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1.
Org Lett ; 26(17): 3509-3513, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38652867

RESUMO

Five-carbon (C5) units are the fundamental building blocks that constitute a multitude of natural products. Herein we report an unprecedented unusual C5 functionalization of indole regioselectively at the C-2-position enabled by a (2-pyridyl)sulfonyl-directing palladium-catalyzed dehydrogenative strategy with a bulk chemical 2-methyl-2-butene as a C5 source. Compared to typical C5 functionalization using pentenyl alcohols, carbonates, borates, or halides as the C5 source, the protocol not only has a low cost advantage but also is of atom and step economy.

2.
Org Lett ; 26(18): 3878-3882, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38678578

RESUMO

The synthesis of complex alkanes by the tetrafunctionalization of alkynes is limited and challenging. Herein, an unprecedented efficient geminal diazidation and dibromination of terminal alkynes is developed, which provides novel access to structurally diverse organic azides. The approach has exclusive chemo- and regioselectivity and features mild reaction conditions, good tolerance of various functional groups, and more crucially, no metal involved in the reaction, thereby benefiting the late-stage decoration of medicinal molecules. A mechanistic study showed that the current geminal diazidation and dibromination proceeds via a radical pathway.

3.
Nat Commun ; 15(1): 2415, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499520

RESUMO

Phenols and anilines are of extreme importance for medicinal chemistry and material science. The development of efficient approaches to prepare both compounds has thus long been a vital research topic. The utility of phenols and anilines directly reflects the identity and pattern of substituents on the benzenoid ring. Electrophilic substitutions remain among the most powerful synthetic methods to substituted phenols and anilines, yet in principle achieving ortho- and para-substituted products. Therefore, the selective preparation of meta-substituted phenols and anilines is the most significant challenge. We herein report an efficient copper-catalyzed dehydrogenation strategy to exclusively synthesize meta-carbonyl phenols and anilines from carbonyl substituted cyclohexanes. Mechanistic studies indicate that this transformation undergoes a copper-catalyzed dehydrogenation/allylic hydroxylation or amination/oxidative dehydrogenation/aromatization cascade process.

4.
Chemistry ; 29(37): e202300933, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37040176

RESUMO

Bulk chemical 2-methyl-2-butene, one of the main C5 distillates of the petrochemical industry, has scarcely been utilized directly in synthesizing high-value-added fine chemicals. Herein, we use 2-methyl-2-butene as the starting material to develop a palladium-catalyzed highly site- and regio-selective C-3 dehydrogenation reverse prenylation of indoles. This synthetic method features mild reaction conditions, a broad substrate scope, atom- and step-economies.

5.
Molecules ; 28(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36985470

RESUMO

5,6-Dihydrophenanthridines are common aza heterocycle frameworks of natural products and pharmaceuticals. Herein, we reported the first palladium-catalyzed intramolecular C-H/C-H dehydrogenative coupling reaction of two simple arenes to generate 5,6-dihydrophenanthridines. The approach features a broad substrate scope and good tolerance of functional groups, offering an efficient alternative synthesis route for important 5,6-dihydrophenanthridine compounds.

6.
Front Immunol ; 13: 1036181, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36544760

RESUMO

Background: Pediatric colorectal carcinoma (PCRC) is a rare non-embryonal tumor with an incidence of 0.1% to 1% of adults. Immune checkpoint inhibitors (ICIs) targeting programmed death-1 (PD-1) have shown significant efficacy in defective mismatch repair/Microsatellite instability-high (dMMR/MSI-H) metastatic CRC (mCRC). Although several studies have reported neoadjuvant immunotherapy (NIT) in MSI-H/dMMR non-mCRC patients, not all patients achieved pathological complete remission (pCR). There are differences between PCRC and adult colorectal carcinoma (CRC), and the role of NIT in PCRC remains to be further defined. Case presentation: We report the case of a 12-year-old child who was admitted to the hospital with abdominal pain and vomiting for more than 3 months. The child's diagnosis was difficult and complex. He was initially diagnosed with intestinal obstruction, eventually diagnosed with a rare PCRC and identified as locally advanced colorectal cancer (LACRC) with genetic sequencing results showing MSI-H. After a thorough evaluation by clinicians, he received 4 cycles of Camrelizumab (anti-PD-1 antibody) + CapeOx (capecitabine and oxaliplatin) NIT combination chemotherapy. Repeat imaging and all tumor markers were unremarkable, and R0 resection was achieved. Postoperative pathology showed a tumor regression grade (TRG) of 0 grade determined as pCR. Postoperative review has not shown any recurrence or metastasis to date and the prognosis is good. Conclusion: PCRC should improve the diagnostic efficiency to prevent misdiagnosis and miss the best time for treatment. NIT and or chemotherapy can be a reasonable and effective treatment option for dMMR/MSI-H locally advanced PCRC. Our report provides some support and evidence for neoadjuvant immunotherapy for locally advanced PCRC, while highlighting the importance of preoperative detection of microsatellite status for locally advanced PCRC.


Assuntos
Carcinoma , Neoplasias Colorretais , Neoplasias Retais , Masculino , Adulto , Humanos , Criança , Terapia Neoadjuvante/métodos , Neoplasias Colorretais/genética , Neoplasias Retais/terapia , Imunoterapia
7.
Medicine (Baltimore) ; 101(43): e31231, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36316936

RESUMO

INTRODUCTION: Necrotizing fasciitis (NF) is a rare, severe soft tissue infection, characterized by rapid and extensive necrosis of the skin, subcutaneous tissue, and superficial and deep fascia. It is frequently misdiagnosed as other infectious diseases, leading to inappropriate treatment and potentially serious consequences. It may be complicated by septic shock and multiple organ failure with a fatal outcome. PATIENT CONCERNS: A 73-year-old woman presented with continuous itching, skin lesions, pain, and swelling of the outer side of her left leg. The patient was diagnosed with septic shock and multiorgan failure caused by left leg NF. DIAGNOSIS: Septic shock and multiorgan failure caused by left leg NF. INTERVENTIONS: Two surgeries were performed on the patient's leg, which effectively treated her septic shock and multiple organ dysfunction. OUTCOMES: The patient was followed up three times after her discharge. She had a good recovery, was generally well with no significant sequelae, and returned to her regular life. CONCLUSION: NF is an acute severe illness with high mortality. It is easily misdiagnosed, leading to delayed or erroneous treatment and serious (or potentially fatal) outcomes. Rapid and accurate diagnosis of NF is essential for patient recovery. In difficult cases, multidisciplinary consultations may be helpful. The management of NF includes early and thorough surgical debridement, antibiotics, and symptomatic treatment.


Assuntos
Fasciite Necrosante , Choque Séptico , Humanos , Feminino , Idoso , Fasciite Necrosante/diagnóstico , Fasciite Necrosante/cirurgia , Choque Séptico/etiologia , Perna (Membro) , Diagnóstico Tardio/efeitos adversos , Antibacterianos/uso terapêutico
8.
Front Surg ; 9: 932296, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225218

RESUMO

Objective: This study aims to compare the efficacy and safety of freehand atlantoaxial pedicle screws against custom 3D printed navigation template screws in the treatment of upper cervical fractures. Methods: In our institution from 2010 to 2020, a retrospective cohort analysis of 23 patients with upper cervical fractures was done. These patients were separated into two groups: group A (N = 12), which received customized 3D printed navigation template-assisted screws with virtual reality techniques, and group B (N = 11), which received freehand screws assisted by intraoperative fluoroscopy. Every patient was monitored for more than 1 year. The two groups were contrasted in terms of screw implant accuracy, cervical spine Japanese Orthopaedic Association (JOA) score, American Spinal Injury Association (ASIA) score, visual analogue scale (VAS) score, surgical time, fluoroscopy times, and intraoperative blood loss. Results: A total of 88 atlantoaxial pedicle screws in all, 46 in group A and 42 in group B, were implanted. In group A, the screw insertion accuracy rate was 95.7%, compared to 80.0% in group B (P < 0.05). When compared to group B, group A had shorter surgery times, less blood loss, fewer fluoroscopies, a higher short-term JOA score, and overt pain reduction (P < 0.05). However, there was no discernible difference between the two groups' VAS scores, long-term JOA scores, or ASIA scores (sensory and motor), at the most recent follow-up. Conclusion: Individualized 3D printed guide leads to significant improvement in the screw safety, efficacy, and accuracy, which may be a promising strategy for the treatment of upper cervical fractures.

9.
J Org Chem ; 87(10): 6573-6587, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35522737

RESUMO

A new chemistry of azo compounds, that is, addition of free radicals generated in situ to access various acyl hydrazides, has been developed. The protocol provides a novel strategy for the synthesis of valuable acyl hydrazides. The transformation features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. In view of the importance of acyl hydrazides in functional materials and medicinal chemistry, this approach would find broad applications.


Assuntos
Ésteres , Hidrazinas , Ésteres/química , Radicais Livres , Hidrazinas/química
10.
Chemistry ; 28(39): e202200981, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35487846

RESUMO

A new class of electrophilic monofluoromethylselenolation reagents, Se-(fluoromethyl) benzenesulfonoselenoates, has been developed. They can be readily prepared from sodium benzenesulfinates, Se powder and ClCFH2 in one step under mild reaction conditions. Se-(fluoromethyl) benzenesulfonoselenoates are efficient electrophilic monofluoromethylselenolation reagents for a wide range of nucleophiles including indole, 6-azaindole, pyrrole, thiophene, electron-rich arene, aryl boronic acid and alkyne. The monofluoromethylselenolation approach features mild and environmentally friendly reaction conditions, good tolerance of various functional groups, and broad substrate scope.


Assuntos
Alcinos , Ácidos Borônicos , Elétrons , Indicadores e Reagentes
11.
J Org Chem ; 87(9): 5730-5743, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35471034

RESUMO

An efficient Pd-catalyzed C(sp3)-H selective iodination of 8-methylquinolines is reported herein for the first time. Because of the versatility of organic iodides, the method offers a facile access to various C8-substituted quinolines. By slightly switching the reaction conditions, an efficient C(sp3)-H acetoxylation of 8-methylquinolines has also been enabled. Both approaches feature mild reaction conditions, good tolerance of functional groups, and a broad substrate scope.

12.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(2): 132-140, 2022 Feb 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-35209977

RESUMO

OBJECTIVES: To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China. METHODS: A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined. RESULTS: The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05). CONCLUSIONS: It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.


Assuntos
Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Feminino , Retardo do Crescimento Fetal , Idade Gestacional , Hospitalização , Humanos , Incidência , Lactente , Recém-Nascido , Estudos Prospectivos , Fatores de Risco
13.
Cardiovasc Res ; 118(8): 1947-1963, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34324657

RESUMO

AIMS: Increased resistin (Retn) levels are associated with development of cardiovascular diseases. However, the role of Retn in heart failure (HF) is still unclear. Here we probed the functional and molecular mechanism underlying the beneficial effect of Retn deletion in HF. METHODS AND RESULTS: Wild-type (WT) and adipose tissue-specific Retn-knockout (RKO) mice were subjected to transverse aortic constriction (TAC)-induced HF. Cardiac function and haemodynamic changes were measured by echocardiography and left ventricular catheterization. Adipose tissue Retn deletion attenuated while Retn cardiac-selective overexpression, via a recombinant adeno-associated virus-9 vector, exacerbated TAC-induced hypertrophy, cardiac dysfunction, and myocardial fibrosis in WT and RKO mice. Mechanistically, we showed that Gadd45α was significantly increased in RKO HF mice while cardiac overexpression of Retn led to its downregulation. miR148b-3p directly targets Gadd45α and inhibits its expression. Retn overexpression upregulated miR148b-3p expression and triggered DNA damage response (DDR) in RKO-HF mice. Inhibition of miR148b-3p in vivo normalized Gadd45α expression, decreased DDR, and reversed cardiac dysfunction and fibrosis. In vitro Retn overexpression in adult mouse cardiomyocytes activated miR148b-3p and reduced Gadd45α expression. Gadd45α overexpression in H9C2-cardiomyoblasts protected against hydrogen peroxide- and Retn-induced DDR. CONCLUSION: These findings reveal that diminution in circulating Retn reduced myocardial fibrosis and apoptosis, and improved heart function in a mouse model of HF, at least in part, through attenuation of miR148b-3p and DDR. The results of this study indicate that controlling Retn levels may provide a potential therapeutic approach for treating pressure overload-induced HF.


Assuntos
Dano ao DNA , Insuficiência Cardíaca , Resistina , Animais , Modelos Animais de Doenças , Fibrose , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Resistina/genética , Resistina/metabolismo , Remodelação Ventricular
14.
Org Lett ; 23(24): 9574-9579, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34854691

RESUMO

Five-carbon (C5) structural units are the fundamental building blocks of many natural products. An unprecedented palladium-catalyzed three-component dehydrogenative cascade coupling of indoles, 2-methylbut-2-ene, and carboxylic acids has been developed. The approach enables the straightforward introduction of a C3'-bonded five-carbon structural unit with a tertiary alcohol quaternary carbon center into indoles. The protocol employs 2-methylbut-2-ene as the C5 source and is featured by a broad substrate scope, atom and step economies, and high chemo- and regioselectivies.

15.
Front Genet ; 12: 762136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707644

RESUMO

Diabetic mellitus erectile dysfunction (DMED) is one of the most common complications of diabetes mellitus (DM), which seriously affects the self-esteem and quality of life of diabetics. MicroRNAs (miRNAs) are endogenous non-coding RNAs whose expression levels can affect multiple cellular processes. Many pieces of studies have demonstrated that miRNA plays a role in the occurrence and development of DMED. However, the exact mechanism of this process is unclear. Hence, we apply miRNA sequencing from blood samples of 10 DMED patients and 10 DM controls to study the mechanisms of miRNA interactions in DMED patients. Firstly, we found four characteristic miRNAs as signature by the SVM-RFE method (hsa-let-7E-5p, hsa-miR-30 days-5p, hsa-miR-199b-5p, and hsa-miR-342-3p), called DMEDSig-4. Subsequently, we correlated DMEDSig-4 with clinical factors and further verified the ability of these miRNAs to classify samples. Finally, we functionally verified the relationship between DMEDSig-4 and DMED by pathway enrichment analysis of miRNA and its target genes. In brief, our study found four key miRNAs, which may be the key influencing factors of DMED. Meanwhile, the DMEDSig-4 could help in the development of new therapies for DMED.

16.
Org Lett ; 23(4): 1216-1221, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33528267

RESUMO

An efficient and unprecedented strategy for the synthesis of 1,4-enediones from saturated ketones has been developed via palladium-catalyzed oxidative dehydrogenation. The protocol employs molecular oxygen as the sole oxidant and represents an atom- and step-economic process. The approach showed broad substrate scope, good functional group tolerance, and complete E-stereoselectivity. The reaction mechanism has been investigated through deuterium-labeling experiments and intermediate experiments.

17.
Pharmacol Res ; 167: 105414, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33524540

RESUMO

Cardiac fibrosis is characterized by excessive deposition of extracellular matrix proteins and myofibroblast differentiation. Our previous findings have implicated resistin in cardiac fibrosis; however, the molecular mechanisms underlying this process are still unclear. Here we investigated the role of resistin in fibroblast-to-myofibroblast differentiation and elucidated the pathways involved in this process. Fibroblast-to-myofibroblast transdifferentiation was induced with resistin or TGFß1 in NIH-3T3 and adult cardiac fibroblasts. mRNA and protein expression of fibrotic markers were analyzed by qPCR and immunoblotting. Resistin-knockout mice, challenged with a high-fat diet (HFD) for 20 weeks to stimulate cardiac impairment, were analyzed for cardiac function and fibrosis using histologic and molecular methods. Cardiac fibroblasts stimulated with resistin displayed increased fibroblast-to-myofibroblast conversion, with increased levels of αSma, col1a1, Fn, Ccn2 and Mmp9, with remarkable differences in the actin network appearance. Mechanistically, resistin promotes fibroblast-to-myofibroblast transdifferentiation and fibrogenesis via JAK2/STAT3 and JNK/c-Jun signaling pathways, independent of TGFß1. Resistin-null mice challenged with HFD showed an improvement in cardiac function and a decrease in tissue fibrosis and reduced mRNA levels of fibrogenic markers. These findings are the first to delineate the role of resistin in the process of cardiac fibroblast-to-myofibroblast differentiation via JAK/STAT3 and JNK/c-Jun pathways, potentially leading to stimulation of cardiac fibrosis.


Assuntos
Transdiferenciação Celular/fisiologia , Fibroblastos/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Miócitos Cardíacos/metabolismo , Resistina/farmacologia , Fator de Transcrição STAT3/metabolismo , Animais , Transdiferenciação Celular/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Células HEK293 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Janus Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/efeitos dos fármacos , Células NIH 3T3 , Resistina/deficiência
18.
Opt Express ; 27(16): 22393-22407, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510534

RESUMO

High-power fiber lasers have been widely explored in engineering and science, and improving the beam quality restricted by transverse mode instability (TMI) is waiting to be solved for extra high-power applications. Here, we theoretically propose a phase transition model for understanding TMI in a fiber oscillator. A general dynamics model describing TMI is established by modifying the heat equation, and then a special dynamics model of a two-mode fiber (TMF) oscillator is obtained by applying this general dynamics model to TMF oscillator case. Theoretical analysis shows that there is a reversible phase transition point in this TMF oscillator model, which can well explain the sudden and reversible change of TMI. Based on linear stability analysis near the phase transition point, an analytical threshold formula of TMI is given to calculate the TMI threshold in the TMF oscillator. The calculated results are consistent with the reported experimental results. Furthermore, the relationship between the TMI threshold and several parameters was also discussed in detail such as laser wavelength, pump wavelength, core radius, cladding radius, etc. This theoretical model will be useful to understand and suppress the TMI in fiber oscillators.

19.
Appl Opt ; 57(27): 7943-7949, 2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30462065

RESUMO

By applying an optimized chelate gas phase deposition technique, a Yb/Ce codoped aluminosilicate fiber with ultra-low loss of 1.55 dB/km was successfully fabricated and reported. The fiber showed homogenous distribution of the refractive index and dopant concentration devoid of central dip and clustering. Using the fiber as the amplifier stage, it delivered 1023 W near-single-mode laser output (M2=1.35) with a high slope efficiency of 85.1%, and the fiber temperature was less than 24.2°C, primarily benefiting from the ultra-low background loss. The fiber also exhibited low photodarkening-induced loss, illustrating its outstanding photodarkening resistance. These results indicate that the ultra-low-loss Yb/Ce codoped aluminosilicate fiber is a prospective candidate for stable and reliable fiber laser applications.

20.
J Cell Mol Med ; 18(5): 780-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24655344

RESUMO

The midterm effects of cardiac telocytes (CTs) transplantation on myocardial infarction (MI) and the cellular mechanisms involved in the beneficial effects of CTs transplantation are not understood. In the present study, we have revealed that transplantation of CTs was able to significantly decrease the infarct size and improved cardiac function 14 weeks after MI. It has established that CT transplantation exerted a protective effect on the myocardium and this was maintained for at least 14 weeks. The cellular mechanism behind this beneficial effect on MI was partially attributed to increased cardiac angiogenesis, improved reconstruction of the CT network and decreased myocardial fibrosis. These combined effects decreased the infarct size, improved the reconstruction of the LV and enhanced myocardial function in MI. Our findings suggest that CTs could be considered as a potential cell source for therapeutic use to improve cardiac repair and function following MI, used either alone or in tandem with stem cells.


Assuntos
Células Intersticiais de Cajal/transplante , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Miocárdio/patologia , Animais , Antígenos CD34/metabolismo , Colágeno/metabolismo , Feminino , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Infarto do Miocárdio/patologia , Neovascularização Fisiológica , Proteínas Proto-Oncogênicas c-kit/metabolismo , Ratos Sprague-Dawley , Transplante de Células-Tronco
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