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1.
Molecules ; 29(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38893440

RESUMO

Three different iridium(III) complexes, labelled as Ir1-Ir3, each bearing a unique anchoring moiety (diethyl [2,2'-bipyridine]-4,4'-dicarboxylate, tetraethyl [2,2'-bipyridine]-4,4'-diylbis(phosphonate), or [2,2'-biquinoline]-4,4'-dicarboxylic acid), were synthesized to serve as photosensitizers. Their electrochemical and photophysical characteristics were systematically investigated. ERP measurements were employed to elucidate the impact of the anchoring groups on the photocatalytic hydrogen generation performance of the complexes. The novel iridium(III) complexes were integrated with platinized TiO2 (Pt-TiO2) nanoparticles and tested for their ability to catalyze hydrogen production under visible light. A H2 turnover number (TON) of up to 3670 was obtained upon irradiation for 120 h. The complexes with tetraethyl [2,2'-bipyridine]-4,4'-diylbis(phosphonate) anchoring groups were found to outperform those bearing other moieties, which may be one of the important steps in the development of high-efficiency iridium(III) photosensitizers for hydrogen generation by water splitting. Additionally, toxicological analyses found no significant difference in the toxicity to luminescent bacteria of any of the present iridium(III) complexes compared with that of TiO2, which implies that the complexes investigated in this study do not pose a high risk to the aquatic environment compared to TiO2.

2.
Am Heart J ; 253: 59-66, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35835265

RESUMO

BACKGROUND: Low plasma potassium (p-K) is associated with increased risk of malignant arrhythmia and observational studies indicate protective effects of p-K in the upper reference level. However, randomized clinical studies are needed to document whether actively increasing p-K to high-normal levels is possible and safe and improves cardiovascular outcomes. OBJECTIVE: To investigate if increased p-K reduces the risk of malignant arrhythmia and all-cause death in high-risk patients with a cardiovascular disease treated with an implantable cardioverter defibrillator (ICD) for primary or secondary preventive causes. Secondly, to investigate whether high-normal p-K levels can be safely reached and maintained using already available medications and potassium-rich dietary guidance. METHODS: This is a prospective, randomized, and open-labelled study enrolling patient at high-risk of malignant arrhythmias. According to sample size calculations, 1,000 patients will be randomized 1:1 to either an investigational regiment that aims to increase and maintain p-K at high-normal levels (4.5-5.0 mmol/L) or to usual standard of care and followed for an expected four years. The trial will run until a total of 291 events have occurred providing an α = 0.05 and 1-ß = 0.80. The composite primary endpoint includes ventricular tachycardia >125 bpm lasting >30 seconds, any appropriate ICD-therapy, and all-cause mortality. At present, 739 patients have been randomized. CONCLUSIONS: We present the rationale for the design of the POTCAST trial. The inclusion was initiated 2019 and is expected to be finished 2022. The study will show if easily available treatments to increase p-K may be a new treatment modality to protect against malignant arrythmias.


Assuntos
Arritmias Cardíacas , Doenças Cardiovasculares , Potássio , Arritmias Cardíacas/prevenção & controle , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/terapia , Desfibriladores Implantáveis , Humanos , Potássio/sangue , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Taquicardia Ventricular/terapia
3.
Int J Neurosci ; 132(2): 171-180, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32757877

RESUMO

PURPOSE: The purpose of this study was to explore the significance of the neuregulin-1/ErbB signaling pathway and its effect on Sox10 expression in the course of the differentiation of mouse bone marrow mesenchymal stem cells into Schwann-like cells in vitro. MATERIALS AND METHODS: The experiment was conducted with three groups-control, TAK 165, and HRG-off. In the control group, we used the classical induction method of adding ß-ME, RA, FSK, b-FGF, PDGF, and neuregulin (HRG); the cells were collected on the 7th day. Using the same basic protocol as the control group, the specific ErbB2 inhibitor mubritinib (TAK 165) was added to block the neuregulin-1/ErbB pathway in the TAK 165 group, while HRG was not added in the HRG-off group. We detected the degree of differentiation of stem cells into Schwann-like cells by using RT-PCR to examine the expression of Sox10, NRG-1, ErbB2, ErbB3, and ErbB4 and by using immunofluorescence staining to examine the Schwann cell marker S100B, Glial Fibrillary Acidic Protein (GFAP) and P75. RESULTS: Our results showed that the proliferation of Schwann cells was reduced and apoptosis was increased in the TAK 165 group and the HRG-off group. Sox10 was stably expressed and NRG-1, ErbB2, and ErbB3 increased in the control group. However, the expression of Sox10 in the TAK 165 group was obviously decreased at the end of induced differentiation; meanwhile, the degree of stem cell differentiation also decreased. CONCLUSIONS: the neuregulin-1/ErbB signaling pathway plays an important role in the differentiation of bone marrow mesenchymal stem cells into Schwann-like cells and can promote the maintenance of Sox10 。.


Assuntos
Neuregulina-1 , Células de Schwann , Animais , Diferenciação Celular , Camundongos , Neuregulina-1/metabolismo , Receptor ErbB-4/metabolismo , Fatores de Transcrição SOXE/genética , Fatores de Transcrição SOXE/metabolismo , Transdução de Sinais
4.
Fish Shellfish Immunol ; 58: 669-677, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27725259

RESUMO

Gradually increasing atmospheric CO2 partial pressure (pCO2) has caused an imbalance in carbonate chemistry and resulted in decreased seawater pH in marine ecosystems, termed seawater acidification. Anthropogenic seawater acidification is postulated to affect the physiology of many marine calcifying organisms. To understand the possible effects of seawater acidification on the proteomic responses of a marine crustacean brine shrimp (Artemia sinica) three groups of cysts were hatched and further raised in seawater at different pH levels (8.2 as control and 7.8 and 7.6 as acidification stress levels according to the predicted levels at the end of this century and next century, respectively) for 1, 7 and 14 days followed by examination of the protein expression changes via two-dimensional gel electrophoresis. Searches of protein databases revealed that 67 differential protein spots were altered due to lower pH level (7.6 and 7.8) stress in comparison to control groups (pH 8.2) by mass spectrometry. Generally, these differentially expressed proteins included the following: 1) metabolic process-related proteins involved in glycolysis and glucogenesis, nucleotide/amino acid/fatty acid metabolism, protein biosynthesis, DNA replication and apoptosis; 2) stress response-related proteins, such as peroxiredoxin, thioredoxin peroxidase, 70-kDa heat shock protein, Na/K ATPase, and ubiquinol-cytochrome c reductase; 3) immune defence-related proteins, such as prophenoloxidase and ferritin; 4) cytoskeletal-related proteins, such as myosin light chain, TCP1 subunit 2, tropomyosin and tubulin alpha chain; and 5) signal transduction-related proteins, such as phospholipase C-like protein, 14-3-3 zeta, translationally controlled tumour protein and RNA binding motif protein. Taken together, these data support the idea that CO2-driven seawater acidification may affect protein expression in the crustacean A. sinica and possibly also in other species that feed on brine shrimp in the ecosystem, particularly marine food webs.


Assuntos
Artemia/fisiologia , Proteínas de Artrópodes/genética , Proteoma , Água do Mar/química , Animais , Artemia/genética , Proteínas de Artrópodes/metabolismo , Dióxido de Carbono/análise , Cromatografia Líquida , Eletroforese em Gel Bidimensional , Concentração de Íons de Hidrogênio , Espectrometria de Massas em Tandem
5.
Fish Shellfish Immunol ; 43(1): 181-90, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25555807

RESUMO

The effects of the decline in ocean pH, termed as ocean acidification due to the elevated carbon dioxide in the atmosphere, on calcifying organisms such as marine crustacean are unclear. To understand the possible effects of ocean acidification on the physiological responses of a marine model crustacean brine shrimp, Artemia sinica, three groups of the cysts or animals were raised at different pH levels (8.2 as control; 7.8 and 7.6 as acidification stress according to the predictions for the end of this century and next century accordingly) for 24 h or two weeks, respectively, followed by examination of their hatching success, morphological appearance such as deformity and microstructure of animal body, growth (i.e. body length), survival rate, expression of selected genes (involved in development, immunity and cellular activity etc), and biological activity of several key enzymes (participated in antioxidant responses and physiological reactions etc). Our results clearly demonstrated that the cysts hatching rate, growth at late stage of acidification stress, and animal survival rate of brine shrimp were all reduced due to lower pH level (7.6 & 7.8) on comparison to the control group (pH 8.2), but no obvious change in deformity or microstructure of brine shrimp was present under these acidification stress by microscopy observation and section analysis. In addition, the animals subjected to a lower pH level of seawater underwent changes on their gene expressions, including Spätzle, MyD88, Notch, Gram-negative bacteria binding protein, prophenoloxidase, Apoptosis inhibitor 5, Trachealess, Caveolin-1 and Cyclin K. Meanwhile, several key enzyme activities, including superoxide dismutase, catalase, peroxidase, alkaline phosphatase and acid phosphatase, were also affected by acidified seawater stress. Taken together, our findings supports the idea that CO2-driven seawater acidification indeed has a detrimental effect, in case of hatching success, growth and survival, on a model crustacean brine shrimp, which will increase the risk of juvenile brine shrimp and possibly also other crustaceans, as important live feeds for aquaculture being introduced in the ecosystem especially the marine food webs.


Assuntos
Artemia/efeitos dos fármacos , Artemia/fisiologia , Proteínas de Artrópodes/genética , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacologia , Regulação da Expressão Gênica , Água do Mar/química , Animais , Artemia/genética , Proteínas de Artrópodes/metabolismo , Concentração de Íons de Hidrogênio
6.
JAMA Cardiol ; 9(2): 165-172, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38150231

RESUMO

Importance: Recurrent pericarditis is a treatment challenge and often a debilitating condition. Drugs inhibiting interleukin 1 cytokines are a promising new treatment option, but their use is based on scarce biological evidence and clinical trials of modest sizes, and the contributions of innate and adaptive immune processes to the pathophysiology are incompletely understood. Objective: To use human genomics, transcriptomics, and proteomics to shed light on the pathogenesis of pericarditis. Design, Setting, and Participants: This was a meta-analysis of genome-wide association studies of pericarditis from 5 countries. Associations were examined between the pericarditis-associated variants and pericarditis subtypes (including recurrent pericarditis) and secondary phenotypes. To explore mechanisms, associations with messenger RNA expression (cis-eQTL), plasma protein levels (pQTL), and CpG methylation of DNA (ASM-QTL) were assessed. Data from Iceland (deCODE genetics, 1983-2020), Denmark (Copenhagen Hospital Biobank/Danish Blood Donor Study, 1977-2022), the UK (UK Biobank, 1953-2021), the US (Intermountain, 1996-2022), and Finland (FinnGen, 1970-2022) were included. Data were analyzed from September 2022 to August 2023. Exposure: Genotype. Main Outcomes and Measures: Pericarditis. Results: In this genome-wide association study of 4894 individuals with pericarditis (mean [SD] age at diagnosis, 51.4 [17.9] years, 2734 [67.6%] male, excluding the FinnGen cohort), associations were identified with 2 independent common intergenic variants at the interleukin 1 locus on chromosome 2q14. The lead variant was rs12992780 (T) (effect allele frequency [EAF], 31%-40%; odds ratio [OR], 0.83; 95% CI, 0.79-0.87; P = 6.67 × 10-16), downstream of IL1B and the secondary variant rs7575402 (A or T) (EAF, 45%-55%; adjusted OR, 0.89; 95% CI, 0.85-0.93; adjusted P = 9.6 × 10-8). The lead variant rs12992780 had a smaller odds ratio for recurrent pericarditis (0.76) than the acute form (0.86) (P for heterogeneity = .03) and rs7575402 was associated with CpG methylation overlapping binding sites of 4 transcription factors known to regulate interleukin 1 production: PU.1 (encoded by SPI1), STAT1, STAT3, and CCAAT/enhancer-binding protein ß (encoded by CEBPB). Conclusions and Relevance: This study found an association between pericarditis and 2 independent sequence variants at the interleukin 1 gene locus. This finding has the potential to contribute to development of more targeted and personalized therapy of pericarditis with interleukin 1-blocking drugs.


Assuntos
Estudo de Associação Genômica Ampla , Humanos , Masculino , Adolescente , Feminino , Genótipo , Fenótipo , Frequência do Gene , Finlândia
7.
JAMA Cardiol ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39230897

RESUMO

Importance: Understanding of the genetics of accessory atrioventricular pathways (APs) and affiliated arrhythmias is limited. Objective: To investigate the genetics of APs and affiliated arrhythmias. Design, Setting, and Participants: This was a genome-wide association study (GWAS) of APs, defined by International Classification of Diseases (ICD) codes and/or confirmed by electrophysiology (EP) study. Genome-wide significant AP variants were tested for association with AP-affiliated arrhythmias: paroxysmal supraventricular tachycardia (PSVT), atrial fibrillation (AF), ventricular tachycardia, and cardiac arrest. AP variants were also tested in data on other heart diseases and measures of cardiac physiology. Individuals with APs and control individuals from Iceland (deCODE Genetics), Denmark (Copenhagen Hospital Biobank, Danish Blood Donor Study, and SupraGen/the Danish General Suburban Population Study [GESUS]), the US (Intermountain Healthcare), and the United Kingdom (UK Biobank) were included. Time of phenotype data collection ranged from January 1983 to December 2022. Data were analyzed from August 2022 to January 2024. Exposures: Sequence variants. Main Outcomes and Measures: Genome-wide significant association of sequence variants with APs. Results: The GWAS included 2310 individuals with APs (median [IQR] age, 43 [28-57] years; 1252 [54.2%] male and 1058 [45.8%] female) and 1 206 977 control individuals (median [IQR] year of birth, 1955 [1945-1970]; 632 888 [52.4%] female and 574 089 [47.6%] male). Of the individuals with APs, 909 had been confirmed in EP study. Three common missense variants were associated with APs, in the genes CCDC141 (p.Arg935Trp: adjusted odds ratio [aOR], 1.37; 95% CI, 1.24-1.52, and p.Ala141Val: aOR, 1.55; 95% CI 1.34-1.80) and SCN10A (p.Ala1073Val: OR, 1.22; 95% CI, 1.15-1.30). The 3 variants associated with PSVT and the SCN10A variant associated with AF, supporting an effect on AP-affiliated arrhythmias. All 3 AP risk alleles were associated with higher heart rate and shorter PR interval, and have reported associations with chronotropic response. Conclusions and Relevance: Associations were found between sequence variants and APs that were also associated with risk of PSVT, and thus likely atrioventricular reentrant tachycardia, but had allele-specific associations with AF and conduction disorders. Genetic variation in the modulation of heart rate, chronotropic response, and atrial or atrioventricular node conduction velocity may play a role in the risk of AP-affiliated arrhythmias. Further research into CCDC141 could provide insights for antiarrhythmic therapeutic targeting in the presence of an AP.

8.
Environ Sci Pollut Res Int ; 30(10): 25863-25872, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36348236

RESUMO

Recently, electrolysis technology has been widely applied in nitrogen and phosphorus removal in river water due to its high efficiency, but its effects on aquatic animals, especially on their neurodevelopmental system, are still unclear. In this study, zebrafish (Danio rerio) embryos were used as model organisms and were put into an electrolytic reaction device with a Ti/IrO2/RuO2 mesh plate as the anode and a Ti mesh plate as the cathode to explore the effects of prolonged electrolysis on the nervous system. The neural development of zebrafish embryos was injured when the current density was greater than 0.89 A/m2. Compared with the control group, the movement speed of zebrafish larvae (120 h postfertilization, hpf) was significantly reduced from 65.48 ± 23.69 to 48.08 ± 22.73 mm/min in a dark environment with an electric current density of 0.89 A/m2 in the electrolysis group. In addition, the acetylcholinesterase activity of zebrafish larvae (120 hpf) gradually decreased from 7.60 ± 0.55 to 6.00 ± 0.01 U/mg prot and the dopamine concentration was reduced from 46.96 ± 0.85 to 40.86 ± 1.05 pg/mL with an electric current density from 0 to 0.89 A/m2 in the electrolysis groups. Furthermore, the expression of nerve-related genes (syn2a, mbp, nestin, and AChE) was significantly inhibited when the current density was more than 0.89 A/m2. However, there were few adverse effects on the neural development of zebrafish embryos when the current density was less than 0.86 A/m2. Thus, a current density of 0.86 A/m2 is a reference value to reduce the harm to the neural development of fish when electrolysis technology is used in river water pollutant treatment.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/genética , Acetilcolinesterase/metabolismo , Eletrólise , Larva , Poluentes Químicos da Água/metabolismo , Embrião não Mamífero
9.
Int J Cardiovasc Imaging ; 39(11): 2097-2106, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37470856

RESUMO

Plasma potassium (p-K) in the high-normal range has been suggested to reduce risk of cardiovascular arrythmias and mortality through electrophysiological and mechanical effects on the myocardium. In this study, it was to investigated if increasing p-K to high-normal levels improves systolic- and diastolic myocardial function in patients with low-normal to moderately reduced left ventricular ejection fraction (LVEF). The study included 50 patients (mean age 58 years (SD 14), 81% men), with a mean p-K 3.95 mmol/l (SD 0.19), mean LVEF 48% (SD 7), and mean Global Longitudinal Strain (GLS) -14.6% (SD 3.1) patients with LVEF 35-55% from "Targeted potassium levels to decrease arrhythmia burden in high-risk patients with cardiovascular diseases trial" (POTCAST). Patients were given standard therapy and randomized (1:1) to an intervention that included guidance on potassium-rich diets, potassium supplements, and mineralocorticoid receptor antagonists targeting high-normal p-K levels (4.5-5.0 mmol/l). Echocardiography was done at baseline and after a mean follow-up of 44 days (SD 18) and the echocardiograms were analyzed for changes in GLS, mechanical dispersion, E/A, e', and E/e'. At follow-up, mean difference in changes in p-K was 0.52 mmol/l (95%CI 0.35;0.69), P<0.001 in the intervention group compared to controls. GLS was improved with a mean difference in changes of -1.0% (-2;-0.02), P<0.05 and e' and E/e' were improved with a mean difference in changes of 0.9 cm/s (0.02;1.7), P = 0.04 and ? 1.5 (-2.9;-0.14), P = 0.03, respectively. Thus, induced increase in p-K to the high-normal range improved indices of systolic and diastolic function in patients with low-normal to moderately reduced LVEF.


Assuntos
Disfunção Ventricular Esquerda , Função Ventricular Esquerda , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Arritmias Cardíacas , Miocárdio , Potássio/farmacologia , Valor Preditivo dos Testes , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem
10.
PLoS One ; 18(7): e0288756, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37467227

RESUMO

OBJECTIVE: Hypokalemia is associated with increased risk of arrhythmias and it is recommended to monitor plasma potassium (p-K) regularly in at-risk patients with cardiovascular diseases. It is poorly understood if administration of potassium supplements and mineralocorticoid receptor antagonists (MRA) aimed at increasing p-K also increases intracellular potassium. METHODS: Adults aged≥18 years with an implantable cardioverter defibrillator (ICD) were randomized (1:1) to a control group or to an intervention that included guidance on potassium rich diets, potassium supplements, and MRA to increase p-K to target levels of 4.5-5.0 mmol/l for six months. Total-body-potassium (TBK) was measured by a Whole-Body-Counter along with p-K at baseline, after six weeks, and after six months. RESULTS: Fourteen patients (mean age: 59 years (standard deviation 14), 79% men) were included. Mean p-K was 3.8 mmol/l (0.2), and mean TBK was 1.50 g/kg (0.20) at baseline. After six-weeks, p-K had increased by 0.47 mmol/l (95%CI:0.14;0.81), p = 0.008 in the intervention group compared to controls, whereas no significant difference was found in TBK (44 mg/kg (-20;108), p = 0.17). After six-months, no significant difference was found in p-K as compared to baseline (0.16 mmol/l (-0.18;0.51), p = 0.36), but a significant increase in TBK of 82 mg/kg (16;148), p = 0.017 was found in the intervention group compared to controls. CONCLUSIONS: Increased potassium intake and MRAs increased TBK gradually and a significant increase was seen after six months. The differentially regulated p-K and TBK challenges current knowledge on potassium homeostasis and the time required before the full potential of p-K increasing treatment can be anticipated. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03833089).


Assuntos
Doenças Cardiovasculares , Hipopotassemia , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Potássio/análise , Arritmias Cardíacas , Contagem Corporal Total
11.
Fish Shellfish Immunol ; 33(1): 1-10, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22538350

RESUMO

In the previous study of the mud crab (Scylla paramamosain) hemocyte proteins, which interacted with a bacterium, Vibrio parahaemolyticus, a protein known as antilipopolysaccharide factor (Sp-ALF) was isolated in addition to a serine proteinase homolog (Sp-SPH) protein. In the present study, we further reported the characterization of two isoforms of the mud crab ALF - Sp-ALFs genes (designated as Sp-ALF1 and Sp-ALF2, respectively) based on our previous result. The Sp-ALF1 and Sp-ALF2 cDNA contained 1070 bp and 731 bp, respectively, with 123 deduced amino acid residues. Alignment of deduced amino acid sequences showed that Sp-ALFs possessed high identity with other known ALFs from crustaceans and exhibited an overall similarity of 57.7% to those of ALFs compared. Phylogenetic tree analysis revealed a clear group of each species and also suggested that ALFs from Scylla genus and those from Portunus genus were closely related. Tissue distribution analysis in adult crab implied that both Sp-ALF1 and Sp-ALF2 were mainly expressed in hemocytes. The mRNA transcripts were also found in embryo (I, II, III and V), zoea-I and juvenile crab, but were rarely observed in the megalopa stage. To further identify the biological activity of Sp-ALFs, recombinant proteins (rSp-ALFs: designated as rSp-ALF1 and rSp-ALF2, respectively) were obtained by expression in Pichia pastris, and the synthetic peptide fragments (sSp-ALFs: designated as sSp-ALF1 and sSp-ALF2, respectively) including the putative LPS binding loop were also prepared for antimicrobial test. The results indicated that both rSp-ALFs and sSp-ALFs were highly effective against most of the Gram-positive bacteria and Gram-negative bacteria tested. In contrast to cecropin P1, a membrane integrity assay revealed that Sp-ALFs did not affect the Escherichia coli by disruption of membrane integrity. Additionally, the recombinant Sp-ALFs proteins exhibited strong antiviral activity against an important aquaculture pathogen, white spot syndrome virus, in crustaceans. Taken together, these data suggested that Sp-ALFs might play a key role in immune defense against microbial infection in the mud crab S. paramamosain.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Braquiúros/genética , Sequência de Aminoácidos , Animais , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Astacoidea/citologia , Astacoidea/virologia , Bactérias/efeitos dos fármacos , Sequência de Bases , Braquiúros/classificação , Braquiúros/metabolismo , Braquiúros/microbiologia , Membrana Celular/metabolismo , Células Cultivadas , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Filogenia , Pichia/genética , Isoformas de Proteínas , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência , Vírus da Síndrome da Mancha Branca 1/efeitos dos fármacos
12.
IEEE Trans Image Process ; 31: 5881-5892, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36070259

RESUMO

Multi-modal hashing learns compact binary hash codes by collaborating heterogeneous multi-modal features at both the model training and online retrieval stages to support large-scale multimedia retrieval. Previous multi-modal hashing methods mainly focus on supervised and unsupervised hashing. The performance of supervised hashing largely relies on the number of labeled data, which is practically expensive to obtain. Unsupervised hashing methods cannot effectively capture the semantic correlations of multi-modal data without any labels for supervision. In this paper, we propose an Efficient Semi-supervised Multi-modal Hashing with Importance Differentiation Regression (ESMH-IDR) model, which can alleviate the existing problems by learning from both labeled and unlabeled data. Specifically, in this paper, we develop an efficient semi-supervised multi-modal hash code learning module. It learns the hash codes for labeled data in an efficient asymmetric way, and simultaneously performs nonlinear regression using the same projection matrix as the labeled samples to preserve the intrinsic data structure of unlabeled data. Besides, different from existing methods, we propose an importance differentiation regression strategy to learn hash functions by specially considering the different importance of hash codes learned from the labeled and unlabeled samples. Finally, we develop an efficient discrete optimization method guaranteed with convergence to iteratively solve the hash optimization problem. Experiments on several public multimedia retrieval datasets demonstrate the superiority of our proposed method on both retrieval effectiveness and efficiency. Our source codes and testing datasets can be obtained at https://github.com/ChaoqunZheng/ESMH.

13.
Artigo em Inglês | MEDLINE | ID: mdl-35131430

RESUMO

Adult zebrafish (Danio rerio) were electrolyzed at different current densities to explore the effects of electrolysis on their reproductive system, especially on embryo production, and to uncover the molecular mechanism of changes in sex hormone and vitellogenin (VTG) levels. The results showed that embryo reproduction of zebrafish was reduced at a current density of 0.64 A/m2 after 28 days of exposure. In addition, the 17ß-estradiol concentration significantly decreased and the testosterone concentration increased in female zebrafish above 0.53 A/m2. However, opposite trends were observed in male zebrafish. The VTG concentration was reduced considerably in the livers of female zebrafish in the 0.64 A/m2 electrolysis group (p < 0.05). In addition, the mRNA expression of hormone-regulating genes was significantly altered in female and male zebrafish when the current density was greater than 0.53 A/m2, and their change trends were sex-dependent. The genes expression levels of vtg1 and esr1 were downregulated in female zebrafish. However, the gene expression of esr1 and cyp19a was upregulated in male zebrafish. These changes were related to disruption in the hormone balance and VTG levels of adult zebrafish. Thus, electrolysis could cause masculinization of female zebrafish and feminization of male zebrafish. Nonetheless, there were few influences on the hormone levels and reproduction rate of adult zebrafish at the threshold of 0.26 A/m2. Thus, the current density of electrolysis needs to be controlled within a specific range to reduce its harmful effects on the reproductive system of aquatic animals.


Assuntos
Eletrólise , Gônadas , Animais , Disruptores Endócrinos , Feminino , Masculino , Reprodução , Fatores Sexuais , Vitelogeninas/genética , Vitelogeninas/metabolismo , Peixe-Zebra
14.
Bioresour Technol ; 320(Pt A): 124324, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33147528

RESUMO

The performance of nitrate removal by Pseudomonas mendocina GL6 cells immobilized on bamboo biochar was investigated. The results showed that immobilized bacterial cells performed better nitrate removal than the free bacterial cells, and the nitrate removal rate increased from 6.51 mg/(L·h) of free cells to 8.34 mg/(L·h) of immobilized cells. The nitrate removal of immobilized bacterial cells fitted well to the zero-order kinetics model. Moreover, bath experiments showed that immobilized bacterial cells displayed more nitrate removal capacity under different conditions than free bacterial cells due to the protection of biochar carrier. The subsequent mechanistic study suggested that biochar promoted the expression level of denitrification functional genes (napA and nirK) and electron transfer genes involved in denitrification (napB and napC), which resulted in the increase of nitrate removal efficiency. Thus, biochar-immobilized P. mendocina GL6 has much potential to remove nitrate from wastewater via aerobic denitrification.


Assuntos
Pseudomonas mendocina , Sasa , Carvão Vegetal , Desnitrificação , Nitratos , Nitrogênio
15.
Environ Sci Pollut Res Int ; 28(46): 66158-66170, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34331223

RESUMO

To improve the nitrogen and phosphorus removal efficiency of surface flow constructed wetlands (SFCWs), biochar was added to an SFCW matrix. The effects of adding different amounts of biochar on water purification, the growth of Vallisneria natans (V. natans), and microbial mechanisms were explored through SFCW simulation experiments. The results showed that through the joint action of biochar and V. natans, the concentrations of total nitrogen, total phosphorus, and ammonia nitrogen in the effluent significantly decreased. The total biomass, relative growth rate, and chlorophyll content of V. natans were significantly reduced by adding biochar (≥20%, v/v), as the root activity and the root to leaf biomass ratio slightly increased at first and then decreased. The carbon and nitrogen contents of V. natans slightly increased with the addition of biochar (≥10%, v/v), but the phosphorus content slightly decreased. Moreover, the nitrogen content of the matrices decreased significantly over time (P<0.05), and the phosphorus content in the matrix showed an increasing trend in the same period. In addition, the microbial 16S rDNA sequencing results indicated that the diversity and abundance of the microbial community in the matrix of the biochar-added SFCW tended to decrease. Nevertheless, the abundance of functional bacteria related to nitrogen and phosphorus removal (i.e., Pseudomonas and Dechloromonas) slightly increased, which would benefit denitrification and dephosphorization in the SFCW. Hence, the addition of biochar to the SFCW matrix facilitated the improvement of effluent water quality, while excessive biochar addition (≥10%, v/v) restrained the growth of V. natans but did not cause death. This conclusion provides valid data support regarding the ability of biochar-added SFCW to purify lightly contaminated water.


Assuntos
Hydrocharitaceae , Áreas Alagadas , Carvão Vegetal , Nitrogênio , Fósforo
16.
Artigo em Inglês | MEDLINE | ID: mdl-33859713

RESUMO

Ganoderma lucidum (Leyss.Fr.) Karst is one of the well-known medicinal macrofungi all over the world, and mounting researches have focused on the polysaccharides derived from the spores of G. lucidum. In the present study, BALB/c mice (n = 8-10) were administered with crude polysaccharides of G. lucidum spores (CPGS) and the refined polysaccharides of G. lucidum spores (RPGS) for 30 days to investigate their effect on the adaptive immune system. Results showed that CPGS and RPGS displayed diverse effects on the lymphocyte activity in the spleen. The splenocyte proliferation activity upon mitogen was suppressed by CPGS and RPGS, while the NK cell's tumor-killing ability was promoted by CPGS. Both CPGS and RPGS could increase the proportion of naïve T cells in thymus, but only RPGS significantly uplifted the percentage of T cells, as well as the T cell subsets, in peripheral blood, and promoted the activation by upregulating the expression of costimulatory factor CD28. Moreover, 16S sequencing results showed that the effects of CPGS and RPGS were closely related to the regulation of gut microbiota. ß-diversity of the microbiome was evidently changed by CPGS and RPGS. The phytoestrogen/polysaccharide-metabolizing bacteria (Adlercreutzia, Parabacteroides, and Prevotella), and an unclassified Desulfovibrionaceae, were remarkably enriched by CPGS or RPGS, and functions involving carbohydrate metabolism, membrane transport, and lipid metabolism were regulated. Moreover, the enrichments of Adlercreutzia, Prevotella, and Desulfovibrionaceae were positively related to the immune regulation by CPGS and RPGS, while that of Parabacteroides displayed a negative correlation. These findings suggested a promising effect of the polysaccharide from sporoderm-broken spore of G. lucidum in immune regulation to promote health control.

17.
Cell Biochem Funct ; 27(8): 535-41, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19918930

RESUMO

Although techniques for purifying epidermal stem cells (ESCs) have been established, enriching a pure population of viable ESCs is still a challenging task. One approach toward enhancing the purity and viability of ESCs involves cell markers. While evidence suggests that p63 plays a role in maintaining the population of ESCs, whether p63 can function as a specific marker for ESCs is unclear. We isolated and cultured oral ESCs and illustrated the expression of p63 and its isoforms in rat oral mucosa tissues and stem cells before and after differentiation. Semi-reverse transcription PCR detected the TA, DeltaN, alpha and beta isoforms when cells were cultured for 2 days, but only TA and gamma were detected after 14 days. We also found that p63 is expressed in basal and suprabasal epithelial layers of rat oral mucosa, but it was implied p63 does not mark stem cells specifically, while the DeltaNp63alpha and DeltaNp63beta isoforms may be specific markers of rat oral mucosa stem cells.


Assuntos
Diferenciação Celular , Mucosa Bucal/citologia , Fosfoproteínas/metabolismo , Células-Tronco/citologia , Transativadores/metabolismo , Animais , Biomarcadores/análise , Ciclo Celular , Células Cultivadas , Masculino , Camundongos , Mucosa Bucal/química , Mucosa Bucal/metabolismo , Células NIH 3T3 , Fosfoproteínas/análise , Fosfoproteínas/genética , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Células-Tronco/química , Células-Tronco/metabolismo , Transativadores/análise , Transativadores/genética
18.
ACS Nano ; 13(1): 440-448, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30586279

RESUMO

Compared with conventional rigid devices, the elastic substrates integrated with functional components offer various advantages, such as flexibility, dynamic tunability, and biocompatibility. However, the reliable formations of 2D nanoparticles, nanogaps, and 3D nanostructures on elastic substrates are still challenging. The conventional transfer method plays an important role in the fabrication of microstructures on elastic substrates; however, it could not fabricate structures with feature size less than a few micrometers. In this article, we have developed a flexible technique based on the "metal-assisted transfer" strategy. The key concept is to introduce a metal film as an assistant layer between nanostructures and silicon substrates to help the fabrication of nanostructures which cannot be successfully transferred in the conventional transfer method. Various 2D nanostructures, which are difficult to achieve on elastic substrates, could be reliably defined using this approach. The desired gap distances and even sub-10 nm metal gaps between adjacent nanoparticles can be controllably achieved. Moreover, 3D nanostructures can be directly assembled from the prestrained 2D precursors based on the developed technique. Comparing with the previous reports, our fabrication method contains only a one-step transfer process without selective bonding or a second transfer process. Significantly, the 3D nanostructures presented here are 2 orders of magnitude smaller than the state-of-the-art mechanically assembled 3D structures in unit cell size. The proposed method may become a mainstream technology for the nano-optics and ultracompact optoelectronic devices due to its multifunctionalities and superior advantages in achieving tunable nanoparticles as well as 3D nanostructures.

19.
ACS Nano ; 13(5): 5583-5590, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31018091

RESUMO

Nanotransfer printing (nTP) technology can generate highly functional three-dimensional (3D) nanostructures in a low-cost and high-throughput fashion. Nevertheless, the fabrication yield and quality of the transferred nanostructures are often limited by the merging of the surface patterns of replica stamps during transfer printing. Here, an nTP technology was developed to fabricate large-area and crack-free 3D multilayer nanostructures. Instead of directly depositing materials on the patterned flexible stamp in conventional nTPs, we transferred the nanostructures straightforwardly onto an attached polydimethylsiloxane slab by removing a sacrificial water-soluble poly(acrylic acid) film, which can avoid the cracking of metal film and the failures of printing nanostructures onto target substrates. Based on this approach, subwavelength-thick polarization rotators working at infrared wavelengths were fabricated. Excellent performance of linear polarization rotation over a broadband was realized. This nTP approach could complement existing fabrication techniques and benefit the development of various functional nanostructures with complex multilayer hierarchies.

20.
Dev Comp Immunol ; 81: 342-347, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29288063

RESUMO

The gradual increase of CO2 concentration in the atmosphere, absorbed by the ocean surface water through air to sea equilibration termed ocean acidification (OA), leads to the decline of pH in seawater. It is not clear so far how the composition of fatty acids, particular the immune-related, in marine crustacean and the subsequent energy supply in marine ecosystem are affected by OA. The brine shrimp Artemia sinica is an open and common feed that provide essential fatty acids for mariculture. In this study, the fatty acids profiles of brine shrimp cultured under different lower pH levels of CO2 driven seawater were investigated. The results showed a significant reduction of the proportion of total saturated fatty acids under the pH7.6 within one week. Meanwhile, the percentage of total monounsaturated fatty acids was significantly decreased at day 14 under pH7.8, and this percentage gave a significant increase of proportion within one week under pH7.6. Furthermore, the relative content of total polyunsaturated fatty acids (PUFAs) was found to be clearly increased with exposure to different seawater acidification at day 1, suggesting that the brine shrimp immune response was likely to be affected by acidified seawater as the PUFAs have been well known to be involved in immunomodulatory effects through alterations on cell membrane fluidity/lipid mediators and gene expression of cell signaling pathways. Notably, eicosapentaenoic acid and docosahexaenoic acid, which have essential effect on various physiological processes such as inflammatory cytokines production and cell structural stability, were strongly increased under two lower pH treatments within one week and with the significant increase at day 1 under pH7.6. These data clearly supported the hypothesis that OA might affect fatty acids composition, likely also the innate immunity, in crustacean and the subsequent energy transfer by food-chain system in the marine ecosystem.


Assuntos
Artemia/fisiologia , Dióxido de Carbono/química , Membrana Celular/metabolismo , Ácidos Graxos/química , Imunidade Inata , Água do Mar/química , Animais , Membrana Celular/química , Ácidos Docosa-Hexaenoicos/química , Ácidos Docosa-Hexaenoicos/metabolismo , Ecossistema , Ácido Eicosapentaenoico/química , Ácido Eicosapentaenoico/metabolismo , Metabolismo Energético , Ácidos Graxos/metabolismo , Cadeia Alimentar , Concentração de Íons de Hidrogênio , Imunomodulação , Inflamação , Biologia Marinha , Oceanos e Mares , Transdução de Sinais
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