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1.
J Med Educ Curric Dev ; 11: 23821205241226818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38532855

RESUMO

Objective: To evaluate the effect of the uncertainty training on improvement of students' diagnostic ability. Methods: Data were collected on 70 fifth-year medical students enrolled in the Case Discussion courses on Obstetrics and Gynecology in the spring of 2020. Of these students, 36 were in the uncertainty training group and 34 in the control group. The effect of training was evaluated by cognitively diagnostic assessment which mapped exam questions to 4 attributes assessing clinical reasoning and basic science knowledge. Results: Uncertainty training was able to improve students' ability to use basic science concepts for inference and problem solving, and the ability to integrate complex clinical information to arrive at a diagnosis. But it could not improve students' ability on the basic recall of foundational concepts and the ability to use basic science concepts in clinical reasoning. Medical students could do well in integrating complex clinical information although they didn't recall basic science knowledge well. Conclusion: Uncertainty training could be used as an effective teaching method in Case Discussion course on Obstetrics and Gynecology. However, students still need to improve their basic knowledge besides the training.

2.
J Am Chem Soc ; 146(12): 7971-7978, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38483538

RESUMO

We describe a nickel-catalyzed carbonylative cross-coupling of unactivated secondary alkyl electrophiles with the organozinc reagent at atmospheric CO gas, thus allowing the expedient construction of unsymmetric dialkyl ketones with broad functional group tolerance. The leverage of a newly developed NN2-pincer type ligand enables the chemoselective three-component carbonylation by overcoming the competing Negishi coupling, the undesired ß-hydride elimination, and dehalogenation of alkyl iodides side pathways. Both alkyl iodides and alkyl tosylates are compatible in the single electron transfer involved mechanism.

3.
Angew Chem Int Ed Engl ; 63(7): e202316012, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38164694

RESUMO

Chromium-catalyzed enantioselective Nozaki-Hiyama-Kishi (NHK) reaction represents one of the most powerful approaches for the formation of chiral carbon-heteroatom bond. However, the construction of sterically encumbered tetrasubstituted stereocenter through NHK reaction still posts a significant challenge. Herein, we disclose a cobalt-catalyzed aza-NHK reaction of ketimine with alkenyl halide to provide a convenient synthetic approach for the manufacture of enantioenriched tetrasubstituted α-vinylic amino acid. This protocol exhibits excellent functional group tolerance with excellent 99 % ee in most cases. Additionally, this asymmetric reductive method is also applicable to the aldimine to access the trisubstituted stereogenic centers.

4.
Angew Chem Int Ed Engl ; : e202318991, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252658

RESUMO

ß-Tertiary amino acid derivatives constitute one of the most frequently occurring units in natural products and bioactive molecules. However, the efficient asymmetric synthesis of this motif still remains a significant challenge. Herein, we disclose a cobalt-catalyzed enantioselective reductive addition reaction of ketimine using α-chloro carbonyl compound as a radical precursor, providing expedient access to a diverse array of enantioenriched ß-quaternary amino acid analogues. This protocol exhibits outstanding enantioselectivity and broad substrate scope with excellent functional group tolerance. Preliminary mechanism studies rule out the possibility of Reformatsky-type addition and confirm the involvement of radical species in stereoselective addition process. The synthetic utility has been demonstrated through the rapid assembly of iterative amino acid units and oligopeptide, showcasing its versatile platform for late-stage modification of drug candidates.

5.
Nat Chem ; 16(3): 398-407, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38082178

RESUMO

Unnatural chiral α-tertiary amino acids containing two different carbon-based substituents at the α-carbon centre are widespread in biologically active molecules. This sterically rigid scaffold is becoming a growing research interest in drug discovery. However, a robust protocol for chiral α-tertiary amino acid synthesis remains scarce due to the challenge of stereoselectively constructing sterically encumbered tetrasubstituted stereogenic carbon centres. Herein we report a cobalt-catalysed enantioselective aza-Barbier reaction of ketimines with various unactivated alkyl halides, including alkyl iodides, alkyl bromides and alkyl chlorides, enabling the formation of chiral α-tertiary amino esters with a high level of enantioselectivity and excellent functional group tolerance. Primary, secondary and tertiary organoelectrophiles are all tolerated in this asymmetric reductive addition protocol, which provides a complementary method for the well-exploited enantioselective nucleophilic addition with moisture- and air-sensitive organometallic reagents. Moreover, the three-component transformation of α-ketoester, amine and alkyl halide represents a formal asymmetric deoxygenative alkylamination of the carbonyl group.

6.
Nat Commun ; 14(1): 6960, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907542

RESUMO

Transition metal-catalyzed carbonylative reaction with CO gas are among the central task in organic synthesis, enabling the construction of highly valuable carbonyl compound. Here, we show an earth-abundant nickel-catalyzed three-component tandem acylzincation/cyclization sequence of allene and alkylzinc reagent with 1 atm of CO under mild conditions. This protocol is featured by broad functional group tolerance with high reaction selectivity, providing a rapid and convenient synthetic method for the construction of diverse fully substituted benzotropone derivatives. Mechanistic studies reveal that the installation of a cyano group tethered to allene moiety enables the high regio- and stereoselectivity of this acylzincation of allene, allowing the selective formation of three consecutive C-C bonds in a highly efficient manner.

7.
Chem Asian J ; 18(1): e202201061, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36373896

RESUMO

Reported here is a nickel-catalyzed aminocarbonylation of aromatic iodides with (hetero)aryl anilines and alkyl amines under atmospheric CO pressure. The reaction features with broad substrate scope with excellent functional group tolerance, providing an expedient method for the construction of amide analogues. Notably, amino alcohols can be selectively transformed into the corresponding amides successfully without interfering the hydroxyl group under the current standard conditions.


Assuntos
Iodetos , Níquel , Catálise , Amidas , Aminas
8.
Biomedicines ; 10(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36551866

RESUMO

Endometriosis is a chronic inflammatory disease with an uncertain pathogenesis. Peritoneal immune dysregulation plays an important role in the pathogenesis of endometriosis. Exosomes are messengers of intercellular communication. This study mainly investigated the role of exosomes from the uterine cavity in endometriosis. Exosomes of the uterine aspirate fluid were isolated and cocultured with macrophages for 48 h. Flow cytometry was used to detect macrophage polarization. A Human MAPK Phosphorylation Antibody Array and Western blot were used to detect the phosphorylation of the MAPK pathway. A microRNA sequencing analysis was used to detect differentially expressed miRNAs. Our research found that exosomes of the uterine aspirate fluid from endometriosis could reduce the proportion of CD80+ macrophages. Additionally, it could inhibit the expression of P-JNK in macrophages. However, the JNK activator anisomycin could increase the proportion of CD80+ macrophages. In addition, exosomes of the uterine aspirate fluid from endometriosis could promote the migration and invasion of endometrial stromal cells by acting on macrophages. The expression of miR-210-3p was increased in both exosomes and the eutopic endometrium in patients with endometriosis through miRNA sequencing, which could also reduce the proportion of CD80+ macrophages. In summary, we propose that exosomes from the uterine cavity in patients with endometriosis may affect the phenotype of macrophages by inhibiting the JNK signaling pathway, thus mediating the formation of an immunological microenvironment conducive to the development of endometriosis.

9.
Nat Commun ; 13(1): 5964, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36216794

RESUMO

Nitrogen-based heterocycles have aroused widespread interest due to their reoccurrence in many pharmaceuticals. Amongst these motifs, the enantioenriched lactams are the ubiquitous scaffolds found in myriad biologically active natural products and drugs. Recently, the transition metal-catalyzed asymmetric carbamoylation has been widely employed as a straightforward arsenal for chiral lactam architecture synthesis, including ß-lactam and γ-lactam. However, despite the extensive efforts, there still remains no protocol to accomplish the related δ-lactam synthesis. In this manuscript, the Ni-catalyzed enantioselective carbamoylation of unactivated alkenes by the leverage of reductive dicarbofunctionalization strategy allows for the expedient access to two types of mostly common six-membered lactams: 3,4-dihydroquinolinones and 2-piperidinone in high yield and enantioselectivity. This protocol features with good functional group tolerance, as well as broad substrate scope. The newly developed chiral 8-Quinox skeleton ligand is the key parameter for this transformation, which significantly enhances the reactivity and enantioselectivity.


Assuntos
Alcenos , Produtos Biológicos , Catálise , Lactamas , Ligantes , Estrutura Molecular , Nitrogênio , Preparações Farmacêuticas , Carbamilação de Proteínas , Estereoisomerismo , beta-Lactamas
10.
Angew Chem Int Ed Engl ; 61(38): e202210484, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35894840

RESUMO

A nickel-catalyzed three-component carbonylative cross-coupling reaction of allylic alcohols and organoalanes with CO at atmospheric pressure is reported, enabling the expedient formation of ß,γ-unsaturated ketones with broad scope. Particularly, the chemoselective allylic carbonylation of diols further highlights the practicability of this protocol. The leverage of organoalanes as both the coupling components and the activators for the alcohol functionalization is crucial for this method, thus no extraneous activators are required.

11.
Chem Commun (Camb) ; 58(66): 9282-9285, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35904065

RESUMO

The construction of vicinal stereogenic centers via the simultaneous formation of two C-C bonds across alkenes under oxidative conditions is a stubborn challenge. Herein, we report a Pd(II)-catalyzed highly enantioselective intermolecular oxidative 1,2-diarylation reaction of internal enamides with aryl boronic acids, enabling the expedient construction of two vicinal stereocenters with excellent diastereo-, and enantioselectivities.


Assuntos
Estresse Oxidativo , Paládio , Catálise , Estrutura Molecular , Paládio/química , Estereoisomerismo
12.
Angew Chem Int Ed Engl ; 61(36): e202207536, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35818326

RESUMO

Herein, we leverage the Ni-catalyzed enantioselective reductive dicarbofunctionalization of internal alkenes with alkyl iodides to enable the synthesis of chiral pyrrolidinones bearing vicinal stereogenic centers. The application of newly developed 1-Nap Quinim is critical for formation of two contiguous stereocenters in high yield, enantioselectivity, and diastereoselectivity. This catalytic system also improves both the yield and enantioselectivity in the synthesis of α,α-dialkylated γ-lactams. Computational studies reveal that the enantiodetermining step proceeds with a carbamoyl-NiI intermediate that is reduced by the Mn reductant prior to intramolecular migratory insertion. The presence of the t-butyl group of the Quinim ligand leads to an unfavorable distortion of the substrate in the TS that leads to the minor enantiomer. Calculations also support an improvement in enantioselectivity with 1-Nap Quinim compared to p-tol Quinim.


Assuntos
Alcenos , Níquel , Alcenos/química , Catálise , Estrutura Molecular , Níquel/química , Carbamilação de Proteínas , Estereoisomerismo
13.
Org Lett ; 24(14): 2699-2704, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35389666

RESUMO

Herein, we reported a Ni-catalyzed carbonylation of cyclopropanol with benzyl bromide to afford multisubstituted cyclopentenone under 1 atm of CO. The reaction proceeds through cascade carbonylation of benzyl bromides, followed by generation of nickel homoenolate from cyclopropanols via ß-C elimination to afford 1,4-diketones, which undergoes intramolecular Aldol condensation to furnish highly substituted cyclopentenone derivatives in moderate to good yields. The reaction exhibits high functional group tolerance with broad substrate scope.

14.
BMC Genom Data ; 23(1): 20, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303800

RESUMO

BACKGROUND: This study explored the key genes related to immune cell infiltration in endometriosis. RESULTS: The Gene Expression Omnibus (GEO) datasets (GSE7305, GSE7307, and GSE11691), containing a total of 37 endometriosis and 42 normal tissues, were retrieved and analyzed to determine the differentially expressed genes (DEGs). Gene ontology (GO) annotations and Kyoto Encyclopedia of Genes (KEGG) analysis were performed to identify the pathways that were significantly enriched. The xCell software was used to analyze immune cell infiltration and correlation analyses were performed to uncover the relationship between key genes and immune cells. The analysis identified 1031 DEGs (581 upregulated and 450 downregulated DEGs), while GO analysis revealed altered extracellular matrix organization, collagen-containing extracellular matrix, and glycosaminoglycan binding and KEGG enrichment showed genes related to metabolic pathways, pathways in cancer, phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) signaling, proteoglycans in cancer, and the mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, the protein-protein interaction network revealed 10 hub genes, i.e., IL6, FN1, CDH1, CXCL8, IGF1, CDK1, PTPRC, CCNB1, MKI67, and ESR1. The xCell analysis identified immune cells with significant changes in all three datasets, including CD4+ and CD8+ T cells, CD8+ Tem, eosinophils, monocytes, Th1 cells, memory B-cells, activated dendritic cells (aDCs), and plasmacytoid dendritic cells (pDCs). These 10 hub genes were significantly associated with at least three types of immune cells. CONCLUSIONS: Aberrant gene expression was related to abnormal infiltration of different immune cells in endometriosis and was associated with endometriosis development by affecting the tissue microenvironment and growth of ectopic endometrial cells.


Assuntos
Endometriose , Perfilação da Expressão Gênica , Linfócitos T CD8-Positivos , Biologia Computacional , Endometriose/genética , Feminino , Humanos , Fosfatidilinositol 3-Quinases/genética
15.
Chem Commun (Camb) ; 58(29): 4643-4646, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35311870

RESUMO

A nickel-catalyzed alkoxycarbonylation of aromatic iodides with alcohols under atmospheric pressure of carbon monoxide is presented here. This operationally simple protocol allows the facile synthesis of (hetero)aromatic esters, exhibiting broad substrate scope with excellent functional group tolerance. Various primary and secondary aliphatic alcohols as well as phenols are suitable for this transformation.

16.
Angew Chem Int Ed Engl ; 61(26): e202111598, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35286744

RESUMO

The construction of multi-stereocenters by a transition metal-catalyzed cross-coupling reaction is a major challenge. The catalytic desymmetric functionalization of unactivated alkenes remains largely unexplored. Herein, we disclose -a desymmetric dicarbofunctionalization of 1,6-dienes via a nickel-catalyzed reductive cross-coupling reaction. The leverage of the underdeveloped chiral 8-Quinox enables the Ni-catalyzed desymmetric carbamoylalkylation of both unactivated mono- and disubstituted alkenes to form pyrrolidinone bearing two nonadjacent stereogenic centers in high enantio- and stereoselectivitives with broad functional-group tolerance. The synthetic application of pyrrolidinones allows the rapid access to complex chiral fused-heterocycles.

17.
Arch Gynecol Obstet ; 305(6): 1573-1580, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34988659

RESUMO

PURPOSE: The imbalance of microbiome in vivo is believed to be involved in the pathogenicity of endometriosis. This study aimed to investigate and analyze the composition of bacterial communities in the peritoneal fluid of women with endometriosis. METHODS: To collect peritoneal fluid samples from women with (N = 36) and without (N = 25) endometriosis in a generalized hospital in Hunan, China during January to December of 2019. Genomic DNA was extracted from peritoneal fluid samples, and targeted amplified for the V4 region of 16S ribosomal RNA gene followed by amplicon sequencing. Non-parametric Wilcoxon rank-sum test and chi-squared test were used to compare and analysis the difference between groups. RESULTS: Analysis showed that microbiota diversity was similar in the peritoneal fluid of women with or without endometriosis. Ralstonia mainly dominated in the peritoneal fluid of patients in both groups, with an overall relative abundance of 11.15% (95% CI: 10.51-11.80%) in endometriosis patients, followed by Acinetobacter, Pseudomonas, Asticcacaulis, and Methyloversatilis, with no significant difference between endometriosis patients and the control group. Nevertheless, there were microbes with different abundance in peritoneal fluid of the two groups, and the relative abundance was less than 0.5%. Acidovorax (P = 0.01), Devosia (P = 0.03), Methylobacterium (P = 0.03), Phascolarctobacterium (P = 0.03), and Streptococcus (P = 0.04) were more abundant in the peritoneal fluid of endometriosis patients than the controls, while Brevundimonas (P = 0.01) and Stenotrophomonas (P = 0.04) were less abundant. CONCLUSION: The composition of minority microbiota including Acidovorax, Devosia, Methylobacterium, Phascolarctobacterium, and Streptococcus in peritoneal fluid were found to change among women with endometriosis. Further research is needed to explore the mechanisms of these microorganisms in the pathophysiology of endometriosis.


Assuntos
Endometriose , Microbiota , Líquido Ascítico , Bactérias/genética , Feminino , Humanos , Microbiota/genética , RNA Ribossômico 16S/genética
18.
Arch Gynecol Obstet ; 305(1): 117-127, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34542679

RESUMO

PURPOSE: Exosomes are vesicles secreted by cells that contain a wide variety of biomolecules, including proteins or nucleic acids. MicroRNAs (miRNAs), which are commonly found in exosomes, are known to play important roles in the pathophysiology of endometriosis. METHODS: This study investigated the miRNA expression profile of serum exosomes from women with endometriosis in comparison with normal controls as well as the possible role of identified miRNAs in the pathogenesis of endometriosis. Exosomes with a diameter between 60 and 100 nm were identified by their expression of exosomal marker proteins CD9 and CD63. RESULTS: Microarray miRNA expression profiling analysis revealed that 26 genes were significantly up-regulated and 19 genes were significantly down-regulated in serum exosomes from endometriosis patients compared with normal controls. These differentially expressed miRNAs were mainly enriched in the regulation of cellular development, metabolism, and involved in the regulation of the MAPK and PI3k-Akt pathways. qRT-PCR analysis verified the differential expression of three miRNAs, miR-26b-5p, miR-215-5p, and miR-6795-3p. CONCLUSION: Further analysis indicated that these differentially expressed miRNAs in serum exosomes may be involved in the pathogenesis of endometriosis and are related to the severity and certain symptoms of endometriosis.


Assuntos
Endometriose , Exossomos , MicroRNAs , Endometriose/diagnóstico , Endometriose/genética , Exossomos/genética , Feminino , Humanos , MicroRNAs/sangue , MicroRNAs/genética , Índice de Gravidade de Doença , Transdução de Sinais
19.
Mol Immunol ; 140: 59-69, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34655920

RESUMO

The local immune microenvironment of the uterus plays an important role in a successful pregnancy. IP-10 (CXCL10) has been extensively studied in many immune-related diseases. However, the immune role of IP-10 in early pregnancy has not been fully recognized. This study mainly investigated the role of pro-inflammatory chemokine IP-10 in pregnancy. The levels of IP-10 and its receptor chemokine receptor 3 (CXCR3) were lower in the decidual tissues of an abortion-prone mice than in normal pregnant mice. Meantime, the expression of IP-10 and CXCR3 was higher in the decidual tissues of early pregnant women than in the endometrial tissues of non-pregnant women. IP-10 promoted the production of interleukin 17 (IL-17) and interferon gamma (IFN-γ), and also promoted the migration and differentiation of uterine decidual T cells to type 1 T helper (Th1) cells and Th17 cells. The abortion rate of early pregnant mice increased but the number of CD49b+, CD11b+, and CD3ε+ cells in the decidual tissues decreased upon treatment with anti-IP-10 antibody. Moreover, anti IP-10 antibody decreased the expression of RANTES but increased the expression of anti-inflammatory cytokines IL-6 and IL-10. A successful pregnancy requires the participation of IP-10. IP-10 participates in formation of the pro-inflammatory immune microenvironment during early pregnancy by regulating the distribution of immune cells and promoting the production of pro-inflammatory cytokines.


Assuntos
Quimiocina CXCL10/metabolismo , Receptores CXCR3/metabolismo , Animais , Antígeno CD11b/metabolismo , Decídua/citologia , Feminino , Integrina alfa2/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Modelos Animais , Especificidade de Órgãos , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
20.
Exp Ther Med ; 22(3): 1003, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34345285

RESUMO

Macrophage-induced inflammation is a major factor in the pathogenesis of endometriosis. The underlying mechanisms, however, remain largely unknown. TNF-α, IL-6, IL-10 and C-C motif chemokine 20 (CCL20) levels in endometrial extracts were determined using Luminex cytokine kits. Additionally, protein arginine methyltransferase 5 (PRMT5) levels were measured using reverse transcription-quantitative PCR and western blotting. IL-6 and IP-10 levels in cells were measured using ELISA kits. In the present study, it was revealed that PRMT5 expression at both the mRNA and protein levels in THP-1-derived macrophages was significantly decreased following treatment with serum or extracts of endometrium from patients with endometriosis in the presence of lipopolysaccharide, compared with that in control cells, suggesting a possible role for macrophage-derived PRMT5 in mediating the interaction between macrophages and endometrium in endometriosis. Mechanistically, macrophage PRMT5 expression was regulated in an NF-κB-dependent and Smad2/3-independent manner, indicating that PRMT5 is a downstream target of NF-κB. Importantly, macrophage-derived PRMT5 was required for macrophage activation in endometriosis, as evidenced by the PRMT5-dependent secretion of IL-6 and IFN-γ-induced protein 10 from THP-1-derived macrophages. The present study identified NF-κB-dependent PRMT5 as a novel regulator of macrophage activation in endometriosis. Targeting PRMT5 in macrophages may be a potential therapeutic strategy against endometriosis.

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