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1.
Cancer Cell Int ; 24(1): 71, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347631

RESUMO

OBJECTIVE: Gastric cancer (GC) stands as a prevalent and deadly global malignancy. Despite its role as a preoperative neoadjuvant therapy, Apatinib's effectiveness is curtailed among GC patients exhibiting elevated YY1 expression. YY1's connection to adverse prognosis, drug resistance, and GC metastasis is established, yet the precise underlying mechanisms remain elusive. This study aims to unravel potential pathogenic pathways attributed to YY1. DESIGN: Utilizing bioinformatics analysis, we conducted differentially expressed genes, functional annotation, and pathway enrichment analyses, and further validation through cellular and animal experiments. RESULTS: Higher YY1 expression correlated with diminished postoperative progression-free survival (PFS) and disease-specific survival (DSS) rates in TCGA analysis, identifying YY1 as an independent DSS indicator in gastric cancer (GC) patients. Notably, YY1 exhibited significantly elevated expression in tumor tissues compared to adjacent normal tissues. Bioinformatics analysis revealed noteworthy differentially expressed genes (DEGs), transcriptional targets, factors, and co-expressed genes associated with YY1. LASSO Cox analysis unveiled Transferrin as a prospective pivotal protein regulated by YY1, with heightened expression linked to adverse DSS and PFS outcomes. YY1's role in governing the p53 signaling pathway and ferroptosis in GC cells was further elucidated. Moreover, YY1 overexpression dampened immune cell infiltration within GC tumors. Additionally, YY1 overexpression hindered GC cell ferroptosis and mediated Apatinib resistance via the p53 pathway. Remarkably, IFN-a demonstrated efficacy in reversing Apatinib resistance and immune suppression in GC tissues. CONCLUSIONS: Our findings underscore the pivotal role of YY1 in driving GC progression and influencing prognosis, thus pinpointing it as a promising therapeutic target to enhance patient outcomes.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38561861

RESUMO

BACKGROUND AND AIM: Endoscopic resection has been successfully used for the removal of digestive submucosal tumors (SMTs). However, the cardia has been considered a challenging location for endoscopic resection due to its narrow lumen and sharp angle. The objective of this study was to establish a clinical scoring model to grade the technical difficulty of endoscopic resection for cardial SMTs. METHODS: A total of 246 patients who suffered cardial SMTs and received endoscopic resection were included in this retrospective study. All of them were randomized into the training cohort (n = 123) or internal validation cohort (n = 123). Potential predictors were analyzed using univariate analysis. Then, covariates with P < 0.05 were selected for the multivariate logistic regression model. The ß coefficients from the logistic regression model were used to create a scoring system for technical difficulty prediction by rounding the score to the nearest integer of the absolute ß coefficient value. RESULTS: The clinical score consisted of the following factors: male gender (2 points), extraluminal growth (3 points), and maximum diameter ≥3 cm (3 points). The scoring model demonstrated good discriminatory power, with an area under the receiver operating characteristic curve of 0.860 and a 95% confidence interval of 0.763-0.958. The model also showed a good goodness of fit in the Hosmer-Lemeshow test (P = 0.979). In the training cohort, the probability of encountering technical difficulty in the easy (score = 0), intermediate (score = 1-3), difficult (score = 4-6), and very difficult (score >6) categories was 0, 6.8%, 33.3%, and 100.0%, respectively; similarly, in the validation cohort, it was 0, 5.6%, 22.2%, and 50.0%, respectively. CONCLUSIONS: This scoring system could serve as a valuable tool for clinicians in predicting the technical difficulty of endoscopic resection for cardial SMTs.

3.
Pain Pract ; 24(1): 82-90, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37615236

RESUMO

PURPOSE: Accurate predictions of postoperative pain intensity are necessary for customizing analgesia plans. Insomnia is a risk factor for severe postoperative pain. Moreover, heart rate variability (HRV) can provide information on the sympathetic-parasympathetic balance in response to noxious stimuli. We developed a prediction model that uses the insomnia severity index (ISI), HRV, and other demographic factors to predict the odds of higher postoperative pain. METHODS: We recruited gynecological surgery patients classified as American Society of Anesthesiologists class 1-3. An ISI questionnaire was completed 1 day before surgery. HRV was calculated offline using intraoperative electrocardiogram data. Pain severity at the postanesthesia care unit (PACU) was assessed with the 0-10 numerical rating scale (NRS). The primary outcome was the model's predictive ability for moderate-to-severe postoperative pain. The secondary outcome was the relationship between individual risk factors and opioid consumption in the PACU. RESULTS: Our study enrolled 169 women. Higher ISI scores (p = 0.001), higher parasympathetic activity (rMSSD, pNN50, HF; p < 0.001, p < 0.001, p < 0.001), loss of fractal dynamics (SD2, alpha 1; p = 0.012, p = 0.039) in HRV analysis before the end of surgery were associated with higher NRS scores, while laparoscopic surgery (p = 0.031) was associated with lower NRS scores. We constructed a multiple logistic model (area under the curve = 0.852) to predict higher NRS scores at PACU arrival. The five selected predictors were age (OR: 0.94; p = 0.020), ISI score (OR: 1.14; p = 0.002), surgery type (laparoscopic or open; OR: 0.12; p < 0.001), total power (OR: 2.02; p < 0.001), and alpha 1 (OR: 0.03; p < 0.001). CONCLUSION: We employed a multiple logistic regression model to determine the likelihood of moderate-to-severe postoperative pain upon arrival at the PACU. Physicians could personalize analgesic regimens based on a deeper comprehension of the factors that contribute to postoperative pain.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Qualidade do Sono , Humanos , Feminino , Frequência Cardíaca/fisiologia , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Analgésicos , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/tratamento farmacológico
4.
Plant Cell Environ ; 46(9): 2747-2762, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37427808

RESUMO

Tropical forests are experiencing increases in vapour pressure deficit (D), with possible negative impacts on tree growth. Tree-growth reduction due to rising D is commonly attributed to carbon limitation, thus overlooking the potentially important mechanism of D-induced impairment of wood formation due to an increase in turgor limitation. Here we calibrate a mechanistic tree-growth model to simulate turgor limitation of radial stem growth in mature Toona cilitata trees in an Asian tropical forest. Hourly sap flow and dendrometer measurements were collected to simulate turgor-driven growth during the growing season. Simulated seasonal patterns of radial stem growth matched well with growth observations. Growth mainly occurred at night and its pre-dawn build-up appeared to be limited under higher D. Across seasons, the night-time turgor pressure required for growth was negatively related to previous midday D, possibly due to a relatively high canopy conductance at high D, relative to stem rehydration. These findings provide the first evidence that tropical trees grow at night and that turgor pressure limits tree growth. We suggest including turgor limitation of tree stem growth in models also for tropical forest carbon dynamics, in particular, if these models simulate effects of warming and increased frequency of droughts.


Assuntos
Floresta Úmida , Árvores , Pressão de Vapor , Água , Florestas , Carbono , Clima Tropical
5.
Gastrointest Endosc ; 98(4): 534-542.e7, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37207844

RESUMO

BACKGROUND AND AIMS: Stenosis after esophageal endoscopic submucosal dissection (ESD) has a high incidence, and muscular injury is an important risk factor for esophageal stenosis. Hence, this study aimed to classify muscular injury degrees and investigate their association with postoperative stenosis. METHODS: This retrospective study included 1033 patients with esophageal mucosal lesions treated with ESD between August 2015 and March 2021. Demographic and clinical parameters were analyzed, and stenosis risk factors were identified using multivariate logistic regression. A novel muscular injury classification system was proposed and used to investigate the association between different muscular injury degrees and postoperative stenosis. Finally, a scoring system was established to predict muscular injury. RESULTS: Of 1033 patients, 118 (11.4%) had esophageal stenosis. The multivariate analysis demonstrated that the history of endoscopic esophageal treatment, circumferential range, and muscular injury were significant risk factors for esophageal stenosis. Patients with type II muscular injuries tended to develop complex stenosis (n = 13 [36.1%], P < .05), and type II muscular injuries were more likely to predispose patients to severe stenosis than type I (73.3% and 92.3%, respectively). The scoring system showed that patients with high scores (3-6) were more likely to have muscular injury. The score model presented good discriminatory power in the internal validation (area under the receiver-operating characteristic curve, .706; 95% confidence interval, .645-.767) and goodness-of-fit in the Hosmer-Lemeshow test (P = .865). CONCLUSIONS: Muscular injury was an independent risk factor for esophageal stenosis. The scoring system demonstrated good performance in predicting muscular injury during ESD.


Assuntos
Carcinoma de Células Escamosas , Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Estenose Esofágica , Humanos , Estenose Esofágica/epidemiologia , Estenose Esofágica/etiologia , Constrição Patológica , Ressecção Endoscópica de Mucosa/efeitos adversos , Estudos Retrospectivos , Neoplasias Esofágicas/cirurgia , Fatores de Risco
6.
Inorg Chem ; 62(14): 5863-5871, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36976914

RESUMO

It is difficult to subject simple reaction starting materials to a "one-pot" in situ tandem reaction without post-treatment under mild reaction conditions to obtain multimers with complex structural linkages. In organic synthesis, acetal reactions are often used to protect derivatives containing carbonyl functional groups. Therefore, acetal products tend to have very low stability, and performing multi-step condensation to obtain complex multimeric products is difficult. Herein, we achieved the first efficient multiple condensation of o-vanillin derivatives using Dy(OAc)3·6H2O undergoing a "one-pot" in situ tandem reaction under mild solvothermal conditions to obtain a series of dimers (I and II, clusters 1 and 2) and trimers (I and II, clusters 3 and 4). When methanol or ethanol is used as the solvent, the alcoholic solvent participates in acetal and dehydration reactions to obtain dimers (I and II). Surprisingly, when using acetonitrile as the reaction solvent, the o-vanillin derivatives undergo acetal and dehydration reactions to obtain trimers (I and II). In addition, clusters 1-4 all showed distinct single-molecule magnetic behaviors under zero-field conditions. To the best of our knowledge, this is the first time that multiple acetal reactions catalyzed by coordination-directed catalysis under "one-pot" conditions have been realized, opening a new horizon for the development of fast, facile, green, and efficient synthetic methods for complex compounds.

7.
Inorg Chem ; 62(48): 19552-19564, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37976457

RESUMO

Pinacol lanthanide complexes PyraLn (Ln = Dy and Tb) with the restriction of intramolecular vibration were obtained for the first time via an in situ solvothermal coordination-catalyzed tandem reaction using cheap and simple starting materials, thereby avoiding complex, time-consuming, and expensive conventional organic synthesis strategies. A high-resolution electrospray ionization mass spectrometry (HRESI-MS) analysis confirmed the stability of PyraLn in an organic solution. The formation process of PyraLn was monitored in detail using time-dependent HRESI-MS, which allowed for proposing a mechanism for the formation of pinacol complexes via in situ tandem reactions under one-pot coordination-catalyzed conditions. The PyraLn complexes constructed using a pinacol ligand with a butterfly configuration exhibited distinct aggregation-induced emission (AIE) behavior, with the αAIE value as high as 60.42 according to the AIE titration curve. In addition, the PyraLn complexes in the aggregated state exhibit a rapid photoresponse to various 3d metal ions with low detection limits. These findings provide fast, facile, and high-yield access to dynamic, smart lanthanide complex emissions with bright emission and facilitate the rational construction of molecular machines for artificial intelligence.

8.
Phys Chem Chem Phys ; 25(37): 25492-25498, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37712358

RESUMO

This article presents a study on tunable narrowband coherent perfect absorption (CPA), which can be altered by adjusting the initial phase to the ranges of 1.03α-1.13α (with α = 2πc/d) and 1.29α-1.43α. The relative bandwidths of these ranges are determined to be 8.5% and 7.4%, respectively. The study utilizes the transfer matrix method for calculations of the largest CPA amplitudes within one-dimensional (1D) magnetized plasma photonic crystals (MPPCs) across two absorption bands, achieving a maximum of 0.99 and 0.98, respectively. In addition, the phase modulation and amplitude modulation characteristics of the CPA are also discussed, and the results show that its absorption amplitude can be gradually modulated from 0.08 to 0.99 by the former and from 0.60 to 0.98 by the latter. The external magnetic fields have also been shown to limit the CPA amplitude between 0.41 and 0.99 within one band and between 0.52 and 0.99 within another band. The study further highlights the effect of plasma frequency and dielectric layer thickness on coherent band shifts towards high or low frequencies. Notably, the article presents the multiband polarization separation properties of 1D MPPCs, with calculated transmittance differences between the TM and TE waves of up to 0.70 and 0.74 at 1.13α and 1.37α, respectively.

9.
Surg Endosc ; 37(12): 9183-9189, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37845536

RESUMO

BACKGROUND AND AIM: Endoscopic resection (ER) has been used to remove submucosal tumors (SMTs) in recent years; however, duodenal ER is associated with high rates of immediate or delayed bleeding and perforation. Whether ER can be recommended for the treatment of duodenal SMTs remains controversial. Therefore, we aimed to investigate the clinical outcomes associated with the ER of duodenal SMTs and to assess possible predictive factors for complications and incomplete resection. METHODS: This retrospective study included 141 patients with duodenal SMTs. The therapeutic outcomes from ER and procedure-related complications were analyzed. RESULTS: Of the 141 patients, 78.7% achieved complete resection and nine (6.4%) developed complications. The multivariate analysis suggested that location near the duodenal papilla (P = 0.010) and diameter exceeding 15 mm (P = 0.091) of duodenal SMTs were independent risk factors for complications in ER. Besides, submucosal fibrosis (P = 0.042), location near the duodenal papilla (P = 0.049), and irregular morphology (P = 0.067) were independent risk factors for incomplete resection. CONCLUSIONS: ER can be recommended as an effective and minimally invasive treatment for duodenal SMTs.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Endoscopia , Fatores de Risco , Ressecção Endoscópica de Mucosa/efeitos adversos , Resultado do Tratamento , Neoplasias Gástricas/cirurgia
10.
Surg Endosc ; 37(8): 6135-6144, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37145172

RESUMO

OBJECTIVE: To evaluate the effectiveness and safety of endoscopic resection and various suturing methods to treat non-ampullary duodenal submucosal tumors (NAD-SMTs). DESIGN: We performed a retrospective observational study of patients with NAD-SMTs who underwent endoscopic resection at Zhongshan Hospital, Fudan University, China, between June 2017 and December 2020. Data on patient characteristics, treatments and follow-up results were collected. The association between clinicopathologic characteristics and different suturing methods or adverse events were analyzed. RESULTS: Of 128 patients analyzed, 26 underwent endoscopic mucosal resection (EMR), 64 underwent endoscopic submucosal excavation (ESE), and 38 underwent endoscopic full-thickness resection (EFTR). EMR and ESR are both appropriate for non-full-thickness lesions, whereas ESE is more appropriate for tumors located in the bulb or descending duodenum. Gastric tube drainage is more strongly recommended after ESE. Satisfactory suturing is also vital endoscopic resection of NAD-SMTs. Metallic clips are often used in EMR or ESE of non-full-thickness lesions. The pathological findings revealed that the full-thickness lesions were predominantly gastrointestinal stromal tumors (GIST), Brunner's tumor or lipoma, and the surgeons usually used purse-string sutures to close the wounds. The operation time was longer for purse-string suture closure than metallic clip closure. Eleven patients had complications. Risk factors for adverse events included large-diameter tumor (≥ 2 cm), location in the descending part of the duodenum, involvement of the fourth layer of the duodenal wall, EFTR, and GIST. CONCLUSIONS: Endoscopic resection of NAD-SMTs is effective but is associated with a high incidence of complications due to their anatomical peculiarities. Preoperative diagnosis is quite important. Careful selection of treatment and suturing methods are necessary to reduce the risk of adverse effects. Given the increased frequency of severe complications during or following duodenal endoscopic resection, this procedure should be performed by experienced endoscopists.


Assuntos
Ressecção Endoscópica de Mucosa , Tumores do Estroma Gastrointestinal , Neoplasias Gástricas , Humanos , Tumores do Estroma Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/patologia , Neoplasias Gástricas/cirurgia , NAD , Resultado do Tratamento , Endoscopia , Ressecção Endoscópica de Mucosa/métodos , Estudos Retrospectivos
11.
Appl Microbiol Biotechnol ; 107(7-8): 2451-2468, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36843199

RESUMO

Maximizing the expression level of therapeutic proteins in cells is the general goal for DNA/mRNA therapies. It is particularly challenging to achieve efficient protein expression in the cellular contexts with inhibited translation machineries, such as in the presence of cellular Nonstructural protein 1 (Nsp1) of coronaviruses (CoVs) that has been reported to inhibit overall protein synthesis of host genes and exogenously delivered mRNAs/DNAs. In this study, we thoroughly examined the sequence and structure contexts of viral and non-viral 5'UTRs that determine the protein expression levels of exogenously delivered DNAs and mRNAs in cells expressing SARS-CoV-2 Nsp1. It was found that high 5'-proximal A/U content promotes an escape from Nsp1-directed inhibition of protein synthesis and results in selective protein expression. Furthermore, 5'-proximal Cs were found to significantly enhance the protein expression in an Nsp1-dependent manner, while Gs located at a specific window close to the 5'-end counteract such enhancement. The distinct protein expression levels resulted from different 5'UTRs were found correlated to Nsp1-induced mRNA degradations. These findings ultimately enabled rational designs for optimized 5'UTRs that lead to strong expression of exogenous proteins regardless of the translationally repressive Nsp1. On the other hand, we have also identified several 5'-proximal sequences derived from host genes that are capable of mediating the escapes. These results provided novel perspectives to the optimizations of 5'UTRs for DNA/mRNA therapies and/or vaccinations, as well as shedding light on the potential host escapees from Nsp1-directed translational shutoffs. KEY POINTS: • The 5'-proximal SL1 and 5a/b derived from SARS-CoV-2 genomic RNA promote exogenous protein synthesis in cells expressing Nsp1 comparing with non-specific 5'UTRs. • Specific 5'-proximal sequence contexts are the key determinants of the escapes from Nsp1-directed translational repression and thereby enhance protein expressions. • Systematic mutagenesis identified optimized 5'UTRs that strongly enhance protein expression and promote resistance to Nsp1-induced translational repression and RNA degradation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Regiões 5' não Traduzidas , SARS-CoV-2/genética , RNA Mensageiro/metabolismo , Linhagem Celular , Proteínas não Estruturais Virais/genética , Biossíntese de Proteínas
12.
Pain Pract ; 23(2): 136-144, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36176201

RESUMO

BACKGROUND: Despite the demonstrated analgesic efficacy of scalp block (SB) during the immediate postoperative period, the impact of SB on pain outcomes at postoperative 24 and 48 h in adults receiving craniotomy remains unclear. METHODS: The databases of Medline, Embase, and Cochrane Central Register were searched from inception to January 2022 for available randomized controlled trials (RCTs). The primary outcome was the severity of pain at postoperative 24 and 48 h, while the secondary outcomes included morphine consumption, hemodynamic profiles after surgical incision and in the postanesthesia care unit (PACU), and risk of postoperative nausea/vomiting (PONV). RESULTS: Meta-analysis of 12 studies revealed a lower pain score [MD = -0.83, p = 0.03, 375 patients, certainty of evidence (COE): low] and morphine consumption (MD = -9.21 mg, p = 0.03, 246 patients, COE: low) at postoperative 24 h, while there were no differences in these pain outcomes at postoperative 48 h (COE: low). The use of SB significantly decreased intraoperative heart rate (MD = -10.9 beats/min, p < 0.0001, 189 patients, COE: moderate) and mean blood pressure (MD = -13.02 mmHg, p < 0.00001, 189 patients, COE: moderate) after surgical incision, but these hemodynamic profiles were comparable in both groups in the PACU setting. There was also no difference in the risk of PONV between the two groups (RR = 0.78, p = 0.2, 299 patients, COE: high). CONCLUSION: This meta-analysis demonstrated that scalp block not only provided hemodynamic stability immediately after surgical incision but was also associated with a lower pain score and morphine consumption at postoperative 24 h. Further studies are needed for elucidation of its findings.


Assuntos
Náusea e Vômito Pós-Operatórios , Ferida Cirúrgica , Adulto , Humanos , Couro Cabeludo/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Morfina , Craniotomia/efeitos adversos , Hemodinâmica , Analgésicos Opioides
13.
BMC Neurol ; 22(1): 129, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35382765

RESUMO

BACKGROUND: To report the main spectrum and new clinical and imaging characteristics of dipeptidyl-peptidase-like protein 6 (DPPX) antibody-associated encephalitis, and to evaluate the effect of immunotherapy. METHODS: A retrospective analysis of nine patients with anti-DPPX encephalitis was performed, and all previously reported cases in the literature were reviewed. A cell-based indirect immunofluorescence assay using human embryonic kidney 293 cells transfected with DPPX was used. RESULTS: Nine patients were identified (median age, 51 years; range, 14-65 years) with prodromal fever, diarrhea, or weight loss, followed by rapid progressive encephalopathy characterized by cognitive disorder. One patient who received methylprednisolone therapy and a trial of tacrolimus showed substantial improvement and had no relapse by the 6-month follow-up. Our comprehensive literature review demonstrated that 53 cases were reported, of which more than half had prodromal weight loss (52.8%) and gastrointestinal disorders (58.5%). Cognitive disorders (74.6%) and brainstem/spinal cord disorders (75.5%) were the most common major symptoms. A greater proportion of Chinese patients than non-Chinese patients had abnormalities on brain magnetic resonance imaging specific for encephalitis (70.0% vs. 23.3%, P < 0.001). Our study is the first to report three patients with anti-DPPX encephalitis who had sleep disorders with rapid eye movement sleep behavior disorder, limb paralysis (two), severe pleocytosis, elevated protein levels (two) in the cerebrospinal fluid, and increased T2/FLAIR signal abnormalities in the bilateral hippocampus, temporal lobe, amygdala, basal ganglia, thalamus, centrum semiovale, and frontal and parietal lobes in seven patients (77.8%). CONCLUSION: Our study expands the clinical and imaging phenotypes of anti-DPPX encephalitis. Further studies elucidating the entire clinical spectrum of anti-DPPX encephalitis, its pathogenic mechanisms, and prognosis under long-term immunosuppressive therapy are warranted.


Assuntos
Encefalite , Canais de Potássio , Autoanticorpos , Encefalite/diagnóstico por imagem , Humanos , Imunoterapia , Imageamento por Ressonância Magnética , Proteínas do Tecido Nervoso , Estudos Retrospectivos
14.
Inorg Chem ; 61(26): 10101-10107, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35709380

RESUMO

Lanthanoid metal ions have large ionic radii, complex coordination modes, and easy distortion of coordination spheres, but the design and synthesis of high-nucleation lanthanoid clusters with high stability in solution (especially aqueous solution) are challenging. Herein, a diacylhydrazone ligand (H2L1) with multidentate chelating coordination sites was used to react with Dy(OAc)3·4H2O under solvothermal conditions to obtain an example of a 34-nucleus crown-shaped dysprosium cluster [Dy34(L)8(µ2-OH)(µ3-OH)21(µ3-O)14(OAc)31(OCH3)2(H2O)15](OAc)3 (1). Structural analysis showed that the bisacylhydrazone ligand H2L1 with polydentate chelate coordination sites could rapidly capture DyIII ions, thereby forming 34-nucleus crown-shaped dysprosium cluster 1 following the out-to-in growth mechanism. Cluster 1 remained stable after immersion in solutions with different pH values (3-14) for 24 h. To the best of the authors' knowledge, high-nucleation lanthanoid clusters with excellent strong acid and base stability and water stability are very rare. Meanwhile, high-resolution electrospray mass spectrometry molecular ion peaks produced by cluster 1 were captured, which proved to be stable also in organic solvents. Magnetic research showed that cluster 1 exhibited frequency-dependent behavior. This work provides a new idea for designing and synthesizing high-nucleation lanthanoid clusters with high stability.

15.
Inorg Chem ; 61(16): 6094-6100, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35416660

RESUMO

A three-dimensional supermolecule structure is easily formed due to the diverse coordination modes of high-oxidation-state lanthanide metal ions. However, the design and construction of zero-dimensional (0 D) dish-shaped high-nuclearity lanthanide clusters are difficult. Herein, for the first time, we synthesized a series of the largest dish-shaped high-nuclearity lanthanide nanoclusters (1-4) by in situ tandem reactions under solvothermal one-pot conditions. The formation of 1 and 2 involved an in situ reaction of aldehydes and amines, while the condensation reactions between aldehydes occurred in 3 and 4. Based on the structural characteristics of the dish-shaped lanthanide clusters, we proposed two possible assembly mechanisms involving Dy1 → Dy7 → Dy13 → Dy19 (planar epitaxial growth mechanism) and Dy1 → Dy12 → Dy18 → Dy19 (planar internal growth mechanism).

16.
Inorg Chem ; 61(8): 3655-3663, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35167747

RESUMO

A full understanding of the assembly mechanisms of coordination complexes is of great importance for a directional synthesis under control. We thus explored here the formation mechanisms of the two new heterometallic nanoclusters [DyIII4NiII8(µ3-OH)8(L)8(OAc)4(H2O)4]·3.25EtOH·4CH3CN (1) and [DyIII10MnIII4MnII2O4(OH)12(OAc)16(L)4(HL)2(EtOH)2]·2EtOH·2CH3CN·2H2O (2) with different cubane-based squarelike ring structures, which were obtained from the reactions of 4-bromo-2-[(2-hydroxypropylimino)methyl]phenol (H2L) with Dy(NO)3·6H2O and the transition metal salt Ni(OAc)2·4H2O or Mn(OAc)2·4H2O. The high-resolution electrospray ionization mass spectrometry (HRESI-MS) tests showed that the skeletons of clusters 1 and 2 have a high stability under the measurement conditions for HRESI-MS. The intermediates formed in the reaction courses of clusters 1 and 2 were tracked using time-dependent HRESI-MS, which helped to determine the proposed hierarchical assembly mechanisms for 1 (H2L → NiL → Ni2L2 → Ni3L4 → Ni4L4 → DyNi4L5 → Dy2Ni6L6 → Dy3Ni6L6 → Dy3Ni7L7 → Dy4Ni8L8) and 2 (H2L → MnL → DyMnL → DyMn2L → Dy2Mn2Lx → Dy8Mn2L2 → Dy10Mn2L2 → Dy10Mn6Lx and H2L → DyL → Dy4L2 → Dy6L2 → Dy8Mn2L2 → Dy10Mn2L2 → Dy10Mn6Lx). This is one of the rare examples of investigating the assembly mechanisms of 3d-4f heterometallic clusters. Magnetic studies indicated that the title complexes both show slow magnetic relaxation behaviors and cluster 1 is a field-induced single-molecule magnet.

17.
Inorg Chem ; 61(50): 20513-20523, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36475643

RESUMO

By changing the coordination anions (OAc- and Cl-), reaction temperature, solvent, and ligand substituents, four Dy(III)-based complexes were obtained by directed synthesis, which are [Dy4(L1)2(L2)2(OAc)4]·4C2H5OH·3H2O (1, L1 = 1,3,4-thiadiazole-2,5-diamine, H4L2 = 6,6'-(((1,3,4-thiadiazole-2,5-diyl)bis(azanediyl))bis(((3-ethoxy-2-hydroxybenzyl)oxy)methylene))bis(2-ethoxyphen), [Dy4(L3)4(OAc)4]·C2H5OH·H2O (2, H3L3 = 2-(((5-amino-1,3,4-thiadiazol-2-yl)amino)((3-ethoxy-2-hydroxybenzyl)oxy)methyl)-6-ethoxyphenol)), [Dy6(L4)4(L5)2(µ3-OH)4(CH3O)4Cl4]Cl2 (3, H2L4 = 2-hydroxy-3-methoxybenzaldehyde, H2L5 = 2-(((5-amino-1,3,4-thiadiazol-2-yl)amino)(hydroxy)methyl)-6-methoxyphenol), and [Dy6(L6)4(L7)2(µ3-OH)4(CH3O)4Cl4]Cl2·2H3O (4, H2L6 = 2-hydroxy-3-ethoxybenzaldehyde, H2L7 = 2-(((5-amino-1,3,4-thiadiazol-2-yl)amino)(hydroxy)methyl)-6-ethoxyphenol). A series of acetal products (H4L2, H3L3, H2L5, and H2L7) were obtained through dehydration in situ tandem reactions. Magnetic studies show that complexes 1-4 exhibited different single-molecule magnet behavior under zero-field conditions. The best fitting results showed that under zero DC field, the effective energy barriers (Ueff) and magnetic relaxation times (τ0) of complexes 1-4 are Ueff = 117.0 (2.1) K and τ0 = 6.07 × 10-7 s; Ueff = 83.91 (1.5) K and τ0 = 4.28 × 10-7 s; Ueff = 1.28 (0.2) K and τ0 = 0.73 s, and Ueff = 104.43 (13.3) K and τ0 = 8.25 × 10-8 s, respectively.

18.
Inorg Chem ; 61(49): 20169-20176, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36445983

RESUMO

Widespread concern has been raised over the synthesis of highly nucleated lanthanide clusters with special shapes and/or specific linkages. Construction of lanthanide clusters with specific shapes and/or linkages can be achieved by carefully regulating the hydrolysis of lanthanide metal ions and the resulting hydrolysis products. However, studies on the manipulation of lanthanide-ion hydrolysis to obtain giant lanthanide-oxo clusters have been few. In this study, we obtained a tetraicosa lanthanide cluster (3) by manipulating the hydrolysis of Dy(III) ions using an anion (OAc-). As far as we know, cluster 3 has the highest nucleation among all lanthanide-oxo clusters reported. In 3, two triangular Dy3O4 are oriented in opposite directions to form the central connecting axis Dy6(OH)8, which is in turn connected to six Dy3O4 that are oriented in different directions. Meanwhile, a sample of a chiral trinuclear dysprosium cluster (1) was obtained in a mixed CH3OH and CH3CN solvent and by replacing the anion in the reaction to Cl- ions. In this cluster, 1,3,4-thiadiazole-2,5-diamine (L2) is free on one side through π···π interactions and is parallel to the o-vanillin (L1)- ligand, thus resulting in a triangular arrangement. The arrangement of L2 affects the end group coordination in the cluster 1 structure through hydrogen bonding and induces the cluster to exhibit chirality. When the reaction solvent was changed to CH3OH, a sample of cluster 2, composed of two independent triangular Dy3 that have different end group arrangements, was obtained. Magnetic analysis showed that clusters 1 and 3 both exhibit distinctive single-molecule magnetic properties under zero-magnetic-field conditions. This study thus provides a method for the creation of chiral high-nucleation clusters from achiral ligands and potentially paves the way for the synthesis of high-nucleation lanthanide clusters with unique forms.


Assuntos
Elementos da Série dos Lantanídeos , Elementos da Série dos Lantanídeos/química , Ânions , Ligantes , Hidrólise , Íons
19.
Acta Haematol ; 145(5): 484-498, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35313299

RESUMO

INTRODUCTION: Chronic myeloid leukaemia (CML) is a myeloproliferative neoplasm characterized by constitutive activity of the tyrosine kinase BCR-ABL1. Drug resistance remains one of the major challenges in CML therapy. MicroRNA (miR)-199a-3p plays an important role in many tumours but has rarely been investigated in CML. We aimed to analyse the role and mechanism of miR-199a-3p in regulating imatinib resistance in CML. METHODS: The expression of miR-199a-3p and mammalian target of rapamycin (mTOR) in the serum of CML patients and CML cells was examined by quantitative real-time polymerase chain reaction. The levels of apoptosis-related proteins were determined using western blot. The relative cell survival rate and cell proliferation were determined using a CCK-8 assay and a bromodeoxyuridine (BrdU) assay, respectively. Cell cycle and apoptosis were analysed using flow cytometry. Moreover, a dual-luciferase reporter assay was performed to verify the correlation between miR-199a-3p and mTOR. RESULTS: MiR-199a-3p was downregulated in the serum of CML patients and in CML cells, while mTOR was upregulated. Both miR-199a-3p overexpression and mTOR silencing inhibited CML cell proliferation, promoted CML cell apoptosis, and sensitized these cells to imatinib. mTOR silencing reversed the promoting effect of miR-199a-3p inhibition on the proliferation of CML cells and the inhibitory effects on cell apoptosis and sensitivity to imatinib. MiR-199a-3p directly targeted mTOR. CONCLUSION: MiR-199a-3p suppressed cell propagation, facilitated apoptosis of CML cells, and sensitized CML cells to imatinib by downregulating mTOR signalling.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , MicroRNAs , Apoptose , Bromodesoxiuridina/farmacologia , Bromodesoxiuridina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Luciferases/farmacologia , Luciferases/uso terapêutico , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Tirosina Quinases , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/farmacologia
20.
BMC Pregnancy Childbirth ; 22(1): 406, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562679

RESUMO

BACKGROUND: Literature suggests that nonobstetric surgery during gestation is associated with a higher risk of spontaneous abortion, prematurity, and a higher cesarean section rate, but the direct impact on fetal outcomes is still unclear. In this study, we aimed to investigate whether nonobstetric surgery during pregnancy is associated with negative fetal outcomes by analysing a nation-wide database in Taiwan. METHODS: This population-based retrospective observational case-control study was based on the linkage of Taiwan's National Health Insurance Research Database, Birth Reporting Database, and Maternal and Child Health Database between 2004 and 2014. For every pregnancy with nonobstetric surgery during gestation, four controls were randomly matched according to maternal age and delivery year. We estimated adjusted odds ratios (aOR) and 95% confidence intervals (CIs) of adverse fetal outcomes with the non-surgery group as the reference. The primary outcomes involved stillbirth, prematurity, low birth weight, low Apgar scores, and neonatal and infant death. RESULTS: Among 23,721 identified pregnancies, 4,747 underwent nonobstetric surgery. Pregnancies with nonobstetric surgery had significantly higher risks of prematurity (aOR: 1.46; 95% CI: 1.31-1.62), lower birth weight (aOR: 1.49; 95% CI: 1.33-1.67), Apgar scores < 7 (1 min, aOR: 1.58; 95% CI: 1.33-1.86; 5 min, aOR: 1.34; 95% CI: 1.03-1.74), neonatal death (aOR: 2.01; 95% CI: 1.18-3.42), and infant death (aOR: 1.69; 95% CI: 1.12-2.54) than those without nonobstetric surgery after adjustment for socioeconomic deprivation, hospital level, and other comorbidities. Surgery performed in the third trimester was associated with a significantly increased rate of prematurity (aOR: 1.38; 95% CI: 1.03-1.85), but lower rates of stillbirth (aOR: 0.1; 95% CI: 0.01-0.75) and Apgar score < 7 at the 5th minute (aOR: 0.2; 95% CI: 0.05-0.82), than surgery performed in the first trimester. CONCLUSIONS: Pregnancies with nonobstetric surgery during gestation were associated with increased risks of prematurity, low birth weight, low Apgar scores, neonatal and infant death, longer admission, and higher medical expenses than those without surgery. Furthermore, surgery in the third trimester was associated with a higher rate of prematurity than surgery performed in the first trimester. TRIAL REGISTRATION: Not applicable.


Assuntos
Nascimento Prematuro , Natimorto , Estudos de Casos e Controles , Cesárea/efeitos adversos , Criança , Feminino , Humanos , Lactente , Morte do Lactente , Recém-Nascido , Gravidez , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Estudos Retrospectivos , Natimorto/epidemiologia
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