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1.
Bull Environ Contam Toxicol ; 113(5): 53, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400598

RESUMO

This study investigated the impacts of polyethylene microplastics (PE-MPs) with varying particle sizes (13 µm and 6.5 µm) on the growth and antioxidant responses of two freshwater algae species, Oscillatoria princeps (O. princeps) and Chlorella pyrenoidosa (C. pyrenoidosa). The results revealed a significant reduction in chlorophyll a content in both algal species upon exposure to PE-MPs, indicating a disruption of photosynthesis. Furthermore, Superoxide Dismutase (SOD) activity decreased in O. princeps, while Catalase (CAT) activity increased in both species, indicating complex physiological responses to microplastic stress. Notably, phycotoxin levels in O. princeps decreased with PE-MP exposure, while those in C. pyrenoidosa increased, particularly with 6.5 µm PE-MPs. These findings underscore the potential toxic effects of PE-MPs on freshwater algal growth and metabolism, as well as their influence on toxin production. This study contributes valuable insights into the ecotoxicological impacts of microplastics in freshwater environments, highlighting the need for further research on their biological effects and environmental health implications.


Assuntos
Chlorella , Microplásticos , Polietileno , Poluentes Químicos da Água , Chlorella/efeitos dos fármacos , Chlorella/crescimento & desenvolvimento , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Polietileno/toxicidade , Clorofila A/metabolismo , Superóxido Dismutase/metabolismo , Fotossíntese/efeitos dos fármacos , Catalase/metabolismo , Clorofila/metabolismo
2.
Analyst ; 143(1): 323-331, 2017 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-29192910

RESUMO

Copper ions (Cu2+) play a critical role in biological processes and are directly involved in ß-amyloid peptide (Aß) aggregation, which is responsible for the occurrence and development of Alzheimer's disease (AD). Therefore, combined determination of Cu2+ and Aß in one analytical system is of great significance to understand the exact nature of the AD event. This work presents a novel ratiometric electrochemical biosensor for the dual determination of Cu2+ and Aß1-42. This unique sensor is based on a 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonate) (ABTS) and poly(diallyldimethylammonium chloride) (PDDA)-bi functionalized single-walled carbon nanotubes (ABTS-PDDA/CNTs) composite. The inclusion of ABTS not only enhanced the sensitivity, but it also acted as an inner reference molecule to improve detection accuracy. The specific recognition of Cu2+ was realized by neurokinin B (NKB) coatings on the ABTS-PDDA/CNTs surface to form a [CuII(NKB)2] complex with Cu2+. The ABTS-PDDA/CNTs-NKB modified electrode also displayed an excellent electrochemical response toward the Aß1-42 monomer, when a certain amount of the Aß1-42 monomer was added to Cu2+-contained PBS buffer, which was due to the release of Cu2+ from the [CuII(NKB)2] complex through Aß binding to Cu2+. Meanwhile, our work showed that Cu2+ bound Aß1-42 was concentration-dependent. Consequently, the presented electrochemical approach was capable of quantifying two important biological species associated with AD by one single biosensor, with the detection limits of 0.04 µM for Cu2+ and 0.5 ng mL-1 for Aß1-42, respectively. Finally, the ratiometric electrode was successfully applied for monitoring Cu2+ and Aß1-42 variations in plasma and hippocampus of normal and AD rats.


Assuntos
Peptídeos beta-Amiloides/análise , Técnicas Biossensoriais , Cobre/análise , Nanotubos de Carbono , Doença de Alzheimer , Animais , Técnicas Eletroquímicas , Íons , Fragmentos de Peptídeos , Ratos
3.
Yao Xue Xue Bao ; 50(1): 86-93, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25924481

RESUMO

In order to clarify material basis of effective parts of liangxue tongyu prescription, blood-heat and blood-stasis rat model induced by dry yeast was established. The changes of rectal temperature, blood viscosity and plasma viscosity were used to evaluate the cooling-blood and activating-blood effects of liangxue tongyu prescription and its parts. Compared with the model group, the extract from liangxue tongyu prescription, its volatile oil and n-butanol part could significantly reduce rectal temperature (P<0.01), and also reduce blood viscosity and plasma viscosity to various degrees (P<0.01 or P<0.05). So volatile oil and n-butanol part were primarily identified as effective parts of liangxue tongyu prescription. By using GC-MS with normalization method of area to analyze volatile oil of liangxue tongyu prescription, 70 compounds were identified, accounting for about 92.54%, mainly as ß-asarone, paeonol, α-asarone and shyobunone. 42 compounds such as peony glycosides, tannins, and iridoid glycosides were identified by HPLC-MS techniques and standard comparison. The study determined the effective parts of liangxue tongyu prescription and clarified the chemical composition providing the foundation for further studies on material basis of liangxue tongyu prescription.


Assuntos
Medicamentos de Ervas Chinesas/química , Óleos Voláteis/química , Acetofenonas/química , Derivados de Alilbenzenos , Animais , Anisóis/química , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Ratos , Taninos/química
4.
Front Immunol ; 15: 1451347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39493765

RESUMO

This study aimed to investigate the potential relationship between multiple sclerosis (MS) and coronavirus disease 2019 (COVID-19) outcomes using Mendelian randomization analysis. Specifically, it evaluates whether genetic factors, including the single-nucleotide polymorphism (SNP) rs10191329, influence the susceptibility of MS patients to three COVID-19 outcomes [severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, hospitalized COVID-19, and severe COVID-19]. This study utilized genome-wide association study summary statistics from the International Multiple Sclerosis Genetics Consortium to conduct a Mendelian randomization analysis. SNPs strongly associated with MS were selected to examine their impact on COVID-19 outcomes. The analysis focused on identifying any causal associations between MS and COVID-19 severity, as well as assessing the role of interferon beta (IFNß) treatment in modifying these outcomes. The results suggest a potential association between MS and an increased risk of COVID-19, but individuals carrying the rs10191329 SNP appeared less likely to develop severe COVID-19. This SNP, located within the DYSF-ZNF638 locus, may influence immune responses and MS severity, highlighting its relevance for personalized treatment strategies. Importantly, no significant causal relationship was found between IFNß treatment and the three COVID-19 outcomes, indicating that the findings in treated patients differ from those observed in untreated patients. This suggests that IFNß may offer protective effects against SARS-CoV-2 in MS patients. These findings underscore the importance of genetic factors, such as rs10191329, in shaping the clinical outcomes of MS patients in the context of COVID-19. Further research should explore targeted therapies and personalized approaches for managing MS during the ongoing pandemic.


Assuntos
COVID-19 , Estudo de Associação Genômica Ampla , Interferon beta , Análise da Randomização Mendeliana , Esclerose Múltipla , Polimorfismo de Nucleotídeo Único , SARS-CoV-2 , Humanos , COVID-19/genética , Esclerose Múltipla/genética , SARS-CoV-2/genética , Interferon beta/uso terapêutico , Predisposição Genética para Doença
5.
Polymers (Basel) ; 16(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38675069

RESUMO

Polyether ether ketone (PEEK) is esteemed as a high-performance engineering polymer renowned for its exceptional mechanical properties and thermal stability. Nonetheless, the majority of polymer-based lubricating materials fail to meet the contemporary industrial demands for motion components regarding high speed, heavy loading, temperature resistance, and precise control. Utilizing 3D printing technology to design and fabricate intricately structured components, developing high-performance polymer self-lubricating materials becomes imperative to fulfill the stringent operational requirements of motion mechanisms. This study introduces a novel approach employing 3D printing technology to produce PEEK with varying filling densities and conducting in situ synthesis of zeolitic imidazolate framework (ZIF-8) nanomaterials on its surface to enhance PEEK's frictional performance. The research discusses the synthetic methodology, characterization techniques, and tribological performance evaluation of in situ synthesized ZIF-8 nanomaterials on PEEK surfaces. The findings demonstrate a significant enhancement in frictional performance of the composite material under low-load conditions, achieving a minimum wear rate of 4.68 × 10-6 mm3/N·m compared to the non-grafted PEEK material's wear rate of 1.091 × 10-5 mm3/N·m, an approximately 1.3 times improvement. Detailed characterization and analysis of the worn surface of the steel ring unveil the lubrication mechanism of the ZIF-8 nanoparticles, thereby presenting new prospects for the diversified applications of PEEK.

6.
Org Lett ; 26(9): 1941-1946, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38415590

RESUMO

Chiral spirocyclopropyl ß-lactams are common motifs in bioactive compounds and pharmaceuticals. Here we disclose a diastereoselective and enantioselective hydroborylation and hydrosilylation of spirocyclopropenes, via a Cu-catalyzed desymmetrization strategy, for the rapid preparation of enantio-enriched spirocyclopropyl ß-lactams. The efficient desymmetrization strategy allows the remote control of axial chirality, offering the borylated and silylated products bearing central, spiro, and axial chirality. The combination of multichiral elements would provide a novel motif for biological evaluation in potential drug discovery.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39447327

RESUMO

The effect of dietary protein on fish is widely studied. However, the high-protein diet effects and mechanisms on growth and amino acid metabolism in Procypris merus remain unclear. In this study, we investigated the effect of dietary protein levels (38 %, 44 %, 50 %) on the growth performance and amino acid contents in larvae and juveniles of P. merus. Transcriptome sequencing was used to study the adaptation mechanism of P. merus to a high-protein diet. The final length, specific growth rate, and protein efficiency ratio were remarkably decreased with increasing dietary protein levels, while the amino acid content of the body was significantly increased. In addition, 370,513,858 reads were obtained and assembled into 278,939 unigenes, with an average length of 559 bp. KEGG analysis revealed that differentially expressed genes were mainly involved in protein digestion and absorption, carbohydrate digestion and absorption, starch and sucrose metabolism, and pancreatic secretion. Moreover, high-protein increased the expression of genes involved in trypsin (prss, ctrl, cpa, cpb), peptide transporter (pept), amino acid transporter (b0at1), and gluconeogenesis (g6pase), which could digest and absorb the dietary protein, and converse amino acids into energy, resulting in adaption to a high-protein diet.

8.
Clin Interv Aging ; 19: 109-118, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250175

RESUMO

Purpose: To explore the predictive value of nutritional risk for all-cause death and functional outcomes among elderly acute stroke patients. Patients and Methods: A total of 479 elderly acute stroke patients were enrolled in this study. The nutritional risk of patients was screened by the GNRI and NRS-2002. The primary outcome was all-cause death, and the secondary outcome was poor prognosis defined as a modified Rankin Scale (mRS) score ≥3. Results: Based on the NRS-2002, patients with nutritional risk had a higher risk of all-cause death at 3 months (adjusted OR: 3.642, 95% CI 1.046~12.689) and at 3 years (adjusted OR: 2.266, 95% CI 1.259~4.076) and a higher risk of adverse functional outcomes at 3 months (adjusted OR: 2.748, 95% CI 1.518~4.972. Based on the GNRI, compared to those without nutritional risk, patients with mild malnutrition also had a higher risk of all-cause death at 3 months (adjusted OR: 7.186, 95% CI 1.550~33.315) and at 3 years (adjusted OR: 2.255, 95% CI 1.211~4.199) and a higher risk of adverse functional outcomes at 3 months (adjusted OR: 1.947, 95% CI 1.030~3.680), so patients with moderate and severe malnutrition had a higher risk of all-cause death at 3 months (adjusted OR: 6.535, 95% CI 1.380~30.945) and at 3 years (adjusted OR: 2.498, 95% CI 1.301~4.799) and a higher risk of adverse functional outcomes at 3 months (adjusted OR: 2.213, 95% CI 1.144~4.279). Conclusion: Nutritional risk increases the risk of poor short-term and long-term outcomes in elderly patients with acute stroke. For elderly stroke patients, we should pay attention to early nutritional risk screening, and effective intervention should be provided to improve the prognosis of such patients.


Assuntos
Desnutrição , Pirimidinas , Acidente Vascular Cerebral , Estirenos , Tiofenos , Idoso , Humanos , Seguimentos , China
9.
Med Oncol ; 40(8): 215, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37382687

RESUMO

Focal adhesion kinase (FAK) is a promising therapeutic target for various cancers and its inhibitor development is in full swing. PF-562271 is a classic FAK inhibitor that has shown promising preclinical data and has been found to exhibit an anti-migration effect on some cancer cells. However, its anticancer effect on high-grade serous ovarian cancer (HGSOC) has not been reported. In this study, we evaluated the anti-migration and anti-proliferation effects of PF-562271 against HGSOC SKOV3 and A2780 cells, as well as the underlying mechanism. The results demonstrated that FAK was overexpressed in clinical HGSOC tissues and was positively correlated with the pathological progression of HGSOC. Moreover, HGSOC patients with high FAK expression levels exhibited low survival rates. PF-562271 treatment significantly inhibited the cell adhesion and migration of SKOV3 and A2780 cells by inhibiting p-FAK expression and decreasing the FA surface area. Additionally, PF-562271 treatment inhibited colony formation and induced cell senescence through G1 phase cell cycle arrest mediated DNA replication inhibition. Taken together, the findings demonstrated that FAK inhibitor PF-562271 significantly inhibits HGSOC cell adhesion, migration, and proliferation process through FAK and/or FAK mediated cell cycle arrest, and suggested that PF-562271 could serve as a potential oncotherapeutic agent for HGSOC targeting treatment.


Assuntos
Neoplasias Ovarianas , Feminino , Humanos , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proteína-Tirosina Quinases de Adesão Focal , Pontos de Checagem da Fase G1 do Ciclo Celular , Neoplasias Ovarianas/tratamento farmacológico
10.
Se Pu ; 39(11): 1213-1221, 2021 Nov.
Artigo em Zh | MEDLINE | ID: mdl-34677016

RESUMO

As among the most widely used pesticides in agriculture, plant growth regulators (PGRs) have a positive influence on plants. However, the overuse of PGRs may induce toxicity in food and even be hazardous to human health. Numerous studies have investigated the presence and residues of PGRs on vegetables and fruits. Animal-derived foods are one of the most dominant food sources providing nutrients to fulfil the daily dietary intake, and could also be potentially contaminated by PGRs. However, there is little information on PGR residues in animal-derived foods. Standardization also lacks among the techniques for PGR determination in animal-derived foods, thereby restricting the further establishment of pesticide usage and food safety regulations. Therefore, in this study, a rapid and effective method for analyzing chlormequat chloride, thidiazuron, and paclobutrazol in animal-derived food samples was established. The method primarily involves high performance liquid chromatography-tandem mass spectrometry combined with the use of isotope-labeled internal standards. The extraction and clean-up procedures were based on the QuEChERS method. The analytes were extracted from pork, beef, chicken, pork liver, egg, and milk samples using acetonitrile, followed by 4 g anhydrous magnesium sulfate (MgSO4), and 1 g sodium chloride (NaCl). The supernatant was removed using a mixture of 50 mg N-propyl ethylenediamine (PSA), 50 mg octadecyl silane (C18), and 150 mg MgSO4, and then passed through a 0.22 µm membrane filter before determination. The Agilent ZORBAX Eclipse Plus C18 column (150 mm×3.0 mm, 1.8 µm) was used to separate the analytes under a gradient elution program, with acetonitrile and 5 mmol/L ammonium acetate solution as mobile phases. The analytes were detected by mass spectrometry using the positive and negative electrospray ionization modes under the multiple reaction monitoring mode. Matrix-matched calibration combined with internal standards was used to quantify the PGRs. The linear regression correlation coefficients (r2) for the PGRs were all greater than 0.990 in the corresponding linear concentration ranges. Chlormequat chloride, thidiazuron, and paclobutrazol showed good linearities in the range of 0.1-100 µg/L for the egg and pork liver samples and 0.1-50 µg/L for the pork, beef, and chicken samples. For the milk samples, thidiazuron and paclobutrazol showed good linearities in the range of 0.05-10 µg/L, while chlormequat chloride showed linearity in the range of 0.05-5 µg/L. The limit of detection (LOD) and limit of quantification (LOQ) for each PGR were based on the signal-to-noise (S/N) ratios. Under optimal conditions, the LODs ranged from 0.01 µg/kg to 0.1 µg/kg, where the LOD was defined as the amount of the tested compound that generated an S/N ratio higher than 3. In addition, the LOQs were in the range of 0.5-5 µg/kg, with an S/N ratio higher than 10. The precision and accuracy were evaluated by recovery experiments. At the LOQ, twice the LOQ, and 10 times the LOQ, the mean recoveries were in the range of 70.0%-117.4%, and the relative standard deviations (RSDs) ranged from 0.8% to 16.1%. The results indicated that the proposed method is accurate and reliable. This method is a modification of the QuEChERS method, and is advantageous owing to its simplicity and high sensitivity. The use of matrix-matching calibration curves and internal standards can eliminate matrix interference, thereby increasing the accuracy of the method. This method satisfies the testing requirements for chlormequat chloride, thidiazuron, and paclobutrazol residues in animal-derived foods, and is promising for the determination of other PGRs or other types of pesticides in animal-derived foods.


Assuntos
Reguladores de Crescimento de Plantas , Espectrometria de Massas em Tandem , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Humanos , Isótopos , Padrões de Referência , Extração em Fase Sólida
11.
Channels (Austin) ; 1(2): 102-12, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18690020

RESUMO

L-type calcium channels (Ca(v)1.1-Ca(v)1.4) link Ca(2+) influx to membrane depolarization and serve a critical role in regulating membrane excitability, muscle contraction, hormone secretion, and gene transcription. In many tissues, L-type calcium channel activity (Ca(v)1.1 and Ca(v)1.2) is enhanced by transmitters and hormones that activate the cAMP-dependent protein kinase (PKA), which is largely thought to be mediated via phosphorylation of the pore forming alpha subunit. However, the ability of PKA to regulate Ca(v)1.3 and the sites contributing to effective modulation of channel activity remains to be established. Using HEK 293 cells, we demonstrate that currents carried by the long C-terminal splice variant of Ca(v)1.3 (Ca(v)1.3L) are selectively enhanced compared to the short C-terminal splice variant (Ca(v)1.3S) when the catalytic subunit of PKA is introduced into the cell via the whole-cell recording electrode. However, the persistence of this regulation is dependent on the identity of the auxiliary beta subunit, such that PKA produces only a transient increase in the presence of beta(3) while a persistent increase is observed in the presence of the beta(2a) subunit. Site-directed mutagenesis of consensus PKA phosphorylation sites revealed that Ser1964 and Ser1743 in Ca(v)1.3L were the predominant sites controlling PKA modulation in the presence of the beta(3) and beta(2a) auxiliary subunits, respectively. Therefore, beta subunits determine the contribution of distinct sites within Ca(v)1.3 towards PKA-mediated enhancement of channel activity. These data suggest that auxiliary beta subunits govern the access of signaling enzymes to L-type calcium channels.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Subunidades Proteicas/metabolismo , Animais , Encéfalo/metabolismo , Canais de Cálcio Tipo L/genética , Linhagem Celular , DNA Complementar/genética , Eletrofisiologia , Proteínas de Fluorescência Verde/metabolismo , Átrios do Coração/química , Ventrículos do Coração/química , Humanos , Rim/citologia , Miocárdio/metabolismo , Técnicas de Patch-Clamp , Fosforilação , Plasmídeos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estrutura Terciária de Proteína , Subunidades Proteicas/genética , Ratos , Transfecção
12.
Artigo em Zh | MEDLINE | ID: mdl-12665935

RESUMO

OBJECTIVE: To prepare and apply monoclonal antibodies (McAb) against recombinant human interferon alpha (rHu IFN-alpha). METHODS: Five cell lines (2E9, 4G1, 2A7, 2C9, 4G10) secreting McAbs against rHu IFN-alpha were established by hybridoma technique. RESULTS: All the cell lines secreted monoclonal antibodies stably. Functions of secreting antibodies of the five cell lines lasted for 6 months in BALB/c mice and 8 months in cell culture. The specificity of antibody was constant. The Ig subclasses of the McAbs were IgG1. Anti-IFN McAb affinity purification column was prepared by coupling the anti IFN-alpha McAb to Sepharose 4B. The combining rate reached was higher than 95%. CONCLUSIONS: The highest purification efficiency was obtained by using 4G10 column.


Assuntos
Anticorpos Monoclonais/biossíntese , Interferon Tipo I/imunologia , Animais , Afinidade de Anticorpos , Especificidade de Anticorpos , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Hibridomas/metabolismo , Interferon Tipo I/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes
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