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1.
Sensors (Basel) ; 23(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36679601

RESUMO

The paper studies the secrecy communication threatened by a single eavesdropper in Energy Harvesting (EH)-based cognitive radio networks, where both the Secure User (SU) and the jammer harvest, store, and utilize RF energy from the Primary Transmitter (PT). Our main goal is to optimize the time slots for energy harvesting and wireless communication for both the secure user as well as the jammer to maximize the long-term performance of secrecy communication. A multi-agent Deep Reinforcement Learning (DRL) method is proposed for solving the optimization of resource allocation and performance. Specifically, each sub-channel from the Secure Transmitter (ST) to the Secure Receiver (SR) link, along with the jammer to the eavesdropper link, is regarded as an agent, which is responsible for exploring optimal power allocation strategy while a time allocation network is established to obtain optimal EH time allocation strategy. Every agent dynamically interacts with the wireless communication environment. Simulation results demonstrate that the proposed DRL-based resource allocation method outperforms the existing schemes in terms of secrecy rate, convergence speed, and the average number of transition steps.


Assuntos
Comunicação , Alocação de Recursos , Fenômenos Físicos , Simulação por Computador , Cognição
2.
Chin J Integr Med ; 29(3): 233-243, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36094770

RESUMO

OBJECTIVE: To explore the potential mechanism of Yishen Qutong Granules (YSQTG) for the treatment of esophageal cancer using network pharmacology and experimental research. METHODS: The effective components and molecular mechanism of YSQTG in treating esophageal cancer were expounded based on network pharmacology and molecular docking. The key compound was identified by high-performance liquid chromatography and mass spectrometry (HPLC-MS) to verify the malignant phenotype of the key compounds in the treatment of esophageal cancer. Then, the interaction proteins of key compounds were screened by pull-down assay combined with mass spectrometry. RNA-seq was used to screen the differential genes in the treatment of esophageal cancer by key compounds, and the potential mechanism of key compounds on the main therapeutic targets was verified. RESULTS: Totally 76 effective compounds of YSQTG were found, as well as 309 related targets, and 102 drug and disease interaction targets. The drug-compound-target network of YSQTG was constructed, suggesting that quercetin, luteolin, wogonin, kaempferol and baicalein may be the most important compounds, while quercetin had higher degree value and degree centrality, which might be the key compound in YSQTG. The HPLC-MS results also showed the stable presence of quercetin in YSQTG. By establishing a protein interaction network, the main therapeutic targets of YSQTG in treating esophageal cancer were Jun proto-oncogene, interleukin-6, tumor necrosis factor, and RELA proto-oncogene. The results of cell function experiments in vitro showed that quercetin could inhibit proliferation, invasion, and clonal formation of esophageal carcinoma cells. Quercetin mainly affected the biological processes of esophageal cancer cells, such as proliferation, cell cycle, and cell metastasis. A total of 357 quercetin interacting proteins were screened, and 531 genes were significantly changed. Further pathway enrichment analysis showed that quercetin mainly affects the metabolic pathway, MAPK signaling pathway, and nuclear factor kappa B (NF- κ B) signaling pathway, etc. Quercetin, the key compound of YSQTG, had stronger binding activity by molecular docking. Pull-down assay confirmed that NF- κ B was a quercetin-specific interaction protein, and quercetin could significantly reduce the protein level of NF- κ B, the main therapeutic target. CONCLUSION: YSQTG can be multi-component, multi-target, multi-channel treatment of esophageal cancer, it is a potential drug for the treatment of esophageal cancer.


Assuntos
Medicamentos de Ervas Chinesas , Neoplasias Esofágicas , Humanos , Farmacologia em Rede , Quercetina , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular
3.
Front Immunol ; 13: 989972, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389722

RESUMO

Metastatic castration-resistant prostate cancer (CRPC) has long been considered to be associated with patient mortality. Among metastatic organs, bone is the most common metastatic site, with more than 90% of advanced patients developing bone metastases (BMs) before 24 months of death. Although patients were recommended to use bone-targeted drugs represented by bisphosphonates to treat BMs of CRPC, there was no significant improvement in patient survival. In addition, the use of immunotherapy and androgen deprivation therapy is limited due to the immunosuppressed state and resistance to antiandrogen agents in patients with bone metastases. Therefore, it is still essential to develop a safe and effective therapeutic schedule for CRPC patients with BMs. To this end, we propose a multiplex drug repurposing scheme targeting differences in patient immune cell composition. The identified drug candidates were ranked from the perspective of M2 macrophages by integrating transcriptome and network-based analysis. Meanwhile, computational chemistry and clinical trials were used to generate a comprehensive drug candidate list for the BMs of CRPC by drug redundancy structure filtering. In addition to docetaxel, which has been approved for clinical trials, the list includes norethindrone, testosterone, menthol and foretinib. This study provides a new scheme for BMs of CRPC from the perspective of M2 macrophages. It is undeniable that this multiplex drug repurposing scheme specifically for immune cell-related bone metastases can be used for drug screening of any immune-related disease, helping clinicians find promising therapeutic schedules more quickly, and providing reference information for drug R&D and clinical trials.


Assuntos
Neoplasias Ósseas , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Antagonistas de Androgênios/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Transcriptoma , Reposicionamento de Medicamentos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Macrófagos/patologia
4.
Polymers (Basel) ; 14(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36365723

RESUMO

Polymer insulators using silicone rubber materials as sheds and sheaths are widely used in power systems to replace traditional porcelain and glass insulators which are heavy, inconvenient to install, and prone to pollution flashover. However, in recent years, polymer insulators that have been operating in harsh outdoor environments for many years have experienced different degrees of aging. The aging degree and aging products of silicone rubber are the focus of research. Fourier transform infrared spectroscopy (FTIR) is a technical method to analyze the internal molecular bonds and functional groups of materials, and it is often used to study the aging degree and aging products of silicone rubber. In this paper, the aging characteristics of silicone rubber samples in a high altitude area, salt fog environment, and acid environment were studied by FTIR. The results showed that the silicone rubber in a harsh environment, such as strong radiation, salt fog, and acid fog was degraded to some extent, and its main chain was cut off, the degree of polymerization was reduced, and the content of hydrophobic functional groups was reduced. Infrared spectroscopy can be used to analyze the aging phenomenon of polymers.

5.
Biomed Res Int ; 2022: 4931368, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35872837

RESUMO

Bone metastasis is a common complication in patients with advanced tumors, causing pain and bone destruction and affecting their quality of life. Typically, complementary and alternative medicine (CAM), with unique theoretical guidance, has played key roles in the treatment of tumor-related diseases. Gu-tong formula (GTF), as a representative prescription of traditional Chinese medicine, has been demonstrated to be an effective clinical medication for the relief of cancer pain. However, the molecular mechanism of GTF in the treatment of osteolytic metastasis is still unclear. Herein, we employ network pharmacology and molecular dynamics methods to uncover the potential treatment mechanism, indicating that GTF can reduce the levels of serum IL6 and TGFB1 and thus limit the scope of bone cortical damage. Among the active compounds, sesamin and deltoin can bind stably with IL6 and TGFB1, respectively, and have the potential to become anti-inflammatory and anticancer drugs. Although the reasons for the therapeutic effect of GTF are complex and comprehensive, this work provides biological plausibility in the treatment of osteolytic metastases, which has a guiding significance for the treatment of cancer pain with CAM.


Assuntos
Dor do Câncer , Medicamentos de Ervas Chinesas , Osteólise , Dor do Câncer/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Interleucina-6 , Medicina Tradicional Chinesa , Osteólise/induzido quimicamente , Osteólise/tratamento farmacológico , Prescrições , Qualidade de Vida
6.
Zhongguo Zhen Jiu ; 37(4): 355-359, 2017 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-29231584

RESUMO

OBJECTIVE: To observe the effectiveness and safety of electrothermal acupuncture in the prevention and treatment of chemotherapy-induced nausea and vomiting (CINV) in the cancerous patients of phlegm-stasis interaction in cisplatin-containing chemotherapy. METHODS: Sixty cases of phlegm-stasis interaction in cisplatin-containing chemotherapy were randomized into a trial group and a control group, 30 cases in each one. In the control group, the intravenous drip of granisetron hydrochloride injection was adopted, 3 mg before and after cisplatin-containing chemotherapy 30 min, continuously for 3 days. 43 to 45℃ electrothermal acupuncture at zusanli(ST 36) for 30 min was used on the basis of the treatment as the control group in the trial group,once a day for 3 days. CINV, anti-nausea effects, Karnofsky score, the syndrome score of phlegm-stasis interaction, and relevant indices of safety were observed on the 1st and 7th days of cisplatin-containing chemotherapy separately. RESULTS: 1.Regarding CINV and anti-nausea effect, CINV did not occur before chemotherapy in the patients of the two groups. On the 1st and 7th days of chemotherapy, CINV in the trial group were milder than those in the control group (both P<0.05).The anti-nausea effects in the trail group were better than those of the control group.2.Regarding Karnofsky score and the syndrome score of phlegm-stasis interaction, the improvements on the 7th days of chemotherapy in the trial group were better than those in the control group, indicating the significant differences (both P<0.05). 3.Regarding the safety indies, there was no adverse reaction during the treatment in the two groups. CONCLUSIONS: The electrothermal acupuncture effectively relieves CINV, and improves self-care dbility and the symptoms of phlegm-stasis interaction.


Assuntos
Terapia por Acupuntura/métodos , Náusea/terapia , Vômito/terapia , Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Granisetron/uso terapêutico , Humanos , Náusea/induzido quimicamente , Náusea/prevenção & controle , Neoplasias/tratamento farmacológico , Vômito/induzido quimicamente , Vômito/prevenção & controle
7.
J Tradit Chin Med ; 37(1): 30-4, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-29956899

RESUMO

OBJECTIVE: To investigate the effect of Yishengukang decoction on the expression of the metabolic bone markers, bone-specific alkaline phosphatase (BAP), carboxyterminal propeptide of type Ⅰ procollagen (PICP), and arboxyterminal cross-linked telepeptide of type Ⅰ collagen (ICTP), in cancer patients with bone metastasis. METHODS: Patients (n = 180) were divided into three groups: (a) bone metastasis patients treated with Yishengukang and pamidronate disodium injection (treatment group, n = 60); (b) bone metastasis patients treated with pamidronate disodium injection alone (control group, n = 60); (c) cancer patients without metastatic bone lesion (non-bone metastasis group, n = 60). Serum levels of the metabolic markers BAP, PICP, and ICTP were detected by enzyme-linked immunosorbent assay pre- and post-therapy. RESULTS: A significant decrease in serum BAP level was observed in the treatment group compared with the control group. However there were no significant differences in serum levels of PICP and ICTP before or after treatment compared with the control group. CONCLUSION: Yishengukang decoction combined with pamidronate disodium injection reduced serum BAP level to a greater extent that pamidronate disodium injection alone. Furthermore, the combined therapy was more beneficial in regulating imbalanced bone metabolism after bone metastasis, and may represent the molecular mechanism underpinning the effects of Yishengukang decoction.


Assuntos
Fosfatase Alcalina/sangue , Neoplasias Ósseas/sangue , Neoplasias Ósseas/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Neoplasias/complicações , Pró-Colágeno/sangue , Fosfatase Alcalina/genética , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Colágeno/sangue , Colágeno/genética , Colágeno Tipo I/sangue , Colágeno Tipo I/genética , Humanos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/genética , Neoplasias/patologia , Pró-Colágeno/genética
8.
Braz J Microbiol ; 46(2): 455-64, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26273260

RESUMO

Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10(-4) mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments.


Assuntos
Bacillus/isolamento & purificação , Carbonato de Cálcio/metabolismo , Caulobacteraceae/isolamento & purificação , Sedimentos Geológicos/microbiologia , Sporosarcina/isolamento & purificação , Compostos de Amônio/metabolismo , Bacillus/classificação , Bacillus/genética , Bacillus/metabolismo , Caulobacteraceae/classificação , Caulobacteraceae/genética , Caulobacteraceae/metabolismo , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sporosarcina/classificação , Sporosarcina/genética , Sporosarcina/metabolismo , Ureia/metabolismo , Difração de Raios X
9.
Braz. j. microbiol ; 46(2): 455-464, Apr-Jun/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-749744

RESUMO

Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10−4 mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments.


Assuntos
Bacillus/isolamento & purificação , Carbonato de Cálcio/metabolismo , Caulobacteraceae/isolamento & purificação , Sedimentos Geológicos/microbiologia , Sporosarcina/isolamento & purificação , Compostos de Amônio/metabolismo , Bacillus/classificação , Bacillus/genética , Bacillus/metabolismo , Análise por Conglomerados , Caulobacteraceae/classificação , Caulobacteraceae/genética , Caulobacteraceae/metabolismo , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Filogenia , /genética , Análise de Sequência de DNA , Sporosarcina/classificação , Sporosarcina/genética , Sporosarcina/metabolismo , Ureia/metabolismo , Difração de Raios X
10.
Exp Cell Res ; 323(2): 346-51, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24631290

RESUMO

The structure of a tissue engineering scaffold plays an important role in modulating tissue growth. A novel gelatin-chitosan (Gel-Cs) scaffold with a unique structure produced by three-dimensional printing (3DP) technology combining with vacuum freeze-drying has been developed for tissue-engineering applications. The scaffold composed of overall construction, micro-pore, surface morphology, and effective mechanical property. Such a structure meets the essential design criteria of an ideal engineered scaffold. The favorable cell-matrix interaction supports the active biocompatibility of the structure. The structure is capable of supporting cell attachment and proliferation. Cells seeded into this structure tend to maintain phenotypic shape and secreted large amounts of extracellular matrix (ECM) and the cell growth decreased the mechanical properties of scaffold. This novel biodegradable scaffold has potential applications for tissue engineering based upon its unique structure, which acts to support cell growth.


Assuntos
Adipócitos/efeitos dos fármacos , Células-Tronco Adultas/efeitos dos fármacos , Engenharia Tecidual , Alicerces Teciduais/química , Adipócitos/fisiologia , Células-Tronco Adultas/fisiologia , Adesão Celular , Proliferação de Células , Quitosana/farmacologia , Gelatina/farmacologia , Humanos
11.
Braz. j. microbiol ; 44(4): 1001-1007, Oct.-Dec. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-705287

RESUMO

Microbiologically induced deterioration (MID) causes corrosion of concrete by producing acids (including organic and inorganic acids) that degrade concrete components and thus compromise the integrity of sewer pipelines and other structures, creating significant problems worldwide. Understanding of the fundamental corrosion process and the causal agents will help us develop an appropriate strategy to minimize the costs in repairs. This review presents how microorganisms induce the deterioration of concrete, including the organisms involved and their colonization and succession on concrete, the microbial deterioration mechanism, the approaches of studying MID and safeguards against concrete biodeterioration. In addition, the uninvestigated research area of MID is also proposed.


Assuntos
Corrosão , Materiais de Construção/microbiologia , Microbiologia Ambiental , Ácidos/metabolismo
12.
Biosci. j. (Online) ; 29(4): 1000-1006, july/aug. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-946439

RESUMO

The conversion of waste cooking oil into riboflavin by Ashbya gossypii was investigated in this paper. The effect of initial pH and the original volume of added waste cooking oil in the medium were evaluated to optimize the fermentation efficiency. The results show that when the initial pH was adjusted to 6.5 and 40 g/L waste cooking oil was added in the medium, no residual waste cooking oil was observed and the riboflavin yield reached 4.78 g/L. During the fermentation process, pH, biomass, free amino nitrogen and reduced sugar were dynamically monitored to evaluate the efficient utilization of waste cooking oil for riboflavin yield. The results show that when pH was kept in the range of 6.5-6.8 during the fermentation process, the levels of free amino nitrogen and reduced sugar could be used more efficiently and the riboflavin yield increased to 6.76 g/L .


A conversão microbiana de óleo de cozinha recolhido em riboflavina por Ashbya gossypii foi investigada nesse estudo. O efeito inicial do pH e o volume original de óleo de cozinha recolhido foram avaliados para otimizar a eficiência de fermentação. Os resultados mostraram que quando o pH inicial foi ajustado para 6.5 e 0g/l de óleo de cozinha adicionado ao meio, nenhum óleo residual foi observado e a riboflavina pura atingiu 4.78g/L. Durante o processo de fermentação, pH, biomassa, amino nitrogênio livre e açúcar reduzido foram monitorados dinamicamente para avaliar a utilização eficiente do óleo de cozinha recolhido por riboflavina. Os resultados mostram que quando o pH é mantido numa amplitude de 6.5-6-8 durante o processo de fermentação, os níveis de amino nitrogênio livres e açúcar reduzido podem ser usados mais eficientemente e a riboflavina pura chega a 6.76 g/L.


Assuntos
Riboflavina , Óleos de Plantas , Poluição Ambiental
13.
Braz J Microbiol ; 44(4): 1001-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24688488

RESUMO

Microbiologically induced deterioration (MID) causes corrosion of concrete by producing acids (including organic and inorganic acids) that degrade concrete components and thus compromise the integrity of sewer pipelines and other structures, creating significant problems worldwide. Understanding of the fundamental corrosion process and the causal agents will help us develop an appropriate strategy to minimize the costs in repairs. This review presents how microorganisms induce the deterioration of concrete, including the organisms involved and their colonization and succession on concrete, the microbial deterioration mechanism, the approaches of studying MID and safeguards against concrete biodeterioration. In addition, the uninvestigated research area of MID is also proposed.


Assuntos
Materiais de Construção/microbiologia , Corrosão , Microbiologia Ambiental , Ácidos/metabolismo
14.
Braz. j. microbiol ; 43(2): 441-448, Apr.-June 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-644457

RESUMO

The use of the filamentous fungus, Ashbya gossypii, to improve riboflavin production at an industrial scale is described in this paper. A riboflavin overproducing strain was isolated by ultraviolet irradiation. Ten minutes after spore suspensions of A. gossypii were irradiated by ultraviolet light, a survival rate of 5.5% spores was observed, with 10% of the surviving spores giving rise to riboflavin-overproducing mutants. At this time point, a stable mutant of the wild strain was isolated. Riboflavin production of the mutant was two fold higher than that of the wild strain in flask culture. When the mutant was growing on the optimized medium, maximum riboflavin production could reach 6.38 g/l. It has even greater promise to increase its riboflavin production through dynamic analysis of its growth phase parameters, and riboflavin production could reach 8.12 g/l with pH was adjusted to the range of 6.0-7.0 using KH2PO4 in the later growth phase. This mutant has the potential to be used for industrial scale riboflavin production.


Assuntos
Esporos Fúngicos/isolamento & purificação , Fungos/genética , Fungos/isolamento & purificação , Riboflavina/isolamento & purificação , Crescimento , Métodos , Otimização de Processos , Padrões de Referência
15.
Braz J Microbiol ; 43(2): 441-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031850

RESUMO

The use of the filamentous fungus, Ashbya gossypii, to improve riboflavin production at an industrial scale is described in this paper. A riboflavin overproducing strain was isolated by ultraviolet irradiation. Ten minutes after spore suspensions of A. gossypii were irradiated by ultraviolet light, a survival rate of 5.5% spores was observed, with 10% of the surviving spores giving rise to riboflavin-overproducing mutants. At this time point, a stable mutant of the wild strain was isolated. Riboflavin production of the mutant was two fold higher than that of the wild strain in flask culture. When the mutant was growing on the optimized medium, maximum riboflavin production could reach 6.38 g/l. It has even greater promise to increase its riboflavin production through dynamic analysis of its growth phase parameters, and riboflavin production could reach 8.12 g/l with pH was adjusted to the range of 6.0-7.0 using KH2PO4 in the later growth phase. This mutant has the potential to be used for industrial scale riboflavin production.

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