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1.
J Am Chem Soc ; 146(12): 8508-8519, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38382542

RESUMO

Tricomponent cobalt(salen)-catalyzed carbofunctionalization of unsaturated substrates by radical-polar crossover has the potential to streamline access to broad classes of heteroatom-functionalized synthetic targets, yet the reaction platform has remained elusive, despite the well-developed analogous hydrofunctionalizations mediated by high-valent alkylcobalt intermediates. We report herein the development of a cobalt(salen) catalytic system that enables carbofunctionalization. The reaction entails a tricomponent decarboxylative 1,4-carboamination of dienes and provides a direct route to aromatic allylic amines by obviating preformed allylation reagents and protection of oxidation-sensitive aromatic amines. The catalytic system merges acridine photocatalysis with cobalt(salen)-catalyzed regioselective 1,4-carbofunctionalization that facilitates the crossover of the radical and polar phases of the tricomponent coupling process, revealing critical roles of the reactants, as well as ligand effects and the nature of the formal high-valent alkylcobalt species on the chemo- and regioselectivity.

2.
J Org Chem ; 89(12): 8734-8744, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38814709

RESUMO

A gold-catalyzed oxidative rearrangement of propargyl alcohols, derived from commercially available cyclohex-2-en-1-ones and alkynes, was successfully developed for the efficient synthesis of seven-membered rings. Thorough investigations were conducted to optimize the reaction conditions and evaluate its compatibility with various functional groups. Additionally, this methodology was applied to the formal total synthesis of guanacastepene A, demonstrating its practical utility in complex natural product synthesis. This versatile and efficient approach opens up new possibilities for the construction of diverse seven-membered ring systems, providing valuable building blocks for further exploration in drug discovery and the synthesis of intricate molecules.

3.
J Org Chem ; 89(5): 3331-3344, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363745

RESUMO

A gold(I)-catalyzed hydroamination/cycloisomerization cascade reaction was developed to yield indolizino[8,7-b]indole and indolo[2,3-a]-quinolizine derivatives from 2-ethynyltryptamides. The optimal conditions were determined by condition screening, and the functional group tolerances of these reactions were explored based on synthetic substrates. An insight into the explanation on the selectivity of the ring closure was obtained by density functional theory calculations. A plausible mechanism for the cascade reactions was proposed. Derivatization of the indolizino[8,7-b]indole and total synthesis of nauclefidine demonstrated the practicality of this strategy.

4.
Immunol Invest ; : 1-15, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814140

RESUMO

AIM: This study aimed to evaluate the miR-223-5p expression in patients with spinal cord injury (SCI) and to determine its role in the pathogenesis of SCI. METHODS: The serum miR-223-5p levels were analyzed using quantitative real-time polymerase chain reaction. The diagnostic accuracy of miR-223-5p was evaluated using the receiving operating characteristic curves. LPS-induced PC12 cells were established as an in vitro inflammatory cell model. Cell apoptosis, inflammation and oxidative stress were examined. The SCI rat model was constructed to evaluate the effects of miR-223-5p on inflammatory response and motor function in rats. RESULTS: MiR-223-5p expression was upregulated in SCI patients. MiR-223-5p expression in the complete SCI group was significantly higher than that in incomplete SCI group. ROC analysis showed that miR-223-5p can distinguish SCI patients from healthy volunteers. In vitro experiments demonstrated that LPS upregulated apoptosis and inflammation in PC12 cells. Treatment with miR-223-5p inhibitor alleviated the changes in LPS-induced PC12 cells . Inhibition of miR-223-5p can alleviate the activation of inflammatory response and the effects of SCI on the motor function in rats. CONCLUSIONS: MiR-223-5p is a potential diagnostic marker for SCI, and it can promote the SCI progression by regulating nerve cell survival, inflammation, and oxidative stress.

5.
Zygote ; 32(2): 170-174, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619002

RESUMO

Oocytes with excessively large first polar bodies (PB1) often occur in assisted reproductive procedures. Many times these oocytes are discarded without insemination and, as a result, the application of this portion of oocytes has scarcely been reported to date. Few studies have examined large PB1 oocytes in infertile women and have virtually entirely studied genetic variations for large PB1 oocyte abnormalities. Here, we describe an unusual case of a live birth from a remarkably large PB1 oocyte in a frozen embryo transfer (FET) cycle. This is the first instance of a successful live birth resulting from a PB1 oocyte with an extremely large polar body measuring 80 µM × 40 µM in size. The large PB1 oocyte was performed by an early rescue intracytoplasmic sperm injection (r-ICSI) and was formed into a blastocyst on day 5. Following FET, a healthy boy baby weighing 3100 g was finally delivered by caesarean section at 37 weeks and 5 days after conception. Additionally, there were no complications throughout the antenatal period or the perinatal phase of this following full-term delivery. In this study, it is revealed for the first time that a huge PB1 oocyte can be fertilized, resulting in the growth of a blastocyst, a subsequent pregnancy, and a live birth. This new information prompts us to reconsider the use of large PB1 oocytes. More insightful talks should be given attention to prevent the waste of embryos because not all oocytes with aberrant morphology are unavailable.


Assuntos
Transferência Embrionária , Nascido Vivo , Oócitos , Corpos Polares , Injeções de Esperma Intracitoplásmicas , Humanos , Feminino , Gravidez , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Oócitos/fisiologia , Oócitos/citologia , Masculino , Transferência Embrionária/métodos , Recém-Nascido , Blastocisto/citologia , Blastocisto/fisiologia , Criopreservação
6.
Life (Basel) ; 14(6)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38929640

RESUMO

The global prevalence of obesity is a pressing health issue, increasing the medical burden and posing significant health risks to humans. The side effects and complications associated with conventional medication and surgery have spurred the search for anti-obesity drugs from plant resources. Previous studies have suggested that Artemisiae argyi Folium (Aiye) water extracts could inhibit pancreatic lipase activities, control body weight increase, and improve the plasma lipids profile. However, the exact components and mechanisms were not precisely understood. Therefore, this research aims to identify the chemical profile of Aiye and provide a comprehensive prediction of its anti-obesity mechanisms. The water extract of Aiye was subjected to LC-MS analysis, which identified 30 phenolics. The anti-obesity mechanisms of these phenolics were then predicted, employing network pharmacology and molecular docking. Among the 30 phenolics, 21 passed the drug-likeness screening and exhibited 486 anti-obesity targets. The enrichment analysis revealed that these phenolics may combat obesity through PI3K-Akt signaling and MAPK, prolactin, and cAMP signaling pathways. Eight phenolics and seven central targets were selected for molecular docking, and 45 out of 56 docking had a binding affinity of less than -5 kcal/mol. This research has indicated the potential therapy targets and signaling pathways of Aiye in combating obesity.

7.
Comput Struct Biotechnol J ; 23: 1594-1607, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38680872

RESUMO

The high-osmolarity-sensitive protein Sho1 functions as a key membrane receptor in phytopathogenic fungi, which can sense and respond to external stimuli or stresses, and synergistically regulate diverse fungal biological processes through cellular signaling pathways. In this study, we investigated the biological functions of AaSho1 in Alternaria alternata, the causal agent of pear black spot. Targeted gene deletion revealed that AaSho1 is essential for infection structure differentiation, response to external stresses and synthesis of secondary metabolites. Compared to the wild-type (WT), the ∆AaSho1 mutant strain showed no significant difference in colony growth, morphology, conidial production and biomass accumulation. However, the mutant strain exhibited significantly reduced levels of melanin production, cellulase (CL) and ploygalacturonase (PG) activities, virulence, resistance to various exogenous stresses. Moreover, the appressorium and infection hyphae formation rates of the ∆AaSho1 mutant strain were significantly inhibited. RNA-Seq results showed that there were four branches including pheromone, cell wall stress, high osmolarity and starvation in the Mitogen-activated Protein Kinase (MAPK) cascade pathway. Furthermore, yeast two-hybrid experiments showed that AaSho1 activates the MAPK pathway via AaSte11-AaPbs2-AaHog1. These results suggest that AaSho1 of A. alternata is essential for fungal development, pathogenesis and osmotic stress response by activating the MAPK cascade pathway via Sho1-Ste11-Pbs2-Hog1.

8.
IEEE Trans Image Process ; 33: 2058-2073, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38470576

RESUMO

Existing Cross-Domain Few-Shot Learning (CDFSL) methods require access to source domain data to train a model in the pre-training phase. However, due to increasing concerns about data privacy and the desire to reduce data transmission and training costs, it is necessary to develop a CDFSL solution without accessing source data. For this reason, this paper explores a Source-Free CDFSL (SF-CDFSL) problem, in which CDFSL is addressed through the use of existing pretrained models instead of training a model with source data, avoiding accessing source data. However, due to the lack of source data, we face two key challenges: effectively tackling CDFSL with limited labeled target samples, and the impossibility of addressing domain disparities by aligning source and target domain distributions. This paper proposes an Enhanced Information Maximization with Distance-Aware Contrastive Learning (IM-DCL) method to address these challenges. Firstly, we introduce the transductive mechanism for learning the query set. Secondly, information maximization (IM) is explored to map target samples into both individual certainty and global diversity predictions, helping the source model better fit the target data distribution. However, IM fails to learn the decision boundary of the target task. This motivates us to introduce a novel approach called Distance-Aware Contrastive Learning (DCL), in which we consider the entire feature set as both positive and negative sets, akin to Schrödinger's concept of a dual state. Instead of a rigid separation between positive and negative sets, we employ a weighted distance calculation among features to establish a soft classification of the positive and negative sets for the entire feature set. We explore three types of negative weights to enhance the performance of CDFSL. Furthermore, we address issues related to IM by incorporating contrastive constraints between object features and their corresponding positive and negative sets. Evaluations of the 4 datasets in the BSCD-FSL benchmark indicate that the proposed IM-DCL, without accessing the source domain, demonstrates superiority over existing methods, especially in the distant domain task. Additionally, the ablation study and performance analysis confirmed the ability of IM-DCL to handle SF-CDFSL. The code will be made public at https://github.com/xuhuali-mxj/IM-DCL.

9.
Phytomedicine ; 126: 155426, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367425

RESUMO

BACKGROUND: Hexokinase I (HK1) is highly expressed in a variety of malignancies, regulates glycolytic pathway in cancer cells, and thus considered to be one of the promising molecular targets for cancer therapy. Nonetheless, the development of a specific inhibitor against HK1 remains elusive. PURPOSE: This study aims to elucidate the mechanism by which oridonin inhibits the proliferation and immune evasion of bladder cancer cells, specifically through the suppression of HK1. METHODS: To examine the mechanisms by which oridonin directly binds to cysteines of HK1 and inhibits bladder cancer growth, this study utilized a variety of methods. These included the Human Proteome Microarray, Streptavidin-agarose affinity assay, Biolayer Interferometry (BLI) ainding analysis, Mass Spectrometry, Cellular Thermal Shift Assay, Extracellular Acidification Rate measurement, and Xenotransplant mouse models. RESULTS: As indicated by our current findings, oridonin forms a covalent bond with Cys-813, located adjacently to glucose-binding domain of HK1. This suppresses the enzymatic activity of HK1, leading to an effective reduction of glycolysis, which triggers cell death via apoptosis in cells derived from human bladder cancer. Significantly, oridonin also inhibits lactate-induced PD-L1 expression in bladder cancer. Furthermore, pairing oridonin with a PD-L1 inhibitor amplifies the cytotoxicity of CD8+ T cells against bladder cancer. CONCLUSION: This research strongly suggests that oridonin serves as a covalent inhibitor of HK1. Moreover, it indicates that functional cysteine residue of HK1 could operate as viable targets for selective inhibition. Consequently, oridonin exhibits substantial potential for the evolution of anti-cancer agents targeting the potential therapeutic target HK1 via metabolism immunomodulation.


Assuntos
Antineoplásicos , Diterpenos do Tipo Caurano , Neoplasias da Bexiga Urinária , Animais , Camundongos , Humanos , Linhagem Celular Tumoral , Neoplasias da Bexiga Urinária/tratamento farmacológico , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/química , Antineoplásicos/farmacologia , Proliferação de Células , Apoptose
10.
Cell Oncol (Dordr) ; 47(3): 1043-1058, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38315285

RESUMO

PURPOSE: PIK3CA mutation or overexpression is associated with immunotherapy resistance in multiple cancer types, but is also paradoxically associated with benefit of COX-2 inhibition on patient survival of colorectal cancer (CRC) with mismatch repair deficiency (dMMR). This study examined whether and how PIK3CA status affected COX-2-mediated tumor inflammation and immunotherapy response of dMMR CRC. METHODS: Murine colon cancer cells MC38, CT26, and CT26-Mlh1-KO were used to construct PIK3CA knockdown and overexpression models to mimic dMMR CRC with PIK3CA dysregulation, and xenograft models were used to evaluate how PIK3CA regulate COX-2 expression, CD8+ T cells infiltration, tumor growth, and therapy response to anti-PD-L1 treatment using immunocompetent mice. Western blot was carried out to delineate the signaling pathways in human and mouse cancer cells, and immunohistochemical analysis together with bioinformatics analysis using human patient samples. RESULTS: PIK3CA upregulates COX-2 expression through MEK/ERK signaling pathway independent of AKT signaling to promote tumor inflammation and immunosuppression. PIK3CA knockdown profoundly reduced CT26 tumor growth in a CD8+ T cell-dependent manner, while PIK3CA overexpression significantly inhibited CD8+ T cells infiltration and promoted tumor growth. Furthermore, MEK or COX-2 inhibition augmented the anti-tumor activity of anti-PD-L1 immunotherapy on dMMR CRC mouse models, accompanied with increased CD8+ T cells infiltration and activated tumor microenvironment. CONCLUSION: Our results identified that the PIK3CA hyperactivation in dMMR CRC upregulated COX-2 through MEK signaling, which inhibited CD8+ T cells infiltration and promoted tumor growth, together led to immunotherapy resistance. COX-2 or MEK inhibition may relieve therapy resistance and promote therapy efficacy of anti-PD-1/PD-L1 immunotherapy for treating dMMR CRC with PIK3CA overexpression or activating mutation.


Assuntos
Linfócitos T CD8-Positivos , Classe I de Fosfatidilinositol 3-Quinases , Neoplasias Colorretais , Ciclo-Oxigenase 2 , Imunoterapia , Animais , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/terapia , Ciclo-Oxigenase 2/metabolismo , Humanos , Linhagem Celular Tumoral , Imunoterapia/métodos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Antígeno B7-H1/metabolismo , Reparo de Erro de Pareamento de DNA , Camundongos Endogâmicos BALB C , Feminino , Regulação Neoplásica da Expressão Gênica , Sistema de Sinalização das MAP Quinases , Transdução de Sinais , Neoplasias Encefálicas , Síndromes Neoplásicas Hereditárias
11.
Nat Commun ; 15(1): 1754, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409200

RESUMO

The response to programmed death-1 (PD-1) blockade varies in hepatocellular carcinoma (HCC). We utilize a panel of 16 serum factors to show that a circulating level of serum amyloid A (SAA) > 20.0 mg/L has the highest accuracy in predicting anti-PD-1 resistance in HCC. Further experiments show a correlation between peritumoral SAA expression and circulating SAA levels in patients with progressive disease after PD-1 inhibition. In vitro experiments demonstrate that SAA induces neutrophils to express PD-L1 through glycolytic activation via an LDHA/STAT3 pathway and to release oncostatin M, thereby attenuating cytotoxic T cell function. In vivo, genetic or pharmacological inhibition of STAT3 or SAA eliminates neutrophil-mediated immunosuppression and enhances antitumor efficacy of anti-PD-1 treatment. This study indicates that SAA may be a critical inflammatory cytokine implicated in anti-PD-1 resistance in HCC. Targeting SAA-induced PD-L1+ neutrophils through STAT3 or SAA inhibition may present a potential approach for overcoming anti-PD1 resistance.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Antígeno B7-H1/metabolismo , Neutrófilos/metabolismo , Proteína Amiloide A Sérica/metabolismo , Receptor de Morte Celular Programada 1 , Glicólise
12.
Cell Rep ; 43(4): 114094, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38613784

RESUMO

The importance of trained immunity in antitumor immunity has been increasingly recognized, but the underlying metabolic regulation mechanisms remain incompletely understood. In this study, we find that squalene epoxidase (SQLE), a key enzyme in cholesterol synthesis, is required for ß-glucan-induced trained immunity in macrophages and ensuing antitumor activity. Unexpectedly, the shunt pathway, but not the classical cholesterol synthesis pathway, catalyzed by SQLE, is required for trained immunity induction. Specifically, 24(S),25-epoxycholesterol (24(S),25-EC), the shunt pathway metabolite, activates liver X receptor and increases chromatin accessibility to evoke innate immune memory. Meanwhile, SQLE-induced reactive oxygen species accumulation stabilizes hypoxia-inducible factor 1α protein for metabolic switching into glycolysis. Hence, our findings identify 24(S),25-EC as a key metabolite for trained immunity and provide important insights into how SQLE regulates trained-immunity-mediated antitumor activity.


Assuntos
Camundongos Endogâmicos C57BL , Esqualeno Mono-Oxigenase , Animais , Esqualeno Mono-Oxigenase/metabolismo , Camundongos , Colesterol/metabolismo , Colesterol/biossíntese , Colesterol/análogos & derivados , Receptores X do Fígado/metabolismo , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Imunidade Inata/efeitos dos fármacos , Humanos , Linhagem Celular Tumoral
13.
J Robot Surg ; 18(1): 88, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386236

RESUMO

Transoral vestibular robotic thyroidectomy can really make the patient's body surface free of scar. This study aimed to compare the surgical and patient-related outcomes between the transoral vestibular robotic thyroidectomy and traditional low-collar incision thyroidectomy. The clinical data of 120 patients underwent transoral vestibular robotic thyroidectomy (TOVRT) or traditional low-collar incision thyroidectomy (TLCIT) were collected from May 2020 to October 2021. Propensity score matching analysis was used to minimize selection bias. All these patients were diagnosed with papillary thyroid carcinoma (PTC) through ultrasound-guided fine-needle aspiration prior to surgical intervention and surgical plan was tailored for each patient. An intraoperative recurrent laryngeal nerve (RLN) detection system was used in all patients, whose RLNs were identified and protected. We performed transoral vestibular robotic thyroidectomy with three intraoral incisions. Additional right axillary fold incisions were adopted occasionally to enhance fine reverse traction of tissue for radical tumor dissection. Clinical data including gender, age, tumor size, BMI, operation time, postoperative drainage volume and time, pain score, postoperative length of stay (LOS),number of lymph nodes removed, complications, and medical expense were observed and analyzed. Propensity score matching was used for 1:1 matching between the TOVRT group and the TLCIT group. All these patients accepted total thyroidectomy(or lobectomy) plus central lymph node dissection and all suffered from PTC confirmed by postoperative pathology. No conversion to open surgery happened in TOVRT group. The operative time of TOVRT group was longer than that of TLCIT group (P < 0.05). The postoperative drainage volume of TOVRT group was more than that of TLCIT group (P < 0.05). The drainage tube placement time of TOVRT group were longer than that of TLCIT group (P < 0.05). Significant differences were also found in intraoperative bleeding volume, pain score and medical expense between the two groups (P < 0.05). The incidence of perioperative common complications such as hypoparathyroidism and vocal cord paralysis in the two groups was almost identical (P > 0.05). However, there were some specific complications such as surgical area infection (one case), skin burn (one case), oral tear (two cases), and paresthesia of the lower lip and the chin (two cases) were found in TOVRT group. Obviously, the postoperative cosmetic effect of the TOVRT group was better than TLCIT group (P < 0.05). TOVRT is safe and feasible for low to moderate-risk PTC patients and is a potential alternative for patients who require no scar on their neck. Patients accepted TOVRT can get more satisfaction and have less psychologic injury caused by surgery.


Assuntos
Neoplasias , Procedimentos Cirúrgicos Robóticos , Humanos , Tireoidectomia/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Drenagem , Cicatriz , Dor
14.
Vet Res Forum ; 14(11): 583-588, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38169473

RESUMO

Feline calicivirus (FCV) is a highly contagious pathogen seriously affecting the upper respiratory tract and producing oral diseases in the feline. Despite widespread vaccination, the prevalence of FCV remains high. In this study, the FCV qingdao (qd)/2019/china was isolated from a domestic feline oropharyngeal swab collected from Qingdao, China. The virus was purified using the plaque assay and identified using the Polymerase chain reaction and indirect immunofluorescence assay methods, the capsid amino acid, VP1 of qd/2019/china, showed sequence identity with the other isolates ranging between 83.90% (ym3/2001/jp) and 91.10% (CH-JL4). The sequence of the capsid amino acid revealed qd/2019/china to be closely related to CH-JL4 and clustered with CH-JL4 in the phylogenetic tree. The phylo-genetic analysis indicated that the complete genomes (GenBank® accession No. MZ322896) of qd/2019/china and CH-JL4 were also classified into the same cluster. The recombination analysis with Simplot indicated that the qd/2019/china originated from the recombination of CH-JL4 and HRB-SS, and the region 3,821 - 5,301 nt originated from HRB-SS. Further, the region 3,821 - 5,301 nt were found to belong to the protease-polymerase (PP) of HRB-SS. Here, we isolated a new recombinant virus, FCV qd/2019/china. Therefore, these results would be beneficial for better understanding of the evolution and epidemiology of FCV.

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