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Inspired by the superglue fuming method for fingerprint collection, this study developed a novel interfacial-fuming-induced surface instability process to generate wrinkled patterns on polymeric substrates. High-electronegativity groups are introduced on the substrate surface to initiate the polymerization of monomer vapors, such as ethyl cyanoacrylate, which results in the formation of a stiff poly(ethyl cyanoacrylate) capping layer. Moreover, interfacial polymerization resulted in the covalent bonding of the substrate, which led to the volumetric shrinkage of the composite and the accumulation of compressive strain. This process ultimately resulted in the development and stabilization of wrinkled surface morphologies. The authors systematically examined parameters such as the modulus of the epoxy substrate, prestrain, the flow rate of fuming, and operating temperature. The aforementioned technique can be easily applied to architectures with complex outer morphologies and inner surfaces, thereby enabling the construction of surface patterns under ambient conditions without vacuum limitations or precise process control. This study is the first to combine fuming-induced interfacial polymerization with surface instability to create robust wrinkles. The proposed method enables the fabrication of intricate microwrinkled patterns and has considerable potential for use in various practical applications, including microfluidics, optical components, bioinspired adhesive devices, and interfacial engineering.
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BACKGROUND: To compare the impact of tunneled cuffed catheters (TCCs) and arteriovenous fistulas (AVFs) on outcomes in elderly hemodialysis (HD) patients. METHODS: A retrospective matched cohort study was performed. Propensity score matching (PSM) was applied to balance the baseline conditions, and we compared all-cause mortality, major adverse cardiovascular and cerebrovascular events (MACCEs), hospitalization, and infection rates between AVF and TCC patients ≥70 years old. Cox survival analysis was used to analyze the risk factors for death. RESULTS: There were 2119 patients from our center in the Chinese National Renal Data System (CNRDS) between 1 January 2010 and 10 October 2023. Among these patients, 77 TCC patients were matched with 77 AVF patients. There was no significant difference in all-cause mortality between the TCC and AVF groups (30.1/100 vs. 33.3/100 patient-years, p = 0.124). Among the propensity score-matched cohorts, no significant differences in Kaplan-Meier curves were observed between the two groups (log-rank p = 0.242). The TCC group had higher rates of MACCEs, hospitalization, and infection than the AVF group (33.7/100 vs. 29.5/100 patient-years, 101.2/100 vs. 79.5/100 patient-years, and 30.1/100 vs. 14.1/100 patient-years, respectively). Multivariate analysis showed that high Charlson comorbidity index (CCI) score was a risk factor for death. CONCLUSIONS: There was no significant difference in all-cause mortality between elderly HD patients receiving TCCs and AVFs. Compared with those with a TCC, elderly HD patients with an AVF have a lower risk of MACCEs, hospitalization, and infection.
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Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica , Pontuação de Propensão , Diálise Renal , Humanos , Masculino , Feminino , Idoso , Estudos Retrospectivos , Falência Renal Crônica/terapia , Falência Renal Crônica/complicações , Falência Renal Crônica/mortalidade , Fatores de Risco , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Idoso de 80 Anos ou mais , Hospitalização/estatística & dados numéricos , China/epidemiologia , Prognóstico , Estimativa de Kaplan-MeierRESUMO
The chemistry of polypyridyl Ru(II) and cyclometalated Ir(III) derivatives provides long-lasting interest to researchers due to the inherent advantage of their triplet states in a variety of photoactivities. The introduction of Ru(N^N)3 and Ir(C^N)2(X^N) modules into well-defined architectures extends the research areas of both photoactive metal complexes and network chemistry, generating a lot of new opportunities with interesting structural aesthetics and profound functional possibilities. The rapid development of research in integrating Ru(II) or Ir(III) metallotecons into the architectures has been apparent in recent years which makes this a fascinating subject for reviewing. This review focuses on the design and syntheses of Ru(N^N)3 and Ir(C^N)2(X^N) functionalized architectures of metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), metallasupramolecules, organic supramolecules and supramolecular organic frameworks (SOFs). Furthermore, the photocatalytic applications including the hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2RR), photocatalytic oxidation and photoredox catalysis of organic transformation are also presented.
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A pregnant woman had a normal second-trimester anatomic survey at 22 weeks gestation. She was revealed to have a fetal oral mass with polyhydramnios and invisible stomach bubble by ultrasound at 28 weeks. A 50 mm × 36 mm × 42 mm, solid mass was found in the fetal mouth, filling the entire oral cavity. Fetal magnetic resonance imaging showed a homogeneous solid mass in the oral cavity compressing the hypopharynx. At 33 weeks, preterm labor occurred because of the continuation of increased amniotic fluid volume, and a female infant was vaginally delivered. The infant died shortly after tracheal intubation attempt failed. Autopsy confirmed the prenatal sonographic finding. The final pathologic diagnosis was oral immature teratoma. Our study indicates that although oral teratomas are rare, they are readily apparent at prenatal sonographic examinations. Respiratory compromise is the frequent complication of oral teratomas, which is associated with high perinatal mortality.
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BACKGROUND: Muscone is a chemical monomer derived from musk. Although many studies have confirmed the cardioprotective effects of muscone, the effects of muscone on cardiac hypertrophy and its potential mechanisms are unclear.The aim of the present study was to investigate the effect of muscone on angiotensin (Ang) II-induced cardiac hypertrophy. METHODS AND RESULTS: In the present study, we found for the first time that muscone exerted inhibitory effects on Ang II-induced cardiac hypertrophy and cardiac injury in mice. Cardiac function was analyzed by echocardiography measurement, and the degree of cardiac fibrosis was determined by the quantitative real-time polymerase chain reaction (qRT-PCR), Masson trichrome staining and western blot assay. Secondly, qRT-PCR experiment showed that muscone attenuated cardiac injury by reducing the secretion of pro-inflammatory cytokines and promoting the secretion of anti-inflammatory cytokines. Moreover, western blot analysis found that muscone exerted cardio-protective effects by inhibiting phosphorylation of key proteins in the STAT3, MAPK and TGF-ß/SMAD pathways. In addition, CCK-8 and determination of serum biochemical indexes showed that no significant toxicity or side effects of muscone on normal cells and organs. CONCLUSIONS: Muscone could attenuate Ang II-induced cardiac hypertrophy, in part, by inhibiting the STAT3, MAPK, and TGF-ß/SMAD signaling pathways.
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Traumatismos Cardíacos , Transdução de Sinais , Camundongos , Animais , Angiotensina II , Fator de Crescimento Transformador beta/metabolismo , Citocinas/metabolismo , Fibrose , Cardiomegalia/induzido quimicamenteRESUMO
BACKGROUND: Studies comparing the survival of hemodialysis (HD) and peritoneal dialysis (PD) patients are controversial. This study evaluated the impact of initial dialysis modality on the survival of patients with end-stage renal disease (ESRD) in a matched-pair cohort. METHODS: A retrospective cohort study was performed on ESRD patients who initiated renal replacement treatment between January 1, 2010, and December 31, 2018. Propensity score matching was applied to balance the baseline conditions, and multivariate Cox regression analysis was applied to compare mortality between HD and PD patients and evaluate correlations between mortality and various baseline characteristics. Subgroup analysis was performed with respect to diabetes status. RESULTS: There were 739 patients in our center in the Chinese National Renal Data System (CNRDS) between 2010 and 2018. Of these, 125 PD patients were matched with 125 HD patients. The 1-, 2-, and 3-year survival rates were 96.5%, 90.7%, and 82.5%, respectively, in the HD group and 99.5%, 97.8%, and 92.5%, respectively, in the PD group (log-rank P < 0.001). Among the propensity score-matched cohorts, no significant differences in Kaplan-Meier curves were observed between the two groups (log-rank P = 0.514). Age at dialysis initiation, CCI, congestive heart failure and cerebrovascular disease were risk factors in the multivariable-adjusted model. In subgroups defined by diabetes status, the KaplanâMeier survival curve showed that PD survival was significantly higher than that of HD (log-rank P = 0.022). CONCLUSIONS: HD and PD were not significantly different regarding the survival of patients with ESRD. PD was associated with better survival in diabetic ESRD patients.
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Diabetes Mellitus , Falência Renal Crônica , Humanos , Diálise Renal , Estudos Retrospectivos , Pontuação de Propensão , Falência Renal Crônica/complicações , Fatores de Risco , Modelos de Riscos ProporcionaisRESUMO
The impact of weather variability and air pollutants on tuberculosis (TB) has been a research hotspot. Previous studies have mostly been limited to a certain area or with a small sample size of cases, and multi-scale systematic studies are lacking. In this study, 14,816,329 TB cases were collected from 31 provinces in China between 2004 and 2018 to estimate the association between TB risk and meteorological factors and air pollutants using a two-stage time-series analysis. The impact and lagged time of meteorological factors and air pollutants on TB risk varied greatly in different provinces and regions. Overall cumulative exposure-response summary associations across 31 provinces suggested that high monthly mean relative humidity (RH) (66.8-82.4%, percentile56-100 (P56-100)), rainfall (316.5-331.1 mm, P96-100), PM2.5 exposure concentration (93.3-145.0 µg/m3, P58-100), and low monthly mean wind speed (1.6-2.1 m/s, P0-38) increased the risk of TB incidence, with a relative risk (RR) of 1.10 (95% CI: 1.04-1.16), 1.10 (95% CI: 1.03-1.16), 2.08 (95% CI: 1.18-3.65), and 2.06 (95% CI: 1.27-3.33), and attributable risk percent (AR%) of 9%, 9%, 52%, and 51%, respectively. Conversely, high monthly average wind speed (2.3-2.9 m/s, P54-100) and mean temperature (20.2-25.3 °C, P79-96), and low monthly average rainfall (2.4-25.2 mm, P0-7) and concentration of SO2 (8.1-21.2 µg/m3, P0-16) exposure decreased the risk of TB incidence, with an overall cumulative RR of 0.92 (95% CI: 0.87-0.98), 0.74 (95% CI: 0.59-0.94), 0.87 (95% CI: 0.79-0.95), and 0.72 (95% CI: 0.56-0.93), respectively. Our study provided insights into future planning of public health interventions for TB.
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Poluentes Atmosféricos , Poluição do Ar , Tuberculose , Humanos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Tuberculose/epidemiologia , Tuberculose/etiologia , Conceitos Meteorológicos , China/epidemiologia , Fatores de Risco , Material Particulado/análiseRESUMO
A visible light-induced Co-catalyzed highly regio- and stereoselective reductive coupling of vinyl azaarenes and alkynes has been developed. Notably, Hünig's base together with simple ethanol has been successfully applied as the hydrogen sources instead of commonly used Hantzsch esters in this catalytic photoredox reaction. This approach has considerable advantages for the straightforward synthesis of stereodefined multiple substituted alkenes bearing an azaarene motif, such as excellent regioselectivity (>20 : 1 for >30â examples) and stereoselectivity (>20 : 1â E/Z), broad substrate scope and good functional group compatibility under mild reaction conditions, which has been utilized in the concise synthesis of natural product monomorine I. A reasonable catalytic reaction pathway involving protolysis of the cobaltacyclopentene intermediate has been proposed based on the mechanistic studies.
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A new regio- and stereoselective reductive coupling of alkynes and crotononitrile has been developed via visible light organophotoredox cobalt dual catalysis. A variety of enantioenriched homoallylic nitriles bearing a stereodefined trisubstituted alkene have been easily synthesized with good to excellent regio- (up to >20:1 rr), stereo- (>20:1 E/Z), and enantioselectivity (up to 98% ee) control under mild conditions. The corresponding nitrile products were smoothly converted into various chiral building blocks. Remarkably, a simple organic base together with water have been utilized as hydrogen sources in this photoinduced reductive reaction.
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Alcinos , Nitrilas , Estrutura Molecular , EstereoisomerismoRESUMO
A new strategy for the direct cleavage of the C(sp3)-OH bond has been developed via activation of free alcohols with neutral diphenyl boryl radical generated from sodium tetraphenylborate under mild visible light photoredox conditions. This strategy has been verified by cross-electrophile coupling of free alcohols and carbon dioxide for the synthesis of carboxylic acids. Direct transformation of a range of primary, secondary, and tertiary benzyl alcohols to acids has been achieved. Control experiments and computational studies indicate that activation of alcohols with neutral boryl radical undergoes homolysis of the C(sp3)-OH bond, generating alkyl radicals. After reducing the alkyl radical into carbon anion under photoredox conditions, the following carboxylation with CO2 affords the coupling product.
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Álcoois , Dióxido de Carbono , Álcoois/química , Ácidos Carboxílicos , Catálise , LuzRESUMO
OBJECTIVE: To examine the diagnostic yield of exome sequencing (ES) in singleton pregnancies with isolated fetal clubfoot. METHODS: Clinical data from singleton pregnancies with a sonographic diagnosis of isolated clubfoot and ES results between 2018 and 2021 were retrospectively obtained from a single referral medical center. The recorded data include maternal age, gestational age at sonographic diagnosis, the indication for genetic testing, ES results, and pregnancy outcomes. RESULTS: During the study period, 38 fetuses were prenatally diagnosed with isolated clubfoot by ultrasound and underwent ES after the copy number variant analysis was non-diagnostic. Through the trio-ES analysis, pathogenic or likely pathogenic variants were detected in 4 of 38 (10.5%) with the following genes: BRPF1, ANKRD17, FLNA, and KIF1A. All are de novo with three of autosomal dominant inheritance and one of X-linked recessive inheritance. CONCLUSION: Sonographic diagnosis of clubfoot, even isolated, increases the risk for monogenic syndromes. Exome sequencing should be an option for genetic investigation for such pregnancies.
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Pé Torto Equinovaro , Gravidez , Feminino , Humanos , Sequenciamento do Exoma , Pé Torto Equinovaro/diagnóstico por imagem , Pé Torto Equinovaro/genética , Ultrassonografia Pré-Natal , Estudos Retrospectivos , Feto/diagnóstico por imagem , Diagnóstico Pré-Natal/métodos , Proteínas de Ligação a DNA , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ligação a RNA , CinesinasRESUMO
BACKGROUND: Parathyroidectomy (PTX) is a treatment for hyperparathyroidism (HPT) and has uncertain risks and benefits. The aim of this study was to evaluate the effect of PTX versus nonoperative treatment among nondiabetic hemodialysis patients. METHODS: A retrospective matched cohort study was performed. Each PTX patient was matched with one patient who had severe HPT but rejected PTX. The patients were matched by sex, birth date, date of first dialysis, nondiabetic status, and left ventricular ejection fraction. The serum markers, survival, main adverse cardiovascular and cerebrovascular event (MACCE) rates, and hospitalization were compared between the PTX patients and matched non-PTX patients. RESULTS: There were 1143 patients at our center in the Chinese National Renal Data System (CNRDS) between 2010 and 2020. Of these, 75 PTX patients were matched with 75 non-PTX patients. Rapid decreases in the mean intact parathyroid hormone, calcium and phosphorus concentrations, and a gradual increase in hemoglobin concentration were observed in the PTX group. The mortality was 2.9 per 100 patient-years in the PTX group and 10.9 per 100 patient-years in the non-PTX group (p < 0.001). Compared with non-PTX patients, PTX patients had an adjusted HR for death of 0.236 (95% CI 0.108-0.518). The cumulative MACCE rates were 6.7 per 100 patient-years in the PTX group and 15.2 per 100 patient-years in the non-PTX group (p < 0.001). The adjusted HR of the occurrence of first MACCE for PTX patients compared with non-PTX patients was 0.524 (95% CI 0.279-0.982). The cumulative hospitalization rates were 50.3 per 100 patient-years in the PTX group and 66.5 per 100 patient-years in the matched non-PTX group (p < 0.001). CONCLUSIONS: Compared with non-PTX patients, PTX was associated with an improvement in the biochemical measures and patient-level outcomes in nondiabetic hemodialysis patients with severe HPT.
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Hiperparatireoidismo Secundário , Hiperparatireoidismo , Falência Renal Crônica , Estudos de Coortes , Humanos , Hiperparatireoidismo Secundário/complicações , Hiperparatireoidismo Secundário/cirurgia , Falência Renal Crônica/cirurgia , Falência Renal Crônica/terapia , Hormônio Paratireóideo , Paratireoidectomia , Diálise Renal , Estudos Retrospectivos , Volume Sistólico , Função Ventricular EsquerdaRESUMO
INTRODUCTION: Kabuki syndrome (KS) is a multiple congenital anomaly syndrome with characterized facial features. The aim of study was to report on prenatal sonographic findings associated with KS in 7 Chinese families. CASE PRESENTATION: During the study period, 7 families of KS were diagnosed. Variants of KMT2D were detected in 4 cases, and variants of KDM6A in 3 cases. For cases with KMT2D variants, cleft palate was the only finding on second-trimester ultrasound in 2 cases. One case presented with polyhydramnios in late third trimester. One case showed ventricular septal defect and renal anomaly at 22 weeks gestation. For cases with KDM6A variants, one was detected at 22 weeks to have coarctation of the aorta. One presented with third-trimester intrauterine growth restriction. The other with hypoplastic left heart had a maternal KDM6A variant c.1227_1228del. Further family study showed that this variant was also present in the healthy maternal mother, but not in the healthy maternal father and two maternal brothers. The two female carriers were healthy. DISCUSSION/CONCLUSION: Although there is no specific ultrasound feature which has both high sensitivity and high positive predictive value for KS, this disorder should be considered as a differential diagnosis in fetuses with congenital anomalies including polyhydramnios with normal karyotyping/microarray analysis.
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Anormalidades Múltiplas , Feminino , Humanos , Masculino , Gravidez , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/genética , Histona Desmetilases/genética , Fenótipo , Poli-Hidrâmnios/genética , Diagnóstico Pré-Natal , HeterozigotoRESUMO
The aim of this study was to present prenatal ultrasound findings, molecular testing results and pregnancy outcomes of cases with 22q11.2 deletion (del22q11.2) diagnosed prenatally. A total of 76 foetuses were included. All cases were diagnosed by using chromosomal microarray analysis. Data on prenatal diagnosis, ultrasound findings, pregnancy outcomes and inheritance of del22q11.2 were reviewed. Congenital heart defects (CHDs) were the most common indications (47/76, 61.8%) for prenatal testing and were isolated in 52.6% (40/76). The constitution of CHDs comprised predominantly of conotruncal defects (61.7%; 29/47). Other cardiac anomalies were encountered in 38.3% (18/47) of cases. Extracardiac findings, including unilateral multicystic dysplastic kidney, clubfoot, increased nuchal translucency, intrauterine growth retardation and polyhydramnios, were found in 31.6% (24/76) of cases, and were combined with CHDs in 7 cases. Twelve cases had normal sonographic scans at the time of prenatal diagnosis. Foetal CHDs, especially conotruncal defects, are the most predictive association with del22q11.2. The information about del22q11.2 should also be part of the contents in comprehensive pre-test counselling even for those who are referred for diagnostic testing with foetal extracardiac findings.Impact statementWhat is already known on this subject? 22q11.2 deletion (del22q11.2) is the most common microdeletion syndrome in humans. At present, the main indications for prenatal testing for del22q11.2 are pregnancies of abnormal sonographic findings, especially foetal congenital heart defects.What do the results of this study add? Many extracardiac malformations, including some lethal or mildly non-specific ones, could be associated with foetal del22q11.2. There were also del22q11.2 foetuses had normal sonographic scans at the time of prenatal diagnosis.What are the implications of these findings for clinical practice and/or further research? The information about del22q11.2 should also be part of the contents in comprehensive pre-test counselling even for those who are referred for diagnostic testing with indications other than foetal cardiac anomalies.
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Doenças Fetais , Cardiopatias Congênitas , Feminino , Gravidez , Humanos , População do Leste Asiático , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/genética , Ultrassonografia Pré-Natal , Diagnóstico Pré-Natal , Feto , Estudos RetrospectivosRESUMO
A Co-catalyzed highly regio- and enantioselective reductive coupling of alkynes and aldehydes has been developed under visible light photoredox dual catalysis. A variety of enantioenriched allylic alcohols have been obtained by using unsymmetrical internal alkynes and commercially available catalyst, chiral ligand, and reagents. It is noteworthy that this approach has considerable advantages, such as excellent regio- (>95:5 for >40 examples), stereo- (up to >95:5 E/Z), and enantioselectivity (92-99% ee, >35 examples) control, mild reaction conditions, broad substrate scope, and good functional group compatibility, making it a great improvement to enantioselective alkyne-aldehyde reductive coupling reactions.
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INTRODUCTION: Studies have shown inconsistent results regarding the association between osteoprotegerin (OPG) concentration and cardiovascular mortality in patients with chronic kidney disease (CKD). This systematic review and meta-analysis aims to investigate the association between OPG concentration and cardiovascular mortality in patients with CKD. METHODS: Between January 1970 and February 2020, the PubMed, EMBASE, and Cochrane Library databases were searched for eligible studies investigating the association between OPG concentration and cardiovascular mortality in patients with CKD. Pooled hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were calculated using random effects models. RESULTS: In total, 10 studies comprising 2,120 patients (including 1,723 receiving dialysis) with CKD were included. The included studies were considered to be of fair to high quality. Patients in the highest OPG concentration group had a significantly higher risk of cardiovascular mortality (4 studies; adjusted HR, 2.05; 95% CI, 1.39-3.00) than patients in the low OPG concentration group. An increase of 1 pmol/L in OPG concentration was associated with a 4% increased risk of cardiovascular mortality (6 studies; adjusted HR, 1.04; 95% CI, 1.02-1.07). CONCLUSION: Elevated OPG concentrations are associated with an increased risk of cardiovascular death in patients with CKD.
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Doenças Cardiovasculares/complicações , Osteoprotegerina/análise , Insuficiência Renal Crônica/complicações , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/mortalidade , Humanos , Prognóstico , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/mortalidade , Fatores de RiscoRESUMO
OBJECTIVE. The purpose of this article is to describe the use of ultrasound-MRI fusion imaging to guide precise and targeted muscle biopsy in patients with suspected myopathies. CONCLUSION. Ultrasound-MRI fusion-guided muscle biopsy allows targeted sampling of tissues with active inflammatory changes and facilitates diagnosis of myopathies.
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Background: Studies have shown inconsistent results regarding the association between circulating osteoprotegerin (OPG) levels and all-cause mortality in patients with chronic kidney disease (CKD). The aim of this meta-analysis is to investigate the association between circulating OPG levels and all-cause mortality in patients with CKD. Methods: The PubMed, EMBASE and Cochrane Library databases were searched for eligible studies investigating the association between circulating OPG levels and all-cause mortality in patients with CKD. Pooled hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were calculated using a random effects model. Results: In all, 13 studies that included 2,895 patients with CKD were included in this analysis. According to the meta-analysis, patients with the highest circulating OPG level had a significantly higher risk of all-cause mortality (7 studies; the adjusted HR, 1.88; 95% CI, 1.45 - 2.44) compared with patients with the lower circulating OPG level. An increase of 1 pmol/L in the circulating OPG level was associated with a 6% increased risk of all-cause mortality (7 studies; the adjusted HR, 1.06; 95% CI, 1.03-1.10). A subgroup analysis by dialysis methods suggested that an elevated circulating OPG level was independently associated with all-cause mortality in the HD only population. Conclusion: Elevated circulating OPG levels independently predict an increased risk of all-cause mortality in patients with CKD, especially in the HD only population.
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Falência Renal Crônica/mortalidade , Osteoprotegerina/sangue , Biomarcadores/sangue , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Valor Preditivo dos Testes , Prognóstico , Diálise Renal/estatística & dados numéricos , Fatores de RiscoRESUMO
Amide bond formation is one of the most important reactions in organic chemistry because of the widespread presence of amides in pharmaceuticals and biologically active compounds. Existing methods for amides synthesis are reaching their inherent limits. Described herein is a novel rhodium-catalyzed three-component reaction to synthesize amides from organic azides, carbon monoxide, and (hetero)arenes via nitrene-intermediates and direct C-H functionalization. Notably, the reaction proceeds in an intermolecular fashion with N2 as the only by-product, and either directing groups nor additives are required. The computational and mechanistic studies show that the amides are formed via a key Rh-nitrene intermediate.
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Sirt family has been reported playing a significant role in the cancer development, especial its deacetylase activity plays a key function, but whether SIRT6 plays a role in mediating tumor epithelial-mesenchymal transition (EMT) and metastasis in colon cancer has not been explored. Here, the mass spectrometry and co-immunoprecipitation assays were utilized to detect that SIRT6 was physically associated with transcription factor snail. Most important, HCT116 cells transfected with SIRT6 shRNA reversed EMT, while increased the expression of TET1, and the HCT116 cells transfected with SIRT6 displayed the contrary tendency. Transwell invasion assay, soft agar assay, as well as colony formation together showed that SIRT6 promoted cell EMT and tumorigenesis in vitro. We also found SIRT6 is a reader of snail. ChIP as well as qChIP suggested H3K9 binding on the promoter of TET1 dependent on SIRT6. SIRT6 promoted EMT process through two different ways, one is as a reader of snail, and other way was the suppression of TET1 transcription. These two ways are all dependent on its H3K9 deacetylase activity. Further, patient samples collected showed that SIRT6 was significantly increased in colon cancer samples, and its higher expression was correlated with poor prognosis, worse overall survivals. Together, our experiments revealed the mechanism for SIRT6 in facilitating tumorigenesis and metastasis of colon cancer cells, suggesting that SIRT6 might be a potential therapeutic target for treating colon cancer.