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1.
Org Lett ; 26(24): 5115-5119, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38862412

RESUMEN

An ammonium ylide-based relay annulation was disclosed, which uses DABCO as the catalyst and oxindole-derived α,ß-unsaturated ketimines and γ-bromo-crotonates as the starting materials. This method enables the rapid assembly of a series of structurally novel spiro-polycyclic oxindoles containing a bicyclo[4.1.0]heptane moiety through simultaneous generation of three new bonds and two rings in one step under mild reaction conditions.

2.
Chem Sci ; 15(20): 7502-7514, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38784726

RESUMEN

The exploitation of new reactive species and novel transformation modes for their synthetic applications have significantly promoted the development of synthetic organic methodology, drug discovery, and advanced functional materials. α-Iminyl radical cations, a class of distonic ions, exhibit great synthetic potential for the synthesis of valuable molecules. For their generation, radical conjugate addition to α,ß-unsaturated iminium ions represents a concise yet highly challenging route, because the in situ generated species are short-lived and highly reactive and they have a high tendency to cause radical elimination (ß-scission) to regenerate the more stable iminium ions. Herein, we report a new transformation mode of the α-iminyl radical cation, that is to say, 1,5-hydrogen atom transfer (1,5-HAT). Such a strategy can generate a species bearing multiple reactive sites, which serves as a platform to realize (asymmetric) relay annulations. The present iron/secondary amine synergistic catalysis causes a modular assembly of a broad spectrum of new structurally fused pyridines including axially chiral heterobiaryls, and exhibits good functional group tolerance. A series of mechanistic experiments support the α-iminyl radical cation-induced 1,5-HAT, and the formation of several radical species in the relay annulations. Various synthetic transformations of the reaction products demonstrate the usefulness of this relay annulation protocol for the synthesis of significant molecules.

3.
Org Lett ; 26(7): 1358-1363, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38345019

RESUMEN

A metal-free three-component protocol that combines a hydroxylamine-Passerini reaction and hetero-Cope rearrangement was realized, which enables the modular assembly of a wide range of structurally new and interesting 2-aminoanilines bearing an α-hydroxyamide substructure.

4.
Dis Colon Rectum ; 66(11): 1481-1491, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37643197

RESUMEN

BACKGROUND: Stage II/III disease is the most predominant form of colorectal cancer, accounting for approximately 70% of cases. Furthermore, approximately 15% to 20% of patients with stage II/III disease have deficient mismatch repair or microsatellite instability-high colorectal cancer. However, there are no identified significant prognostic biomarkers for this disease. OBJECTIVE: To identify prognostic markers for patients with deficient mismatch repair/microsatellite instability-high colon cancer stage II/III. DESIGN: Retrospective study design. SETTING: The study was conducted at a high-volume colorectal center, the Cancer Hospital, Chinese Academy of Medical Sciences. PATIENTS: Patients diagnosed with stage II/III deficient mismatch repair/microsatellite instability-high colon cancer who underwent curative surgery at the Cancer Hospital at the Chinese Academy of Medical Sciences between July 2015 and November 2018 were included. MAIN OUTCOME MEASURES: The primary outcome measure was the influence of differentially mutated genes on progression-free survival. RESULTS: The retrospective deficient mismatch repair/microsatellite instability-high cohort involved 32 patients and The Cancer Genome Atlas-microsatellite instability-high cohort involved 45 patients. Patients with deficient mismatch repair/microsatellite instability-high colon cancer had higher mutational frequencies of MKI67 , TPR , and TCHH than patients with microsatellite stable colon cancer. MKI67 , TPR , TCHH , and gene combination were significantly correlated with prognosis. The biomarker mutation-type colon cancer group had a higher risk of recurrence or death than did the wild-type group. Moreover, biomarker mutation-type tumors had more mutations in the DNA damage repair pathway and tumor mutational burden than did biomarker wild-type tumors. LIMITATIONS: This study was limited by its retrospective nature. CONCLUSIONS: MKI67 , TPR , and TCHH may serve as potential diagnostic and prognostic biomarkers for deficient mismatch repair/microsatellite instability-high colon cancer stage II/III. IDENTIFICACIN DE MUTACIONES MKI, TPR Y TCHH COMO BIOMARCADORES PRONSTICOS PARA PACIENTES CON CNCER DE COLON EN ETAPA II/III CON DEFICIENCIA EN LA REPARACION DE ERRORES DE EMPAREJAMIENTO: ANTECEDENTES:La enfermedad en estadio II/III es la forma más predominante de cáncer colorrectal y representa aproximadamente el 70% de los casos. Además, aproximadamente entre el 15% y el 20% de los pacientes con enfermedad en estadio II/III tienen reparación deficiente de errores de emparejamiento o inestabilidad de microsatélital alta. Sin embargo, no se han identificado biomarcadores pronósticos significativos para esta enfermedad.OBJETIVO:Este estudio tuvo como objetivo identificar marcadores pronósticos para pacientes con cáncer de colon con reparación deficiente de errores de emparejamiento/inestabilidad microsatelital alta en estadio II/III.DISEÑO:Diseño de estudio retrospectivo.ESCENARIO:El estudio se realizó en un centro colorrectal de alto volumen, el Hospital del Cáncer de la Academia China de Ciencias Médicas.PACIENTES:Pacientes diagnosticados con cáncer de colon en estadio II/III con reparación deficiente de errores de emparejamiento o inestabilidad de microsatélital alta que se sometieron a cirugía curativa en el Hospital del Cáncer de la Academia China de Ciencias Médicas entre julio de 2015 y noviembre de 2018.MEDIDAS DE RESULTADO PRINCIPALES:La medida de resultado primaria fue la influencia de los genes con mutaciones diferenciales en la supervivencia libre de progresión.RESULTADOS:La cohorte retrospectiva de reparación deficiente de errores de emparejamiento o inestabilidad de microsatélital alta y la cohorte de inestabilidad microsatelital alta del Atlas del Genoma del Cáncer involucraron a 32 y 45 pacientes, respectivamente. Los pacientes con de reparación deficiente de errores de emparejamiento/inestabilidad microsatélital alta tuvieron frecuencias mutacionales más altas de MKI67 , TPR y TCHH que los pacientes estables de microsatélites. MKI67 , TPR , TCHH , y la combinación de genes se correlacionaron significativamente con el pronóstico. El grupo de cáncer de colon de tipo mutación de biomarcador tenía un mayor riesgo de recurrencia o muerte que el grupo de mutación salvaje. Además, los tumores de tipo mutación de biomarcadores tenían más mutaciones en la vía de reparación del daño del ADN y la carga mutacional del tumor que los tumores de tipo salvaje de biomarcadores.LIMITACIONES:Este estudio estuvo limitado por su naturaleza retrospectiva.CONCLUSIONES:MKI67 , TPR , y TCHH pueden servir como posibles biomarcadores de diagnóstico y pronóstico para cáncer de colon en estadio II/III con reparación deficiente de errores de emparejamiento/inestabilidad microsatélital alta. (Traducción-Dr. Jorge Silva Velazco ).


Asunto(s)
Neoplasias del Colon , Reparación de la Incompatibilidad de ADN , Humanos , Antígenos , Neoplasias del Colon/genética , Neoplasias del Colon/cirugía , Reparación de la Incompatibilidad de ADN/genética , Proteínas de Filamentos Intermediarios , Inestabilidad de Microsatélites , Mutación , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Antígeno Ki-67/genética
5.
Org Biomol Chem ; 21(34): 6926-6931, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37578205

RESUMEN

Reported here is the synthesis of a naphthalene-based macrocycle bearing anionic carboxylato groups on the rims along with its complexation with cationic guests in aqueous media. The macrocycle could strongly bind guests in a molecular clip model with association constants of 106-107 M-1.

6.
J Minim Access Surg ; 19(3): 440-442, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37282427

RESUMEN

Transverse colon cancer accounts for about 10% of all colonic cancers. The resection of cancers in the transverse colon is technically more challenging, compared with other cancer locations in the colon because the variable anatomy of the middle colic vessels demands excellent surgical skills and the anatomical location of the transverse colon is related to major organs. We report a novel laparoscopic technique for the first time used in surgery of transverse colon cancer which combines a total intracorporeal anastomosis with natural orifice specimen extraction to solve the problems of traditional laparoscopic surgery. A 48-year-old male patient, whose diagnosis was transverse colon adenocarcinoma, was admitted to the hospital. The surgery was performed in accordance with the procedure of totally laparoscopic right hemicolectomy and the specimen was extracted by opening the rectum. Natural orifice specimen extraction surgery has many advantages, including less pain, better cosmesis and minimising risks of complications and also has comparable long-term outcomes compared to conventional laparoscopic surgery.

7.
Front Immunol ; 14: 1093716, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37006239

RESUMEN

Background: Programmed cell death protein 1 (PD-1) receptor has two ligands,programmed death-ligand 1 (PD-L1) and PD-L2. When compared with PD-L1, PD-L2 has not received much attention, and its role remains unclear. Methods: The expression profiles of pdcd1lg2 (PD-L2-encoding gene) mRNA and PD-L2 protein were analyzed using TCGA, ICGC, and HPA databases. Kaplan-Meier and Cox regression analyses were used to assess the prognostic significance of PD-L2. We used GSEA, Spearman's correlation analysis and PPI network to explore the biological functions of PD-L2. PD-L2-associated immune cell infiltration was evaluated using the ESTIMATE algorithm and TIMER 2.0. The expressions of PD-L2 in tumor-associated macrophages (TAMs) in human colon cancer samples, and in mice in an immunocompetent syngeneic setting were verified using scRNA-seq datasets, multiplex immunofluorescence staining, and flow cytometry. After fluorescence-activated cell sorting, flow cytometry and qRT-PCR and transwell and colony formation assays were used to evaluate the phenotype and functions of PD-L2+TAMs. Immune checkpoint inhibitors (ICIs) therapy prediction analysis was performed using TIDE and TISMO. Last, a series of targeted small-molecule drugs with promising therapeutic effects were predicted using the GSCA platform. Results: PD-L2 was expressed in all the common human cancer types and deteriorated outcomes in multiple cancers. PPI network and Spearman's correlation analysis revealed that PD-L2 was closely associated with many immune molecules. Moreover, both GSEA results of KEGG pathways and GSEA results for Reactome analysis indicated that PD-L2 expression played an important role in cancer immune response. Further analysis showed that PD-L2 expression was strongly associated with the infiltration of immune cells in tumor tissue in almost all cancer types, among which macrophages were the most positively associated with PD-L2 in colon cancer. According to the results mentioned above, we verified the expression of PD-L2 in TAMs in colon cancer and found that PD-L2+TAMs population was not static. Additionally, PD-L2+TAMs exhibited protumor M2 phenotype and increased the migration, invasion, and proliferative capacity of colon cancer cells. Furthermore, PD-L2 had a substantial predictive value for ICIs therapy cohorts. Conclusion: PD-L2 in the TME, especially expressed on TAMs, could be applied as a potential therapeutic target.


Asunto(s)
Neoplasias del Colon , Animales , Humanos , Ratones , Antígeno B7-H1 , Carcinógenos , Neoplasias del Colon/genética , Pronóstico , Microambiente Tumoral
8.
J Ethnopharmacol ; 312: 116502, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37068718

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Threatened abortion is a common disease among women of childbearing age. Its high incidence rate and unclear etiology, seriously threaten women's physical and mental health. Shoutai Wan (STW) is a traditional Chinese medicine decoction for treating abortion. It has a long history of treating threatened abortion by tonifying the kidney and calming the fetus. However, the mechanism of STW remains unclear. AIM OF STUDY: To study the mechanism and potential benefit of STW in pregnant mice with hydrocortisone and mifepristone-induced threatened abortion. MATERIALS AND METHODS: The STW compounds were identified using gas chromatography-mass spectrometry analysis. STW-H, STW-M, or STW-L was separately given 3 mg/ml, 1.5 mg/ml and 0.75 mg/ml STW in the morning, and 2 mg/ml hydrocortisone in the afternoon from gestation day (D) 1-9 and once with 0.4 mg/kg mifepristone on D10. Didroxyprogesterone (0.1 mg/ml) and equal dose pure water were used to replace STW in didroxyprogesterone (DYD) group and model group respectively. The control group used pure water to replace STW, hydrocortisone, and mifepristone. We performed morphological and histological analyses of the maternal-fetal interface on day 10. RESULTS: The embryo loss rate in the STW-H and DYD groups was lower than that in the model group. Hematoxylin and eosin (HE) staining suggested that the morphology of maternal-fetal interface was improved in the STW-H and DYD groups. Immunohistochemical (IHC), Quantitative Reverse Transcription Polymerase Chain Reactionstaining (qRT-PCR), and Western blot (WB) results indicated that HIF-1α expression in the maternal-fetal interface of the STW-H and DYD groups was higher than that in model group. The activities of HK, PKM, LDH and the concentration of lactic acid in the STW-H and DYD groups were higher than those in model group. Furthermore, the protein and mRNA levels of HK2, PKM2, LDHA, MCT4, and GPR81 were higher in the STW-H and DYD groups than those in the model group. CONCLUSIONS: STW can reduce the pregnancy loss rate by regulating the glycolysis balance at the maternal-fetal interface of kidney deficiency threatened abortion model mice.


Asunto(s)
Aborto Inducido , Aborto Espontáneo , Amenaza de Aborto , Embarazo , Humanos , Ratones , Femenino , Animales , Amenaza de Aborto/tratamiento farmacológico , Mifepristona/farmacología , Hidrocortisona
9.
Front Oncol ; 13: 1067414, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36959789

RESUMEN

Purpose: Total laparoscopic anterior resection (tLAR) has been gradually applied in the treatment of rectal cancer (RC). This study aims to develop a scoring system to predict the surgical difficulty of tLAR. Methods: RC patients treated with tLAR were collected. The blood loss and duration of excision (BLADE) scoring system was built to assess the surgical difficulty by using restricted cubic spline regression. Multivariate logistic regression was used to evaluate the effect of the BLADE score on postoperative complications. The random forest (RF) algorithm was used to establish a preoperative predictive model for the BLADE score. Results: A total of 1,994 RC patients were randomly selected for the training set and the test set, and 325 RC patients were identified as the external validation set. The BLADE score, which was built based on the thresholds of blood loss (60 ml) and duration of surgical excision (165 min), was the most important risk factor for postoperative complications. The areas under the curve of the predictive RF model were 0.786 in the training set, 0.640 in the test set, and 0.665 in the external validation set. Conclusion: This preoperative predictive model for the BLADE score presents clinical feasibility and reliability in identifying the candidates to receive tLAR and in making surgical plans for RC patients.

10.
Eur J Surg Oncol ; 49(7): 1258-1268, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36653246

RESUMEN

BACKGROUND: Total laparoscopic anterior resection (tLAR) and natural orifice specimen extraction surgery (NOSES) has been widely adopted in the treatment of rectal cancer (RC). However, no study has been performed to predict the short-term outcomes of tLAR using machine learning algorithms to analyze a national cohort. METHODS: Data from consecutive RC patients who underwent tLAR were collected from the China NOSES Database (CNDB). The random forest (RF), extreme gradient boosting (XGBoost), support vector machine (SVM), deep neural network (DNN), logistic regression (LR) and K-nearest neighbor (KNN) algorithms were used to develop risk models to predict short-term complications of tLAR. The area under the receiver operating characteristic curve (AUROC), Gini coefficient, specificity and sensitivity were calculated to assess the performance of each risk model. The selected factors from the models were evaluated by relative importance. RESULTS: A total of 4313 RC patients were identified, and 667 patients (15.5%) developed postoperative complications. The machine learning model of XGBoost showed more promising results in the prediction of complication than other models (AUROC 0.90, P < 0.001). The performance was similar when internal and external validation was used. In the XGBoost model, the top four influential factors were the distance from the lower edge of the tumor to the anus, age at diagnosis, surgical time and comorbidities. In risk stratification analysis, the rate of postoperative complications in the high-risk group was significantly higher than in the medium- and low-risk groups (P < 0.001). CONCLUSION: The machine learning model shows potential benefits in predicting the risk of complications in RC patients after tLAR. This novel approach can provide reliable individual information for surgical treatment recommendations.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Humanos , Estudios Retrospectivos , Neoplasias del Recto/cirugía , Laparoscopía/efectos adversos , Laparoscopía/métodos , Complicaciones Posoperatorias/etiología , Aprendizaje Automático , Algoritmos
11.
Molecules ; 27(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36500315

RESUMEN

In the presence of CuOAc, a series of unsymmetric ureas can be generated in moderate to good yields under mild reaction conditions (10 mol% of CuOAc, 2 equiv t-BuONa or PhONa, 30 °C), using aryl isocyanides and O-benzoyl hydroxylamines as the readily accessible starting materials. The reactions might undergo a cascade process involving isocyanide insertion into the N-O bond and Mumm-type rearrangement. This work represents a rare example of isocyanide insertion into N-O bonds, which would extend isocyanide insertion chemistry.


Asunto(s)
Cobre , Cianuros , Cianuros/química , Cobre/química , Catálisis , Estructura Molecular , Urea
12.
World J Clin Cases ; 8(1): 157-167, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31970182

RESUMEN

BACKGROUND: Isolated gastrointestinal venous malformations (GIVMs) are extremely rare congenital developmental abnormalities of the venous vasculature. Because of their asymptomatic nature, the diagnosis is often quite challenging. However, as symptomatic GIVMs have nonspecific clinical manifestations, misdiagnosis is very common. Here, we report a case of isolated diffuse GIVMs inducing mechanical intestinal obstruction. A literature review was also conducted to summarize clinical features, diagnostic points, treatment selections and differential diagnosis in order that doctors may have a comprehensive understanding of this disease. CASE SUMMARY: A 50-year-old man presented with recurrent painless gastrointestinal bleeding for two months and failure to pass flatus and defecate with nausea and vomiting for ten days. Digital rectal examination found bright red blood and soft nodular masses 3 cm above the anal verge. Computed tomography showed that part of the descending colon and rectosigmoid colon was thickened with phleboliths in the intestinal wall. Colonoscopy exhibited bluish and reddish multinodular submucosal masses and flat submucosal serpentine vessels. Endoscopic ultrasonography showed anechoic cystic spaces within intestinal wall. The lesions were initially thought to be isolated VMs involving part of the descending colon and rectosigmoid colon. Laparoscopic subtotal proctocolectomy, pull-through transection and coloanal anastomosis and ileostomy were performed. Histopathology revealed intact mucosa and dilated, thin-walled blood vessels in the submucosa, muscularis, and serosa involving the entire colorectum. The patient recovered with complete symptomatic relief during the 52-mo follow-up period. CONCLUSION: The diagnosis of isolated GIVMs is challenging. The information presented here is significant for the diagnosis and management of symptoms.

13.
Brain Res ; 1685: 91-104, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29408500

RESUMEN

MicroRNAs (miRNAs) are a class of non-coding small RNAs that regulate the expression of target genes. They derive from pre-miRNAs that are enzymatically processed by dicer to ∼22 nucleotide mature miRNAs. Members of the pre-miRNA lethal-7 (let-7) are known to regulate cell proliferation and apoptosis. Here, we showed that the level of let-7c-5p, a key member of the let-7 family, was rapidly reduced in the traumatically injured foci in brains of adult C57BL/6J mice and gradually recovered to the pre-injury level 14 days after traumatic brain injury (TBI) induction. This finding led us to test whether upregulating let-7c-5p in murine cerebral tissue by intracerebroventricular injection (ICV) of let-7c-5p mimic could improve the outcomes of mice subjected to controlled cortical impact (CCI). We found that let-7c-5p overexpression attenuated TBI-induced neurological dysfunction and brain edema. The improvements were attributed to let-7c-5p-mediated inhibiting neuroinflammation and attenuation of microglia/macrophage activation, both inhibiting M1 polarization and enhancing M2 polarization. In vitro experiments, we observed that let-7c-5p was decreased in primary microglia activated by LPS treatment or oxygen/glucose deprivation (OGD). Transfection of let-7c-5p mimic suppressed the release of inflammatory mediators in cultured activated primary microglia. In addition, the expressions of caspase-3, a let-7c-5p putative target gene, and the PKC-δ which mediates effect of caspase-3 were inhibited by let-7c-5p in a murine model of TBI. Taken together, these results define the biological activities of cerebral let-7c-5p and delineate its therapeutic potential for improving the neurological outcome of TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/metabolismo , Inflamación/genética , MicroARNs/genética , Microglía/metabolismo , Animales , Apoptosis/fisiología , Edema Encefálico/metabolismo , Proliferación Celular/fisiología , Modelos Animales de Enfermedad , Activación de Macrófagos/genética , Macrófagos/metabolismo , Masculino , Ratones Endogámicos C57BL
14.
Oncol Res Treat ; 40(1-2): 35-41, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28118629

RESUMEN

BACKGROUND: The purpose of this study was to evaluate the clinical significance and prognostic roles of vasculogenic mimicry (VM) and elucidate their intrinsic association with molecular markers. METHODS: 89 human gastric cancer cases with detailed follow-up and clinicopathologic data were collected. CD34/periodic acid-Schiff double staining was performed to validate the existence of VM. Immunohistochemistry was performed to explore the expression of different molecular factors. RESULTS: VM was observed in 24 gastric cancer patients. They were prone to higher histological grade, hematogenous metastasis, distant recurrence, and chance of progression to stage III or IV (p < 0.05). The VM group had shorter overall and disease-free survival (p < 0.05). VM negativity was independently prognostic for prolonged overall or disease-free survival (p < 0.05). VM was positively associated with levels of matrix metalloproteinase-2, matrix metalloproteinase-9, vascular endothelial growth factor, and vascular endothelial growth factor receptor-1 (p < 0.05), but not with vascular endothelial growth factor receptor-2 (p > 0.05). CONCLUSION: VM should be regarded as a good marker to indicate pathobiological behaviors of gastric cancer. Using antibodies against matrix metalloproteinases, vascular endothelial growth factor, or vascular endothelial growth factor receptors could be strategies to counteract VM formation.


Asunto(s)
Neovascularización Patológica/patología , Neoplasias Gástricas/irrigación sanguínea , Neoplasias Gástricas/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Persona de Mediana Edad , Clasificación del Tumor , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/patología , Pronóstico , Neoplasias Gástricas/mortalidad , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
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