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1.
Sensors (Basel) ; 24(11)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38894263

RESUMEN

In order to improve the efficiency and accuracy of multitarget detection of soldering defects on surface-mounted components in Printed Circuit Board (PCB) fabrication, we propose a sample generation method using Stable Diffusion Model and ControlNet, as well as a defect detection method based on the Swin Transformer. The method consists of two stages: First, high-definition original images collected in industrial production and the corresponding prompts are input to Stable Diffusion Model and ControlNet for automatic generation of nonindependent samples. Subsequently, we integrate Swin Transformer as the backbone into the Cascade Mask R-CNN to improve the quality of defect features extracted from the samples for accurate detection box localization and segmentation. Instead of segmenting individual components on the PCB, the method inspects all components in the field of view simultaneously over a larger area. The experimental results demonstrate the effectiveness of our method in scaling up nonindependent sample datasets, thereby enabling the generation of high-quality datasets. The method accurately recognizes targets and detects defect types when performing multitarget inspection on printed circuit boards. The analysis against other models shows that our improved defect detection and segmentation method improves the Average Recall (AR) by 2.8% and the mean Average Precision (mAP) by 1.9%.

2.
Angew Chem Int Ed Engl ; 63(29): e202407034, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38708741

RESUMEN

Chirality, a fundamental principle in chemistry, biology, and medicine, is prevalent in nature and in organisms. Chiral molecules, such as DNA, RNA, and proteins, are crucial in biomolecular synthesis, as well as in the development of functional materials. Among these, 1,1'-binaphthyl-2,2'-diol (BINOL) stands out for its stable chiral configuration, versatile functionality, and commercial availability. BINOL is widely employed in asymmetric catalysis and chiral materials. This review mainly focuses on recent research over the past five years concerning the use of BINOL derivatives for constructing chiral macrocycles and cages. Their contributions to chiral luminescence, enantiomeric separation, transmembrane transport, and asymmetric catalysis were examined.

3.
J Am Chem Soc ; 146(19): 13226-13235, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38700957

RESUMEN

Strained carbon nanohoops exhibit attractive photophysical properties due to their unique π-conjugated structure. However, incorporation of such nanohoops into the pincer ligand of metal complexes has rarely been explored. Herein, a new family of highly strained cyclometalated platinum(II) nanohoops has been synthesized and characterized. Strain-promoted C-H bond activation has been observed during the metal coordination process, and Hückel-Möbius topology and random-columnar packing in the solid state are found. Transient absorption spectroscopy revealed the size-dependent excited state properties of the nanohoops. Moreover, the nanohoops have been successfully employed as active materials in the fabrication of solution-processable resistive memory devices, including the use of the smallest platinum(II) nanohoop for the fabrication of a binary memory, with low switching threshold voltages of ca. 1.5 V, high ON/OFF current ratios, and good stability. These results demonstrate that strain incorporation into the structure can be an effective strategy to fundamentally fine-tune the reactivity, optoelectronic, and resistive memory properties.

5.
J Am Chem Soc ; 146(8): 5186-5194, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38311922

RESUMEN

Isomer-pure functionalized fullerenes are required to boost the development of fullerene chemistry in any field, but their multiple functionalization renders a mixture of regioisomers that are very difficult to purify by chromatography. For the specific case of C70, its nonspherical geometry makes its regioselective functionalization more challenging than that of spherical C60. In this work, the supramolecular mask approach is applied for the first time to C70, which is encapsulated in two different nanocapsules to achieve the Bingel bis-cyclopropanation at α-bonds of opposite poles. Based on the tetragonal prismatic geometry imposed by the smaller supramolecular mask tested, the obtained major bis-adduct is completely reversed (major 5 o'clock) compared to bare C70 functionalization (major 2 o'clock). Moreover, by further restricting the accessibility of C70 using a three-shell Matryoshka mask and dibenzyl-bromomalonate, a single regiospecific 2 o'clock bis-isomer is obtained, owing to the perfect complementarity of the mask and the addend steric properties. The outcome of the reactions is fully explained at the molecular level by means of a thorough molecular dynamics (MD) study of the accessibility of the α-bonds to produce the different bis-adducts.

6.
Chem Soc Rev ; 53(1): 47-83, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-37853792

RESUMEN

Fullerene chemistry has come a long way since 1990, when the first bulk production of C60 was reported. In the past decade, progress in supramolecular chemistry has opened some remarkable and previously unexpected opportunities regarding the selective (multiple) functionalization of fullerenes and their (self)assembly into larger structures and frameworks. The purpose of this review article is to provide a comprehensive overview of these recent developments. We describe how macrocycles and cages that bind strongly to C60 can be used to block undesired addition patterns and thus allow the selective preparation of single-isomer addition products. We also discuss how the emergence of highly shape-persistent macrocycles has opened opportunities for the study of photoactive fullerene dyads and triads as well as the preparation of mechanically interlocked compounds. The preparation of two- or three-dimensional fullerene materials is another research area that has seen remarkable progress over the past few years. Due to the rapidly decreasing price of C60 and C70, we believe that these achievements will translate into all fields where fullerenes have traditionally (third-generation solar cells) and more recently been applied (catalysis, spintronics).

7.
MedComm (2020) ; 4(4): e336, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37502610

RESUMEN

The molecular mechanisms underlying uric acid (UA)-induced mitochondrial dysfunction and apoptosis have not yet been elucidated. Herein, we investigated underlying mechanisms of UA in the development of mitochondrial dysfunction and apoptosis. We analyzed blood samples of individuals with normal UA levels and patients with hyperuricemia. Results showed that patients with hyperuricemia had significantly elevated levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, which may indicate liver or mitochondrial damage in patients with hyperuricemia. Subsequently, lipidomic analysis of mouse liver tissue mitochondria and human liver L02 cell mitochondria was performed. Compared with control group levels, high UA increased mitochondrial phosphatidylserine (PS) and decreased mitochondrial phosphatidylethanolamine (PE) levels, whereas the expression of mitochondrial phosphatidylserine decarboxylase (PISD) that mediates PS and PE conversion was downregulated. High UA levels also inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation as well as mitochondrial respiration, while inducing apoptosis both in vivo and in vitro. Treatment with allopurinol, overexpression of PISD, and lyso-PE (LPE) administration significantly attenuated the three above-described effects in vitro. In conclusion, UA may induce mitochondrial dysfunction and apoptosis through mitochondrial PISD downregulation. This study provides a new perspective on liver damage caused by hyperuricemia.

8.
Angew Chem Int Ed Engl ; 62(24): e202302978, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-36988014

RESUMEN

Both pillar[n]arenes (P[n]As) and [n]cycloparaphenylenes ([n]CPPs) play an important role in supramolecular chemistry. Herein, we report the precise synthesis of two multifunctional bismacrocycles [n]CPP-P[5]A by integrating P[5]A into the [n]CPP backbone. The photoluminescence quantum yield (ΦF ) of the bismacrocycles was found to show a dramatic increase relative to the corresponding [n]CPPs. The chiral enantiomers (pR)/(pS)-[8]CPP-P[5]A were successfully isolated by chiral HPLC, and showed promising properties of circularly polarized luminescence (glum ≈0.02). In addition, [n]CPP-P[5]A bismacrocycles are capable of binding pyridinium salts and fullerene derivatives with high affinity and specificity within the two distinct cavities. Transient absorption studies showed that photo-induced electron transfer occurs in [10]CPP-P[5]A⊃C60 complex. Our results suggest that [n]CPP-P[5]A are potentially useful in CPL-active materials, multiple guest recognition and supramolecular polymer preparation.

9.
J Lipid Res ; 64(3): 100337, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36716821

RESUMEN

Liver function indicators are often impaired in patients with type 2 diabetes mellitus (T2DM), who present higher concentrations of aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase than individuals without diabetes. However, the mechanism of liver injury in patients with T2DM has not been clearly elucidated. In this study, we performed a lipidomics analysis on the liver of T2DM mice, and we found that phosphatidylethanolamine (PE) levels were low in T2DM, along with an increase in diglyceride, which may be due to a decrease in the levels of phosphoethanolamine cytidylyltransferase (Pcyt2), thus likely affecting the de novo synthesis of PE. The phosphatidylserine decarboxylase pathway did not change significantly in the T2DM model, although both pathways are critical sources of PE. Supplementation with CDP-ethanolamine (CDP-etn) to increase the production of PE from the CDP-etn pathway reversed high glucose and FFA (HG&FFA)-induced mitochondrial damage including increased apoptosis, decreased ATP synthesis, decreased mitochondrial membrane potential, and increased reactive oxygen species, whereas supplementation with lysophosphatidylethanolamine, which can increase PE production in the phosphatidylserine decarboxylase pathway, did not. Additionally, we found that overexpression of PCYT2 significantly ameliorated ATP synthesis and abnormal mitochondrial morphology induced by HG&FFA. Finally, the BAX/Bcl-2/caspase3 apoptosis pathway was activated in hepatocytes of the T2DM model, which could also be reversed by CDP-etn supplements and PCYT2 overexpression. In summary, in the liver of T2DM mice, Pcyt2 reduction may lead to a decrease in the levels of PE, whereas CDP-etn supplementation and PCYT2 overexpression ameliorate partial mitochondrial function and apoptosis in HG&FFA-stimulated L02 cells.


Asunto(s)
Diabetes Mellitus Tipo 2 , Fosfatidiletanolaminas , Ratones , Animales , Fosfatidiletanolaminas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , ARN Nucleotidiltransferasas/metabolismo , Etanolaminas/farmacología , Etanolaminas/metabolismo , Hepatocitos/metabolismo , Mitocondrias/metabolismo , Apoptosis , Adenosina Trifosfato/metabolismo
10.
Cancers (Basel) ; 15(2)2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36672337

RESUMEN

Lipidomic analyses have suggested that palmitic acid (PA) is linked to gastric cancer. However, its effects and action mechanisms remain unclear. Therefore, we evaluated the effects of PA on cell proliferation, invasion, and apoptosis in human gastric cancer, as well as the role of p-STAT3 in mediating its effects. The results of the MTT and colony formation assays revealed that PA blocked gastric cancer cell proliferation in a concentration-dependent manner. The EdU-DNA assay indicated that 50 µM of PA could block gastric cell proliferation by 30.6-80.0%. The Transwell assay also confirmed the concentration dependence of PA-induced inhibitory effect on cell invasion. The flow cytometry analysis indicated that PA treatment for 18 h could induce gastric cancer cell apoptosis. The immunohistochemical staining revealed that p-STAT3 levels were higher in the gastric cancer tissues than in the control tissues. We demonstrated that PA treatment for 12 h decreased the expressions of p-STAT3, p-JAK2, N-cadherin, and vimentin, and inhibited the nuclear expression of p-STAT3 in gastric cancer cells. Finally, PA treatment (50 mg/kg) decreased gastric cancer growth (54.3%) in the xenograft models. Collectively, these findings demonstrate that PA inhibits cell proliferation and invasion and induces human gastric cancer cell apoptosis.

11.
Chemistry ; 29(16): e202203734, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36507855

RESUMEN

We investigate the gas-phase chemistry of noncovalent complexes of [10]cycloparaphenylene ([10]CPP) with C60 and C70 by means of atmospheric pressure photoionization and electrospray ionization mass spectrometry. The literature-known [1 : 1] complexes, namely [10]CPP⊃C60 and [10]CPP⊃C70 , are observed as radical cations and anions. Their stability and charge distribution are studied using energy-resolved collision-induced dissociation (ER-CID). These measurements reveal that complexes with a C70 core exhibit a greater stability and, on the other hand, that the radical cations are more stable than the respective radical anions. Regarding the charge distribution, in anionic complexes charges are exclusively located on C60 or C70 , while the charges reside on [10]CPP in the case of cationic complexes. [2 : 1] complexes of the ([10]CPP2 ⊃C60/70 )+ ⋅/- ⋅ type are observed for the first time as isolated solitary gas-phase species. Here, C60 -based [2 : 1] complexes are less stable than the respective C70 analogues. By virtue of the high stability of cationic [1 : 1] complexes, [2 : 1] complexes show a strongly reduced stability of the radical cations. DFT analyses of the minimum geometries as well as molecular dynamics calculations support the experimental data. Furthermore, our novel gas-phase [2 : 1] complexes are also found in 1,2-dichlorobenzene. Insights into the thermodynamic parameters of the binding process as well as the species distribution are derived from isothermal titration calorimetry (ITC) measurements.

13.
Inorg Chem ; 61(49): 20008-20025, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36426422

RESUMEN

The synthesis and biological assessment of neutral or cationic platinum group metal-based anticancer complexes have been extremely studied, whereas there are few reports on the corresponding zwitterionic complexes. Herein, the synthesis, characterization, and bioactivity of zwitterionic half-sandwich phosphine-imine iridium(III), rhodium(III), and ruthenium(II) complexes were presented. The sulfonated phosphine-imine ligand and a group of zwitterionic half-sandwich P,N-chelating organometallic complexes were fully characterized by nuclear magnetic resonance (NMR), mass spectrum (electrospray ionization, ESI), elemental analysis, and X-ray crystallography. The solution stability of these complexes and their spectral properties were also determined. Notably, almost all of these complexes showed enhanced anticancer activity against model HeLa and A549 cancer cells than the corresponding zwitterionic pyridyl-imine N,N-chelating iridium(III) and ruthenium(II) complexes, which have exhibited inactive or low active in our previous work. The increase in the lipophilic property and intracellular uptake levels of these zwitterionic P,N-chelating complexes appeared to be associated with their superior cytotoxicity. In addition, these complexes showed biomolecular interactions with bovine serum albumin (BSA). The flow cytometry studies indicated that the representative complex Ir1 could induce early-stage apoptosis in A549 cells. Further, confocal microscopy imaging analysis displayed that Ir1 entered A549 cells through the energy-dependent pathway, targeted lysosome, and could cause lysosomal damage. In particular, these complexes could impede cell migration in A549 cells.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Rodio , Rutenio , Humanos , Iridio/farmacología , Iridio/química , Rutenio/farmacología , Rutenio/química , Rodio/farmacología , Rodio/química , Complejos de Coordinación/química , Antineoplásicos/química , Modelos Moleculares , Iminas/química , Línea Celular Tumoral
14.
Biochem Biophys Res Commun ; 617(Pt 2): 55-61, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35696777

RESUMEN

The molecular mechanisms of uric acid (UA)-induced liver injury has not been clearly elucidated. In this study, we aimed to investigate the effect and action mechanisms of UA in liver injury. We analyzed the damaging effect of UA on mouse liver and L02 cells and subsequently performed metabolomics studies on L02 cells to identify abnormal metabolic pathways. Finally, we verified transcription factors that regulate related metabolic enzymes. UA directly activated the hepatic NLRP3 inflammasome and Bax apoptosis pathway invivo and invitro. Related metabolites in the arginine biosynthesis pathway (or urea cycle), l-arginine and l-argininosuccinate were decreased, and ammonia was increased in UA-stimulated L02 cells, which was mediated by carbamoyl phosphate synthase 1 (CPS1), argininosuccinate synthase (ASS) and argininosuccinate lyase (ASL) downregulation. UA upregulated hypoxia inducible factor-1alpha (HIF-1α) invivo and invitro, and HIF-1α inhibition alleviated the UA-induced ASS downregulation and hepatocyte injury. In conclusion, UA upregulates HIF-1α and inhibits urea cycle enzymes (UCEs). This leads to liver injury, with evidence of hepatocyte inflammation, apoptosis and oxidative stress.


Asunto(s)
Hiperuricemia , Animales , Arginina/metabolismo , Argininosuccinato Sintasa , Hepatocitos/metabolismo , Humanos , Hiperuricemia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Hígado/metabolismo , Ratones , Urea/metabolismo
16.
Nat Chem ; 13(5): 420-427, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33859394

RESUMEN

Molecular Russian dolls (matryoshkas) have proven useful for testing the limits of preparative supramolecular chemistry but applications of these architectures to problems in other fields are elusive. Here we report a three-shell, matryoshka-like complex-in which C60 sits inside a cycloparaphenylene nanohoop, which in turn is encapsulated inside a self-assembled nanocapsule-that can be used to address a long-standing challenge in fullerene chemistry, namely the selective formation of a particular fullerene bis-adduct. Spectroscopic evidence indicates that the ternary complex is sufficiently stable in solution for the two outer shells to affect the addition chemistry of the fullerene guest. When the complex is subjected to Bingel cyclopropanation conditions, the exclusive formation of a single trans-3 fullerene bis-adduct was observed in a reaction that typically yields more than a dozen products. The selectivity facilitated by this matryoshka-like approach appears to be a general phenomenon and could be useful for applications where regioisomerically pure C60 bis-adducts have been shown to have superior properties compared with isomer mixtures.

17.
Oxid Med Cell Longev ; 2021: 1470380, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33854690

RESUMEN

Uric acid is the end product of purine metabolism in humans. Hyperuricemia is a metabolic disease caused by the increased formation or reduced excretion of serum uric acid (SUA). Alterations in SUA homeostasis have been linked to a number of diseases, and hyperuricemia is the major etiologic factor of gout and has been correlated with metabolic syndrome, cardiovascular disease, diabetes, hypertension, and renal disease. Oxidative stress is usually defined as an imbalance between free radicals and antioxidants in our body and is considered to be one of the main causes of cell damage and the development of disease. Studies have demonstrated that hyperuricemia is closely related to the generation of reactive oxygen species (ROS). In the human body, xanthine oxidoreductase (XOR) catalyzes the oxidative hydroxylation of hypoxanthine to xanthine to uric acid, with the accompanying production of ROS. Therefore, XOR is considered a drug target for the treatment of hyperuricemia and gout. In this review, we discuss the mechanisms of uric acid transport and the development of hyperuricemia, emphasizing the role of oxidative stress in the occurrence and development of hyperuricemia. We also summarize recent advances and new discoveries in XOR inhibitors.


Asunto(s)
Xantina Deshidrogenasa/antagonistas & inhibidores , Humanos , Hiperuricemia , Estrés Oxidativo
18.
Molecules ; 26(4)2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33670007

RESUMEN

A novel series of 4-(4-formamidophenylamino)-N-methylpicolinamide derivatives were synthesized and evaluated against different tumor cell lines. Experiments in vitro showed that these derivatives could inhibit the proliferation of two kinds of human cancer cell lines (HepG2, HCT116) at low micromolar concentrations and the most potent analog 5q possessed broad-spectrum antiproliferative activity. Experiments in vivo demonstrated that 5q could effectively prolong the longevity of colon carcinoma-burdened mice and slow down the progression of cancer cells by suppression of angiogenesis and the induction of apoptosis and necrosis.


Asunto(s)
Antineoplásicos/farmacología , Ácidos Picolínicos/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Ácidos Picolínicos/síntesis química , Ácidos Picolínicos/química , Células Tumorales Cultivadas
19.
J Mater Chem B ; 9(8): 1965-1979, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33595050

RESUMEN

Hollow iron oxide nanoparticles (NPs) are an attractive class of hollow nanostructures that have received significant attention in the biomedical field due to their low toxicity, good biocompatibility, and intrinsic magnetic nature. We review the recent advances in the preparation, surface functionalization, and biomedical applications of hollow iron oxide NPs. Hollow iron oxide NPs are generally synthesized by the following five strategies, including the Kirkendall effect, galvanic replacement, chemical etching, nano template-mediated, and hydrothermal/solvothermal routes. We also summarize the general strategies for iron oxide NP surface functionalization. Moreover, various promising biomedical applications of hollow iron oxide NPs, including magnetic resonance imaging, drug delivery, and cancer therapy, are highlighted in detail. Finally, perspectives of hollow iron oxide NPs are provided.


Asunto(s)
Materiales Biocompatibles/química , Compuestos Férricos/química , Nanopartículas , Animales , Materiales Biocompatibles/farmacología , Compuestos Férricos/farmacología , Humanos
20.
Orthop Surg ; 12(5): 1456-1463, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33073535

RESUMEN

OBJECTIVES: To compare the clinical outcomes of plate fixation and arthroscopic-assisted plate fixation in patients with displaced isolated medium-sized fractures of the greater tuberosity. METHODS: From July 2013 to October 2017, patients with displaced isolated medium-sized fractures of the greater tuberosity who underwent arthroscopic-assisted plate fixation (ASPF group) or open reduction and internal plate fixation (ORIF group) were retrospectively reviewed and analyzed. There were 19 patients in the ASPF group and 27 patients in the ORIF group, with comparable demographic characteristics. The average age of patients was 49.4 ± 12.1 years in the ASPF group and 46.9 ± 11.4 years in the ORIF group. The shoulder function reflected by the Constant-Murley (CS) scores, the American Shoulder and Elbow Surgeons (ASES) scores, and the range of motion (ROM) in the both groups at the last follow-up were analyzed in the study. Surgery time, postoperative pain, and postoperative complications were also reviewed. RESULTS: A total of 46 eligible patients were included in this study. The mean follow-up was similar for the ASPF (19.4 ± 3.7 months) and the ORIF (18.2 ± 3.2 months) groups (P = 0.372). All patients had achieved primary incision healing in both groups at the last follow-up. The surgery time was 96.8 ± 11.7 min and 64.2 ± 8.3 min in the ASPF group and the ORIF group, respectively (P < 0.01). All the CS scores (P = 0.278), ASES scores (P = 0.426), and ROM were slightly better in the ASPF group than in the ORIF group, but they did not attain significant differences. In addition, there was no significant difference in the postoperative complication rate between the ASPF group (10.5%) and the ORIF group (18.5%) (P = 0.522). In the ASPF group, there was only one patient with postoperative shoulder stiffness and one case of fracture malunion. In the ORIF group, there were two cases of postoperative shoulder stiffness, two cases of fracture malunoin, and one case of subacromial impingement. Other major postoperative complications, such as fracture nonunion, pullout of the suture anchor, and screw penetration, were not observed in either group. CONCLUSION: Arthroscopic-assisted plate fixation is effective and may be an alternative in the treatment of displaced isolated medium-sized fractures of the greater tuberosity.


Asunto(s)
Artroscopía/métodos , Placas Óseas , Fijación Interna de Fracturas/métodos , Fracturas del Húmero/cirugía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Estudios Retrospectivos
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