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1.
BMC Plant Biol ; 24(1): 453, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789944

RESUMEN

BACKGROUND: Impatiens is an important genus with rich species of garden plants, and its distribution is extremely extensive, which is reflected in its diverse ecological environment. However, the specific mechanisms of Impatiens' adaptation to various environments and the mechanism related to lignin remain unclear. RESULTS: Three representative Impatiens species,Impatiens chlorosepala (wet, low degree of lignification), Impatiens uliginosa (aquatic, moderate degree of lignification) and Impatiens rubrostriata (terrestrial, high degree of lignification), were selected and analyzed for their anatomical structures, lignin content and composition, and lignin-related gene expression. There are significant differences in anatomical parameters among the stems of three Impatiens species, and the anatomical structure is consistent with the determination results of lignin content. Furthermore, the thickness of the xylem and cell walls, as well as the ratio of cell wall thickness to stem diameter have a strong correlation with lignin content. The anatomical structure and degree of lignification in Impatiens can be attributed to the plant's growth environment, morphology, and growth rate. Our analysis of lignin-related genes revealed a negative correlation between the MYB4 gene and lignin content. The MYB4 gene may control the lignin synthesis in Impatiens by controlling the structural genes involved in the lignin synthesis pathway, such as HCT, C3H, and COMT. Nonetheless, the regulation pathway differs between species of Impatiens. CONCLUSIONS: This study demonstrated consistency between the stem anatomy of Impatiens and the results obtained from lignin content and composition analyses. It is speculated that MYB4 negatively regulates the lignin synthesis in the stems of three Impatiens species by regulating the expression of structural genes, and its regulation mechanism appears to vary across different Impatiens species. This study analyses the variations among different Impatiens plants in diverse habitats, and can guide further molecular investigations of lignin biosynthesis in Impatiens.


Asunto(s)
Impatiens , Lignina , Tallos de la Planta , Lignina/metabolismo , Tallos de la Planta/genética , Tallos de la Planta/anatomía & histología , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/metabolismo , Impatiens/genética , Impatiens/metabolismo , Impatiens/crecimiento & desarrollo , Ecosistema , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptación Fisiológica/genética , Regulación de la Expresión Génica de las Plantas , Especificidad de la Especie , Genes de Plantas , Pared Celular/metabolismo , Pared Celular/genética
2.
BMC Med ; 22(1): 407, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304842

RESUMEN

BACKGROUND: Kidney transplantation is the optimal renal replacement therapy for children with end-stage renal disease; however, delayed graft function (DGF), a common post-operative complication, may negatively impact the long-term outcomes of both the graft and the pediatric recipient. However, there is limited research on DGF in pediatric kidney transplant recipients. This study aims to develop a predictive model for the risk of DGF occurrence after pediatric kidney transplantation by integrating donor and recipient characteristics and utilizing machine learning algorithms, ultimately providing guidance for clinical decision-making. METHODS: This single-center retrospective cohort study includes all recipients under 18 years of age who underwent single-donor kidney transplantation at our hospital between 2016 and 2023, along with their corresponding donors. Demographic, clinical, and laboratory examination data were collected from both donors and recipients. Univariate logistic regression models and differential analysis were employed to identify features associated with DGF. Subsequently, a risk score for predicting DGF occurrence (DGF-RS) was constructed based on machine learning combinations. Model performance was evaluated using the receiver operating characteristic curves, decision curve analysis (DCA), and other methods. RESULTS: The study included a total of 140 pediatric kidney transplant recipients, among whom 37 (26.4%) developed DGF. Univariate analysis revealed that high-density lipoprotein cholesterol (HDLC), donor after circulatory death (DCD), warm ischemia time (WIT), cold ischemia time (CIT), gender match, and donor creatinine were significantly associated with DGF (P < 0.05). Based on these six features, the random forest model (mtry = 5, 75%p) exhibited the best predictive performance among 97 machine learning models, with the area under the curve values reaching 0.983, 1, and 0.905 for the entire cohort, training set, and validation set, respectively. This model significantly outperformed single indicators. The DCA curve confirmed the clinical utility of this model. CONCLUSIONS: In this study, we developed a machine learning-based predictive model for DGF following pediatric kidney transplantation, termed DGF-RS, which integrates both donor and recipient characteristics. The model demonstrated excellent predictive accuracy and provides essential guidance for clinical decision-making. These findings contribute to our understanding of the pathogenesis of DGF.


Asunto(s)
Funcionamiento Retardado del Injerto , Trasplante de Riñón , Aprendizaje Automático , Donantes de Tejidos , Humanos , Trasplante de Riñón/efectos adversos , Femenino , Masculino , Niño , Estudios Retrospectivos , Adolescente , Preescolar , Lactante
3.
Org Biomol Chem ; 22(37): 7596-7600, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39221612

RESUMEN

A straightforward copper-catalyzed deborodeuteration of arylboronic acids and borates was achieved, employing the cost-effective deuterium source D2O. This protocol demonstrates wide substrate applicability, exceptional deuterium incorporation efficiency, and favorable tolerance for various functional groups. Therefore, this approach offers a mild option for further applications in valuable deuterium molecule synthesis.

4.
Org Biomol Chem ; 22(33): 6695-6698, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39106103

RESUMEN

Addressing the challenge of constructing multi-substituted dihydropyrans, we present an efficient synthesis method for oxygen-containing heterocycles. Using thiones and metal carbenes, we employed xanthate and triazole to intramolecularly synthesize dihydropyran or dihydrofuran compounds. 1,2-Hydride migration was inhibited, and thiodihydropyrans were obtained in excellent yields. A mechanism proceeding through a Rh-carbene intermediate is proposed for the multi-substituted dihydropyrans synthesis.

5.
BMC Gastroenterol ; 24(1): 347, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39363264

RESUMEN

BACKGROUND: This study aimed to compare the survival outcomes of transarterial chemoembolization (TACE) between patients with early recurrent hepatocellular carcinoma (rHCC) after hepatic resection, stratified by cytokeratin (CK) 19 expression. METHODS: A retrospective analysis was conducted on 63 patients with early rHCC after hepatic resection who underwent TACE between January 2017 and December 2021. Patients were divided into two groups based on CK19 expression: CK19-negative (n=31) and CK19-positive (n=32). Overall survival (OS) and progression-free survival (PFS) were compared between the two groups using the Kaplan-Meier method and log-rank test. Cox regression analysis was performed to identify independent risk factors for OS and PFS. RESULTS: The CK19-negative group demonstrated a significantly longer median OS compared to the CK19-positive group (635 days vs. 432 days, p=0.013). Similarly, the CK19-negative group had a longer median PFS than the CK19-positive group (291 days vs. 117 days, p=0.014). Multivariate Cox analysis identified Child-Pugh A grade, CK19-negative expression, and increased TACE sessions as protective factors for OS. No severe TACE-related adverse events were observed. CONCLUSION: In patients with early rHCC after hepatic resection, those with CK19-positive expression had poorer survival outcomes following TACE compared to CK19-negative patients. These findings suggest the need for additional therapies to improve survival in CK19-positive individuals.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Hepatectomía , Queratina-19 , Neoplasias Hepáticas , Recurrencia Local de Neoplasia , Humanos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/cirugía , Quimioembolización Terapéutica/métodos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/cirugía , Queratina-19/metabolismo , Queratina-19/análisis , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Pronóstico , Anciano , Biomarcadores de Tumor/metabolismo , Estimación de Kaplan-Meier , Adulto , Supervivencia sin Progresión
6.
Cardiology ; : 1-12, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39342934

RESUMEN

INTRODUCTION: The aim of this study was to evaluate the utility of 2D-STI and real-time three-dimensional echocardiography (RT-3DE) in assessing changes in left atrial (LA) structure and function in patients with paroxysmal atrial fibrillation (PAF) post-radiofrequency catheter ablation (RFCA). METHODS: A retrospective analysis was conducted on 44 PAF patients who underwent RFCA at BA Hospital from March 2022 to March 2023. An age- and gender-matched control group of 32 healthy individuals was also included. Comprehensive echocardiographic parameters including LA dimensions (LAAPD, LALRD), volumes (LAVmin, LAVmax), ejection fraction (LAEF), and tissue velocities (a', Ar) were compared between groups. Post-RFCA changes in these parameters were also assessed at 1, 3, and 6 months. RESULTS: Pre-RFCA, PAF patients demonstrated larger LA dimensions and volumes with reduced LAEF and tissue velocities compared to controls. Post-RFCA, there was a significant improvement in LAEF and left ventricular ejection fraction at 1, 3, and 6 months, with the most pronounced changes observed at 6 months. LA dimensions increased initially but then decreased from 1 to 6 months post-RFCA. Notably, strain rate (SRS, SRE, SRA) measurements in various LA segments improved progressively, with the most significant enhancements at 6 months, suggesting improved atrial mechanics. CONCLUSION: The application of 2D-STI and RT-3DE provides a quantitative means to evaluate the structural and functional changes in the LA of PAF patients following RFCA. The progressive improvements in LA dimensions, volumes, and strain measurements up to 6-month post-RFCA indicate the potential of these techniques in monitoring treatment efficacy and patient recovery.

7.
BMC Musculoskelet Disord ; 25(1): 398, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773475

RESUMEN

OBJECTIVE: to investigate the association between cartilage lesion-related features observed in knee osteoarthritis (OA) patients' first MRI examination and incident knee surgery within 5 years. Additionally, to assess the predictive value of these features for the incident knee surgery. METHODS: We identified patients diagnosed with knee OA and treated at our institution between January 2015 and January 2018, and retrieved their baseline clinical data and first MRI examination films from the information system. Next, we proceeded to determine joint space narrowing grade, cartilage lesion size grade, cartilage full-thickness loss grade and cartilage lesion sum score for the medial and lateral compartments, respectively. Generalized linear regression models examined the association of these features with 5-year incident knee surgery. Positive and negative predictive values (PPVs and NPVs) were determined referring to 5-year incident knee surgery. RESULTS: Totally, 878 participants (knees) were found eligible to form the study population. Within the 5 years, surgery was performed on 61 knees. None of the cartilage-related features had been found significantly associated with incident surgery. The results were similar for medial and lateral compartments. The PPVs were low for all the features. CONCLUSIONS: Among symptomatic clinically diagnosed OA knees, cartilage lesions observed in the first MRI examinations were not found to be associated with the occurrence of joint surgery within a 5-year period. All these cartilage-related features appear to have no additional value in predicting 5-year incident joint surgery.


Asunto(s)
Cartílago Articular , Articulación de la Rodilla , Imagen por Resonancia Magnética , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/cirugía , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/epidemiología , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Cartílago Articular/cirugía , Anciano , Articulación de la Rodilla/cirugía , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Artroplastia de Reemplazo de Rodilla/estadística & datos numéricos
8.
Artículo en Inglés | MEDLINE | ID: mdl-39332935

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a common malignancy with high mortality. Liver resection (LR) is a curative treatment for early-stage HCC, but the prognosis of HCC patients after LR is unsatisfactory because of tumor recurrence. Prognostic prediction models with great performance are urgently needed. The present study aimed to establish a novel prognostic nomogram to predict tumor recurrence in HCC patients after LR. METHODS: We retrospectively analyzed 726 HCC patients who underwent LR between October 2011 and December 2016. Patients were randomly divided into the training cohort (n = 508) and the testing cohort (n = 218). The protein expression of 14 biomarkers in tumor tissues was assessed by immunohistochemistry. The nomogram predicting recurrence-free survival (RFS) was established by a multivariate Cox regression analysis model and was evaluated by calibration curves, Kaplan-Meier survival curves, time-dependent areas under the receiver operating characteristic (ROC) curves (AUCs), and decision curve analyses in both the training and testing cohorts. RESULTS: Alpha-fetoprotein [hazard ratio (HR) = 1.013, P = 0.002], portal vein tumor thrombosis (HR = 1.833, P < 0.001), ascites (HR = 2.024, P = 0.014), tumor diameter (HR = 1.075, P < 0.001), E-cadherin (HR = 0.859, P = 0.011), EMA (HR = 1.196, P = 0.022), and PCNA (HR = 1.174, P = 0.031) immunohistochemistry scores were found to be independent factors for RFS. The 1-year and 3-year AUCs of the nomogram for RFS were 0.813 and 0.739, respectively. The patients were divided into the high-risk group and the low-risk group by median value which was generated from the nomogram, and Kaplan-Meier analysis revealed that the high-risk group had a shorter RFS than the low-risk group in both the training (P < 0.001) and testing cohorts (P < 0.001). CONCLUSIONS: Our newly developed nomogram integrated clinicopathological data and key gene expression data, and was verified to have high accuracy in predicting the RFS of HCC patients after LR. This model could be used for early identification of patients at high-risk of postoperative recurrence.

9.
Opt Express ; 31(10): 16535-16548, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157730

RESUMEN

A detector with both broad operation range and high sensitivity is desirable in the measurement of weak periodic forces. Based on a nonlinear dynamical mechanism of locking the mechanical oscillation amplitude in optomechanical systems, we propose a force sensor that realizes the detection through the cavity field sidebands modified by an unknown external periodic force. Under the mechanical amplitude locking condition, the unknown external force happens to modify the locked oscillation amplitude linearly to its magnitude, thus achieving a linear scaling between the sideband changes read by the sensor and the magnitude of the force to be measured. This linear scaling range is found to be comparable to the applied pump drive amplitude, so the sensor can measure a wide range of force magnitude. Because the locked mechanical oscillation is rather robust against thermal perturbation, the sensor works well at room temperature. In addition to weak periodic forces, the same setup can as well detect static forces, though the detection ranges are much narrower.

10.
J Org Chem ; 88(13): 9543-9553, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37307412

RESUMEN

A catalyst-free cascade reaction of 3-(2-isocyanoethyl)indoles and 1-sulfonyl-1,2,3-triazoles was realized. This dearomative spirocyclization provided an efficient protocol to synthesize a series of polycyclic indolines bearing spiro-α-carboline in moderate to high yields in one step under thermal reaction conditions.


Asunto(s)
Indoles , Triazoles , Estereoisomerismo , Catálisis
11.
Org Biomol Chem ; 21(29): 5935-5938, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37435711

RESUMEN

A facile and efficient synthetic method for 3-aminoquinolines has been reported. The straightforward process starts from easily available triazoles and 2-aminobenzaldehydes. Low catalyst loading and good functional group compatibility are the other two merits of this transformation. Easy decoration of the 3-aminoquinoline motifs enabled the convenient synthesis of bioactive molecules, demonstrating the potential of this protocol in organic synthesis.

12.
Org Biomol Chem ; 21(45): 8979-8983, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37934046

RESUMEN

The synthesis of stereo-defined α-trifluoromethyl arylenes is of great importance in medical chemistry, organic chemistry, and materials science. However, despite the recent advances, the Z-selective formation of α-trifluoromethyl arylenes has remained underdeveloped. Here, we describe a facile approach towards Z-α-trifluoromethyl arylenes through Pd-catalysed stereoselective fluoroarylation of 1,1-difluoroallenes in the presence of a bulky monophosphine ligand.

13.
J Appl Microbiol ; 134(4)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36965871

RESUMEN

AIMS: Pandoraea pnomenusa MCB032 completely degrades chlorobenzene, whose metabolic pathway is encoded by cbs and clc gene clusters. The putative regulatory factors ClcR and CbsR are predicted to regulate the cbs and clc gene clusters. This research aims to understand the function of ClcR and CbsR. METHODS AND RESULTS: RT-PCR analyses demonstrated that the cbsFAaAbAcAdB operon that encodes catabolic pathways for the degradation of chlorobenzene to chlorocatechol is located on an operon. Moreover, the clcABCDE operon is involved in the 3-chlorocatechol pathway. Gene knockout and transcriptional analysis showed that the transcription of the cbsFAaAbAcAdB operon is positively regulated by CbsR, whereas the clcABCDE operon is activated by ClcR. Primer extension analysis was used to locate the transcription start sites of the cbsFAaAbAcAdB and cbsR operons. Electrophoretic mobility shift assay analyses showed that CbsR is bound to the sites in the promoter regions of cbsFAaAbAcAdB and cbsR operons. CONCLUSION: The XylR/NtrC-type regulator CbsR positively regulates the transcription of the cbsFAaAbAcAdB operon encoding the upstream pathway of chlorobenzene catabolism, while the LysR-type regulator ClcR activates the clcABCDE operon encoding the downstream pathway.


Asunto(s)
Clorobencenos , Factores de Transcripción , Factores de Transcripción/genética , Regiones Promotoras Genéticas , Secuencia de Bases , Clorobencenos/metabolismo , Operón , Regulación Bacteriana de la Expresión Génica , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
14.
Environ Res ; 220: 115258, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36634895

RESUMEN

The compound 3,5-xylenol is an essential precursor used in pesticides and industrial intermediate in the disinfectants and preservatives industry. Its widespread application makes it an important source of pollution. Microbial bioremediation is more environmentally friendly than the physicochemical treatment process for removing alkylphenols from a polluted environment. However, the 3,5-xylenol-degrading bacteria is unavailable, and its degradation mechanism remains unclear. Here, a 3,5-xylenol-metabolizing bacterial strain, designated Rhodococcus sp. CHJ602, was isolated using 3,5-xylenol as the sole source of carbon and energy from a wastewater treatment factory. Results showed that strain CHJ602 maintained a high 3,5-xylenol-degrading performance under the conditions of 30.15 °C and pH 7.37. The pathway involved in 3,5-xylenol degradation by strain CHJ602 must be induced by 3,5-xylenol. Based on the identification of intermediate metabolites and enzyme activities, this bacterium could oxidize 3,5-xylenol by a novel metabolic pathway. One methyl oxidation converted 3,5-xylenol to 3-hydroxymethyl-5-methylphenol, 3-hydroxy-5-methyl benzaldehyde, and 3-hydroxy-5-methylbenzoate. After that, another methyl oxidation is converted to 5-hydroxyisophthalicate, which is metabolized by the protocatechuate pathway. It is catalyzed by a series of enzymes in strain CHJ602. In addition, toxicity bioassay result indicates that 3,5-xylenol is toxic to zebrafish and Rhodococcus sp. CHJ602 could eliminate 3,5-xylenol in water to protect zebrafish from its toxicity. The results provide insights into the bioremediation of wastewater contaminated 3,5-xylenol.


Asunto(s)
Rhodococcus , Pez Cebra , Animales , Pez Cebra/metabolismo , Rhodococcus/metabolismo , Xilenos , Oxidación-Reducción , Biodegradación Ambiental
15.
Ophthalmic Res ; 66(1): 664-671, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36858031

RESUMEN

INTRODUCTION: This study analyzed the effectiveness of 650-nm red-light feeding instruments in the control of myopia. METHODS: In this study, 164 school-aged participants diagnosed with myopia in the city of Shenzhen were enrolled in a red-light feeding instrument study. Of these, 41 were enrolled in the mild-to-moderate myopia group that received red-light feeding (RLMM group), 65 were enrolled in the mild-to-moderate myopia group that received single-vision spectacle treatment (SVSMM group), and 58 were included in the severe myopia group that received red-light feeding (RLS group). RESULTS: After the baseline values of the three groups were matched, the right eye data were used for statistical analysis. The average return visit time of each group was 60.42 days, and changes in the observation indexes before treatment and after follow-up treatment were compared. As the primary outcome, the axial length changes in the right eye of the SVSMM group (0.08 ± 0.40 mm), the RLMM group (-0.03 ± 0.11 mm), and the RLS group (-0.07 ± 0.11 mm) were compared and showed a statistical result of p < 0.001. CONCLUSION: The study results verified that red light had a noticeable effect on the control of myopia and that low-level red-light therapy played a vital role in the treatment of severe myopia.


Asunto(s)
Miopía , Refracción Ocular , Humanos , Niño , Miopía/terapia , Ojo , Luz Roja , Anteojos
16.
BMC Cancer ; 22(1): 1244, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36456931

RESUMEN

BACKGROUND: Acid phosphatase type 6 (ACP6) is a mitochondrial lipid phosphate phosphatase that played a role in regulating lipid metabolism and there is still blank in the clinico-pathological significance and functional roles of ACP6 in human cancers. No investigations have been conducted on ACP6 in hepatocellular carcinoma (HCC) up to date. METHODS: Herein, we appraised the clinico-pathological significance of ACP6 in HCC via organizing expression profiles from globally multi-center microarrays and RNA-seq datasets. The molecular basis of ACP6 in HCC was explored through multidimensional analysis. We also carried out in vitro and in vivo experiment on nude mice to investigate the effect of knocking down ACP6 expression on biological functions of HCC cells, and to evaluate the expression variance of ACP6 in xenograft of HCC tissues before and after the treatment of NC. RESULTS: ACP6 displayed significant overexpression in HCC samples (standard mean difference (SMD) = 0.69, 95% confidence interval (CI) = 0.56-0.83) and up-regulated ACP6 performed well in screening HCC samples from non-cancer liver samples. ACP6 expression was also remarkably correlated with clinical progression and worse overall survival of HCC patients. There were close links between ACP6 expression and immune cells including B cells, CD8 + T cells and naive CD4 + T cells. Co-expressed genes of ACP6 mainly participated in pathways including cytokine-cytokine receptor interaction, glucocorticoid receptor pathway and NABA proteoglycans. The proliferation and migration rate of HCC cells transfected with ACP6 siRNA was significantly suppressed compared with those transfected with negative control siRNA. ACP6 expression was significantly inhibited by nitidine chloride (NC) in xenograft HCC tissues. CONCLUSIONS: ACP6 expression may serve as novel clinical biomarker indicating the clinical development of HCC and ACP6 might be potential target of anti-cancer effect by NC in HCC.


Asunto(s)
Fosfatasa Ácida , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Ratones , Fosfatasa Ácida/genética , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Ratones Desnudos , ARN Interferente Pequeño
17.
Org Biomol Chem ; 20(14): 2802-2807, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35311858

RESUMEN

Tetrahydrocarbazoles and pyrrolo[3,4-b]carbazoles could be synthesized conveniently through sequential reactions of ester-tethered 1-sulfonyl-1,2,3-triazoles and indoles. The reaction conditions were mild and the procedures were quite simple. Moreover, the key intermediate α,ß-unsaturated imine acted as a [2C] synthon in the [4 + 2] cycloaddition reaction, and the imino group could be used as a nucleophile to construct the fourth ring.


Asunto(s)
Carbazoles , Indoles , Reacción de Cicloadición , Ésteres , Triazoles
18.
Planta Med ; 88(8): 628-638, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34293804

RESUMEN

Flueggea suffruticosa is a traditional Chinese medicine that has been commonly used for the treatment of inflammatory ailments, including rheumatism and lumbago. Suffrutines A and suffrutines B are a pair of novel E,E and Z,E isomeric indolizidine alkaloids isolated from the roots of F. suffruticosa. However, their anti-inflammatory activity has not been reported thus far. The aim of this study was to investigate the inhibitory effect of inflammatory mediators and possible mechanisms of suffrutines A and B in lipopolysaccharide-induced RAW264.7 cells. Results showed that suffrutines A and B could remarkably inhibit the production of nitric oxide, prostaglandin E2, interleukin-6, inducible nitric oxide synthase, and cyclooxygenase-2 in lipopolysaccharide-induced RAW264.7 cells. Further evaluation demonstrated that compared with suffrutines A, suffrutines B could more significantly inhibit the phosphorylation of IKKα/ß, the degradation of IκBα, and the nuclear translocation of the p65 and p52 subunits in the canonical and non-canonical nuclear factor-κB pathways. Therefore, suffrutines B exhibited more potent inhibitory activity on inflammatory mediators than suffrutines A.


Asunto(s)
Lipopolisacáridos , FN-kappa B , Animales , Ciclooxigenasa 2/metabolismo , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/farmacología , Ratones , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Células RAW 264.7 , Transducción de Señal
19.
J Prosthet Dent ; 2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35489836

RESUMEN

STATEMENT OF PROBLEM: Thin root dentin after post space preparation will increase the risk of root fracture. However, the minimum residual root dentin thickness to be preserved after post space preparation is unclear. PURPOSE: The purpose of this finite element analysis (FEA) study was to measure the residual root dentin thicknesses and analyze the stress distributions of post-restored mandibular premolars. MATERIAL AND METHODS: The cone beam computed tomography (CBCT) data of 90 first and second mandibular premolars from Chinese participants (44 men, 46 women; aged between 20 and 79 years) were analyzed. Cross-sections 5 to 9 mm from the radiologic apex were used to measure the buccolingual and mesiodistal root diameters. The probability that the residual thickness of the buccolingual and mesiodistal root walls would be no less than 0.5, 0.6, 0.7, 0.8, 0.9, and 1 mm after post space preparation with a #2 Peeso reamer was calculated. Six 3-dimensional finite element models of cast post-restored mandibular premolars with 0.5, 0.6, 0.7, 0.8, 0.9, and 1 mm mesial and distal root dentin thicknesses were established. A static force of 100 N was applied to the buccal cusp tip at 45, 60, 75, and 90 degrees to the long axis of the tooth, and the maximum tensile stress and von Mises stress were analyzed. The Bonferroni post hoc test (αcorrected=.003) was used for multiple comparisons. RESULTS: The buccolingual root diameter of mandibular premolars was wider than the mesiodistal root diameter. The probabilities that the mesiodistal residual root dentin thickness of mandibular first and second premolars at 5 mm from the apex would be no less than 1 mm after post space preparation with a #2 Peeso reamer were only 10% and 28%, respectively. The maximum tensile stress was at a minimum when the mesial and distal residual root dentin thickness was 0.6 mm in the external cervical dentin adjacent to the crestal bone and 1 mm in the apical dentin corresponding to the apex of the post. The maximum tensile stress of the mandibular premolar model with 0.6-mm mesial and distal residual root dentin thicknesses was lower than that with 0.9 mm and 1.0 mm thicknesses (Pcorrected<.001). CONCLUSIONS: Short posts or smaller instruments for post space preparation are recommended to obtain a 1-mm residual root dentin thickness in the mesiodistal direction of mandibular premolars. If a 1-mm thickness cannot be preserved, a minimum residual root dentin thickness of 0.6 to 0.9 mm in the mesiodistal direction should be retained.

20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(1): 72-80, 2022 Feb.
Artículo en Zh | MEDLINE | ID: mdl-35300768

RESUMEN

Objective To investigate the expression and the potential roles of long non-coding RNA(lncRNA)cancer susceptibility candidate 2(CASC2)and imprinted gene H19 in extrahepatic cholangiocarcinoma(ECC). Methods Four samples from patients with ECC were collected for high-throughput sequencing which was conducted to reveal the transcriptomic profiles of lncRNA CASC2 and H19.Bioinformatics tools were employed to predict the potential roles of the two genes.Another 22 ECC tissue samples and the cholangiocarcinoma cell lines(RBE,QBC939,HuH-28,and HuCCT1)with different degrees of differentiation were selected for validation.The para-carcinoma tissue and normal human intrahepatic biliary epithelial cell(HIBEC)were used as the control groups.The expression levels of lncRNA CASC2 and H19 in carcinoma tissue,para-carcinoma tissue,and cell lines were determined by real-time quantitative polymerase chain reaction(qRT-PCR).The correlation analysis was carried out for the clinical indicators of patients with the expression levels of the target genes. Results The two target genes showed significantly different expression between carcinoma tissue and para-carcinoma tissue(all P<0.05).Specifically,CASC2 had higher expression level in the carcinoma tissue than in the para-carcinoma tissue(t=1.262,P=0.025),whereas the expression of H19 showed an opposite trend(t=1.285,P=0.005).The expression levels of CASC2 in QBC939(t=8.114,P=0.015)and HuH-28(t=9.202,P=0.012)cells were significantly higher than that in the control group.The expression levels of H19 were significantly lower in RBE(t=-10.244,P<0.001),QBC939(t=-10.476,P<0.001),HuH-28(t=-19.798,P<0.001),and HuCCT1(t=-16.193,P=0.004)cells than in the control group.Bioinformatics analysis showed that CASC2 was mainly involved in the metabolic process and H19 in the development of multicellular organisms.Both CASC2 and H19 were related to catalytic activity.The expression level of lncRNA CASC2 was correlated with pathological differentiation(χ 2=6.222,P=0.022)and lymph node metastasis(χ2=5.455,P=0.020),and that of lncRNA H19 with pathological differentiation(χ2=1.174,P=0.029)and tumor size(χ2=-0.507,P=0.037). Conclusions In the case of ECC,lncRNA CASC2 and H19 have transcription disorders.lncRNA CASC2 is generally up-regulated in the carcinoma tissue,while H19 is down-regulated.Both genes have the potential to become new molecular markers for ECC.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , ARN Largo no Codificante , Proteínas Supresoras de Tumor , Neoplasias de los Conductos Biliares/genética , Conductos Biliares Intrahepáticos/metabolismo , Colangiocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Humanos , ARN Largo no Codificante/genética , Proteínas Supresoras de Tumor/genética
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