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1.
Dalton Trans ; 53(4): 1698-1705, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38169009

RESUMO

Preparation of the high value-added chemical 2,5-dimethylfuran (2,5-DMF) from the biomass-derived platform molecule 5-hydroxymethylfurfural (HMF) is of great significance in the preparation of biofuels. Here, a bottom-up strategy was used to prepare a metal-organic framework (MOF) material with a two-dimensional nanosheet morphology, named CPM, in which an additive 2-methylimidazole was introduced into the hydrothermal process of Cu2+ ions and terephthalic acid. Subsequently, CPM-700 prepared by heat treatment under an inert atmosphere showed excellent catalytic performance in the reaction of HMF hydrodeoxygenation to 2,5-DMF. The materials before and after pyrogenation were characterized by PXRD, XPS, TEM, N2 adsorption and desorption and so on. It was confirmed that compared with the catalyst derived from the cubic MOF material self-assembled by Cu2+ and terephthalic acid, the morphology of 2D nanosheets was beneficial for the reaction of HMF to 2,5-DMF. Combined with the experimental data, the possible reaction path of 2,5-DMF preparation from HMF is that 2,5-dihydroxymethylfuran was formed by hydrogenation of the aldehyde group on the furan ring, and then 2,5-DMF was obtained by hydrogenolysis. This paper provides an effective route for 2D MOF-derived catalytic materials in the selective hydrogenation of HMF.

2.
Transl Androl Urol ; 12(1): 128-138, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36760876

RESUMO

Background: The amount of treatment-related neuroendocrine prostate cancer (t-NEPC) increases after hormonal therapy, especially novel androgen receptor pathway inhibitors (ARPIs). T-NEPC is considered a hormone refractory [androgen receptor (AR)-negative] subtype of prostate cancer. Although tumors are initially responsive to platinum-based chemotherapy, the drugs are only effective for a short time. Therefore, whether or not local treatment can prolong survival is of great concern. Case Description: In this case series, we discuss 4 t-NEPC cases who were treated with partial stereotactic ablative radiotherapy (P-SABR) for bulky tumors. P-SABR is a radiotherapy regimen that is used in a SABR boost [such as 6 Gy × 4 fractions (f), 8 Gy × 3 f] prior to conventional radiotherapy to enhance the tumor biological effective dose (BED) without increasing the dose to organs at risk. All patients achieved good local control after P-SABR. For patient 1, P-SABR was used for the prostate tumor. After radiotherapy, pathological complete remission (pCR) was achieved, and the prostate lesion remained stable thus far. As of this writing, the patient has been in remission for 3 years after initial t-NEPC diagnosis. Conclusions: We describe 4 cases and indicate that P-SABR is safe and effective in the treatment of a large prostate mass and may prolong the survival of these patients.

3.
Front Oncol ; 12: 860700, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35756638

RESUMO

Background: Plasma Epstein-Barr virus DNA (EBV-DNA) is a sensitive and specific biomarker for nasopharyngeal carcinoma (NPC). We investigated whether longitudinal monitoring of EBV-DNA could accurately detect clinical disease progression in NPC patients with bone-only metastases. Methods: In this retrospective study, a total of 105 patients with bone-only metastatic NPC who were treated with platinum-based first-line chemotherapy were enrolled. Undetectable EBV-DNA after first-line chemotherapy was defined as a biochemical complete response (BCR). The correlation of the EBV-DNA dynamic status with overall survival (OS) and progression-free survival (PFS) was determined by Cox regression. The correlation between non-normalized EBV-DNA period and PFS period was determined. Results: After a median follow-up time of 53.4 months [Interquartile range (IQR): 42.8-80.6], 64 patients had disease progression. Thirty-nine of 105 patients (37.1%) had a BCR at all follow-up time points, and none of these 39 patients had disease progression, corresponding to a negative predictive value (NPV) of 100%. Sixty-six patients had a detectable EBV-DNA during surveillance, with 64 diagnosed as disease progression at the last follow-up, for a positive predictive value (PPV) of 97.0%. Actuarial 3-year OS rates were 45.0% for patients with detectable EBV-DNA during posttreatment surveillance and 100% for patients with undetectable EBV-DNA. Lastly, median lead time between non-normalized EBV-DNA and clinically proven progression was 5.87 ± 0.67 months. Conclusions: Taken together, EBV-DNA provided predictive value for the bone-only metastatic NPC patients. The results should be validated in prospective randomized studies.

4.
ACS Appl Mater Interfaces ; 14(15): 17195-17207, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35384659

RESUMO

The efficient hydrogenation of biomass-derived levulinic acid (LA) to value-added γ-valerolactone (GVL) based on nonprecious metal catalysts under mild conditions is crucial challenge because of the intrinsic inactivity and instability of these catalysts. Herein, a series of highly active and stable carbon-encapsulated Co/ZnO@C-X (where X = 0.1, 0.3, 0.5, the molar ratios of Zn/(Co+Zn)) heterojunction catalysts were obtained by in situ pyrolysis of bimetal CoZn MOF-74. The optimal Co/ZnO@C-0.3 catalyst could achieve 100% conversion of LA and 98.35% selectivity to GVL under mild conditions (100 °C, 5 bar, 3 h), which outperformed most of the state-of-the-art catalysts reported so far. Detailed characterizations, experimental investigations, and theoretical calculations revealed that the interfacial interaction between Co and ZnO nanoparticles (NPs) could promote the dispersibility and air stability of the active Co0 for the activation of H2. Moreover, the strong Co-ZnO interaction also enhanced the Lewis acidity of the Co/ZnO interface, contributing to the adsorption of LA and the esterification of intermediates. The synergy between the hydrogenation sites and the Lewis acid sites at the Co/ZnO interface enabled the conversion of LA to GVL with high efficiency. In addition, benefiting from the Co-ZnO interfacial interaction as well as the unique carbon-encapsulated structure of the heterojunction catalyst, the recyclability was also greatly improved and the yield of GVL was nearly unchanged even after six cycles.

5.
Food Res Int ; 152: 110900, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35181076

RESUMO

Microbial ecosystems of fermented foods are largely interfered by human activities in myriad ways. The aim of this study was to illuminate the impacts of various starters and environmental variables on the fermentation process of Zhenjiang aromatic vinegar (ZAV), one of the four representative cereal vinegars in China. The effects of environmental variables (e.g., ethanol, total acidity, temperature) and starters (e.g., jiuqu, maiqu, seed pei) on the profiles of microbiome and metabolome (e.g., organic acids, amino acids and volatiles) during fermentation process of ZAV were analyzed. Amongst the four fermentation stages, acetic acid fermentation was the main stage for the accumulation of flavor substances, and subsequently, the contents of acids (mainly acetic, lactic and citric acids) and volatile metabolites (e.g., 2,3-butanedione, acetoin, etc.) continued to enrich in sealed fermentation stage. Principal coordinate analysis (PCoA) and analysis of similarities (ANOSIM) showed that the fungal and bacterial community structures of four fermentation stages were significantly different. As for bacterial community, the dominant OTUs with average relative abundance over 10% in at least one fermentation stage were assigned to the genera Acetilactobacillus, Acetobacter, Acinetobacter, Aeromonas, Lactobacillus, and Pseudomonas. The dominant fungal populations in each fermentation stage were obviously divergent, including Wickerhamomyces, Saccharomyces, Alternaria, Fusarium, etc. SourceTracker analysis demonstrated that jiuqu and seed pei provided microorganisms to initiate starch saccharification and acetic acid fermentation stages, respectively, and maiqu was mainly the donor of enzymes in alcohol fermentation. Spearman correlation coefficients revealed positive relationships between fungal community and various flavor metabolites, indicating the essential role of fungi in the flavor formation of ZAV. This study systematically reveals the effects of fermentation starters and environmental variables on vinegar production and deepens the understanding of the traditional production craft.


Assuntos
Acetobacter , Microbiota , Ácido Acético/metabolismo , Acetobacter/metabolismo , Bactérias , Fermentação , Humanos
6.
Light Sci Appl ; 11(1): 7, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34974532

RESUMO

Chaos in nonlinear dynamical systems is featured with irregular appearance and with high sensitivity to initial conditions. Near-infrared light chaos based on semiconductor lasers has been extensively studied and has enabled various applications. Here, we report a fully-developed hyperchaos in the mid-infrared regime, which is produced from interband cascade lasers subject to the external optical feedback. Lyapunov spectrum analysis demonstrates that the chaos exhibits three positive Lyapunov exponents. Particularly, the chaotic signal covers a broad frequency range up to the GHz level, which is two to three orders of magnitude broader than existed mid-infrared chaos solutions. The interband cascade lasers produce either periodic oscillations or low-frequency fluctuations before bifurcating to hyperchaos. This hyperchaos source is valuable for developing long-reach secure optical communication links and remote chaotic Lidar systems, taking advantage of the high-transmission windows of the atmosphere in the mid-infrared regime.

7.
Inorg Chem ; 60(24): 19328-19335, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34865466

RESUMO

Ethylene (C2H4) is one of the most significant substances in the petrochemical industry; however, the capture of acetylene (C2H2) in about 1% from C2H2/C2H4 mixtures is a difficult task because of the similarity of their physical properties. With the aggravation of the energy crisis, using metal-organic framework (MOF) materials to purify C2H4 through adsorptive separation is a promising way to save energy and reduce emission. Pore-space partition (PSP) with the aim of enhancing the density of the binding sites and the strength of the host-guest interactions is an effective means to promote a solution for the challenging gas separation problems. Herein, we report a new embedding metal-carboxylate chain-induced topology upgrade strategy within a MOF to realize PSP and separation of C2H2/C2H4 mixtures. As a proof of concept, we construct a microporous MOF (NUM-12) utilizing the in situ insertion of cobalt terephthalic chains into a pretargeted ant-type framework during synthesis. Because of the attainment of an elaborately tuned aperture size and a specific pore environment through this strategy, NUM-12a (activated NUM-12) not only has a remarkable gas sorption capacity and strong interactions for C2H2 but also possesses an excellent purification performance for C2H2/C2H4 mixtures. Both experiments and simulation calculations clearly reveal that NUM-12 is a promising candidate for the separation of C2H2/C2H4, proving the feasibility of this new strategy for developing newly fashioned MOFs with adjustable structure and performance.

8.
ACS Appl Mater Interfaces ; 13(10): 12169-12180, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33682409

RESUMO

Carbon-encapsulated metal-organic framework (MOF) composite is one kind of emerging new catalyst with high efficiency and has gained much attention. However, for this kind of composite catalyst, the key to improving its catalytic activity and durability is to realize the effective dispersion of MOF nanoparticles (NPs) and enhance the interaction between MOF NPs and the carbon matrix, which remain a significant challenge. Herein, ultrafine MOF NPs within multichamber carbon spheres (MOF@MCCS), for the first time, have been rationally synthesized by a two-step double-solvent strategy for high-performance catalysts. The precise loading of guest MOFs can be achieved by adjusting the multichamber structure and calcination extent of the multichamber polymer (MCP), and the particle size of MOFs can be as low as 13.2 nm. Due to the formation of abundant carbon defects in the pyrolysis process of MCPs, the special structure and synergistic effect make the material exhibit higher catalytic activity and durability. More importantly, this method is universal and can be extended to different MOF systems. The two-step double-solvent strategy not only prepares a unique structure of MOF@MCCS-type host-guest-encapsulated catalysts but also provides a new idea for the design of high-efficiency catalysts with better performance and higher durability.

9.
Cancer Control ; 28: 1073274821997426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33626920

RESUMO

PURPOSE: Although breast conservation surgery(BCS) followed by adjuvant radiotherapy is now the mainstream treatment method for breast ductal carcinoma in situ(DCIS), mastectomy is still performed in some patients who refuse to undergo radiation. However, the most effective treatment method for these patients is still unknown. In the current study, we aimed to compare the survival rates between mastectomy and BCS plus adjuvant radiotherapy in patients with DCIS. MATERIALS AND METHODS: We performed a retrospective study of 333 patients with DCIS from May 2004 to December 2016. There were 209 patents who were treated with BCS and adjuvant radiotherapy, while the remaining of 124 patients underwent mastectomy. The disease-free survival (DFS) and local recurrence-free survival(LRFS) rates were compared between the 2 treatment groups. Cox proportional hazards regression was performed to explore factors associated with DFS and LRFS. RESULTS: The 10-year local recurrence(LR) rates in the mastectomy and BCS plus adjuvant radiotherapy groups were 2.6% and 7.5%, respectively. There was no difference in the LR rate between the 2 groups. Furthermore the DFS rate was also similar between the mastectomy and BCS plus adjuvant radiotherapy groups. Based on the multivariable analysis, age and tumor grade were significantly correlated with the LRFS and DFS rates. In the subgroup analysis based on the factors of age and tumor grade, patients with a tumor grade of III who underwent mastectomy had better LRFS and DFS rates compared to those who received BCS plus radiotherapy. CONCLUSION: In patients with DCIS, the long-term efficacy was similar between mastectomy and BCS followed by adjuvant radiotherapy. However, in the subgroup of patients with grade III tumors, mastectomy seems to offer a better LRFS and DFS than BCS plus radiotherapy.


Assuntos
Carcinoma Ductal de Mama/terapia , Carcinoma Ductal de Mama/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos
10.
Cancer Manag Res ; 13: 1325-1332, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603478

RESUMO

PURPOSE: The optimum timing of adjuvant radiotherapy for breast cancer patients who had undergone surgery remains unclear. The present study aimed to identify the clinical factors which could assist the selecting of time interval (TI) between surgery and adjuvant radiotherapy in luminal breast cancer with lymph node metastasis. PATIENTS AND METHODS: This retrospective study included 1054 luminal breast cancer patients with lymph node metastasis, diagnosed between May 2004 and December 2014, and treated with surgery followed by adjuvant therapy. Overall survival (OS) and disease-free survival (DFS) were compared between patients in the short and long TI groups. Multivariate analysis was performed to examine clinical factors associated with DFS. Subgroups analysis was further performed based on the significant predictors of DFS to explore the association of TI and tumor prognosis. RESULTS: For the whole group of patients, there was no difference in OS and DFS between patients with long and short TI. Multivariate analysis showed that age, N stage and tumor size were significant predictors of DFS. Subgroup analysis demonstrated that neither age nor N stage were informative in TI selection; in contrast, in patients with large tumors, a short TI was associated with better DFS than a long TI. In patients with small tumors, there was no significant association between TI and tumor prognosis. In the multivariable analysis, TI was independent predictor of DFS and local recurrence-free survival in patients with large tumors. CONCLUSION: Large tumor size is an indicator for the timely administration of adjuvant radiotherapy in luminal breast cancer with positive lymph node.

11.
Laryngoscope ; 131(2): E489-E499, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33135805

RESUMO

OBJECTIVES: To characterize sarcomatoid cell carcinoma (SaC) in head and neck, explore the value of radiotherapy (RT) and chemotherapy, and build a nomogram to predict the prognosis. STUDY DESIGN: Retrospective cohort study. METHODS: In total, 559 patients diagnosed with head and neck SaC from 2004 to 2015 were included from the Surveillance, Epidemiology, and End Results program. All the cases were divided into training (N = 313) and validation (N = 246) cohorts according to the year of diagnosis. The cases were analyzed on the age, site, sex, race, T stage, N stage, M stage, surgery, RT, and chemotherapy. Cancer-specific survival (CSS) and overall survival (OS) were compared among disease-related categories. The parameters significantly correlated with CSS were used to construct a nomogram. RESULTS: The multivariate analysis showed that age, T stage, N stage, and M stage were significantly correlated with CSS and OS. Overall, RT was correlated with improved CSS for Stage T3-4 and Stage N1-3. The subgroup analysis showed that RT was correlated with CSS in the Stage N1-3 patients after surgery while chemotherapy indicated an improved survival for Stage T3-4 and N1-3 patients without surgery. The prognostic nomogram was constructed and had a powerful discriminatory ability with the C-index of CSS: 0.711. CONCLUSION: Late-stage head and neck SaC patients unfit for surgery need comprehensive treatment based on chemotherapy, and patients with node metastasis require adjuvant RT after surgery. Generally, RT might improve the survival of late-stage patients. A reliable and powerful nomogram was established that can provide an individual prediction of CSS for head and neck SaC. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:E489-E499, 2021.


Assuntos
Neoplasias de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Idoso , Terapia Combinada/mortalidade , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Nomogramas , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Análise de Sobrevida
12.
Cancer Manag Res ; 12: 9211-9219, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061612

RESUMO

BACKGROUND: Due to the low rate of regional recurrence (RR) in early-stage breast cancer with pT1-2 and negative sentinel lymph node biopsy (SLNB), no regional therapy is suggested for them. However, whether there is a subset of patients who were with high risk of regional failure and may benefit from regional treatment is still unknown. The current study was designed to identify the patients with high risk of RR, thereby providing clues for enhanced regional therapy. METHODS: We analyzed a total of 1124 breast cancer patients with pT1-2N0 from May 2004 to Dec 2014. All the patients were treated with breast-conservation surgery (BCS) and adjuvant whole-breast radiotherapy. The regional recurrence-free survival (RRFS), local regional recurrence-free survival (LRRFS), disease-free survival (DFS) and overall survival (OS) were assessed by using the Kaplan-Meier method. Cox proportional hazards regression was performed to detect factors in predicting the RRFS. RESULTS: In multivariable analysis, both T stage and molecular type were significant predictors of RRFS. Patients with T2 stage had a lower RRFS than those with T1stage. Triple-negative patients were more likely to suffer regional failure than the patients with other molecular types. The two predictors were then employed to divide all the patients into three groups based on the risk level of RR. Patients with both T2 and triple-negative molecular type had the lower RRFS, LRRFS, DFS and OS than the patients with one or no risk factor. CONCLUSION: For early-stage breast cancer patients with negative SLNB, those who were with both T2 stage and triple-negative molecular type had a high rate of RR and enhance regional therapy may be needed for them.

13.
Cancer Biol Ther ; 21(10): 972-982, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33047994

RESUMO

Cervical cancer (CC) is the second most common malignancy in women worldwide. The mechanism underlying CC development remains unclear. Recently, Circular RNAs (circRNAs)have attracted attention because of its role in tumorigenesis. To investigate circRNAsin CC, RNA sequencing was employed to characterize circRNA expression profile between CC tissues and matched adjacent normal tissues. The expression of hsa_circ_0003204 was examined in CC tissues and cell lines by real-time PCR. Migration assay and invasion assay were used to verify the effect of hsa_circ_0003204 on migration and invasion ability in CC cell lines. Tumor formation assay in nude mice was used to analyze the effect of hsa_circ_0003204 on the tumorigenicity of CC cell lines in vitro. Western blotting analyzes were performed to investigate the role of hsa_circ_0003204 in the regulation of MAPK signaling activation. We found that circRNA hsa_circ_0003204 was significantly upregulated in CC tissues. The function and potential molecular mechanisms of hsa_circ_0003204 were also investigated in vitro and in vivo. Hsa_circ_0003204 knockdown reduced cell growth, migration, and invasion but promoted cells apoptosis. However, the over-expression of hsa_circ_0003204 had the opposite effect. The MAPK pathway was different in hsa_circ_0003204 over-expression or down-expression cells, compared to parental cells. In addition, over-expression of hsa_circ_0003204 significantly increased tumor volume and tumor weight in vivo.Taken together, results indicated hsa_circ_0003204 may serve as a potential therapeutic target for patients with CC.


Assuntos
Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Neoplasias do Colo do Útero/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Humanos , Invasividade Neoplásica , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
14.
CNS Neurosci Ther ; 26(12): 1288-1302, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32790044

RESUMO

BACKGROUND: Specific highly polarized aquaporin-4 (AQP4) expression is reported to play a crucial role in blood-brain barrier (BBB) integrity and brain water transport balance. The upregulation of polymerase δ-interacting protein 2 (Poldip2) was involved in aggravating BBB disruption following ischemic stroke. This study aimed to investigate whether Poldip2-mediated BBB disruption and cerebral edema formation in mouse bacterial meningitis (BM) model occur via induction of AQP4 polarity loss. METHODS AND RESULTS: Mouse BM model was induced by injecting mice with group B hemolytic streptococci via posterior cistern. Recombinant human Poldip2 (rh-Poldip2) was administered intranasally at 1 hour after BM induction. Small interfering ribonucleic acid (siRNA) targeting Poldip2 was administered by intracerebroventricular (i.c.v) injection at 48 hours before BM induction. A specific inhibitor of matrix metalloproteinases (MMPs), UK383367, was administered intravenously at 0.5 hour before BM induction. Western blotting, immunofluorescence staining, quantitative real-time PCR, neurobehavioral test, brain water content test, Evans blue (EB) permeability assay, transmission electron microscopy (TEM), and gelatin zymography were carried out. The results showed that Poldip2 was upregulated and AQP4 polarity was lost in mouse BM model. Both Poldip2 siRNA and UK383367 improved neurobehavioral outcomes, alleviated brain edema, preserved the integrity of BBB, and relieved the loss of AQP4 polarity in BM model. Rh-Poldip2 upregulated the expression of MMPs and glial fibrillary acidic protein (GFAP) and downregulated the expression of ß-dystroglycan (ß-DG), zonula occludens-1 (ZO-1), occludin, and claudin-5; whereas Poldip2 siRNA downregulated the expression of MMPs and GFAP, and upregulated ß-DG, ZO-1, occludin, and claudin-5. Similarly, UK383367 downregulated the expression of GFAP and upregulated the expression of ß-DG, ZO-1, occludin, and claudin-5. CONCLUSION: Poldip2 inhibition alleviated brain edema and preserved the integrity of BBB partially by relieving the loss of AQP4 polarity via MMPs/ß-DG pathway.


Assuntos
Aquaporina 4/biossíntese , Barreira Hematoencefálica/metabolismo , Edema Encefálico/metabolismo , Modelos Animais de Doenças , Meningites Bacterianas/metabolismo , Proteínas Mitocondriais/biossíntese , Proteínas Nucleares/biossíntese , Administração Intranasal , Animais , Aquaporina 4/genética , Barreira Hematoencefálica/patologia , Edema Encefálico/genética , Edema Encefálico/patologia , Humanos , Masculino , Meningites Bacterianas/genética , Meningites Bacterianas/patologia , Camundongos , Proteínas Mitocondriais/deficiência , Proteínas Mitocondriais/genética , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética
15.
Chem Commun (Camb) ; 56(10): 1553-1556, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31930267

RESUMO

An enantioselective (3+2) cycloaddition of enals and cyclic N-sulfonyl trifluoromethyl ketimines via N-heterocyclic carbene-catalyzed homoenolate addition is described. This reaction can efficiently construct fused N-heterocycle γ-lactams bearing two adjacent chiral centers with >20 : 1 dr and 94-99% ee, with one chiral center as a trifluoromethylated α-tetrasubstituted carbon stereocenter.

16.
Genes Dis ; 6(4): 398-406, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31832520

RESUMO

This study aimed to assess the role of microRNAs (miRNAs) in regulating monocarboxylate transporter-1 (MCT1) expression in rat brain after permanent focal cerebral ischemia to identify a new target for early treatment of cerebral ischemia. Focal cerebral ischemia was induced by permanent middle cerebral artery occlusion (pMCAO) in rats. Morphology and protein expression levels of MCT1 were assessed by immunofluorescence and Western blotting. Using bioinformatics and double luciferase reporter assays, rno-miR-124-3p was selected as a direct target for rat MCT1. Expression of rno-miR-124-3p after pMCAO was detected. Then, rats were treated with rno-miR-124-3p agomir via lateral ventricle injection, and after 6 h or 24 h ischemia, rno-miR-124-3p expression and gene and protein expression of MCT-1 were detected by qRT-PCR and Western blotting. Brain infarction was identified by 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. Results showed that pMCAO induced brain infarction and increased the expression of MCT1. The levels of rno-miR-124-3p after pMCAO were in contrast to those of MCT1 protein in ischemic region, while declined after 3, 6 and 12 h of pMCAO in ischemic penumbra. After administration of rno-miR-124-3p agomir, MCT1 mRNA and protein levels were increased after 6 h of pMCAO, while decreased after 24 h of pMCAO. Meanwhile, rno-miR-124-3p levels increased after both times. TTC staining showed treatment with rno-miR-124-3p agomir reduced brain infarction. The role of rno-miR-124-3p in regulating MCT1 was as a positive regulator after 6 h of pMCAO, while a negative regulator after 24 h of pMCAO, however, both activities had protective effects against cerebral ischemia.

17.
Brain Res ; 1721: 146347, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31348910

RESUMO

We previously reported that aquaporin 4 (AQP4) played a critical role in formation of brain edema and the altered expression of dystroglycan (DG) could relate with AQP4 expression after traumatic brain injury (TBI). However the mechanisms of this process remain unclear. DG was showed could act as a scaffold involved in adhesion-mediated signaling in ERK/MAPK pathway. We hypothesize that after scratch, extracellular α-DG and transmembrane ß-DG may act as the scaffold in scratch mechanical force activating ERK pathway which may regulate the expression of AQP4. Use ERK inhibitor and activator to confirm whether the expression of AQP4 is regulated by the activation of ERK pathway in scratched astrocytes. Use DG siRNA to confirm whether DG takes part in the process that the extracellular signal transduces into cell and activates the ERK pathway. The significant increase of AQP4 and DG expression induced by scratch could be abolished by blocking ERK signaling and enhanced by activating ERK signaling. Blockade of DG by siRNA led to no obvious effect of scratched-injury on the ERK signaling pathway. It demonstrated that DG may act as the scaffold in scratch mechanical force activating ERK pathway which can regulate the expression of AQP4 in astrocytes after scratch.


Assuntos
Aquaporina 4/metabolismo , Astrócitos/fisiologia , Distroglicanas/metabolismo , Animais , Aquaporina 4/fisiologia , Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Edema Encefálico/metabolismo , Células Cultivadas , Distroglicanas/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
18.
Cancer Manag Res ; 11: 4815-4823, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213903

RESUMO

Background: Whether concurrent chemotherapy could bring about better oncological outcomes in elderly patients receiving definitive radiotherapy is still unknown. So, the purpose of this study was to find out whether it is essential for elderly patients to undergo concurrent chemotherapy. Methods: We performed a retrospective study of 246 elderly cervical cancer patients who were treated with definitive radiotherapy or chemo-radiation between August 2004 and August 2015. All patients were divided into two groups according to whether they were receiving concurrent chemotherapy or not. Overall survival (OS) and disease-free survival (DFS) were compared between the two groups. Recurrence patterns were also analyzed. Multivariate analysis was performed to explore clinical factors significantly associated with DFS, local recurrence-free survival, and distant metastasis-free survival (DMFS). Results: The 5-year OS in the radiotherapy and chemo-radiation groups were 72.89% and 82.25%, respectively. A significant difference was found between the two groups (P=0.016). The 5-year DFS in the radiotherapy and chemo-radiaton groups were 58.19% and 75.52%, respectively, also with a significant difference between the two groups (P=0.028). Further subgroup analysis showed that in patients with negative lymph nodes, there were no differences in both OS and DFS between patients who did and did not receive concurrent chemotherapy. However, in patients with positive lymph nodes, patients who received concurrent chemotherapy acquired better OS and DFS than those who did not. Multivariable analysis showed that concurrent chemotherapy was an independent predictor of DFS and DMFS. Conclusion: Concurrent chemotherapy could improve oncological outcomes in elderly cervical cancer patients with positive lymph nodes, but not in those with negative lymph nodes.

20.
World J Gastroenterol ; 25(1): 138-150, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30643364

RESUMO

AIM: To evaluate the clinical properties of three subpopulations of circulating tumor cells (CTCs) undergoing epithelial-mesenchymal transition (EMT) in pancreatic ductal adenocarcinoma (PDAC) patients. METHODS: We identified CTCs for expression of the epithelial cell marker cytokeratin or epithelial cell adhesion molecule (EpCAM) (E-CTC), the mesenchymal cell markers vimentin and twist (M-CTC), or both (E/M-CTC) using the CanPatrol system. Between July 2014 and July 2016, 107 patients with PDAC were enrolled for CTC evaluation. CTC enumeration and classification were correlated with patient clinicopathological features and outcomes. RESULTS: CTCs were detected in 78.5% of PDAC patients. The number of total CTCs ranged from 0 to 26 across all 107 patients, with a median value of six. CTC status correlated with lymph node metastasis, TNM stage, distant metastasis, blood lymphocyte counts, and neutrophil-to-lymphocyte ratio (NLR). Kaplan-Meier survival analysis showed that patients with ≥ 6 total CTCs had significantly decreased overall survival and progression-free survival compared with patients with < 6 total CTCs. The presence of M-CTCs was positively correlated with TNM stage (P < 0.01) and distant metastasis (P < 0.01). Additionally, lymphocyte counts and NLR in patients without CTCs were significantly different from those in patients testing positive for each CTC subpopulation (P < 0.01). CONCLUSION: Classifying CTCs by EMT markers helps to identify the more aggressive CTC subpopulations and provides useful evidence for determining a suitable clinical approach.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Ductal Pancreático/patologia , Transição Epitelial-Mesenquimal , Células Neoplásicas Circulantes/patologia , Neoplasias Pancreáticas/patologia , Idoso , Carcinoma Ductal Pancreático/sangue , Carcinoma Ductal Pancreático/mortalidade , Molécula de Adesão da Célula Epitelial/análise , Feminino , Humanos , Estimativa de Kaplan-Meier , Biópsia Líquida/métodos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/análise , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/mortalidade , Prognóstico , Proteína 1 Relacionada a Twist/análise , Vimentina/análise
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