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1.
J Am Chem Soc ; 146(1): 609-616, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38153960

RESUMEN

Two unprecedented tetratriacontanuclear and tetraicosanuclear gold(I) sulfido clusters (denoted as Au34-LMe and Au24-LCbz) with different temperature-induced stimulus-responsive behavior and emission property have been constructed by taking advantage of the judiciously designed bidentate phosphine ligand. Au34-LMe represents the highest nuclearity of the gold(I) sulfido cluster with more than a thousand atoms in the molecule. Octagonal macrocycles based on metal-cluster nodes have been assembled for the first time. The self-assembly and temperature-induced stimulus-responsive processes were monitored by 1H and 31P{1H} NMR spectroscopy, and the identities of the discrete gold(I) complexes were established by single-crystal structural analysis and high-resolution electrospray ionization mass spectrometry data. The steric effects exerted by the substituents on the V-shaped 1,3-bis(diphenylphosphino)benzene ligand have been shown to govern the self-assembly from the 1D cluster and 3D cage to 2D macrocycles. This work not only offers a new strategy to construct and regulate the structure of 2D macrocyclic gold(I) sulfido complexes but also lays the foundation for the future precise design and controlled construction of higher polygonal and cluster-node macrocycles.

2.
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.

3.
J Am Chem Soc ; 145(13): 7454-7461, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36943768

RESUMEN

Stimuli-responsive structural transformation has attracted much attention for its potential to mimic the behavior of biological transformations and functions. Here, two unprecedented dodecanuclear and pentadecanuclear gold(I) sulfido clusters (denoted trans-Au12 and trans-Au15, respectively) with impressive stimuli-responsive interconversion have been obtained by taking advantage of the judiciously designed tridentate phosphine ligand Ltrans as the building block. Both UV light and temperature can be applied to trigger the structural conversions between trans-Au12 and trans-Au15. In addition, NMR, high-resolution electrospray ionization mass spectrometry, and UV-vis absorption spectroscopy have been employed to monitor the transformation process and decipher the mechanism of structural conversion. This work not only provides a paradigm to investigate photo-induced cluster-to-cluster transformation based on polydentate phosphine ligands but also offers a new direction for the construction of the stimuli-responsive materials.

4.
J Am Chem Soc ; 144(43): 19748-19757, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36264179

RESUMEN

Decanuclear and pentanuclear gold(I) sulfido complexes of phenanthrene- and dibenzothiophene-based diphosphine ligands were synthesized and characterized. Unprecedented stimuli-induced reversible transformation between decanuclear and pentanuclear gold(I) sulfido complexes was observed, which could be readily monitored by NMR and UV-vis absorption spectroscopy in solution. Remarkably, the decanuclear gold(I) sulfido complex (Au10-LPh) was found to show a highly reversible transformation process, which is stable for over 10 successive cycles in solution. The stimuli-induced reversible transformation behavior of the gold(I) sulfido complexes was found to depend on the P-P bite distance of the bidentate phosphine ligands.

5.
Heart Surg Forum ; 25(5): E715-E717, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36317915

RESUMEN

We describe a one-stop procedure for aortopulmonary collateral artery (APCA) and postoperative complications of Tetralogy of Fallot (TOF). Postoperative complications of TOF include right ventricular outflow tract stenosis, pulmonary valvular annular stenosis, pulmonary regurgitation, and aortopulmonary artery stenosis. The one-stop procedure was defined as after APCA embolization. The heart continued to function under cardiopulmonary bypass during median sternotomy to reconstruct the right ventricular outflow tract with a valved conduit and replace the aortopulmonary artery. A biological valved was sewed within the valved conduit in an artificial blood vessel in vitro and subsequently was used in the procedure and achieved significant results.


Asunto(s)
Tetralogía de Fallot , Humanos , Tetralogía de Fallot/cirugía , Constricción Patológica , Arteria Pulmonar/cirugía , Ventrículos Cardíacos , Complicaciones Posoperatorias/cirugía
6.
J Am Chem Soc ; 143(45): 19008-19017, 2021 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-34732047

RESUMEN

Self-assembly of three-dimensional (3D) metallosupramolecular cages has drawn increasing attention for their potential to interconvert between different architectures due to the dynamic and reversible features of the coordination bond. These supramolecular transformations can provide unique approaches for the construction of stimuli-responsive supramolecular model systems to mimic biological transformation processes. While gold(I) clusters have attracted much interest due to their propensity to exhibit aurophilic interactions, the construction of 3D gold(I) cluster cages has remained a challenging and daunting task. Here, we proposed a "de-aurophilic" interaction strategy, which involves the prevention of aurophilic interaction formation between the basic [(µ3-S)Au3]+ units, to construct 3D gold(I) cluster cages. Through the judicious design of diphosphine ligands, an unprecedented class of gold(I) cluster cages with adaptive structures has been constructed. These gold(I) cluster cages are found to show intriguing stimuli-responsive structure transformation and interconversion. This work not only provides a strategy for the design and construction of novel 3D supramolecular cages based on cluster nodes but also offers a paradigm to study the stimuli-responsive structural interconversion between the unique structures of these gold(I) cluster cages.

7.
BMC Gastroenterol ; 21(1): 182, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33879085

RESUMEN

BACKGROUND: Transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) are effective treatment methods for unresectable hepatocellular carcinoma (HCC). However, there is still a lack of clinical research on whether early sequential RFA, compared with late combination therapy, can improve the long-term efficacy of initial TACE treatment. METHODS: This retrospective study investigated a cohort of patients who underwent combination therapy using TACE and RFA (TACE followed by RFA) from January 2010 to January 2020 at our medical centre. A total of 96 patients underwent TACE combined with early RFA (usually during the first hospitalization), which was called TACE + eRFA. Thirty-four patients received 1-2 palliative TACE treatments first and then underwent TACE treatment combined with late RFA (TACE + lRFA). All patients continued to receive palliative TACE treatments after intrahepatic lesion progression until reaching intolerance. The overall survival (OS) rate, time to tumour progression (TTP), tumour response rate and major complication rates were compared between the two groups. RESULTS: There were significant differences in the median OS (46 months vs 33 months; P = 0.013), median TTP (28 months vs 14 months; P < 0.00), objective response rate (ORR) (89.6% vs 61.8%, P = 0.000) and disease control rate (DCR) (94.8% vs 73.5% P = 0.002) between the two groups. Multivariable analysis revealed that the Barcelona Clinic Liver Cancer stage was an independent risk factor for OS. Meanwhile, multivariable analysis revealed that TACE + eRFA was associated with an enhanced TTP. CONCLUSION: Early sequential RFA treatment in patients with early-intermediate HCC can improve local tumour control and clinical outcomes while reducing the frequency of TACE treatment. In clinical practice, in HCC patients initially treated with TACE, it is recommended to combine RFA as soon as possible to obtain long-term survival.


Asunto(s)
Carcinoma Hepatocelular , Ablación por Catéter , Quimioembolización Terapéutica , Neoplasias Hepáticas , Ablación por Radiofrecuencia , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/efectos adversos , Terapia Combinada , Humanos , Neoplasias Hepáticas/terapia , Ablación por Radiofrecuencia/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento
8.
J Am Chem Soc ; 142(26): 11560-11568, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32567307

RESUMEN

A series of polynuclear gold(I) sulfido complexes of bis(diphenylphosphino)amine ligands has been synthesized and characterized. A rather small variation in the conformation of the bis(diphenylphosphino)amine ligands has led to distinct differences in the identity of the polynuclear gold(I) sulfido complexes formed. Unprecedented concentration-dependent and solvation-dependent reversible cluster-to-cluster transformation between a dodecanuclear gold(I) sulfido complex (LMe-Au12) and a hexanuclear gold(I) sulfido complex (LMe-Au6) has been observed. The transformation process has been monitored not only by 1H and 31P{1H} NMR spectroscopy but also by UV-vis absorption spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) in the solution state. This work has provided a simple approach to achieve structure modulation of gold(I) sulfido complexes and an understanding of supramolecular transformations via external stimuli.

9.
BMC Cancer ; 20(1): 854, 2020 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-32891131

RESUMEN

BACKGROUND: To evaluate the impact of age on the efficacy of neoadjuvant chemoradiotherapy (NCRT) in patients with locally advanced rectal cancer (LARC). METHOD: LARC patients undergoing NCRT and radical surgery from 2011 to 2018 were divided into young (< 40 years) and old (≥40 years) groups. Multivariate analyses were performed to identify predictive factors for pathological complete response (pCR). Predictive nomograms and decision curve analysis were used to compare the models including/excluding age groups. Immunohistochemical analysis was performed to detect CD133 expression in LARC patients. RESULT: A total of 901 LARC patients were analyzed. The young group was associated with poorly differentiated tumors, more metastatic lymph nodes, higher perineural invasion, and a lower tumor regression grade (P = 0.008; P < 0.001; P < 0.001; P = 0.003). Logistic regression analysis demonstrated that age < 40 years (HR = 2.190, P = 0.044), tumor size (HR = 0.538, P < 0.001), pre-NCRT cN stage (HR = 0.570, P = 0.036), and post-NCRT CEA level (HR = 0.877, P = 0.001) were significantly associated with pCR. Predictive nomograms and decision curve analysis demonstrated that the predictive ability of models including the age group was superior to that of models excluding the age group. Higher CD133 expression was more common in young LARC patients. CONCLUSION: Young patients with LARC were associated with lower pCR rates following NCRT. The ability of the predictive model was greater when based on the age group. Young LARC patients were associated with a higher CD133+ tumor stem cell burden, which contributed to the lower pCR rates.


Asunto(s)
Adenocarcinoma/terapia , Quimioradioterapia/métodos , Terapia Neoadyuvante/métodos , Neoplasias del Recto/terapia , Antígeno AC133/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/cirugía , Adulto , Factores de Edad , Anciano , Terapia Combinada/métodos , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Nomogramas , Pronóstico , Estudios Prospectivos , Neoplasias del Recto/metabolismo , Neoplasias del Recto/cirugía , Estudios Retrospectivos
10.
Anticancer Drugs ; 31(9): 966-972, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31977568

RESUMEN

To evaluate the predictive value of preoperative biochemical marker [platelet-to-lymphocyte ratio (PLR)] in patients with advanced hepatocellular cancer receiving transarterial chemoembolization (TACE) plus targeted molecular therapy (apatinib) treatment. Clinical records of 134 patients receiving the treatment of TACE + apatinib (TACE-A) and the treatment of TACE alone were compared in a single-center study. Time to progression (TTP) and overall survival (OS) were compared between TACE-A and TACE alone groups in patients with PLR > 150 and PLR ≤ 150, respectively. The area under the receiver operating characteristic (ROC) curve was used to determine the prediction power of PLR. The median TTP and OS in the TACE-A group were significantly longer than those in the TACE alone group (P < 0.001). The median TTP and OS in the TACE-A (PLR ≤ 150) group were longer than those in the TACE-A (PLR > 150) group (P < 0.05). There was no significant difference between TACE-A (PLR > 150) and TACE alone (P = 0.232) groups in OS, but the median TTP in the TACE-A (PLR > 150) group was longer than that in the TACE alone group (P = 0.001). ROC analysis showed that the area under the curve was 0.643 and 0.623 for 6- and 12-month survival, respectively. PLR might predict the results of patients with advanced hepatocellular carcinoma received TACE-A treatment.


Asunto(s)
Plaquetas/patología , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/terapia , Linfocitos/patología , Piridinas/administración & dosificación , Administración Oral , Antineoplásicos/administración & dosificación , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos
11.
BMC Gastroenterol ; 20(1): 205, 2020 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-32600349

RESUMEN

BACKGROUND: Transarterial chemoembolization (TACE), radiofrequency ablation (RFA), and iodine 125 seeds implantation are optional treatments for hepatocellular carcinoma (HCC). The aim of this study is to compare the efficacy of the combined treatment of TACE with iodine 125 seeds implantation (TACE-iodine 125) with TACE with RFA (TACE-RFA) in patients with early- and intermediate-stage HCC. METHODS: The study included 112 patients who were diagnosed with early- and intermediate-stage HCC from January 1, 2014, to May 31, 2018. Among them, 38 patients were treated with TACE-Iodine 125, and 74 with TACE-RFA. The efficacy of the two treatment groups was retrospectively analyzed. To reduced the selective bias, a propensity score matching (PSM) analysis and inverse probability of treatment weighting (IPTW) method were used to compare the outcomes between the two groups. RESULTS: In the absence of PSM and IPTW, the median overall survival (OS) and progression-free survival (PFS) of the TACE-RFA group were slightly longer than those of the TACE-Iodine 125 group (OS: 41 months vs. 36 months; PFS: 18 months vs. 15 months). However, there were no statistically significant differences in the median OS, PFS, and objective response rate (ORR) between the two groups (P > 0.05). After adjusting the age, gender, Child-Pugh class, Barcelona Clinic Liver Cancer (BCLC) stage, and Alpha-fetoprotein (AFP), TACE-Iodine 125 treatment was not associated with a significant increasing the risks of death (HR: 0.763; 95%CI: 0.403,1.345, P = 0.320) and recurrence (HR: 1.020; 95%CI: 0.645,1.611, P = 0.934). After PSM, 35 matched pairs of patients were obtained, and there were no statistically significant differences in the median OS and PFS between the two groups. After IPTW, similar results presented. CONCLUSIONS: The combination of TACE with iodine 125 seeds implantation may represent an effective treatment for patients with early- and intermediate-stage HCC.


Asunto(s)
Carcinoma Hepatocelular , Ablación por Catéter , Quimioembolización Terapéutica , Neoplasias Hepáticas , Ablación por Radiofrecuencia , Carcinoma Hepatocelular/terapia , Terapia Combinada , Humanos , Radioisótopos de Yodo , Neoplasias Hepáticas/terapia , Recurrencia Local de Neoplasia , Ablación por Radiofrecuencia/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento
12.
J Card Surg ; 35(11): 3078-3087, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33032378

RESUMEN

BACKGROUND: We developed an integrated triple-branched stent to treat acute DeBakey type I aortic dissection (AD) and modified it to enhance its adaptability. However, whether the patients treated by the modified stent would achieve better long-term prognosis is unknown. METHODS: This study enrolled 147 patients with acute DeBakey type I AD. The original integrated triple-branched stents were used in 57 patients (Group A) between July 2012 and August 2013, and the modified stents in 90 patients (Group B) between September 2013 and March 2015. Clinical characteristics, surgical data, postoperative complications, mortality, and follow-up data of the two groups were analyzed. RESULTS: The two groups presented comparable early death rates (Group A = 7.0%, Group B = 5.9%; p = .719). The incidence of postoperative acute kidney injury (AKI) was lower in Group B (10.0%) versus Group A (24.6%) (p = .018). Compared with the original integrated triple-branched stent graft, the modified stent could reduce the risk of early postoperative AKI (OR [95% CI] = 0.36 [0.14, 0.94]). Early endoleak rates were significantly lower in Group B (1.0%) compared to Group A (9.4%) (p = .004). During follow-up, there were five deaths in Group A (9.4%) and six deaths in Group B (7.2%) (p = .646). Chronic kidney injury (7.5% vs. 3.6%; p = .311), delayed endoleak (11.3% vs. 4.8%; p = .157), and late reinterventions (7.5% vs. 2.4%; p = .155) in the two groups were similar. CONCLUSIONS: In patients with acute DeBakey type I AD, the modified stent showed feasible and safe treatment outcomes and reduced early endoleak rates. However, the long-term effects were similar to the original treatment.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Disección Aórtica/cirugía , Procedimientos Endovasculares/métodos , Stents , Enfermedad Aguda , Adulto , Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
13.
Antonie Van Leeuwenhoek ; 111(2): 227-235, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28913769

RESUMEN

A Gram-positive, non-motile actinomycete, designated strain NEAU-FJL1T, was isolated from tomato root (Solanum lycopersicum L.) collected from Harbin, Heilongjiang province, north China. The strain formed single spores with smooth surfaces from substrate mycelia. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-FJL1T should be affiliated with the genus Plantactinospora and forms a distinct branch with its close neighbour Plantactinospora soyae NEAU-gxj3T (99.2% sequence similarity). The cell wall was found to contain meso-diaminopimelic acid and the whole cell sugars were identified as xylose, glucose, arabinose and galactose. The predominant menaquinones were identified as MK-10(H6) and MK-10(H4). The phospholipid profile was found to consist of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were identified as C15:0, iso-C16:0, anteiso-C17:0, C17:0 and iso-C15:0. With reference to phenotypic characteristics, phylogenetic data and DNA-DNA hybridization results, strain NEAU-FJL1T can be distinguished from its most closely related strain and classified as a new species, for which the name Plantactinospora solaniradicis sp. nov. is proposed. The type strain is NEAU-FJL1T (= DSM 100596T = CGMCC 4.7284T).


Asunto(s)
Micromonosporaceae/clasificación , Raíces de Plantas/microbiología , Solanum lycopersicum/microbiología , Composición de Base , Girasa de ADN/genética , Genoma Fúngico/genética , Genómica/métodos , Micromonosporaceae/citología , Micromonosporaceae/genética , Filogenia , ARN Ribosómico 16S/genética
14.
J Am Chem Soc ; 139(24): 8237-8244, 2017 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-28558197

RESUMEN

Lanthanide-containing molecules have many potential applications in material science and biology, that is, luminescent sensing/labling, MRI, magnetic refrigeration, and catalysis among others. Coordination-directed self-assembly has shown great power in the designed construction of well-defined supramolecular systems. However, application of this strategy to the lanthanide edifices is challenging due to the complicated and greatly labile coordination numbers and geometries for lanthanides. Here we demonstrate a sensitive structural switching phenomenon during the stereocontrolled self-assembly of a group of Ln2nL3n (Ln for lanthanides, L for organic ligands, and n = 1, 2, 4) compounds. Systematic variation of the offset distances between the two chelating arms on the bis(tridentate) ligands dictated the final outcomes of the lanthanide assembly, ranging from Ln2L3 helicates and Ln4L6 tetrahedra to Ln8L12 cubes. Remarkably, the borderline case leading to the formation of a mixture of the helicate and the tetrahedron was clearly revealed. Moreover, the concentration-dependent self-assembly of an unprecedented cubic Ln8L12 complex was also confirmed. The luminescent lanthanide cubes can serve as excellent turn-off sensors in explosives detection, featuring high selectivity and sensitivity toward picric acid. All complexes were confirmed by NMR, ESI-TOF-MS, and single crystal X-ray diffraction studies. Our results provide valuable design principles for the coordination self-assembly of multinuclear functional lanthanide architectures.

15.
J Am Chem Soc ; 137(26): 8550-5, 2015 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-26065490

RESUMEN

Coordination-directed self-assembly has become a well-established technique for the construction of functional supramolecular structures. In contrast to the most often exploited transition metals, trivalent lanthanides Ln(III) have been less utilized in the design of polynuclear self-assembled structures despite the wealth of stimulating applications of these elements. In particular, stereochemical control in the assembly of lanthanide chiral cage compounds is not easy to achieve in view of the usually large lability of the Ln(III) ions. We report here the first examples of stereoselective self-assembly of chiral luminescent europium coordination tetrahedral cages and their intriguing self-sorting behavior. Two pairs of R and S ligands are designed on the basis of the pyridine-2,6-dicarboxamide coordination unit, bis(tridentate) L1 and tris(tridentate) L2. Corresponding chiral Eu4(L1)6 and Eu4(L2)4 topological tetrahedral cages are independently assembled via edge- and face-capping design strategies, respectively. The chirality of the ligand is transferred during the self-assembly process to give either Δ or Λ metal stereochemistry. The self-assembled cages are characterized by NMR, high-resolution ESI-TOF-MS, and in one case by X-ray crystallography. Strict control of stereoselectivity is confirmed by CD spectroscopy and NMR enantiomeric differentiation experiments. Narcissistic self-sorting is observed in the self-assembly process when two differently shaped ligands L1 and L2 are mixed. More impressively, distinct self-sorting behavior between Eu4(L1)6 and Eu4(L2)4 coordination cages is observed for the first time when racemic mixtures of ligands are used. We envisage that chiral luminescent lanthanide tetrahedral cages could be used in chiroptical probes\sensors and enantioselective catalysis.

16.
ACS Omega ; 9(2): 2696-2706, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38250366

RESUMEN

The development and utilization of geothermal resources are effective ways to alleviate the current haze situation, adjust the energy structure, and achieve energy conservation and emission reduction. Geothermal formations typically contain extensive fracture networks, with fracture openings. These fracture networks can result in substantial losses of the drilling fluid and increased costs for geothermal drilling. Temporary plugging cements are used to solve the problem of lost circulation due to their high strength and high acid solubility. In this paper, two types of temporary plugging materials, magnesium oxysulfate (MOS) cement and magnesium oxychloride (MOC) cement, were prepared. The influence of the plugging agent on the flow field and the force exerted on the solid under the action of the fluid was analyzed using fluid-solid coupling software. The simulation results show that when subjected to a flow rate of 10 m/s, the edge of the cement experiences a significant force, while the stress is not widely transmitted to the middle and rear of the cement. This indicates that the cement has a strong resistance to the fluid flow. The fundamental characteristics of MOC cement and MOS cement, such as compressive strength and setting time, were investigated. The test results show that adjusting the molar ratio of the two types of cements can shorten the setting time by 60% and increase the compressive strength to up to 23 MPa. In addition, the acid solubility of the cement with different ratios of raw materials is above 95%. The plugging performance of these two cements as loss circulation materials was evaluated by using a physical simulation device. The pressure bearing capacity of the MOC cement with different MgO/MgCl2·6H2O/H2O molar ratios ranged between 13.4 and 23.6 MPa. The maximum bearing capacity of the MOS cement can reach up to 18.6 MPa. The results showed that both cements possess excellent plugging and pressure bearing capacity.

17.
Curr Mol Med ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38726777

RESUMEN

BACKGROUND: Osteoarthritis (OA) is a chronic joint disease characterized by the degradation of articular cartilage. Polyphyllin I (PPI) has anti-inflammatory effects in many diseases. However, the mechanism of PPI in OA remains unclear.

Methods: HC-a cells treated with IL-1ß were identified by immunofluorescence staining and microscopic observation. The expression of collagen II and DAPI in HC-a cells was detected by immunofluorescence. The effects of gradient concentration of PPI on IL-1ß-induced cell viability, apoptosis, senescence, and inflammatory factor release were detected by MTT, flow cytometry, SA-ß-Gal assay and ELISA, respectively. Expressions of apoptosis-related genes, extracellular matrix (ECM)- related genes, and TWIST1 were determined by qRT-PCR and western blot as needed. The above-mentioned experiments were conducted again after TWIST1 overexpression in IL-1ß-induced chondrocytes.

Results: IL-1ß reduced the number of chondrocytes and the density of collagen II. PPI (0.25, 0.5, 1 µmol/L) had no effect on cell viability, but it dose-dependently elevated the inhibition of cell viability regulated by IL-1ß. The elevation of cell apoptosis, senescence and expression of IL-6 and TNF-α were suppressed by PPI in a dosedependent manner. Additionally, PPI reduced the expression of cleaved caspase-3, bax, MMP-3, and MMP-13 and promoted the expression of collagen II. TWIST1 expression was diminished by PPI. TWIST1 overexpression reversed the abovementioned effects of PPI on chondrocytes.

Conclusion: PPI suppressed apoptosis, senescence, inflammation, and ECM degradation of OA chondrocytes by downregulating the expression of TWIST1.

18.
Sci Rep ; 14(1): 2045, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267449

RESUMEN

To investigate the prognostic value of lymph node status in patients with cervical cancer (CC) patients who underwent neoadjuvant chemotherapy (NACT) and followed hysterectomy. Patients in two referral centers were retrospectively analyzed. The baseline tumor size and radiological lymph node status (LNr) were evaluated on pre-NACT MRI. Tumor histology, differentiation and pathological lymph node status (LNp) were obtained from post-operative specimen. The log-rank test was used to compare survival between patient groups. Cox proportional hazards regression models were employed to estimate the hazard ratio (HR) of various factors with progression-free survival (PFS) and overall survival (OS). A total of 266 patients were included. Patients with 2018 FIGO IIIC showed worse PFS compared to those with FIGO IB-IIB (p < 0.001). The response rate in patients with LNp(-) was 64.1% (134/209), significantly higher than that of 45.6% (26/57) in patients with LNp( +) (p = 0.011). Multivariate Cox analysis identified the main independent predictors of PFS as LNp( +) (HR = 3.777; 95% CI 1.715-8.319), non-SCC (HR = 2.956; 95% CI 1.297-6.736), poor differentiation (HR = 2.370; 95% CI 1.130-4.970) and adjuvant radiation (HR = 3.266; 95% CI 1.183-9.019). The interaction between LNr and LNp regarding PFS were significant both for univariate and multivariate (P = 0.000171 and 1.5357e-7 respectively). In patients with LNr( +), a significant difference in PFS was observed between patients with LNp(-) and LNp( +) (p = 0.0027). CC patients with FIGO 2018 stage IIIC who underwent NACT and followed hysterectomy had worse PFS compared to those with IB-IIB. LNp( +), non-SCC, poor differentiation and adjuvant radiation were independent risk factors for PFS. The adverse prognostic value of LNp( +) was more significant in patients with LNr( +).


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/tratamiento farmacológico , Pronóstico , Terapia Neoadyuvante , Estudios Retrospectivos , Histerectomía , Ganglios Linfáticos/diagnóstico por imagen
19.
Nat Commun ; 15(1): 4688, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824144

RESUMEN

Ultrasmall copper nanoclusters have recently emerged as promising photocatalysts for organic synthesis, owing to their exceptional light absorption ability and large surface areas for efficient interactions with substrates. Despite significant advances in cluster-based visible-light photocatalysis, the types of organic transformations that copper nanoclusters can catalyze remain limited to date. Herein, we report a structurally well-defined anionic Cu40 nanocluster that emits in the second near-infrared region (NIR-II, 1000-1700 nm) after photoexcitation and can conduct single-electron transfer with fluoroalkyl iodides without the need for external ligand activation. This photoredox-active copper nanocluster efficiently catalyzes the three-component radical couplings of alkenes, fluoroalkyl iodides, and trimethylsilyl cyanide under blue-LED irradiation at room temperature. A variety of fluorine-containing electrophiles and a cyanide nucleophile can be added onto an array of alkenes, including styrenes and aliphatic olefins. Our current work demonstrates the viability of using readily accessible metal nanoclusters to establish photocatalytic systems with a high degree of practicality and reaction complexity.

20.
Abdom Radiol (NY) ; 48(7): 2207-2218, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37085731

RESUMEN

PURPOSE: To investigate the potential of intravoxel incoherent motion diffusion-weighted imaging (IVIM) for preoperative prediction of lymphovascular invasion (LVI) in gastric cancer (GC). METHODS: This study prospectively enrolled 90 patients (62 males, 28 females, 60.79 ± 9.99 years old) who received radical gastrostomy. Abdominal MRI examinations including IVIM were performed within 1 week before surgery. Patients were divided into LVI-positive and -negative group according to pathological diagnosis after surgery. The apparent diffusion coefficient (ADC) and IVIM parameters, including true diffusion coefficient (D), pseudodiffusion coefficient (D*), and pseudodiffusion fraction (f), were compared between the two groups. The relationship between MRI parameters and LVI was studied by Spearman's correlation analysis. Multivariable logistic regression analysis was used to screen independent predictors of LVI. Receiver-operating characteristic curve analyses were applied to evaluate the efficacy. RESULTS: The ADC, D in LVI-positive group were lower, whereas tumor thickness and f parameter in LVI-positive group were higher than those in LVI-negative group, and they were statistically correlated with LVI (p < 0.05). D, f and tumor thickness were independent risk factors of LVI. The area under the curve of ADC, D, f, thickness, and the combined parameter (D + f + thickness) were 0.667, 0.754, 0.695, 0.792, and 0.876, respectively. The combined parameter demonstrated higher efficacy than any other parameters (p < 0.05). CONCLUSION: The ADC, D, and f can effectively distinguish LVI status of GC. The D, f and thickness were independent predictors. The combination of the three predictors further improved the efficacy.


Asunto(s)
Neoplasias Gástricas , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Estudios Prospectivos , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/cirugía , Imagen de Difusión por Resonancia Magnética/métodos , Imagen por Resonancia Magnética , Movimiento (Física)
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