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1.
Article in English | MEDLINE | ID: mdl-39420457

ABSTRACT

Photochromic hydrogen-bonded organic frameworks (HOFs) can introduce different luminescent functional groups to achieve synergistic controlled multiple color change properties, which are in great demand for diverse information encryption applications. We report in this paper switchable photochromic and photoluminescent dual luminescent functional group HOFs constructed with synergistic effects by N,N'-bis(2-phenylalanine)-1,4,5,8-naphthalenediimine (H2PheNDI) and benzenecarboximidamide 4,4'-azobis(hydrochloride) (AZBH). The crystal powder of iHOF-41 is orange-red in color, which can be changed to black under the irradiation of a 365 nm ultraviolet (UV) light source for 15 min. The photoisomerization rate of the crystal solution under continuous UV irradiation for 5 h was close to 99%. The composite membranes can achieve the properties of photochromism and photoluminescence when they are discolored under 365 nm UV irradiation and, at the same time, excite red bright fluorescence. This work achieves the construction of HOFs based on switching biluminescent functional groups and explores the synergistic mechanism of the photoisomerization process and photochromism as well as its practical application in information encryption.

2.
Chem Commun (Camb) ; 60(81): 11576-11579, 2024 Oct 08.
Article in English | MEDLINE | ID: mdl-39314186

ABSTRACT

Herein, a novel ionic hydrogen-bonded organic framework (iHOF-12) was synthesized. The 5-fold interpenetrating network structure and charge-assisted synergistic effects enable iHOF-12 to maintain robustness under demanding conditions and attain excellent proton conductivity of 1.23 × 10-2 S cm-1, which contributes to the enhancement of the DMFC performance.

3.
Chem Asian J ; : e202400870, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39316040

ABSTRACT

Hydrogen-bonded organic frameworks (HOFs) are crystalline materials assembled by intermolecular hydrogen-bonding interactions, and their hydrogen-bonding structures are effective pathways for proton transport. Herein, we synthesize iHOF-45 using 4,4'-diaminodiphenylmethane and 1,3,6,8-pyrenetetrasulfonicacid sodium salt with 2D hydrogen-bonding networks. The introduction of ionic bond based on the weak hydrogen-bonding force was employed to enhance the stability of ionic HOFs (iHOFs). Thermal analyses demonstrated that iHOF-45 exhibited excellent thermal stability up to 332 °C. The proton conductivity of iHOF-45 was evaluated, demonstrating a notable increase with rising temperature and RH. At 100 °C and 98% RH, the conductivity reached 5.25 × 10-3 S cm-1. The activation energy (Ea) of iHOF-45 was calculated to be 0.281 eV for 98% RH, and the proton conduction was attributed to the Grotthuss mechanism, whereby the protons were transported in 2D hydrogen-bonding networks. Moreover, iHOF-45 was doped into SPEEK to prepare composite membranes, the proton conductivity of the 15%-iHOF-45/SPEEK membrane reached 9.52 × 10-2 S cm-1 at 80 °C and 98% RH, representing a 45.1% increase over that of the SPEEK. This suggests that doping enhances the proton conductivity of SPEEK and providing a reference for the development of high proton conductivity materials.

4.
World J Gastroenterol ; 30(25): 3132-3139, 2024 Jul 07.
Article in English | MEDLINE | ID: mdl-39006380

ABSTRACT

In this editorial, we comment on the article by Chen et al. Metabolic dysfunction-associated fatty liver disease (MAFLD) is a global public health burden whose incidence has risen concurrently with overweight and obesity. Given its detrimental health impact, early identification of at-risk individuals is crucial. MAFLD diagnosis is based on evidence of hepatic steatosis indicated by liver biopsy, imaging, or blood biomarkers, and one of the following conditions: Overweight/ obesity, type 2 diabetes mellitus, or metabolic dysregulation. However, in large-scale epidemiological studies, liver biopsies are not feasible. The application of techniques such as ultrasonography, computed tomography, magnetic resonance imaging, and magnetic resonance spectroscopy is restricted by their limited sensitivity, low effectiveness, high costs, and need for specialized software. Blood biomarkers offer several advantages, particularly in large-scale epidemiological studies or clinical scenarios where traditional imaging techniques are impractical. Analysis of cumulative effects of excess high-normal blood alanine aminotransferase (ALT) levels of blood ALT levels could facilitate identification of at-risk patients who might not be detected through conventional imaging methods. Accordingly, investigating the utility of blood biomarkers in MAFLD should enhance early detection and monitoring, enabling timely intervention and management and improving patient outcomes.


Subject(s)
Alanine Transaminase , Biomarkers , Humans , Biomarkers/blood , Alanine Transaminase/blood , Liver/diagnostic imaging , Liver/pathology , Non-alcoholic Fatty Liver Disease/diagnosis , Non-alcoholic Fatty Liver Disease/blood , Non-alcoholic Fatty Liver Disease/epidemiology , Risk Factors , Obesity/complications , Obesity/diagnosis , Obesity/blood , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Early Diagnosis
5.
Chemistry ; 30(17): e202303580, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38179818

ABSTRACT

Hydrogen-bonded organic frameworks (HOFs) are a class of crystalline framework materials assembled by hydrogen bonds. HOFs have the advantages of high crystallinity, mild reaction conditions, good solution processability, and reproducibility. Coupled with the reversibility and flexibility of hydrogen bonds, HOFs can be assembled into a wide diversity of crystalline structures. Since the bonding energy of hydrogen bonds is lower than that of ligand and covalent bonds, the framework of HOFs is prone to collapse after desolventisation and the stability is not high, which limits the development and application of HOFs. In recent years, numerous stable and functional HOFs have been developed by π-π stacking, highly interpenetrated networks, charge-assisted, ligand-bond-assisted, molecular weaving, and covalent cross-linking. Charge-assisted ionic HOFs introduce electrostatic attraction into HOFs to improve stability while enriching structural diversity and functionality. In this paper, we review the development, the principles of rational design and assembly of charge-assisted ionic HOFs, and introduces the different building block construction modes of charge-assisted ionic HOFs. Highlight the applications of charge-assisted ionic HOFs in gas adsorption and separation, proton conduction, biological applications, etc., and prospects for the diverse design of charge-assisted ionic HOFs structures and multifunctional applications.

6.
Chemistry ; 29(26): e202300028, 2023 May 08.
Article in English | MEDLINE | ID: mdl-36807423

ABSTRACT

Two ionic hydrogen-bonded organic frameworks (iHOF-10, iHOF-11) were prepared using 1,1'-diamino-4,4'-bipyridine diiodide (Dbpy ⋅ 2I) and tetrakis(4-sulfophenyl)ethylene (H4 TPE). With increasing RH and temperature, water molecules induce single crystal to single crystal (SCSC) transformation of iHOF-10, resulting in the formation of iHOF-11. At 90 °C, 98 % RH, the proton conductivity of iHOF-11 (7.03×10-3  S cm-1 ) is 2.09 times higher than iHOF-10 (3.37×10-3  S cm-1 ). At 50 °C, 98 % RH, iHOF-11 (9.49×10-4  S cm-1 ) is 19.06 times higher than iHOF-10 (4.98×10-5  S cm-1 ). The proton conductivity shows water molecules enter the crystal and induce crystal transformation and reorganization of the hydrogen bonding structure, thus increasing the proton conductivity and stability.

7.
World J Pediatr ; 14(4): 399-403, 2018 08.
Article in English | MEDLINE | ID: mdl-29508360

ABSTRACT

BACKGROUND: To determine whether ex utero intrapartum treatment (EXIT) is an appropriate approach for managing fetuses antenatally diagnosed with giant congenital omphaloceles. METHODS: We retrospectively reviewed patients with omphaloceles who underwent either an EXIT procedure or a traditional repair surgery. Basic and clinical parameters including gender, gestational age, birth weight, maternal blood loss, operative times and operative complications were analyzed. During the 6-12-month follow-ups, postoperative complications including bowel obstruction, abdominal infections, postoperative abdominal distension were monitored, and survival rate was analyzed. RESULTS: A total of seven patients underwent the EXIT procedure and 11 patients underwent the traditional postnatal surgery. We found no differences in maternal age, gestational age at diagnosis, gestational age at delivery and birth weight between the two groups. In the EXIT group, the average operation time for mother was 68.3 ± 17.5 minutes and the average maternal blood loss was 233.0 ± 57.7 mL. The operation time in the EXIT group (22.0 ± 4.5 minutes) was shorter than that in the traditional group (35 ± 8.7 minutes), but the length of hospital stay in the EXIT group (20.5 ± 3.1 days) was longer than that in the traditional group (15.7 ± 2.5 days, P < 0.05). During the follow-up, one patient in the EXIT group had an intestinal obstruction, one developed abdominal compartment syndrome and one died in the traditional group. CONCLUSIONS: In our experience, EXIT is a safe and effective procedure for the treatment of giant congenital omphaloceles. However, more experience is needed before this procedure can be widely recommended.


Subject(s)
Fetal Diseases/surgery , Hernia, Umbilical/surgery , Herniorrhaphy/methods , Patient Safety , Pregnancy Outcome , Ultrasonography, Prenatal/methods , Cohort Studies , Female , Fetal Diseases/diagnostic imaging , Follow-Up Studies , Hernia, Umbilical/diagnostic imaging , Humans , Infant, Newborn , Male , Pregnancy , Prenatal Care/methods , Retrospective Studies , Risk Assessment , Treatment Outcome
8.
Chin Med J (Engl) ; 129(12): 1491-7, 2016 Jun 20.
Article in English | MEDLINE | ID: mdl-27270548

ABSTRACT

OBJECTIVE: To systematically summary the updated results about the pathogenesis of Hirschsprung's-associated enterocolitis (HAEC). Besides, we discussed the research key and direction based on these results. DATA SOURCES: Our data cited in this review were obtained mainly from PubMed from 1975 to 2015, with keywords "Hirschsprung enterocolitis", "Hirschsprung's enterocolitis", "Hirschsprung's-associated enterocolitis", "Hirschsprung-associated enterocolitis", "HAEC", and "EC". STUDY SELECTION: Articles regarding the pathogenesis of HAEC were selected, and the articles mainly regarding the diagnosis, surgical approach, treatment, and follow-up were excluded. RESULTS: Several factors, mainly including mucus barrier, intestinal microbiota, and immune function, as well as some other factors such as genetic variations and surgical reasons, have been found to be related to the pathogenesis of HAEC. Changed quantity and barrier property of mucus, different composition of microbiota, and an abnormal immune state work together or separately trigger HAEC. CONCLUSIONS: The maintenance of intestinal homeostasis is due to a well cooperation of microbiota, mucus barrier, and immune system. If any part presents abnormal, intestinal homeostasis will be broken. Meanwhile, for patients with Hirschsprung's disease or HAEC, dysfunction of these parts has been found. Thus, the happening of HAEC may be mainly attributed to the disorders of intestinal microbiota, mucus barrier, and immune system.


Subject(s)
Enterocolitis/pathology , Hirschsprung Disease/pathology , Animals , Enterocolitis/etiology , Hirschsprung Disease/complications , Humans , Intestines/microbiology , Intestines/pathology
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