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Vacuolar protein sorting 35 (VPS35), a critical component of the retromer complex, plays a pivotal role in the pathogenesis of neurodegenerative diseases (NDs). It is involved in protein transmembrane sorting, facilitating the transport from endosomes to the trans-Golgi network (TGN) and plasma membrane. Recent investigations have compellingly associated mutations in the VPS35 gene with neurodegenerative disorders such as Parkinson's and Alzheimer's disease. These genetic alterations are implicated in protein misfolding, disrupted autophagic processes, mitochondrial dysregulation, and synaptic impairment. Furthermore, VPS35 exerts a notable impact on neurogenesis by influencing neuronal functionality, protein conveyance, and synaptic performance. Dysregulation or mutation of VPS35 may escalate the progression of neurodegenerative conditions, underscoring its pivotal role in safeguarding neuronal integrity. This review comprehensively discusses the role of VPS35 and its functional impairments in NDs. Furthermore, we provide an overview of the impact of VPS35 on neurogenesis and further explore the intricate relationship between neurogenesis and NDs. These research advancements offer novel perspectives and valuable insights for identifying potential therapeutic targets in the treatment of NDs.
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BACKGROUND AND AIMS: The exosomal long noncoding RNAs (lncRNAs) have been reported to have cardioprotective effects on ischemia-reperfusion (I/R) injury by hindering ferroptosis, but the role of lncRNA Mir9-3 host gene (Mir9-3hg) in cardiac I/R injury remains unclear. METHODS AND RESULTS: Exosomes were extracted from mouse bone marrow mesenchymal stem cells (BMSCs) and identified by detecting the exosome specific marker levels, and the results showed that Mir9-3hg was highly expressed in BMSCs-Exo. Hypoxia/reoxygenation (H/R)-treated HL-1 mouse cardiomyocytes were incubated with exosomes extracted from BMSCs transfected with Mir9-3hg siRNA. BMSCs-Exo incubation observably facilitated cell proliferation, increased glutathione (GSH) content, and reduced iron ion concentration, reactive oxygen species (ROS) level and ferroptosis marker protein levels in H/R-treated cells, while interfering Mir9-3hg reversed these effects. RNA binding protein immunoprecipitation assay was found that Mir9-3hg bound with pumilio RNA binding family member 2 (Pum2) protein and downregulated Pum2 expression. Silence of Pum2 reversed the effects of Mir9-3hg inhibition on cell functions. Chromatin immunoprecipitation assay was revealed that Pum2 bound with peroxiredoxin 6 (PRDX6) promoter and restrained PRDX6 expression. Silence of PRDX6 reversed the improved effects of Pum2 downregulation on cell functions. Additionally, BMSCs-Exo treatment ameliorated cardiac function in I/R-treated mice by inhibiting cardiomyocyte ferroptosis. CONCLUSIONS: BMSCs-Exo treatment attenuates I/R-induced cardiac injury by inhibiting cardiomyocyte ferroptosis through modulating the Pum2/PRDX6 axis, thereby ameliorating cardiac function.
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Ferroptose , Miócitos Cardíacos , RNA Longo não Codificante , Traumatismo por Reperfusão , Animais , Células-Tronco Mesenquimais , Camundongos , Miócitos Cardíacos/citologia , Peroxirredoxina VI/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismoRESUMO
Increasing absorbance by lengthening the absorption path is a direct and effective approach to improve the signal-to-noise ratio of infrared gas absorption spectroscopy. However, once the absorption path is extended by designing and optimizing the gas cell structure to a certain extent, a bottleneck will appear due to the difficulties in the optical alignment and the interference effect. A modified tunable diode laser absorption spectroscopy system with a dual fiber loop configuration is proposed that can extend the effective absorption path length of the original multipass cell several times. The relevant theoretical model has been established and its effectiveness has been verified through experiments.
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Mesenchymal stem cells (MSCs) and their secreted exosomes exert a cardioprotective role in jeopardized myocardium. However, the specific effects and underlying mechanisms of exosomes derived from adipose-derived MSCs (ADMSCs) on myocardial ischemia/reperfusion (I/R) injury remain largely unclear. In this study, ADMSC-derived exosomes (ADMSCs-ex) were administrated into the rats subjected to I/R injury and H9c2 cells exposed to hypoxia/reoxygenation (H/R). Consequently, administration of ADMSCs-ex significantly reduced I/R-induced myocardial infarction, accompanied with a decrease in serum levels of creatine kinase-myocardial band, lactate dehydrogenase, and cardiac troponin I (cTnI). Simultaneously, ADMSCs-ex dramatically antagonized I/R-induced myocardial apoptosis, along with the upregulation of Bcl-2 and downregulation of Bax, and inhibition of Caspase 3 activity in rat myocardium. Similarly, ADMSCs-ex significantly reduced cell apoptosis and the expression of Bax, but markedly increased cell viability and the expression of Bcl-2 and Cyclin D1 under H/R. Furthermore, ADMSCs-ex observably induced the activation of Wnt/ß-catenin signaling by attenuating I/R- and H/R-induced inhibition of Wnt3a, p-GSK-3ß (Ser9), and ß-catenin expression. Importantly, treatment with Wnt/ß-catenin inhibitor XAV939 partly neutralized ADMSC-ex-induced antiapoptotic and prosurvival effects in H9c2 cells. In conclusion, we confirmed that ADMSCs-ex protect ischemic myocardium from I/R injury through the activation of Wnt/ß-catenin signaling pathway.
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Tecido Adiposo/transplante , Exossomos/transplante , Células-Tronco Mesenquimais/fisiologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Via de Sinalização Wnt/fisiologia , Animais , Linhagem Celular , Sobrevivência Celular/fisiologia , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/patologia , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Hypoxia is a well-known factor in the promotion of apoptosis, which contributes to the development of numerous cardiac diseases, such as heart failure and myocardial infarction. Inhibiting apoptosis is an important therapeutic strategy for the treatment of related heart diseases caused by ischemia/hypoxic injury. Previous studies have demonstrated that BAG3 plays an important role in cardiomyocyte apoptosis and survival. However, the role of BAG3 in hypoxia-induced cardiomyocyte apoptosis remains to be clarified. Here, we demonstrate that BAG3 is induced by hypoxia stimuli in cultured cardiomyocytes. METHODS: BAG3 expression level was measured in H9c2 cells treated with hypoxia for 48 h. Cell proliferation and apoptosis were tested using MTT assay and Annexin V FITC-PI staining assay, respectively. The mRNA or protein expression level of BAG3, LC3-I, LC3-II, Atg5, NF-x03BA;B p65 and phosphorylated NF-x03BA;B p65 were assessed by qRT-PCR and western blot assay, respectively. Resluts: Overexpression of BAG3 inhibited cell apoptosis and promoted proliferation in hypoxia-injured H9c2 cells. Furthermore, autophagy and NF-x03BA;B were activated by BAG3 overexpression, and the NF-x03BA;B inhibitor PDTC could inhibit the activation of autophagy induced by BAG3 overexpression. In addition, the autophagy inhibitor 3-MA partly impeded the inhibitory effect of BAG3 on hypoxia-induced cardiomyocyte apoptosis. CONCLUSION: these results suggested that overexpression of BAG3 promoted cell proliferation and inhibited apoptosis by activating autophagy though the NF-x03BA;B signaling pathway in hypoxia-injured cardiomyocytes.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Apoptose/genética , Autofagia/genética , Miócitos Cardíacos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Antioxidantes/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Western Blotting , Hipóxia Celular , Linhagem Celular , Sobrevivência Celular/genética , Expressão Gênica , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Miócitos Cardíacos/citologia , Prolina/análogos & derivados , Prolina/farmacologia , Interferência de RNA , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tiocarbamatos/farmacologia , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Regulação para CimaRESUMO
Malignant urban gas accidents, accounting for only approximately 1 % of the total gas accidents in China, are responsible for over 50 % of fatalities, thus becoming a major cause of public concern regarding gas safety. A comprehensive understanding of the characteristics of historical accidents is an effective way to prevent and reduce future accidents. In this regard, the study meticulously collects and analyzes all malignant gas accidents that occurred in China from 2013 to 2022. This approach can effectively clarify the focus of gas accident prevention, and also facilitate the implementation of more targeted preventive measures. The study provides diverse perspectives and comprehensive statistics on accidents using 10 variables in 6 dimensions: time (year, month, day, hour), location (province, place), gas source, type, cause, and level. In addition to common quantitative statistics, proportional analyses and visual displays, methods such as contingency tables, t-tests, chi-square tests, and cluster analyses were also used to provide more in-depth analyses and identify more potential patterns. The findings elucidate that: (1) Over the past decade, the yearly distribution of malignant gas accidents in China has been relatively stable; but, individual, particularly major accidents, have significantly influenced the overall severity; (2) June and July are the peak months for such accidents; (3) The most severe accidents occur during 6:00-6:59 a.m., 11:00-11:59 a.m., and 11:00-11:59 p.m.; (4) Central and eastern provinces are the epicenters of malignant gas accidents; (5) Residential accommodations, and restaurants and shops are frequently affected; (6) Liquefied petroleum gas, despite comprising merely 8.7 % of the aggregate supply, is implicated in over half of the malignant occurrences and associated fatalities; (7) Explosions account for approximately 78.49 % of these accidents; (8) Among the accident causes, violations of rules by workers stands as the foremost contributor; (9) Malignant gas accidents are generally larger accident. Moreover, this manuscript delves into the underlying reasons behind each noteworthy statistical trend and analyzes the critical issues facing the gas industry. This investigation not only bridges the gap in the statistical profiling of malignant gas accidents within China but also furnishes invaluable insights that may guide preventive measures against urban gas-related disasters. Furthermore, the methodological approaches and variable selections explored in this study lay a robust foundation for future endeavors in the realm of malignant gas accident management research and practice.
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OBJECTIVES: To explore the pathogenesis of Alzheimer's disease (AD), the potential targets and signaling pathways of ginsenoside Rg1 against AD were investigated by network pharmacology METHODS: Ginsenoside Rg1 targets were identified through PubChem, PharmMapper, and Uniprot databases, while the GeneCards database was used to examine the respective targets of amyloid precursor protein (APP) and AD. Then, the common targets between ginsenoside Rg1 and APP were explored by the Venny tool, the interaction network diagram between the active components and the targets was built via Cytoscape software, as well as GO enrichment and KEGG pathway annotation analysis were performed. Furthermore, genes associated with ferroptosis were found by the GeneCards and FerrDb databases. Besides, the connection among ginsenoside Rg1, APP, ferroptosis, and AD was predicted and analyzed. Finally, the effects of ginsenosides Rg1 and liproxstain-1 on the proliferation and differentiation of APP/PS1 mice were evaluated by immunohistochemistry RESULTS: Ginsenoside Rg1, APP, ferroptosis, and AD had 12 hub genes. GO enrichment and KEGG pathway annotation analysis showed that EGFR, SRC, protein hydrolysis, protein phosphorylation, the Relaxin pathway, and the FoxO signaling pathway play an important role in the potential mechanism of ginsenoside Rg1's under regulation of ferroptosis anti-AD through the modulation of APP-related signaling pathways. The APP/PS1 mice experiment verified that ginsenosides Rg1 and liproxstain-1 can promote the proliferation and differentiation CONCLUSION: Ginsenoside Rg1, APP and ferroptosis may act on EGFR, SRC, the Relaxin and FoxO signaling pathways to regulate protein metabolism, protein phosphorylation and other pathways to improve AD symptoms.
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The poor survival and differentiation of the donor cells in the infarcted myocardium has hampered the therapeutic efficacy of cell transplantation. A self-assembling polypeptide RAD16-II (Ac-RARADADARARADADA-CONH2) spontaneously assembles into stable nanofiber scaffolds, which mimic natural extracellular matrix at 0.1-1% peptide concentrations in the myocardium. We isolated mesenchymal stem cells from the bone marrow of adult male rats that express both c-kit and Nkx2.5, a cardiac transcription factor, yielding selected mesenchymal stem cells (SMSCs). We initially confirmed that the self-assembling polypeptide scaffolds are conducive to growth, survival and differentiation of SMSCs in vitro. Subsequently, SMSCs mixed with the self-assembling polypeptide were injected into the infarcted area at 30 min after the establishment of myocardial infarction in female rats. The donor cells were tracked with Y chromosome in the myocardium. The changes of cardiac function, myocardial structure and capillary density were detected at 4 weeks after cell transplantation. The hearts transplanted with SMSCs incorporated into the nanofiber scaffolds showed smaller infarction size (19.55 ± 2.1%) than the hearts injected with SMSCs (27.37 ± 4.8%). Importantly, the systolic function indices, left ventricle ejection fraction and left ventricle fractional shortening, were significantly improved in the animals transplanted with SMSCs mixed with the nanofiber scaffolds (59.31 ± 4.9% and 31.91 ± 8.1%), compared to those with SMSCs alone (48.31 ± 9.2% and 23.58 ± 8.5%). In conclusion, transplantation of SMSCs mixed with the self-assembling polypeptide RAD16-II is more effective to promote myocardial regeneration and attenuate cardiac injury in a rat model of myocardial infarction.
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Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Infarto do Miocárdio/terapia , Peptídeos/uso terapêutico , Sequência de Aminoácidos , Animais , Apoptose/efeitos dos fármacos , Capilares/efeitos dos fármacos , Capilares/patologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Testes de Função Cardíaca/efeitos dos fármacos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Dados de Sequência Molecular , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Nanofibras/ultraestrutura , Peptídeos/química , Peptídeos/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
Myocardial infarction (MI) causes myocardium injury and scar formation, and the transmural infarction is associated with ventricular hypofunction. Stem cell transplantation therapy has improved cardiac function in animal models of MI. However, the poor survival of the donor cells in the host myocardium hampers the therapeutic efficacy of stem cell transplantation. Diazoxide, a mitochondrial ATP-sensitive potassium channel opener, has been applied to suppress cell apoptosis and promote cell survival. We therefore assessed the effects of diazoxide on the selected mesenchymal stem cells (SMSCs). Pretreatment of SMSCs with diazoxide (200 micromol/L) for 30 min protected cells from oxidative stress injury by upregulating the expression of basic fibroblast growth factor and hepatocyte growth factor mRNAs and phospho-Akt and by preventing mitochondral cytochrome c translocation into the cytoplasm. Expression of mRNAs and proteins was detected by RT-PCR and western blot analyses. Thirty min after establishment of MI (the ligation of the left anterior descending of coronary artery) in female rats, the male rat SMSCs preconditioned with diazoxide were injected at four sites on the edge of the infarcted area. At 4 weeks after cell tranplantation, the donor cells in the recipient myocardium were tracked with Y chromosome. Preconditioning with diazoxide improved the survival rate of the transplanted SMSCs, compared to the untreated SMSCs. Moreover, transplantation of the diazoxide-pretreated SMSCs reduced the infarct size and increased left ventricular function, as judged by transthoracic echocardiography. In conclusion, diazoxide preconditioning is effective to promote SMSCs survival under oxidative stress and attenuates cardiac injury in MI.
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Citoproteção/efeitos dos fármacos , Diazóxido/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/efeitos dos fármacos , Infarto do Miocárdio/terapia , Canais de Potássio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Colágeno/metabolismo , Citocromos c/metabolismo , Ácidos Decanoicos/farmacologia , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Fator de Crescimento de Hepatócito/genética , Peróxido de Hidrogênio/farmacologia , Hidroxiácidos/farmacologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Desenvolvimento Muscular/fisiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Miocárdio/patologia , Neovascularização Fisiológica/fisiologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Troponina T/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Função Ventricular Esquerda/fisiologiaRESUMO
Reactive oxygen species (ROS)-triggered cardiac cell injury is recognized as the major contributor for the pathogenesis progression of ischaemic cardiovascular diseases. Sulfiredoxin-1 (Srx-1) is an endogenous antioxidant and exerts the crucial neuroprotective effects in cerebral ischaemia. However, its function and the underlying mechanism in ischaemic heart diseases remain poorly defined. Here, a dramatical decrease in Srx-1 was validated in H9c2 cardiomyocytes upon simulated ischaemia-reperfusion (SI/R) injury. Moreover, Srx-1 protected H9c2 cells from SI/R-injured injury as the evidences that Srx-1 up-regulation attenuated the inhibitory effects on cell viability, lactate dehydrogenase (LDH) and cell apoptosis upon SI/R treatment. Knockdown of Srx-1 accelerated cell injury upon SI/R. Mechanism assay corroborated that SI/R treatment noticeably aggravated the loss of mitochondrial membrane potential (Δψm), which was remarkably abated in Ad-Srx-1 groups. Importantly, Srx-1 elevation substantially reduced cytochrome c release, the activity of caspase-9 and caspase-3, accompany with the subsequent decrease in the cleavage of poly (ADP ribose) polymerase (PARP). Concomitantly, overexpression of Srx-1 also decreased the expression of pro-apoptosis protein Bax and increased anti-apoptotic Bcl-2 expression. Further analysis substantiated that Srx-1 treatment remarkably induced the activation of PI3K/AKT signalling. Preconditioning with LY294002 dramatically decreased Srx-1-enhanced cell resistance to SI/R injury. Importantly, LY294002 mitigated the inhibitory effects of Srx-1 on Δψm loss, cytochrome c release, caspase-9/3 activity, and the expression of Bcl-2 family. Together, these results suggested that Srx-1 might protect cardiomyocyte injury upon SI/R by suppressing PI3K/AKT-mediated mitochondria dependent apoptosis, revealing a promising therapeutic agent against ischaemic cardiovascular diseases.
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Apoptose , Mitocôndrias Cardíacas/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Linhagem Celular , Mitocôndrias Cardíacas/genética , Mitocôndrias Cardíacas/patologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , RatosRESUMO
Photodynamic therapy (PDT) with protoporphyrin IX (PpIX), which is endogenously derived from 5-aminolevulinic acid (5-ALA) or its derivatives, is a promising modality for the treatment of both pre-malignant and malignant lesions. However, the mechanisms of how ALA-induced PpIX selectively accumulated in the tumors are not fully elucidated. Here we discovered that eukaryotic translation elongation factor 1 alpha 1 (eEF1A1) interacted with PpIX (with an affinity constant of 2.96 × 10(6) M(-1)). Microscopy imaging showed that ALA-induced PpIX was co-localized with eEF1A1 in cancer cells. eEF1A1 was found to enrich ALA-induced PpIX in cells by competitively blocking the downstream bioavailability of PpIX. Taken together, our study discovered eEF1A1 as a novel photosensitizer binding protein, which may play an essential role in the enrichment of ALA-induced PpIX in cancer cells during PDT. These suggested eEF1A1 as a molecular marker to predict the selectivity and efficiency of 5-ALA based PDT in cancer therapy.
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Neoplasias/metabolismo , Fator 1 de Elongação de Peptídeos/genética , Fotoquimioterapia/métodos , Protoporfirinas/metabolismo , Ácido Aminolevulínico/farmacocinética , Ácido Aminolevulínico/farmacologia , Disponibilidade Biológica , Linhagem Celular , Biblioteca Gênica , Células Hep G2 , Humanos , Neoplasias/tratamento farmacológico , Fator 1 de Elongação de Peptídeos/metabolismo , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/farmacologia , Ligação ProteicaRESUMO
In order to examine how implanted bone marrow stromal cells (BMSCs) encourage peripheral nerve regeneration, the present study investigated the interaction of BMSCs and Schwann cells (SCs) using an indirect in vitro coculture model. SCs and BMSCs were obtained from adult SpragueDawley rats. The passaged BMSCs were CD29 and CD44positive but CD45negative and were cocultured with the primary SCs using a Millicell system, which allows BMSCs and SCs to grow in the same culture medium but without direct contact. Expression of the typical SC markers S100 and glial fibrillary acidic protein (GFAP) of the treated BMSCs as well as the proliferation capacity of the cocultured SCs was evaluated by immunocytochemical staining on the 3rd and 5th day of coculture. Immunocytochemical staining showed that >75% of the BMSCs in the indirect coculture model were GFAP and S100positive on the 3rd and 5th day after coculture, as opposed to <5% of the BMSCs in the control group. On the 3rd day after coculture, only a few cocultured BMSCs showed the typical SClike morphology, while most BMSCs still kept their native appearance. By contrast, on the 5th day after coculture, almost all of the cocultured BMSCs appeared with the typical SClike morphology. Furthermore, 70.71% of the SCs in the indirect coculture model were S100positive on the 5th day of coculture, as opposed to >30.43% of the SCs in the control group. These results indicated that BMSCs may interact synergistically with SCs with regard to promoting peripheral nerve regeneration.
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Técnicas de Cocultura/métodos , Células-Tronco Mesenquimais/citologia , Células de Schwann/citologia , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Regulação da Expressão Gênica , Marcadores Genéticos , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Regeneração Nervosa , Nervos Periféricos/citologia , Ratos , Ratos Sprague-Dawley , Proteínas S100/genética , Proteínas S100/metabolismoRESUMO
Airway remodeling can lead to irreversible airflow obstruction and persistent airway hyper-responsiveness, which is the pathological basis of refractory asthma. To investigate the preventive effect of protocatechuic aldehyde on airway remodeling in asthmatic mice by lung morphometry methods. BALB/c mice were used to establish model of airway remodeling by ovalbumin (OVA) inhalation. Bronchoalveolar lavage fluid (BALF) were collected for eosinophils (EOS) count and detection of interleukin 4 (IL-4), interleukin-13 (IL-13) and interferon (IFN-γ) content. The left lung pathological sections were performed HE, AB-PAS and Masson staining. The epithelial lamina thickness of the left main bronchus (Re), the smooth muscle layer thickness (Rm), the number of goblet cells and goblet cell area percentage (%Ac) and gas side of the road and vascular collagen deposition (%Aco, %Avc) situation were measured. Protocatechuic aldehyde gavage made the reduction of BALF EOS count. IL-4 and IL-13 levels also decreased, while the IFN-γ level increased. The left main bronchus Re, Rm, goblet cell count, Ac% and Aco% and Avc% reduced. Protocatechuic aldehyde can significantly control airway inflammation and prevent airway remodeling.
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Fine iron oxide particles (IOPs) are effective in removing natural organic matter (NOM) that causes membrane fouling in water treatment, but the separation of used IOPs is problematic. This study focused on the fabrication and use of granular iron oxide adsorbents, in combination with ultrafiltration (UF) membranes while investigating the NOM removal efficiency and fouling control. Sulfonated styrene-divinylbenzene copolymer beads were coated with two types of iron oxides (ferrihydrite and magnetite) and their performances were compared to that of fine IOPs. A significant amount of iron oxide coating (52-63 mg of Fe per g bead) was achieved by means of electrostatic binding and hydrolysis of iron ions. Iron oxide coated polymer (IOCP) beads were able to remove some amounts (≈ 20%) of dissolved organic carbon (DOC) comparable to that achieved by IOPs within a short period of time (<15 min). Regenerated IOCPs exhibited the same sorption capacity as the fresh ones. The integrated IOCP/UF system operation with a 15-min empty bed contact time and 10-h cyclic regeneration maintained the 20% DOC removal with no sign of significant membrane fouling. In contrast, a sharp transmembrane pressure buildup occurred in the UF system when no iron oxide pretreatment was applied, regardless of the types of membranes tested. Iron oxide adsorbed the NOM fraction with molecular weights of >1000 kDa which is believed to be responsible for severe UF fouling.
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Incrustação Biológica/prevenção & controle , Compostos Férricos/química , Substâncias Húmicas/análise , Ultrafiltração , Purificação da Água , Adsorção , Carbono/análise , Cromatografia em Gel , Membranas Artificiais , Microscopia Eletrônica de Varredura , Microesferas , Polímeros/química , Pressão , Fatores de TempoRESUMO
A simple and sensitive kinetic-spectrophotometric method was developed for the determination of ultra trace amount of formaldehyde in food samples. The method was based on the oxidation of rhodamine B (RhB) by potassium bromate in sulfuric acid medium (formaldehyde as catalyst). The reaction was monitored by measuring the decrease in absorbance of the dye at 515 nm after 6 min. The developed method allowed the determination of formaldehyde in the range of 10-100 microg L(-1) with good precision, accuracy and the detection limit was down to 2.90 microg L(-1). The relative standard deviations for the determination of 10 and 60 microg L(-1) of formaldehyde were 3.0% and 1.9% (n = 10), respectively. The method was found to be sensitive, selective and was applied to the determination of formaldehyde in foods with satisfactory results.