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1.
Water Res ; 254: 121391, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38452528

RESUMO

Elemental sulfur-based denitrification (ESDeN) technology is known as a cost-saving alternative to its heterotrophic counterpart for nutrient removal from organic-deficient water. However, the traditional fixed-bed reactor (FixBR), as an extensively used process, suffers from a low denitrification rate and even performance deterioration during long-term operation. Herein, we proposed a novel elemental sulfur-based denitrifying moving-bed reactor (ESDeN-MovBR), in which a screw rotator was employed to drive the filled sulfur particles to be microfluidized vertically (a state of vertical-loop movement). Our results showed that the ESDeN-MovBR realized much superior and more stable denitrification performance compared to the ESDeN-FixBR, as indicated by 3.09-fold higher denitrification rate and over one order of magnitude lower intermediates (NO2- and N2O) yield, which could last for over 100 days. Further research revealed that the microfluidization of sulfur particles facilitated the expelling of nitrogen bubbles and excessive biomass, resulting in the prolongation of actual hydraulic retention time by over 80 % and could partially explain the higher denitrification rate in ESDeN-MovBR. The remaining contribution to the improvement of denitrification rate was suggested to be result from changes in biofilm properties, in which the biofilm thickness of ESDeN-MovBR was found to be 3.29 times thinner yet enriched with 2.52 times more autotrophic denitrifiers. This study offered a completely new solution to boost up the denitrification performance of ESDeN technology and provided in-depth evidence for the necessity of biofilm thickness control in such technology.


Assuntos
Reatores Biológicos , Desnitrificação , Enxofre , Processos Autotróficos , Nitrogênio , Nitratos
2.
Environ Sci Technol ; 57(43): 16522-16531, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37844031

RESUMO

Reactive fillers consisting of reduced sulfur and iron species (SFe-ReFs) have received increasing attention in tertiary wastewater treatment for nitrate and phosphate coremoval. However, the existing SFe-ReFs suffer from either low performance (e.g., pyrrhotite and pyrite) or unsatisfactory use in terms of combustible risk and residual nonreactive impurities (e.g., sulfur mixing with natural iron ores). Here, we developed a new type of sulfur-siderite composite ReF (SSCReF) with a structure of natural siderite powders eventually embedded into sulfur. SSCReFs exhibited many excellent properties, including higher mechanical strengths and hardness and especially much poorer ignitability compared to pure sulfur. By using SSCReF to construct packed-bed reactors, the highest denitrification and dephosphorization rates reached 829.70 gN/m3/d (25 wt % siderite) and 36.70 gP/m3/d (75 wt % siderite), respectively. Dephosphorization was demonstrated to be dependent on sulfur-driven denitrification, in which the acid produced from the later process promoted Fe(II) dissolution, which then directly combined with phosphate to form vivianite or further converted into phosphate adsorbents (ferrihydrite, a green rust-like compound). Water flush was an effective way to finally wash out these surface deposited Fe-P compounds, as well as those nonreactive impurities (Si and Al-bearing compounds) detached from SSCReF. Such a highly efficient and safe SSCReF holds considerable application potential in secondary effluent polishing.


Assuntos
Desnitrificação , Nitratos , Reatores Biológicos , Enxofre , Ferro , Fosfatos , Nitrogênio , Processos Autotróficos
3.
Front Endocrinol (Lausanne) ; 14: 1131438, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293501

RESUMO

Objective: The aim of this study was to assess whether size for gestational age and dehydroepiandrosterone sulfate (DHEAS) are associated with cardiometabolic risk in central precocious puberty (CPP) girls. Methods: The retrospective study included 443 patients with newly diagnosed CPP. Subjects were categorized by birth weight for gestational age (appropriate [AGA], small [SGA], and large [LGA] for gestational age) and serum DHEAS concentration (high [≥75th percentile] and normal [<75th percentile] DHEAS). Cardiometabolic parameters were examined. Composite cardiometabolic risk (CMR) score was calculated based on BMI, blood pressure, glucose, insulin, triglyceride, and HDL cholesterol. Non-obesity CMR score was computed, omitting the value from BMI. Logistic regression models, general linear models, and partial correlation analyses were used to evaluate associations. Propensity score matching was performed for sensitivity analyses. Results: Overall, 309 patients (69.8%) were born AGA, 80 (18.1%) were born SGA, and 54 (12.2%) were born LGA. Compared with AGA counterparts, CPP girls born SGA were more prone to have elevated HbA1c (adjusted OR = 4.54; 95% CI, 1.43-14.42) and low HDL cholesterol (adjusted OR = 2.33; 95% CI, 1.18-4.61). In contrast, being born LGA was not associated with increased risk for any glucose or lipid derangements. Despite the fact that elevated CMR score was more common among individuals born LGA than AGA (adjusted OR = 1.84; 95% CI, 1.07-4.35), no significant difference was found on non-obesity CMR score (adjusted OR = 0.75; 95% CI, 0.30-1.88). When controlling for age, birth weight SDS, and current BMI-SDS, individuals with high DHEAS exhibited higher HDL cholesterol and apolipoprotein A-1 concentrations and lower triglyceride level and non-obesity CMR score. Furthermore, DHEAS correlated positively with HDL cholesterol and apolipoprotein A-1 and negatively with triglyceride, prominently in girls born SGA, after adjustments for the three abovementioned confounders. Sensitivity analyses corroborated the findings. Conclusion: Among CPP girls, those born SGA were more likely to possess cardiometabolic risk factors compared to their AGA peers. The difference we observed in cardiometabolic risk between individuals born LGA and AGA was driven by BMI. High DHEAS was associated with favorable lipid profile in CPP girls, even in subjects born SGA.


Assuntos
Doenças Cardiovasculares , Puberdade Precoce , Recém-Nascido , Feminino , Humanos , Peso ao Nascer , Sulfato de Desidroepiandrosterona , Estudos Retrospectivos , Idade Gestacional , HDL-Colesterol , Puberdade Precoce/complicações , Apolipoproteína A-I , Recém-Nascido Pequeno para a Idade Gestacional , Triglicerídeos , Glucose , Doenças Cardiovasculares/etiologia
4.
Sci Total Environ ; 855: 158913, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36411604

RESUMO

The sewer system is a significant source of hydrogen sulfide (H2S) and greenhouse gases which has attracted extensive interest from researchers. In this study, a novel combined dosing strategy using nitrate and calcium peroxide (CaO2) was proposed to simultaneously control sulfide and greenhouse gases, and its performance was evaluated in laboratory-scale reactors. Results suggested that the addition of nitrate and CaO2 improved the effectiveness of sulfide control. And the combination index method further proved that nitrate and CaO2 were synergistic in controlling sulfide. Meanwhile, the combination of nitrate and CaO2 substantially reduced greenhouse gas emissions, especially the carbon dioxide (CO2) and methane (CH4). The microbial analysis revealed that the combined addition greatly stimulated the accumulation of nitrate reducing-sulfide oxidizing bacteria (NR-SOB) that participate in anoxic nitrate-dependent sulfide oxidation, while the abundance of heterotrophic denitrification bacteria (hNRB) was reduced significantly. Moreover, the presence of oxygen and alkaline chemicals generated by CaO2 facilitated the inhibition of sulfate-reducing bacteria (SRB) activities. Therefore, the nitrate dosage was diminished significantly. On the other hand, the generated alkaline chemicals promoted CO2 elimination and inhibited the activities of methanogens, leading to a decrease of CO2 and CH4 fluxes, which facilitated elimination of greenhouse effects. The intermittent dosing test showed that the nitrate and CaO2 could be applied intermittently for sulfide removal. And the chemical cost of intermittent dosing strategy was reduced by 85 % compared to the continuous dosing nitrate strategy. Therefore, intermittent dosing nitrate combined with CaO2 is probably an effective and economical approach to control sulfide and greenhouse gases in sewer systems.


Assuntos
Gases de Efeito Estufa , Nitratos , Esgotos/microbiologia , Dióxido de Carbono , Oxirredução , Sulfetos , Óxidos de Nitrogênio
5.
Org Biomol Chem ; 20(42): 8323-8330, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36239281

RESUMO

A chemoenzymatic approach, mimicking the biosynthetic pathway of heparin and heparan sulfate (HS), has been well developed to prepare a series of structurally well-defined heparin oligosaccharides with excellent anticoagulant activity in good overall yields. The current chemoenzymatic synthesis typically begins with an unnatural glycosyl acceptor, p-nitrophenyl glucuronide (GlcA-PNP), which is convenient for detection recovery and purification, although it affords heparin molecules with undesirable structure characteristics. Herein, we describe a facile chemoenzymatic strategy assisted by the specific cleavage of heparinase III for the highly efficient synthesis of an unmodified heparin heptasaccharide which demonstrated potent anticoagulant activity in vitro and commensurate pharmacokinetic profiles with fondaparinux. This successful generic strategy is applicable to the scalable synthesis of diverse HS/heparin molecules with completely natural structural features as promising therapeutic agents.


Assuntos
Anticoagulantes , Heparina de Baixo Peso Molecular , Anticoagulantes/farmacologia , Anticoagulantes/química , Heparina/química , Heparitina Sulfato/química , Oligossacarídeos/química
6.
Children (Basel) ; 9(10)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36291481

RESUMO

Wiedemann-Steiner syndrome (WDSTS) is an autosomal dominant disorder with a broad and variable phenotypic spectrum characterized by intellectual disability, prenatal and postnatal growth retardation, hypertrichosis, characteristic facial features, behavioral problems, and congenital anomalies involving different systems. Here, we report a five-year-old boy who was diagnosed with WDSTS based on the results of Trio-based whole-exome sequencing and an assessment of his clinical features. He had intellectual disability, short stature, hirsutism, and atypical facial features, including a low hairline, down-slanting palpebral fissures, hypertelorism, long eyelashes, broad and arching eyebrows, synophrys, a bulbous nose, a broad nasal tip, and dental/oral anomalies. However, not all individuals with WDSTS exhibit the classic phenotype, so the spectrum of the disorder can vary widely from relatively atypical facial features to multiple systemic symptoms. Here, we summarize the clinical and molecular spectrum, diagnosis and differential diagnosis, long-term management, and care planning of WDSTS to improve the awareness of both pediatricians and clinical geneticists and to promote the diagnosis and treatment of the disease.

7.
Curr Med Sci ; 42(3): 474-482, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35678907

RESUMO

OBJECTIVE: Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder. Emerging evidence suggests that synaptic dysfunction is associated with the onset and progression of AD. Interestingly, Ginkgo biloba extract (EGb) is one of the most frequently investigated herbal medicines for enhancing cognition and alleviating neurodegenerative dementia. This study aimed to investigate the effect and the mechanism of EGb on AD-like synaptic disorders. METHODS: Scopolamine (SCO)-induced rats were used to mimic AD-like memory deficits. Morris water maze test and fear conditioning test were conducted to evaluate the memory status of rats in response to different treatments. Then, the synapse alterations were assessed by Golgi staining, and Western blotting was conducted to assess the protein expression of PSD95, GluN2B, synapsin-1, and synaptophysin. Reverse transcription quantitative polymerase chain reaction was applied to detect the mRNA expression of PSD95 and the levels of miR-1-3p/miR-206-3p. RESULTS: EGb supplement alleviated the learning and memory deficits induced by SCO in behavioral experiments. Moreover, EGb treatment attenuated synaptic damage elicited by SCO, manifested as increased dendritic spine density and the proportion of mushroom-type spines in hippocampal neurons. Further investigation indicated that EGb rescued the expression of synaptic-related proteins, especially PSD95, and decreased the levels of miR-1-3p/miR-206-3p in the rat hippocampus. CONCLUSION: The application of EGb effectively treats SCO-induced memory impairments probably by suppressing miR-1-3p/miR-206-3p and elevating the expression of PSD95.


Assuntos
Doença de Alzheimer , MicroRNAs , Doença de Alzheimer/metabolismo , Animais , Ginkgo biloba , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Extratos Vegetais , Ratos , Escopolamina/efeitos adversos
8.
Pediatr Diabetes ; 23(5): 597-603, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35689450

RESUMO

OBJECTIVE: The Krüppel-like factor 11 (KLF11) gene causes maturity-onset diabetes of the young 7 (MODY7). There are few reports on the clinical and functional characteristics of KLF11 mutations in patients with MODY7, making diagnosis and treatment complicated. RESEARCH DESIGN AND METHODS: We report a novel KLF11 variant associated with MODY7 in a Chinese family. The proband had hyperglycemia at 9 years of age, and his mother had developed diabetes at age 28 years. Both required insulin injections from the initial phase of the disease. They were negative for islet cell autoantibodies and had normal fasting C-peptide levels. We observed changes in the levels of fasting blood glucose, C-peptide, and islet cell autoantibodies in the proband over 4.5 years. RESULTS: Whole-exon sequencing was used to screen the proband and his family members for KLF11 variants. The heterozygous KLF11 variant (c.1045C>T, p. Pro349Ser) was identified in the proband, his mother, his maternal grandmother, and an elderly aunt, although the latter two individuals were unaffected. In silico analyses indicated that this variant involved a change in the amino acid side chain in the transcriptional regulatory domain 3. Luciferase reporter assays revealed that the variant had impaired insulin promoter regulation activity. Moreover, in vitro analyses showed that this variant impaired insulin secretion from pancreatic beta cells. CONCLUSIONS: This study documents a novel heterozygous KLF11 variant (p. Pro349Ser) as a potential monogenic mutation associated with MODY7 in a family. This variant impairs insulin secretion from pancreatic beta cells, possibly by repressing insulin promoter regulation activity.


Assuntos
Diabetes Mellitus Tipo 2 , Proteínas Repressoras , Adulto , Proteínas Reguladoras de Apoptose/genética , Autoanticorpos/genética , Peptídeo C , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus Tipo 2/genética , Feminino , Humanos , Masculino , Mutação , Linhagem , Proteínas Repressoras/química
9.
Sci Total Environ ; 816: 151581, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-34774952

RESUMO

Nitrate dosing is commonly used for controlling hydrogen sulfide in sewer systems. However, it may potentially facilitate N2O emission due to the denitrification process promoted by nitrate addition. In this study, lab-scale sewer reactors were operated to investigate the impact of nitrate addition on N2O production in sewer systems. Results showed that the N2O flux even increased by six times with the addition of nitrate when dissolved oxygen (DO) in the wastewater exceeded 0.4 mg/L. Principal component analysis showed that the N2O concentration was notably affected by DO and oxidation-reduction potential (ORP) in the wastewater. Furthermore, it was founded that N2O flux had a strong linear relationship with the DO concentration in the batch test. The microbial analysis found that the nosZ possessing organisms decreased significantly in the micro-aerobic condition and the copy numbers of nosZ gene declined consequently. It indicated that the inhibition of N2O reduced to N2 was responsible for significant accumulation and emission of N2O in the micro-aerobic condition. Given the gravity sewers are not completely anaerobic, the DO concentration is ranged from 0.1 to 2.4 mg/L in gravity sewers with the partially filled flow. Therefore, more attention should be paid to the N2O production when nitrate dosing for hydrogen sulfide controlling in gravity sewers.


Assuntos
Sulfeto de Hidrogênio , Nitratos , Desnitrificação , Óxidos de Nitrogênio , Óxido Nitroso/análise , Oxigênio/análise , Esgotos
10.
J Hazard Mater ; 424(Pt B): 127527, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34879520

RESUMO

Nitrate has been widely used in sewer systems for sulfide control. However, significant chemical consumption and the loss of carbon source were observed in previous studies. To find a feasible and cost-effective control strategy of the sulfide control, the effect of nitrate combined with sodium nitroprusside (SNP) dosage strategy was tested in lab-scale sewer biofilm reactors. Results showed that nitrate and SNP were strongly synergistic, with 30 mg N/L nitrate and 20 mg/L SNP being sufficient for sulfide control in this study. While large amount of nitrate alone (100 mg N/L) is required to achieve the same sulfide control effectiveness. Meanwhile, the nitrate combined with SNP could reduce the organic carbon source loss by 80%. Additionally, the high-throughput sequencing results showed that the relative abundance of autotrophic, nitrate reducing-sulfide oxidizing bacteria genera (a-NR-SOB) such as Arcobacter and Sulfurimonas was increased by around 18%, while the heterotrophic, nitrate-reducing bacteria (hNRB) such as Thauera was substantially reduced. It demonstrated that the sulfide control was mainly due to the a-NR-SOB activity under the nitrate and SNP dosing strategy. The microbial functional prediction further revealed that nitrate and SNP promoted the dissimilatory nitrate reduction process which utilizes sulfide as an effective electron donor. Moreover, economic assessment indicated that using the combination of nitrate and SNP for sulfide control in sewers would lower the chemical costs by approximately 35% compared with only nitrate addition.


Assuntos
Carbono , Nitratos , Biofilmes , Nitroprussiato , Oxirredução , Sulfetos
11.
Mol Genet Genomic Med ; 9(1): e1533, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33325147

RESUMO

BACKGROUND: Wiedemann-Steiner Syndrome (WSS) is an autosomal dominant genetic condition caused by mutations in the KMT2A gene. Lysine methyltransferase, encoded by KMT2A, plays critical roles in the regulation of gene expression during early development. METHODS: Trio-based whole exome sequencing (Trio-WES) was performed on a 15 months old Chinese girl and her two parents by MyGenostics (Beijing, China) using the Illumina HiSeq X ten system. Variants were confirmed with Sanger sequencing. She exhibited mild/moderate intellectual disability (ID), hypotonia, hypertrichosis cubiti, hypertrichosis on the back, dysmorphic facies, psychomotor retardation, growth delay, small and puffy hands, fat pads anterior to calcanei, and palmar/plantar grooves. RESULTS: Trio-WES revealed a novel de novo mutation of KMT2A gene (NM_001197104.1: c.3566G>T, p.Cys1189Phe). WSS was diagnosed based on WES and clinical features. CONCLUSION: Our findings expand the phenotypic and mutation spectra of WSS.


Assuntos
Anormalidades Múltiplas/genética , Histona-Lisina N-Metiltransferase/genética , Hipertricose/genética , Deficiência Intelectual/genética , Hipotonia Muscular/genética , Proteína de Leucina Linfoide-Mieloide/genética , Anormalidades Múltiplas/patologia , Feminino , Humanos , Hipertricose/patologia , Lactente , Deficiência Intelectual/patologia , Hipotonia Muscular/patologia , Mutação de Sentido Incorreto , Síndrome , Sequenciamento do Exoma
12.
Int J Pharm ; 590: 119947, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33031875

RESUMO

In our previous work, cationic functionalized chitosan was chemically conjugated with superoxide dismutase (SOD) to yield a unique nanoparticle-like conjugate O-HTCC-SOD that has demonstrated superior potential in treating reactive oxygen species (ROS)-related disorders to SOD. Considering contribution of ROS to pathogenesis of osteoarthritis, O-HTCC-SOD was firstly measured for effect on rat chondrocytes exposure to monoiodoacetate (MIA). O-HTCC-SOD was nontoxic to chondrocytes and had more long-acting and intracellular protection effects on chondrocytes against MIA-induced oxidative damage due to its superior elimination of intracellular ROS to SOD. Pharmacokinetic analysis demonstrated that O-HTCC-conjugated SOD significantly prolonged half-life and residence in rat joint cavity, and improved bioavailability compared with unmodified SOD. Intra-articular injection of O-HTCC-SOD significantly attenuated mechanical allodynia in MIA-induced osteoarthritis rats, dramatically suppressed gross morphological and histological lesions of articular cartilage, and greatly enhanced in vivo antioxidant capacity and anti-inflammatory effect. But native SOD had no obvious therapeutic effects. Consequently, the nanoparticle-like conjugate O-HTCC-SOD of the excellent efficacy resulted from its targeted intracellular ROS clearance capability and improved pharmacokinetic profiles, opening up a novel avenue for disease-modifying osteoarthritis drugs.


Assuntos
Quitosana , Nanopartículas , Osteoartrite , Animais , Osteoartrite/induzido quimicamente , Osteoartrite/tratamento farmacológico , Ratos , Espécies Reativas de Oxigênio , Superóxido Dismutase
13.
Environ Sci Pollut Res Int ; 27(24): 30571-30582, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32468370

RESUMO

Odor emissions from sewer systems and wastewater treatment plants have attracted much attention due to the potential negative effects on human health. A single-chamber membrane-free microbial electrolysis cell was proposed for the removal of sulfides in a sewer system. The feasibility of the use of volatile sulfur compounds and their removal efficiency in liquid and headspace gas phases were investigated using synthetic wastewater with real sewer sediment and Ru/Ir-coated titanium electrodes. The results indicate that hydrogen sulfide and volatile organic sulfur compounds were effectively inhibited in the liquid phase upon electrochemical treatment at current densities of 1.55, 2.06, and 2.58 mA/cm2, and their removal rates reached up to 86.2-100%, except for dimethyl trisulfide, the amount of which increased greatly at 1.55 mA/cm2. In addition, the amount of volatile sulfur compounds in the headspace decreased greatly; however, the total theoretical odor concentration was still high, and methanethiol and ethanethiol greatly contributed to the total strength of the odor concentration due to their low odor threshold concentrations. The major pathway for sulfide removal in the single-chamber membrane-free microbial electrolysis cell is biotic oxidation, the removal rate of which was 0.4-0.5 mg/min, 4-5 times that of indirect electrochemical oxidation.


Assuntos
Compostos de Enxofre , Compostos Orgânicos Voláteis , Eletrólise , Odorantes , Sulfetos , Enxofre
14.
Mitochondrial DNA B Resour ; 3(2): 1096-1097, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33474430

RESUMO

Jinbian carp (Cyprinus carpio) is an endemic species in China. The complete mitochondrial genome of Jinbian carp is determined to be 16,581 bp in length and includes 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a control region. Its structural organization and gene order are equivalent to other common carp strains. The phylogenetic analyses will contribute to further insights of the taxonomy and phylogeny in Cyprinidae family.

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