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1.
Org Lett ; 26(24): 5074-5081, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38857312

RESUMO

The nickel/photoredox dual catalysis system is an efficient conversion platform for the difunctionalization of unsaturated hydrocarbons. Herein, we disclose the first dual nickel/photoredox-catalyzed intramolecular 1,2-arylsulfonylation of allenes, which can accurately construct a C(sp2)-C(sp2) bond and a C(sp3)-S bond. The reaction exhibits excellent chemoselectivity and regioselectivity, allowing modular conformations of a diverse series of 3-sulfonylmethylbenzofuran derivatives. Control experiments showed that the bipyridine ligand is crucial for the formation of a stable σ-alkyl nickel intermediate, providing the possibility for sulfonyl radical insertion. Meanwhile, the electrophilic sulfonyl radical facilitates further oxidative addition of the σ-alkyl nickel intermediate and inhibits addition with allenes. In addition, control experiments, cyclic voltammetry tests, Stern-Volmer experiments, and density functional theory calculations afford evidence for the Ni(0)/Ni(I)/Ni(II)/Ni(III) pathway in this 1,2-arylsulfonylation.

2.
World J Clin Oncol ; 15(3): 456-463, 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38576599

RESUMO

BACKGROUND: SMARCA4 is a component of chromatin remodeling of SWItch/sucrose-nonfermenting (SWI/SNF) complexes and plays an essential role in oncogenesis. SMARCA4-deficient malignancies arising from the gastrointestinal tract are rare and have a poor prognosis. There is no standard treatment for advanced and undifferentiated SMARCA4-deficient duodenal malignancies. Programmed death 1 (PD-1) antibodies, known as immune checkpoint inhibitor antibodies, potentially play a role in treating gastrointestinal tract malignancies. CASE SUMMARY: We present two patients with SMARCA4 deficiency and TP53 gene mutation in advanced undifferentiated carcinomas of the duodenum. For both patients, SMARCA4 deficiency was confirmed by immunohistochemical staining for the BRG1 protein, while TP53 gene mutations were observed via next-generation sequencing. Both patients were administered chemotherapy in combination with an anti-PD-1 antibody. The two patients exhibited completely different responses to treatment and had different prognoses. Case 1 experienced rapid progression after PD-1 infusion and chemotherapy, case 2 experienced a remarkable response after treatment, and the progression-free survival was more than 6 months. CONCLUSION: This study described our clinical and pathological observations of SMARCA4-deficient advanced undifferentiated carcinoma of the duodenum. PD-1 combined with chemotherapy showed a certain efficacy in select patients, providing options for treating these highly malignant tumors. Patients with liver metastases had a worse prognosis than did those with only lymph node metastasis.

3.
Signal Transduct Target Ther ; 9(1): 69, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38531869

RESUMO

The Orthopoxvirus genus, especially variola virus (VARV), monkeypox virus (MPXV), remains a significant public health threat worldwide. The development of therapeutic antibodies against orthopoxviruses is largely hampered by the high cost of antibody engineering and manufacturing processes. mRNA-encoded antibodies have emerged as a powerful and universal platform for rapid antibody production. Herein, by using the established lipid nanoparticle (LNP)-encapsulated mRNA platform, we constructed four mRNA combinations that encode monoclonal antibodies with broad neutralization activities against orthopoxviruses. In vivo characterization demonstrated that a single intravenous injection of each LNP-encapsulated mRNA antibody in mice resulted in the rapid production of neutralizing antibodies. More importantly, mRNA antibody treatments showed significant protection from weight loss and mortality in the vaccinia virus (VACV) lethal challenge mouse model, and a unique mRNA antibody cocktail, Mix2a, exhibited superior in vivo protection by targeting both intracellular mature virus (IMV)-form and extracellular enveloped virus (EEV)-form viruses. In summary, our results demonstrate the proof-of-concept production of orthopoxvirus antibodies via the LNP-mRNA platform, highlighting the great potential of tailored mRNA antibody combinations as a universal strategy to combat orthopoxvirus as well as other emerging viruses.


Assuntos
Orthopoxvirus , Vacínia , Animais , Camundongos , Terapia Combinada de Anticorpos , Vacínia/prevenção & controle , Anticorpos Antivirais , Vaccinia virus/genética
4.
Chem Asian J ; 18(18): e202300606, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37500593

RESUMO

The synergistic systems of photoredox and copper catalyst have already appeared as a novel formation of green synthetic chemistry, which open new avenues for chemical synthesis applications. We describe a novel strategy for the cyclization of alkyne-tethered α-bromocarbonyls initiated by the cleavage of C(sp3 )-Br bond via the collaboration of photoredox and copper catalyst. The present protocol exhibits mildness using economical copper catalyst and visible-light at room temperature. The gram-scale and sunlight irradiation experiments proceeded smoothly to show the practicality of the methodology. It is notable that the newly generated oxygen in the product originates from H2 O.

5.
Front Oncol ; 13: 1165040, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324019

RESUMO

Targeted therapy has been standardized in front-line therapies for metastatic colorectal cancer (mCRC), while explicit recommendations for third- or later-line are still lacking. This study evaluated the efficacy and safety of combining targeted therapy with chemotherapy in the third- or later-line treatment for mCRC via meta-analysis, providing evidence-based guidance for clinical or research practice. Comprehensive retrieval of related studies was conducted according to the PRISMA guideline. Studies were stratified with patient characteristics and pharmacological classification of the drugs. For the data available for quantitative analysis, pooled overall response rate, disease control rate, hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS), and adverse events rate with respective 95% confidence intervals (CIs) were calculated. A total of 22 studies (1,866 patients) were included in this meta-analysis. Data from 17 studies (1,769 patients) involving targets of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) were extracted for meta-analyses. The overall response rates for monotherapy and combined therapy were 4% (95% CI: 3%, 5%) and 20% (95% CI: 11%, 29%). The pooled HRs (combined therapy vs. mono) for OS and PFS were 0.72 (95% CI: 0.53, 0.99) and 0.34 (95% CI: 0.26, 0.45). Another five studies were included in narrative depiction, involving targets of BRAF, HER-2, ROS1, and NTRK. The findings of this meta-analysis indicate that VEGF and EGFR inhibitors manifest promising clinical response rates and prolonged survival in the treatment of mCRC with acceptable adverse events.

6.
Chemistry ; 29(46): e202301390, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37280159

RESUMO

Chemodivergent tandem radical cyclization offers exciting possibilities for the synthesis of structurally diverse cyclic compounds. Herein, we revealed a chemodivergent tandem cyclization of alkene-substituted quinazolinones under metal- and base-free conditions, this transformation is initiated by alkyl radicals produced from oxidant-induced α-C(sp3 )-H functionalization of alkyl nitriles or esters. The reaction resulted in the selective synthesis of a series of mono- and di-alkylated ring-fused quinazolinones by modulating the loading of oxidant, reaction temperature, and reaction time. Mechanistic investigations show that the mono-alkylated ring-fused quinazolinones is constructed by the key process of 1,2-hydrogen shift, whereas the di-alkylated ring-fused quinazolinones is mainly achieved through crucial steps of resonance and proton transfer. This protocol is the first example of remote second alkylation on the aromatic ring via α-C(sp3 )-H functionalization and difunctionalization achieved by association of two unsaturated bonds in radical cyclization.

7.
Emerg Microbes Infect ; 12(1): 2191741, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36920800

RESUMO

Pulmonary anthrax is the most fatal clinical form of anthrax and currently available injectable vaccines do not provide adequate protection against it. Hence, next-generation vaccines that effectively induce immunity against pulmonary anthrax are urgently needed. In the present study, we prepared an attenuated and low protease activity Bacillus anthracis strain A16R-5.1 by deleting five of its extracellular protease activity-associated genes and its lef gene through the CRISPR-Cas9 genome editing system. This mutant strain was then used to formulate a lethal toxin (LeTx)-free culture supernatant extract (CSE) anthrax vaccine, of which half was protective antigen (PA). We generated liquid, powder, and powder reconstituted formulations that could be delivered by aerosolized intratracheal inoculation. All of them induced strong humoral, cellular, and mucosal immune responses. The vaccines also produced LeTx neutralizing antibodies and conferred full protection against the lethal aerosol challenges of B. anthracis Pasteur II spores in mice. Compared to the recombinant PA vaccine, the CSE anthrax vaccine with equal PA content provided superior immunoprotection against pulmonary anthrax. The preceding results suggest that the CSE anthrax vaccine developed herein is suitable and scalable for use in inhalational immunization against pulmonary anthrax.


Assuntos
Vacinas contra Antraz , Antraz , Bacillus anthracis , Camundongos , Animais , Antraz/prevenção & controle , Vacinas contra Antraz/genética , Antígenos de Bactérias/genética , Pós , Bacillus anthracis/genética , Vacinas Sintéticas , Peptídeo Hidrolases , Anticorpos Antibacterianos
8.
Biomed Environ Sci ; 35(9): 821-829, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36189997

RESUMO

Objective: This study aimed to investigate the regulation of histone-like nucleoid structuring protein (H-NS) on biofilm formation and cyclic diguanylate (c-di-GMP) synthesis in Vibrio parahaemolyticus RIMD2210633. Methods: Regulatory mechanisms were analyzed by the combined utilization of crystal violet staining, quantification of c-di-GMP, quantitative real-time polymerase chain reaction, LacZ fusion, and electrophoretic-mobility shift assay. Results: The deletion of hns enhanced the biofilm formation and intracellular c-di-GMP levels in V. parahaemolyticus RIMD2210633. H-NS can bind the upstream promoter-proximal DNA regions of scrA, scrG, VP0117, VPA0198, VPA1176, VP0699, and VP2979 to repress their transcription. These genes encode a group of proteins with GGDEF and/or EAL domains associated with c-di-GMP metabolism. Conclusion: One of the mechanisms by which H-NS represses the biofilm formation by V. parahaemolyticus RIMD2210633 may be via repression of the production of intracellular c-di-GMP.


Assuntos
Vibrio parahaemolyticus , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , GMP Cíclico/análogos & derivados , Regulação Bacteriana da Expressão Gênica , Violeta Genciana , Histonas/genética , Histonas/metabolismo , Vibrio parahaemolyticus/genética
9.
Emerg Microbes Infect ; 11(1): 2350-2358, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36069671

RESUMO

Zika virus (ZIKV) is primarily transmitted through mosquito bites and sexual contact, and vertical transmission of ZIKV has also been observed in humans. In addition, ZIKV infection via unknown transmission routes has been frequently reported in clinical settings. However, whether ZIKV can be transmitted via aerosol routes remains unknown. In this study, we demonstrated that aerosolized ZIKV is fully infectious in vitro and in vivo. Remarkably, intratracheal (i.t.) inoculation with aerosolized ZIKV led to rapid viremia and viral secretion in saliva, as well as robust humoral and innate immune responses in guinea pigs. Transcriptome analysis further revealed that the expression of genes related to viral processes, biological regulation and the immune response was significantly changed. Together, our results confirm that aerosolized ZIKV can result in systemic infection and induce both innate and adaptive immune responses in guinea pigs, highlighting the possibility of ZIKV transmission via aerosols.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Cobaias , Humanos , Imunidade Humoral , Transmissão Vertical de Doenças Infecciosas , Viremia , Zika virus/fisiologia
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-976139

RESUMO

@#Objective To analyze the occupational burnout status and its influencing factors of border guards in the prevention ( - )Methods and control of coronavirus disease COVID 19 . A total of 1 313 border guards who participate in the prevention and control of epidemic diseases were selected as research subjects using the random cluster sampling method. Military Occupational Burnout Scale and Military Occupational Stress Scale were used to investigate the occupational burnout status and Results occupational stress in the research subjects. The median and 25th and 75th percentiles of military occupational ( , ) ( , ), burnout and occupational stress total scores were 9.0 3.0 15.0 and 76.0 70.0 86.0 respectively. About 73.1% of the subjects were suffered from high occupational stress. The results of multiple linear regression analysis indicated that the higher the scores of interpersonal relationship, military special life, work pressure, unclear role and leadership ability factor in P occupational stress, and the lower the score of personal development, the more serious the occupational burnout (all <0.05 ) , after excluding the influence of confounding factors; subjects with panic psychology inconvenience caused by closed , management fear on accountability for poor prevention and no personal hobbies had more serious occupational burnout than ( P ) Conclusion - , subjects without those factors all <0.05 . In the period of COVID 19 prevention the level of occupational burnout and occupational stress of border guards were generally low. The occupational burnout was mainly affected by occupational stress and fear of the epidemic.

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