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1.
Int J Mol Sci ; 23(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408924

RESUMO

Tapetal programmed cell death (PCD) is a complex biological process that plays an important role in pollen formation and reproduction. Here, we identified the MYB2 transcription factor expressed in the tapetum from stage 5 to stage 11 that was essential for tapetal PCD and pollen development in Arabidopsis thaliana. Downregulation of MYB2 retarded tapetal degeneration, produced defective pollen, and decreased pollen vitality. EMSA and transcriptional activation analysis revealed that MYB2 acted as an upstream activator and directly regulated expression of the proteases CEP1 and ßVPE. The expression of these proteases was lower in the buds of the myb2 mutant. Overexpression of either/both CEP1 or/and ßVPE proteases partially recover pollen vitality in the myb2 background. Taken together, our results revealed that MYB2 regulates tapetal PCD and pollen development by directly activating expression of the proteases CEP1 and ßVPE. Thus, a transcription factor/proteases regulatory and activated cascade was established for tapetal PCD during another development in Arabidopsis thaliana. Highlight: MYB2 is involved in tapetal PCD and pollen development by directly regulating expression of the protease CEP1 and ßVPE and establishes a transcription factor/proteases regulatory and activated cascade.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fenômenos Biológicos , Apoptose , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Pólen , Transativadores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Mol Pharm ; 16(5): 2184-2198, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30925218

RESUMO

In this study, the time-dependent evolution of amorphous probucol nanoparticles was characterized by cryogenic transmission electron microscopy (cryo-TEM) and atomic force microscopy (AFM). The nanoparticles were formed by dispersing ternary solid dispersions of probucol in water. Spray drying and cogrinding were used to prepare a spray-dried sample (SPD) and two ground-mixture samples (GM(I) and GM(II)) of probucol (PBC) form I and form II/hypromellose/sodium dodecyl sulfate ternary solid dispersions. The amorphization of PBC in the SPDs and GMs was confirmed using powder X-ray diffraction (PXRD) and solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Additionally, differential scanning calorimetry showed that relatively small amounts of PBC nuclei or PBC-rich domains remained in both GMs. Then, the physical stability of drug nanoparticles formed after aqueous dispersion in the SPD and GM suspensions during storage at 40 °C was characterized. Cryogenic transmission electron microscopy was used to monitor the evolution of the amorphous PBC nanoparticles in the SPD and GM suspensions during storage. Spherical nanoparticles smaller than 30 nm were observed in all of the suspensions just after dispersion. The size of the particles in the SPD suspension gradually increased but remained on the order of nanometers and retained their spherical shape during storage. In contrast, both GM suspensions evolved through three morphologies, spherical nanoparticles that gradually increased in size, needle-like nanocrystals, and micrometer-sized crystals with various shapes. The evolution of the nanoparticles suggested that their stability in the GM suspension was lower than in the SPD suspension. PXRD analysis of the freeze-dried suspensions of the particles showed that the PBC in the nanoparticles of the SPD suspension was in the amorphous state just after dispersion, while a small fraction of the PBC in the nanoparticles of the GM suspension exhibited a crystal phase and selectively crystallized to its initial crystal form during storage. AFM force-distance curves also demonstrated the existence of crystal phase PBC in the spherical nanoparticles in the GM suspension just after dispersion. The molecular state of PBC in the ternary solid dispersion was dependent on the preparation method (either completely amorphized or incompletely amorphized with residual nuclei or drug-rich domains) and determined the potential mechanisms of PBC nanoparticle evolution after aqueous dispersion. These findings confirm the importance of the molecular state on the particle evolution and the physical stability of the drug nanoparticles in the suspension. Cryo-TEM and AFM measurements provide more direct insight for designing solid dispersion formulations to produce stable amorphous drug nanosuspensions that efficiently improve the solubility and bioavailability of poorly water-soluble drugs.


Assuntos
Desenho de Fármacos , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Transmissão/métodos , Nanopartículas/química , Probucol/química , Água/química , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Cristalização , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Liofilização , Espectroscopia de Ressonância Magnética , Tamanho da Partícula , Solubilidade , Suspensões , Difração de Raios X
3.
J Cell Mol Med ; 22(10): 5132-5144, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30063115

RESUMO

Mitophagy eliminates dysfunctional mitochondria and thus plays a cardinal role in diabetic cardiomyopathy (DCM). We observed the favourable effects of melatonin on cardiomyocyte mitophagy in mice with DCM and elucidated their underlying mechanisms. Electron microscopy and flow cytometric analysis revealed that melatonin reduced the number of impaired mitochondria in the diabetic heart. Other than decreasing mitochondrial biogenesis, melatonin increased the clearance of dysfunctional mitochondria in mice with DCM. Melatonin increased LC3 II expression as well as the colocalization of mitochondria and lysosomes in HG-treated cardiomyocytes and the number of typical autophagosomes engulfing mitochondria in the DCM heart. These results indicated that melatonin promoted mitophagy. When probing the mechanism, increased Parkin translocation to the mitochondria may be responsible for the up-regulated mitophagy exerted by melatonin. Parkin knockout counteracted the beneficial effects of melatonin on the cardiac mitochondrial morphology and bioenergetic disorders, thus abolishing the substantial effects of melatonin on cardiac remodelling with DCM. Furthermore, melatonin inhibited Mammalian sterile 20-like kinase 1 (Mst1) phosphorylation, thus enhancing Parkin-mediated mitophagy, which contributed to mitochondrial quality control. In summary, this study confirms that melatonin rescues the impaired mitophagy activity of DCM. The underlying mechanism may be attributed to activation of Parkin translocation via inhibition of Mst1.


Assuntos
Cardiomiopatias Diabéticas/tratamento farmacológico , Fator de Crescimento de Hepatócito/genética , Melatonina/administração & dosagem , Proteínas Proto-Oncogênicas/genética , Ubiquitina-Proteína Ligases/genética , Animais , Apoptose/efeitos dos fármacos , Autofagossomos/efeitos dos fármacos , Autofagossomos/patologia , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/patologia , Modelos Animais de Doenças , Fator de Crescimento de Hepatócito/antagonistas & inibidores , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/genética , Camundongos , Mitocôndrias/genética , Mitocôndrias/patologia , Mitofagia/genética , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Fosforilação/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/genética , Proteínas Proto-Oncogênicas/antagonistas & inibidores
4.
Biochem Biophys Res Commun ; 495(1): 292-299, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29127009

RESUMO

BACKGROUND: Cardiomyocyte autophagy and apoptosis are crucial events underlying the development of cardiac abnormalities and dysfunction after myocardial infarction (MI). A better understanding of the cell signaling pathways involved in cardiac remodeling may support the development of new therapeutic strategies for the treatment of heart failure (HF) after MI. METHODS: A cardiac MI injury model was constructed by ligating the left anterior descending (LAD) coronary artery. Neonatal cardiomyocytes were isolated and cultured to investigate the mechanisms underlying the protective effects of nicorandil on MI-induced injury. RESULTS: Nicorandil reduced cardiac enzyme release, mitigated left ventricular enlargement and cardiac dysfunction after MI, as evaluated by echocardiography and hemodynamic measurements. According to the results of the western blot analysis and immunofluorescence staining, nicorandil enhanced autophagic flux and reduced apoptosis in cardiomyocytes subjected to hypoxic injury. Interestingly, nicorandil increased Mst1 and p-Mst1 levels in cardiomyocytes subjected to MI injury. Mst1 knockout abolished the protective effects of nicorandil on cardiac remodeling and dysfunction after MI. Mst1 knockout also abolished the beneficial effects of nicorandil on cardiac enzyme release and cardiomyocyte autophagy and apoptosis. CONCLUSIONS: Nicorandil alleviates post-MI cardiac dysfunction and remodeling. The mechanisms were associated with enhancing autophagy and inhibiting apoptosis through Mst1 inhibition.


Assuntos
Fator de Crescimento de Hepatócito/antagonistas & inibidores , Fator de Crescimento de Hepatócito/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/fisiopatologia , Nicorandil/administração & dosagem , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Disfunção Ventricular Esquerda/tratamento farmacológico , Disfunção Ventricular Esquerda/fisiopatologia , Animais , Cardiotônicos/administração & dosagem , Relação Dose-Resposta a Droga , Fator de Crescimento de Hepatócito/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/complicações , Proteínas Proto-Oncogênicas/genética , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia , Remodelação Ventricular/efeitos dos fármacos
5.
Med Sci Monit ; 24: 6851-6860, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30260937

RESUMO

BACKGROUND α1-antitrypsin (α1-AT) is highly expressed in many tumors. However, to the best of our knowledge, its relationship to triple negative breast cancer (TNBC) has not yet been studied. Thus, in this research we first explored the influence of α1-AT silencing on the abilities of migration and invasion, and then further study its molecular mechanism in TNBC cells. MATERIAL AND METHODS The viability of MDA-MB-231 cells were detected using cell counting kit-8 (CCK-8). The abilities of migration and invasion were examined by Transwell assay. The metastasis-related factors were tested respectively by quantitative real-time PCR (qRT-PCR) and western blot assays. RESULTS Our study results showed that α1-AT level in TNBC tissues was higher than non-triple negative breast cancer (n-TNBC) and adjacent normal breast tissues. The high expression of α1-AT was linked to type of cancer, tumor size, TNM stage and metastasis, but was not correlated with α1-AT expression and age. si-α1-AT suppressed the viability, migration, and invasion of cells. While si-α1-AT upregulated E-cadherin and the tissue inhibitor of metalloproteinases-2 (TIMP-2) levels, it downregulated metastasis associated 1 (MTA1), matrix metallopeptidase 2 (MMP2), phosphorylated-mammalian target of rapamycin (p-mTOR), phosphorylated-protein kinase B (p-Akt), and phosphorylated-phosphatidylinositol 3 kinase (p-PI3K) levels. We also found that the PI3K/Akt/mTOR pathway activator reversed the role of si-α1-AT in metastasis-related factors. CONCLUSIONS α1-AT was highly expressed in TNBC tissues, and its silencing suppressed the abilities of migration and invasion in TNBC cells and downregulated the PI3K/Akt/mTOR pathway. Thus, α1-AT may have a potential therapeutic effect on TNBC.


Assuntos
Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , alfa 1-Antitripsina/metabolismo , Adulto , Idoso , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Fosforilação , Transdução de Sinais , Transcriptoma , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , alfa 1-Antitripsina/genética
6.
Biochim Biophys Acta Mol Basis Dis ; 1863(8): 1962-1972, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27613967

RESUMO

Myocardial infarction (MI), which is characterized by chamber dilation and left ventricular (LV) dysfunction, represents a major cause of morbidity and mortality worldwide. Polydatin (PD), a monocrystalline and polyphenolic drug isolated from a traditional Chinese herb (Polygonum cuspidatum), alleviates mitochondrial dysfunction. We investigated the effects and underlying mechanisms of PD in post-MI cardiac dysfunction. We constructed an MI model by left anterior descending (LAD) coronary artery ligation using wild-type (WT) and Sirt3 knockout (Sirt3-/-) mice. Cardiac function, cardiomyocytes autophagy levels, apoptosis and mitochondria biogenesis in mice that underwent cardiac MI injury were compared between groups. PD significantly improved cardiac function, increased autophagy levels and decreased cardiomyocytes apoptosis after MI. Furthermore, PD improved mitochondrial biogenesis, which is evidenced by increased ATP content, citrate synthase (CS) activity and complexes I/II/III/IV/V activities in the cardiomyocytes subjected to MI injury. Interestingly, Sirt3 knockout abolished the protective effects of PD administration. PD inhibited apoptosis in cultured neonatal mouse ventricular myocytes subjected to hypoxia for 6h to simulate MI injury. PD increased GFP-LC3 puncta, and reduced the accumulation of protein aggresomes and p62 in cardiomyocytes after hypoxia. Interestingly, the knock-down of Sirt3 nullified the PD-induced beneficial effects. Thus, the protective effects of PD are associated with the up-regulation of autophagy and improvement of mitochondrial biogenesis through Sirt3 activity.


Assuntos
Apoptose , Glucosídeos/farmacologia , Mitocôndrias Cardíacas/metabolismo , Infarto do Miocárdio/prevenção & controle , Miócitos Cardíacos/metabolismo , Biogênese de Organelas , Sirtuína 3/metabolismo , Estilbenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Mitocôndrias Cardíacas/genética , Mitocôndrias Cardíacas/patologia , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Sirtuína 3/genética
7.
Biochim Biophys Acta Mol Basis Dis ; 1863(8): 1951-1961, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27825852

RESUMO

The incidence and prevalence of heart failure (HF) in the world are rapidly rising possibly attributed to the worsened HF following myocardial infarction (MI) in recent years. Here we examined the effects of oncostatin M (OSM) on postinfarction cardiac remodeling and the underlying mechanisms involved. MI model was induced using left anterior descending coronary artery (LAD) ligation. In addition, cultured neonatal mouse cardiomyocytes were subjected to simulated MI. Our results revealed that OSM alleviated left ventricular remodeling, promoted cardiac function, restored mitochondrial cristae density and architecture disorders after 4weeks of MI. Enhanced autophagic flux was indicated in cardiomyocytes transduced with Ad-GFP -LC3 in the OSM treated group as compared with the MI group. OSM receptor Oß knockout blocked the beneficial effects of OSM in postinfarction cardiac remodeling and cardiomyocytes autophagy. OSM pretreatment significantly alleviated left ventricular remodeling and dysfunction in Mst1 transgenic mice, while it failed to reverse further the postinfarction left ventricular dilatation and cardiac function in the Mst1 knockout mice. Our data revealed that OSM alleviated postinfarction cardiac remodeling and dysfunction by enhancing cardiomyocyte autophagy. OSM holds promise as a therapeutic target in treating HF after MI through Oß receptor by inhibiting Mst1 phosphorylation.


Assuntos
Autofagia , Fator de Crescimento de Hepatócito/metabolismo , Infarto do Miocárdio/metabolismo , Oncostatina M/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Disfunção Ventricular Esquerda/metabolismo , Remodelação Ventricular , Animais , Fator de Crescimento de Hepatócito/genética , Camundongos , Camundongos Knockout , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Oncostatina M/genética , Subunidade beta de Receptor de Oncostatina M/genética , Subunidade beta de Receptor de Oncostatina M/metabolismo , Proteínas Proto-Oncogênicas/genética , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/patologia
8.
Lancet ; 386(10002): 1457-64, 2015 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-26142048

RESUMO

BACKGROUND: Helicobacter pylori is one of the most common gastric pathogens, affecting at least half the world's population, and is strongly associated with gastritis, peptic ulcer, gastric adenocarcinoma, and lymphoma. We aimed to assess the efficacy, safety, and immunogenicity of a three-dose oral recombinant H pylori vaccine in children in China. METHODS: We did this randomised, double-blind, placebo-controlled, phase 3 trial at one centre in Ganyu County, Jiangsu Province, China. Healthy children aged 6-15 years without past or present H pylori infection were randomly assigned (1:1), via computer-generated randomisation codes in blocks of ten, to receive the H pylori vaccine or placebo. Participants, their guardians, and study investigators were masked to treatment allocation. The primary efficacy endpoint was the occurrence of H pylori infection within 1 year after vaccination. We did analysis in the per-protocol population. This trial is registered with ClinicalTrials.gov, number NCT02302170. FINDINGS: Between Dec 2, 2004, and March 19, 2005, we randomly assigned 4464 participants to either the vaccine group (n=2232) or the placebo group (n=2232), of whom 4403 (99%) participants completed the three-dose vaccination schedule and were included in the per-protocol efficacy analysis. We extended follow-up to 3 years. We recorded 64 events of H pylori infection within the first year (14 events in 2074·3 person-years at risk in the vaccine group vs 50 events in 2089·6 person-years at risk in the placebo group), resulting in a vaccine efficacy of 71·8% (95% CI 48·2-85·6). 157 (7%) participants in the vaccine group and 161 (7%) participants in the placebo group reported at least one adverse reaction. Serious adverse events were reported in five (<1%) participants in the vaccine group and seven (<1%) participants in the placebo group, but none was considered to be vaccination related. INTERPRETATION: The oral recombinant H pylori vaccine was effective, safe, and immunogenic in H pylori-naive children. This vaccine could substantially reduce the incidence of H pylori infection; however, follow up over a longer period is needed to confirm the protection of the vaccine against H pylori-associated diseases. FUNDING: Chongqing Kangwei Biological Technology.


Assuntos
Vacinas Bacterianas/administração & dosagem , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/imunologia , Administração Oral , Adolescente , Fatores Etários , Vacinas Bacterianas/efeitos adversos , Vacinas Bacterianas/imunologia , Criança , Método Duplo-Cego , Feminino , Infecções por Helicobacter/imunologia , Humanos , Imunidade Ativa/imunologia , Masculino , Proteínas Recombinantes , Fatores Sexuais , Resultado do Tratamento
9.
Apoptosis ; 20(9): 1150-63, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26093524

RESUMO

Oncostatin M (OSM) exhibits many unique biological activities by activating the Oß receptor. However, its role in myocardial ischemia/reperfusion injury (I/R injury) in mice remains unknown. We investigated whether Notch3/Akt signaling is involved in the regulation of OSM-induced protection against cardiac I/R injury. The effects of OSM were assessed in mice that underwent myocardial I/R injury by OSM treatment or by genetic deficiency of the OSM receptor Oß. We investigated its effects on cardiomyocyte apoptosis and mitochondrial biogenesis and whether Notch3/Akt signaling was involved in the regulation of OSM-induced protection against cardiac I/R injury. The mice underwent 30 min of ischemia followed by 3 h of reperfusion and were randomized to be treated with Notch3 siRNA (siNotch3) or lentivirus carrying Notch3 cDNA (Notch3) 72 h before coronary artery ligation. Myocardial infarct size, cardiac function, cardiomyocyte apoptosis and mitochondria morphology in mice that underwent cardiac I/R injury were compared between groups. OSM alleviated cardiac I/R injury by inhibiting cardiomyocyte apoptosis through promotion of Notch3 production, thus activating the PI3K/Akt pathway. OSM enhanced mitochondrial biogenesis and mitochondrial function in mice subjected to cardiac I/R injury. In contrast, OSM receptor Oß knock out exacerbated cardiac I/R injury, decreased Notch3 production, enhanced cardiomyocyte apoptosis, and impaired mitochondrial biogenesis in cardiac I/R injured mice. The mechanism of OSM on cardiac I/R injury is partly mediated by the Notch3/Akt pathway. These results suggest a novel role of Notch3/Akt signaling that contributes to OSM-induced protection against cardiac I/R injury.


Assuntos
Inibidores do Crescimento/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Oncostatina M/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos , RNA Interferente Pequeno/metabolismo , Ratos , Receptor Notch3 , Receptores de Oncostatina M/genética , Receptores de Oncostatina M/metabolismo
10.
Int J Pharm ; 640: 122959, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37086931

RESUMO

In our previous reports, ternary amorphous solid dispersions (ASDs) of probucol (PBC)/polymer/surfactant were prepared by spray-drying and cryo-grinding, and colloidal dispersions of amorphous PBC nanoparticles were obtained by dispersing the ternary ASD into water. In this study, hot-melt extrusion, which is a practical method for preparing ASD formulations, was utilized to obtain ternary ASDs and colloidal dispersions of amorphous PBC nanoparticles. Polyvinylpyrrolidone K12 (PVP) with a relatively low Tg (below 100 °C) was used as a polymer, while poloxamer P407 (P407), which is chemically stable during the hot-melt extrusion process, was utilized as a surfactant. Ternary ASDs were successfully produced with high weight ratios of PVP and P407. A hydrogen bond between the PBC hydroxyl proton and PVP carbonyl oxygen in the ternary ASD was detected using solid-state NMR spectroscopy, suggesting that amorphous PBC was stabilized mainly by PVP. Stable colloidal dispersions of amorphous PBC nanoparticles were obtained from the PBC/PVP/P407 ASD at a weight ratio of 1:4:2. The mean particle size was below 200 nm and the amorphous state of PBC remained stable upon storage at 25 °C for 14 d. Solution-state 1H NMR and zeta-potential measurements suggested that P407 mainly stabilized the colloidal dispersion of amorphous PBC nanoparticles by steric hindrance at the solid/liquid interface. The findings of this study demonstrate that hot-melt extrusion can form practical ternary ASDs that provide colloidal dispersion of amorphous drug nanoparticles. Thus, this study advocates for the use of hot-melt extrusion in the design of an amorphous formulation for a variety of poorly water-soluble drugs.


Assuntos
Nanopartículas , Probucol , Composição de Medicamentos/métodos , Solubilidade , Polímeros/química , Povidona/química , Tensoativos/química , Água/química
11.
Toxics ; 11(5)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37235225

RESUMO

Disinfection by-products (DBPs) are the most common organic contaminants in tap water and are of wide concern because of their highly developmental toxic, cytotoxic, and carcinogenic properties. Typically, to control the proliferation of pathogenic microorganisms, a certain concentration of residual chlorine is retained in the factory water, which reacts with the natural organic matter and the disinfection by-products that have been formed, thus affecting the determination of DBPs. Therefore, to obtain an accurate concentration, residual chlorine in tap water needs to be quenched prior to treatment. Currently, the most commonly used quenching agents are ascorbic acid, sodium thiosulfate, ammonium chloride, sodium sulfite, and sodium arsenite, but these quenching agents can cause varying degrees of DBPs degradation. Therefore, in recent years, researchers have attempted to find emerging chlorine quenchers. However, no studies have been conducted to systematically review the effects of traditional quenchers and new ones on DBPs, as well as their advantages, disadvantages, and scope of application. For inorganic DBPs (bromate, chlorate, and chlorite), sodium sulfite has been proven to be the ideal chlorine quencher. For organic DBPs, although ascorbic acid caused the degradation of some DBPs, it remains the ideal quenching agent for most known DBPs. Among the studied emerging chlorine quenchers, n-acetylcysteine (NAC), glutathione (GSH), and 1,3,5-trimethoxybenzene are promising for their application as the ideal chlorine quencher of organic DBPs. The dehalogenation of trichloronitromethane, trichloroacetonitrile, trichloroacetamide, and bromochlorophenol by sodium sulfite is caused by nucleophilic substitution reaction. This paper takes the understanding of DBPs and traditional and emerging chlorine quenchers as a starting point to comprehensively summarize their effects on different types of DBPs, and to provide assistance in understanding and selecting the most suitable residual chlorine quenchers during DBPs research.

12.
Math Biosci Eng ; 19(1): 707-737, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34903009

RESUMO

Singular point detection is a primary step in fingerprint recognition, especially for fingerprint alignment and classification. But in present there are still some problems and challenges such as more false-positive singular points or inaccurate reference point localization. This paper proposes an accurate core point localization method based on spatial domain features of fingerprint images from a completely different viewpoint to improve the fingerprint core point displacement problem of singular point detection. The method first defines new fingerprint features, called furcation and confluence, to represent specific ridge/valley distribution in a core point area, and uses them to extract the innermost Curve of ridges. The summit of this Curve is regarded as the localization result. Furthermore, an approach for removing false Furcation and Confluence based on their correlations is developed to enhance the method robustness. Experimental results show that the proposed method achieves satisfactory core localization accuracy in a large number of samples.


Assuntos
Dermatoglifia
13.
Exp Ther Med ; 24(3): 598, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35949337

RESUMO

The onset and progression of non-alcoholic fatty liver disease (NAFLD) remains unclear, but short-chain fatty acids (SCFAs) in circulation may participate in its pathogenesis by acting as inflammation inhibitors. The aim of this retrospective study was to investigate plasma concentrations of general SCFAs in healthy individuals and in patients with distinct stages of NAFLD. Three main SCFAs (including acetate, propionate and butyrate) were analyzed by gas chromatography. The plasma TNF-α concentration was measured by ELISA. One-way ANOVA, Spearman's correlation and Pearson's correlation analysis were performed to estimate the associations between SCFAs, TNF-α and disease progression. Multiple linear stepwise regression was computed to explore the predictor variables of TNF-α in circulation. A total of 71 patients with NAFLD [including 27 patients with NAFL, 20 patients with non-alcoholic steatohepatitis (NASH) and 24 patients with NAFLD-related cirrhosis (NAFLD-cirrhosis)] and 9 healthy control (HC) subjects were enrolled for analysis. Although not statistically significant, plasma SCFAs were elevated in patients with NAFL compared with HC subjects, whereas the vast majority of SCFAs were statistically reduced in patients with NASH or NAFLD-cirrhosis compared with patients with NAFL. Plasma SCFAs had no significant differences in NASH or NAFLD-cirrhosis patients compared with HC subjects. In addition, significant negative correlations were observed between TNF-α and SCFAs. The progression of NAFLD (ß=0.849; P<0.001) and the decline of the total three SCFA concentrations (ß=-0.189; P<0.001) were recognized as independent risk variables related to the elevated peripheral TNF-α in the multiple linear stepwise regression model. Plasma SCFA concentrations may alter with the development of NAFLD and may have a potential link to TNF-α and the progression of NAFLD, which may serve a protective role toward disease advancement. Further mechanistic studies, such as analysis of gastrointestinal microecology, signaling pathways and functions involved in TNF-α, need to be performed. Also, therapeutic supplementation of SCFAs for NASH and NAFLD-cirrhosis needs further research and verification.

14.
Oxid Med Cell Longev ; 2022: 3858500, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36124086

RESUMO

Background: Berberine (BER) is a natural isoquinoline alkaloid which extensively been applied to treat bacterial infection in TCM for a long time. Alginate is an important component of Pseudomonas aeruginosa biofilm. Herein, we investigated the effects of berberine and azithromycin (AZM) on alginate in the biofilm of P. aeruginosa PAO1. Methods: The MIC and synergistic activity of BER and AZM against PAO1 were determined using the micro broth dilution and checkerboard titration methods, respectively. The effect of BER on PAO1 growth was evaluated using a time-kill assay. Moreover, the effects of BER, AZM, and a combination of both on PAO1 biofilm formation, kinesis, and virulence factor expression were evaluated at subinhibitory concentrations. The alginate content in the biofilm was detected using ELISA, and the relative expression of alginate formation-related genes algD, algR, and algG was detected by qRT-PCR. Results: Simultaneous administration of berberine significantly reduced the MIC of azithromycin, and berberine at a certain concentration inhibited PAO1 growth. Moreover, combined berberine and azithromycin had synergistic effects against PAO1, significantly reducing biofilm formation, swarming, and twitching motility, and the production of virulence factors. The relative expression of alginate-related regulatory genes algG, algD, and algR of the combined treatment group was significantly lower than that of the control group. Conclusion: In summary, berberine and azithromycin in combination had a significant synergistic effect on the inhibition of alginate production by P. aeruginosa. Further molecular studies are in great need to reveal the mechanisms underlying the synergistic activity between berberine and azithromycin.


Assuntos
Berberina , Pseudomonas aeruginosa , Alginatos/metabolismo , Azitromicina/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Berberina/farmacologia , Isoquinolinas/farmacologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Fatores de Virulência/farmacologia
15.
Gastroenterol Res Pract ; 2022: 9556161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126511

RESUMO

BACKGROUND AND AIMS: Ulcerative colitis (UC) is associated with an increased risk of colorectal cancer. Current guidelines recommend endoscopic resection if the lesion is visible with distinct margins and a complete resection can be achieved. However, submucosal fibrosis due to chronic inflammation may increase the procedural risk and reduce the complete resection rate. The aim of this study is to assess the efficacy and safety of endoscopic submucosal dissection (ESD) for dysplasia in UC patients. MATERIALS AND METHODS: A systematic search of databases was performed until May 30, 2021. Studies that reported the resection rates and complication rates of ESD for dysplasia in UC patients were included. A random-effects model was used to generate conservative estimates of the prevalence of the outcome variables. All data analyses were performed using software Stata (version 15). RESULTS: 8 studies were enrolled in the meta-analysis, with a total of 203 dysplastic lesions in 192 UC patients. The mean lesion size was 26.7 mm. About 83% of the lesions were located in the left-side colon, and 90% of the lesions were nonpolypoid, and about 71% of the lesions had submucosal fibrosis. The mean procedural time of ESD was 83 minutes. The en bloc resection rate, complete resection rate, and curative resection rate were 94%, 84%, and 81%, respectively, with a local recurrence rate of 5%. The pooled prevalence of bleeding and perforation were 8% and 6%, respectively. The rates of metachronous tumors and additional surgery after ESD were 6% and 10%, respectively. CONCLUSION: Despite some limitations, our study suggests that ESD is an effective and safe treatment for dysplasia in UC patients. However, randomized controlled multicenter studies with less heterogeneity and longer follow-up are needed to better assess the clinical outcomes of ESD in UC patients.

16.
Biochim Biophys Acta Mol Basis Dis ; 1868(12): 166533, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36064133

RESUMO

Phagocytosis of oxidized low-density lipoprotein (OxLDL) by macrophages yields "foam cells" and serves as a hallmark of atherosclerotic lesion. Adipsin is a critical component of the complement activation pathway. Recent evidence has indicated an obligatory role for Adipsin in pathological models including ischemia-reperfusion and sepsis. Adipsin levels are significantly decreased in patients with asymptomatic carotid atherosclerosis, implying the role for Adipsin as a potential marker of asymptomatic carotid atherosclerosis. This study was designed to evaluate the role for Adipsin in atherosclerosis and the mechanisms involved using both in vivo and in vitro experiments. ApoE-/-/AdipsinTg mice were constructed and were fed a high-fat diet for 12 weeks. Compared with ApoE-/- mice, area of the sclerotic plaques was reduced, along with lower macrophage deposition within the plaque in ApoE-/-/AdipsinTg mice. RAW264.7 cells and bone marrow-derived macrophages (BMDMs) were stimulated with oxLDL (50 µg/ml). Adenovirus vectors containing the Adipsin gene were transfected into macrophages. Lipid accumulation was observed by Oil red O staining. Western blot and reverse transcription-polymerase chain reaction data revealed that Adipsin overexpression inhibited oxLDL-induced lipid uptake and foam cell formation and upregulation of CD36 and PPARγ in Ad-Adipsin-transfected macrophages. In addition, the PPARγ-specific agonist GW1929 reversed Adipsin overexpression-evoked inhibitory effect on lipid uptake. These results demonstrate unequivocally that Adipsin inhibits lipid uptake in a PPARγ/CD36-dependent manner and prevents the formation of foam cells, implying that Adipsin may be a potential therapeutic target against atherosclerosis.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Placa Aterosclerótica , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/metabolismo , Antígenos CD36/metabolismo , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/patologia , Fator D do Complemento/genética , Fator D do Complemento/metabolismo , Células Espumosas , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Camundongos , PPAR gama/metabolismo , Placa Aterosclerótica/metabolismo , Transdução de Sinais
17.
Front Cardiovasc Med ; 9: 895167, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722108

RESUMO

Background: The healing response of the Firehawk stent in patients with ST-segment elevation myocardial infarction (STEMI) remains unclear. Aim: We compared the vascular healing of a biodegradable polymer sirolimus-eluting stent (Firehawk) vs. a durable polymer everolimus-eluting stent (Xience) at 6 months after percutaneous coronary intervention (PCI) in patients with STEMI. Methods: In this prospective, multicenter, randomized, non-inferiority study, patients within 12 h of STEMI onset were randomized in a ratio of 1:1 to receive Firehawk or Xience stents. Optical coherence tomography (OCT) follow-up was performed 6 months after the index procedure and assessed frame by frame. The primary endpoint was the neointimal thickness (NIT) at 6 months evaluated by OCT. The safety endpoint was target lesion failure (TLF) at 12 months. Results: The Firehawk stent was non-inferior to the Xience stent in terms of the neointimal thickness (73.03 ± 33.30 µm vs. 78.96 ± 33.29 µm; absolute difference: -5.94 [one-sided 95% lower confidence bound: -23.09]; P non-inferiority < 0.001). No significant difference was observed between the Firehawk and Xience groups regarding the percentage of uncovered struts (0.55 [0.08, 1.32]% vs. 0.40 [0.21, 1.19]%, P = 0.804), the percentage of malapposed struts (0.17 [0.00, 1.52]% vs. 0.17 [0.00, 0.69]%, P = 0.662), and the healing score (1.56 [0.23, 5.74] vs. 2.12 [0.91, 3.81], P = 0.647). At 12 months, one patient in the Firehawk group experienced a clinically indicated target lesion revascularization. No other TLF events occurred in both groups. Independent risk factors of the NIT included body mass index, hyperlipidemia, B2/C lesions, thrombus G3-G5, thrombus aspiration, and postdilation pressure. Conclusion: In patients with STEMI, Firehawk was non-inferior to Xience in vascular healing at 6 months. Both stents exhibited nearly complete strut coverage, moderate neointimal formation, and minimal strut malapposition. Clinical Trial Number: NCT04150016.

18.
Int J Pharm ; 607: 120984, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34389423

RESUMO

Probucol (PBC)/hypromellose (HPMC)/sodium dodecyl sulfate (SDS) ternary solid dispersions (SDs) of various weight ratios were prepared and evaluated to unveil the effect of HPMC and SDS on the formation of amorphous PBC nanoparticles. The morphological variation of the PBC nanoparticles prepared using SDs of different compositions was determined using dynamic light scattering and cryogenic transmission electron microscopy (cryo-TEM). Statistical analysis of particle size versus roundness of PBC nanoparticles was carried out based on cryo-TEM images. A clear correlation was observed between the morphologies of the PBC nanoparticles and the amounts of HPMC and SDS, either admixed in SDs or pre-dissolved in an aqueous solution. The admixed HPMC in SDs was demonstrated to play the major role in determining the primary particle sizes of discrete amorphous PBC nanoparticles. Based on 13C solid-state NMR spectroscopy, this phenomenon should be due to the enlarged size of the PBC-rich domains in SDs, which depended on the decreasing amounts of admixed HPMC. Although the pre-dissolved part of HPMC had less impact on the primary particle sizes, it was found to inhibit the particle agglomeration and recrystallization of amorphous PBC nanoparticles. On the other hand, sufficient SDS admixed in SDs could suppress the size enhancement of the PBC-rich domains during water immersion and nanoparticle evolution (agglomeration and crystallization) after aqueous dispersion. The pre-dissolved SDS could restrain the agglomeration of amorphous PBC nanoparticles, ultimately forming hundreds of irregular nanometer-order structures. Since the increase in size during water immersion, their sizes were still slightly larger than those obtained with a high portion of admixed SDS. The findings of this study clarified the usefulness and necessity of adding polymers and surfactants to SDs to fabricate drug nanoparticle formulations.


Assuntos
Nanopartículas , Preparações Farmacêuticas , Derivados da Hipromelose , Tamanho da Partícula , Solubilidade , Água
19.
Int J Pharm ; 581: 119300, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32268185

RESUMO

The potential for inhibiting recrystallization with Eudragit® L (EUD-L), hypromellose acetate succinate (HPMC-AS), and polyvinylpyrrolidone-co-vinylacetate (PVP-VA) on amorphous felodipine (FLD) at low polymer loading was investigated in this study. The physical stabilities of the FLD/polymer amorphous solid dispersions (ASDs) were investigated through storage at 40 °C. The HPMC-AS and PVP-VA strongly inhibited FLD recrystallization, although EUD-L did not effectively inhibit the FLD recrystallization. The rotating frame 1H spin-lattice relaxation time (1H-T1ρ) measurement clarified that EUD-L was not well mixed with FLD in the ASD, which resulted in weak inhibition of recrystallization by EUD-L. In contrast, the HPMC-AS and PVP-VA were well mixed with the FLD in the ASDs. Solid-state 13C spin-lattice relaxation time (13C-T1) measurements at 40 °C showed that the molecular mobility of the FLD was strongly suppressed when mixed with polymer. The reduction in the molecular mobility of FLD was in the following order, starting with the least impact: FLD/EUD-L ASD, FLD/HPMC-AS ASD, and FLD/PVP-VA ASD. FLD mobility at the storage temperature, evaluated by 13C-T1, showed a good correlation with the physical stability of the amorphous FLD. The direct investigation of the molecular mobility of amorphous drugs at the storage temperature by solid-state NMR relaxation time measurement can be a useful tool in selecting the most effective crystallization inhibitor at low polymer loading.


Assuntos
Isótopos de Carbono/química , Química Farmacêutica/métodos , Força Compressiva , Cristalização/métodos , Felodipino/química , Polímeros/química , Antiarrítmicos/análise , Antiarrítmicos/química , Isótopos de Carbono/análise , Portadores de Fármacos/análise , Portadores de Fármacos/química , Felodipino/análise , Previsões , Polímeros/análise
20.
J Ovarian Res ; 13(1): 145, 2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33308258

RESUMO

BACKGROUND: GAS5 contains a hormone response element that can induce cell apoptosis in breast cancer. It is known that cell apoptosis and hormone response play crucial roles in polycystic ovary syndrome (PCOS), indicating the potential involvement of GAS5 in PCOS. This study was performed to investigate the potential involvement of GAS5 and IL-6 (a critical player in PCOS) in PCOS. METHODS: Research subjects of this study included 60 PCOS patients and 60 healthy controls. The expression levels of GAS5 and IL-6 in plasma of both patients and controls were measured by qPCR and ELISA, respectively. Cell transfections were performed to analyze the interaction between GAS5 and IL-6. Cell apoptosis was analyzed by cell apoptosis assay. RESULTS: GAS5 was upregulated in plasma of PCOS patients. The expression levels of GAS5 were positively correlated with the expression levels of IL-6. Altered expression levels of GAS5 and IL-6 distinguished PCOS patients from healthy controls. In cells of a granulosa-like tumor cell line (KGN), overexpression of GAS5 led to upregulated IL-6, while silencing of GAS5 played an opposite role. Cell apoptosis analysis showed that overexpression of GAS5 significantly decreased apoptosis rate of KGN cells. Silencing of GAS5 increased the rate of KGN cell apoptosis. CONCLUSIONS: GAS5 is upregulated in PCOS and regulates cell apoptosis and the expression of IL-6.


Assuntos
Interleucina-6/biossíntese , Síndrome do Ovário Policístico/sangue , RNA Longo não Codificante/sangue , Adulto , Apoptose/fisiologia , Estudos de Casos e Controles , Feminino , Humanos , Interleucina-6/sangue , Interleucina-6/genética , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/patologia , RNA Longo não Codificante/genética , Transfecção , Regulação para Cima , Adulto Jovem
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