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1.
Food Chem ; 439: 138168, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103491

RESUMO

Papaya is a climacteric fruit that undergoes rapid ripening and quality deterioration during postharvest storage, resulting in significant economic losses. This study employed biochemical techniques and targeted metabolomics to investigate the impact of exogenous AsA + CTS application on the energy metabolism regulation of papaya fruit during postharvest storage. We found that AsA + CTS treatment significantly increased the levels of key metabolic compounds and enzymes, such as adenosine triphosphate (ATP), adenosine diphosphate (ADP), and the energy charge, as well as the succinic acid content and the activities of succinic dehydrogenase (SDH), cytochrome c oxidase (CCO), H+-ATPase, and Ca2+-ATPase. Moreover, AsA + CTS coating augmented the nicotinamide adenine dinucleotide kinase (NADK) activity and increased the NADH and NADPH concentrations. Regarding sugar metabolism, it increased the activities of 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase and raised d-glucose-6-phosphate levels. These findings suggest that AsA + CTS coating application can mitigate the metabolic deterioration and sustain a primary metabolism homeostasis in papaya fruit by enhancing the tricarboxylic acid (TCA) cycle and pentose phosphate pathway (PPP), thereby preserving their quality attributes during postharvest storage.


Assuntos
Carica , Quitosana , Frutas/química , Ácido Ascórbico/análise , Quitosana/análise , Homeostase
2.
Plants (Basel) ; 12(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687296

RESUMO

Tropane alkaloids (TAs) are large secondary metabolite alkaloids that find extensive applications in the synthesis of antidotes, anesthetics, antiemetics, motion sickness drugs, and antispasmodics. The current production method primarily depends on extraction from medicinal plants of the Solanaceae family. Elicitation, as a highly effective biotechnological approach, offers significant advantages in augmenting the synthesis of secondary metabolites. The advantages include its simplicity of operation, low cost, and reduced risk of contamination. This review focuses on the impact of elicitation on the biosynthesis of TAs from three aspects: single-elicitor treatment, multiple-elicitor treatment, and the combination of elicitation strategy with other strategies. Some potential reasons are also proposed. Plant hormones and growth regulators, such as jasmonic acid (JA), salicylic acid (SA), and their derivatives, have been extensively employed in the separate elicitation processes. In recent years, novel elicitors represented by magnetic nanoparticles have emerged as significant factors in the investigation of yield enhancement in TAs. This approach shows promising potential for further development. The current utilization of multi-elicitor treatment is constrained, primarily relying on the combination of only two elicitors for induction. Some of these combinations have been found to exhibit synergistic amplification effects. However, the underlying molecular mechanism responsible for this phenomenon remains largely unknown. The literature concerning the integration of elicitation strategy with other strategies is limited, and several research gaps require further investigation. In conclusion, the impact of various elicitors on the accumulation of TAs is well-documented. However, further research is necessary to effectively implement elicitation strategies in commercial production. This includes the development of stable bioreactors, the elucidation of regulatory mechanisms, and the identification of more potent elicitors.

3.
Transl Cancer Res ; 8(4): 1381-1394, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35116881

RESUMO

BACKGROUND: Stereotactic body radiotherapy (SBRT) has been increasingly recognized as a favourable alternative to surgical resection for early-stage non-small cell lung cancer (NSCLC). Many retrospective analyses compared the efficacy of SBRT with that of surgery for NSCLC. However, the difference in efficacy between SBRT and surgery in patients with early-stage NSCLC remains unclear. METHODS: We searched PubMed, the Cochrane Library, EMBASE and the Chinese Biomedical Literature Database from inception to March 14, 2018, to identify studies comparing SBRT with surgery in the treatment of stage I/II NSCLC. STATA 12.0 software was used to perform the meta-analysis. RESULTS: A total of 15 studies that carried out propensity score matching (PSM) were included. In this meta-analysis, patients with SBRT had worse overall survival (OS) than those with surgery, but the analysis restricting studies to the same adjustment factors showed that the difference in OS gradually decreased with the increase in comparable matching characteristics between the two groups and that there was eventually no significant difference. Patients treated with SBRT achieved similar cause-specific survival (CSS), local control, regional control, loco-regional control, and distant control compared with surgery. In addition, a separate analysis of 6 studies that compared SBRT with lobectomy also showed that with the increase in comparable matching characteristics between surgery and SBRT, the OS differences gradually decreased, and there was eventually no significant difference. CONCLUSIONS: In this study, we found more favourable OS for stage I/II NSCLC treated with surgery, but when there were increasing numbers of comparable matching characteristics between surgery and SBRT, the differences in the survival rate were reduced to the point that they were not significant. The CSS and recurrence (local, regional, or disseminated) differences between surgery and SBRT were also not significant. Therefore, SBRT has the potential to be an alternative to surgical treatment in patients with stage I/II NSCLC, but these findings need to be confirmed by large-sample, long-term follow-up randomized clinical studies.

4.
Ultrasound Med Biol ; 42(2): 549-60, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26651601

RESUMO

A novel lipid micro-bubble (MB) loaded with docetaxel (DOC-MB) was investigated in a previous study. However, its anti-tumor effects and mechanism of action in combination with low-frequency ultrasound (LFUS) in vivo are still unclear. DOC-MBs containing 5.0 mg of DOC were prepared by lyophilization with modification via ultrasonic emulsification. Then, the effects of DOC-MBs combined with LFUS on tumor growth, proliferating cell nuclear antigen (PCNA) expression and cell apoptosis, as well as local DOC delivery, were investigated in H22 hepatocellular carcinoma (HCC)-bearing mice. Compared with the previously prepared DOC-MBs (1.6 mg of DOC loaded), the encapsulation efficiency (81.2% ± 3.89%) and concentration ([7.94 ± 0.04] × 10(9) bubbles/mL) of the DOC-MBs containing 5.0 mg of DOC were higher, but the bubble size (1.368 ± 0.004 µm) was smaller. After treatment with the DOC-MBs and LFUS, the H22 HCC growth inhibition rate was significantly increased, PCNA expression in tumor tissue was significantly inhibited and local release of DOC was induced. In conclusion, new DOC-MBs containing 5.0 mg of DOC were successfully prepared with a high encapsulation efficiency and superior bubble size and concentration, and their combination with LFUS significantly enhanced the anti-tumor effect of DOC in H22 HCC-bearing mice by inhibiting tumor cell proliferation and increasing local drug delivery.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Preparações de Ação Retardada/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Microbolhas/uso terapêutico , Sonicação/métodos , Taxoides/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/síntese química , Docetaxel , Feminino , Neoplasias Hepáticas/patologia , Camundongos , Resultado do Tratamento
5.
J Thromb Thrombolysis ; 37(3): 303-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23943336

RESUMO

A new microbubble loaded with urokinase (uPA-MB) was explored in a previous study. However, its zeta potential and ultrasound contrast imaging properties and its thrombolytic effects when combined with low-frequency ultrasound (LFUS) were unclear. The zeta potential and ultrasound contrast imaging property of 5 uPA-MBs loading with 50,000 IU uPA was respectively detected using a Malvern laser particle analyzer and a Logiq 9 digital premium ultrasound system. Its ultrasound contrast imaging property was performed on the livers of two healthy dogs to compare with SonoVue. And the clot mass loss rate, D-dimer concentration and surface morphology of the clot residues were measured to evaluate the thrombolytic effect after treatment with three doses of 5 uPA-MBs combined with LFUS in vitro. The zeta potential of 5 uPA-MBs (-27.0 ± 2.40 mV) was higher than that of normal microbubbles (-36.95 ± 1.77 mV). Contrast-enhanced imaging of the hepatic vessels using 5 uPA-MBs was similar to SonoVue, while the imaging duration of 5 uPA-MBs (10 min) was longer than SonoVue (6 min). The thrombolytic effect of three doses of uPA-MBs combined with LFUS was significantly better than that of the control group and showed dose dependence. The 5 uPA-MBs have a negative charge on their surface and good echogenicity as ultrasound contrast agents. The 5 uPA-MBs combined with LFUS can promote thrombolysis in a dose-dependent manner.


Assuntos
Meios de Contraste/farmacologia , Fibrinolíticos/uso terapêutico , Microbolhas , Terapia Trombolítica , Trombose , Ultrassonografia , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Animais , Cães , Fígado/irrigação sanguínea , Fígado/ultraestrutura , Terapia Trombolítica/instrumentação , Terapia Trombolítica/métodos , Trombose/diagnóstico por imagem , Trombose/terapia , Ultrassonografia/instrumentação , Ultrassonografia/métodos
6.
Pharm Res ; 30(6): 1574-85, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23417512

RESUMO

PURPOSE: To develop a novel docetaxel (DOC)-loaded lipid microbubbles (MBs) for achieving target therapy and overcoming the poor water-solubility drawback of DOC. METHODS: A novel DOC-loaded microbubble (DOC + MB) was prepared by lyophilization and the physicochemical properties including ultrasound contrast imaging of the liver were measured. The anti-tumor effect of the DOC + MBs combined with low-frequency ultrasound (LFUS; 0.8 Hz, 2.56 W/cm², 50% cycle duty) on the DLD-1 cancer cell line was examined using an MTT assay. RESULTS: The physicochemical properties of the two tested formats of DOC + MBs (1.0 mg and 1.6 mg) was shown: concentration, (6.74 ± 0.02) × 108 bubbles/mL and (8.27 ± 0.15) × 108 bubbles/mL; mean size, 3.296 ± 0.004 µm and 3.387 ± 0.005 µm; pH value, 6.67 ± 0.11 and 6.56 ± 0.05; release rate, 3.41% and 12.50%; Zeta potential, -37.95 ± 7.84 mV and -44.35 ± 8.70 mV; and encapsulation efficiency, 54.9 ± 6.21% and 46.3 ± 5.69%, respectively. Compared with SonoVue, the DOC + MBs similarly enhanced the echo signal of the liver imaging. The anti-tumor effect of the DOC + MBs/LFUS group was significantly better than that of DOC alone and that of the normal MBs/LFUS groups. CONCLUSIONS: The self-made DOC + MBs have potential as a new ultrasound contrast agent and drug-loaded microbubble, and can obviously enhance the antitumor effect of DOC under LFUS exposure.


Assuntos
Antineoplásicos/química , Sistemas de Liberação de Medicamentos/métodos , Microbolhas/uso terapêutico , Taxoides/química , Taxoides/uso terapêutico , Ultrassom/métodos , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Docetaxel , Cães , Estabilidade de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Lipídeos/administração & dosagem , Lipídeos/química , Fígado/diagnóstico por imagem , Fígado/efeitos dos fármacos , Solubilidade , Ultrassonografia , Água/química
7.
Thromb Res ; 129(5): e217-22, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22445430

RESUMO

INTRODUCTION: Z4A5 is a novel peptide that inhibits platelet aggregation and formation of platelet thrombi, but the mechanism of its anti-platelet effects remains unknown. This study explores the anti-platelet effect and mechanism of Z4A5. METHODS: We investigated the anti-platelet activity of Z4A5 on platelet aggregation induced by adenosine diphosphate (ADP), arachidonic acid (AA) and thrombin (TH) in human platelet-rich plasma (PRP). Fibrinogen and PAC-1 binding to glycoproteinIIb/IIIa (GPIIb/IIIa) were measured by flow cytometry. In addition, we investigated the integrin specificity of Z4A5 in attachment and detachment assays using human umbilical vein endothelial cells (HUVEC) and assessed the relative cell number using the MTT assay. RESULTS: In vitro, Z4A5 inhibited ADP-, AA- and TH-induced human platelet aggregation with IC(50) values of 0.46 ± 0.05 µM (n = 10), 0.23 ± 0.0 5 µM (n = 10) and 0.21 ± 0.02 µM (n = 10), respectively. Z4A5 inhibited fibrinogen, and PAC-1 bound to platelet GPIIb/IIIa with IC(50) values of 0.48 ± 0.07 µM (n = 8) and 0.63 ± 0.12 µM (n = 6), respectively. Z4A5 failed to inhibit α(V)ß(3) integrin-mediated HUVEC attachment to vitronectin and did not cause any significant detachment of HUVEC monolayer when compared with the controls. CONCLUSIONS: Z4A5 is a potential anti-platelet drug that inhibits fibrinogen binding to GPIIb/IIIa, but does not affect the structurally similar integrin α(V)ß(3).


Assuntos
Plaquetas/efeitos dos fármacos , Fibrinolíticos/farmacologia , Oligopeptídeos/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Linhagem Celular , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/farmacologia
8.
Ultrasound Med Biol ; 37(11): 1828-37, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21925787

RESUMO

Urokinase (uPA) is used widely for thrombosis therapy in the clinic. However, ways to minimize its adverse effect of hemorrhage are still being studied. As a new technique for the local delivery of genes and drugs, ultrasound (US) contrast agents, microbubbles (MBs), have been mentioned. The purpose of this study is to explore a more efficacious and safer thrombolytic method by preparing three groups of self-made microbubble-loading uPA (uPA-MBs) (1 uPA-MBs, 5 uPA-MBs and 10 uPA-MBs) using freeze-drying methods and measuring their thrombolysis when combined in vitro with low-frequency US. The results showed the mean concentration, mean diameter, pH value and encapsulation efficiency of uPA of the three groups of uPA-MBs were approximately 2.08-2.82 × 10(8)/mL, ∼3.13 µm, 6.89-6.99 and from (78.08% ± 0.57%) to (57.23% ± 0.94%), respectively. Under US exposure, the loaded uPA demonstrated bioactivity by agarose fibrin plate and in vitro thrombolysis of the three uPA-MBs also showed higher effects than in the group of those who received uPA-MBs alone, the control group or the US group. In conclusion, the physiochemical properties of these self-made uPA-MBs are suitable for intravenous administration but 1 uPA-MB and 5 uPA-MBs are better than 10 uPA-MBs. uPA-MBs combined with US can decrease the in vitro dosage of uPA for thrombolysis.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Fibrinolíticos/química , Terapia Trombolítica/métodos , Terapia por Ultrassom/métodos , Ativador de Plasminogênio Tipo Uroquinase/química , Meios de Contraste/administração & dosagem , Meios de Contraste/química , Fibrinolíticos/administração & dosagem , Liofilização , Técnicas In Vitro , Microbolhas , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem
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