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1.
Org Biomol Chem ; 22(21): 4249-4253, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38717449

RESUMO

A Cu2O-catalyzed cascade phosphinylation/cyclization reaction of 2'-aminochalcones and diphenylphosphine oxides to produce hemi-indigo derivatives has been developed. This strategy facilitates the sequential formation of a C-P bonds and a C-N bond in a single reaction step. Notably, the approach features one-pot operation, an earth-abundant copper catalyst, readily available starting materials, a broad substrate scope and high compatibility with functional groups, providing 33 compounds in acceptable yields.

2.
J Org Chem ; 88(1): 143-153, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36563294

RESUMO

An efficient method of Rh(III)-catalyzed coupling reaction between 2-arylquinazolinones and gem-difluorostyrenes has been developed. In this work, two diverse structures of monofluoroalkenes and isoindolo[1,2-b]quinazolin-10(12H)-one derivatives were respectively synthesized by controlling the amount of additives (Ca(OH)2 and AgNTf2) to achieve controlled stepwise breaking of the C-F bonds of gem-difluorostyrenes. This reaction has the characteristics of a wide range of substrates and good functional group tolerance. Meanwhile, several control experiments were conducted and a plausible mechanism was proposed.

3.
Org Biomol Chem ; 21(37): 7611-7615, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37681741

RESUMO

Pyrazoles as an important class of heterocyclic compounds, are widely found in pharmaceuticals and bioactive natural products. Herein we report a [3 + 2] cycloaddition reaction for the synthesis of a series of pyrazoles, with the yield up to 77%. This approach exhibits many notable features, such as convenient operating conditions, excellent functional group compatibility and readily accessible raw materials, providing an alternative route for the construction of pyrazole derivatives.

4.
Org Biomol Chem ; 20(4): 887-894, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35018957

RESUMO

A highly efficient Rh(III)-catalyzed cascade C-H activation/annulation of sulfoximines with iodonium ylides under metal-oxidant-free conditions has been reported. The fused cyclohexanone-1,2-benzothiazine scaffold is readily achieved with a one-pot process in this reaction. This protocol exhibits good functional group tolerance and moderate to excellent yields. Additionally, the olefination of the target product illustrates the promising usefulness of this strategy.

5.
World J Surg Oncol ; 20(1): 296, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104818

RESUMO

BACKGROUND: The safe distance between the intraoperative resection line and the visible margin of the distal rectal tumor after preoperative radiotherapy is unclear. We aimed to investigate the furthest tumor intramural spread distance in fresh tissue to determine a safe distal intraoperative resection margin length. METHODS: Twenty rectal cancer specimens were collected after preoperative radiotherapy. Tumor intramural spread distances were defined as the distance between the tumor's visible and microscopic margins. Visible tumor margins in fresh specimens were identified during the operation and were labeled with 5 - 0 sutures under the naked eye at the distal 5, 6, and 7 o'clock directions of visible margins immediately after removal of the tumor. After fixation with formalin, the sutures were injected with nanocarbon particles. Longitudinal tissues were collected along three labels and stained with hematoxylin and eosin. The spread distance after formalin fixation was measured between the furthest intramural spread of tumor cells and the nanocarbon under a microscope. A positive intramural spread distance indicated that the furthest tumor cell was distal to the nanocarbon, and a negative value indicated that the tumor cell was proximal to the nanocarbon. The tumor intramural spread distance in fresh tissue during the operation was 1.75 times the tumor intramural spread distance after formalin fixation according to the literature. RESULTS: At the distal 5, 6, and 7 o'clock direction, seven (35%), five (25%), and six (30%) patients, respectively, had distal tumor cell intramural spread distance > 0 mm. The mean and 95% confidence interval of tumor cell intramural spread distance in fresh tissue during operation was - 0.3 (95%CI - 4.0 ~ 3.4) mm, - 0.9 (95%CI - 3.4 ~ 1.7) mm, and - 0.4 (95%CI - 3.5 ~ 2.8) mm, respectively. The maximal intraoperative intramural spread distances in fresh tissue were 8.8, 7, and 7 mm, respectively. CONCLUSIONS: The intraoperative distance between the distal resection line and the visible margin of the rectal tumor after radiotherapy should not be less than 1 cm to ensure oncological safety.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Formaldeído , Humanos , Margens de Excisão , Neoplasias Retais/patologia , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia
6.
Cancer Cell Int ; 21(1): 501, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535128

RESUMO

BACKGROUND: Recent reports suggest that the long non-coding RNA LBX2 antisense RNA 1 (LBX2-AS1) acts as an important regulator in cancer progression, but its significance in colorectal cancer (CRC) remains undetermined. METHODS: LBX2-AS1 expression levels in CRC were determined from the GEPIA database and CRC tissues to investigate clinical relevance. meRIP-PCR assays investigated the molecular mechanisms underlying the function of m6A in LBX2-AS1. Loss of function experiments was used to define the role of LBX2-AS1 in the progression of CRC. The ceRNA function of LBX2-AS1 was evaluated by RNA immunoprecipitation. In vitro and PDX models were used to determine if LBX2-AS1 promotes 5-fluorouracil resistance. RESULTS: Data from the TCGA and our institutional patient cohorts established that LBX2-AS1 levels were significantly upregulated in most CRC tissues relative to normal adjacent colon tissues. Moreover, LBX2-AS1 levels were positively correlated with aggressive disease characteristics, constituting an independent prognostic indicator of overall patient survival. Mechanistic investigations suggested that the increased LBX2-AS1 in CRC was mediated by METTL3-dependent m6A methylation. In vitro experiments indicated that knockdown of LBX2-AS1 inhibited CRC proliferation, migration and invasion with this phenotype linked to LBX2-AS1-mediated regulation of AKT1, acting as a ceRNA to sponge miR-422a. Ex vivo analysis of patient-derived CRC xenografts showed that low LBX2-AS1 expression cases exhibited 5-FU responsiveness and clinical investigations confirmed that low LBX2-AS1 expression was associated with improved clinical benefits from 5-FU therapy. CONCLUSIONS: Together these results suggest that LBX2-AS1 may serve as a therapeutic target and predictor of 5-FU benefit in CRC patients.

7.
Mol Carcinog ; 58(10): 1897-1907, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31313392

RESUMO

The mechanism of hepatocellular carcinoma (HCC) metastasis remains poorly understood. Tropomodulin 3 (TMOD3) is a member of the pointed end capping protein family that contributes to invasion and metastasis in several types of malignancies. It has been found to be crucial for the membranous skeleton and embryonic development, although, its role in HCC progression remains largely unclear. We observed increased levels of Tmod3 in HCCs, especially in extrahepatic metastasis. High Tmod3 expression correlated with aggressive carcinoma and poor patient with HCC survival. Loss-of-function studies conducted by us determined Tmod3 as an oncogene that promoted HCC growth and metastasis. Mechanistically, Tmod3 increases transcription of matrix metalloproteinase-2, -7, and -9 which required PI3K-AKT. Interaction between Tmod3 and epidermal growth factor receptor (EGFR) that supports the activation of EGFR phosphorylation, is essential for signaling activation of PI3K-AKT viral oncogene homolog. These findings reveal that Tmod3 enhances aggressive behavior of HCC both in vitro and in vivo by interacting with EFGR and by activating the PI3K-AKT signaling pathway.


Assuntos
Carcinoma Hepatocelular/genética , Proliferação de Células/genética , Neoplasias Hepáticas/genética , Tropomodulina/genética , Animais , Carcinoma Hepatocelular/patologia , Progressão da Doença , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/genética , Receptores ErbB/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica , Proteína Oncogênica v-akt/genética , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais/genética
8.
Org Biomol Chem ; 17(43): 9479-9488, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31651023

RESUMO

A convenient and straightforward three-component transformation of quinoline N-oxides, sodium metabisulfite and aryldiazonium tetrafluoroborates has been developed, providing the target products in moderate to good yields. Compared with previous studies, the present methodology avoids the use of transition-metal catalysts and excess oxidants, providing a simple and practical alternative approach for the construction of 2-sulfonylquinolines. Control experiments indicate that a dual radical coupling process is responsible for this reaction.

10.
Int J Colorectal Dis ; 32(10): 1431-1437, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28766076

RESUMO

PURPOSE: The purpose of this study was to evaluate the risk factors for anastomotic leakage (AL) after anterior resection for middle and low rectal cancer in order to help surgeons to decide which patients could benefit from a diverting stoma. METHODS: Data on 319 patients having a middle and low rectal cancer resection with anastomosis between May 2011 and October 2015 from two hospitals were included in the study. The analysis included the following variables: patient-related variables (gender, age, diabetes mellitus, ASA score, preoperative radiochemotherapy, body mass index, blood hemoglobin, and serum albumin level), tumor-related variables (K-ras status, distance of tumor from the anal verge, histopathologic grade, pathological T stage, pathological N stage, pathological M stage, TNM stage, and tumor size), and surgery-related variables (laparoscopic or open surgery, blood loss, and operative time). Univariate and multivariate regression analysis were carried out to identify risk factors for AL. RESULTS: The AL rate was 11.91% (38/319). Male (OR 2.898, 95% CI 1.265-6.637, p = 0.012), diabetes mellitus (OR 2.482, 95% CI 1.004-6.134, p = 0.049), K-ras mutation (OR 2.544, 95% CI 1.210-5.348, p = 0.014), distance of tumor from the anal verge (OR 3.445, 95% CI 1.631-7.279, p = 0.001), and preoperative radiochemotherapy (OR 2.790, 95% CI 1.056-7.372, p = 0.039) were independent risk factors of AL. One (2.63%) in 38 patients with AL presented with no risk factor of AL, 6 (15.8%) in 38 patients with 1 risk factor, 16 (42.1%) in 38 patients with 2 risk factors, 9 (23.7%) in 38 patients with 3 risk factors, and 6 (15.7%) in 38 patients with 4 risk factors. No patient with 5 risk factors in our study. AL rate increased with the elevated number of risk factors clustering in individuals. CONCLUSIONS: K-ras mutation is first reported to be an independent risk factor for AL after sphincter-preserving surgery without diverting stoma. A diverting stoma should be performed in sphincter-preserving surgery for middle and low rectal cancer patients with 2 or more risk factors identified in this analysis.


Assuntos
Fístula Anastomótica/epidemiologia , Neoplasias Retais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Quimiorradioterapia Adjuvante , Complicações do Diabetes/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Terapia Neoadjuvante , Estomia , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Retais/complicações , Neoplasias Retais/genética , Reoperação , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
11.
Int J Colorectal Dis ; 31(8): 1427-30, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27278476

RESUMO

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) in addition to the curative surgery has been the first of treatment for local advanced rectal cancer because of its benefits in local recurrence and sphincter-saving. However, its side effects on anorectal function have been recognized. The histopathological changes on internal anal sphincter (IAS) have been reported, but ultrastructure changes of external anal sphincter (EAS) are unknown. The aim of this study is to detect the alterations on the gross morphology of IAS and ultrastructure of EAS after nCRT. METHODS: We collected 34 anal canal specimens of patients undergoing abdominoperineal resection (APR) prospectively. The length and thickness of IAS were measured with vernier caliper. The EAS was dissected for observation with transmission electron microscope (TEM). RESULTS: Ten patients received nCRT (nCRT group) before surgery and 24 underwent APR directly (control group). The length and thickness of IAS in nCRT group were 22.68 ± 3.56 and 5.39 ± 0.74 mm, respectively. These parameters were 21.28 ± 3.62 and 5.35 ± 1.12 mm in control group, respectively. There were no significant differences in the length and thickness of IAS between the two groups (P>0.05). In nCRT group, the sarcomere and myofibril were arranged disorderly and parts of them that were filled with collagenous fiber, triads, and mitochondria were destroyed severely and the glycogenosome also distributed disorderly. Such alterations of EAS did not occur in control group. CONCLUSIONS: The nCRT cannot change the gross morphology of IAS, while it induces serious damages to the ultrastructures of EAS which may adversely affect the anorectal function.


Assuntos
Canal Anal/efeitos da radiação , Canal Anal/ultraestrutura , Quimiorradioterapia/efeitos adversos , Terapia Neoadjuvante/efeitos adversos , Canal Anal/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Surg Endosc ; 28(8): 2309-16, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24566747

RESUMO

BACKGROUND: Colonoscopic perforation (CP) has a low incidence rate. However, with the extensive use of colonoscopy, even low incidence rates should be evaluated to identify and address risks. Information on CP is quite limited in China. OBJECTIVE: Our study aimed to determine the frequency of CP in colonoscopies performed by surgeons at a large teaching hospital in China over a 12-year period. METHODS: A retrospective review of medical records was performed for all patients who had CPs from 1 January 2000 to 31 December 2012. Iatrogenic perforations were identified mainly by abdominal X-ray or computed tomography scan. Follow-up information of adverse events post-colonoscopy was identified from the colorectal surgery database of our hospital. Patients' demographic data, colonoscopy procedure information, location of perforation, treatment, and outcome were recorded. RESULTS: A total of 110,785 diagnostic and therapeutic colonoscopy procedures were performed (86,800 diagnostic cases and 23,985 therapeutic cases) within the 12-year study period. A total of 14 incidents (0.012%) of CP were reported (seven males and seven females), of which nine cases occurred during diagnostic colonoscopy (0.01%) and five after therapeutic colonoscopy (three polypectomy cases, one endoscopic mucosal resection, and one endoscopic mucosal dissection). Mean patient age was 67.14 years. One case of CP (7.14%) after colonoscopy polypectomy was treated using curative colonoscopy endoclips. Other patients underwent operations: six cases (46.15%) of primary repair, four cases (28.57%) of resection with anastomosis, and two cases (15.38%) of resection without anastomosis. No obvious perforation was found in one patient (7.69%). Surgeons attempted to treat one case laparoscopically but eventually resorted to open surgery. The postoperative course was uncomplicated in eight cases (57.14%) and complicated in six cases (42.86%) but without mortality. CONCLUSION: CP is a serious but rare complication of colonoscopy. A perforation risk of 0.012% was found in our study. The optimal management of CP remains controversial. Treatment for CP should be individualized according to the patient's condition, related devices, and surgical skills of endoscopists or surgeons. Selective measures such as colonoscopy without intravenous sedation and decrease of loop formation can effectively reduce rates of perforation.


Assuntos
Colonoscopia/efeitos adversos , Perfuração Intestinal/epidemiologia , Perfuração Intestinal/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , China/epidemiologia , Colo/cirurgia , Pólipos do Colo/cirurgia , Feminino , Hospitais de Ensino , Humanos , Mucosa Intestinal/cirurgia , Perfuração Intestinal/cirurgia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos
13.
Chem Asian J ; 19(1): e202300901, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37964673

RESUMO

Transition-mental-free multi-component hydroxysulfenylation of styrenes with NH4 SCN and water to from ß-hydroxysulfides is established. The reaction mechanism proceeded via a domino reaction after a radical addition to 2-phenylimidazo[1,2-a]pyridines. This approach features a wide substrate scope and functional group compatibility, providing 34 compounds in acceptable yields.

14.
Org Lett ; 26(7): 1338-1342, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38334428

RESUMO

A palladium-catalyzed (3 + 2) annulation of 2-methylbenzoic acid with maleimide using Ac-Leu-OH as a powerful ligand has been reported. Through a site-selective γ-C(sp3)-H olefination reaction and a sequential decarboxylative cross-coupling reaction, a five-membered cyclic ring was obtained as the final product. This novel reaction features great site selectivity and reactivity to generate various cyclic products in moderate to good yields.

15.
Cancer Lett ; 602: 217181, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39159882

RESUMO

Metastasis is the main cause of mortality in colorectal cancer (CRC) patients. Exploring the mechanisms of metastasis is of great importance in both clinical and fundamental CRC research. CRC is a highly heterogeneous disease with variable therapeutic outcomes of treatment. In this study, we applied spatial transcriptomics (ST) to generate a tissue-wide transcriptome from two primary colorectal cancer tissues and their matched liver metastatic tissues. Spatial RNA information showed intratumoral heterogeneity (ITH) of both primary and metastatic tissues. The comparison of gene expressions across tissues revealed an apparent enrichment of cancer stem cells (CSCs) in metastatic tissues and identified FOXD1 as a novel metastatic CSC marker. Trajectory and pseudo-time analyses revealed distinct evolutionary trajectories and a dedifferentiation-differentiation process during metastasis. CellphoneDB analysis suggested a dominant interaction of CD74-MIF with tumor cells in metastatic tissues. Further analysis confirmed FOXD1 as a maker of CSCs and the predictor of patient survival, especially in metastatic diseases. Our study found ITH of primary and metastatic tissues and provides novel insights into the cellular mechanisms underlying liver metastasis of CRC and foundations for therapeutic strategies for CRC metastasis.


Assuntos
Neoplasias Colorretais , Fatores de Transcrição Forkhead , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Transcriptoma , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/metabolismo , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Heterogeneidade Genética , Masculino , Feminino , Perfilação da Expressão Gênica/métodos
16.
Org Lett ; 25(31): 5875-5879, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37498107

RESUMO

C-H borylation is one of the powerful C-H bond functionalization reactions. In this context, a metal-free C-H borylation of benzophenones using hydrazone as the traceless directing group has been reported. The dibromoboron intermediates can be obtained in excellent yields, and the corresponding arylboronic esters are generated in moderate to excellent yields. Furthermore, the borylated compounds can be transformed in a one-pot method, avoiding the loss of overall yield caused by the separation of the arylboronic esters.

17.
Org Lett ; 25(27): 4962-4967, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37403974

RESUMO

A tandem diolefination reaction of benzaldehyde has been developed via Pd-catalyzed ß-C(sp2)-H olefination of the benzene ring and tandem C(sp2)-H olefination of acrylate. 2-((Aminooxy)methyl)benzonitrile was involved with the benzaldehyde substrate as a remote directing group to realize the C-H bond activation. The control experiments proved that the presence of a remote cyano group is essential for this novel diolefination reaction.


Assuntos
Benzaldeídos , Paládio , Paládio/química , Catálise , Estrutura Molecular
18.
Org Lett ; 25(51): 9136-9141, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38100569

RESUMO

Herein, we found that treating N-substituted pyrrole-2-carboxaldehydes with arylalkenes in DMF in N2 at 120 °C could afford pyrrolidine scaffolds with an up to 85% yield. This approach has several remarkable features, such as atom and step economy, readily accessible raw materials, and easy-to-operate manner, providing a simple and efficient method for constructing complicated bicyclic pyrroles. Additionally, we have successfully synthesized 28 target compounds, which further demonstrates its practicality and wide applicability.

19.
Int J Surg ; 109(12): 4073-4090, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37737848

RESUMO

BACKGROUND: To investigate the clinicopathological features and prognosis of synchronous and metachronous multiple primary colorectal cancer. MATERIALS AND METHODS: Patients who underwent operation for synchronous and metachronous colorectal cancer at the colorectal surgery department of Shanghai Changhai Hospital between January 2000 and December 2021 were included. Perioperative indicators were comprehensively compared and included in the survival analyses. RESULTS: In total, 563 patients with synchronous ( n =372) and metachronous ( n =191) colorectal cancer were included. Patients with synchronous colorectal cancer were more likely to have a long onset time, positive carcinoembryonic antigen, advanced TNM stage, large tumor, perineural invasion, p53 high expression, and mismatch repair proficient. Compared with metachronous colorectal cancer, patients with synchronous colorectal cancer showed worse 5-year overall survival (68.6±3.0% vs 81.9±3.5%, P =0.018) and 5-year disease-free survival (61.2±3.1% vs 71.0±3.9%, P =0.022). In the subgroup analysis, segmental resection was an independent risk factor for the long-term outcomes of bilateral synchronous colorectal cancer. CONCLUSIONS: Clinicopathological and molecular features were different between synchronous and metachronous colorectal cancer. Patients with synchronous colorectal cancer showed a worse prognosis than those with metachronous colorectal cancer. Bilateral synchronous colorectal cancer requires extended resection to achieve improved long-term outcomes.


Assuntos
Neoplasias Colorretais , Neoplasias Primárias Múltiplas , Segunda Neoplasia Primária , Humanos , Neoplasias Primárias Múltiplas/cirurgia , Segunda Neoplasia Primária/cirurgia , Estudos Retrospectivos , Neoplasias Colorretais/patologia , China/epidemiologia , Prognóstico
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