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1.
Nat Prod Res ; : 1-5, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38087981

RESUMO

Three new cadinene sesquiterpenoids 1-3, were isolated from the aerial sections of Ageratina adenophora using various chromatographic techniques. Their structures were characterised by comprehensive spectroscopic investigations (including 1D, 2D-NMR and HRMS), and single crystal X-ray diffraction. The cytotoxic activity of new compounds 1-3 were evaluated by testing in vitro tumour growth inhibitory rate against five human tumour cell lines, HL-60, A-549, SMMC-7721, MDA-MB-231, and SW480.

2.
Fitoterapia ; 170: 105643, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37544332

RESUMO

The chemical analysis on the aerial sections of Eupatorium adenophorum Spreng. resulted in the identification of four unprecedented 5/5 fused bicyclosesquiterpenoids, eupatorid A (1), and its analogues named eupatorester A-C (2-4) using various chromatographic techniques. Their structures were unambiguously confirmed by detailed spectroscopic investigations (including 1D, 2D-NMR and HRMS), and single crystal X-ray diffraction. The anti-inflammatory activities, in vitro tumor growth inhibitory activities and antibacterial activities of these compounds were evaluated.


Assuntos
Ageratina , Ageratina/química , Estrutura Molecular , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química
3.
Oncoimmunology ; 12(1): 2217024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37261088

RESUMO

Colorectal cancer (CRC) is one of the top three malignant tumors in terms of morbidity, and the limited efficacy of existing therapies urges the discovery of potential treatment strategies. Immunotherapy gradually becomes a promising cancer treatment method in recent decades; however, less than 10% of CRC patients could really benefit from immunotherapy. It is pressing to explore the potential combination therapy to improve the immunotherapy efficacy in CRC patients. It is reported that Farnesoid X receptor (FXR) is deficiency in CRC and associated with immunity. Herein, we found that GW4064, a FXR agonist, could induce apoptosis, block cell cycle, and mediate immunogenic cell death (ICD) of CRC cells in vitro. Disappointingly, GW4064 could not suppress the growth of CRC tumors in vivo. Further studies revealed that GW4064 upregulated PD-L1 expression in CRC cells via activating FXR and MAPK signaling pathways. Gratifyingly, the combination of PD-L1 antibody with GW4064 exhibited excellent anti-tumor effects in CT26 xenograft models and increased CD8+ T cells infiltration, with 33% tumor bearing mice cured. This paper illustrates the potential mechanisms of GW4064 to upregulate PD-L1 expression in CRC cells and provides important data to support the combination therapy of PD-L1 immune checkpoint blockade with FXR agonist for CRC patients.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias Colorretais , Animais , Humanos , Camundongos , Neoplasias Colorretais/tratamento farmacológico , Imunoterapia , Receptores Citoplasmáticos e Nucleares
4.
Cancer Sci ; 114(5): 1958-1971, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36692137

RESUMO

As one of the common malignant cancer types, gastric cancer (GC) is known for late-stage diagnosis and poor prognosis. Overexpression of the receptor tyrosine kinase MET is associated with poor prognosis among patients with advanced stage GC. However, no MET inhibitor has been used for GC treatment. Like other tyrosine kinase inhibitors that fit the "occupancy-driven" model, current MET inhibitors are prone to acquired resistance. The emerging proteolysis targeting chimera (PROTAC) strategy could overcome such limitations through direct degradation of the target proteins. In this study, we successfully transformed the MET-targeted inhibitor crizotinib into a series of PROTACs, recruiting cereblon/cullin 4A E3 ubiquitin ligase to degrade the MET proteins. The optimized lead PROTAC (PRO-6 E) effectively eliminated MET proteins in vitro and in vivo, inhibiting proliferation and motility of MET-positive GC cells. In the MKN-45 xenograft model, PRO-6 E showed pronounced antitumor efficacy with a well-tolerated dosage regimen. These results validated PRO-6 E as the first oral PROTAC for MET-dependent GC.


Assuntos
Neoplasias Gástricas , Humanos , Crizotinibe/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteólise , Quimera de Direcionamento de Proteólise , Neoplasias Gástricas/tratamento farmacológico , Ubiquitina-Proteína Ligases/metabolismo
5.
MedComm (2020) ; 2(3): 297-314, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34766148

RESUMO

As key performers in intercellular communication, exosomes released by tumor cells play an important role in cancer development, including angiogenesis, cancer-associated fibroblasts activation, epithelial-mesenchymal transformation (EMT), immune escape, and pre-metastatic niche formation. Meanwhile, other cells in tumor microenvironment (TME) can secrete exosomes and facilitate tumor progression. Elucidating mechanisms regarding these processes may offer perspectives for exosome-based antitumor strategies. In this review, we mainly introduce the versatile roles of tumor or stromal cell derived exosomes in cancer development, with a particular focus on the biological capabilities and functionalities of their diverse contents, such as miRNAs, lncRNAs, and circRNAs. The potential clinical application of exosomes as biomarkers in cancer diagnosis and prognosis is also discussed. Finally, the current antitumor strategies based on exosomes in immunotherapy and targeted delivery for chemotherapeutic or biological agents are summarized.

6.
Front Oncol ; 11: 687120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34109132

RESUMO

Despite the dramatic advances in cancer research in the past few years, effective therapeutic strategies are urgently needed. Endothelial cell-specific molecule 1 (ESM-1), a soluble dermatan sulfate proteoglycan, also known as endocan, serves as a diagnostic and prognostic indicator due to its aberrant expression under pathological conditions, including cancer, sepsis, kidney diseases, and cardiovascular disease. Significantly, ESM-1 can promote cancer progression and metastasis through the regulation of tumor cell proliferation, migration, invasion, and drug resistant. In addition, ESM-1 is involved in the tumor microenvironment, containing inflammation, angiogenesis, and lymph angiogenesis. This article reviews the molecular and biological characteristics of ESM-1 in cancer, the underlying mechanisms, the currently clinical and pre-clinical applications, and potential therapeutic strategies. Herein, we propose that ESM-1 is a new therapeutic target for cancer therapy.

7.
Anesthesiology ; 124(5): 1041-52, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26872366

RESUMO

BACKGROUND: Patients undergoing major vascular surgery often develop postoperative pneumonia that impacts their outcomes. Conflicting data exist concerning the potential benefit of tapered-shaped cuffs on tracheal sealing. The primary objective of this study was to assess the efficiency of a polyvinyl chloride tapered-cuff endotracheal tube at reducing the postoperative pneumonia rate after major vascular surgery. Secondary objectives were to determine its impact on microaspiration, ventilator-associated pneumonia rate, and inner cuff pressure. METHODS: This prospective randomized controlled study included 109 patients who were randomly assigned to receive either spherical- (standard cuff) or taper-shaped (tapered cuff) endotracheal tubes inserted after anesthesia induction and then admitted to the intensive care unit after major vascular surgery. Cuff pressure was continuously recorded over 5 h. Pepsin and α-amylase concentrations in tracheal aspirates were quantified on postoperative days 1 and 2. The primary outcome was the early postoperative pneumonia frequency. RESULTS: Comparing the tapered-cuff with standard-cuff group, respectively, postoperative pneumonia rates were comparable (42 vs. 44%, P = 0.87) and the percentage (interquartile range) of cuff-pressure time with overinflation was significantly higher (16.1% [1.5 to 50] vs. 0.6% [0 to 8.3], P = 0.01), with a 2.5-fold higher coefficient of variation (20.2 [10.6 to 29.4] vs. 7.6 [6.2 to 10.2], P < 0.001). Although microaspiration frequencies were high, they did not differ between groups. CONCLUSION: For major vascular surgery patients, polyvinyl chloride tapered-cuff endotracheal tubes with intermittent cuff-pressure control did not lower the early postoperative pneumonia frequency and did not prevent microaspiration.


Assuntos
Intubação Intratraqueal/instrumentação , Pneumonia/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Procedimentos Cirúrgicos Vasculares/métodos , Idoso , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pepsina A/análise , Pneumonia/etiologia , Pneumonia/microbiologia , Pneumonia Aspirativa/prevenção & controle , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Complicações Pós-Operatórias/microbiologia , Pressão , Estudos Prospectivos , Método Simples-Cego , Resultado do Tratamento , alfa-Amilases/análise
8.
Anesthesiology ; 117(6): 1322-34, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23135260

RESUMO

BACKGROUND: In acute lung injury positive end-expiratory pressure (PEEP) and recruitment maneuver are proposed to optimize arterial oxygenation. The aim of the study was to evaluate the impact of such a strategy on lung histological inflammation and hyperinflation in pigs with acid aspiration-induced lung injury. METHODS: Forty-seven pigs were randomly allocated in seven groups: (1) controls spontaneously breathing; (2) without lung injury, PEEP 5 cm H2O; (3) without lung injury, PEEP titration; (4) without lung injury, PEEP titration + recruitment maneuver; (5) with lung injury, PEEP 5 cm H2O; (6) with lung injury, PEEP titration; and (7) with lung injury, PEEP titration + recruitment maneuver. Acute lung injury was induced by intratracheal instillation of hydrochloric acid. PEEP titration was performed by incremental and decremental PEEP from 5 to 20 cm H2O for optimizing arterial oxygenation. Three recruitment maneuvers (pressure of 40 cm H2O maintained for 20 s) were applied to the assigned groups at each PEEP level. Proportion of lung inflammation, hemorrhage, edema, and alveolar wall disruption were recorded on each histological field. Mean alveolar area was measured in the aerated lung regions. RESULTS: Acid aspiration increased mean alveolar area and produced alveolar wall disruption, lung edema, alveolar hemorrhage, and lung inflammation. PEEP titration significantly improved arterial oxygenation but simultaneously increased lung inflammation in juxta-diaphragmatic lung regions. Recruitment maneuver during PEEP titration did not induce additional increase in lung inflammation and alveolar hyperinflation. CONCLUSION: In a porcine model of acid aspiration-induced lung injury, PEEP titration aimed at optimizing arterial oxygenation, substantially increased lung inflammation. Recruitment maneuvers further improved arterial oxygenation without additional effects on inflammation and hyperinflation.


Assuntos
Lesão Pulmonar/patologia , Lesão Pulmonar/terapia , Pneumonia/patologia , Pneumonia/terapia , Respiração com Pressão Positiva/métodos , Recrutamento Neurofisiológico/fisiologia , Animais , Feminino , Ácido Clorídrico/administração & dosagem , Ácido Clorídrico/efeitos adversos , Lesão Pulmonar/induzido quimicamente , Pneumonia/induzido quimicamente , Distribuição Aleatória , Mecânica Respiratória/fisiologia , Suínos
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(8): 841-4, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20193211

RESUMO

OBJECTIVE: To study the analytical sensitivity on 31 HBsAg enzyme immunoassy (EIA) test kits. METHODS: Thirty one HBsAg EIA kits produced by domestic or overseas manufactories and applied for approval during May 2007 to May 2008, were evaluated using the national reference panels. The hyperbolic curve of the log A value and log concentration for the national sensitivity standards was established. The cut-off value of each kit was substituted into the curvilinear equation to determine the analytical sensitivity which was compared between different HBsAg EIA kits. RESULTS: Twenty seven (351 lots) domestic and 4 (27 lots) overseas kits were compared. Among 378 lots of the 31 HBsAg EIA kits, only 2 lots of the domestic kits had a lower sensitivity when tested with the national HBsAg reference panels, with an average approvalr ate of 99.43% (349/351). The mean analytical sensitivity of the domestic kits for adr, adw, ay serotypes were 0.307, 0.419, 0.513 ng/ml, respectively. There was a significant difference between serotypes (F = 97.30, P < 0.01). The mean analytical sensitivity of the overseas kits for adr, adw, ay serotypes were 0.054, 0.066, 0.050 ng/ml respectively, with no significant difference between serotypes (F = 0.65, P > 0.05). The analytical sensitivity of the overseas kits for all the three serotypes was higher than that of the domestic kits (P < 0.01). There was no significant difference found between the analytical sensitivities of the kits produced by the same manufactory using 30- or 60-minute incubation of detection (P > 0.05). In contrast, there was significant difference noticed between the analytical sensitivities of the kits produced by the same manufactory when tested for 10 or 15-minute coloration of the results (P < 0.01). CONCLUSION: Analytical sensitivity of the HBsAg EIA domestic kits should be further improved, especially for detecting adw and ay serotypes.


Assuntos
Antígenos de Superfície da Hepatite B/isolamento & purificação , Técnicas Imunoenzimáticas/métodos , Kit de Reagentes para Diagnóstico/normas , Antígenos de Superfície da Hepatite B/classificação , Humanos , Valores de Referência , Sensibilidade e Especificidade , Sorotipagem
10.
Artigo em Chinês | MEDLINE | ID: mdl-19105354

RESUMO

OBJECTIVE: To establish the national quantity standard of hepatitis B surface antigen according to the world health organization' s standard material and prepare the national liner reference panel for hepatitis B surface antigen. METHODS: Sera from hepatitis B patients and health blood donors in different areas were collected and detected by domastic HBsAg kits, anti-HBs kits, HBeAg kits, anti-HBe kits, anti-HBc kits and anti-HCV, and then confirmed by the kits produced by Abbott, which was approved by WHO. One serum with high concentration of HBsAg was calibrated with the standard sample of WHO. And then it was diluted by 1.5 fold as the liner HBsAg reference panel. RESULTS: The HBsAg concentration of one serum was 1226 IU/ml calibrated by 21 independent standardization measurements with 7 kinds of kits. The coefficient of variation of each calibration were less then 15%. A panel contained 8 serial dilutions was established as the national liner HBsAg reference panel. The permitted range of every dilution was stipulated and the stability of the panel was detected by accelerated test. CONCLUSIONS: The national quantity standard of hepatitis B surface antigen was established and the national quantitative reference panel for HBsAg which contains eight liner serum was developed.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B/virologia , Técnicas Imunoenzimáticas/métodos , Técnicas Imunoenzimáticas/normas , Kit de Reagentes para Diagnóstico/normas , China , Humanos , Padrões de Referência
11.
Neurobiol Dis ; 14(3): 357-64, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14678753

RESUMO

Mutations in the parkin gene are responsible for autosomal recessive parkinsonism. The disease-linked missense mutations are highly concentrated in the RING-IBR-RING domains of Parkin. In this study, we investigated the consequences of several missense parkin gene mutations in cell culture. We have demonstrated that two of these mutations (C289G and C418R), which replace consensus cysteine residues in the RING domains, significantly decrease the solubility of Parkin in cells. Upon overexpression, the presumably misfolded proteins formed cytoplasmic aggregates that concentrated into large perinuclear inclusion bodies when proteasome activity was inhibited. This process required active microtubule-dependent retrograde transport, as previously reported for aggresome formation. These results provide information on the molecular basis of the loss of function caused by mutations of critical residues in Parkin. They also contribute to our understanding of the cellular mechanism underlying the aggregation of mutant Parkin.


Assuntos
Corpos de Inclusão/genética , Mutação de Sentido Incorreto/genética , Neurônios/metabolismo , Doença de Parkinson/genética , Ubiquitina-Proteína Ligases/metabolismo , Animais , Células COS , Cisteína Endopeptidases/metabolismo , Humanos , Corpos de Inclusão/metabolismo , Substâncias Macromoleculares , Microtúbulos/metabolismo , Complexos Multienzimáticos/metabolismo , Neurônios/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Complexo de Endopeptidases do Proteassoma , Dobramento de Proteína , Estrutura Terciária de Proteína/genética , Transporte Proteico/fisiologia , Solubilidade , Ubiquitina-Proteína Ligases/genética , Ubiquitinas/metabolismo
12.
J Med Virol ; 67(4): 516-21, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12115997

RESUMO

Evidence that hepatitis E is zoonotic is accumulating. Serum samples were collected from pigs, cattle, and goats from various regions of China to determine whether they had been infected with hepatitis E virus (HEV). An in-house enzyme immunoassay (EIA) and reverse transcriptase-polymerase chain reaction (RT-PCR) with primers from open reading frame (ORF) 2 were used to detect anti-HEV antibodies and HEV RNA. The mean positivity rates of anti-HEV antibody for pigs and cattle were 78.8% and 6.3% but none of the goat sera were positive. Pigs may be more susceptible to infection with HEV than cattle or goats. Five of 263 pig sera were positive for HEV RNA and four of these five were also positive for anti-HEV. The PCR products (nt 6007-6354) were cloned and sequenced and compared to other HEV sequences in the nucleotide databases. The five sequences shared 83-93% identity to each other at the nucleotide level and 74-79%, 73-74%, 73-78%, and 83-99% identity to HEV genotypes 1, 2, 3, and 4, respectively. They were closely related to human isolates of HEV genotype 4. Phylogenetic analyses also place these swine sequences in HEV genotype 4, resembling most closely viruses isolated from Chinese patients with acute hepatitis. These data support the hypothesis that sporadic hepatitis E in China is zoonotic.


Assuntos
Animais Domésticos/virologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/isolamento & purificação , Hepatite E/veterinária , Hepatite E/virologia , Zoonoses/virologia , Animais , Animais Domésticos/imunologia , Bovinos , China/epidemiologia , Cabras/imunologia , Cabras/virologia , Anticorpos Anti-Hepatite/sangue , Anticorpos Anti-Hepatite/imunologia , Hepatite E/imunologia , Hepatite E/transmissão , Vírus da Hepatite E/classificação , Vírus da Hepatite E/imunologia , Humanos , Técnicas Imunoenzimáticas , Macaca mulatta/virologia , Filogenia , RNA Viral/análise , RNA Viral/sangue , RNA Viral/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estudos Soroepidemiológicos , Suínos/imunologia , Suínos/virologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/virologia , Zoonoses/transmissão
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