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1.
J Biomech ; 167: 112086, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38615481

RESUMO

Accurate assessment of portacaval pressure gradient (PCG) in patients with portal hypertension (PH) is of great significance both for diagnosis and treatment. This study aims to develop a noninvasive method for assessing PCG in PH patients and evaluate its accuracy and effectiveness. This study recruited 37 PH patients treated with transjugular intrahepatic portosystemic shunt (TIPS). computed tomography angiography was used to create three dimension (3D) models of each patient before and after TIPS. Doppler ultrasound examinations were conducted to obtain the patient's portal vein flow (or splenic vein and superior mesenteric vein). Using computational fluid dynamics (CFD) simulation, the patient's pre-TIPS and post-TIPS PCG was determined by the 3D models and ultrasound measurements. The accuracy of these noninvasive results was then compared to clinical invasive measurements. The results showed a strong linear correlation between the PCG simulated by CFD and the clinical invasive measurements both before and after TIPS (R2 = 0.998, P < 0.001 and R2 = 0.959, P < 0.001). The evaluation accuracy of this noninvasive method reached 94 %, and the influence of ultrasound result errors on the numerical accuracy was found to be marginal if the error was less than 20 %. Furthermore, the information about the hemodynamic environment in the portal system was obtained by this numerical method. Spiral flow patterns were observed in the portal vein of some patients. In a conclusion, this study proposes a noninvasive numerical method for assessing PCG in PH patients before and after TIPS. This method can assist doctors in accurately diagnosing patients and selecting appropriate treatment plans. Additionally, it can be used to further investigate potential biomechanical causes of complications related to TIPS in the future.


Assuntos
Hipertensão Portal , Derivação Portossistêmica Transjugular Intra-Hepática , Humanos , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Hidrodinâmica , Veia Porta/diagnóstico por imagem , Hipertensão Portal/diagnóstico por imagem , Hemodinâmica
2.
Dalton Trans ; 53(11): 4968-4975, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38390698

RESUMO

Developing luminescent materials with suitable correlated color temperature (CCT) and sufficient color-rendering index (CRI) is a challenging problem in the field of commercialized warm white LED lighting. Herein, a novel metal-organic gel (MOG) material named YTU-G-1(SE) was synthesized, consisting of zirconium metal coordinated with 1,1,2,2-tetrakis(4-carboxyphenyl) ethylene. YTU-G-1(SE) exhibits strong fluorescent properties with an aggregation-induced emission (AIE) effect, emitting yellow-green fluorescence at 515 nm. The internal and external quantum efficiencies (IQE/EQE) of YTU-G-1(SE) are close to unity, with values of 95.74 ± 0.5% and 88.67 ± 0.5%, respectively. Finally, we combined YTU-G-1(SE) with a commercial blue chip and a commercial red phosphor (Sr,Ca)AlSiN3:Eu2+ to fabricate a warm white light LED with a color temperature of 3736 K, a color-rendering index Ra of 88.2, and a lumen efficiency of 79.42 lm W-1. This work provides a new approach to regulating the emission of AIE and offers a novel idea for developing high-performance warm-white pc-WLEDs.

5.
J Biomech ; 163: 111937, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38246010

RESUMO

Transjugular intrahepatic portosystemic shunt (TIPS) relieves cirrhotic complications by reducing portacaval pressure gradient (PCG), but it lacks precision in achieving a targeted post-TIPS PCG simply through diameter adjustment of equal diameter stents. This study aimed to present a controlled-expansion, streamlined, and covered tapered stent, and examined its effects on pressure reduction compared with equal- diameter stents. Twenty-four patients who underwent standardized 8-mm stent TIPS implantation at West China Hospital from December 2017 to February 2021 were included in the current study. Virtual equal-diameter stent graft with different diameter and streamlined tapered stents were created in the post-TIPS 3-dimentional models reconstructed based on computed tomography angiography data. The numerical simulation showed that only two patients achieved targeted post-TIPS PCG consistent with the clinical invasive measurement. When 6-mm and 10-mm equal-diameter stents were employed, simulated post-TIPS PCGs for most patients remained outside the safe range, and recirculating flow was observed at the stent-portal vein anastomosis. In contrast, the use of the new streamlined taper stent resulted in post-TIPS PCGs within the 10-12 mmHg range for 17 out of 24 patients, with no recirculating flow observed at the anastomotic sites. In conclusion, the streamlined tapered stent could pose an effective solution to the problem that the big jump depressurization between two different equal-diameter stents and it would improve the hemodynamics in the region near the PV-stent anchorage. Therefore, the streamlined tapered stent may present a superior alternative for TIPS procedure.


Assuntos
Hipertensão Portal , Derivação Portossistêmica Transjugular Intra-Hepática , Humanos , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Resultado do Tratamento , Stents , Veia Porta
6.
Abdom Radiol (NY) ; 49(2): 575-585, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37980601

RESUMO

PURPOSE: The association between the presence of sarcopenia in patients with cirrhosis and the onset of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) is yet to be established. We conducted a systematic review and meta-analysis to provide a thorough summary of the available evidence on this association. METHODS: A thorough search of the literature was performed in the PubMed, EMBASE, and Web of Science databases. The protocol was duly registered on PROSPERO (CRD42023398856). The hazard ratio (HR) and corresponding 95% confidence intervals (CIs) for the occurrence of HE after TIPS were extracted from studies comparing cirrhotic patients with and without sarcopenia. These data were then combined using a random-effect model. RESULTS: A total of 1135 patients from seven cohort studies that met our eligibility criteria were included in the meta-analysis. Our findings indicate a significantly higher risk of post-TIPS HE among cirrhotic patients with sarcopenia compared to those without sarcopenia (HR, 2.35; 95% CIs 1.32-4.19; p = 0.004; I2 = 75%). The findings remained consistent across subgroups stratified by liver disease etiology, study location, and severity of hepatic dysfunction. CONCLUSION: The study demonstrated that sarcopenia was strongly linked to an increased likelihood post-TIPS HE among cirrhotic patients.


Assuntos
Encefalopatia Hepática , Derivação Portossistêmica Transjugular Intra-Hepática , Sarcopenia , Humanos , Encefalopatia Hepática/complicações , Encefalopatia Hepática/epidemiologia , Sarcopenia/complicações , Sarcopenia/diagnóstico por imagem , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
7.
Adv Mater ; 35(52): e2309413, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37950585

RESUMO

X-ray imaging plays an increasingly crucial role in clinical radiography, industrial inspection, and military applications. However, current X-ray imaging technologies have difficulty in protecting against information leakage caused by brute force attacks via trial-and-error. Here high-confidentiality X-ray imaging encryption by fabricating ultralong radioluminescence memory films composed of lanthanide-activated nanoscintillators (NaLuF4 : Gd3+ or Ce3+ ) with imperceptible purely-ultraviolet (UV) emission is reported. Mechanistic investigations unveil that ultralong X-ray memory is attributed to the long-lived trapping of thermalized charge carriers within Frenkel defect states and subsequent slow release in the form of imperceptible radioluminescence. The encrypted X-ray imaging can be securely stored in the memory film for more than 7 days and optically decoded by perovskite nanocrystal. Importantly, this encryption strategy can protect X-ray imaging information against brute force trial-and-error attacks through the perception of lifetime change in the persistent radioluminescence. It is further demonstrated that the as-fabricated flexible memory film enables achieving of 3D X-ray imaging encryption of curved objects with a high spatial resolution of 20 lp/mm and excellent recyclability. This study provides valuable insights into the fundamental understanding of X-ray-to-UV conversion in nanocrystal lattices and opens up a new avenue toward the development of high-confidential 3D X-ray imaging encryption technologies.

8.
J Environ Sci (China) ; 134: 108-116, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37673525

RESUMO

Nowadays, ozone contamination becomes dominant in air and thus challenges the research and development of cost-effective catalyst. In this study, metal doped Cu2O catalysts are synthesized via reduction of Cu2+ by ascorbic acid in base solutions containing doping metal ions. The results show that compared with pure Cu2O, the Mg2+ and Fe2+ dopants enhance the O3 removal efficiency while Ni2+ depresses the activity. In specific, Mg-Cu2O shows high O3 removal efficiency of 88.4% in harsh environment of 600,000 mL/(g·hr) space velocity and 1500 ppmV O3, which is one of the highest in the literature. Photoluminescence and electron paramagnetic spectroscopy characterization shows higher concentration of crystal defects induced by the Mg2+ dopants, favoring the O3 degradation. The in-situ diffuse reflectance Fourier transform infrared spectroscopy shows the intermediate species in the O3 degradation process change from O22- dominant of pure Cu2O to O2- dominant of Mg-Cu2O, which would contribute to the high activity. All these results show the promising prospect of the Mg-Cu2O for highly efficiency O3 removal.


Assuntos
Nanopartículas , Ozônio , Ácido Ascórbico , Metais , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Heliyon ; 9(7): e17884, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539111

RESUMO

Herein, we propose a simple and effective strategy for designing a zeolitic imidazolate frameworks (ZIFs) fluorescent probe with a two-dimensional leaf-like structure. By doping ZIF-L with phosphate, we developed a fluorescent probe for iron (Fe3+) in systems with high salinity. The fluorescence of P-ZIF-L was quenched effectively with the presence of Fe3+. The physicochemical structure, surface morphology, selectivity, stability and composition of the probe were investigated. Under optimized conditions, the fluorescent probe had a detection limit of 0.5 µM. Furthermore, the results that the probe exhibited desirable salt-tolerance and was suitable for determination of Fe3+ in brine water samples with satisfactory results.

11.
Radiology ; 308(2): e223201, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37606572

RESUMO

Background Some studies have shown that transjugular intrahepatic portosystemic shunt (TIPS) placement within 72 hours of admission improves survival in patients at high risk who present with acute variceal bleeding. However, the role of small-diameter covered TIPS in the secondary prophylaxis of variceal bleeding is still debatable. Purpose To compare the efficacy of 8-mm TIPS and endoscopic variceal ligation (EVL) plus propranolol in the prevention of variceal rebleeding among participants with advanced cirrhosis. Materials and Methods Between June 2015 and December 2018, participants admitted to the hospital for variceal bleeding were considered for enrollment in this randomized controlled trial (ClinicalTrials.gov). Participants with Child-Pugh class B or C cirrhosis were randomly assigned to receive an 8-mm covered TIPS or EVL and propranolol. The primary end point was recurrent variceal bleeding assessed using Kaplan-Meier curve analysis. Secondary end points included survival and overt hepatic encephalopathy (HE) assessed using Kaplan-Meier curve analysis. Results A total of 100 participants were enrolled, with 50 randomly assigned to the EVL plus propranolol group (median age, 54 years; IQR, 45-60 years; 29 male, 21 female) and 50 randomly assigned to the TIPS group (median age, 49 years; IQR, 43-56 years; 32 male, 18 female). The median follow-up period was 43.4 months. In the TIPS group, variceal rebleeding risk was reduced compared with variceal rebleeding risk in the EVL plus propranolol group (hazard ratio [HR], 0.31; 95% CI: 0.14, 0.69; P = .008), but the incidence of overt HE was higher in the TIPS group (30.0% vs 16.0%, P = .03). No differences in survival were observed between the two groups (1-year survival: TIPS, 98.0%; EVL plus propranolol, 92.0%; 3-year survival: TIPS, 94.0%; EVL plus propranolol, 85.7%; HR, 0.52; 95% CI: 0.19, 1.42; P = .22). Conclusion When compared with EVL plus propranolol, 8-mm TIPS led to reduced variceal rebleeding but did not impact overall survival in participants with Child-Pugh class B or C cirrhosis. Clinical trial registration no. NCT02477384 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Barth in this issue.


Assuntos
Varizes Esofágicas e Gástricas , Derivação Portossistêmica Transjugular Intra-Hepática , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Propranolol/uso terapêutico , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/prevenção & controle , Hemorragia Gastrointestinal/cirurgia , Cirrose Hepática/complicações
13.
Med Phys ; 50(10): 6614-6623, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37227701

RESUMO

BACKGROUND: It was still controversial that whether the increase of splenic vein (SV) diameter increased the risk of portal vein thrombosis (PVT), which was a severe disease with high mortality, in the clinic. PURPOSES: This study, using computational fluid dynamics method, aimed to investigate how the increase of SV diameter affects the portal vein hemodynamics under different anatomical and geometric features of the portal venous system, thus how it induced to PVT. METHODS: The ideal models of the portal system, including different anatomical structures according to the location of left gastric vein (LGV) and inferior mesenteric vein (IMV), and different geometric morphological parameters models were established to carry out numerical simulation in this study. In addition, the morphological parameters of real patients were measured to verify the numerical simulation results. RESULTS: First, the wall shear stress (WSS) and helicity intensity, which were closely related to the occurrence of thrombosis, gradually decreased with the increase of SV diameter in all models. However, the degree of decrease was bigger in following models: (1) the models with LGV and IMV linking to SV compared with them linking to PV; (2) the models with big angle of PV and SV compared with small angle. In addition, the morbidity of PVT was higher when LGV and IMV linked to SV rather than them linked to PV in the real patients. Moreover, the angle of PV and SV was also different between PVT and non-PVT patients (125.53° ± 16.90° vs. 115.03° ± 16.10°, p = 0.01). CONCLUSION: Whether the increase of SV diameter will result in PVT is depended on the anatomical structure of portal system and the angle between PV and SV, this is also the reason leading to the clinical controversy that the increase of SV diameter is the risk factor of PVT.


Assuntos
Trombose , Trombose Venosa , Humanos , Veia Porta/diagnóstico por imagem , Veia Porta/patologia , Veia Esplênica/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagem , Cirrose Hepática , Trombose/diagnóstico por imagem , Trombose/complicações , Estudos Retrospectivos
14.
Inorg Chem ; 62(16): 6421-6427, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37039382

RESUMO

With the growing demand for X-ray imaging, especially for three-dimensional objects with curved surfaces, a large-area flexible X-ray imaging membrane based on scintillating materials becomes the focus of vigorous investigation. Among the developed scintillators, metal-organic frameworks (MOFs) featuring tunable photophysical properties and marked luminescence stability hold great promise for serving as ideal X-ray scintillators. Here, we report a flexible composite scintillating membrane with superior imaging performance. The membrane is achieved by embedding an aggregation-induced emission (AIE) luminogen (AIEgen, H4ETTC)-functionalized MOF scintillator (Y-PCN-94) into a polymer matrix (PDMS). Notably, Y-PCN-94 exhibits a strong AIE effect under both ultraviolet (UV) light and X-ray irradiation, which is also the first time that the AIE effect was observed in the MOF system under an ionizing radiation field. This also gives the material promising radioluminescence properties, such as a low X-ray detection limit (1.6 µGy s-1) and high imaging resolution (>14.3 lp mm-1), which can be mainly attributed to the combination of the AIE effect and strong X-ray stopping power. This work demonstrates that incorporating AIEgens into MOFs or other frameworks can offer an alternative approach for producing high-performance X-ray scintillators.

15.
Neurosci Lett ; 803: 137194, 2023 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-36931592

RESUMO

Alzheimer's disease (AD), a neurodegenerative disease affecting the elderly, frequently causes cognitive impairment and memory decline, and there are currently no effective therapeutic drugs available. Glutamate excitotoxicity is one of the pathogeneses of AD, and there is evidence that glutamic-oxaloacetic transaminase (GOT) can significantly reduce glutamate concentrations in the hippocampi of mice, but its role in APP/PS1 transgenic mice is unknown. We investigated the improvement of neurological function and related protein expression following subcutaneous injection of GOT in mice with AD. We performed immunohistochemical staining on the brain tissue of 3-, 6-, and 12-month-old mice and found that the content of the ß-amyloid protein Aß1-42 in the 6 months old GOT treatment group was significantly reduced. Meanwhile, the APP-GOT group outperformed the APP group in the water maze and spatial object recognition experiments. The number of neurons in the hippocampal CA1 area of the APP-GOT group increased when compared to the APP group according to Nissl staining. Electron microscopic examination of the hippocampal CA1 area demonstrated that the number of synapses in the APP-GOT group was more than that in the APP group, and the mitochondrial structure was relatively complete. Finally, the protein content of the hippocampus was detected. In comparison to the APP group, SIRT1 content increased in the APP-GOT group whereas Aß1-42 content decreased, and Ex527 could reverse this trend. These results suggest that GOT can significantly improve the cognitive function of mice in the early stage of AD, and the underlying mechanism may be through decreasing Aß1-42 and increasing SIRT1 expressions.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Camundongos , Animais , Doença de Alzheimer/metabolismo , Sirtuína 1/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Doenças Neurodegenerativas/metabolismo , Aspartato Aminotransferases/metabolismo , Hipocampo/metabolismo , Peptídeos beta-Amiloides/metabolismo , Camundongos Transgênicos , Neurônios/metabolismo , Modelos Animais de Doenças , Presenilina-1/metabolismo , Camundongos Endogâmicos C57BL
17.
Research (Wash D C) ; 6: 0090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37000186

RESUMO

Organic scintillators, materials with the ability to exhibit luminescence when exposed to X-rays, have aroused increasing interest in recent years. However, the enhancement of radioluminescence and improving X-ray absorption of organic scintillators lie in the inherent dilemma, due to the waste of triplet excitons and weak X-ray absorption during scintillation. Here, we employ halogenated thermally activated delayed fluorescence materials to improve the triplet exciton utilization and X-ray absorption simultaneously, generating efficient scintillation with a low detection limit, which is one order of magnitude lower than the dosage for X-ray medical diagnostics. Through experimental study and theoretical calculation, we reveal the positive role of X-ray absorption, quantum yields of prompt fluorescence, and intersystem crossing in promoting the radioluminescence intensity. This finding offers an opportunity to design diverse types of organic scintillators and expands the applications of thermally activated delayed fluorescence.

18.
Dig Dis Sci ; 68(7): 3185-3192, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36715817

RESUMO

BACKGROUND AND AIMS: The selection of appropriate candidates for transjugular intrahepatic portosystemic shunt (TIPS) is important and challenging. To validate the Model for End-Stage Liver Disease (MELD) 3.0 in predicting mortality in patients with cirrhosis after TIPS creation. METHODS: A total of 855 consecutive patients with cirrhosis from December 2011 to October 2019 who underwent TIPS placement were retrospectively reviewed. The prognostic value of the MELD 3.0, MELD, MELD-Na, Child-Pugh and FIPS score was assessed using Harrell's C concordance index (c-index). The Hosmer-Lemeshow test was used to test the goodness of fit of all models and the calibration plot was drawn. RESULTS: The c-index of the MELD 3.0 in predicting 3-month mortality was 0.727 (0.645-0.808), which were significantly superior to the MELD (0.663 [0.565-0.761]; P = 0.015), MELD-Na (0.672 [0.577-0.768]; P = 0.008) and FIPS (0.582 [0.477-0.687]; P = 0.015). The Child-Pugh score reached c-indices of 0.754 (0.673-0.835), 0.720 (0.649-0.792), 0.705 (0.643-0.766) and 0.665 (0.614-0.716) for 3-month, 6-month, 1-year, and 2-year mortality, respectively, which seems comparable to MELD 3.0. A MELD 3.0 of 14 could be used as a cut-off point for discriminating between high- and low-risk patients. The MELD 3.0 could stratify patients with Child-Pugh grade B (log-rank P < 0.001). The Child-Pugh score could stratify patients defined as low risk by MELD 3.0 (log-rank P < 0.001). CONCLUSIONS: The MELD 3.0 was significantly superior to the MELD, MELD-Na and FIPS scores in predicting mortality in patients with cirrhosis after TIPS creation.


Assuntos
Doença Hepática Terminal , Derivação Portossistêmica Transjugular Intra-Hepática , Humanos , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Estudos Retrospectivos , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/cirurgia , Doença Hepática Terminal/etiologia , Índice de Gravidade de Doença , Cirrose Hepática/diagnóstico , Cirrose Hepática/cirurgia , Cirrose Hepática/etiologia , Resultado do Tratamento
20.
Int Immunopharmacol ; 114: 109540, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36516541

RESUMO

BACKGROUND: Autoimmune hepatitis (AIH) is an inflammatory liver disease that is associated with impaired self-tolerance. Myeloid-derived supprfessor cells (MDSCs) have been considered to exert counterregulatory effects on AIH. However, the specific mechanism underlying these effects is unclear. Herein, we investigated the efficacy and safety of MDSCs in protecting against AIH and explored the underlying mechanism. METHODS: Circulating and liver MDSC expression levels in 71 AIH patients and 47 healthy control (HC) individuals were detected by flow cytometry and immunohistochemistry. The adoptive transfer of induced bone marrow-derived MDSCs (BM MDSCs) to AIH mice was used to explore the function of MDSCs. Hepatic injury and mitochondrial damage were evaluated by transaminase levels, histopathology, immunohistochemistry, transmission electron microscopy and western blotting. MDSCs were pretreated with the small extracellular vesicle (sEV) generation inhibitor GW4869 to explore the mechanism. Importantly, sEVs derived from MDSCs and MDSCs-GW4869 were injected into model mice to monitor mitochondrial function and biogenesis. RESULTS: Circulating and liver MDSCs were expanded in AIH patients and mouse model. Furthermore, the follow-up data of AIH patients showed that immunosuppressive therapy further promoted the expansion of MDSCs. More importantly, the adoptive transfer of BM MDSCs to AIH mice effectively ameliorated liver injury and regulated the imbalance of the immune microenvironment. Additionally, BM MDSCs reduced liver mitochondrial damage and improved mitochondrial biogenesis. Mechanistically, sEVs derived from BM MDSCs showed the same biological effects as cells, and blocking sEV production weakened the function of BM MDSCs. Finally, multiple long-term administrations of BM MDSCs were proven to be safe in general. CONCLUSION: In conclusion, MDSCs ameliorate liver mitochondrial damage to protect against autoimmune hepatitis by releasing small extracellular vesicles.


Assuntos
Vesículas Extracelulares , Hepatite Autoimune , Células Supressoras Mieloides , Animais , Camundongos , Hepatite Autoimune/terapia , Mitocôndrias/patologia , Vesículas Extracelulares/metabolismo , Camundongos Endogâmicos C57BL
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