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1.
Anal Chem ; 96(5): 2041-2051, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38270108

RESUMO

Ferroptosis is critical in the treatment of tumor therapies. Thus, monitoring reactive oxygen species (ROS) is of great significance for accurate assessment in ferroptosis without any interference. However, current probes for monitoring ROS during ferroptosis suffer from a drawback in that the probes consume ROS during detection, which inhibits the ferroptosis process and thus affects the accuracy and effectiveness of monitoring the process of ferroptosis. Herein, a new fluorescent donor probe, TFMU-SO2D, with the combination of the moiety of the SO2 donor is designed and synthesized by introducing the aryl boronate moieties that could give it the ability to effectively recognize ONOO-. The released SO2 could consume excess glutathione and regulate oxidative stress by elevating ROS levels, which would offset the ROS depletion by TFMU-SO2D and ensure accuracy in monitoring the ferroptosis process. The experimental results demonstrated that TFMU-SO2D possessed satisfactory performance for monitoring ONOO- as well as simultaneously releasing SO2 in oxidative stress stimulated by monensin and ferroptosis stimulated by erastin and RSL3. Additionally, the capability of SO2 synergized with ferroptosis to inhibit the viability of cancer cells was demonstrated by the CCK8 assay, which may be due to the fact that SO2 can potentiate ferroptosis cell death by increasing the ROS level. Overall, these combined results indicated that TFMU-SO2D possesses the excellent ability to precisely monitor ONOO- during ferroptosis without interference, which is significant for accurately accessing ferroptosis, cancer treatment, and drug development.


Assuntos
Ferroptose , Dióxido de Enxofre , Espécies Reativas de Oxigênio/metabolismo , Morte Celular , Estresse Oxidativo
2.
Small ; 20(8): e2306267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37840405

RESUMO

Heteroatom-doped layered porous carbons are recently regarded as promising electrode materials for high energy density supercapacitors because they can integrate high-level heteroatom-doping and layered nano-space together to provide huge pseudocapacitive reaction areas and accelerate ion diffusion/transport. Herein, an innovative strategy is reported to prepare N/B/O co-doped layered porous carbons via ammonium folate-reinforced self-assembly of gelatin and boric acid followed by carbonization. Biomass-derived ammonium folate not only acts as an N-riched precursor but also can fasten in the process of self-assembly via boric acid-assisted electrostatic adsorption and hydrogen bonding to promote the formation of stable 3D cross-linked networks, resulting in the obtained N/B/O co-doped layered porous carbon (BNLC-850) has a large specific surface area (1822 m2 g-1 ), hierarchical porous structure and super-high heteroatom contents (N, 12.65; B, 5.67; and O, 13.84 at.%). The BNLC-850 achieves an ultrahigh specific capacitance of 525.2 F g-1 in the alkaline electrolyte at 0.5 A g-1 , meanwhile, DFT calculations reveal that the high-level N/B/O-doping can effectively weaken the adsorption barriers of K-ions. Moreover, the BNLC-850 assembles anti-freezing flexible solid-state supercapacitors in MPEI-TF-IL gel polymer electrolyte deliver a high energy density of 41.2 Wh kg-1 , excellent flexibility, and long cycle-life at -20 °C.

3.
Small ; : e2401256, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752227

RESUMO

Nickel oxide (NiOx) is a promising hole transport layer (HTL) to fabricate efficient and large-scale inverted perovskite solar cells (PSCs) due to its low cost and superior chemical stability. However, inverted PSCs based on NiOx are still lagging behind that of other HTL because of the poor quality of buried interface contact. Herein, a bidentate ligand, 4,6-bis (diphenylphosphino) phenoxazine (2DPP), is used to regulate the NiOx surface and perovskite buried interface. The diphosphine Lewis base in the 2DPP molecule can coordinate both with NiOx and lead ions at NiOx/perovskite interface, leading to high-quality perovskite films with minimized defects. It is found that the inverted PSCs with 2DPP-modified buried interface exhibit double advantages of being both fast charge extraction and reduced nonradiative recombination, which is a combination of multiple factors including favorable energetic alignment, improved interface contact and strong binding between NiOx/2DPP and perovskite. The optimal PSC based on 2DPP modification yields a champion power conversion efficiency (PCE) of 21.9%. The unencapsulated PSC maintains above 75% of its initial PCE in the air with a relative humidity (RH) of 30-40% for 1000 h.

4.
Opt Lett ; 49(1): 105-108, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134156

RESUMO

In this study, we propose a pioneering spatially frequency-shifted super-resolution microscopy technique that utilizes the synergy of quasiperiodic gratings and deep learning. First, a quasiperiodic grating capable of converting evanescent waves into propagating waves is designed. The grating is positioned between the object under investigation and the objective lens, and the high-frequency information carried by the evanescent waves in the near-field region of the object is shifted into the detection window and becomes accessible in the far field for imaging. Subsequently, we provide two deep learning models for image and video reconstructions to achieve the reconstruction of static and dynamic samples respectively. Simulation results demonstrate the high feasibility of the proposed method, and both static and dynamic objects with sub-wavelength features can be resolved. The developed method paves the way to the realization of super-resolution imaging by using a traditional bright-field microscope without the need for an extensive optical system design.

5.
Chemistry ; 30(10): e202302768, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38171767

RESUMO

Fe2 O3 with high theoretical capacity (1007 mA h g-1 ) and low cost is a potential anode material for lithium-ion batteries (LIBs), but its practical application is restricted by its low electrical conductivity and large volume changes during lithiation/delithiation. To solve these problems, Fe2 O3 @Ti3 C2 Tx composites were synthesized by a mussel-like modification method, which relies on the self-polymerization of dopamine under mild conditions. During polymerization, the electronegative group (-OH) on dopamine can easily coordinate with Fe3+ ions as well as form hydrogen bonds with the -OH terminal group on the surface of Ti3 C2 Tx , which induces a uniform distribution of Fe2 O3 on the Ti3 C2 Tx surface and mitigates self-accumulation of MXene nanosheets. In addition, the polydopamine-derived carbon layer protects Ti3 C2 Tx from oxidation during the hydrothermal process, which can further improve the electrical conductivity of the composites and buffer the volume expansion and particle agglomeration of Fe2 O3 . As a result, Fe2 O3 @Ti3 C2 Tx anodes exhibit ~100 % capacity retention with almost no capacity loss at 0.5 A g-1 after 250 cycles, and a stable capacity of 430 mA h g-1 at 2 A g-1 after 500 cycles. The unique structural design of this work provides new ideas for the development of MXene-based composites in energy storage applications.

6.
BMC Infect Dis ; 24(1): 257, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395803

RESUMO

PURPOSE: To identify the key infection processes and risk factors in Computed Tomography (CT) examination process within the standard prevention and control measures for the COVID-19 epidemic, aiming to mitigate cross-infection occurrences in the hospital. METHOD: The case hospital has assembled a team of 30 experts specialized in CT examination. Based on the CT examination process, the potential failure modes were assessed from the perspective of severity (S), occurrence probability (O), and detectability (D); they were then combined with corresponding risk prevention measures. Finally, key infection processes and risk factors were identified according to the risk priority number (RPN) and expert analysis. RESULTS: Through the application of RPN and further analysis, four key potential infection processes were identified, including "CT request form (A1)," "during the scan of CT patient (B2)," "CT room and objects disposal (C2)," and "medical waste (garbage) disposal (C3)". In addition, eight key risk factors were also identified, including "cleaning personnel does not wear masks normatively (C32)," "nurse does not select the vein well, resulting in extravasation of the peripheral vein for enhanced CT (B25)," "patient cannot find the CT room (A13)," "patient has obtained a CT request form but does not know the procedure (A12)," "patient is too unwell to continue with the CT scan (B24)," "auxiliary staff (or technician) does not have a good grasp of the sterilization and disinfection standards (C21)," "auxiliary staff (or technician) does not sterilize the CT machine thoroughly (C22)," and "cleaning personnel lacks of knowledge of COVID-19 prevention and control (C33)". CONCLUSION: Hospitals can publicize the precautions regarding CT examination through various channels, reducing the incidence of CT examination failure. Hospitals' cleaning services are usually outsourced, and the educational background of the staff employed in these services is generally not high. Therefore, during training and communication, it is more necessary to provide a series of scope and training programs that are aligned with their understanding level. The model developed in this study effectively identifies the key infection prevention process and critical risk factors, enhancing the safety of medical staff and patients. This has significant research implications for the potential epidemic of major infectious diseases.


Assuntos
COVID-19 , Infecção Hospitalar , Humanos , Infecção Hospitalar/prevenção & controle , Fatores de Risco , Tomografia Computadorizada por Raios X , Tomografia
7.
J Fluoresc ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38676771

RESUMO

As one of the most significant parameters in cellular microenvironment, viscosity levels could be used to determine the metabolic process of bioactive substances within cells. Abnormal viscosity levels are closely associated with a series of diseases. Therefore, the design and synthesis of fluorescent probes that can monitor changes of intracellular viscosity in real-time is of great significance for the study of disease development process. Here, a new viscosity-recognized NIR fluorescence probe W1 based on quinoline-malonitrile is synthesized, and it is not susceptible to interference substances. Besides, AIE probe W1 shows fast response, excellent photostability, low cytotoxicity, good linear relationship between fluorescence intensity value and viscosity. Based on the above advantages, probe W1 is used to image the change of viscosity level in the cell model induced by nystatin.

8.
Nature ; 559(7715): 637-641, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30022161

RESUMO

Diabetes is a complex metabolic syndrome that is characterized by prolonged high blood glucose levels and frequently associated with life-threatening complications1,2. Epidemiological studies have suggested that diabetes is also linked to an increased risk of cancer3-5. High glucose levels may be a prevailing factor that contributes to the link between diabetes and cancer, but little is known about the molecular basis of this link and how the high glucose state may drive genetic and/or epigenetic alterations that result in a cancer phenotype. Here we show that hyperglycaemic conditions have an adverse effect on the DNA 5-hydroxymethylome. We identify the tumour suppressor TET2 as a substrate of the AMP-activated kinase (AMPK), which phosphorylates TET2 at serine 99, thereby stabilizing the tumour suppressor. Increased glucose levels impede AMPK-mediated phosphorylation at serine 99, which results in the destabilization of TET2 followed by dysregulation of both 5-hydroxymethylcytosine (5hmC) and the tumour suppressive function of TET2 in vitro and in vivo. Treatment with the anti-diabetic drug metformin protects AMPK-mediated phosphorylation of serine 99, thereby increasing TET2 stability and 5hmC levels. These findings define a novel 'phospho-switch' that regulates TET2 stability and a regulatory pathway that links glucose and AMPK to TET2 and 5hmC, which connects diabetes to cancer. Our data also unravel an epigenetic pathway by which metformin mediates tumour suppression. Thus, this study presents a new model for how a pernicious environment can directly reprogram the epigenome towards an oncogenic state, offering a potential strategy for cancer prevention and treatment.


Assuntos
Adenilato Quinase/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/metabolismo , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animais , DNA/química , DNA/metabolismo , Metilação de DNA , Diabetes Mellitus/genética , Dioxigenases , Estabilidade Enzimática , Epigênese Genética , Hemoglobinas Glicadas/análise , Humanos , Hiperglicemia/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fosforilação , Fosfosserina/metabolismo , Especificidade por Substrato , Ensaios Antitumorais Modelo de Xenoenxerto
9.
BMC Anesthesiol ; 24(1): 59, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336616

RESUMO

BACKGROUND: This study assessed the impact of pressure-controlled ventilation (PCV) focusing on end-inspiratory flow rate on the incidence of postoperative pulmonary complications (PPCs) and inflammation levels in patients undergoing spinal surgery in the prone position. METHODS: A total of 187 patients who underwent posterior spinal surgery were enrolled and randomly divided into 3 groups: 61 in the volume-controlled ventilation (VCV) group (group V), 62 in the PCV-volume-guaranteed (VG) group (group P1), and 64 in the PCV-VG end-expiratory zero flow rate group (group P2). Indicators including tidal volume (VT), peak airway pressure (Ppeak), and dynamic lung compliance (Cdyn) were recorded. The Ppeak, Cdyn, PETCO2, and oxygenation index (PaO2/FiO2) after intubation (T0), after prone position (T1), 60 min after prone position (T2), and after supine position at the end of surgery (T3) of the three groups were collected. RESULTS: In the within-group comparison, compared with T0, Ppeak increased at T1 - 2 in groups V and P1 (P < 0.01), whereas it decreased at T1 - 3 in group P2 (P < 0.01). Cdyn decreased at T1 - 2 and PaO2/FiO2 increased at T1 - 3 in all three groups (P < 0.01), and PaO2/FiO2 increased at T1 - 3 (P < 0.01). Compared with group V, Ppeak decreased at T0 - 3 in group P1 (P < 0.01) and at T1 - 3 in group P2 (P < 0.01), while Cdyn increased at T0 - 3 in groups P1 and P2 (P < 0.01). Compared with group P1, Ppeak was elevated at T0 (P < 0.01) and decreased at T1 - 3 (P < 0.05), and Cdyn was elevated at T0 - 3 in group P2 (P < 0.01). The total incidence of PPCs in group P2 was lower than that in group V (P < 0.01). Compared with the preoperative period, serum interleukin 6 (IL-6) and C-reactive protein (CRP) levels were increased at 24 and 72 h after surgery in group V (P < 0.01), whereas that was increased at 24 h after surgery in group P1 and group P2 (P < 0.01). Compared with group V, serum IL-6 and CRP levels were reduced at 24 h after surgery in groups P1 and P2 (P < 0.01 or < 0.05). CONCLUSION: In patients undergoing spinal surgery in the prone position, PCV-VG targeting an end-inspiratory zero flow rate lowers the incidence of PPCs and inflammation levels.


Assuntos
Interleucina-6 , Síndrome do Desconforto Respiratório , Humanos , Decúbito Ventral , Respiração Artificial , Volume de Ventilação Pulmonar
10.
J Sci Food Agric ; 104(2): 942-955, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37708388

RESUMO

BACKGROUND: Nutritional and functional qualities and applications of structured lipids (SL) depend on the composition and molecular structure of fatty acids in the glycerol backbone of triacylglycerol (TAG). However, the relationship between the substrate composition and physicochemical qualities of SL has not been revealed. The investigation aims to disclose the effect of substrate composition on the physicochemical properties of medium-long-medium structured lipids (MLM-SLs) by enzymatic interesterification of Lipozyme TLIM/RMIM. RESULTS: The medium-long-chain triacylglycerol (MLCT) yield could reach 70.32%, including 28.98% CaLCa (1,3-dioctonyl-2-linoleoyl glyceride) and 24.34% CaOCa (1,3-didecanoyl-2-oleoyl glyceride). The sn-2 unsaturated fatty acid composition mainly depended on long-chain triacylglycerol (LCT) in the substrate. The increased carbon chain length and double bond in triacylglycerol decreased its melting and crystallization temperature. The balanced substrate composition of MCT/LCT increased the size and finer crystals. Molecular docking simulation revealed that the MLCT molecule mainly interacted with the catalytic triplets of Lipozyme TLIM (Arg81-Ser83-Arg84) and the Lipozyme RMIM (Tyr183-Thr226-Arg262) by OH bond. The oxygen atom of the ester on the MLCT molecule was primarily bound to the hydrogen of hydroxyl and amino groups on the binding sites of Lipozyme TLIM/RMIM. The intermolecular interplay between MLCT and Lipozyme RMIM is more stable than Lipozyme TLIM due to the formation of lower binding affinity energy. CONCLUSION: This research clarifies the interaction mechanism between MLCT molecules and lipases, and provides an in-depth understanding of the relationship between substrate composition, molecular structure and physicochemical property of MLM-SLs. © 2023 Society of Chemical Industry.


Assuntos
Ácidos Graxos , Triglicerídeos/química , Simulação de Acoplamento Molecular , Ácidos Graxos/química
11.
Esophagus ; 21(2): 131-140, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38194013

RESUMO

BACKGROUND: Esophageal squamous cell neoplasms (ESCNs) are common second primary tumors in patients with head and neck cancer. Image-enhanced endoscopy (IEE) with Lugol chromoendoscopy or magnifying narrow-band imaging both increase the detection of early ESCNs. No evidence-based ESCN surveillance program for head and neck cancer patients without a history of synchronous ESCNs exists. We aimed to evaluate the performance of an IEE surveillance program with magnifying narrow-band imaging endoscopy and Lugol chromoendoscopy. METHODS: From April 2016, we routinely used IEE with magnifying narrow-band imaging and Lugol chromoendoscopy to evaluate patients with head and neck cancer history. All patients who were negative for ESCNs at the first surveillance endoscopy and received at least 2 IEEs through December 2019 were included. Demographic profiles, clinical data, cancer characteristics, IEE results and pathology reports were analyzed. RESULTS: A total of 178 patients were included. Only 4 patients (2.2%) developed metachronous ESCNs during follow-up, all of whom received curative resection treatment. The interval for the development of metachronous ESCNs was 477 to 717 days. In multivariate Firth logistic regression and Kaplan‒Meier survival curve analysis, Lugol's voiding lesion type C had an increased risk of esophageal cancer development (adjusted odds ratio = 15.71; 95% confidence interval, 1.33-185.87, p = 0.029). Eight patients died during the study period, and none of them had metachronous ESCNs. CONCLUSIONS: IEE with magnifying narrow-band imaging and Lugol chromoendoscopy is an effective surveillance program in head and neck cancer patients without a history of ESCNs. Annual surveillance can timely detect early ESCNs with low ESCN-related mortality.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Neoplasias de Cabeça e Pescoço , Segunda Neoplasia Primária , Humanos , Segunda Neoplasia Primária/diagnóstico , Esofagoscopia/métodos , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia
12.
Biochem Biophys Res Commun ; 639: 189-196, 2023 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-36535138

RESUMO

Heart failure is one of the major fatal diseases and mitochondrial biogenesis is an important compensatory mechanism in the process of heart failure. Aldehyde dehydrogenase 2(ALDH2) is an important endogenous cardiac protective factor in mitochondria, but its role in mitochondrial biogenesis of cardiomyocytes remains unknown. In our study, transverse aorta constriction(TAC)-induced heart failure model was established in ALDH2-/- mice and wild-type mice. The cardiac function was examined by echocardiography at 4 weeks after operation. The myocardial tissue was stained by HE. The mitochondria morphology was observed using electron microscope, and the ATP content, Sirt1,PGC-1α and NRF1 expression were measured. Compared with wild-type mice, the cardiac function of ALDH2 -/- mice decreased significantly at 4 weeks after TAC. The proportion of mitochondrial area and mitochondrial crest/mitochondrial ratio decreased in the ALDH2-/- group after TAC. The ATP content decreased in ALDH2 -/- mice at 4 weeks after TAC. In the meantime, the expression of PGC-1α,Sirt 1 and NRF1 decreased in the ALDH2-/- TAC group compared with wild type TAC group.Neonatal rat cardiomyocytes were cultured and stretched. Cardiomyocytes were treated with the activator of ALDH2(Alda-1), Sirt1-SiRNA and PGC-1α-siRNA, respectively. The mitochondrial structure of cardiomyocytes was observed by transmission electron microscopy. The levels of PGC-1α,NRF-1 and Tfam were measured by Western blot.Mitochondrial biogenesis was enhanced in stretch cardiomyocytes treated with Alda-1.When cardiomyocytes were treated with Sirt1-SiRNA or PGC1α-SiRNA, the effect of Alda-1 in promoting mitochondrial biogenesis was attenuated.Therefore, these results suggested that the loss of ALDH2 aggravates mitochondrial biogenesis disorder in cardiac myocytes induced by TAC. Alda-1 could promote mitochondrial biogenesis in stretched cardiomyocytes, and this effect depends on Sirt1/PGC-1α pathway.


Assuntos
Aldeído-Desidrogenase Mitocondrial , Insuficiência Cardíaca , Doenças Mitocondriais , Miócitos Cardíacos , Animais , Camundongos , Ratos , Trifosfato de Adenosina/metabolismo , Aldeído-Desidrogenase Mitocondrial/genética , Aldeído-Desidrogenase Mitocondrial/metabolismo , Insuficiência Cardíaca/metabolismo , Doenças Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Biogênese de Organelas , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Interferente Pequeno/metabolismo , Sirtuína 1/metabolismo
13.
Opt Express ; 31(5): 8641-8649, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859975

RESUMO

We present for the first time a surface plasmon-enhanced dark-field microsphere-assisted microscopy in imaging both low-contrast dielectric objects and metallic ones. We demonstrate, using an Al patch array as the substrate, the resolution and contrast in imaging low-contrast dielectric objects are improved compared to that of the metal plate substrate and a glass slide in dark-field microscopy (DFM). 365-nm-diameter hexagonally arranged SiO nanodots assembled on the three substrates can be resolved, with the contrast varied from 0.23 to 0.96, and the 300-nm-diameter hexagonally close-packed polystyrene nanoparticles can only be discerned on the Al patch array substrate. The resolution can be further improved by using the dark-field microsphere-assisted microscopy, and an Al nanodot array with a nanodot diameter of ∼65 nm and a center-to-center spacing of 125 nm can be just resolved, which cannot be distinguished in a conventional DFM. The focusing effect of the microsphere, as well as the excitation of the surface plasmons, provides evanescent illumination with enhanced local electric field (E-field) on an object. The enhanced local E-field acts as a near-field excitation source to enhance the scattering of the object, resulting in the improvement of imaging resolution.

14.
Opt Lett ; 48(7): 1858-1861, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221784

RESUMO

Here we find that a fully immersed low refractive index SiO2 microsphere (or a microcylinder, a yeast cell) can clearly distinguish a sample with sub-diffraction features in dark-field illumination mode. The resolvable area of the sample by microsphere-assisted microscopy (MAM) is composed of two regions. One region locates below the microsphere, and a virtual image of this part of the sample is formed by the microsphere first and then the virtual image is received by the microscope. The other region is around the edge of the microsphere, and this part of the sample is directly imaged by the microscope. The simulated region of the enhanced electric field on the sample surface formed by the microsphere is consistent with the resolvable region in the experiment. Our studies show that the enhanced electric field on the sample surface generated by the fully immersed microsphere plays an important role in dark-field MAM imaging, and this finding will have a positive effect on exploring novel mechanisms in resolution improvement of MAM.

15.
Chemistry ; 29(20): e202300027, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36620961

RESUMO

The allylic alcohol structural motif is prevalent in many important molecules and valuable building blocks. The rearrangement reaction is one of the most important transformations, however there are only a few reports for the 1,3-rearrangement of allylic alcohols. Herein, a 1,3-rearrangement of allylic alcohols catalyzed by an Ir(III) dihydride complex is described. This reaction could provide the corresponding less accessible allylic alcohols regio- and stereoselectively from readily available E/Z mixtures of the substrates. Furthermore, a tandem alkene isomerization followed by 1,3-rearrangement of homoallylic alcohols was also realized. In addition, this rearrangement reaction could be used to synthesize the natural product Navenone B. Mechanistic investigation indicated that the reaction pathway involved a π-allyl-Ir(V) intermediate and that the dihydride in the iridium catalyst acts as a hydrogen switch to modulate the valence of the iridium center.

16.
BMC Gastroenterol ; 23(1): 252, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491210

RESUMO

BACKGROUND: Periampullary diverticulum (PAD) may make the performance of endoscopic retrograde cholangiopancreatography (ERCP) in patients with choledocholithiasis more difficult and may increase complication rates. The present study evaluated the effects of PAD on first-time ERCP in patients with choledocholithiasis. METHODS: Outcomes were compared in patients with and without PAD and in those with four types of PAD: papilla located completely inside the diverticulum (type I), papilla located in the inner (type II a) and outer (type II b) margins of the diverticulum; and papilla located outside the diverticulum (type III). Parameters compared included cannulation time and rates of difficult cannulation, post-ERCP pancreatitis (PEP) and perforation. RESULTS: The median cannulation times in patients with types I, II a, II b, III PAD and in those without PAD were 2.0 min, 5.0 min, 0.67 min, 3.5 min, and 3.5 min, respectively, with difficult cannulation rates in these groups of 7.4%, 31.4%, 8.3%, 18.9%, and 23.2%, respectively. The rates of PEP in patients with and without PAD were 5.3% and 5.1%, respectively. Four patients with and one without PAD experienced perforation. CONCLUSIONS: The division of PAD into four types may be more appropriate than the traditional division into three types. Cannulation of type I and II b PAD was easier than cannulation of patients without PAD, whereas cannulation of type II a PAD was more challenging. PAD may not increase the rates of PEP.


Assuntos
Ampola Hepatopancreática , Coledocolitíase , Divertículo , Duodenopatias , Humanos , Coledocolitíase/etiologia , Cateterismo/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Duodenopatias/etiologia
17.
J Fluoresc ; 33(2): 401-411, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36480123

RESUMO

Anions and cations have a key role in our normal life. Cu2+ ion is a crucial trace element accountable for the part of several cellular enzymes and proteins, including cytochrome c oxidase, dopamine monooxygenase, Cu/Zn superoxide dismutase, and ceruloplasmin. WHO has found the extreme acceptable level of Cu2+ ions in drinking water is up to 2.0 ppm. Excess use of Cu2+ ions is associated with various human genetic disorders. Thus, the visualization of Cu2+ ions to avoid its toxic effects in chemical and biological systems is significant. In this review we have summarized sensors based on catalytic hydrolysis of picolinate to detect Cu2+ ions. The sensors based on hydrolysis of picolinate are very selective as compared to the other sensors for Cu2+ ions detection. We have focused on describing the structure, spectral properties, detection limits, and bioimaging model of the sensors.


Assuntos
Cobre , Corantes Fluorescentes , Humanos , Cobre/química , Hidrólise , Cátions , Corantes Fluorescentes/química
18.
Biomed Chromatogr ; 37(10): e5711, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37593807

RESUMO

Mallotus apelta leaf, recorded in the quality standard of Yao Medicinal Material in Guangxi Zhuang autonomous region, is commonly used in the treatment of liver diseases. Total flavonoids of M. apelta leaf (TFM) had good anti-fibrosis activity, but the anti-fibrosis mechanism of TFM is still unclear. Nuclear magnetic resonance technology was used to study the dynamic changes of urine metabolites in CCl4 -induced liver fibrosis before and after TFM treatment. Ingenuity Path Analysis (IPA) was used to find potential target genes for TFM to improve liver fibrosis and verify the expression of target genes by real-time fluorescent quantitative PCR and Western blotting. TFM can significantly reduce serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) levels, improve liver steatosis and reduce inflammation; in urine metabolomics, a total of seven potential biomarkers were found, mainly involving two metabolic pathways; IPA analysis showed that TNF may be a potential target for TFM to improve liver fibrosis induced by CCl4 in rats. This study found that TNF may be a potential target gene for TFM treatment of liver fibrosis, and shows that the anti-fibrosis mechanism of TFM could improve liver fibrosis by regulating the tricarboxylic acid cycle and subtaurine metabolism.


Assuntos
Tetracloreto de Carbono , Mallotus (Planta) , Animais , Ratos , Tetracloreto de Carbono/toxicidade , China , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Metabolômica , Flavonoides/farmacologia , Folhas de Planta
19.
J Sci Food Agric ; 103(1): 108-117, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35810339

RESUMO

BACKGROUND: Diacylglycerol (DAG)-enriched oil has been attracting attention because of its nutritional benefits and biological functions, although the composition of its various free fatty acids (FFAs) and an unclear relationship between substrate and yield make it difficult to be identified and qualified with respect to its production. In the present study, linoleic acid-enriched diacylglycerol (LA-DAG) was synthesized and enriched from Camellia oil by the esterification process using the combi-lipase Lipozyme TL IM/RM IM system. RESULTS: The relationship between FFA composition and DAG species productivity was revealed. The results showed that heterogeneous FFA with a major constituent (more than 50%) exhibited higher DAG productivity and inhibited triacylglycerol productivity compared to homogeneous constituents. Joint characterization by high-performance liquid chromatography-evaporative light scattering detection, gas chromatography-mass spectrometry and ultra-performance liquid chromatography-heated electrospray ionization-tandem mass spectrometry identified that DAG components contained dilinoleic acid acyl glyceride, linoleyl-oleyl glyceride and dioleic acid acyl glyceride in esterification products. Under the optimum conditions, 60.4% 1,3-DAG and 61.3% LA-DAG in the crude product at 1 h reaction were obtained, and further purified to 81.7% LA-DAG and 94.7% DAG via silica column chromatography. CONCLUSION: The present study provides a guideline for the identification of DAG species, as well as a structure-guided preparation method of DAG-enriched oils via the cost-effective combi-lipase. © 2022 Society of Chemical Industry.


Assuntos
Camellia , Diglicerídeos , Diglicerídeos/química , Ácido Linoleico , Lipase/química , Óleos de Plantas/química , Glicerídeos , Ácidos Graxos não Esterificados
20.
Rev Esp Enferm Dig ; 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37350651

RESUMO

Pancreatitis, panniculitis and polyarthritis syndrome (PPP syndrome) is a clinical syndrome with cutaneous panniculitis and polyarthritis on the basis of pancreatic diseases, which is quite rare. The occurrence of arthrosis and skin lesions is not completely synchronous with pancreatic diseases, so it is often missed or misdiagnosed due to the lack of obvious abdominal signs, with severe sequelae and high mortality. In this article, we report a case of PPP syndrome with severe rare osseous complications caused by chronic pancreatitis.

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