. Of intrigue, the presence of unsaturated Ce(IV) sites was found to be correlated with the stepped sorption property. Moreover, the introduction of an electrophilic fluorine atom, positioned ortho or para to the benzoic acid, facilitated precise control over gate pressure and stepped sorption quantities. Advanced in situ techniques systematically unraveled the underlying mechanism behind this unique sorption behavior. The findings elucidate that robust Lewis base-acid interactions are established between the CO2 molecules and Ce ions, consequently altering the conformation of coordinated linkers. Conversely, the F atoms primarily contribute to gate pressure variation by influencing the Lewis acidity of the Ce sites. This research advances the understanding in fabricating metal-oxo clusters with structural flexibility and provides profound insights into their host-guest interaction motifs. These insights hold substantial promise across diverse fields and offer valuable guidance for future adsorbent designs grounded in fundamental theories of structure-property relationships.

3.
J Am Chem Soc ; 146(6): 3943-3954, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38295342

RESUMO

CALF-20, a Zn-triazolate-based metal-organic framework (MOF), is one of the most promising adsorbent materials for CO2 capture. However, competitive adsorption of water severely limits its performance when the relative humidity (RH) exceeds 40%, limiting the potential implementation of CALF-20 in practical settings where CO2 is saturated with moisture, such as postcombustion flue gas. In this work, three newly designed MOFs related to CALF-20, denoted as NU-220, CALF-20M-w, and CALF-20M-e that feature hydrophobic methyltriazolate linkers, are presented. Inclusion of methyl groups in the linker is proposed as a strategy to improve the uptake of CO2 in the presence of water. Notably, both CALF-20M-w and CALF-20M-e retain over 20% of their initial CO2 capture efficiency at 70% RH─a threshold at which CALF-20 shows negligible CO2 uptake. Grand canonical Monte Carlo simulations reveal that the methyl group hinders water network formation in the pores of CALF-20M-w and CALF-20M-e and enhances their CO2 selectivity over N2 in the presence of a high moisture content. Moreover, calculated radial distribution functions indicate that introducing the methyl group into the triazolate linker increases the distance between water molecules and Zn coordination bonds, offering insights into the origin of the enhanced moisture stability observed for CALF-20M-w and CALF-20M-e relative to CALF-20. Overall, this straightforward design strategy has afforded more robust sorbents that can potentially meet the challenge of effectively capturing CO2 in practical industrial applications.

4.
J Am Chem Soc ; 145(5): 3055-3063, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36696577

RESUMO

Reticular chemistry allows for the rational assembly of metal-organic frameworks (MOFs) with designed structures and desirable functionalities for advanced applications. However, it remains challenging to construct multi-component MOFs with unprecedented complexity and control through insertion of secondary or ternary linkers. Herein, we demonstrate that a Zr-based MOF, NU-600 with a (4,6)-connected she topology, has been judiciously selected to employ a linker installation strategy to precisely insert two linear linkers with different lengths into two crystallographically distinct pockets in a one-pot, de novo reaction. We reveal that the hydrolytic stability of these linker-inserted MOFs can be remarkably reinforced by increasing the Zr6 node connectivity, while maintaining comparable water uptake capacity and pore-filling pressure as the pristine NU-600. Furthermore, introducing hydrophilic -OH groups into the linear linker backbones to construct multivariate MOFs can effectively shift the pore-filling step to lower partial pressures. This methodology demonstrates a powerful strategy to reinforce the structural stability of other MOF frameworks by increasing the connectivity of metal nodes, capable of encouraging developments in fundamental sciences and practical applications.

5.
Inorg Chem ; 62(14): 5479-5486, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36961751

RESUMO

Acid modulator has been the most widely employed ingredient for highly crystalline metal-organic framework (MOF) synthesis. However, the mechanistic understanding of thorium (Th)-based MOF crystallization remains a great challenge due to the intrinsic properties of fast olation and oxolation reactions of Th species in solution. Here, we constructed a series of Th-based MOFs by adding different modulators (formic acid, acetic acid, trifluoroacetic acid, and benzoic acid) to a synthetic solution along with tetratopic 1,3,5,7-adamantane tetracarboxylic acid (H4ATC), a three-dimensional (3D) ligand with a rigid aliphatic backbone. This work presents an in-depth study of the structure-modulator relationship between the H4ATC ligand and coordinating modulators in the Th-based MOF crystallization process. Crystal structures of these Th-based MOFs reveal that formic acid and acetic acid modulators can compete with the H4ATC ligand to form NU-52 and NU-54; these MOFs possess Th nodes linked by the corresponding modulator. Alternatively, usage of trifluoroacetic acid and benzoic acid modulators results in NU-53 and NU-55; these MOFs possess Th nodes coordinated by only the H4ATC ligand, regardless of the modulator amount. This work highlights that both the identity and amount of modulator play a crucial role in determining the resulting Th-based MOF structures when H4ATC is selected as the coordinated ligand.

6.
Pediatr Emerg Care ; 39(7): 511-515, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37083643

RESUMO

OBJECTIVES: This study aimed to explore the clinical characteristics of septic shock in pediatric patients caused by acute appendicitis. METHODS: This case series included patients with septic shock caused by acute appendicitis in Beijing Children's Hospital between January 2015 and December 2020. RESULTS: Six patients with septic shock caused by acute appendicitis were enrolled. One patient was an infant with extremely low weight; 2 patients were obese. The diagnosis was delayed in 4 patients (the time from onset to diagnosis was 5 days in 3 children and 4 days in 1 child). All patients had abnormally raised inflammatory markers (C-reactive protein 119.17 ± 48.36 mg/L, procalcitonin 129.95 ± 86.09 ng/mL). Severe abdominal infection was found in all patients. There was appendix perforation in 4 patients and diffused peritonitis in 3 patients. Two patients had metabolic diseases (Wilson disease and decreased biotinase activity, respectively). Five patients had an appendectomy and 1 patient received conservative treatment. Five patients were discharged in stable condition, while 1 patient died. CONCLUSIONS: Children with delayed diagnosis, abnormal body weight, significant elevation in inflammatory markers, and underlying metabolic disease may be at greater risk of complicated appendicitis and septic shock. EVIDENCEBASED MEDICINE: Level of Evidence: IV.


Assuntos
Apendicite , Apêndice , Choque Séptico , Lactente , Criança , Humanos , Apendicite/complicações , Apendicite/diagnóstico , Apendicite/cirurgia , Choque Séptico/etiologia , Choque Séptico/complicações , Apendicectomia , Abdome , Doença Aguda , Estudos Retrospectivos
7.
J Am Chem Soc ; 144(8): 3554-3563, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35179900

RESUMO

Solid supports are crucial in heterogeneous catalysis due to their profound effects on catalytic activity and selectivity. However, elucidating the specific effects arising from such supports remains challenging. We selected a series of metal-organic frameworks (MOFs) with 8-connected Zr6 nodes as supports to deposit molybdenum(VI) onto to study the effects of pore environment and topology on the resulting Mo-supported catalysts. As characterized by X-ray absorption spectroscopy (XAS) and single-crystal X-ray diffraction (SCXRD), we modulated the chemical environments of the deposited Mo species. For Mo-NU-1000, the Mo species monodentately bound to the Zr6 nodes were anchored in the microporous c-pore, but for Mo-NU-1008 they were bound in the mesopore of Mo-NU-1008. Both monodentate and bidentate modes were found in the mesopore of Mo-NU-1200. Cyclohexene epoxidation with H2O2 was probed to evaluate the support effect on catalytic activity and to unveil the resulting structure-activity relationships. SCXRD and XAS studies demonstrated the atomically precise structural differences of the Mo binding motifs over the course of cyclohexene epoxidation. No apparent structural change was observed for Mo-NU-1000, whereas the monodentate mode of Mo species in Mo-NU-1008 and the monodentate and bidentate Mo species in Mo-NU-1200 evolved to a new bidentate mode bound between two adjacent oxygen atoms from the Zr6 node. This work demonstrates the great advantage of using MOF supports for constructing heterogeneous catalysts with modulated chemical environments of an active species and elucidating structure-activity relationships in the resulting reactions.


Assuntos
Estruturas Metalorgânicas , Molibdênio , Catálise , Cicloexenos , Peróxido de Hidrogênio , Estruturas Metalorgânicas/química , Molibdênio/química , Relação Estrutura-Atividade
8.
Int J Colorectal Dis ; 37(5): 1127-1132, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35449241

RESUMO

PURPOSE: This study was aiming to explore the risk factors contributing to enterostomy in neonates with Hirschsprung disease (HD) to provide a reference for clinicians to make treatment decisions. METHODS: Medical records of 284 patients diagnosed with HD during the neonatal period were retrospectively analyzed. The patients were divided into 2 groups based on operative intervention (one stage transanal pull-through, versus enterotomy and staged transanal pull-through). Univariate and multivariable logistic regression analysis was performed to identify risk factors contributing to enterostomy. RESULTS: The incidence of enterostomy was 12.0% (34/284) in neonates with HD. Univariate and multivariate logistic regression analysis showed that serum albumin < 25.4 g/L, radiographic results as subphrenic free air, and level of aganglionosis with long-segment or total colonic aganglionosis (TCA) were independent risk factors of enterostomy in neonates, with OR of 42.045 (6.131, 288.319), 285.558 (26.651, 3059.694) and 15.573 (4.319, 56.157), respectively. CONCLUSIONS: The low serum albumin level, bowel perforation, and level of aganglionosis with long-segment or TCA could influence the occurrence of enterostomy in neonates with HD.


Assuntos
Enterostomia , Doença de Hirschsprung , Enterostomia/efeitos adversos , Doença de Hirschsprung/cirurgia , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica
9.
Artigo em Inglês | MEDLINE | ID: mdl-36443144

RESUMO

BACKGROUND: The high incidence of gallstone recurrence was a major concern for laparoscopic gallbladder-preserving surgery. This study aimed to investigate the risk factors for gallstone recurrence after gallbladder-preserving surgery and to establish an individualized nomogram model to predict the risk of gallstone recurrence. METHODS: The clinicopathological and follow-up data of 183 patients who were initially diagnosed with gallstones and treated with gallbladder-preserving surgery at our hospital from January 2012 to January 2019 were retrospectively collected. The independent predictive factors for gallstone recurrence following gallbladder-preserving surgery were identified by multivariate logistic regression analysis. A nomogram model for the prediction of gallstone recurrence was constructed based on the selected variables. The C-index, receiver operating characteristic (ROC) curve and calibration curve were used to evaluate the predictive power of the nomogram model for gallstone recurrence. RESULTS: During the follow-up period, a total of 65 patients experienced gallstone recurrence, and the recurrence rate was 35.5%. Multivariate logistic regression analysis revealed that the course of gallstones > 2 years [odds ratio (OR) = 2.567, 95% confidence interval (CI): 1.270-5.187, P = 0.009], symptomatic gallstones (OR = 2.589, 95% CI: 1.059-6.329, P = 0.037), multiple gallstones (OR = 2.436, 95% CI: 1.133-5.237, P = 0.023), history of acute cholecystitis (OR = 2.778, 95% CI: 1.178-6.549, P = 0.020) and a greasy diet (OR = 2.319, 95% CI: 1.186-4.535, P = 0.014) were independent risk factors for gallstone recurrence after gallbladder-preserving surgery. A nomogram model for predicting the recurrence of gallstones was established based on the above five variables. The results showed that the C-index of the nomogram model was 0.692, suggesting it was valuable to predict gallstone recurrence. Moreover, the calibration curve showed good consistency between the predicted probability and actual probability. CONCLUSIONS: The nomogram model for the prediction of gallstone recurrence might help clinicians develop a proper treatment strategy for patients with gallstones. Gallbladder-preserving surgery should be cautiously considered for patients with high recurrence risks.

10.
Pediatr Surg Int ; 39(1): 31, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459267

RESUMO

PURPOSE: Alimentary tract duplication involving the rectum (ATD-R) is rare. The purpose of the study was to describe the features of pediatric ATD-R patients and propose a surgical management strategy. METHODS: Nine consecutive children operated on for ATD-R at a tertiary center for pediatrics from January 2010 to June 2021 were retrospectively reviewed and followed up. Eighty-six children with the same diagnosis from the literature were reviewed to assist the investigation. Classifications of ATD-R consisted of cystic, tubular, and diverticular. RESULTS: Surgical treatment and histopathological examination identified six females and three males with ATD-R. Initial clinical symptoms included perianal lesions, abnormal discharge, and anorectal malformation (ARM). Apart from one tubular ATD-R patient with cloaca malformation, the other eight patients had normal-developed anorectum. Complete or partial lesion resection maintaining the integrity of the proper colorectum was a principle of surgery. Six patients were followed up for a median time of 71 (range 12-121) months with good prognoses. A surgical management strategy of ATD-R in children was proposed. CONCLUSIONS: ATD-R commonly occurred concurrently with normal-developed anorectum, seldom combined with ARM. ATD-R should be considered as a differential diagnosis in anorectal symptoms. The timely and appropriate operation was curative.


Assuntos
Malformações Anorretais , Reto , Feminino , Masculino , Humanos , Criança , Reto/cirurgia , Estudos Retrospectivos , Pelve , Trato Gastrointestinal , Malformações Anorretais/diagnóstico , Malformações Anorretais/cirurgia
11.
Pediatr Surg Int ; 38(11): 1533-1540, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36030350

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of transanal endorectal pull-through (TEPT) and the long-term outcomes in newborns with Hirschsprung disease (HD). METHODS: A total of 229 newborns with HD underwent one-stage TEPT between 2007 and 2020, and the diagnoses were confirmed by rectal biopsy. The perioperative clinical course for all patients was reviewed, and the postoperative short- and long-term outcomes were assessed. RESULTS: A total of 229 neonates (187 male and 42 female) had a median age at TEPT of 17 days (range 6-28 days). Sixty-eight patients (29.7%) underwent TEPT combined with an abdominal approach or laparoscopy. Early postoperative complications (using the Clavien-Dindo grading system) were documented in 36 patients (15.7%), and late postoperative complications were noted in 9 patients (3.9%). The follow-up period in the remaining 165 children ranged from 1.2 to 14.0 years (median 5.0 years). A total of 106 of the patients older than four years old took part in an interview about bowel function, and 85 patients (80.2%) had bowel function scores (BFS) ≥ 18. CONCLUSION: TEPT is effective and safe for HD in the neonatal period and presents with a low rate of complications and an acceptable outcome.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Doença de Hirschsprung , Laparoscopia , Canal Anal/cirurgia , Criança , Pré-Escolar , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Feminino , Doença de Hirschsprung/complicações , Humanos , Lactente , Recém-Nascido , Laparoscopia/efeitos adversos , Masculino , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
12.
J Am Chem Soc ; 143(11): 4302-4310, 2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33706512

RESUMO

The understanding of structure-activity relationships at the atomic level has played a profound role in heterogeneous catalysis, providing valuable insights into designing suitable heterogeneous catalysts. However, uncovering the detailed roles of how such active species' structures affect their catalytic performance remains a challenge owing to the lack of direct structural information on a specific active species. Herein, we deposited molybdenum(VI), an active species in oxidation reactions, on the Zr6 node of a mesoporous zirconium-based metal-organic framework (MOF) NU-1200, using solvothermal deposition in MOFs (SIM). Due to the high crystallinity of the NU-1200 support, the precise structure of the resulting molybdenum catalyst, Mo-NU-1200, was characterized through single-crystal X-ray diffraction (SCXRD). Two distinct anchoring modes of the molybdenum species were observed: one mode (Mo1), displaying an octahedral geometry, coordinated to the node through one terminal oxygen atom and the other mode (Mo2) coordinated to two adjacent Zr6 node oxygen atoms in a tetrahedral geometry. To investigate the role of base in the catalytic activity of these Mo centers, we assessed the activity of Mo-NU-1200 for the aerobic oxidation of 4-methoxybenzyl alcohol as a model reaction. The results revealed that Mo-NU-1200 exhibited remarkably higher catalytic reactivity under base-free conditions, while the presence of base inhibited the catalytic reactivity of this species. SCXRD studies revealed that the molybdenum binding motifs (structures of the supported metal on the Zr6 node in the MOF) changed over the course of the reactions. Following the oxidation without base, both pristine coordination modes (Mo1 and Mo2) evolved into a new coordination mode (Mo3), in which the molybdenum atom coordinated to two adjacent oxygen atoms from the Zr6 node in an octahedral geometry, while in the presence of base, the pristine Mo1 coordination mode evolved entirely into the pristine Mo2. This study demonstrates the direct observation of an active species' structural evolution from metal installation to subsequent catalytic reaction. As a result, these subtle structural changes in catalyst binding motifs led to distinct differences in catalytic activities, providing a compelling strategy for elucidating structure-activity relationships.

13.
BMC Pediatr ; 21(1): 543, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34861834

RESUMO

BACKGROUND: To analyze the possible causes, treatment and outcomes of postoperative pneumothorax in patients with Gross type C esophageal atresia/tracheoesophageal fistula (EA/TEF). METHODS: Medical records of patients with Gross type C EA/TEF who were diagnosed and treated in Beijing Children's Hospital from January 2007 to January 2020 were retrospectively collected. They were divided into 2 groups according to whether postoperative pneumothorax occurred. Univariate and multivariate logistic regression analysis were performed to identify risk factors for pneumothorax. RESULTS: A total of 188 patients were included, including 85 (45 %) in the pneumothorax group and 103 (55 %) in the non-pneumothorax group. Multivariate logistic regression analysis showed that postoperative anastomotic leakage [P < 0.001, OR 3.516 (1.859, 6.648)] and mechanical ventilation [P = 0.012, OR 2.399 (1.210, 4.758)] were independent risk factors for pneumothorax after EA/TEF repair. Further analysis of main parameters of mechanical ventilation after surgery showed that none of them were clearly related to the occurrence of pneumothorax. Among the 85 patients with pneumothorax, 33 gave up after surgery and 52 received further treatment [conservative observation (n = 20), pleural puncture (n = 11), pleural closed drainage (n = 9), both pleural puncture and closed drainage (n = 12)]. All of the 52 patients were cured of pneumothorax at discharge. CONCLUSIONS: Anastomotic leakage and postoperative mechanical ventilation were risk factors for pneumothorax after repair of Gross type C EA/TEF, but the main parameters of mechanical ventilation had no clear correlation with pneumothorax. After symptomatic treatment, the prognosis of pneumothorax was good.


Assuntos
Atresia Esofágica , Pneumotórax , Fístula Traqueoesofágica , Criança , Atresia Esofágica/complicações , Atresia Esofágica/cirurgia , Humanos , Pneumotórax/epidemiologia , Pneumotórax/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fístula Traqueoesofágica/etiologia , Fístula Traqueoesofágica/cirurgia , Resultado do Tratamento
14.
BMC Surg ; 21(1): 403, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809633

RESUMO

BACKGROUND: To compare the clinical outcomes between thoracoscopic approach and thoracotomy surgery in patients with Gross type C Esophageal atresia (EA) and tracheoesophageal fistula (TEF). METHODS: Patients with Gross type C EA/TEF who underwent surgery from January 2007 to January 2020 at Beijing Children's Hospital were retrospectively analyzed. The patients were divided into two groups according to surgical approaches. The perioperative factors and postoperative complications were compared among the two groups. RESULTS: One hundred and ninety patients (132 boys and 58 girls) with a median birth weight of 2975 (2600, 3200) g were included. The primary operations were performed via thoracoscopic (n = 62) and thoracotomy (n = 128) approach. After comparison of clinical characteristics between the two groups, we found that there were statistically significant differences in associated anomalies, method of fistula closure, duration of mechanical ventilation after surgery, feeding option before discharge, management of pneumothorax, and prognosis (all P < 0.05). To a certain extent, thoracoscopic surgery reduced the incidence of anastomotic leakage and increased the incidence of anastomotic stricture in this study. However, there were no statistically significant differences between the two groups in terms of operative time, postoperative pneumothorax, anastomotic leakage, anastomotic stricture, and recurrent tracheoesophageal fistula (all P > 0.05). CONCLUSIONS: Thoracoscopy surgery for Gross type C EA/TEF is a safe and effective, minimally invasive technique with comparable operative time and incidence of postoperative complications.


Assuntos
Atresia Esofágica , Fístula Traqueoesofágica , Criança , Atresia Esofágica/cirurgia , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Toracoscopia , Toracotomia , Fístula Traqueoesofágica/epidemiologia , Fístula Traqueoesofágica/cirurgia , Resultado do Tratamento
15.
Clin Otolaryngol ; 46(5): 1028-1036, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33787003

RESUMO

OBJECTIVE: Hyaluronic acid (HA) can be degraded over time. However, persistence of the effects after injection laryngoplasty (IL) for unilateral vocal fold paralysis (UVFP), longer than expected from HA longevity, has been observed. The purpose of the study was to develop a methodology with clinical utility for objective evaluation of the temporal change in HA volume after IL using artificial intelligence (AI)-based ultrasonic assessment. DESIGN, SETTING AND PARTICIPANTS: Imaging phantoms simulating injected HA were built in different volumes for designing the algorithm for machine learning. Subsequently, five adult patients who had undergone IL with HA for UVFP were recruited for clinical evaluation. MAIN OUTCOME MEASURES: Estimated volumes were evaluated for injected HA by the automatic algorithm as well as voice outcomes at 2 weeks, and 2 and 6 months after IL. RESULTS: On imaging phantoms, contours on each frame were described well by the algorithm and the volume could be estimated accordingly. The error rates were 0%-9.2%. Moreover, the resultant contours of the HA area were captured in detail for all participants. The estimated volume decreased to an average of 65.76% remaining at 2 months and to a minimal amount at 6 months while glottal closure remained improved. CONCLUSION: The volume change of the injected HA over time for an individual was estimated non-invasively by AI-based ultrasonic image analysis. The prolonged effect after treatment, longer than HA longevity, was demonstrated objectively for the first time. The information is beneficial to achieve optimal cost-effectiveness of IL and improve the life quality of the patients.


Assuntos
Inteligência Artificial , Ácido Hialurônico/uso terapêutico , Laringoplastia/métodos , Ultrassonografia de Intervenção/métodos , Paralisia das Pregas Vocais/diagnóstico por imagem , Paralisia das Pregas Vocais/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Ácido Hialurônico/administração & dosagem , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Fatores de Tempo
16.
J Am Chem Soc ; 142(51): 21428-21438, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33290083

RESUMO

While linkers with various conformations pose challenges in the design and prediction of metal-organic framework (MOF) structures, they ultimately provide great opportunities for the discovery of novel structures thereby enriching structural diversity. Tetratopic carboxylate linkers, for example, have been widely used in the formation of Zr-based MOFs due to the ability to target diverse topologies, providing a promising platform to explore their mechanisms of formation. However, it remains a challenge to control the resulting structures when considering the complex assembly of linkers with unpredicted conformations and diverse Zr6 node connectivities. Herein, we systematically explore how solvents and modulators employed during synthesis influence the resulting topologies of Zr-MOFs, choosing H4TCPB-Br2 (1,4-dibromo-2,3,5,6-tetrakis(4-carboxyphenyl)benzene) as a representative tetratopic carboxylate linker. By modulating the reaction conditions, the conformations of the linker and the connectivities of the Zr6 node can be simultaneously tuned, resulting in four types of structures: a new topology (NU-500), she (NU-600), scu (NU-906), and csq (NU-1008). Importantly, we have synthesized the first 5-connected Zr6 node to date with the (4,4,4,5)-connected framework, NU-500. We subsequently performed detailed structural analyses to uncover the relationship between the structures and topologies of these MOFs and demonstrated the crucial role that the flexible linker played to access varied structures by different degrees of linker deformation. Due to a variety of pore structures ranging from micropores to hierarchical micropores and mesopores, the resulting MOFs show drastically different behaviors for the adsorption of n-hexane and dynamic adsorption of 2-chloroethyl ethyl sulfide (CEES) under dry and humid conditions.


Assuntos
Poluentes Ambientais/química , Poluentes Ambientais/isolamento & purificação , Estruturas Metalorgânicas/química , Zircônio/química , Adsorção , Benzeno/química , Cinética , Gás de Mostarda/análogos & derivados , Gás de Mostarda/química , Gás de Mostarda/isolamento & purificação , Porosidade
17.
BMC Pediatr ; 20(1): 499, 2020 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-33126876

RESUMO

BACKGROUND: Preoperative diagnosis of total colonic aganglionosis is important for the rational choice of treatment. The present study aimed to evaluate the diagnostic performance of radiographic signs on preoperative barium enema in patients with total colonic aganglionosis. METHODS: Forty-four patients [41 (3-659) days] with total colonic aganglionosis, including 17 neonatal patients, who received preoperative barium enema at Beijing Children's Hospital, from January 2007 to December 2019 were included. All radiographs were retrospectively restudied by 2 pediatric radiologists to ascertain radiographic signs including rectosigmoid index, transition zone, irregular contraction, gas-filled small bowel, microcolon, question-mark-shaped colon and ileocecal valve reflux. Kappa test was performed to assess the accuracy and consistency of the radiographic signs. RESULTS: The 2 radiologists showed slight agreement for gas-filled small bowel, microcolon and rectosigmoid index, fair agreement for transition zone and irregular contraction, and moderate agreement for question-mark-shaped colon and ileocecal valve reflux (Kappa values, 0.043, 0.075, 0.103, 0.244, 0.397, 0.458 and 0.545, respectively). In neonatal patients, the 2 radiologists showed moderate agreement for ileocecal valve reflux and substantial agreement for question-mark-shaped colon (Kappa values, 0.469 and 0.667, respectively). In non-neonatal patients, the 2 radiologists showed substantial agreement for ileocecal valve reflux (Kappa value, 0.628). In 36 patients with total colonic aganglionosis extending to the ileum, the accuracies of question-mark-shaped colon, ileocecal valve reflux and the combination of both were 47%, 53%, and 75%, respectively, in one radiologist and 53%, 50% and 72%, respectively, in the other radiologist. CONCLUSIONS: Ileocecal valve reflux is a relatively reliable radiographic sign for diagnosing total colonic aganglionosis and could improve the diagnostic accuracy upon combination with question-mark-shaped colon.


Assuntos
Doença de Hirschsprung , Enema Opaco , Criança , Enema , Doença de Hirschsprung/diagnóstico por imagem , Humanos , Recém-Nascido , Estudos Retrospectivos
18.
J Am Chem Soc ; 141(51): 20016-20021, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31833359

RESUMO

Metal-organic frameworks (MOFs) are promising candidates for the catalytic hydrolysis of nerve agents and their simulants. Though highly efficient, bulk water and volatile bases are often required for hydrolysis with these MOF catalysts, preventing real-world implementation. Herein we report a generalizable and scalable approach for integrating MOFs and non-volatile polymeric bases onto textile fibers for nerve agent hydrolysis. Notably, the composite material showed similar reactivity under ambient conditions compared to the powder material in aqueous alkaline solution. This represents a critical step toward a unified strategy for nerve agent hydrolysis in practical settings, which can significantly reduce the dimensions of filters and increase the efficiency of protective suits.

19.
J Am Chem Soc ; 141(39): 15626-15633, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31532665

RESUMO

Organophosphonate-based nerve agents, such as VX, Sarin (GB), and Soman (GD), are among the most toxic chemicals to humankind. Recently, we have shown that Zr-based metal-organic frameworks (Zr-MOFs) can effectively catalyze the hydrolysis of these toxic chemicals for diminishing their toxicity. On the other hand, utilizing these materials in powder form is not practical, and developing scalable and economical processes for integrating these materials onto fibers is crucial for protective gear. Herein, we report a scalable, template-free, and aqueous solution-based synthesis strategy for the production of Zr-MOF-coated textiles. Among all MOF/fiber composites reported to date, the MOF-808/polyester fibers exhibit the highest rates of nerve agent hydrolysis. Moreover, such highly porous fiber composites display significantly higher protection time compared to that of its parent fabric for a mustard gas simulant, 2-chloroethyl ethyl sulfide (CEES). A decreased diffusion rate of toxic chemicals through the MOF layer can provide time needed for the destruction of the harmful species.

20.
Indian J Med Res ; 148(6): 728-733, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30778007

RESUMO

BACKGROUND & OBJECTIVES: Hepatic venous malformation gradually develops over time and exhibits the malignant biological behaviours of being locally invasive, causing morphological and functional damage to local tissue, and may even cause systemic coagulopathy. Studies show that galectin-3(Gal-3) expression is closely associated with local invasion of malignant tumours. In this study an attempt was made to assess the clinical significance of Gal-3 in local invasion during hepatic venous malformation in patients. METHODS: Gal-3 protein and its mRNA expression were examined using immunohistochemistry and in situ hybridization in a total of 126 patients with hepatic venous malformation. For control tissue, 20 cases of normal tissue distal to surgical margins were also examined. In addition, the association between Gal-3 expression and pathological parameters was analyzed in hepatic venous malformation patients. RESULTS: Gal-3 mRNA positivity was observed in 65.08 per cent (82/126) of hepatic venous malformation tissue samples, which was higher than the rate of 20 per cent (4/20) (P <0.05) seen in control tissues. Gal-3 protein positivity was observed in 58.73 per cent (74/126) of hepatic venous malformation tissue samples, which was higher than the rate of 15 per cent (3/20) (P <0.05) seen in the normal tissue. Gal-3 expression was not significantly associated with age or gender. However, there was a significant association between Gal-3 positivity and lesion size, local invasion depth, and involvement with the hepatic vein and the portal system. INTERPRETATION & CONCLUSIONS: Local tissue invasion and destruction by hepatic venous malformation may be related to the upregulation of Gal-3. Gal-3 expression and the development of venous malformation may be related and needs to be studied further.


Assuntos
Malformações Arteriovenosas/genética , Malformações Arteriovenosas/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Adulto , Malformações Arteriovenosas/patologia , Proteínas Sanguíneas , Estudos de Casos e Controles , Feminino , Galectinas , Expressão Gênica , Veias Hepáticas/patologia , Humanos , Fígado/irrigação sanguínea , Masculino , Veia Porta/patologia , RNA Mensageiro/metabolismo
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