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1.
Environ Sci Technol ; 58(20): 8966-8975, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38722667

RESUMEN

The absolute radical quantum yield (Φ) is a critical parameter to evaluate the efficiency of radical-based processes in engineered water treatment. However, measuring Φ is fraught with challenges, as current quantification methods lack selectivity, specificity, and anti-interference capabilities, resulting in significant error propagation. Herein, we report a direct and reliable time-resolved technique to determine Φ at pH 7.0 for commonly used radical precursors in advanced oxidation processes. For H2O2 and peroxydisulfate (PDS), the values of Φ•OH and ΦSO4•- at 266 nm were measured to be 1.10 ± 0.01 and 1.46 ± 0.05, respectively. For peroxymonosulfate (PMS), we developed a new approach to determine Φ•OHPMS with terephthalic acid as a trap-and-trigger probe in the nonsteady state system. For the first time, the Φ•OHPMS value was measured to be 0.56 by the direct method, which is stoichiometrically equal to ΦSO4•-PMS (0.57 ± 0.02). Additionally, radical formation mechanisms were elucidated by density functional theory (DFT) calculations. The theoretical results showed that the highest occupied molecular orbitals of the radical precursors are O-O antibonding orbitals, facilitating the destabilization of the peroxy bond for radical formation. Electronic structures of these precursors were compared, aiming to rationalize the tendency of the Φ values we observed. Overall, this time-resolved technique with specific probes can be used as a reliable tool to determine Φ, serving as a scientific basis for the accurate performance evaluation of diverse radical-based treatment processes.


Asunto(s)
Radical Hidroxilo , Sulfatos , Sulfatos/química , Radical Hidroxilo/química , Purificación del Agua/métodos , Oxidación-Reducción , Peróxido de Hidrógeno/química
2.
Environ Res ; 262(Pt 2): 119890, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39218338

RESUMEN

The material with high adsorption capacity and selectivity is essential for recovering rare earth elements (REES) from ammonium (NH4+-N)-rich wastewater. Although the emerging metal-organic framework (MOF) has gained intensive attention in REES recovery, there are scientific difficulties unsolved regarding restricted adsorption capacity and selectivity, hindering its extensive engineering applications. In this work, a diethylenetriamine pentaacetic (DTPA)-modified MOF material (MIL-101(Cr)-NH-DTPA) was prepared through an amidation reaction. The MIL-101(Cr)-NH-DTPA showed enhanced adsorption capacity for La(III) (69.78 mg g-1), Eu(III) (103.01 mg g-1) and Er(III) (83.41 mg g-1). The adsorption isotherm and physical chemistry of materials indicated that the adsorption of REEs with MIL-101(Cr)-NH-DTPA was achieved via complexation instead of electrostatic adsorption. Such complexation reaction was principally governed by -COOH instead of -NH2 or -NO2. Meanwhile, the resulting material remained in its superior activity even after five cycles. Such a constructed adsorbent also exhibited excellent selective adsorption activity for La(III), Eu(III), and Er(III), with removal efficiency reaching 70% in NH4+-N concentrations ranging from 100 to 1500 mg L-1. This work offers underlying guidelines for exploitation an adsorbent for REEs recovery from wastewater.

3.
BMC Urol ; 24(1): 207, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39313813

RESUMEN

OBJECTIVE: The influence of robot-assisted radical prostatectomy (RARP) in obese (OB) and non-obese (NOB) prostate cancer patients remains a topic of debate. The objective of this study was to juxtapose the perioperative, functional, and oncologic outcomes of RARP in OB and NOB cohorts. MATERIALS AND METHODS: We systematically searched the databases such as PubMed, Embase, Web of Science, and the Cochrane Library database to identify relevant studies published in English up to September 2023. Review Manager was used to compare various parameters. The study was registered with PROSPERO (CRD42023473136). Sixteen comparative trials were included for 8434 obese patients compared with 55,266 non-obese patients. RESULTS: The OB group had a longer operative time (WMD 17.8 min, 95% CI 9.7,25.8; p < 0.0001), a longer length of hospital stay (WMD 0.18 day, 95% CI 0.12,0.24; p < 0.00001, a higher estimated blood loss (WMD 50.6 ml, 95% CI 11.7,89.6; p = 0.01), and higher pelvic lymphadenectomy rate (RR 1.08, 95% CI 1.04,1.12; p < 0.0001)and lower nerve sparing rate (RR 0.95, 95% CI 0.91,0.99; p < 0.01), but there was no difference between unilateral (RR 1.0, 95% CI 0.8,1.3; p = 0.8)and bilateral (RR 0.9, 95% CI 0.9,1.0; p = 0.06)nerve sparing rate. Then, complication rates (RR 1.6, 95% CI 1.5,1.7; p < 0.00001) were higher in the OB group, and both major (RR 1.4, 95% CI 1.1,1.8; p = 0.01)and minor (RR 1.4, 95% CI 1.1,1.7; p < 0.01)complication rates were higher in the OB group. Moreover, obese patients showed significantly higher probabilities of incontinence (RR 1.17, 95% CI 1.03,1.33; p = 0.01) and impotency (RR 1.08, 95% CI 1.01,1.15; p = 0.02) at 1 year. Last, the positive surgical margin (RR 1.2, 95% CI 1.1,1.3; p < 0.01) was higher in the OB group. CONCLUSION: In the obese group, perioperative outcomes, total complications, functional outcomes, and oncologic outcomes were all worse for RARP. Weight loss before RARP may be a feasible strategy to improve the prognosis of patients.


Asunto(s)
Obesidad , Complicaciones Posoperatorias , Prostatectomía , Neoplasias de la Próstata , Procedimientos Quirúrgicos Robotizados , Humanos , Prostatectomía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Masculino , Neoplasias de la Próstata/cirugía , Obesidad/complicaciones , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento
4.
Acta Pharmacol Sin ; 44(10): 1989-2003, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37268711

RESUMEN

Patients with rheumatoid arthritis (RA) have a much higher incidence of cardiac dysfunction, which contributes to the high mortality rate of RA despite anti-arthritic drug therapy. In this study, we investigated dynamic changes in cardiac function in classic animal models of RA and examined the potential effectors of RA-induced heart failure (HF). Collagen-induced arthritis (CIA) models were established in rats and mice. The cardiac function of CIA animals was dynamically monitored using echocardiography and haemodynamics. We showed that cardiac diastolic and systolic dysfunction occurred in CIA animals and persisted after joint inflammation and that serum proinflammatory cytokine (IL-1ß, TNF-α) levels were decreased. We did not find evidence of atherosclerosis (AS) in arthritic animals even though cardiomyopathy was significant. We observed that an impaired cardiac ß1AR-excitation contraction coupling signal was accompanied by sustained increases in blood epinephrine levels in CIA rats. Furthermore, serum epinephrine concentrations were positively correlated with the heart failure biomarker NT-proBNP in RA patients (r2 = +0.53, P < 0.0001). In CIA mice, treatment with the nonselective ßAR blocker carvedilol (2.5 mg·kg-1·d-1, for 4 weeks) or the specific GRK2 inhibitor paroxetine (2.5 mg·kg-1·d-1, for 4 weeks) effectively rescued heart function. We conclude that chronic and persistent ß-adrenergic stress in CIA animals is a significant contributor to cardiomyopathy, which may be a potential target for protecting RA patients against HF.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Cardiomiopatías , Insuficiencia Cardíaca , Humanos , Ratones , Ratas , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/inducido químicamente , Roedores , Adrenérgicos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Citocinas , Insuficiencia Cardíaca/tratamiento farmacológico , Epinefrina/efectos adversos
5.
BMC Urol ; 23(1): 113, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37420203

RESUMEN

OBJECTIVES: Comparing stone-free rates and associated outcome measures between two surgical modalities of lithotripsy fragmentation and removal or spontaneous passage of dust during retrograde intrarenal surgery (RIRS). METHODS: In March 2023, we conducted a literature search in several widely used databases worldwide, including PubMed, Embase, and Google Scholar. We only considered English articles and excluded pediatric patients. Reviews and protocols without any published data were excluded. We also excluded articles with conference abstracts and irrelevant content. We used the Cochran-Mantel-Haenszel method and random-effects models to assess inverse variances and 95% confidence intervals (CIs) for mean differences in categorical variables. The results were reported as odds ratios (ORs) and 95% CIs. Statistical significance was set at p < 0.05. RESULTS: Our final meta-analysis included nine articles, comprising two randomized controlled trials (RCTs) and seven cohort studies. The total number of patients included in these studies was 1326, and all studies used holmium laser lithotripsy. The pooled analysis of the dust and fragmentation groups showed that the fragmentation group had a higher stone-free rate (OR 0.6; 95% CI 0.41 - 0.89; p = 0.01); the dust group had a shorter operative time (WMD - 11.6 min; 95% CI - 19.56 - -3.63; p = 0.004); and the dust group had a higher retreatment rate (OR 2.03; 95% CI 1.31 - 3.13; p = 0.001). There was no statistically significant difference between the two groups in terms of length of hospital stay, overall complications, or postoperative fever. CONCLUSIONS: Our results showed that both procedures could be safely and effectively used for upper ureteral and renal calculi lithotripsy, the dust group had potential advantages over the fragmentation group in terms of the operation time, and the fragmentation group had certain advantages in terms of stone-free rate and retreatment rate.


Asunto(s)
Cálculos Renales , Litotripsia por Láser , Litotricia , Nefrolitotomía Percutánea , Humanos , Cálculos Renales/cirugía , Riñón/cirugía , Resultado del Tratamiento
6.
Malays J Med Sci ; 30(4): 132-146, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37655149

RESUMEN

Background: Adolescents with syntactic specific language impairment (S-SLI) fail to comprehend which object questions. We hypothesised that rhythmic music training is more effective in treating this condition than conventional methods because music is often perceived as having a clear, isochronous beat or pulse. Thus, this study aims to investigate the effects of rhythmic music training on the syntactic structure processing of Malay which questions among native adolescents. Methods: In this research study, the participants were three groups of Malay adolescents aged 13 years old-15 years old: i) adolescents with S-SLI with music training, ii) adolescents with S-SLI without music training and iii) typically developing adolescents. Before and after music training, the participants were given a sentence-picture matching task. Accuracy measures and reaction times were captured using E-Prime 2.0. Results: The results indicated that with music training, the accuracy and reaction time associated with which object questions among the two SLI groups were significantly higher and lower, respectively. Conclusion: The implications of using rhythmic music training in enhancing syntactic structure processing are also discussed.

7.
Genome Res ; 29(7): 1087-1099, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31175153

RESUMEN

To initiate X-Chromosome inactivation (XCI), the long noncoding RNA Xist mediates chromosome-wide gene silencing of one X Chromosome in female mammals to equalize gene dosage between the sexes. The efficiency of gene silencing is highly variable across genes, with some genes even escaping XCI in somatic cells. A gene's susceptibility to Xist-mediated silencing appears to be determined by a complex interplay of epigenetic and genomic features; however, the underlying rules remain poorly understood. We have quantified chromosome-wide gene silencing kinetics at the level of the nascent transcriptome using allele-specific Precision nuclear Run-On sequencing (PRO-seq). We have developed a Random Forest machine-learning model that can predict the measured silencing dynamics based on a large set of epigenetic and genomic features and tested its predictive power experimentally. The genomic distance to the Xist locus, followed by gene density and distance to LINE elements, are the prime determinants of the speed of gene silencing. Moreover, we find two distinct gene classes associated with different silencing pathways: a class that requires Xist-repeat A for silencing, which is known to activate the SPEN pathway, and a second class in which genes are premarked by Polycomb complexes and tend to rely on the B repeat in Xist for silencing, known to recruit Polycomb complexes during XCI. Moreover, a series of features associated with active transcriptional elongation and chromatin 3D structure are enriched at rapidly silenced genes. Our machine-learning approach can thus uncover the complex combinatorial rules underlying gene silencing during X inactivation.


Asunto(s)
Epigénesis Genética , Silenciador del Gen , Aprendizaje Automático , ARN Largo no Codificante/fisiología , Inactivación del Cromosoma X/genética , Animales , Línea Celular , Células Madre Embrionarias , Femenino , Genes Ligados a X , Genoma , Cinética , Ratones , Modelos Genéticos
8.
Br J Nutr ; 128(4): 762-769, 2022 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-34511145

RESUMEN

The present study aimed to explore the association between dietary patterns in abdominal obesity obtained by reduced-rank regression (RRR) with visceral fat index (VFI) as a dependent variable and dyslipidemia in rural adults in Henan, China. A total of 29538 people aged 18-79 were selected from the Henan Rural Cohort Study. RRR analysis was used to identify dietary patterns; logistic regression analysis and restricted cubic spline regression models were applied to analyze the association between dietary patterns in abdominal obesity and dyslipidemia. VFI was used as a mediator to estimate the mediation effect. The dietary pattern in abdominal obesity was characterized by high carbohydrate and red meat intake and low consumption of fresh fruits, vegetables, milk, etc. After full adjustment, the highest quartile of dietary pattern scores was significantly associated with an increased risk of dyslipidemia (OR: 1·33, 95 % CI 1·23-1·44, Ptrend < 0·001), there was a non-linear dose-response relationship between them (Poverall-association < 0·001, Pnon-lin-association = 0·022). The result was similar in dose-response between the dietary pattern scores and VFI. The indirect effect partially mediated by VFI was significant (OR: 1·07, 95 % CI 1·06-1·08). VIF explained approximately 53·3 % of odds of dyslipidemia related to the dietary pattern. Abdominal obesity dietary pattern scores positively affected VFI and dyslipidemia; there was a dose-response in both relationships. Dyslipidemia progression increased with higher abdominal obesity dietary pattern scores. In addition, VFI played a partial mediating role in relationship between abdominal obesity dietary pattern and dyslipidemia.


Asunto(s)
Dislipidemias , Obesidad Abdominal , Adulto , Humanos , Estudios de Cohortes , Grasa Intraabdominal , Dieta/efectos adversos , Obesidad , China , Factores de Riesgo
9.
Nature ; 535(7613): 575-9, 2016 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-27437574

RESUMEN

X-chromosome inactivation (XCI) involves major reorganization of the X chromosome as it becomes silent and heterochromatic. During female mammalian development, XCI is triggered by upregulation of the non-coding Xist RNA from one of the two X chromosomes. Xist coats the chromosome in cis and induces silencing of almost all genes via its A-repeat region, although some genes (constitutive escapees) avoid silencing in most cell types, and others (facultative escapees) escape XCI only in specific contexts. A role for Xist in organizing the inactive X (Xi) chromosome has been proposed. Recent chromosome conformation capture approaches have revealed global loss of local structure on the Xi chromosome and formation of large mega-domains, separated by a region containing the DXZ4 macrosatellite. However, the molecular architecture of the Xi chromosome, in both the silent and expressed regions,remains unclear. Here we investigate the structure, chromatin accessibility and expression status of the mouse Xi chromosome in highly polymorphic clonal neural progenitors (NPCs) and embryonic stem cells. We demonstrate a crucial role for Xist and the DXZ4-containing boundary in shaping Xi chromosome structure using allele-specific genome-wide chromosome conformation capture (Hi-C) analysis, an assay for transposase-accessible chromatin with high throughput sequencing (ATAC-seq) and RNA sequencing. Deletion of the boundary disrupts mega-domain formation, and induction of Xist RNA initiates formation of the boundary and the loss of DNA accessibility. We also show that in NPCs, the Xi chromosome lacks active/inactive compartments and topologically associating domains (TADs), except around genes that escape XCI. Escapee gene clusters display TAD-like structures and retain DNA accessibility at promoter-proximal and CTCF-binding sites. Furthermore, altered patterns of facultative escape genes indifferent neural progenitor clones are associated with the presence of different TAD-like structures after XCI. These findings suggest a key role for transcription and CTCF in the formation of TADs in the context of the Xi chromosome in neural progenitors.


Asunto(s)
Cromosomas de los Mamíferos/metabolismo , Inactivación del Cromosoma X , Cromosoma X/metabolismo , Alelos , Animales , Sitios de Unión , Factor de Unión a CCCTC , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Cromosomas de los Mamíferos/química , Cromosomas de los Mamíferos/genética , Células Madre Embrionarias/metabolismo , Femenino , Silenciador del Gen , Masculino , Ratones , Células-Madre Neurales/metabolismo , Regiones Promotoras Genéticas/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas Represoras/metabolismo , Análisis de Secuencia , Transcripción Genética , Cromosoma X/química , Cromosoma X/genética , Inactivación del Cromosoma X/genética
10.
Wound Repair Regen ; 28(6): 772-779, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32856346

RESUMEN

Impaired wound healing is a common complication of diabetes. In diabetic wounds, macrophages present dysfunctional efferocytosis and abnormal phenotypes, which could result in excessive neutrophil accumulation and prolonged inflammation, thereby eventually hindering wound repair. ANXA1 N-terminal peptide Ac2-26 exhibits a high potential in mitigating inflammation and improving repair; however, its efficacy in diabetic wound repair remains unclear. In this study, a cutaneous excisional wound model was built in genetically diabetic mice. Ac2-26 or a vehicle solution was employed locally in wound sites. Subsequently, wound zones were measured and sampled at different time intervals post-wounding. Using hematoxylin-eosin and Masson's trichrome staining, we observed the histopathological variations and collagen deposition in wound samples. Based on immunohistochemistry and immunofluorescence, the numbers of neutrophils, macrophages, and CD206-positive macrophages in the wound samples were determined. Cytokine expression in wound samples was studied by immunoblot assay. Results showed that Ac2-26 treatment could facilitate diabetic wound closure, down-regulate the number of neutrophils, and improve angiogenesis and collagen deposition. In addition, Ac2-26 application expedited macrophage recruitment and up-regulated the percentage of macrophages expressing CD206, which is a marker for M2 macrophages. Moreover, Ac2-26 inhibited the expressions of TNF-α and IL-6 and up-regulated the expressions of IL-10, TGF-ß, and VEGFA during diabetic wound healing. Hence, based on the aforementioned findings, Ac2-26 application in diabetic wounds could exert anti-inflammatory and pro-repair effects by reducing neutrophil accumulation and facilitating M2 macrophage development.


Asunto(s)
Anexina A1/farmacología , Diabetes Mellitus Experimental/complicaciones , Macrófagos/patología , Péptidos/farmacología , Piel/lesiones , Traumatismos de los Tejidos Blandos/tratamiento farmacológico , Cicatrización de Heridas/efectos de los fármacos , Animales , Citocinas/metabolismo , Diabetes Mellitus Experimental/patología , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Piel/efectos de los fármacos , Piel/patología , Traumatismos de los Tejidos Blandos/complicaciones , Traumatismos de los Tejidos Blandos/patología , Resultado del Tratamiento
11.
BMC Nephrol ; 21(1): 115, 2020 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-32245423

RESUMEN

BACKGROUND: This study was conducted to evaluate and update the current prevalence of and risk factors for chronic kidney disease (CKD) and diabetic kidney disease (DKD) in a central Chinese urban population. METHODS: From December 2017 to June 2018, a total of 5231 subjects were randomly enrolled from 3 communities in 3 districts of Zhengzhou. CKD was defined as estimated glomerular filtration rate (eGFR) < 60 mL/min.1.73m2 or urinary albumin to creatinine ratio ≥ 30 mg/g (albuminuria). Diabetic subjects with systolic blood pressure > 140 mmHg, albuminuria or an eGFR less than 60 mL/min/1.73 m2 were classified as having DKD. Participants completed a questionnaire assessing lifestyle and relevant medical history, and blood and urine specimens were taken. Serum creatinine, uric acid, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein and urinary albumin were assessed. The age- and sex-adjusted prevalences of CKD and DKD were calculated, and risk factors associated with the presence of reduced eGFR, albuminuria, DKD, severity of albuminuria and progression of reduced renal function were analyzed by binary and ordinal logistic regression. RESULTS: The overall adjusted prevalence of CKD was 16.8% (15.8-17.8%) and that of DKD was 3.5% (3.0-4.0%). Decreased renal function was detected in 132 participants (2.9, 95% confidence interval [CI]: 2.5-3.2%), whereas albuminuria was found in 858 participants (14.9, 95% CI: 13.9-15.9%). In all participants with diabetes, the prevalence of reduced eGFR was 6.3% (95% CI = 3.9-8.6%) and that of albuminuria was 45.3% (95% CI = 40.4-50.1%). The overall prevalence of CKD in participants with diabetes was 48.0% (95% CI = 43.1-52.9%). The results of the binary and ordinal logistic regression indicated that the factors independently associated with a higher risk of reduced eGFR and albuminuria were older age, sex, smoking, alcohol consumption, overweight, obesity, diabetes, hypertension, dyslipidemia and hyperuricemia. CONCLUSIONS: Our study shows the current prevalence of CKD and DKD in residents of Central China. The high prevalence suggests an urgent need to implement interventions to relieve the high burden of CKD and DKD in China.


Asunto(s)
Nefropatías Diabéticas , Insuficiencia Renal Crónica , China/epidemiología , Creatinina/análisis , Estudios Transversales , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/diagnóstico , Nefropatías Diabéticas/epidemiología , Femenino , Tasa de Filtración Glomerular , Humanos , Pruebas de Función Renal/métodos , Pruebas de Función Renal/estadística & datos numéricos , Estilo de Vida , Masculino , Anamnesis/estadística & datos numéricos , Persona de Mediana Edad , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Medición de Riesgo , Factores de Riesgo , Población Urbana
12.
J Environ Sci (China) ; 91: 117-127, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32172960

RESUMEN

Biological nitrogen removal process could be affected due to the presence of heavy metals owing to their toxicity and accumulation in the sludge. In this study, the impact of Cu2+ shock on a long-term nitritation operation was investigated in an air-lift reactor with self-recirculation. Both the dynamics of microbial community and inhibition kinetics under Cu2+ stress were ascertained. The results showed that Cu2+ exerted severe inhibition on nitritation performance of an air-lift reactor (ALR) at 25 mg/L. The corresponding NH4+-N removal efficiency decreased to below 50%, which was mainly due to the variation of microbial community structure, especially the inhibition of nitrifiers like Nitrosomonas (the relative abundance decreased from 30% to 1% after Cu2+ inhibition). Kinetic parameters were obtained and compared after fitting the Haldane model. The long-term Cu2+ stress on the ALR aggravated the ammonium affinity and the resistance to substrate self-inhibition of the nitritation sludge, but reduced the resistance to Cu2+ inhibition. Furthermore, Cu2+ acted as uncompetitive inhibitor on nitritation process. Our results provide new insights into the nitritation characteristics under long-term Cu2+ stress.


Asunto(s)
Compuestos de Amonio , Microbiota , Reactores Biológicos , Cinética , Nitrógeno , Oxidación-Reducción , Aguas del Alcantarillado
13.
Environ Sci Technol ; 53(1): 342-353, 2019 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-30500178

RESUMEN

The role of soluble microbial products (SMP), the most important component of effluent organic matter from municipal wastewater treatment plants, in sulfate radical (SO4•-)-based advanced oxidation technologies (AOTs) remains substantially unclear. In this study, we first utilized a suite of macro- and microanalytical techniques to characterize the SMP from a membrane bioreactor for its fundamental molecular, spectroscopic, and reactivity properties. The degradation kinetics of three representative pharmaceuticals (i.e., naproxen, gemfibrozil, and sulfadiazine) in the presence of SMP was significantly reduced as compared to in its absence. Possible mechanisms for the interference by SMP in degrading these target compounds (TCs) were investigated. The low percentage of bound TCs to SMP ruled out the cage effect. The measurement of steady-state 1O2 concentration indicated that formation of 1O2 upon UV irradiation on SMP was not primarily responsible for the degradation of TCs. However, the comparative and quenching results reveal that SMP absorbs UV light acting as an inner filter toward the TCs, and meanwhile scavenges SO4•- with a high second-order rate constant of 2.48 × 108 MC-1 s-1.


Asunto(s)
Sulfatos , Aguas Residuales , Reactores Biológicos , Cinética
14.
J Environ Manage ; 215: 248-257, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29573675

RESUMEN

The stability and resilience of an anaerobic ammonium oxidation (anammox) system under transient nanoscale Zero-Valent Iron (nZVI) (50, 75 and 100 mg L-1), hydraulic shock (2-fold increase in flow rate) and their combination were studied in an up-flow anaerobic sludge blanket reactor. The response to the shock loads can be divided into three phases i.e. shock, inertial and recovery periods. The effects of the shock loads were directly proportional to the shock intensity. The effluent quality was gradually deteriorated after exposure to high nZVI level (100 mg L-1) for 2 h. The higher effluent sensitivity index and response caused by unit intensity of shock was observed under hydraulic and combined shocks. Notably, the specific anammox activity and the content of heme c were considerably reduced during the shock phase and the maximum loss rates were about 30.5% and 24.8%, respectively. Nevertheless, the extracellular polymeric substance amount in the shock phase was enhanced in varying degrees and variation tendency was disparate at all the tested shock loads. These results suggested that robustness of the anammox system was dependent on the magnitude shocks applied and the reactor resistance can be improved by reducing hydraulic retention time with the increase of nZVI concentration under these circumstances.


Asunto(s)
Hierro/química , Aguas Residuales , Reactores Biológicos , Aguas del Alcantarillado , Purificación del Agua
15.
PLoS Genet ; 9(11): e1003791, 2013 11.
Artículo en Inglés | MEDLINE | ID: mdl-24244175

RESUMEN

In most mouse tissues, long-interspersed elements-1 (L1s) are silenced via methylation of their 5'-untranslated regions (5'-UTR). A gradual loss-of-methylation in pre-implantation embryos coincides with L1 retrotransposition in blastocysts, generating potentially harmful mutations. Here, we show that Dicer- and Ago2-dependent RNAi restricts L1 accumulation and retrotransposition in undifferentiated mouse embryonic stem cells (mESCs), derived from blastocysts. RNAi correlates with production of Dicer-dependent 22-nt small RNAs mapping to overlapping sense/antisense transcripts produced from the L1 5'-UTR. However, RNA-surveillance pathways simultaneously degrade these transcripts and, consequently, confound the anti-L1 RNAi response. In Dicer(-/-) mESC complementation experiments involving ectopic Dicer expression, L1 silencing was rescued in cells in which microRNAs remained strongly depleted. Furthermore, these cells proliferated and differentiated normally, unlike their non-complemented counterparts. These results shed new light on L1 biology, uncover defensive, in addition to regulatory roles for RNAi, and raise questions on the differentiation defects of Dicer(-/-) mESCs.


Asunto(s)
Proteínas Argonautas/genética , ARN Helicasas DEAD-box/genética , Células Madre Embrionarias/metabolismo , Elementos de Nucleótido Esparcido Largo/genética , Interferencia de ARN , Ribonucleasa III/genética , Regiones no Traducidas 5' , Animales , Diferenciación Celular/genética , Proliferación Celular , ARN Helicasas DEAD-box/metabolismo , Metilación de ADN/genética , Regulación del Desarrollo de la Expresión Génica , Ratones , Regiones Promotoras Genéticas , Retroelementos/genética , Ribonucleasa III/metabolismo
16.
Biodegradation ; 27(2-3): 131-44, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27091324

RESUMEN

The short-cut nitrification (SCN) performance of an airlift reactor (ALR) was investigated under increasing bicarbonate condition. The sequential increase of bicarbonate from 2.5 to 7.0 g/L accelerated the nitrite accumulation and improved the NAP to 99 %. With the increase of bicarbonate dose to 11 g/L, the ammonium removal efficiency and the ammonium removal rate (ARR) were improved to 95.1 % and 0.57 kg/m(3)/day, respectively. However, the elevation of bicarbonate concentration from 11.0 to 14.0 g/L gradually depreciated the nitrite accumulation percentage to 62.5 %. Then, the reactor was operated in increasing ammonium strategy to increase the nitrogen loading rate (NLR) to 1.1 kg/m(3)/day under 700 mg/L influent ammonium concentration. The ARR and nitrite production rate were elevated to 1.1 and 0.9 kg/m(3)/day, respectively. The SCN performance was improved to 1.8 kg/m(3)/day (NLR) by the subsequent progressive shortening of HRT to 4.8 h at ammonium concentration of 350 mg/L, which was 1.6 times higher than that of the increasing ammonium strategy. Chemical analysis with EDS, FTIR and XRD confirmed the presence of CaCO3 precipitates on biomass surface during the long-term operation under high bicarbonate conditions. The attachment of precipitates to the SCN sludge helped to improve the biomass settleability and finally enhanced the SCN performance of the ALR.


Asunto(s)
Bicarbonatos/química , Biomasa , Reactores Biológicos , Carbonato de Calcio/química , Nitrificación , Compuestos de Amonio/metabolismo , Biodegradación Ambiental , Eliminación de Residuos Líquidos
17.
Biomed Environ Sci ; 29(11): 814-817, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27998387

RESUMEN

This cohort study was designed to evaluate the association of transcription factor 7-like 2 (TCF7L2) and proglucagon gene (GCG) variants with disordered glucose metabolism and the incidence of type 2 diabetes mellitus (T2DM) in a rural adult Chinese population. A total of 7,751 non-T2DM participants ⋝18 years old genotyped at baseline were recruited. The same questionnaire interview and physical and blood biochemical examinations were performed at both baseline and follow-up. During a median 6 years of follow-up, T2DM developed in 227 participants. After adjustment for potential contributory factors, nominally significant associations were seen between TT genotype and the recessive model of TCF7L2 rs7903146 and increased risk of T2DM [hazard ratio (HR)=4.068, 95% confidence interval (CI): 1.270-13.026; HR=4.051, 95% CI: 1.268-12.946, respectively]. The TT genotype of rs7903146 was also significantly associated with higher fasting plasma insulin level and the homeostasis model assessment of insulin resistance in case of new-onset diabetes. In addition, the TCF7L2 rs290487 TT genotype was associated with abdominal obesity and the GCG rs12104705 CC genotype was associated with both general obesity and abdominal obesity in case of new-onset diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Resistencia a la Insulina/genética , Obesidad/genética , Proglucagón/genética , Proteína 2 Similar al Factor de Transcripción 7/genética , Adulto , Estudios de Cohortes , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Insulina/metabolismo , Secreción de Insulina , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Polimorfismo de Nucleótido Simple
18.
J Environ Manage ; 181: 756-761, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27449964

RESUMEN

Wastewater treatment sludge from a primary lead-zinc smelter is characterized as hazardous waste and requires treatment prior to disposal due to its significant arsenic and heavy metals contents. This study presents a method for the stabilization of arsenic sludge that uses a slag based curing agent composed of smelting slag, cement clinker and limestone. The Unconfined Compressive Strength (UCS) test, the China Standard Leaching Test (CSLT), and the Toxicity Characteristic Leaching Procedures (TCLP) were used to physically and chemically characterize the solidified sludge. The binder ratio was determined according to the UCS and optimal experiments, and the optimal mass ratio of m (smelting slag): m (cement clinker): m (gypsum sludge): m (limestone) was 70:13:12:5. When the binder was mixed with arsenic sludge using a mass ratio of 1:1 and then maintained at 25 °C for 28 d, the UCS reached 9.30 MPa. The results indicated that the leached arsenic content was always less than 5 mg/L, which is a safe level, and does not contribute to recontamination of the environment. The arsenic sludge from the Zn/Pb metallurgy plant can be blended with cement clinker and smelting slag materials for manufacturing bricks and can be recycled as construction materials.


Asunto(s)
Arsénico/química , Restauración y Remediación Ambiental/métodos , Residuos Peligrosos , Metalurgia , Metales Pesados/química , Aguas del Alcantarillado/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Arsénico/análisis , China , Materiales de Construcción , Residuos Industriales/análisis , Plomo/química , Reciclaje , Contaminantes Químicos del Agua/análisis , Zinc/química
19.
Biochem Biophys Res Commun ; 444(1): 86-91, 2014 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-24434141

RESUMEN

Transcriptome studies have revealed that many non-coding RNAs (ncRNAs) are located near the 3' sense terminus of protein-coding genes. However, the transcription and function of these RNAs remain elusive. Here, we identify a 3' sense termini-associated sRNA (TASR) downstream of rpl26 in Schizosaccharomyces pombe (S. pombe). Structure and function assays indicate that the TASR is an H/ACA box snoRNA required for 18S rRNA pseudouridylation at U121 and U305 sites and is therefore a cognate of snR49 from the budding yeast. Transcriptional studies show that pre-snR49 overlaps most of the coding sequence (CDS) of rpl26. Using scanning deletion analysis within promoter region, we show that the rpl26 promoter is required for the 3' TASR transcription. Interestingly, chromosomal synteny of rpl26-snR49 is found in the Schizosaccharomyces groups. Taken together, we have revealed a new transcriptional mechanism for 3' sense TASRs, which are transcribed by the same promoter as their upstream protein genes. These results further suggest that the origin and function of 3' sense ncRNAs are associated with upstream genes in higher eukaryotes.


Asunto(s)
ARN de Hongos/genética , ARN no Traducido/genética , Proteínas Ribosómicas/genética , Proteínas de Schizosaccharomyces pombe/genética , Regiones no Traducidas 3' , Secuencia de Bases , Genes Fúngicos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Homología de Secuencia de Ácido Nucleico , Sintenía , Transcripción Genética
20.
Methods ; 63(1): 76-84, 2013 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-23684746

RESUMEN

It has been shown in small RNA sequencing-based studies that some small RNA fragments are specifically processed from known structural non-coding RNAs, either through Dicer-dependent or Dicer-independent pathways. Although these small RNAs are often less abundant compared to microRNAs in normal mammalian tissues, they are always present in all sequenced libraries. In this paper, we use the ncPRO-seq pipeline, to describe different profiles of these small RNA fragments, and to discuss their potential processing pathways and functions. To assess whether more small RNA fragments can be detected in small RNA sequencing datasets, we decided to focus on small nuclear RNAs, abbreviated as snRNAs, which are associated with Sm ribonucleoproteins to form functional RNA-protein complexes. Here, we describe a group of small RNA fragments derived from snRNAs, which are typically highly enriched in regions bound by Sm proteins. Based on this, we propose the existence of a potential novel small RNA family associated with Sm proteins.


Asunto(s)
ARN Nuclear Pequeño/genética , ARN no Traducido/aislamiento & purificación , Ribonucleoproteínas/genética , Análisis de Secuencia de ARN , Animales , ARN Helicasas DEAD-box/genética , Humanos , Mamíferos , Procesamiento Postranscripcional del ARN , ARN Nuclear Pequeño/metabolismo , ARN no Traducido/genética , Ribonucleasa III/genética , Ribonucleoproteínas/química
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