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1.
Hepatology ; 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34624136

RESUMO

BACKGROUND & AIMS: The risk factors of cholelithiasis have not been clearly identified, especially for total cholesterol. Here, we try to identify these causal risk factors. APPROACH & RESULTS: We obtained genetic variants associated with the exposures at the genome-wide significance (p < 5x10-8 ) level from corresponding genome-wide association studies (GWAS). Summary-level statistical data for cholelithiasis were obtained from FinnGen and UK Biobank (UKB) consortia. Both univariable and multivariable Mendelian randomization (MR) analyses were conducted to identify causal risk factors of cholelithiasis. Results from FinnGen and UKB were combined using fixed effect model. In FinnGen, the odds of cholelithiasis increased per 1-SD increase of body mass index (BMI) (OR = 1.631, P = 2.16 x 10-7 ), together with body fat percentage (OR = 2.108, P = 4.56 x 10-3 ) and fasting insulin (OR = 2.340, P = 9.09 x 10-3 ). The odds of cholelithiasis would also increase with lowering of total cholesterol (OR = 0.789, P = 8.34 x 10-5 ) and low-density lipoprotein cholesterol (LDL-C) (OR = 0.792, P = 2.45x10-4 ). However, LDL-C was not significant in multivariable MR. In UKB, the results of BMI, body fat percentage, total cholesterol and LDL-C were replicated. In meta-analysis, the liability to type 2 diabetes mellitus and smoking could also increase the risk of cholelithiasis. Besides, there were no associations with other predominant risk factors. CONCLUSIONS: Our MR study corroborated the risk factors of cholelithiasis from previous MR studies. Furthermore, lower total cholesterol level could be a novel independent risk factor.

2.
BMC Med Genomics ; 14(1): 224, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535143

RESUMO

BACKGROUND: The relationship between serum lipids and cholecystitis is still under investigation. To examine the causal effect of serum lipids on cholecystitis using the Mendelian randomization method. METHODS: We conducted univariable Mendelian randomization (MR) analyses using summary statistics from two independent genome-wide association studies (GWAS) on serum lipids (n = 132,908) and cholecystitis (n = 361,194). Mainly, the inverse-variance weighted (IVW) method was utilized to combine each SNP's causal estimation, and the MR-Egger was adopted as a complementary method, together with the weighted median. Cochrane's Q value was employed to appraise heterogeneity. The MR-Egger intercept and MR-PRESSO were used to detect the horizontal pleiotropy. RESULTS: Our univariable results displayed a minor protective effect of serum low-density lipoprotein (LDL) cholesterol (OR [95% CI] = 0.9984483 [0.9984499, 0.9984468]; p = 0.008) on cholecystitis. No significant causal effect of total cholesterol (TC) (OR [95% CI] = 0.9994228 [0.9994222, 0.9994233]; p = 0.296), triglycerides (OR [95% CI] = 0.9990893 [0.9990882, 0.9990903]; p = 0.238) and high-density lipoprotein (HDL) cholesterol (OR [95% CI] = 0.9997020 [0.9997017, 0.9997023]; p = 0.565) was found on cholecystitis. CONCLUSION: These findings suggest that LDL cholesterolhas a slight protective effect on cholecystitis, which can be easily affected by confounding factors. TC, triglycerides and HDL cholesterol don't have causal effect on cholecystitis. The protective effect of serum lipids on cholecystitis, though possible, remain less certain.

3.
Bioengineered ; 12(1): 7205-7214, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34546847

RESUMO

Schisandrin B is a dibenzocyclooctadiene derivative extracted fromSchisandra chinensis (Turcz.) Baill., that exhibits anti-oxidation, anti-inflammation, anti-tumor and hepatoprotective activities. To understand the hepatoprotective mechanism of schisandrin B, this study investigated the efficacy of schisandrin B on L02 cells after treatment with D-GalN. Following pretreatment with 40 µM schisandrin B, L02 cells were stimulated with 40 mM D-GalN. Cell viability, apoptosis, the expression levels of genes associated with apoptosis, and the intracellular oxidative stress indexes were measured. The viability of L02 cells was determined using MTT assay, and the Annexin V-FITC/PI assay kit was utilized for the assessment of apoptosis. The activities of GSH-Px and SOD, the level of MDA were assessed, separately, using relative detection kits. Moreover, RT-PCR as well as Western blot was applied to measure the mRNA and protein expression of Bax and Bcl-2. The results indicated that schisandrin B significantly prevented D-GalN­induced oxidative damage in L02 cells (P<0.05), decreased GSH-Px and SOD activities (P<0.05), increased MDA content (P<0.05). Furthermore, schisandrin B inhibited D-GalN-induced apoptosis in L02 cells (P<0.05), regulated the expression of Bax and Bcl-2 (P<0.05). The results indicated that schisandrin B decreased the D-GalN-induced intracellular oxidative stress indexes generation, and inhibited the down-regulation of Bcl-2 and up-regulation of Bax induced by D-GalN. In conclusion, schisandrin B was shown to exert protective effect against oxidative damage of L02 cells, which, in part, was achieved by regulating the mRNA and protein levels of Bax and Bcl-2.

4.
Hum Exp Toxicol ; : 9603271211043479, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34591706

RESUMO

BACKGROUND: Bladder cancer (BCa) is a common genitourinary malignancy with higher incidence in males. Long intergenic non-protein coding RNA 265 (LINC00265) is identified as an oncogene in many malignancies, while its role in BCa development remains unknown. PURPOSE: To explore the functions and mechanism of LINC00265 in BCa. RESEARCH DESIGN: Reverse transcription quantitative polymerase chain reaction was performed to examine LINC00265 expression in BCa cells. Cell counting kit-8 assays, colony formation assays, TdT-mediated dUTP Nick-End Labeling assays, and Transwell assays were conducted to examine BCa cell viability, proliferation, apoptosis, and migration. Luciferase reporter assays and RNA immunoprecipitation assays were carried out to explore the binding capacity between miR-4677-3p and messenger RNA fibroblast growth factor 6 (FGF6) (or LINC00265). Xenograft tumor model was established to explore the role of LINC00265 in vivo. RESULTS: LINC00265 was highly expressed in BCa cells. LINC00265 knockdown inhibited xenograft tumor growth and BCa cell viability, proliferation and migration while enhancing cell apoptosis. Moreover, LINC00265 interacted with miR-4677-3p to upregulate the expression of FGF6. FGF6 overexpression reversed the suppressive effect of LINC00265 knockdown on malignant phenotypes of BCa cells. CONCLUSIONS: LINC00265 promotes the viability, proliferation, and migration of BCa cells by binding with miR-4677-3p to upregulate FGF6 expression.

5.
J Invertebr Pathol ; 185: 107657, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34487747

RESUMO

Bacillus thuringiensis (Bt) has been used globally as a biopesticide for effective and environmentally friendly pest control. Research has intensified following the development of resistance by lepidopteran species to Bt insecticidal crystal proteins. Discovering new Bt strains with novel toxin properties which can overcome resistance is one of the strategies to improve pesticide sustainability. The genome of the Bacillus thuringiensis LTS290 strain was sequenced and assembled in 252 contigs containing a total of 6,391,328 bp. The novel cry79Aa1 gene from this strain was identified and cloned. Cry79Aa1 contains 729 amino acid residues and a molecular mass of 84.8 kDa by SDS-PAGE analysis. Cry79Aa1 was found to be active against the lepidopteran larvae of Spodoptera exigua, Helicoverpa armigera, and Plutella xylostella with LC50 values of 13.627 µg/mL, 42.8 µg/mL, and 38.086 µg/mL, respectively. However, Cry79Aa1 protein showed almost no insecticidal activity against Leguminivora glycinivorella, although some degree of growth retardation was observed.

6.
Nucleic Acids Res ; 49(15): 8961-8973, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34365506

RESUMO

Histone recognition constitutes a key epigenetic mechanism in gene regulation and cell fate decision. PHF14 is a conserved multi-PHD finger protein that has been implicated in organ development, tissue homeostasis, and tumorigenesis. Here we show that PHF14 reads unmodified histone H3(1-34) through an integrated PHD1-ZnK-PHD2 cassette (PHF14PZP). Our binding, structural and HDX-MS analyses revealed a feature of bipartite recognition, in which PHF14PZP utilizes two distinct surfaces for concurrent yet separable engagement of segments H3-Nter (e.g. 1-15) and H3-middle (e.g. 14-34) of H3(1-34). Structural studies revealed a novel histone H3 binding mode by PHD1 of PHF14PZP, in which a PHF14-unique insertion loop but not the core ß-strands of a PHD finger dominates H3K4 readout. Binding studies showed that H3-PHF14PZP engagement is sensitive to modifications occurring to H3 R2, T3, K4, R8 and K23 but not K9 and K27, suggesting multiple layers of modification switch. Collectively, our work calls attention to PHF14 as a 'ground' state (unmodified) H3(1-34) reader that can be negatively regulated by active marks, thus providing molecular insights into a repressive function of PHF14 and its derepression.


Assuntos
Histonas/química , Histonas/metabolismo , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/metabolismo , Regulação Alostérica , Animais , Cristalografia por Raios X , Humanos , Modelos Moleculares , Mutagênese , Proteínas Nucleares/química , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Fatores de Transcrição/química , Proteínas de Peixe-Zebra/genética
7.
Theor Appl Genet ; 134(10): 3287-3303, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34410456

RESUMO

KEY MESSAGE: Two CO paralogs in Brassica napus were confirmed and shown distinct expression pattern and function in promoting flowering and allelic variation s within BnaCO.A10 were found closely associated with ecotype divergence. CONSTANS (CO) is a key gene that responds to photoperiod and in Arabidopsis can promote flowering under long-day (LD) conditions. Brassica napus L. is a major oil crop and close relative of Arabidopsis, and arose via allopolyploidization from the diploids B. rapa (A genome) and B. oleracea (C genome). In this study, we confirmed that B. napus has two CO genes located on the A10 (BnaCO.A10) and C9 (BnaCO.C9) chromosomes. Significant differences in level and temporal pattern of transcription, as well as in protein function, of these homoeologous may have resulted from sequence variation in the promoter as well as in the coding region. Apart from two insertions of 527 bp and 2002 bp in the promoter of BnaCO.C9 that function as transcriptional enhancers, this gene is otherwise highly conserved in both promoter and coding region. However, BnaCO.A10 was classified into two haplotypes and transgene analysis in Arabidopsis and backcross analysis in rapeseed indicated that the winter-type haplotype had a greater effect in promoting flowering than the spring type. We discuss the contribution of CO alleles to species evolution, and for eco-geographic radiation following crop domestication, alongside scope for managing this locus in future breeding.


Assuntos
Brassica napus/crescimento & desenvolvimento , Cromossomos de Plantas/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Fenótipo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Alelos , Brassica napus/genética , Mapeamento Cromossômico/métodos , Ecótipo , Evolução Molecular , Flores/genética , Fotoperíodo , Filogenia , Melhoramento Vegetal , Proteínas de Plantas/genética , Locos de Características Quantitativas , Estações do Ano , Fatores de Transcrição/genética
8.
Clin Exp Pharmacol Physiol ; 48(11): 1566-1575, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34363223

RESUMO

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) with a rising incidence worldwide. The precise aetiology is unclear, but aberrant regulatory T cell (Treg) responses have been documented in active UC patients. Follicular regulatory T cell (Tfr) is a recently identified subset of Treg cells. In this study, the role of ICOS in Tfr cells, which is a costimulatory molecule shown to stabilize and promote Treg differentiation, was investigated in UC patients. We found that with increasing UC severity, the frequency of ICOS+ CD4 T cells was increased, but the level of ICOS expression by ICOS+ CD4 T cells was decreased. ICOS+ cells were highly enriched in follicular regulatory T cells (Tfr), which is a subset of Treg cells characterized by CD25+ CD127- CXCR5+ Foxp3+ phenotype. Anti-CD3, anti-CD3/CD28, or anti-CD3/ICOS had all significantly increased the expression of Foxp3 and IL-10, and among the three stimulation methods, anti-CD3/ICOS was most effective at enhancing Foxp3 and IL-10 expression. Moreover, anti-CD3/ICOS-stimulated Tfr cells could suppress conventional T cell proliferation in an IL-10-dependent manner. Interestingly, anti-CD3/ICOS stimulation was less effective in UC-Mild and UC-Active patients compared to that in healthy and UC-Remission patients. In addition, UC patients presented impairment in ICOS upregulation following anti-CD3 stimulation. Overall, these data indicated that ICOS+ Tfr cells were dysregulated in UC patients and the level of dysregulation was associated with the severity of UC, suggesting that ICOS+ Tfr cells could serve as a biomarker of the progression of UC.

9.
Cancer Med ; 10(20): 6985-6997, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34405567

RESUMO

OBJECTIVE: We explored the impact of clinically significant portal hypertension (CSPH) on short- and long-term outcomes of intrahepatic cholangiocarcinoma (ICC) after liver resection (LR). METHODS: Data of 352 ICC patients with cirrhosis who underwent LR were extracted from the Primary Liver Cancer Big Data (PLCBD) between 2005 and 2015 and reviewed. A nomogram based on logistic analyses was developed to illustrate the influencing factors of post-hepatectomy liver failure (PHLF). The impact of CSPH on long-term survival was explored through propensity score matching (PSM) analysis, log-rank test, Cox proportional hazards model, and Kaplan-Meier curves. RESULTS: A total of 106 patients had CSPH, and 246 patients did not. A nomogram established based on GGT level, CSPH, intraoperative blood loss, and multiple tumors had an area under the receiver operating characteristic curve of 0.721 (95% confidence interval [CI] = 0.630-0.812), which displayed a better PHLF predictive value than the MELD score (0.639, 95% CI = 0.532-0.747) and Child-Pugh score (0.612, 95% CI = 0.506-0.719). Moreover, the patients with CSPH had worse overall survival (OS) rates than the patients without CSPH in the whole cohort (p = 0.011) and PSM cohort (p = 0.017). After PSM, multivariable Cox analyses identified that CSPH was an independent risk factor for OS (hazard ratio = 1.585, 95% CI = 1.107-2.269; p = 0.012). CONCLUSION: CSPH is a significant risk factor for PHLF and OS in ICC patients with cirrhosis after surgery. Selecting the proper patients before operation can effectively avoid PHLF and improve the prognosis of ICC.

10.
Food Funct ; 12(15): 6900-6914, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34338268

RESUMO

Ganoderma lucidum (G. lucidum) polysaccharide-1 (GLP-1) is one of the polysaccharides isolated from the fruiting bodies of G. lucidum. Inflammation in the brain-liver axis plays a vital role in the progress of cognitive impairment. In this study, the beneficial effect of GLP-1 on d-galactose (d-gal) rats was carried out by regulating the inflammation of the brain-liver axis. A Morris water maze test was used to assess the cognitive ability of d-gal rats. ELISA and/or western blot analysis were used to detect the blood ammonia and inflammatory cytokines levels in the brain-liver axis. Metabolomic analysis was used to evaluate the changes of small molecule metabolomics between the brain and liver. As a result, GLP-1 could obviously ameliorate the cognitive impairment of d-gal rats. The mechanism was related to the decreasing levels of TNF-α, IL-6, phospho-p38MAPK, phospho-p53, and phospho-JNK1 + JNK2 + JNK3, the increasing levels of IL-10 and TGF-ß1, and the regulation of the metabolic disorders of the brain-liver axis. Our study suggests that G. lucidum could be exploited as an effective food or health care product to prevent and delay cognitive impairment and improve the quality of life.

11.
Adv Drug Deliv Rev ; : 113910, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34358539

RESUMO

Extracellular vesicles (EVs) have shown significant promises as nano-/micro-size carriers in drug delivery and bioimaging. With more characteristics of EVs explored through tremendous research efforts, their unmatched physicochemical properties, biological features, and mechanical aspects make them unique vehicles, owning exceptional pharmacokinetics, circulatory metabolism and biodistribution pattern when delivering theranostic cargoes. In this review we firstly analyzed pros and cons of the EVs as a delivery platform. Secondly, compared to engineered nanoparticle delivery systems, such as biocompatible di-block co-polymers, rational design to improve EVs (exosomes in particular) were elaborated. Lastly, different pharmaceutical loading approaches into EVs were compared, reaching a conclusion on how to construct a clinically available and effective nano-/micro-carrier for a satisfactory medical mission.

13.
Int J Mol Sci ; 22(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34299216

RESUMO

Bifidobacterium bifidum strains, an important component of probiotic foods, can form biofilms on abiotic surfaces, leading to increased self-resistance. However, little is known about the molecular mechanism of B. bifidum biofilm formation. A time series transcriptome sequencing and untargeted metabolomics analysis of both B. bifidum biofilm and planktonic cells was performed to identify key genes and metabolites involved in biofilm formation. Two hundred thirty-five nonredundant differentially expressed genes (DEGs) (including vanY, pstS, degP, groS, infC, groL, yajC, tadB and sigA) and 219 nonredundant differentially expressed metabolites (including L-threonine, L-cystine, L-tyrosine, ascorbic acid, niacinamide, butyric acid and sphinganine) were identified. Thirteen pathways were identified during the integration of both transcriptomics and metabolomics data, including ABC transporters; quorum sensing; two-component system; oxidative phosphorylation; cysteine and methionine metabolism; glutathione metabolism; glycine, serine and threonine metabolism; and valine, leucine and isoleucine biosynthesis. The DEGs that relate to the integration pathways included asd, atpB, degP, folC, ilvE, metC, pheA, pstS, pyrE, serB, ulaE, yajC and zwf. The differentially accumulated metabolites included L-cystine, L-serine, L-threonine, L-tyrosine, methylmalonate, monodehydroascorbate, nicotinamide, orthophosphate, spermine and tocopherol. These results indicate that quorum sensing, two-component system and amino acid metabolism are essential during B. bifidum biofilm formation.


Assuntos
Proteínas de Bactérias/metabolismo , Bifidobacterium bifidum/fisiologia , Biofilmes/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Bifidobacterium bifidum/genética , Bifidobacterium bifidum/metabolismo , Perfilação da Expressão Gênica , Metaboloma , Percepção de Quorum , Transcriptoma , Triticum/microbiologia
14.
Chemosphere ; 281: 131001, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289638

RESUMO

Studies on the symbiosis of microalgae-bacteria have been accelerating as a mean for wastewater remediation. However, there were few reports about the microalgae-bacteria consortia for chemical wastewater treatment. The aim of the present study is to develop an autotrophic and heterotrophic consortium for chemical wastewater treatment and probe whether and how bacteria could benefit from the microalgae during the treatment process, using PTA wastewater as an approach. A process-dependent strategy was applied. First of all, the results showed that the sludge beads with the sludge concentration of 30 g/L were the optimal one with the COD removal rate at 84.8% but the ceiling effect occurred (COD removal rate < 90%) even several common reinforcement methods were applied. Additionally, by adding the microalgae Chlorella vulgaris, a microalgae-activated sludge consortium was formed inside the immobilized beads, which provided better performance to shatter the ceiling effect. The COD remove rate was higher than 90%, regardless of the activated sludge was pre-culture or not. COD removal capacity could also be improved (COD removal rate > 92%) when LEDs light belt was offered as an advanced light condition. Biochemical assay and DNA analysis indicated that the microalgae could form an internal circulation of substances within the activated sludge and drove the microbial community to success and the corresponding gene functions, like metabolism and.


Assuntos
Chlorella vulgaris , Microalgas , Purificação da Água , Biomassa , Nitrogênio , Águas Residuárias
15.
Bioengineered ; 12(1): 4452-4463, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34308746

RESUMO

Dendrobine has been reported to reduce blood lipid levels and apoptosis. The present study was designed to observe the effect of dendrobine in a model of ERS using vascular endothelial cells and to reveal the biological mechanisms and pathways responsible for the therapeutic effects of dendrobine on AS. Human umbilical vein endothelial cells (HUVECs) were pre-treated with various concentrations of dendrobine, followed by treatment with tunicamycin (TM) for the establishment of the cell models of ERS. The proliferation and apoptosis of HUVECs were detected by bromodeoxyuridine staining and flow cytometry, respectively. The target binding association was verified through dual luciferase reporter assay. It was found that TM treatment resulted in a low expression of miR-381-3p. Dendrobine treatment not only promoted the proliferation, but also inhibited the apoptosis of HUVECs induced by TM. The reduced expression of 78-kDa glucose-regulated protein, inositol-requiring enzyme 1, caspase-4, C/EBP homologous protein and caspase-3 was also observed following treatment with dendrobine. Dendrobine reduced the apoptosis of endothelial cells in the model of ERS by increasing miR-381-3p expression, and partially restored the cell proliferation level. This effect was significantly reduced after the expression of miR-381-3p was blocked. On the whole, the present study demonstrated that dendrobine upregulated miR-381-3p expression to inhibit apoptosis induced by ERS in HUVECs and this process was found to be mediated by caspase-4. The findings of the present study may provide new insight into the causes of endothelial cell apoptosis during AS and reveal the potent therapeutic effects of dendrobine in AS.

16.
Zhongguo Zhen Jiu ; 41(7): 789-91, 2021 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-34259413

RESUMO

Professor ZHENG Liang believes that the main pathogenesis of postoperative facial paralysis is related to the retarded circulation of qi and blood and malnutrition of tendons and vessels in local area because of local retention of "stasis" after surgical trauma. In treatment of postoperative facial paralysis with acupotomy, the abnormal facial structure after operation should be considered specially. The region where acupotomy is exerted is determined by taking surgical scar as the center so that the local adhesion can be released and separated. In treatment, the knife needle should be as fine as possible and the attention be paid to the direction of needle insertion and the release amplitude. The frequency of acupotomy should be once per week.


Assuntos
Terapia por Acupuntura , Paralisia Facial , Paralisia Facial/etiologia , Paralisia Facial/terapia , Humanos , Terapias Mente-Corpo , Período Pós-Operatório , Tendões
17.
Anal Chem ; 93(28): 9878-9886, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34229430

RESUMO

Alzheimer's disease (AD) and Parkinson's disease (PD) are chronic neurodegenerative diseases with high morbidity and mortality. Homocysteine (Hcy), cysteine (Cys), and glutathione (GSH) are closely related to AD and PD. However, the dynamics of Hcy, Cys, and GSH in the brain tissues and the potential pathogenesis between Cys/Hcy/GSH with AD and PD remain unclear. Herein, a novel fluorescent probe 1 with multiple binding sites was rationally designed and exploited for the direct quantification of serum total Hcy and Cys along with superior optical properties. Importantly, differentiation and simultaneity fluorescence imaging of Cys, Hcy, and GSH dynamics were achieved in living cells, tissues, and mouse models of AD and PD with this probe, providing direct evidences for the relationship between Hcy/Cys/GSH and AD/PD for the first time. In addition, pathogenesis studies demonstrated that elevated Hcy and Cys levels are closely related to imbalanced redox homeostasis, increased amyloid aggregates, and nerve cell cytotoxicity. These findings will greatly promote the understanding of the functions of Hcy/Cys/GSH in Alzheimer's and Parkinson's diseases, demonstrating clinical promise for the early diagnosis and prevention of AD and PD.


Assuntos
Doença de Alzheimer , Doença de Parkinson , Animais , Cisteína , Corantes Fluorescentes , Glutationa , Células HeLa , Homocisteína , Humanos , Camundongos
18.
Artigo em Inglês | MEDLINE | ID: mdl-34228426

RESUMO

Photocatalytic artificial fixation of N2 to NH3 occurs over NaYF4:Yb,Tm (NYF) upconversion nanoparticles (NPs) decorated carbon nitride nanotubes with nitrogen vacancies (NYF/NV-CNNTs) in water under near-infrared (NIR) light irradiation. NYF NPs with a particle size of ca. 20 nm were uniformly distributed on the surface of NV-CNNTs. The NYF/NV-CNNTs with 15 wt % NYF exhibited the highest NH3 production yield of 1.72 mmol L-1 gcat-1, corresponding to an apparent quantum efficiency of 0.50% under NIR light illumination, and about three times higher the activity of the bare CNNTs under UV-filtered solar light. 15N isotope-labeling NMR results confirm that the N source of ammonia originates from the photochemical N2 reduction. The spectroelectrochemical measurements reveal that NVs can greatly facilitate the photogenerated electron transfer without energy loss, while the presence of NYF NPs shifts both the deep trap state and the edge of conduction band toward a lower potential. Moreover, NYF NPs endow the photocatalyst with a NIR light absorption via the fluorescence resonance energy transfer process, and NVs have the ability to enhance the active sites for a stronger adsorption of N2 and decrease the surface quenching effect of NYF NPs, which thus can promote the energy migration within the heterojunctions. This work opens the way toward full solar spectrum photocatalysis for sustainable ammonia synthesis under aqueous system.

19.
J Pharm Biomed Anal ; 203: 114201, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34130006

RESUMO

Concentrations of arsenic metabolites were important to clarify the sensitivity and resistance of APL (acute promyelocytic leukemia) patients to arsenic trioxide (As2O3). Our purpose was to evaluate levels and distributions of arsenic species in leukocytes and granulocytes of APL patients. Inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were measured by high performance liquid chromatography coupled inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Leukocytes were collected from 21 patients treated with As2O3 during induction, consolidation, and drug-withdrawal period. The upregulation of granulocytes in induction period was closely related to the differentiation of promyelocytes. Therefore, granulocytes were collected during induction period from 4 APL patients and purified by flow cytometry sorting using a panel of monoclonal antibodies specific for CD45, CD3, CD14, and CD19. The developed HPLC-ICP-MS method was precise and accurate with the limit of quantification of 0.5 ng/mL. During induction, consolidation, and drug-withdrawal period, the general trend of arsenic species was iAs > MMA > DMA (P < 0.05) in leukocytes. iAs was predominant arsenic species with median concentration of 10.84 (6.03-14.62) ng/mL. MMA was major methylated metabolite with median concentration of 0.94 (0.60-2.50) ng/mL. Moreover, arsenicals were detected in leukocytes during drug-withdrawal. In granulocytes, iAs was found during induction period with median concentration of 1.08 ng/mL, while MMA and DMA were not detected. These results showed that iAs was the primary arsenic species in leukocytes and granulocytes from APL patients treated with As2O3. This study suggested that iAs might play a dominant therapeutic role during the whole treatment process of APL.


Assuntos
Antineoplásicos , Arsênio , Arsenicais , Leucemia Promielocítica Aguda , Preparações Farmacêuticas , Antineoplásicos/uso terapêutico , Trióxido de Arsênio/uso terapêutico , Cromatografia Líquida de Alta Pressão , Granulócitos , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucócitos
20.
Anal Methods ; 13(25): 2871-2877, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34096941

RESUMO

Carbon monoxide (CO), a gaseous signal molecule, plays a crucial role in biological systems. With the aim of unraveling its biological functions, a novel fluorescent probe for sensing CO was rationally designed and synthesized based on a coumarin derivative fluorophore merging tetrahydroquinoxaline unit and five-membered pyrrolidine. This fluorescent probe demonstrated a large Stokes shift (Δλ = 132 nm), high quantum yield, red emission, high sensitivity and selectivity for CO with remarkable fluorescence turn-on. And the detection limit for CORM-3 is as low as 31.2 nM with the linear range of 0-30 µM. More importantly, this novel probe has been successfully applied to the fluorescence imaging of CO in HepG2 cells and zebrafish, providing a useful approach for the further understanding of the physiological and pathological roles of CO in living systems.


Assuntos
Monóxido de Carbono , Corantes Fluorescentes , Animais , Cumarínicos , Fluorescência , Peixe-Zebra
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