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1.
J Contam Hydrol ; 261: 104287, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38219283

RESUMO

Semi-arid rivers are particularly vulnerable and responsive to the impacts of industrial contamination. Prompt identification and projection of pollutant dynamics are crucial in the accidental pollution incidents, therefore required the timely informed and effective management strategies. In this study, we collected water quality monitoring data from a typical semi-arid river. By water quality inter-correlation mapping, we identified the regularity and abnormal fluctuations of pollutant discharges. Combining the association rule method (Apriori) and characterized pollutants of different industries, we tracked major industrial pollution sources in the Dahei River Basin. Meanwhile, we deployed the integrated multivariate long and short-term memory network (LSTM) to forecast principal contaminants. Our findings revealed that (1) biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen, total phosphorus, and ammonia nitrogen exhibited high inter-correlations in water quality mapping, with lead and cadmium also demonstrating a strong association; (2) The main point sources of contaminant were coking, metal mining, and smelting industries. The government should strengthen the regulation and control of these industries and prevent further pollution of the river; (3) We confirmed 4 key pollutants: COD, ammonia nitrogen, total nitrogen, and total phosphorus. Our study accurately predicted the future changes in this water quality index. The best results were obtained when the prediction period was 1 day. The prediction accuracies reached 85.85%, 47.15%, 85.66%, and 89.07%, respectively. In essence, this research developed effective water quality traceability and predictive analysis methods in semi-arid river basins. It provided an effective tool for water quality surveillance in semi-arid river basins and imparts a scientific scaffold for the environmental stewardship endeavors of pertinent authorities.


Assuntos
Aprendizado Profundo , Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Amônia/análise , Poluentes Químicos da Água/análise , Rios/química , Nitrogênio/análise , Fósforo , China , Poluição da Água/análise
2.
J Sep Sci ; 47(1): e2300606, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38095460

RESUMO

QiXueShuFu Decoction (QXSFD) modified from the Bazhen Decoction which was originally from the classic Ming Dynasty is a traditional folk formula that boosts the body's immune system. However, its ambiguous chemical components limited its quality control evaluation. In this study, ultra-performance liquid chromatography (UPLC) fingerprint combined with multivariate analysis was used to evaluate the quality of 15 batches of QXSFD, and UPLC quadrupole-orbitrap mass spectrometry was used to further examine the chemical components in QXSFD, after which representative compounds from each disassembled prescription were selected for comparison. Fifteen batches of samples had 33 common peaks in which 11 differential components could be used as a reference for subsequent quality control. One hundred forty-three components were identified from QXSFD. Saponins were mainly derived from the monarch, terpenes from the minister, and polysaccharides and glycosides from the assistant. In addition, quantitative assay revealed that the content of ferulic acid, chlorogenic acid, 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucoside and 3,6'-disinapoyl sucrose in the whole prescription were higher than the contents of each disassembled prescription. This is the first comprehensive quality report on the chemical components of QXSFD, which is important for pharmacodynamic material basis and quality control.


Assuntos
Medicamentos de Ervas Chinesas , Saponinas , Medicamentos de Ervas Chinesas/análise , Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos , Saponinas/análise , Espectrometria de Massa com Cromatografia Líquida
3.
Transl Stroke Res ; 14(5): 667-677, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35907128

RESUMO

The objective of this study is to explore whether craniocervical manual lymphatic drainage (cMLD) can promote hematoma absorption and increase the efficiency of atorvastatin-based conservative treatment in chronic subdural hematoma (CSDH) patients. All CSDH patients treated with atorvastatin-based therapy between October 2020 and February 2022 in our department were retrospectively screened for enrollment. The patients were divided into the control and cMLD groups according to whether cMLD was performed. Head CT or MR images in both groups were obtained before the treatment and 2 weeks and 4 weeks after the treatment. MR images of the deep cervical lymphatic nodes (dCLNs) in 23 patients were obtained in the cMLD group before and approximately 2 weeks after treatment. The volumes of the dCLNs and hematoma were calculated. The primary outcomes are the differences in hematoma volume reduction after 4 weeks of treatment. The secondary outcomes were (1) the differences in hematoma volume reduction between the patients in these two groups in the 2nd week, (2) the dCLN volume change in the cMLD group before and after 2 weeks of treatment, and (3) the percentage of patients who transitioned to surgery because of failure to the conservative treatment. A total of 106 consecutive patients were enrolled in this study for analysis; 54 patients received atorvastatin-based treatment (control group), and 52 were treated with both atorvastatin-based treatment and cMLD (cMLD group). At baseline, the mean hematoma volume was 76.53 ± 42.97 ml in the control group and 88.57 ± 49.01 ml in the cMLD group (p = 0.181). In the 4th week, the absolute number of hematoma reductions (20.79 ± 34.73 ml vs. 37.28 ± 28.24 ml, p = 0.009) and percentage of hematoma reductions (22.58% ± 60.01% vs. 46.43% ± 30.12%, p = 0.012) in the cMLD group were greater than those in the control group. After 2 weeks of treatment, the absolute number of hematoma reductions showed no difference in the two groups, while the percentage of hematoma reduction was higher in the cMLD group (18.18% ± 24.61% vs. 2.08% ± 25.72%, p = 0.001). One patient in cMLD and 8 patients in the control group were transitioned to receive surgical treatment. The dCLN volumes in 23 experimental patients increased significantly after 2 weeks of treatment in the cMLD group (p = 0.032). There were no severe side effects that needed to be reported. Combined with atorvastatin-based therapy, cMLD can promote hematoma absorption and decrease the surgery rate, which provides a new therapeutic strategy for CSDH.


Assuntos
Hematoma Subdural Crônico , Humanos , Atorvastatina/uso terapêutico , Atorvastatina/efeitos adversos , Hematoma Subdural Crônico/diagnóstico por imagem , Hematoma Subdural Crônico/tratamento farmacológico , Hematoma Subdural Crônico/cirurgia , Estudos Retrospectivos , Drenagem Linfática Manual , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Oxid Med Cell Longev ; 2022: 1755608, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36578522

RESUMO

Ulcerative colitis (UC) is a multifactor intestinal disease with increased morbidity. Recently, pleiotropic drugs with exact biosafety have been urgently needed. Honokiol (HKL) is the major bioactive component of traditional Chinese medicine "Houpu," with almost no toxic effects and approved anti-inflammation, antioxidant, antispasmodic, etc. effects. This study examined the therapeutic effect of HKL in dextran sulfate sodium- (DSS-) induced experimental colitis. In vivo, C57BL/6 mice received 3% DSS for seven days to generate UC, and HKL was pretreated for five days and given during the whole DSS-induced period. In vitro, RAW264.7 macrophages were stimulated with lipopolysaccharide (LPS) to induce inflammation, and mouse colon epithelial cells (MCEC) were treated with HKL or pretreated with HKL and then stimulated with LPS-induced macrophage supernate to investigate the barrier enhancement roles. HKL significantly ameliorated disease activity index (DAI), colon length, and histopathological scores in DSS-induced colitis. The inflammatory mediators of interleukin 1ß (IL-1ß), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX2) were decreased, and the tight conjunction proteins were increased in the HKL-treated group both in vivo and in vitro. Above all, HKL can relieve experimental UC through anti-inflammation, antioxidant, and epithelial barrier enhancement roles. These effects were associated with peroxisome proliferator-activated receptor γ (PPARγ)/nuclear factor-κB (NF-κB) p65, sirtuin3 (SIRT3)/adenosine 5'-monophosphate- (AMP-) activated protein kinase (AMPK), and nuclear factor erythroid 2-related factor 2 (NRF2)/heme oxygenase 1 (HO1) signaling pathways. In conclusion, after further clinical studies, HKL may be a promising drug for UC.


Assuntos
Colite Ulcerativa , Colite , Animais , Camundongos , Lipopolissacarídeos/efeitos adversos , Antioxidantes/metabolismo , Camundongos Endogâmicos C57BL , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Inflamação/patologia , Colite Ulcerativa/induzido quimicamente , Colo , NF-kappa B/metabolismo , Anti-Inflamatórios/efeitos adversos , Interleucina-6/metabolismo , Estresse Oxidativo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças
5.
Breastfeed Med ; 17(11): 940-946, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36378822

RESUMO

Background: The microbial community in human milk is associated with many maternal and neonatal factors. This study aimed to investigate the effect of antibiotic exposure on the microbial community structure of colostrum. Methods: Twenty women with antibiotic treatment immediately after delivery and 10 age-matched control women were enrolled at the Guangdong Women and Children Hospital. Colostrum samples were collected within postpartum 30 hours. The V4 variable region of the bacterial 16S rRNA gene was sequenced to characterize the microbial profile using Illumina MiSeq platform. Results: Phyla Proteobacteria and Firmicutes were the predominant bacteria in colostrum samples. The core and abundant genera in colostrum included Streptococcus, Staphylococcus, and Pseudomonas. Compared with the control group, principal coordinate analysis based on the Bray-Curtis distance showed a significant difference in milk microbial community in women with antibiotic exposure, accompanied by a significantly lower alpha diversity and a different microbial ecological network. Furthermore, the relative abundances of genera Actinomyces, Anaerobacter, and Clostridium_sensu_stricto significantly decreased after antibiotic treatment. Conclusions: This study provided evidence of alterations in the colostrum microbial community with antibiotic exposure, improving our understanding of the effects of antibiotic treatment on the milk microbiome.


Assuntos
Colostro , Microbiota , Gravidez , Recém-Nascido , Criança , Feminino , Humanos , RNA Ribossômico 16S/genética , Antibacterianos/uso terapêutico , Aleitamento Materno , Leite Humano/microbiologia
6.
J Am Chem Soc ; 144(45): 20825-20833, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36318653

RESUMO

Thioredoxin reductase (TrxR) is highly overexpressed in cancer cells to promote malignant tumor survival. Designing drugs that inhibit TrxR activity is a promising approach to achieve highly effective cancer chemotherapy. However, the selectivity of TrxR inhibitors continue to be a challenge for scientists. In this work, we demonstrate a new strategy to selectively inhibit TrxR through constructing electrophilic center -N-Se(δ+)-N- by using the polarization effect of the selenium atom. The constructed electrophilic center interacts noncovalently with the active motif of TrxR to avoid the interference of other residues in human tissues, thereby selectively inhibiting intracellular TrxR activity. Computational and experimental analysis confirms that the formed electrophilic selenium center preferred to attack the SeC residues in the redox active center of TrxR at the 498 site through strong noncovalent interactions. Both in vitro and in vivo experimental results confirmed that this strategy can significantly improve the anticancer effect. This study may provide a novel route to design highly effective and selective chemotherapeutic drugs.


Assuntos
Neoplasias , Selênio , Humanos , Tiorredoxina Dissulfeto Redutase , Selênio/farmacologia , Neoplasias/tratamento farmacológico , Oxirredução , Antioxidantes
7.
Small ; 18(34): e2202728, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35796192

RESUMO

Cancer phototherapy activates immunogenic cell death (ICD) and elicits a systemic antitumor immune response, which is an emerging approach for tumor treatment. Most available photosensitizers require a combination of immune adjuvants or checkpoint inhibitors to trigger antitumor immunity because of the immunosuppressive tumor microenvironment and the limited phototherapeutic effect. A class of tumor-targeting heptamethine cyanine photosensitizers modified with an endoplasmic reticulum (ER)-targeting group (benzenesulfonamide) are synthesized. Phototherapy of tumor cells markedly amplifies ER stress and promotes tumor antigen release, as the ER is required for protein synthesis, secretion, and transport. More importantly, different electron-donating or -withdrawing substitutions are introduced into benzenesulfonamide to modulate the nonradiative decay pathways through intramolecular charge transfer, including singlet-triplet intersystem crossing (photodynamic effect) and internal thermal conversion (photothermal effect). Thus, a heptamethine cyanine photosensitizer containing a binitro-substituted benzenesulfonamide (ER-Cy-poNO2 ) is identified that preferentially accumulates in the ER of tumor cells. It significantly enhances the phototherapeutic effect by inducing excessive ER stress and robust ICD. Consequently, this small molecular photosensitizer triggers a sufficient antitumor immune response and effectively suppresses the growth of both primary and distant metastatic tumors, whereas no apparent toxicity is observed. This heptamethine cyanine photosensitizer has the potential to enhance cancer-targeted immunotherapy.


Assuntos
Neoplasias , Fotoquimioterapia , Linhagem Celular Tumoral , Corantes , Estresse do Retículo Endoplasmático , Humanos , Imunoterapia , Neoplasias/terapia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia , Microambiente Tumoral
8.
Theranostics ; 12(8): 3882-3895, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35664065

RESUMO

Rationale: Acute kidney injury (AKI) is a common critical illness in the clinic and currently lacks effective treatment options. Ischemia reperfusion injury (IRI) is a major pathogenic factor for AKI. Due to the deficiency of selenium (Se) in AKI patients, we intended to treat IRI-induced AKI using a Se rebalancing strategy in the present study. Methods: Sodium selenate, ascorbic acid, and bovine serum albumin (BSA) were employed to prepare nanomaterials termed Se@BSA nanoparticles (NPs) using a simple method. Experiments with human renal tubular epithelial HK-2 cells exposed to hypoxia/reoxygenation (H/R) and IRI-AKI mice were used to evaluate the therapeutic efficiency of Se@BSA NPs. Transcriptome sequencing, further molecular biology experiments, and pathologic analysis were performed to investigate the underlying mechanisms. Results: Se@BSA NPs accumulated in mouse kidneys and could be endocytosed by renal tubular epithelial cells after intravenous administration. In vitro studies showed that Se@BSA NP treatment markedly increased the levels of glutathione peroxidase (GPx)-1 and suppressed NLRP3 inflammasome activation in H/R cells, which resulted in reductions in the proteolytic cleavage of pro-Caspase-1 into active Caspase-1 and the maturation of inflammatory factors. Mouse experiments confirmed these findings and demonstrated an inspiring mitigative effect of Se@BSA NPs on IRI-induced AKI. Owing to modulation of the GPx-1/NLRP3/Caspase-1 pathway, Se@BSA NPs dramatically inhibited fibrosis formation after AKI. Conclusion: This study provides an effective therapeutic option by applying easy-to-produce Se-containing nanomaterials to remedy Se imbalance and impede inflammatory responses in the kidney, which is a promising candidate for AKI treatment.


Assuntos
Injúria Renal Aguda , Nanopartículas , Traumatismo por Reperfusão , Selênio , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Animais , Apoptose , Caspases/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Rim/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Traumatismo por Reperfusão/metabolismo , Selênio/farmacologia , Selênio/uso terapêutico
9.
Interdiscip Sci ; 14(1): 55-63, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34510373

RESUMO

The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide for almost 2 years. It starts from viral adherence to host cells through an interaction between spike glycoprotein 1 (S1) containing a receptor-binding domain (RBD) and human angiotensin-converting enzyme-2 (ACE2). One of the useful strategies to prevent SARS-CoV-2 infection is to inhibit the attachment of RBD to ACE2. Therefore, the current work proposed potent peptides against SARS-CoV-2 infection by carrying out MM-PBSA calculation based on the binding of 52 antiviral peptides (AVPs) to RBD. Considering the binding free energies of AVPs to RBD, cyanovirin-N (CV-N) showed the strongest RBD binding affinity among 52 AVPs. Upon structural analysis of RBD complex with CV-N, it was observed that 12 of the 13 key residues of RBD binding to ACE2 were hijacked by CV-N. CV-N bound to RBD at a smaller affinity of 14.9 nM than that of ACE2 and inhibited the recruitment of S1 to human alveolar epithelial cells. Further analysis revealed that CV-N suppressed SARS-CoV-2 S pseudovirion infection with a half-maximal inhibitory concentration (IC50) of 18.52 µg/mL. This study demonstrated a drug screening for AVPs against SARS-CoV-2 and discovered a peptide with inspiring antiviral properties, which provided a promising strategy for the COVID-19 therapeutic approach.


Assuntos
Produtos Biológicos , Tratamento Farmacológico da COVID-19 , Produtos Biológicos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Ligação Proteica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo
10.
Free Radic Biol Med ; 174: 144-156, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34389464

RESUMO

Ionizing radiation (IR)-induced excessive reactive oxygen species (ROS) is an important contributor of the injury of hematopoietic system. Grape seed proanthocyanidin extract (GSPE) is a new type of antioxidant, whereas whether it could ameliorate IR-induced hematopoietic injury remains unclear. Here, we show that GSPE treatment improves the survival of irradiated mice and alleviates IR-induced myelosuppression. Meanwhile, the hematopoietic reconstituting ability of hematopoietic stem cells (HSCs) in mice following irradiation exposure is significantly increased after GSPE treatment. Furthermore, GSPE treatment can reduce IR-induced ROS production and relieve DNA damage and apoptosis in hematopoietic stem progenitor cells (HSPCs). Interestingly, we find that a critical antioxidant-associated gene fokhead box transcription factor O1 (Foxo1) is significantly decreased in HSPCs after irradiation. Consistently, hematopoietic specific deletion of Foxo1 increases the radiosensitivity of mice. Further investigations reveal that GSPE treatment specifically upregulates the expression of Foxo1, as well as its target genes superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2) and catalase (CAT). Importantly, Foxo1 deficiency largely abolishes the radioprotection of GSPE on HSPCs. Collectively, our data demonstrate that GSPE plays an important role in ameliorating IR-induced HSPC injury via the Foxo1-mediated pathway. Therefore, GSPE may be used as a promising radioprotective agent.


Assuntos
Extrato de Sementes de Uva , Proantocianidinas , Animais , Antioxidantes/farmacologia , Proteína Forkhead Box O1/genética , Extrato de Sementes de Uva/farmacologia , Células-Tronco Hematopoéticas , Camundongos , Proantocianidinas/farmacologia , Radiação Ionizante
11.
Biochem Biophys Res Commun ; 533(4): 1338-1346, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33059918

RESUMO

The mechanisms underlying the antidepressant activity of quercetin are unknown. We investigated the effect of a quercetin-enriched diet (2 g/kg and 0.5 g/kg doses) on chronic social defeat stress (CSDS)-induced depressive-like behaviors in mice. The 2 g/kg quercetin-enriched diet attenuated depressive-like behaviors when introduced before CSDS (long-term). The long-term 0.5 g/kg quercetin-enriched diet showed a trend toward behavioral improvement. The frequencies of spontaneous excitatory postsynaptic currents (sEPSCs) and spontaneous inhibitory postsynaptic currents (sIPSCs) in the mPFC and hippocampus were significantly higher in mice fed the long-term 2 g/kg quercetin-enriched diet compared with the normal diet; no difference was found in the amygdala. Quercetin-enriched diets administered concurrently and after stress induction failed to trigger these effects. A1-specific astrocyte reactivity was markedly suppressed in the microglia and astrocytes isolated from the mPFC and hippocampus of mice fed the long-term quercetin-enriched diet, but not in those who received quercetin supplementation concurrently or after CSDS. To confirm the role of astrocytes in the neuroprotective effect of quercetin, we activated astrocytes by injecting a chemogenic AAV stimulus into the mPFC and hippocampus and found that astrocyte activation during administration of the long-term quercetin-enriched diet significantly deceased the frequency of sEPSCs and sIPSCs in the mPFC and hippocampus and further attenuated quercetin-induced behavioral improvements. These findings highlight the key role of astrocyte reactivation in the regulation of quercetin neuroprotective activity and suggest that a diet high in quercetin, whether as a fruit- and vegetable-rich diet or food additive may help cope with stress.


Assuntos
Astrócitos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Quercetina/farmacologia , Estresse Psicológico/tratamento farmacológico , Animais , Antidepressivos/administração & dosagem , Antidepressivos/farmacologia , Astrócitos/fisiologia , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Depressão/etiologia , Suplementos Nutricionais , Modelos Animais de Doenças , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Camundongos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/efeitos dos fármacos , Quercetina/administração & dosagem , Estresse Psicológico/patologia
12.
J Nanobiotechnology ; 18(1): 101, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32690018

RESUMO

BACKGROUND: Cell membrane-based nanocarriers are promising candidates for delivering antitumor agents. The employment of a simple and feasible method to improve the tumor-targeting abilities of these systems is appealing for further application. Herein, we prepared a platelet membrane (PM)-camouflaged antitumor nanoparticle. The effects of irradiation pretreatment on tumor targeting of the nanomaterial and on its antitumor action were evaluated. RESULTS: The biomimetic nanomaterial constructed by indocyanine green, poly(d,l-lactide-co-glycolide), and PM is termed PINPs@PM. A 4-Gy X-ray irradiation increased the proportions of G2/M phase and Caveolin-1 content in 4T1 breast cancer cells, contributing to an endocytic enhancement of PINPs@PM. PINPs@PM produced hyperthermia and reactive oxygen species upon excitation by near-infrared irradiation, which were detrimental to the cytoplasmic lysosome and resulted in cell death. Irradiation pretreatment thus strengthened the antitumor activity of PINPs@PM in vitro. Mice experiments revealed that irradiation enhanced the tumor targeting capability of PINPs@PM in vivo. When the same dose of PINPs@PM was intravenously administered, irradiated mice had a better outcome than did mice without X-ray pretreatment. CONCLUSION: The study demonstrates an effective strategy combining irradiation pretreatment and PM camouflage to deliver antitumor nanoparticles, which may be instrumental for targeted tumor therapy.


Assuntos
Antineoplásicos , Plaquetas/citologia , Membrana Celular/química , Portadores de Fármacos/química , Nanopartículas , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/efeitos da radiação , Linhagem Celular , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/efeitos da radiação , Neoplasias Experimentais/patologia , Fototerapia , Raios X
13.
Biomater Sci ; 7(8): 3450-3459, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31268067

RESUMO

Bismuth-containing nanoparticles (BNPs) are potential enhancers for tumor radiotherapy. Improving the bioavailability and developing synergistic therapeutic regimens benefit the drug transformation of BNPs. In the present study, we prepare a mesoporous silica-coated bismuth nanorod (BMSNR) camouflaged by a platelet membrane (PM). This biomimetic material is termed BMSNR@PM. The PM camouflage enhances the immune escape of the BMSNRs by lowering endocytosis by macrophages in the reticuloendothelial system. Additionally, the PM camouflage strengthens the material tumor-targeting capacity and leads to better radiotherapeutic efficacy compared with bare BMSNRs. Owing to the photothermal effect, BMSNR@PMs alters the cell cycle of 4T1 cancer cells post-treatment with 808 nm near-infrared irradiation (NIR). The proportions of S phase and G2/M phase cells decrease and increase, respectively, which explains the synergistic effect of NIR on BMSNR@PM-based radiotherapy. BMSNR@PMs efficiently eradicates cancer cells by the combined action of photothermal therapy (PTT) and radiotherapy in vivo and markedly improves the survival of 4T1-tumor-bearing mice. The synergistic therapeutic effect is superior to the outcomes of PTT and radiotherapy performed alone. Our study demonstrates a versatile bismuth-containing nanoplatform with tumor-targeting, immune escape, and radiosensitizing functionalities using an autologous cell membrane biomimetic concept that may promote the development of radiotherapy enhancers.


Assuntos
Bismuto/química , Bismuto/farmacologia , Plaquetas/citologia , Neoplasias da Mama/terapia , Membrana Celular/metabolismo , Nanotubos/química , Fototerapia , Sulfetos/química , Sulfetos/farmacologia , Animais , Bismuto/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Linhagem Celular Tumoral , Terapia Combinada , Endocitose , Feminino , Humanos , Macrófagos/metabolismo , Camundongos , Nanocompostos/química , Porosidade , Células RAW 264.7 , Radiossensibilizantes/química , Radiossensibilizantes/metabolismo , Radiossensibilizantes/farmacologia , Dióxido de Silício/química , Sulfetos/metabolismo
14.
Biosens Bioelectron ; 133: 223-229, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30951982

RESUMO

For the first time, a quantitative photothermal-sensing immunochromatographic sensor (PT-ICS) is described using Au nanoparticle-enhanced two-dimensional black phosphorus (BP-Au) as signal component for the photothermal-sensing antibody probe. BP-Au has good photothermal properties at 808 nm, and the photothermal conversion efficiency of the BP-Au nanosheet increased by 12.9% over the black phosphorus nanosheet alone. In addition, the antibody was more easily coupled to this nanosheet due to the good physical adsorption capacity of Au nanoparticles. We used this PT-ICS to detect veterinary antibiotics enrofloxacin (ENR), the photothermal-sensing antibody probe was competitive captured by ENR target and antigen coating on test (T) lines of the sensor. This process was exothermic under an 808 nm laser, and the thermal energy decreased as the ENR in the sample increased. This thermal energy was recorded by an infrared thermal imager or an infrared thermometer, and the concentration of the ENR residues in animal-derived foods was obtained by analyzing the temperature changes in T-lines. Under optimal conditions, the PT-ICS exhibited sensitive and specific detection of ENR from 0.03 µg/L to 10 µg/L with detection limits of 0.023 µg/L. The results agreed well with a commercial enzyme-linked-immunosorbent assay kit. This PT-ICS provided a promising strategy for the detection of ENR residues in animal-derived foods and expected to be used for the detection of other highly sensitive biomacromolecules.


Assuntos
Técnicas Biossensoriais , Cromatografia de Afinidade , Enrofloxacina/isolamento & purificação , Fósforo/química , Animais , Anticorpos/química , Anticorpos/imunologia , Enrofloxacina/química , Ensaio de Imunoadsorção Enzimática , Análise de Alimentos , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química
15.
Sci Rep ; 7(1): 18023, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29269783

RESUMO

The uplift of the Tibetan Plateau (TP) significantly affected both regional and global climates. Although there is evidence that the Tibetan Plateau experienced uplift during the Quaternary, the timing and amplitude are poorly constrained. However, the increased availability of long sedimentary records of vegetation change provides an opportunity to reconstruct the timing of the uplift. Here, we present a well-dated, high-resolution pollen record for the last 2.6 Ma from the Yinchuan Basin, which was incised by the Yellow River with its source in the northeastern Tibetan Plateau. Variations in the Artemisia/Chenopodiaceae (A/C) ratio of the reveal changes in moisture conditions in the Yinchuan Basin during glacial-interglacial cycles, as well as a gradual long-term aridification trend which is consistent with progressive global cooling. However, fluctuations in the percentages of Picea and Abies differ from those of the A/C ratio and we propose that they reflect changes in the vegetation and environment of high elevation areas. The Picea and Abies records reveal two phases of increased representation, at 2.1 and 1.2 Ma, which may indicate phases in the uplift of the northeastern Tibetan Plateau. Thus, they provide independent evidence for the timing of the uplift of the Tibetan Plateau during the Quaternary.


Assuntos
Clima , Fenômenos Geológicos , Pólen , China , Tibet
16.
Mol Med Rep ; 14(4): 3381-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27572472

RESUMO

Increased mesangial cell proliferation is a major pathological feature of early-stage diabetic nephropathy (DN). The present study investigated the effects of the Traditional Chinese Medicine Shenkang injection (SKI) and its main component emodin (EM) on high glucose­cultured mesangial cells. The proliferation rate, cell cycle distribution, apoptosis and morphology of rat renal mesangial cells (RMCs) cultured in the presence of various concentrations of glucose (5.6 or 25 mM), SKI (25, 50 or 100 mg/l) or EM (10, 20 or 40 µM) were assessed at time­points of 12, 24 or 48 h. High­glucose treatment promoted the proliferation of RMCs, which was significantly inhibited by SKI and EM, while these drugs had no effect on RMCs under normal glucose conditions, as indicated by an MTT assay. Furthermore, flow cytometric analysis revealed that SKI and EM inhibited the cell cycle progression of RMCs and induced apoptosis. Transmission electron microscopy revealed morphological characteristics of apoptosis and western blot analysis demonstrated the upregulation of B­cell lymphoma 2­associated X protein (bax) and activation of caspases in RMCs following treatment with SKI or EM under high­glucose conditions. In conclusion, SKI and its major active component EM were shown to inhibit high­glucose­induced proliferation of RMCs via inducing cell cycle arrest at G1 phase as well as cellular apoptosis via upregulation of pro­apoptotic mediators bax and caspase activation, and may therefore be suitable for the treatment of DN.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Emodina/farmacologia , Glucose/metabolismo , Células Mesangiais/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Emodina/administração & dosagem , Injeções , Células Mesangiais/citologia , Células Mesangiais/metabolismo , Ratos
17.
J Med Chem ; 58(7): 3083-93, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25782105

RESUMO

Human defensin 5 (HD5) is a broad-spectrum antibacterial peptide with a C-terminal active region. To promote the development of this peptide into an antibiotic, we initially substituted Glu21 with Arg because it is an electronegative residue located around the active region. Although detrimental to dimer formation, the E21R substitution markedly enhanced the antibacterial activity of HD5 and increased its ability to penetrate cell membranes, demonstrating that increasing the electropositive charge compensated for the effect of dimer disruption. Subsequently, a partial Arg scanning mutagenesis was performed, and Thr7 was selected for replacement with Arg to further strengthen the antibacterial activity. The newly designed peptide, T7E21R-HD5, exhibited potent antibacterial activity, even in saline and serum solutions. In contrast to monomeric E21R-HD5, T7E21R-HD5 assembled into an atypical dimer with parallel ß strands, thus expanding the role of increasing electropositive charge in bactericidal activity and providing a useful guide for further defensin-derived antibiotic design.


Assuntos
Antibacterianos/química , Antibacterianos/farmacocinética , Peptídeos/química , alfa-Defensinas/química , Animais , Antibacterianos/síntese química , Arginina , Domínio Catalítico , Cristalografia por Raios X , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Camundongos , Modelos Moleculares , Peptídeos/síntese química , Peptídeos/genética , Peptídeos/farmacologia , Conformação Proteica , Multimerização Proteica , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , alfa-Defensinas/metabolismo , alfa-Defensinas/farmacologia
18.
Mol Cell Endocrinol ; 402: 13-20, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25540919

RESUMO

Resveratrol (RSV) is reported to have renoprotective activity against diabetic nephropathy, while the mechanisms underlying its function have not been fully elucidated. In this study, we investigate the effect and related mechanism of RSV against high glucose-induced epithelial to mesenchymal transition (EMT) in human tubular epithelial cells (HK-2). A typical EMT is induced by high glucose in HK-2 cells, accompanied by increased levels of reactive oxygen species (ROS). RSV exhibits a strong ability to inhibit high glucose-induced EMT by decreasing intracellular ROS levels via down-regulation of NADPH oxidase subunits NOX1 and NOX4. The activation of extracellular signal-regulated kinase (ERK1/2) is found to be involved in high glucose-induced EMT in HK-2 cells. RSV, like NADPH oxidase inhibitor diphenyleneiodonium, can block ERK1/2 activation induced by high glucose. Our results demonstrate that RSV is a potent agent against high glucose-induced EMT in renal tubular cells via inhibition of NADPH oxidase/ROS/ERK1/2 pathway.


Assuntos
Antioxidantes/farmacologia , Células Epiteliais/fisiologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Estilbenos/farmacologia , Linhagem Celular , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Avaliação Pré-Clínica de Medicamentos , Glucose/fisiologia , Humanos , Rim , Túbulos Renais/patologia , Sistema de Sinalização das MAP Quinases , NADPH Oxidase 1 , NADPH Oxidase 4 , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Resveratrol
19.
Neuroimage ; 81: 199-204, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23684879

RESUMO

The oxytocin receptor gene (OXTR) rs53576A has been associated with autism spectrum disorders (ASDs). A smaller hypothalamic volume has been reported in healthy male A-allele carriers than in male GG homozygotes and in patients with ASDs than in healthy controls. These findings prompt the hypothesis that male AA homozygotes may have weaker hypothalamic functional connectivity when compared to male G-allele carriers. We calculated local functional connectivity density (FCD) using a voxel-wise data-driven approach based on resting-state functional MRI data in 270 young healthy subjects. Both the main effect of genotype and the gender-by-genotype interaction were considered. Of the whole brain, only the local FCD of the hypothalamus exhibited the main effect of genotype. Post-hoc testing revealed significantly lower local FCD in male AA homozygotes compared to male G-allele carriers although there was only a trend of significance in the gender-by-genotype interaction. We further analyzed the resting-state functional connectivity (rsFC) of the hypothalamic region that demonstrating significant genotype differences in local FCD. We found a significant gender-by-genotype interaction in rsFC between the hypothalamic region and the left dorsolateral prefrontal cortex, but no significant main effect of genotype was found. Post-hoc testing revealed that this rsFC was significantly weaker in male AA homozygotes compared to male G-allele carriers. Our findings identify gender-dependent mechanisms of OXTR rs53576 gene variation impacting the functional connectivity of the hypothalamus in healthy individuals and suggest that these mechanisms are important for understanding ASDs.


Assuntos
Hipotálamo/patologia , Vias Neurais/patologia , Receptores de Ocitocina/genética , Transtornos Globais do Desenvolvimento Infantil/genética , Transtornos Globais do Desenvolvimento Infantil/patologia , Feminino , Genótipo , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Caracteres Sexuais , Adulto Jovem
20.
Gene ; 521(2): 265-73, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23545306

RESUMO

NAC transcription factors are plant-specific and play an important role in responses to biotic and abiotic stresses. Populus euphratica is a salt-tolerant tree species growing in semi-arid saline areas. A stress responsive gene was successfully isolated from this species and named PeNAC1. The isolated cDNA encoded a protein containing a conserved NAC domain that belonged to the ATAF subgroup of the NAC protein family. The protein was localized to the nucleus and its C-terminus had transcriptional activation activity. Northern hybridization showed that its expression was strongly induced by drought and salt stress, but only slightly induced by ABA treatment in P. euphratica. Transgenic Arabidopsis overexpressing PeNAC1 showed enhanced tolerance to salt stress, with lower Na(+)/K(+) ratios in the roots and leaves, and significantly inhibited expression levels of AtHKT1. Our results suggest that PeNAC1 plays a role in the plant response to salt stress by regulating Na(+)/K(+) homeostasis.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Populus/genética , Potássio/metabolismo , Tolerância ao Sal/fisiologia , Sódio/metabolismo , Transativadores/fisiologia , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA Complementar/genética , Regulação da Expressão Gênica de Plantas , Homeostase/fisiologia , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Populus/metabolismo , Tolerância ao Sal/genética , Alinhamento de Sequência , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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