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1.
Malar J ; 23(1): 48, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360586

RESUMO

BACKGROUND: Immunogenic cell death (ICD) is a type of regulated cell death that plays a crucial role in activating the immune system in response to various stressors, including cancer cells and pathogens. However, the involvement of ICD in the human immune response against malaria remains to be defined. METHODS: In this study, data from Plasmodium falciparum infection cohorts, derived from cross-sectional studies, were analysed to identify ICD subtypes and their correlation with parasitaemia and immune responses. Using consensus clustering, ICD subtypes were identified, and their association with the immune landscape was assessed by employing ssGSEA. Differentially expressed genes (DEGs) analysis, functional enrichment, protein-protein interaction networks, and machine learning (least absolute shrinkage and selection operator (LASSO) regression and random forest) were used to identify ICD-associated hub genes linked with high parasitaemia. A nomogram visualizing these genes' correlation with parasitaemia levels was developed, and its performance was evaluated using receiver operating characteristic (ROC) curves. RESULTS: In the P. falciparum infection cohort, two ICD-associated subtypes were identified, with subtype 1 showing better adaptive immune responses and lower parasitaemia compared to subtype 2. DEGs analysis revealed upregulation of proliferative signalling pathways, T-cell receptor signalling pathways and T-cell activation and differentiation in subtype 1, while subtype 2 exhibited elevated cytokine signalling and inflammatory responses. PPI network construction and machine learning identified CD3E and FCGR1A as candidate hub genes. A constructed nomogram integrating these genes demonstrated significant classification performance of high parasitaemia, which was evidenced by AUC values ranging from 0.695 to 0.737 in the training set and 0.911 to 0.933 and 0.759 to 0.849 in two validation sets, respectively. Additionally, significant correlations between the expressions of these genes and the clinical manifestation of P. falciparum infection were observed. CONCLUSION: This study reveals the existence of two ICD subtypes in the human immune response against P. falciparum infection. Two ICD-associated candidate hub genes were identified, and a nomogram was constructed for the classification of high parasitaemia. This study can deepen the understanding of the human immune response to P. falciparum infection and provide new targets for the prevention and control of malaria.


Assuntos
Morte Celular Imunogênica , Malária Falciparum , Humanos , Relevância Clínica , Plasmodium falciparum/genética , Estudos Transversais , Malária Falciparum/genética , Biologia Computacional , Aprendizado de Máquina
2.
Glia ; 70(12): 2392-2408, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35946355

RESUMO

Growing evidence indicates that circulating lactoferrin (Lf) is implicated in peripheral cholesterol metabolism disorders. It has emerged that the distribution of Lf changes in astrocytes of aging brains and those exhibiting neurodegeneration; however, its physiological and/or pathological role remains unknown. Here, we demonstrate that astrocyte-specific knockout of Lf (designated cKO) led to decreased body weight and cognitive abnormalities during early life in mice. Accordingly, there was a reduction in neuronal outgrowth and synaptic structure in cKO mice. Importantly, Lf deficiency in the primary astrocytes led to decreased sterol regulatory element binding protein 2 (Srebp2) activation and cholesterol production, and cholesterol content in cKO mice and/or in astrocytes was restored by exogenous Lf or a Srebp2 agonist. Moreover, neuronal dendritic complexity and total dendritic length were decreased after culture with the culture medium of the primary astrocytes derived from cKO mice and that this decrease was reversed after cholesterol supplementation. Alternatively, these alterations were associated with an activation of AMP-activated protein kinase (AMPK) and inhibition of SREBP2 nuclear translocation. These data suggest that astrocytic Lf might directly or indirectly control in situ cholesterol synthesis, which may be implicated in neurodevelopment and several neurological diseases.


Assuntos
Astrócitos , Proteína de Ligação a Elemento Regulador de Esterol 2 , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Astrócitos/metabolismo , Colesterol/metabolismo , Lactoferrina/genética , Lactoferrina/metabolismo , Lactoferrina/farmacologia , Camundongos , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
3.
Malar J ; 21(1): 333, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36380373

RESUMO

BACKGROUND: To understand how Plasmodium falciparum malaria is controlled, it is essential to elucidate the transcriptomic responses of the human host in naturally-exposed populations. Various individual studies of the human transcriptomic responses to naturally transmitted P. falciparum infections have been reported with varying results. Multicohort gene expression analysis by aggregating data from diverse populations into a single analysis will increase the reproducibility and reliability of the results. METHODS: In this study, discovery cohorts GSE1124-GPL96, GSE34404, GSE117613, and validation cohort GSE35858 were obtained from the Gene Expression Omnibus. A meta-analysis using data from the multicohort studies was performed to identify the differentially expressed genes (DEGs) between malaria-infected and noninfected individuals using the MetaIntegrator R package. Subsequently, the protein-protein interaction (PPI) networks of the DEGs were constructed using Cytoscape software. Significant modules were selected, and the hub genes were identified using the CytoHubba and MCODE plug-ins. Multicohort WGCNA was conducted to find a correlation between modules and malaria infection. Furthermore, the immune cell profile of the peripheral blood in different groups was identified using ssGSEA. RESULTS: These analyses reveal that neutrophil activation, neutrophil-mediated immunity, and neutrophil degranulation are involved in the human response to natural malaria infection. However, neutrophil cell enrichment and activation were not significantly different between mild malaria and severe malaria groups. Malaria infection also downregulates host genes in ribosome synthesis and protein translation and upregulates host cell division-related genes. Furthermore, immune cell profiling analysis shows that activated dendritic cells and type 2 T helper cells are upregulated, while activated B cells, immature B cells, and monocytes are downregulated in the malaria-infected patients relative to the noninfected individuals. Significantly higher enrichment of activated dendritic cell-related genes and significantly lower enrichment of monocyte-related genes are also observed in the peripheral blood of the severe malaria group than in the mild malaria group. CONCLUSION: These results reveal important molecular signatures of host responses to malaria infections, providing some bases for developing malaria control strategies and protective vaccines.


Assuntos
Malária Falciparum , Malária , Humanos , Plasmodium falciparum/genética , Reprodutibilidade dos Testes , Perfilação da Expressão Gênica , Transcriptoma
4.
Circulation ; 139(23): 2668-2684, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832495

RESUMO

BACKGROUND: The adult mammalian cardiomyocytes lose their proliferative capacity, which is responsible for cardiac dysfunction and heart failure following injury. The molecular mechanisms underlying the attenuation of adult cardiomyocyte proliferation remain largely unknown. Because long noncoding RNAs (lncRNAs) have a critical role in the development of cardiovascular problems, we investigated whether lncRNAs have any role in the regulation of cardiomyocyte proliferation and cardiac repair. METHODS: Using bioinformatics and initial analysis, we identified an lncRNA, named CPR (cardiomyocyte proliferation regulator), that has a potential regulatory role in cardiomyocyte proliferation. For in vivo experiments, we generated CPR knockout and cardiac-specific CPR-overexpressing mice. In isolated cardiomyocytes, we used adenovirus for silencing (CPR-small interfering RNA) or overexpressing CPR. To investigate the mechanisms of CPR function in cardiomyocyte proliferation, we performed various analyses including quantitative reverse transcription-polymerase chain reaction, Western blot, histology, cardiac function (by echocardiography), transcriptome analyses (microarray assay), RNA pull-down assay, and chromatin immunoprecipitation assay. RESULTS: CPR level is comparatively higher in the adult heart than in the fetal stage. The silencing of CPR significantly increased cardiomyocyte proliferation in postnatal and adult hearts. Moreover, CPR deletion restored the heart function after myocardial injury, which was evident from increased cardiomyocyte proliferation, improvement of myocardial function, and reduced scar formation. In contrast, the neonatal cardiomyocyte proliferation and cardiac regeneration were remarkably suppressed in CPR-overexpressing mice or adeno-associated virus serotype 9-CPR-overexpressing heart. These results indicate that CPR acts as a negative regulator of cardiomyocyte proliferation and regeneration. Next, we found that CPR targets minichromosome maintenance 3, an initiator of DNA replication and cell cycle progression, to suppress cardiomyocyte proliferation. CPR silenced minichromosome maintenance 3 expression through directly interacting and recruiting DNMT3A to its promoter cysteine-phosphate-guanine sites, as evident from decreased minichromosome maintenance 3 promoter methylation and increased minichromosome maintenance 3 expression in CPR knocked-down cardiomyocytes and CPR knockout mouse heart. These results were confirmed in CPR-overexpressing cardiomyocytes and CPR-overexpressing mouse heart. CONCLUSIONS: Together, our findings identified that CPR is a suppressor of cardiomyocyte proliferation and indicated that lncRNAs take part in the regulation of cardiomyocyte proliferation and cardiac repair. Our study provides an lncRNA-based therapeutic strategy for effective cardiac repair and regeneration.


Assuntos
Proliferação de Células , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/metabolismo , Regeneração , Animais , Animais Recém-Nascidos , Sítios de Ligação , Ciclo Celular , Células Cultivadas , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Modelos Animais de Doenças , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Componente 3 do Complexo de Manutenção de Minicromossomo/genética , Componente 3 do Complexo de Manutenção de Minicromossomo/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , Transdução de Sinais
5.
Anal Chem ; 91(16): 10864-10869, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31359752

RESUMO

Here, we fabricated a novel photoelectrochemical (PEC) aptasensor based on Br,N-codoped TiO2/CdS quantum dots (QDs) sensitization structure with excellent energy level arrangement for supersensitive detection of carcinoembryonic antigen (CEA). The prepared Br,N-codoped TiO2 could reduce the energy bandwidth of TiO2 from 3.2 to 2.88 eV, which could dramatically reduce the basic signal and obviously broaden the absorption of light (400-700 nm). In addition, the energy bandwidth of Br,N-codoped TiO2 (2.88 eV) matched well with that of CdS QDs (2.4 eV), making CdS QDs an ideal signal enhancer for amplifying the photocurrent signal of Br,N-codoped TiO2. More importantly, the constructed Br,N-codoped TiO2/CdS QDs sensitization structure with narrow energy level gradient enabled the effective promotion of electron-transfer capability and dramatic improvement of photoelectric conversion efficiency. Simultaneously, a small amount of the CEA was transformed into substantial single-chain DNA (T-DNA) via exonuclease III (Exo-III)-assisted cycle strategy. Under optimum conditions, the designed PEC aptasensor demonstrated a wide detection range from 1 fg/mL to 1 ng/mL and a low detection limit as 0.46 fg/mL for CEA assay. This strategy prepared a new photoactive material to markedly improve photoelectric conversion efficiency and initiated a new way to realize the highly sensitive PEC biomolecules detection.

6.
Cell Mol Neurobiol ; 39(1): 111-122, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30511325

RESUMO

Epilepsy is a commonly occurring neurological disease that has a large impact on the patient's daily life. Phosphorylation of heat shock protein B6 (HspB6) has been reported to protect the central nervous system. In this investigation, we explored whether HspB6 played a positive effect on epilepsy with the involvement of the cyclic adenosine monophosphate-protein kinase A (cAMP-PKA) pathway. The epileptic seizure was induced in rats by intraperitoneal injection of kainic acid (KA). The extent of HspB6 phosphorylation and expressions of HspB6, PKA, and inflammatory factors TNF-α, IL-1ß, and IL-6 were quantified along with neuronal apoptosis. To further understand the regulatory mechanism of the HspB6 in the hippocampus, we altered the expression and the extent of HspB6 phosphorylation to see whether the cAMP-PKA pathway was inactivated or not in hippocampal neurons of rats post KA. Results showed that HspB6 was poorly expressed, resulting in the inactivation of the cAMP-PKA pathway in rats post KA, as well as an aggravated inflammatory response and hippocampal neuronal apoptosis. HspB6 overexpression and the cAMP-PKA pathway activation decreased the expression of inflammatory factors and inhibited hippocampal neuronal apoptosis. Additionally, HspB6 phosphorylation further augments the inhibitory effects of HspB6 on the inflammatory response and hippocampal neuronal apoptosis. The cAMP-PKA pathway activation was found to result in increased HspB6 phosphorylation. HspB6 decreased apoptosis signal-regulating kinase 1 (ASK1) expression to inhibit inflammatory response and hippocampal neuronal apoptosis. Collectively, our findings demonstrate that activation of the cAMP-PKA pathway induces overexpression and partial phosphorylation of HspB6 lead to the inhibition of ASK1 expression. This in turn protects rats against epilepsy and provides a potential approach to prevent the onset of epileptic seizure in a clinical setting.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Proteínas de Choque Térmico HSP20/metabolismo , Convulsões/metabolismo , Convulsões/patologia , Transdução de Sinais , Animais , Apoptose , Sequência de Bases , Regulação para Baixo , Hipocampo/patologia , Inflamação/metabolismo , Inflamação/patologia , Ácido Caínico , MAP Quinase Quinase Quinase 5/metabolismo , Masculino , Neurônios/metabolismo , Neurônios/patologia , Fosforilação , Ratos Sprague-Dawley
7.
J Gastroenterol Hepatol ; 34(12): 2152-2157, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31318990

RESUMO

BACKGROUND AND AIM: An endoscopic clip device was newly designed to accomplish the closure of large gastrointestinal defects. The aim of this study was to determine the feasibility and efficacy of this device in an ex vivo experimental setting. METHODS: This prospective study was conducted in porcine colons (n = 5). A large (3-4 cm) linear full-thickness incision was created using a scalpel externally. The device was used for endoscopic closure. The procedure time, number of clips, and success rate of closure were determined. RESULTS: Ten defects were created in five porcine colons (two incisions in each specimen). Successful closure was achieved in all defects. The mean procedure time was 24.30 ± 4.42 min, the mean leak pressure is 28.30 ± 9.49 mmHg, and the mean number of additional conventional hemostatic clips used was 5.10 ± 0.99. CONCLUSIONS: The results indicated that this clip achieved the convenient and reliable closure of large defects in the colon wall in an ex vivo porcine model and seems to be a promising option for closing large gastrointestinal perforations.


Assuntos
Técnicas de Fechamento de Ferimentos Abdominais/instrumentação , Colo/cirurgia , Colonoscopia/instrumentação , Perfuração Intestinal/cirurgia , Instrumentos Cirúrgicos , Animais , Colonoscopia/métodos , Modelos Animais de Doenças , Desenho de Equipamento , Estudos de Viabilidade , Estudos Prospectivos , Sus scrofa
8.
Anal Chem ; 90(20): 12278-12283, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30227710

RESUMO

Here, a photoelectrochemical (PEC) biosensor was established by a cosensitization strategy with cascade energy level arrangement for ultrasensitive detection of prostate-specific antigen (PSA). The proposed cosensitization strategy was based on the well-matched energy level arrangement of four kinds of organic photoactive materials, in which poly{4,8-bis[5-(2-ethylhexyl)thiophen-2-yl]benzo[1,2- b:4,5- b']dithiophene-2,6-diyl- alt-3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4- b]thiophene-4,6-diyl} (PTB7-Th) was used as the photoactive material and perylenetetracarboxyl diimide (PDI), fullerene (nano-C60), and polyaniline (PANI) were employed as the sensitizers. The resulting PTB7-Th/PDI/nano-C60/PANI cascade cosensitization structure with narrow energy level gradient (<0.54 eV) could effectively improve electron transfer capability, obviously raise light energy utilization and significantly enhance photoelectric conversion efficiency, leading to dramatically enhanced photocurrent response. Using PSA as a target model, the proposed PEC biosensor exhibited high sensitivity and excellent stability with a wide detection range from 1 fg/mL to 0.1 ng/mL and a detection limit of 0.43 fg/mL. Moreover, the proposed PEC biosensor provides a cascade cosensitization strategy that could significantly improve PEC performances and open up a promising platform to establish high selectivity, stability, and ultrasensitive analytical techniques.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Antígeno Prostático Específico/análise , Compostos de Anilina/química , Fulerenos/química , Humanos , Estrutura Molecular , Processos Fotoquímicos , Polímeros/química , Tiofenos/química
9.
Surg Endosc ; 30(11): 5108-5116, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27005294

RESUMO

BACKGROUND AND AIMS: Sedation with propofol alone during gastroscopy has many side effects. Etomidate has advantages in terms of circulation and respiration compared to propofol. We hypothesized that etomidate plus propofol during gastroscopy would be more safe and effective than propofol alone. METHODS: Four hundred (n = 400) patients were randomly divided into a propofol group (P group) and a etomidate plus propofol group (EP group). The P group was given the first dose of 1 % propofol 1 mg/kg before gastroscopy, and the EP group was given 1 % propofol 0.5 mg/kg plus etomidate 0.1 mg/kg. Repeated doses of 10-20 mg propofol or 5-10 mg propofol plus 1-2 mg etomidate were administered to maintain an adequate level of sedation. The sedation depth was maintained by bispectral index value of 40-60. RESULTS: The EP group had a lower incidence of systolic hypotension (13.0 vs. 32.5 %; P < 0.0001), bradycardia (8.5 vs. 16.5 %; P = 0.0226), mild hypoxemia (6.5 vs. 18.0 %; P = 0.0007), and severe hypoxemia (2.5 vs. 10.0 %; P = 0.0031) compared to the P group. Also, the satisfaction of anesthetist and gastroscopist with EP was higher than that of P group (P < 0.0001; P = 0.018, respectively). CONCLUSION: Etomidate plus propofol had few effects on respiration and circulation in patients undergoing gastroscopy and was more safe and effective than propofol alone.


Assuntos
Anestésicos Intravenosos/uso terapêutico , Etomidato/uso terapêutico , Gastroscopia , Propofol/uso terapêutico , Adulto , Atitude do Pessoal de Saúde , Bradicardia/induzido quimicamente , Quimioterapia Combinada , Feminino , Humanos , Hipotensão/induzido quimicamente , Hipóxia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego , Adulto Jovem
10.
World J Diabetes ; 15(7): 1509-1517, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39099812

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) combined with serum endothelin and galactagoglobin-3 (Gal-3) can improve the clinical diagnosis of diabetes mellitus complicated with cerebral infarction. AIM: To analyze the clinical value of MRI combined with serum endolipin and Gal-3 for the diagnosis of cerebral infarction in the elderly with diabetes mellitus. METHODS: One hundred and fifty patients with acute cerebral infarction hospitalized between January 2021 and December 2023 were divided into two groups according to comorbid diabetes mellitus, including 62 and 88 cases in the diabetic and nondiabetic cerebral infarction groups. Serum samples were collected to detect the expression of serum endolipoxins, and Gal-3, and cranial MRI was performed at admission. Differences between the two groups were compared to analyze the diagnostic value of these parameters. RESULTS: Serum endolipin and Gal-3 expression were higher in the diabetic cerebral infarction group (P < 0.05). The arterial wall area, vessel area, normalized wall index, and lumen stenosis rate were higher in the diabetic cerebral infarction group, while the rate of arterial lumen moderate and severe stenosis was 48.39% higher (36.36%, P < 0.05). The percentage of large (29.03%) and multiple infarcts (33.87%) in the diabetic cerebral infarction group was higher (13.64% and 20.45%), and the incidence rate of lacunar infarcts was lower (37.10% vs 65.91%) (P < 0.05). The total incidence of arterial plaque in patients in the diabetic cerebral infarction group was 96.77% higher (69.32%), while the incidence of necrotic lipid core plaque was 58.06% higher (26.14%) (P < 0.05). Receiver operating characteristic curve analysis was performed to assess the diagnosis utility of these techniques. MRI in combination with serum endoglin and Gal-3 had the highest area under the curve, the Yoden index, sensitivity and specificity (P < 0.05). CONCLUSION: The expression of serum endolipin and Gal-3 in elderly patients with diabetes mellitus with cerebral infarction showed an elevated trend, and the degree of luminal stenosis was severe. MRI predominantly revealed large and multiple infarct foci. This combined index examination can improve the clinical diagnosis of diabetes mellitus combined with cerebral infarction.

11.
Phytomedicine ; 135: 156091, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39332101

RESUMO

BACKGROUND: ß-Amyloid (Aß) fibrillation is critical for Aß deposition and cytotoxicity during the progression of Alzheimer's disease (AD). Consequently, anti-Aß monoclonal antibody drugs targeting Aß oligomers and aggregation are considered potential therapeutic strategies for AD treatment. Similar to the working mechanisms of anti-Aß monoclonal antibody drugs, our study identified osmundacetone (OAC), a small-molecule compound isolated from the traditional Chinese medicine Rhizoma Osmundae, as exerting anti-AD effects by targeting Aß. PURPOSE: This study sought to determine whether OAC influences the Aß burden in APP/PS1 mice and to identify potential regulatory mechanisms. METHODS: Five-month-old APP/PS1 mice were injected intraperitoneally with OAC at a dose of 1 mg/kg for 12 weeks. The cognitive functions of the mice were assessed via the Morris water maze test and the open field test. Osmundacetone was analyzed via molecular docking, an isothermal dose‒response fingerprint-cellular context thermal shift assay, a thioflavine T fluorescence assay, and an atomic force microscopy assay to analyze the effects of OAC on Aß fibrillation. Immunofluorescence, immunoblotting, and immunohistochemistry were used to assess Aß clearance, AD pathology, oxidative stress, and inflammatory responses. RESULTS: The innovative biochemical and physical data illustrated that the ability of OAC to inhibit Aß fibrillation was accomplished by binding directly to Aß, which differed from the majority of previously reported natural polyphenols that modulate the Aß content and structure in an indirect manner. The inhibition of Aß fibrosis by OAC subsequently promoted Aß lysosomal degradation, resulting in a decreased Aß burden in APP/PS1 mice. Furthermore, OAC treatment inhibited oxidative damage by upregulating glutathione peroxidase expression and attenuated the production of inflammatory factors by downregulating nuclear factor-kB phosphorylation in APP/PS1 mice. CONCLUSION: These findings demonstrate, for the first time, that OAC could reduce the brain Aß burden in APP/PS1 mice by inhibiting Aß fibrillation through direct binding to Aß and improve cognitive dysfunction by attenuating oxidative damage and neuroinflammation. These findings indicate that OAC may be a promising candidate for the treatment of AD.

12.
Huan Jing Ke Xue ; 45(6): 3584-3594, 2024 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-38897778

RESUMO

In order to investigate the effects of ammonium sulfate, an industrial by-product, on soil nutrients and microbial community when applied in different proportions instead of using urea as nitrogen fertilizer, a pot corn experiment was conducted. A completely randomized block experimental design was used, with a total of five treatments:CK (no fertilization), U10S0 (100 % urea), U8S2 (80 % urea + 20 % ammonium sulfate), U6S4(60 % urea + 40 % ammonium sulfate), and U0S10 (100 % ammonium sulfate). The basic physical and chemical properties of soil and the dry weight of maize plants were determined by conventional methods, and microbial sequencing was performed using the Illumina NovaSeq platform. The experiment results showed that:① In each growth stage of maize, the pH of soil treated with fertilization (7.85-8.15) was decreased compared with that of CK (8.1-8.21), and the pH showed a decreasing trend with the increase in ammonium sulfate content. ② The soil available nitrogen content increased gradually with the increase in the ammonium sulfate ratio at each growth stage of maize. Compared with that in the CK and U10S0 treatments, the ratio in the U0S10 treatment increased 30.56 % to 63.68 % and 13.22 % to 38.43 %, respectively. The variation trend of organic carbon content was opposite to that of available nitrogen (U8S2 > U6S4 > U0S10), and the addition of ammonium sulfate was still higher than that of U10S0 at other growth stages except for the seedling stage. ③ The protease activity of all fertilization treatments was higher than that of the control, and the protease activity was gradually enhanced with the continuous growth of corn and the increase in the ammonium sulfate ratio. The protease activity of the U0S10 treatment was higher than that of the U10S0 treatment at each growth stage of corn, which increased by 10.54 %-100 %. Soil sucrase activity ranged from 0.04 to 0.24 mg·(g·24 h)-1, and those in the U0S10 treatments were significantly higher than those in the U10S0 and CK treatments at all growth stages, increasing by 20.32 % to 99.16 % and 24.31 % to 79.33 %, respectively. ④ The species abundance of bacteria and fungi in maize rhizosphere under all fertilization treatments were lower than those under the CK treatment, followed by those under the U10S0 treatment. The species diversity trend of the bacterial community in the three treatments with ammonium sulfate replacing urea were U8S2 > U0S10 > U6S4, and that of fungi were U6S4 > U8S2 > U0S10. ⑤ The maize dry weight of the U10S0 treatment and U0S10 treatment was the highest, which was 39.47 % and 36.16 % higher than that of the CK treatment, respectively, but the difference was not significant. The Pearson model showed that the species abundance and diversity of soil rhizosphere fungi and bacteria were affected by relevant environmental variables, among which pH value and soil available nitrogen content were the most important factors affecting microbial diversity. In conclusion, when corn planting in calcareous brown soil, replacing urea with a certain proportion of ammonium sulfate can improve soil nutrients more than urea alone, which affects the growth and rhizosphere microbial community of corn to a certain extent and has a greater yield.


Assuntos
Sulfato de Amônio , Fertilizantes , Nitrogênio , Rizosfera , Microbiologia do Solo , Solo , Ureia , Zea mays , Zea mays/crescimento & desenvolvimento , Solo/química , Ureia/metabolismo , Microbiota/efeitos dos fármacos
13.
Org Lett ; 26(27): 5833-5838, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38934368

RESUMO

Reported herein is a practical, economical, and efficient construction of 3-alkylated quinoxalin-2(1H)-ones with alkyl carboxylic acids and alkyl iodides by quinoxalin-2(1H)-one excitation and cobaloxime catalysis. Primary, secondary, and tertiary alkyl iodides and carboxylic acids all could be efficiently transferred into target products with excellent functional group tolerance. Mechanism studies reveal that the quinoxalin-2(1H)-one derivatives could be directly excited and yield alkyl carbon radicals from alkyl carboxylic acids and alkyl iodides with the aid of the cobaloxime complex.

14.
Br J Pharmacol ; 181(6): 896-913, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37309219

RESUMO

BACKGROUND AND PURPOSE: Overexpression of astrocytic lactoferrin (Lf) was observed in the brain of Alzheimer's disease (AD) patients, whereas the role of astrocytic Lf in AD progression remains unexplored. In this study, we aimed to evaluate the effects of astrocytic Lf on AD progression. EXPERIMENTAL APPROACH: Male APP/PS1 mice with astrocytes overexpressing human Lf were developed to evaluate the effects of astrocytic Lf on AD progression. N2a-sw cells also were employed to further uncover the mechanism of astrocytic Lf on ß-amyloid (Aß) production. KEY RESULTS: Astrocytic Lf overexpression increased protein phosphatase 2A (PP2A) activity and reduced amyloid precursor protein (APP) phosphorylation, Aß burden and tau hyperphosphorylation in APP/PS1 mice. Mechanistically, astrocytic Lf overexpression promoted the uptake of astrocytic Lf into neurons in APP/PS1 mice, and conditional medium from astrocytes overexpressing Lf inhibited p-APP (Thr668) expression in N2a-sw cells. Furthermore, recombinant human Lf (hLf) significantly enhanced PP2A activity and inhibited p-APP expression, whereas inhibition of p38 or PP2A activities abrogated the hLf-induced p-APP down-regulation in N2a-sw cells. Additionally, hLf promoted the interaction of p38 and PP2A via p38 activation, thereby enhancing PP2A activity, and low-density lipoprotein receptor-related protein 1 (LRP1) knockdown significantly reversed the hLf-induced p38 activation and p-APP down-regulation. CONCLUSIONS AND IMPLICATIONS: Our data suggested that astrocytic Lf promoted neuronal p38 activation, via targeting to LRP1, subsequently promoting p38 binding to PP2A to enhance PP2A enzyme activity, which finally inhibited Aß production via APP dephosphorylation. In conclusion, promoting astrocytic Lf expression may be a potential strategy against AD. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Humanos , Masculino , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Camundongos Transgênicos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Proteína Fosfatase 2/metabolismo , Lactoferrina/farmacologia , Astrócitos/metabolismo , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de Doenças , Presenilina-1/metabolismo
15.
Pflugers Arch ; 465(10): 1439-49, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23686296

RESUMO

Transient receptor potential (TRP) channels are not well understood in human atrium, and the present study was therefore designed to investigate whether TRPC channels would mediate the nonselective cation current reported previously and are involved in the formation of store-operated Ca(2+) entry (SOCE) channels in human atrial myocytes using approaches of whole-cell patch voltage-clamp, RT-PCR, Western blotting, co-immunoprecipitation, and confocal scanning approaches, etc. We found that a nonselective cation current was recorded under K(+)-free conditions in human atrial myocytes, and the current was inhibited by the TRP channel blocker La(3+). Thapsigargin enhanced the current, and its effect was suppressed by La(3+) and prevented by pipette inclusion of anti-TRPC1 antibody. Endothlin-1 and angiotensin II enhanced the current that could be inhibited by La(3+). Gene and protein expression of TRPC1 channels were abundant in human atria. In addition, mRNA and protein of STIM1 and Orai1, components of SOCE channels, were abundantly expressed in human atria. Co-immunoprecipitation analysis demonstrated an interaction of TRPC1 with STIM1 and/or Orai1. Ca(2+) signaling mediated by SOCE channels was detected by a confocal microscopy technique. These results demonstrate the novel evidence that TRPC1 channels not only mediate the nonselective cation current, but also form SOCE channels in human atria as a component. TRPC1 channels can be activated by endothelin-1 or angiotensin II, which may be involved in the atrial electrical remodeling in patients with atrial fibrillation.


Assuntos
Átrios do Coração/metabolismo , Miócitos Cardíacos/metabolismo , Canais de Cátion TRPC/metabolismo , Potenciais de Ação , Angiotensina II/farmacologia , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Células Cultivadas , Endotelina-1/farmacologia , Átrios do Coração/citologia , Humanos , Lantânio/farmacologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteína ORAI1 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Molécula 1 de Interação Estromal , Canais de Cátion TRPC/antagonistas & inibidores , Canais de Cátion TRPC/genética , Tapsigargina/farmacologia
16.
Int J Clin Oncol ; 18(3): 517-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22610754

RESUMO

BACKGROUND: We aimed to evaluate the association of preoperative plasma fibrinogen levels with the clinicopathological parameters, disease-free survival, and overall survival in patients with renal cell carcinoma. METHODS: We retrospectively studied 286 patients with renal cell carcinoma who underwent radical nephrectomy from 2000 to 2003 at one center. The plasma fibrinogen was routinely determined before operation in all patients. The correlation of preoperative plasma fibrinogen levels with clinicopathological findings was evaluated by t-test or analysis of variance (ANOVA) methods. As well, univariate and multivariate analyses were used to determine the association between the preoperative level of plasma fibrinogen and survival duration. RESULTS: An elevated level of plasma fibrinogen was positively related to the Fuhrman grade (P < 0.001), tumor size (P < 0.001), and T stage (P < 0.001), but it was negatively related to histologic type (P = 0.266). Univariate analysis showed that the Fuhrman grade, tumor size, T stage, hemoglobin, corrected calcium, lactate dehydrogenase, and plasma fibrinogen level were significantly correlated with disease-free survival (P < 0.001, P < 0.001, P < 0.001, P < 0.001, P = 0.001, P < 0.001, and P < 0.001, respectively) and overall survival (P < 0.001, P = 0.001, P < 0.001, P < 0.001, P = 0.002, P = 0.001, and P < 0.001). Multivariate analysis showed that the plasma fibrinogen level remained as an independent prognostic factor for disease-free survival (P = 0.021) and overall survival (P < 0.001). CONCLUSIONS: A high preoperative plasma fibrinogen level is an independent predictor of distant metastasis and survival prognosis after radical nephrectomy in patients with renal cell carcinoma.


Assuntos
Carcinoma de Células Renais/patologia , Fibrinogênio/metabolismo , Neoplasias Renais/patologia , Plasma/metabolismo , Adulto , Idoso , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Renais/sangue , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Período Pré-Operatório , Prognóstico , Estudos Retrospectivos
17.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(11): 1006-9, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24507228

RESUMO

OBJECTIVE: To explore the relevant factors of the causes of sexual orientations of gay. METHOD: From March to June 2013, 350 gays were recruited from one music bar and three bath centers where gays frequently visited in Changsha city, by proportional stratified sampling method. Meanwhile, another 332 males who identify themselves as non-homosexuality were also recruited considering the composition of ages, gender and educational background. Questionnaire survey was conducted to all the subjects, with 300 effective ones reclaimed. The questionnaire included the general demographic information, traits of character, the condition of foster in childhood and information of family members. The differences between the gays and non-homosexuality groups were analyzed to explore the causes of the sexual orientations of gays. RESULTS: There were statistical significant differences between gays and non- homosexuality group on following indexes (χ(2) was 59.63, 5.90, 16.01, 84.99, 161.57, 77.77, 112.32, 190.84, 30.10 respectively, all of P < 0.05) :had a tender father and an impervious mother, were physically weak, not agile, physically inactive, attentive to details, highly conservative, not adventurous, and radical in childhood, were raised as girls before the age of 18, liked to dress as girls before the age of 18, don't liked to play toy knives and toy guns before the age of 18, suffered from sexual abuse before the age of 18 (e.g. forced to expose private parts or forced to have sex) by adults, had read or watched books or films about homosexual and experienced sexual pleasure from that before the age of 18. The rate of gays on these indexes was separately 62.3% (187/300), 57.7% (173/300) , 62.3% (187/300) , 63.0% (189/300), 67.3% (202/300) , 62.7% (189/300), 68.0% (204/300), 65.0% (195/300) and the rate on these indexes of non-homosexuality group was separately 21.3% (64/300), 28.0% (84/300) , 25.0% (75/300) , 12.7% (38/300), 31.3% (94/300), 17.7% (53/300) , 12.7% (38/300), 42.7% (128/300) . The rate of gays on these factors:the youngest boy in family, had the father or twin brothers who were homosexual or self identified as gay was 62.7% (188/300), 56.0% (168/300) and 62.0% (18/29) respectively; and the rate was 40.7% (122/300), 4.0% (12/300) and 20.0% (2/10), respectively among non-homosexuality group. The difference showed statistical significance (χ(2) was 34.52, 193.14, 5.27 respectively, all of P < 0.05). CONCLUSION: The correlative factor of sexual orientation of gays maybe was family relationship, tend and education since childhood, psychological characteristics, sexual experience during puberty.


Assuntos
Homossexualidade Masculina/psicologia , Comportamento Sexual , Adulto , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Comportamento Sexual/estatística & dados numéricos , Inquéritos e Questionários
18.
Biochem Pharmacol ; 209: 115443, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36720353

RESUMO

Several clinical trials observed that enzastaurin prolonged QT interval in cancer patients. However, the mechanism of enzastaurin-induced QT interval prolongation is unclear. Therefore, this study aimed to assess the effect and mechanism of enzastaurin on QT interval and cardiac function. The Langendorff and Ion-Optix MyoCam systems were used to assess the effects of enzastaurin on QT interval, cardiac systolic function and intracellular Ca2+ transient in guinea pig hearts and ventricular myocytes. The effects of enzastaurin on the rapid delayed rectifier (IKr), the slow delayed rectifier K+ current (IKs), transient outward potassium current (Ito), action potentials, Ryanodine Receptor 2 (RyR2) and the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2a (SERCA2a) expression and activity in HEK 293 cell system and primary cardiomyocytes were investigated using whole-cell recording technique and western blotting. We found that enzastaurin significantly prolonged QT interval in guinea pig hearts and increased the action potential duration (APD) in guinea pig cardiomyocytes in a dose-dependent manner. Enzastaurin potently inhibited IKr by binding to the human Ether-à-go-go-Related gene (hERG) channel in both open and closed states, and hERG mutant channels, including S636A, S631A, and F656V attenuated the inhibitory effect of enzastaurin. Enzastaurin also moderately decreased IKs. Additionally, enzastaurin also induced negative chronotropic action. Moreover, enzastaurin impaired cardiac systolic function and reduced intracellular Ca2+ transient via inhibition of RyR2 phosphorylation. Taken together, we found that enzastaurin prolongs QT, reduces heart rate and impairs cardiac systolic function. Therefore, we recommend that electrocardiogram (ECG) and cardiac function should be continuously monitored when enzastaurin is administered to cancer patients.


Assuntos
Síndrome do QT Longo , Canal de Liberação de Cálcio do Receptor de Rianodina , Humanos , Animais , Cobaias , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Células HEK293 , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/metabolismo , Miócitos Cardíacos , Potenciais de Ação , Canais de Potássio Éter-A-Go-Go
19.
Basic Res Cardiol ; 107(5): 282, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22802050

RESUMO

Transient receptor potential melastatin-7 (TRPM7) channels have been recently reported in human atrial fibroblasts and are believed to mediate fibrogenesis in human atrial fibrillation. The present study investigates whether TRPM7 channels are expressed in human atrial myocytes using whole-cell patch voltage-clamp, RT-PCR and Western blotting analysis. It was found that a gradually activated TRPM7-like current was recorded with a K(+)- and Mg(2+)-free pipette solution in human atrial myocytes. The current was enhanced by removing extracellular Ca(2+) and Mg(2+), and the current increase could be inhibited by Ni(2+) or Ba(2+). The TRPM7-like current was potentiated by acidic pH and inhibited by La(3+) and 2-aminoethoxydiphenyl borate. In addition, Ca(2+)-activated TRPM4-like current was recorded in human atrial myocytes with the addition of the Ca(2+) ionophore A23187 in bath solution. RT-PCR and Western immunoblot analysis revealed that in addition to TRPM4, TRPM7 channel current, mRNA and protein expression were evident in human atrial myocytes. Interestingly, TRPM7 channel protein, but not TRPM4 channel protein, was significantly increased in human atrial specimens from the patients with atrial fibrillation. Our results demonstrate for the first time that functional TRPM7 channels are present in human atrial myocytes, and the channel expression is upregulated in the atria with atrial fibrillation.


Assuntos
Miócitos Cardíacos/metabolismo , Canais de Cátion TRPM/fisiologia , Fibrilação Atrial/metabolismo , Compostos de Boro/farmacologia , Cálcio/metabolismo , Feminino , Átrios do Coração/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Elementos da Série dos Lantanídeos/farmacologia , Magnésio/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Serina-Treonina Quinases
20.
Yao Xue Xue Bao ; 47(8): 1055-62, 2012 Aug.
Artigo em Zh | MEDLINE | ID: mdl-23162904

RESUMO

The goal of the study is to evaluate the self-microemulsifying drug delivery system (SMEDDS) which enhances the oral bioavailability of the poorly water-soluble drug, total flavones of Hippophae rhamnoides (TFH). It is orally administered for the protection of human cardiovascular system. Self-microemulsifying time, particle size, polydispersity index (PDI), morphological characterization, in vitro dispersity, stability, in situ intestinal absorption and relative bioavailability were investigated in detail. The TFH-SMEDDS rapidly formed fine oil-in-water microemulsions with 0.1 mol x L(-1) hydrochloride solution, with average size of which was less than 40 nm, PDI was below 0.2, and the particles of which were observed round-shaped under transmission electron microscope. Almost 90% of TFH (expressed with quercetin) was released from SMEDDS within 20 min, which was remarkably higher than that from common capsules. The stability test showed the TFH-SMEDDS maintained stable in 6 months under accelerated condition. In situ absorption study demonstrated the absorption rate constant of TFH-SMEDDS (expressed with quercetin) was significantly higher than that of TFH in ethanolic solution (P < 0.05). The absorption of TFH from SMEDDS showed a 4.18-fold increase in relative bioavailability (expressed with quercetin) compared with that of the suspension. The results suggest that SMEDDS is a promising drug delivery system to increase the oral bioavailability of TFH.


Assuntos
Sistemas de Liberação de Medicamentos , Flavonas/farmacocinética , Hippophae/química , Absorção Intestinal , Administração Oral , Animais , Disponibilidade Biológica , Portadores de Fármacos , Emulsões , Flavonas/administração & dosagem , Flavonas/isolamento & purificação , Frutas/química , Masculino , Tamanho da Partícula , Folhas de Planta/química , Plantas Medicinais/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
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