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1.
Chembiochem ; 24(19): e202300424, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37470220

RESUMO

Co-delivery of anticancer drugs and target agents by endogenous materials is an inevitable approach towards targeted and synergistic therapy. Employing DNA base pair complementarities, DNA nanotechnology exploits a unique nanostructuring method and has demonstrated its capacity for nanoscale positioning and templated assembly. Moreover, the water solubility, biocompatibility, and modifiability render DNA structure suitable candidate for drug delivery applications. We here report single-stranded DNA tail conjugated antitumor drug paclitaxel (PTX), and the co-delivery of PTX, doxorubicin and targeting agent mucin 1 (MUC-1) aptamer on a DNA nanobarrel carrier. We investigated the effect of tail lengths on drug release efficiencies and dual drug codelivery-enabled cytotoxicity. Owing to the rapidly developing field of structural DNA nanotechnology, functional DNA-based drug delivery is promising to achieve clinical therapeutic applications.


Assuntos
Antineoplásicos , Nanopartículas , Paclitaxel/farmacologia , Paclitaxel/química , Sistemas de Liberação de Medicamentos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Doxorrubicina , Liberação Controlada de Fármacos , DNA , Portadores de Fármacos/química , Linhagem Celular Tumoral , Nanopartículas/química
2.
Molecules ; 28(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771107

RESUMO

We herein report the acid/base-steered two distinct reaction pathways of 2-acylbenzoic acids with isatoic anhydrides. In the presence of Na2CO3, the cascade process consists of the cyclization of 2-acetylbenzoic acid and nucleophilic ring-opening reaction of isatoic anhydride to furnish isobenzofuranone derivatives with high efficiency. However, p-toluenesulfonic acid can promote the product isobenzofuranones to undergo sequential intramolecular rearrangment, nucleophilic addition and cyclization reaction to produce diverse isoindolobenzoxazinones in good yields. The synthetic utility of this method was further demonstrated by the gram-scale preparation of the desired products and the facile transformations of the resulting products.

3.
J Org Chem ; 87(15): 9769-9781, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35866754

RESUMO

Different Lewis acid promotor-steered highly regioselective phosphorylation of tertiary enamides with diverse H-phosphonates or H-phosphine oxides was developed. Under the catalysis of iron salt, the phosphonyl group was introduced into the α-position of tertiary enamides, affording various α-phosphorylated amides in high efficiency. On the other hand, the ß-phosphorylated tertiary enamides were efficiently obtained as the products in the presence of manganese(III) acetylacetonate.


Assuntos
Amidas , Ácidos de Lewis , Catálise , Estrutura Molecular , Fosforilação
4.
J Org Chem ; 87(5): 3014-3024, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35073080

RESUMO

An efficient Au(I)-catalyzed intramolecular cascade reaction of tertiary enamides tethered an alkynyl group has been developed. The process is composed of a propargyl-claisen rearrangement and 5-exo-dig cyclization. This protocol provided a powerful method for the preparation of a variety of pentasubstituted pyrroles derivatives with excellent functional group tolerance in excellent yields. Scale-up experiment and chemical transformations of products exhibited the versatility of tertiary enamides in organic synthesis again.


Assuntos
Ouro , Pirróis , Catálise , Ciclização , Ouro/química , Estrutura Molecular , Pirróis/química
5.
Org Biomol Chem ; 20(28): 5566-5574, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35792054

RESUMO

A concise manganese(III)-promoted stereoselective ß-phosphorylation of acyclic tertiary enamides and diverse H-phosphine oxides was achieved. This reaction proceeds with absolute E-selectivity in contrast to Z-selectivity obtained in other previous works and affords various E-selective ß-phosphorylated tertiary enamides in high efficiency. To the best of our knowledge, this is the first case of E-selective ß-phosphorylation of tertiary enamides through C-H functionalization. In addition, the method features broad substrate scope, good functional group compatibility and efficient scale-up.


Assuntos
Amidas , Manganês , Humanos , Estrutura Molecular , Fosforilação , Estereoisomerismo
6.
Org Biomol Chem ; 19(37): 8086-8095, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34476428

RESUMO

An exquisite metal-free cascade cyclization reaction of 2-acylbenzoic acids with amines was developed, which provided a powerful method for the one-pot synthesis of diverse isoindoloisoquinoline and benzoindolizinoindole derivatives. This protocol avoided the use of metal catalysts, proceeded with high efficiency and had broad substrate scope. These resulting products could be transformed into tertiary amines under the reduction of LiAlH4/AlCl3, followed by the Hofmann elimination offering lots of nitrogen-containing nine-membered ring compounds in excellent yields. All synthesized products containing fused N-polycyclic skeletons were difficult to be constructed using traditional methods and they have a wide range of applications in the pharmaceutical area.


Assuntos
Aminas
7.
Angew Chem Int Ed Engl ; 55(11): 3799-803, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26880262

RESUMO

Reported is a new and efficient strategy for rapid construction of the chiral tetrahydropyrrolo[2,1-a]isoquinolin-3(2H)-one structure from unique tertiary enamide synthons. A Cu(OTf)2 /chiral Pybox complex catalyzes the intramolecular enantioselective addition of tertiary enamides to ketonic carbonyls with subsequent diastereoselective interception of the resulting acyliminium by tethered electron-rich aryl moiety. The tandem reaction produces diverse tetrahydropyrrolo[2,1-a]isoquinolin-3(2H)-one derivatives as the sole diastereoisomers in good to excellent yields with up to 98.5 % ee. The transformations of the resulting heterocycles into various hexahydropyrrolo[2,1-a]isoquinoline derivatives were also demonstrated. The cyclization products, which are difficult to obtain by other synthetic means, are structural motifs found in many bioactive alkaloids.


Assuntos
Alcaloides/síntese química , Amidas/química , Isoquinolinas/síntese química , Pirróis/síntese química , Catálise
8.
Sci Rep ; 14(1): 686, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38182722

RESUMO

High altitude exposure increases the risk of myocardial ischemia (MI) and subsequent cardiovascular death. Machine learning techniques have been used to develop cardiovascular disease prediction models, but no reports exist for high altitude induced myocardial ischemia. Our objective was to establish a machine learning-based MI prediction model and identify key risk factors. Using a prospective cohort study, a predictive model was developed and validated for high-altitude MI. We consolidated the health examination and self-reported electronic questionnaire data (collected between January and June 2022 in 920th Joint Logistic Support Force Hospital of china) of soldiers undergoing high-altitude training, along with the health examination and second self-reported electronic questionnaire data (collected between December 2022 and January 2023) subsequent to their completion on the plateau, into a unified dataset. Participants were subsequently allocated to either the training or test dataset in a 3:1 ratio using random assignment. A predictive model based on clinical features, physical examination, and laboratory results was designed using the training dataset, and the model's performance was evaluated using the area under the receiver operating characteristic curve score (AUC) in the test dataset. Using the training dataset (n = 2141), we developed a myocardial ischemia prediction model with high accuracy (AUC = 0.86) when validated on the test dataset (n = 714). The model was based on five laboratory results: Eosinophils percentage (Eos.Per), Globulin (G), Ca, Glucose (GLU), and Aspartate aminotransferase (AST). Our concise and accurate high-altitude myocardial ischemia incidence prediction model, based on five laboratory results, may be used to identify risks in advance and help individuals and groups prepare before entering high-altitude areas. Further external validation, including female and different age groups, is necessary.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Feminino , Humanos , Estudos de Coortes , Altitude , Estudos Prospectivos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiologia , Aprendizado de Máquina
9.
BMC Musculoskelet Disord ; 12: 76, 2011 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-21492461

RESUMO

BACKGROUND: Exposure of the anterior or lateral lumbar via the retroperitoneal approach easily causes injuries to the lumbar plexus. Lumbar plexus injuries which occur during anterior or transpsoas lumbar spine exposure and placement of instruments have been reported. This study aims is to provide more anatomical data and surgical landmarks in operations concerning the lumbar plexus in order to prevent lumbar plexus injuries and to increase the possibility of safety in anterior approach lumbar surgery. METHODS: To study the applied anatomy related to the lumbar plexus of fifteen formaldehyde-preserved cadavers, Five sets of Virtual Human (VH) data set were prepared and used in the study. Three-dimensional (3D) computerized reconstructions of the lumbar plexus and their adjacent structures were conducted from the VH female data set. RESULTS: The order of lumbar nerves is regular. From the anterior view, lumbar plexus nerves are arranged from medial at L5 to lateral at L2. From the lateral view, lumbar nerves are arranged from ventral at L2 to dorsal at L5. The angle of each nerve root exiting outward to the corresponding intervertebral foramen increases from L1 to L5. The lumbar plexus nerves are observed to be in close contact with transverse processes (TP). All parts of the lumbar plexus were located by sectional anatomy in the dorsal third of the psoas muscle. Thus, access to the psoas major muscle at the ventral 2/3 region can safely prevent nerve injuries. 3D reconstruction of the lumbar plexus based on VCH data can clearly show the relationships between the lumbar plexus and the blood vessels, vertebral body, kidney, and psoas muscle. CONCLUSION: The psoas muscle can be considered as a surgical landmark since incision at the ventral 2/3 of the region can prevent lumbar plexus injuries for procedures requiring exposure of the lateral anterior of the lumbar. The transverse process can be considered as a landmark and reference in surgical operations by its relative position to the lumbar plexus. 3D reconstructions of the lumbar plexus based on VCH data provide a virtual morphological basis for anterior lumbar surgery.


Assuntos
Gráficos por Computador , Simulação por Computador , Imageamento Tridimensional , Vértebras Lombares/inervação , Plexo Lombossacral/anatomia & histologia , Modelos Anatômicos , Raízes Nervosas Espinhais/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Artroplastia/efeitos adversos , Cadáver , Feminino , Humanos , Vértebras Lombares/irrigação sanguínea , Vértebras Lombares/cirurgia , Plexo Lombossacral/lesões , Masculino , Pessoa de Meia-Idade , Músculos Psoas/anatomia & histologia , Fusão Vertebral/efeitos adversos , Raízes Nervosas Espinhais/lesões
10.
Org Lett ; 22(22): 8814-8818, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33176425

RESUMO

An exquisite protocol to the synthesis of erythrina-related structural derivatives was developed, which is composed of a nucleophilic addition of tertiary enamides to ketonic carbonyls and the trapping of acyliminium by an aromatic unit. This protocol afforded a powerful method for the construction of diverse fused N-pentacyclic skeletons in high efficiency and excellent diastereoselectivity by just using different acid catalysts.

11.
PLoS One ; 9(12): e113133, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25551618

RESUMO

Infection by methicillin-resistant Staphylococcus aureus (MRSA) is a life-threatening condition, and formation of biofilms can lead to treatment failure in a clinical setting. The aim of this study was to demonstrate the in vivo bactericidal effects of a combination of vancomycin (VAN) and fosfomycin (FOS) against MRSA in a rat carboxymethyl cellulose-pouch biofilm model. The results of the time-kill assay showed that the combination therapy was capable of killing at low minimal inhibitory concentrations (MIC) (½ × MIC VAN +1 × MIC FOS and 1 × MIC VAN + 1 × MIC FOS). In the in vivo study, a synergistically bactericidal effect was observed when using the combination therapy on MRSA embedded in the mature biofilm model. In comparison with the untreated control group and the groups receiving either VAN or FOS alone, the rats treated with combination therapy had lower MRSA colony counts in exudates from the pouch, lower white blood cell and neutrophil counts, and C-reactive protein (CRP) in peripheral blood. Furthermore, histological analysis of the pouch wall indicated combination therapy resulted in disappearance of biofilm-like structures, marked decrease in necrosis, and formation of granular tissue. In conclusion, the combination of VAN with FOS had a synergistic bactericidal effect on chronic MRSA infection embedded in biofilm, providing an alternative approach to treating this condition.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Fosfomicina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Vancomicina/farmacologia , Animais , Antibacterianos/uso terapêutico , Proteína C-Reativa/metabolismo , Sinergismo Farmacológico , Fosfomicina/uso terapêutico , Contagem de Leucócitos , Masculino , Testes de Sensibilidade Microbiana , Ratos , Ratos Sprague-Dawley , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/uso terapêutico
12.
Mol Biotechnol ; 55(2): 111-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23636934

RESUMO

Induced multipotent stem (iMS) cells are originated from somatic cells and become multipotent by genetic and/or epigenetic modifications. Previous studies have shown that the fish oocytes extracts (FOE) can induce skin fibroblast cells into iMS cells. In this study, we aim to determine whether FOE can similarly induce mouse peripheral blood mononuclear cells (PBMCs) into the iMS state and if so, whether they can survive longer when they are transplanted into the irradiation female mice. PBMCs of GFP-transgenic male mice were cultured and transiently reprogrammed by FOE. They were deemed reaching the iMS state after detection of expression of stem cell markers. The iMS-like PBMCs were transplanted into female C57BL mice by tail vein injection. The spleen wet weights as well as numbers of colonies of the recipient mice were examined. The results showed the spleen wet weights and numbers of spleen colonies of FOE-induced group were all significantly higher than those of the non-induced group and negative control group. On day 90 after transplantation, FISH analysis detected the presence of Y chromosome in the induced group, but not of the other groups. The current findings demonstrate that FOE-induced PBMCs are able to survive longer in irradiated female mice.


Assuntos
Reprogramação Celular/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Células-Tronco Pluripotentes Induzidas/transplante , Leucócitos Mononucleares/fisiologia , Oócitos , Animais , Sobrevivência Celular , Células Cultivadas , Feminino , Peixes , Hibridização in Situ Fluorescente , Leucócitos Mononucleares/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Baço/metabolismo , Irradiação Corporal Total , Cromossomo Y
13.
PLoS One ; 8(12): e83507, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367598

RESUMO

INTRODUCTION: Renal interstitial fibrosis (RIF) is a significant cause of end-stage renal failure. The goal of this study was to characterize the distribution of transplanted induced autologous stem cells in a rabbit model of renal interstitial fibrosis and evaluate its therapeutic efficacy for treatment of renal interstitial fibrosis. METHODS: A rabbit model of renal interstitial fibrosis was established. Autologous fibroblasts were cultured, induced and labeled with green fluorescent protein (GFP). These labeled stem cells were transplanted into the renal artery of model animals at 8 weeks. RESULTS: Eight weeks following transplantation of induced autologous stem cells, significant reductions (P < 0.05) were observed in serum creatinine (SCr) (14.8 ± 1.9 mmol/L to 10.1 ± 2.1 mmol/L) and blood urea nitrogen (BUN) (119 ± 22 µmol/L to 97 ± 13 µmol/L), indicating improvement in renal function. CONCLUSIONS: We successfully established a rabbit model of renal interstitial fibrosis and demonstrated that transplantation of induced autologous stem cells can repair kidney damage within 8 weeks. The repair occurred by both inhibition of further development of renal interstitial fibrosis and partial reversal of pre-existing renal interstitial fibrosis. These beneficial effects lead to the development of normal tissue structure and improved renal function.


Assuntos
Células-Tronco Pluripotentes Induzidas/transplante , Nefrite Intersticial/terapia , Transplante de Células-Tronco , Animais , Diferenciação Celular , Fibroblastos/citologia , Fibrose , Rim/diagnóstico por imagem , Rim/metabolismo , Rim/patologia , Nefrite Intersticial/diagnóstico por imagem , Nefrite Intersticial/metabolismo , Nefrite Intersticial/patologia , Tamanho do Órgão , Coelhos , Tomografia Computadorizada de Emissão de Fóton Único , Fator de Crescimento Transformador beta1/metabolismo , Transplante Autólogo
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