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1.
J Am Chem Soc ; 146(20): 14341-14348, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38726476

RESUMO

Phosphagermylenylidenes (R-P═Ge), as heavier analogs of isonitriles, whether in their free state or as complexes with a Lewis base, have not been previously identified as isolable entities. In this study, we report the synthesis of a stable monomeric phosphagermylenylidene within the coordination sphere of a Lewis base under ambient conditions. This species was synthesized by Lewis base-induced dedimerization of a cyclic phosphagermylenylidene dimer or via Me3SiCl elimination from a phosphinochlorogermylene framework. The deliberate integration of a bulky, electropositive N-heterocyclic boryl group at the phosphorus site, combined with coordination stabilization by a cyclic (alkyl)(amino)carbene at the low-valent germanium site, effectively mitigated its natural tendency toward oligomerization. Structural analyses and theoretical calculations have demonstrated that this unprecedented species features a P═Ge double bond, characterized by conventional electron-sharing π and σ bonds, complemented by lone pairs at both the phosphorus and germanium atoms. Preliminary reactivity studies show that this base-stabilized phosphagermylenylidene demonstrates facile release of ligands at the Ge atom, coordination to silver through the lone pair on P, and versatile reactivity including both (cyclo)addition and cleavage of the P═Ge double bond.

2.
Opt Lett ; 49(1): 69-72, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134154

RESUMO

Insensitivity to external optical feedback is experimentally demonstrated in a self-chaotic deformed square microcavity laser for the first time, to the best of our knowledge. Both the optical and radio frequency (RF) spectra of the microlaser remain unaffected for external optical feedback with feedback strength as high as 9.9 dB. In addition, the autocorrelation function curve exhibits no time-delayed peaks. The insensitivity makes the self-chaotic microcavity laser promising for applications in feedback-insensitive optical sources.

3.
J Biochem Mol Toxicol ; 38(1): e23551, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37983895

RESUMO

Esophageal cancer (EC) is a challenging tumor to treat with radiotherapy, often exhibiting resistance to this treatment modality. To explore the factors influencing radioresistance, we focused on the role of hypoxia-induced factor-1α (HIF-1α), and its interaction with the long noncoding RNA long intergenic nonprotein coding RNA 1116 (LINC01116). We analyzed the LINC01116 expression in EC and EC cell lines/human normal esophageal epithelial cell line (Het-1A). LINC01116 was silenced/overexpressed in EC109/KYSE30 cells under hypoxia, followed by radioresistance assessment. We measured HIF-1α levels in hypoxic EC cells and further validated the binding of HIF-1α with LINC01116, analyzing their interaction in EC cells. We then performed experiments in EC109 cells by transfection them with sh-HIF-1α/oe-LINC01116 to verify the effects. Additonally, we analyzed the localization of LINC01116 and its binding with miR-3612, followed by a combined experiment performed to validate the results. Our findings indicated that LINC01116 was highly expressed in EC and further elevated in hypoxic EC cells. LINC01116 was expressed at a high level in EC, which was further elevated in EC cells under hypoxic conditions. Knockdown of LINC01116 triggered EC cell apoptosis, thus suppressing radioresistance. Further investigation revealed that HIF-1α transcriptionally activated LINC01116 expression under hypoxia, and silencing HIF-1α lowered EC cell radioresistance by downregulating LINC01116. Under hypoxic conditions, LINC01116 could function as a sponge for miR-3612 and inhibit its expression. This interaction between LINC01116 and miR-3612 played a crucial role in mediating radioresistance in EC cells. Briefly, under hypoxic conditions, HIF-1α facilitates radioresistance of EC cells by transcriptionally activating LINC01116 expression and downregulating miR-3612.


Assuntos
Neoplasias Esofágicas , MicroRNAs , Humanos , Hipóxia Celular/genética , Linhagem Celular Tumoral , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/metabolismo , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , RNA não Traduzido/genética
4.
Appl Opt ; 63(1): 154-158, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175016

RESUMO

A self-chaotic circular-sided square microcavity laser, with a chaos bandwidth of 12.9 GHz and a flatness of ±3d B, was applied in optical time domain reflectometry (OTDR). Using the broadband chaos laser, we demonstrated a range resolution of 4.5 mm and a 25-km detection distance experimentally. The solitary wide-bandwidth microcavity chaos laser, without the extra correlation peaks in optical feedback chaotic lasers, has shown potential advantages for correlation OTDR in practical application.

5.
Opt Lett ; 48(19): 4953-4956, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773358

RESUMO

Self-pulsing and dual-mode lasing in a square microcavity semiconductor laser are studied experimentally. Self-sustained pulses originating from undamped relaxation oscillation induced by a two-mode interaction are obtained, as the injection current is slightly above the laser threshold. A repetition frequency of 4.4 GHz and a pulse width of 30-40 ps are obtained at a current of 8 mA. The laser switches to continuous-wave operation when the injection current is higher than a certain value, and dual-mode lasing with 30.7 GHz at 16 mA and 10.7 GHz at 27 mA are observed in the lasing spectra. Furthermore, the relative intensity noise spectra are presented to reveal the relationship between the lasing states and the dynamics induced by relaxation oscillation and mode beating.

6.
BMC Cancer ; 23(1): 597, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380982

RESUMO

BACKGROUND: The nutritional status of cancer patients is a crucial factor in determining their prognosis. The objective of this study was to investigate and compare the prognostic value of pretreatment nutrition-related indicators in elderly esophageal squamous cell carcinoma (ESCC). Risk stratification was performed according to independent risk factors and a new nutritional prognostic index was constructed. METHODS: We retrospectively reviewed 460 older locally advanced ESCC patients receiving definitive chemoradiotherapy (dCRT) or radiotherapy (dRT). This study included five pre- therapeutic nutrition-related indicators. The optimal cut-off values for these indices were calculated from the Receiver Operating Curve (ROC). Univariate and multivariate COX analyses were employed to determine the association between each indicator and clinical outcomes. The predictive ability of each independently nutrition-related prognostic indicator was assessed using the time-dependent ROC (time-ROC) and C-index. RESULTS: Multivariate analyses indicated that the geriatric nutrition risk index (GNRI), body mass index (BMI), the controlling nutritional status (CONUT) score, and platelet-albumin ratio (PAR) could independently predict overall survival (OS) and progression-free survival (PFS) in elderly patients with ESCC (all p < 0.05), except for prognostic nutritional index (PNI). Based on four independently nutrition-related prognostic indicators, we developed pre-therapeutic nutritional prognostic score (PTNPS) and new nutritional prognostic index (NNPI). No-risk (PTNPS = 0-1 point), moderate-risk (PTNPS = 2 points), and high-risk (PTNPS = 3-4 points) groups had 5-year OS rates of 42.3%, 22.9%, and 8.8%, respectively (p < 0.001), and 5-year PFS rates of 44.4%, 26.5%, and 11.3%, respectively (p < 0.001). The Kaplan-Meier curves showed that the mortality of elderly ESCC patients in the high-risk group was higher than that in the low-risk group according to the NNPI. Analysis of time-AUC and C-index revealed that the NNPI (C-index: 0.663) had the greatest predictive power on the prognosis in older ESCC patients. CONCLUSIONS: In elderly ESCC patients, the GNRI, BMI, CONUT score, and PAR can be used as objective assessment measures for the risk of nutrition-related death. Compared to the other four indexes, the NNPI has the greatest prognostic value for prognosis, and elderly patients with a higher nutritional risk have a poor prognosis, which is helpful in guiding early clinical nutrition intervention.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Idoso , Humanos , Prognóstico , Carcinoma de Células Escamosas do Esôfago/terapia , Neoplasias Esofágicas/terapia , Estudos Retrospectivos , Quimiorradioterapia , Fatores de Risco , Albuminas
7.
BMC Cancer ; 23(1): 1193, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053017

RESUMO

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) by routine hematoxylin and eosin staining (H&E-TILs) are a robust prognostic biomarker in various cancers. However, the role of H&E-TILs in esophageal squamous cell carcinoma (ESCC) treated with concurrent chemoradiotherapy (CCRT) has not been reported. The purpose of this study was to assess the prognostic value of H&E-TILs in ESCC treated with CCRT. METHODS: The clinical data of 160 patients with ESCC treated with CCRT in our center between Jan. 2014 and Dec. 2021 were collected and retrospectively reviewed, and propensity score matching (PSM) analyses were performed. The H&E-TILs sections before CCRT were reassessed by two experienced pathologists independently. The H&E-TILs sections were classified into a positive group (+, > 10%) and a negative group (-, ≤ 10%) using 10% as the cutoff. The effects of H&E-TILs on overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and locoregional recurrence-free survival (LRFS) were explored using the Kaplan‒Meier method, and the log-rank test was used to test the differences. Multivariable analysis was performed using the Cox proportion hazards model. RESULTS: The short-term response to CCRT and the OS (P < 0.001), DMFS (P = 0.001), and LRFS (P < 0.001) rates were significantly different between the H&E-TILs (+) and H&E-TILs (-) groups. Subgroup analysis showed that H&E-TILs(+) with CR + PR group had a longer survival than H&E-TILs(-) with CR + PR, H&E-TILs(+) with SD + PD and H&E-TILs(-) with SD + PD group, respectively(P < 0.001). Furthermore, based on TCGA data, patients in the high TILs group had a better prognosis than those in the low TILs group. Multivariate analyses indicated that H&E-TILs and the short-term response to CCRT were the only two independent factors affecting OS, PFS, DMFS, and LRFS simultaneously, and H&E-TILs expression was associated with an even better prognosis for those patients with CR + PR. CONCLUSIONS: H&E-TILs may be an effective and beneficial prognostic biomarker for ESCC patients treated with CCRT. Patients with H&E-TILs (+) with PR + CR would achieve excellent survival. Further prospective studies are required to validate the conclusions.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/patologia , Prognóstico , Amarelo de Eosina-(YS) , Hematoxilina , Linfócitos do Interstício Tumoral/patologia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patologia , Estudos Retrospectivos , Quimiorradioterapia/métodos , Biomarcadores
8.
Genet Res (Camb) ; 2023: 7129325, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497166

RESUMO

Background: Advanced glycation end products' receptor (AGER) is a multiligand receptor that interacts with a wide range of ligands. Previous studies have shown that abnormal AGER expression is closely related to immune infiltration and tumorigenesis. However, the AGER DNA methylation relationship between prognosis and infiltrating immune cells in LUAD and LUSC is still unclear. Methods: AGER expression in pan-cancer was obtained by using the UALCAN databases. Kaplan-Meier plotter showed the correlation of AGER mRNA expression levels and clinicopathological parameters. The protein expression levels for AGER were derived from Human Protein Atlas Database Analysis. The copy number, somatic mutation, and DNA methylation of AGER were presented with UCSC Xena database. TIMER platform and TISIDB website were used to show the correlation between AGER expression and tumor immune cell infiltration level. Results: The expression level of AGER was significantly reduced in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). Low expression of AGER was significantly correlated with histology, stage, lymph node metastasis, and tumor protein 53 (TP53) mutation and could be used as a potential indicator of poor prognosis of LUAD and LUSC. Moreover, AGER expression was positively correlated with the infiltrating immune cells. Further analysis showed that copy number variation (CNV), mutation, and DNA methylation were involved in AGER downregulation. In addition, we also found that hypermethylated AGER was significantly correlated with tumor-infiltrating lymphocytes. Conclusion: AGER may be a candidate for the prognostic biomarker of LUAD and LUSC related to tumor immune microenvironment.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Bases de Dados de Proteínas , Variações do Número de Cópias de DNA/genética , Metilação de DNA/genética , Produtos Finais de Glicação Avançada , Pulmão , Neoplasias Pulmonares/genética , Prognóstico , Microambiente Tumoral/genética
9.
Int J Clin Oncol ; 28(4): 550-564, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36735115

RESUMO

OBJECTIVE: The purpose of this study was to compare the clinical outcomes and toxicities between induction chemotherapy (IC) + chemo-radiotherapy (CRT) and CRT alone in patients with locally advanced esophageal squamous cell carcinoma (ESCC), to explore the appropriate thoracic radiotherapy (TRT) timing after IC and to identify prognostic factors. METHODS: 450 ESCC patients were included from September 2011 to December 2020, 238 of whom received IC/CRT. Propensity score matching was performed to balance potential confounders between the two groups. Multivariate Cox regression analysis was used to identify the independent prognostic factors. RESULTS: Patients who received IC/CRT experienced improved overall survival (OS) (38.5 vs. 28.8 months) and progression-free survival (PFS) (41.0 vs. 22.0 months) before matching, with similar results after matching. In the IC/CRT group, early TRT had more favorable survival than late TRT both matching before and after. In subgroup analysis, early TRT combination concurrent chemotherapy had better OS and PFS than late TRT combination concurrent chemotherapy. In addition, early TRT had better survival benefits regardless of the N stage. Notably, the IC/CRT group and early TRT group had manageable toxicities reaction compared with CRT alone group and the late TRT group. The nomogram was developed to predict the OS and PFS based on multivariate analysis results. The C-index was 0.743 and 0.722, respectively. CONCLUSION: IC/CRT and early TRT could yield satisfactory clinical outcomes and controllable toxicities in locally advanced ESCC. The IC plus early concurrent CRT might be a promising treatment strategy for improving further survival in ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/radioterapia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Quimioterapia de Indução/efeitos adversos , Quimiorradioterapia/efeitos adversos , Estudos Retrospectivos
10.
Clin Oral Investig ; 27(11): 6597-6606, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37736812

RESUMO

OBJECTIVE: To determine factors influencing survival and prognosis of HPV-related and non-related oropharyngeal cancer. METHODS: Subjects were determined from the three hospitals in Anhui province of China between 2015 and 2020. Paraffin-embedded specimens from participants' tissues were analyzed, and the subjects were classified as P16 + and P16 - cases using immunohistochemical staining for P16 protein. RESULTS: A total of 426 patients with oropharyngeal cancer were recruited in this study; 108 cases were found to be P16 + . The subjects were treated with the three regimens: surgery/radiotherapy/chemotherapy (SRCT), radiotherapy/chemotherapy (RCT), and surgery/chemotherapy (SCT). There were no statistically significant differences in the survival rates within the P16 + or P16 - groups between the three treatment regimens (P > 0.05). The 1-, 3-, and 5-year survival rates for P16 + and P16 - groups were statistically different (P < 0.05). Multivariate analysis showed that age, physical health status, smoking, and alcohol abuse were independent risk factors affecting the prognosis of P16 + cases, while pathological grading and TNM staging were independent risk factors affecting the P16 - cases. CONCLUSION: The etiology, pathogenesis, survival status, and prognostic factors of HPV-related oropharyngeal cancer are very different from those of traditional oropharyngeal cancer. Thus, HPV-related oropharyngeal cancer could be classified as a separate type of disease. This distinction could be of great significance for treatment, prevention, and prognostication of oropharyngeal cancer.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Estudos Retrospectivos , Carcinoma de Células Escamosas/patologia , Prognóstico , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/terapia
11.
J Craniofac Surg ; 34(5): e474-e477, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37185316

RESUMO

OBJECTIVE: This study aimed to investigate the survival quality of peroneal artery perforator flap in the reconstruction of oral and maxillofacial malignant tumors. METHODS: Thirty-two cases with a diagnosis of oral and maxillofacial malignant tumors admitted to our hospital from January 2019 to December 2019 were randomly divided into 2 groups. The observation group was reconstructed with free open artery perforator flaps, and the control group was repaired with free forearm flaps. RESULTS: The observation group had significantly lower scores in terms of postoperative pain, appearance, and anxiety, compared with the control group ( P <0.05). Both groups had high scores on taste, saliva, and shoulder function although there was no significant difference ( P >0.05). The scores of the observation group were significantly higher than those in the control group in terms of chewing, swallowing, speech, activity, mood, and entertainment ( P <0.05). There was 1 case accompanied by postoperative wound dehiscence and 2 cases with wound infection in the observation group while there were 3 cases with wound dehiscence and 2 cases with wound infection in the control group ( P >0.05). CONCLUSION: Compared with the forearm flap, the peroneal artery perforator flap can improve the survival quality of patients, especially in postoperative function with the fibula joint to repair the oral and maxillofacial defects. It has a wide application prospect as one of the ideal flaps in oral and maxillofacial postoperative repair and reconstruction.


Assuntos
Neoplasias , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Neoplasias/cirurgia , Retalho Perfurante/cirurgia , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Artérias da Tíbia , Resultado do Tratamento
12.
Pharm Biol ; 61(1): 897-906, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37288729

RESUMO

CONTEXT: Plantamajoside (PMS) possesses rich pharmacological characteristics that have been applied to remedy dozens of diseases. However, the understanding of PMS in sepsis remains insufficient. OBJECTIVE: Role of PMS in sepsis-regulated organ dysfunction and potential mechanisms were investigated. MATERIALS AND METHODS: Thirty C57BL/6 male mice were adaptive fed for three days and used to establish acute sepsis model by caecal ligation and perforation (CLP). These experimental mice were divided into Sham, CLP, CLP + 25 mg PMS/kg body weight (PMS/kg), CLP + 50 mg PMS/kg and CLP + 100 mg PMS/kg (n = 6). The pathological and apoptotic changes of lung, liver and heart tissues were observed via HE and TUNEL staining. The injury-related factors of lung, liver and heart were detected by corresponding kits. ELISA and qRT-PCR were applied to assess IL-6/TNF-α/IL-1ß levels. Apoptosis-related and TRAF6/NF-κB-related proteins were determined using Western blotting. RESULTS: All doses of PMS enhanced the survival rates in the sepsis-induced mouse model. PMS remitted sepsis-mediated lung, liver and heart injury through prohibiting MPO/BALF (70.4%/85.6%), AST/ALT (74.7%/62.7%) and CK-MB/CK (62.3%/68.9%) levels. Moreover, the apoptosis index (lung 61.9%, liver 50.2%, heart 55.7% reduction) and IL-6/TNF-α/IL-1ß levels were suppressed by PMS. Furthermore, PMS lowered TRAF6 and p-NF-κB p65 levels, whereas TRAF6 overexpression reversed the protective influences of PMS in organ injury, apoptosis and inflammation triggered by sepsis. DISCUSSION AND CONCLUSIONS: PMS suppressed sepsis-induced organ dysfunction by regulating the TRAF6/NF-κB axis, and PMS treatment may be considered as a novel strategy for sepsis-caused damage in future.


Assuntos
NF-kappa B , Sepse , Camundongos , Masculino , Animais , NF-kappa B/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Insuficiência de Múltiplos Órgãos/tratamento farmacológico , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/prevenção & controle , Camundongos Endogâmicos C57BL , Sepse/complicações , Sepse/tratamento farmacológico
13.
Angew Chem Int Ed Engl ; 62(49): e202315249, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37877345

RESUMO

Discovering new bonding scenarios and subsequently exploring the reactivity contribute substantially to advance the main group element chemistry. Herein, we report on the isolation and characterization of an intriguing class of the hydrido-benzosiloles 2-4. These compounds exhibit a side arm of the amidinatosilylenyl group, featuring unidirectional silicon(II)/silicon(IV) donor-acceptor interaction on account of the geometric constraint. Furthermore, the reactions involving 2-4 with nitriles yield the tricyclic compounds that edge-fused of the Si-heteroimidazolidine-CN2 Si2 , silole-C4 Si, and phenyl-C6 -rings (5-13). These compounds are manifesting a unique reaction that the silicon(II)/silicon(IV) interaction enables the enamination of the α-H-bearing nitriles. The reaction mechanism involved in H-shift under oxidative addition at silylene followed by hydrosilylation of a ketenimine intermediate was revealed by density function theory (DFT) calculations.

14.
J Am Chem Soc ; 144(51): 23691-23697, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36520955

RESUMO

Free phosphaborenes (R-P═B-R) are PB analogues of alkynes, and their isolation is a long-sought-after goal. Herein, we demonstrate that the combination of a π-donating and a π-accepting substituent with bulky flanking arene rings enables the isolation of a crystalline free phosphaborene 5 at room temperature. This electron push-pull cooperation, combined with the kinetic protection, hinders its inherent tendency to oligomerize. This species features a PB double bond consisting of a conventional σ bond and a delocalized π bond. The lone pair of electrons at P slightly contributes to the PB bonding. Preliminary reactivity studies show that 5 undergoes facile (cyclo)addition reactions with p-methyl benzaldehyde, p-fluoroacetophenone, and carbon disulfide, the last of which results in facile PB double bond cleavage. Our strategy has a significant impact on the future synthesis of ambiphilic heterodiatomic multiply bonded main group species.


Assuntos
Alcinos , Elétrons , Temperatura , Alcinos/química
15.
Chemistry ; 28(5): e202103715, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34837718

RESUMO

Electron-transferable oxidants such as B(C6 F5 )3 /nBuLi, B(C6 F5 )3 /LiB(C6 F5 )4 , B(C6 F5 )3 /LiHBEt3 , Al(C6 F5 )3 /(o-RC6 H4 )AlH2 (R=N(CMe2 CH2 )2 CH2 ), B(C6 F5 )3 /AlEt3 , Al(C6 F5 )3 , Al(C6 F5 )3 /nBuLi, Al(C6 F5 )3 /AlMe3 , (CuC6 F5 )4 , and Ag2 SO4 , respectively were employed for reactions with (L)2 Si2 C4 (SiMe3 )2 (C2 SiMe3 )2 (L=PhC(NtBu)2 , 1). The stable radical cation [1]+. was formed and paired with the anions [nBuB(C6 F5 )3 ]- (in 2), [B(C6 F5 )4 ]- (in 3), [HB(C6 F5 )3 ]- (in 4), [EtB(C6 F5 )3 ]- (in 5), {[(C6 F5 )3 Al]2 (µ-F)]- (in 6), [nBuAl(C6 F5 )3 ]- (in 7), and [Cu(C6 F5 )2 ]- (in 8), respectively. The stable dication [1]2+ was also generated with the anions [EtB(C6 F5 )3 ]- (9) and [MeAl(C6 F5 )3 ]- (10), respectively. In addition, the neutral compound [(L)2 Si2 C4 (SiMe3 )2 (C2 SiMe3 )2 ][µ-O2 S(O)2 ] (11) was obtained. Compounds 2-11 are characterized by UV-vis absorption spectroscopy, X-ray crystallography, and elemental analysis. Compounds 2-8 are analyzed by EPR spectroscopy and compounds 9-11 by NMR spectroscopy. The structure features are discussed on the central Si2 C4 -rings of 1, [1]+. , [1]2+ , and 11, respectively.

16.
BMC Cancer ; 22(1): 1132, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333719

RESUMO

BACKGROUND: N7-Methylguanosine (m7G) and long non-coding RNAs (lncRNAs) have been widely studied in cancer and have been found to be useful for assessing tumor progression. However, the role of m7G-related lncRNAs in lung squamous cell carcinoma (LUSC) remains unclear. Thus, it is crucial to identify m7G-associated lncRNAs with definitive prognostic value. This study aimed to investigate the prognostic value, correlation with tumor mutation burden, and impact on the tumor immune microenvironment of m7G-related lncRNAs in LUSC.  METHODS: LUSC transcriptome data and clinical data were downloaded from The Cancer Genome Atlas, and an m7G-related lncRNA-mRNA co-expression network was constructed using Pearson's correlation analysis. Cox regression analyses were used to determine a risk model for m7G-associated lncRNAs with prognostic value. The risk signature was verified using the Kaplan-Meier method, receiver operating characteristic curve analysis, and principal component analysis. A nomogram based on risk scores and clinical characteristics was then developed. Gene set enrichment analysis was used for functional annotation to analyze the risk signature. The association among the risk signature, tumor mutational burden, and tumor-infiltrating immune cells was then analyzed. RT-qPCR was used to investigate the expression of 6 m7G-related lncRNAs in LUSC cells. The cytological function of SRP14-AS1 was verified by wound-healing assay and transwell assay. RESULTS: A total of 293 m7G-related lncRNAs were identifed, 27 candidate m7G-related lncRNAs were signifcantly associated with overall survival (OS). Six of these lncRNAs (CYP4F26P, LINC02178, MIR22HG, SRP14-AS1, TMEM99, PTCSC2) were selected for establishment of the risk model. The OS of patients in the low-risk group was higher than that of patients in the high-risk group (p < 0.001). Multivariate cox regression analysis indicated that the model could be an independent prognostic factor for LUSC (HR = 1.859; 95% CI 1.452-2.380, p < 0.001). The ROC curve analysis revealed that the AUCs for OS in the 3-, and 5-year were 0.682, 0.657, respectively. GSEA analysis revealed that the risk model was closely related to immune-related pathways. Compared with normal lung epithelial cells, four m7G-related lncRNAs were higher expressed in cancer cells and two were lower expressed, among which knockdown of SRP14-AS1 promoted the proliferation and migration of LUSC cells. CONCLUSION: A risk model based on six m7G-related lncRNAs with prognostic value may be a promising prognostic tool in LUSC and guide individualized patient treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/patologia , Prognóstico , Carcinoma de Células Escamosas/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Pulmão/patologia , Microambiente Tumoral/genética
17.
BMC Cancer ; 22(1): 117, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35090419

RESUMO

BACKGROUND: Calcium-activated nucleotidase 1 (CANT1), functions as a calcium-dependent nucleotidase with a preference for UDP. However, the potential clinical value of CANT1 in lung adenocarcinoma (LA) has not been fully clarified. Thus, we sought to identify its potential biological function and mechanism through bioinformatics analysis and in vitro experiments in LA. METHODS: In the present study, we comprehensively investigated the prognostic role of CANT1 in LA patients through bioinformatics analysis and in vitro experiments. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were utilized to analyze the expression of CANT1 in LA patients and their clinical-prognostic value. The immunohistochemistry staining was obtained from the Human Protein Atlas (HPA). A Cox regression model was used to evaluate prognostic factors. Gene ontology (GO) and Gene set enrichment analysis (GSEA) was performed to explore the potential regulatory mechanism of CANT1 in the development of LA. Moreover, we also examined the relationship between CANT1 expression and DNA methylation. Finally, we did in vitro experiments to evaluate the biological behavior and role of CANT1 in LA cells (LACs). RESULTS: Our study showed that the CANT1 expression was significantly elevated in the LA tissues compared with the normal lung tissues. Increased CANT1 expression was significantly associated with the TN stage. A univariate Cox analysis indicated that high CANT1 expression levels were correlated with poor overall survival (OS) in LA. Besides, CANT1 expression was independently associated with OS in multivariate analysis. GO and GSEA analysis showed the enrichment of mitotic nuclear division, DNA methylation, and DNA damage. Then we found that the high expression of CANT1 is positively correlated with hypomethylation. The methylation level was associated with prognosis in LA patients. Finally, in vitro experiments indicated that knockdown of CANT1 resulted in decreased cell proliferation, invasion, and G1 phase cell-cycle arrest in LACs. CONCLUSION: The present study suggested that CANT1 may serve as a potential prognosis biomarker in patients with LA. High CANT1 expression and promoter demethylation was associated with worse outcome. Finally, in vitro experiments verified the biological functions and behaviors of CANT1 in LA.


Assuntos
Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Nucleotidases/metabolismo , Idoso , Biomarcadores Tumorais/genética , Proliferação de Células/genética , Dano ao DNA/genética , Metilação de DNA/genética , Feminino , Ontologia Genética , Humanos , Masculino , Prognóstico
18.
Inorg Chem ; 61(13): 5215-5223, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35312318

RESUMO

Two borylaminoamidinatosilylenes (L)[(1,5-C8H14)B(Ar)N]Si (L = PhC(NtBu)2, Ar = 2,6-iPr2C6H3 (1)) and (L)[(1,5-C8H14)B(Ar')N]Si (Ar' = 2,4,6-Me3C6H2 (2)) have been prepared and utilized to investigate the reaction toward isocyanide. Reactions of 1 with the respective CN-2,6-Me2C6H3 and CNCy (Cy = cyclo-C6H11) produced compounds (L)Si(NAr)C(N-2,6-Me2C6H3)B(1,5-C8H14)(CN-2,6-Me2C6H3) (3) and (L)Si(NAr)C(NCy)C(NCy)B(1,5-C8H14)(CNCy) (4). Reactions of 2 with the respective CNCy and CN-2,6-Me2C6H3 yielded compounds cyclo-(L)SiN(Ar')C(NCy)B(1,5-C8H14)C(NCy) (5) and cyclo-(L)[(1,5-C8H14)B(Ar')N]SiC(CN-2,6-Me2C6H3)N(2,6-Me2C6H3)C(N-2,6-Me2C6H3) (6). Compounds 3-6 have different compositions and structures from each other. Density functional theory (DFT) calculations suggest initial formation of (L)[(1,5-C8H14)B(←:CN-2,6-Me2C6H3)(Ar)N]Si (A), (L)[(1,5-C8H14)B(←:CNCy)(Ar)N]Si (A'), (L)[(1,5-C8H14)B(←:CNCy)-(Ar')N]Si (A″), and (L)[(1,5-C8H14)B(←:CN-2,6-Me2C6H3)(Ar')N]Si (A‴) as the respective intermediates. The as-followed transition states TS, TS1', TS1″, and TS‴ all feature probable Si:→C(═N):→B bonding with different Gibbs energies of 7.24, 2.46, 3.86, and 6.59 kcal/mol, respectively, due to variation among the Ar, Ar', 2,6-Me2C6H3, and Cy groups in these species, and reacted in different ways.

19.
J Cell Physiol ; 236(2): 1391-1400, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32749682

RESUMO

The development of primordial germ cells (PGCs) undergoes epigenetic modifications. The study of histone methylation in regulating PGCs is beneficial to understand the development and differentiation mechanism of germ stem cells. Notably, it provides a theoretical basis for directed induction and mass acquisition in vitro. However, little is known about the regulation of PGC formation by histone methylation. Here, we found the high enrichment of H3K4me2 in the blastoderm, genital ridges, and testis. Chromatin immunoprecipitation sequencing was performed and the results revealed that genomic H3K4me2 is dynamic in embryonic stem cells, PGCs, and spermatogonial stem cells. This trend was consistent with the H3K4me2 enrichment in the gene promoter region. Additionally, narrow region triggered PGC-related genes (Bmp4, Wnt5a, and Tcf7l2) and signaling pathways (Wnt and transforming growth factor-ß). After knocking down histone methylase Mll2 in vitro and vivo, the level of H3K4me2 decreased, inhibiting Cvh and Blimp1 expression, then repressing the formation of PGCs. Taken together, our study revealed the whole genome map of H3K4me2 in the formation of PGCs, contributing to improve the epigenetic study in PGC formation and providing materials for bird gene editing and rescue of endangered birds.


Assuntos
Proteína Morfogenética Óssea 4/genética , Epigênese Genética/genética , Histona Metiltransferases/genética , Testículo/crescimento & desenvolvimento , Células-Tronco Germinativas Adultas/citologia , Células-Tronco Germinativas Adultas/metabolismo , Animais , Blastoderma/crescimento & desenvolvimento , Diferenciação Celular/genética , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Genitália/crescimento & desenvolvimento , Células Germinativas/crescimento & desenvolvimento , Masculino , Transdução de Sinais/genética , Testículo/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Fator de Crescimento Transformador beta/genética , Proteína Wnt-5a/genética
20.
J Am Chem Soc ; 143(5): 2212-2216, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33507736

RESUMO

The reaction of (LSi:)2 (1; L = PhC(NtBu)2) with 2 equiv of Me3SiC2C2SiMe3 resulted in the formation of (Me3SiC2)2(Me3Si)2C4Si2(L)2 (2). 2 exhibited a one-electron transfer when treated with 1 equiv of [Ph3C]+[B(C6F5)4]- to yield [(Me3SiC2)2(Me3Si)2C4Si2(L)2]·+[B(C6F5)4]- (3) and Ph3CCPh3, respectively. When compound 2 was treated with 2 equiv of AgOSO2CF3 a transfer of two electrons occurred to produce [(Me3SiC2)2(Me3Si)2C4Si2(L)2]2+·2[OSO2CF3]- (4) and elemental silver. The 1,4-disilabenzene 2 is disclosed of an open-shell singlet diradical character, and 3 and 4 are, respectively, the elusive stable radical cation and dication species of the 1,4-disilabenzene (2). Furthermore, 2 reacted with group 16 elements of O, S, and Se by oxidative addition to form (Me3SiC2)2(Me3Si)2C4Si2(L)2(µ-O2) (5) and (Me3SiC2)2(Me3Si)2C4Si2(L)2(µ-E) (E = S (6) and Se (7)), respectively.

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