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1.
BMC Musculoskelet Disord ; 25(1): 40, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191314

RESUMO

OBJECTIVE: This study evaluated the association between admission MCV and preoperative deep vein thrombosis (DVT) in geriatric hip fractures. METHODS: Older adult patients with hip fractures were screened between January 2015 and September 2019. The demographic and clinical characteristics of the patients were collected at the largest trauma center in northwest China. MCV was measured at admission and converted into a categorical variable according to the quartile. Multivariate binary logistic regression and generalized additive model were used to identify the linear and nonlinear association between MCV and preoperative DVT. Analyses were performed using EmpowerStats and the R software. RESULTS: A total of 1840 patients who met the criteria were finally enrolled and divided into four groups according to their MCV levels. The mean MCV was 93.82 ± 6.49 (80.96 to 105.91 fL), and 587 patients (31.9%) were diagnosed with preoperative DVT. When MCV was a continuous variable, the incidence of preoperative DVT increased with mean corpuscular volume. In the fully adjusted model, admission MCV was positively correlated with the incidence of preoperative DVT (OR: 1.03; 95% CI: 1.01-1.05; P = 0.0013). After excluding the effect of other factors, each additional 1fL of MCV increased the prevalence of preoperative DVT by 1.03 times as a continuous variable. CONCLUSION: MCV was linearly associated with preoperative DVT in geriatric patients with hip fractures and could be considered a predictor of DVT risk. The MCV may contribute to risk assessment and preventing adverse outcomes in the elderly. STUDY REGISTRATION: This study is registered on the website of the Chinese Clinical Trial Registry (ChiCTR: ChiCTR2200057323).


Assuntos
Fraturas do Quadril , Trombose Venosa , Idoso , Humanos , Índices de Eritrócitos , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/cirurgia , Estudos Retrospectivos , Trombose Venosa/epidemiologia
2.
Phys Rev Lett ; 130(8): 086701, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36898102

RESUMO

Conventional approaches for lattice dynamics based on static interatomic forces do not fully account for the effects of time-reversal-symmetry breaking in magnetic systems. Recent approaches to rectify this involve incorporating the first-order change in forces with atomic velocities under the assumption of adiabatic separation of electronic and nuclear degrees of freedom. In this Letter, we develop a first-principles method to calculate this velocity-force coupling in extended solids and show via the example of ferromagnetic CrI_{3} that, due to the slow dynamics of the spins in the system, the assumption of adiabatic separation can result in large errors for splittings of zone-center chiral modes. We demonstrate that an accurate description of the lattice dynamics requires treating magnons and phonons on the same footing.

3.
BMC Med Educ ; 23(1): 664, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710261

RESUMO

BACKGROUND: Simulation is an increasingly used novel method for the education of medical professionals. This study aimed to systematically review the efficacy of high-fidelity (HF) simulation compared with low-fidelity (LF) simulation or no simulation in advanced life support (ALS) training. METHODS: A comprehensive search of the PubMed, Chinese Biomedicine Database, Embase, CENTRAL, ISI, and China Knowledge Resource Integrated Database was performed to identify randomized controlled trials (RCTs) that evaluated the use of HF simulation in ALS training. Quality assessment was based on the Cochrane Handbook for Systematic Reviews of Interventions version 5.0.1. The primary outcome was the improvement of knowledge and skill performance. The secondary outcomes included the participants' confidence and satisfaction at the course conclusion, skill performance at one year, skill performance in actual resuscitation, and patient outcomes. Data were synthesized using the RevMan 5.4 software. RESULTS: Altogether, 25 RCTs with a total of 1,987 trainees were included in the meta-analysis. In the intervention group, 998 participants used HF manikins, whereas 989 participants received LF simulation-based or traditional training (classical training without simulation). Pooled data from the RCTs demonstrated a benefit in improvement of knowledge [standardized mean difference (SMD) = 0.38; 95% confidence interval (CI): 0.18-0.59, P = 0.0003, I2 = 70%] and skill performance (SMD = 0.63; 95% CI: 0.21-1.04, P = 0.003, I2 = 92%) for HF simulation when compared with LF simulation and traditional training. The subgroup analysis revealed a greater benefit in knowledge with HF simulation compared with traditional training at the course conclusion (SMD = 0.51; 95% CI: 0.20-0.83, P = 0.003, I2 = 61%). Studies measuring knowledge at three months, skill performance at one year, teamwork behaviors, participants' satisfaction and confidence demonstrated no significant benefit for HF simulation. CONCLUSIONS: Learners using HF simulation more significantly benefited from the ALS training in terms of knowledge and skill performance at the course conclusion. However, further research is necessary to enhance long-term retention of knowledge and skill in actual resuscitation and patient's outcomes.


Assuntos
Treinamento com Simulação de Alta Fidelidade , Humanos , Simulação por Computador , Escolaridade , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Nano Lett ; 22(6): 2244-2250, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35274532

RESUMO

Single photon emitters (SPEs) are critical components of photon-based quantum technology. Recently, the interaction between surface plasmons and emitters has attracted increasing attention because of its potential to improve the quality of single-photon sources through stronger light-matter interactions. In this work, we use a hybrid plasmonic probe composed of a fiber taper and silver nanowire to controllably modulate the radiation properties of SPEs with differently oriented polarization. For out-of-plane oriented SPEs such as single CdSe quantum dots, the radiation lifetime could be reduced by a factor as large as seven; for in-plane oriented SPEs such as hBN defect SPEs, the average modulation amplitude varied from 0.69 to 1.23, depending on the position of the probe. The experimental results were highly consistent with the simulations and theory. This work provides an efficient approach for optimizing the properties of SPEs for quantum photonic integration.

5.
Environ Sci Technol ; 56(2): 1310-1320, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34941249

RESUMO

An innovative partial nitrification, in situ fermentation, and Anammox (PNFA) system was developed to achieve mature landfill leachate and waste activated sludge simultaneous treatment. Three separate sequencing batch reactors (SBRs) were used for partial nitrification (PN-SBR), integrated fermentation-denitrification (IFD-SBR), and partial nitrification-Anammox (PNA-SBR). After 200 days of continuous operation, a satisfactory nitrogen removal efficiency (NRE) of 99.2 ± 0.1% was obtained, with an effluent total nitrogen (TN) of 15.2 ± 3.2 mg/L. In IFD-SBR, the volatile fatty acids generated from fermentation drove efficient denitrification, obtaining sludge and nitrogen reduction rates of 4.2 ± 0.7 and 0.61 ± 0.04 kg/m3·day, respectively. Furthermore, unwanted fermentation metabolites (134.1 mg/L NH4+-N) were further treated by PNA-SBR using a combination of step-feed and intermittent aeration strategies. In PNA-SBR, Anammox significantly contributed to 82.1% nitrogen removal, and Anammox bacteria (Candidatus Brocadia, 2.3%) mutually benefited with partially denitrifying microorganisms (Thauera, 4.2%), with 66.3% of generated nitrate reduced to nitrite and then reutilized in situ by Anammox. Compared with the conventional nitrification-denitrification process, PNFA reduced oxygen energy consumption, external carbon source dosage, and CO2 emission by 21.3, 100, and 38.9%, respectively, and obtained 50.1% external WAS reduction efficiency.


Assuntos
Nitrificação , Poluentes Químicos da Água , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Desnitrificação , Fermentação , Nitrogênio , Oxirredução , Esgotos , Águas Residuárias
6.
Anal Chem ; 93(9): 4317-4325, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33620193

RESUMO

Poor antimatrix interference capability of aptamers is one of the major obstacles preventing their wide applications for real-sample detections. Here, we devise a multiple-function interface, denoted as a nanoscale affinity double layer (NADL), to overcome this bottleneck via in situ simultaneous target enrichment, purification, and detection. The NADL consists of an upper aptamer layer for target purification and sensing and a lower nanoscale solid-phase microextraction (SPME) layer for sample enrichment. The targets flowing through the NADL-functionalized surface are instantly million-fold enriched and purified by the sequential extraction of aptamer and SPME. The formation of the aptamer-target complex is greatly enhanced, enabling ultrasensitive detection of targets with minimized interference from the matrix. Taking the fiber-optic evanescent wave sensor as an example, we demonstrated the feasibility and generality of the NADL. The unprecedented detection of limits of 800, 4.8, 40, and 0.14 fM were, respectively, achieved for three representative small-molecule targets with distinct hydrophobicity (kanamycin A, sulfadimethoxine, and di-(2-ethylhexyl) phthalate) and protein target (human serum albumin), corresponding to 2500 to 3 × 108-fold improvement compared to the sensors without the NADL. Our sensors also showed exceptionally high target specificity (>1000) and tunable dynamic ranges simply by manipulating the SPME layer. With these features comes the ability to directly detect targets in diluted environmental, food, and biological samples at concentrations all well below the tolerance limits.

7.
Zhonghua Nan Ke Xue ; 27(10): 892-898, 2021 10 20.
Artigo em Zh | MEDLINE | ID: mdl-34914267

RESUMO

Objective: To assess the feasibility and validity of the establishment of a modified channel for extraperitoneal robot-assisted laparoscopic radical prostatectomy (RARP) through single incision. METHODS: From November 2020 to January 2021, 35 cases of localized PCa were treated by extraperitoneal RARP through single incision in our center. All the operations were performed by the same surgeon, none via the multichannel port for the establishment of the channel. We recorded and analyzed the intra- and postoperative parameters, operation cost, complications, pathological findings and follow-up data. RESULTS: All the operations were successfully completed, without conversion to open surgery or additional channels, or serious postoperative complications, the time for establishing the extraperitoneal space averaging 25.4 (20.0-45.0) min, the operation time 67.3 (35.0-125.0) min, intraoperative blood loss 75.5 (60.0-150.0) ml, time to first postoperative anal exhaust 26 (8-48) h, and postoperative hospital stay 7.89 (7-10) d. Postoperative pathology showed adenocarcinoma in all the cases, with Gleason score (GS) 3+3 in 9 (25.7%), GS 3+4 in 9 (25.7%), GS 4+3 in 8 (22.9%), and GS ≥ 8 in 9 (25.7%) of the cases, 23 (65.7%) in the

Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Perda Sanguínea Cirúrgica , Humanos , Masculino , Prostatectomia
8.
BMC Surg ; 20(1): 186, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32791964

RESUMO

BACKGROUND: Cavernous hemangioma, as a rare tumor, is difficult to differentiate from retroperitoneal lymphoma and paraganglioma. They are more difficult to excise completely through open surgery and traditional laparoscopic surgery. The study aimed to evaluate the role of DaVinci surgical system in laparoscopic resection of parapelvic cavernous hemangioma. CASE PRESENTATION: A 46-year-old female, who diagnosed as parapelvic cavernous hemangioma accompanying with thrombosis and calcification, was performed laparoscopic resection using DaVinci surgical system under general anesthesia. The patient well recovered without recurrence or spread of the lesion after operation for 3 months as well as hydronephrosis was significantly relieved. CONCLUSION: Laparoscopic resection of parapelvic cavernous hemangioma under the help of DaVinci surgical system was feasible and safe.


Assuntos
Hemangioma Cavernoso , Laparoscopia , Neoplasias Pélvicas , Neoplasias Retroperitoneais , Procedimentos Cirúrgicos Robóticos , Feminino , Hemangioma Cavernoso/diagnóstico por imagem , Hemangioma Cavernoso/cirurgia , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Pélvicas/diagnóstico por imagem , Neoplasias Pélvicas/cirurgia , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias Retroperitoneais/cirurgia , Tomografia Computadorizada por Raios X
9.
Soft Matter ; 14(45): 9185-9193, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30398506

RESUMO

We study the crystal nucleation of the Weeks-Chandler-Andersen (WCA) model, using the recently introduced persistent embryo method (PEM). The method provides detailed characterization of pre-critical, critical and post-critical nuclei, as well as nucleation rates that compare favorably with those obtained using other methods (umbrella sampling, forward flux sampling or seeding). We further map our results to a hard sphere model allowing comparison with other existing predictions. Implications for experiments are also discussed.


Assuntos
Cristalização , Modelos Moleculares
10.
J Sep Sci ; 41(3): 740-746, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29152857

RESUMO

Traditional Chinese herbal medicine has long enjoyed the reputation of the world's most advanced system of natural medicine. Pinellia ternata is one of the most commonly used herbs in the traditional Chinese medical science. In this study, five representative ingredients of Pinellia ternata guanosine, methionine, glycine, 3,4-dihydroxybenzaldehyde, and homogentisic acid, were assayed using simple derivatization procedures. Under optimized experimental condition, five analytes in Pinellia ternata were rapidly separated and detected using microchip electrophoresis, affording the benefits of speed, minimal sample requirements, and sensitive on-the-chip electrochemical detection, in 5 min with linearity over a concentration of 20-500 µM (R2  = 0.994) with nearly complete recovery (95.6-98.5%).


Assuntos
Medicamentos de Ervas Chinesas/análise , Eletroforese em Microchip , Pinellia/química , Benzaldeídos/análise , Soluções Tampão , Catecóis/análise , Eletroforese , Glicina/análise , Guanosina/análise , Ácido Homogentísico/análise , Concentração de Íons de Hidrogênio , Modelos Lineares , Metionina/análise , Análise de Sequência com Séries de Oligonucleotídeos
11.
Ren Fail ; 39(1): 299-305, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28050928

RESUMO

To evaluate the association between the SPO11 gene C631T polymorphism and the risk of male infertility. We conducted a search on PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure (CNKI), China biology medical literature database (CBM), VIP, and Chinese literature database (Wan Fang) on 31 March 2016. Odds ratio (OR) and 95% confidence interval (95%CI) were used to assess the strength of associations. A total of five studies including 542 cases and 510 controls were involved in this meta-analysis. The pooled results indicated that the SPO11 gene C631T polymorphism was significantly associated with increased risk of male infertility (TT + CT vs. CC: OR = 4.14, 95%CI = 2.48-6.89; CT vs. CC: OR = 4.34, 95%CI = 2.56-7.34; T vs. C: OR = 4.35, 95%CI = 2.58-7.34). Subgroup analysis of different countries proved the relationship between SPO11 gene C631T polymorphism and male infertility risk in Chinese, but not in Iranian peoples. In conclusion, this study suggested that SPO11 gene C631T polymorphism may contribute as a genetic factor susceptible to cause male infertility. Furthermore, more large sample and representative population-based cases and well-matched controls are needed to validate our results.


Assuntos
Endodesoxirribonucleases/genética , Infertilidade Masculina , Adulto , China/epidemiologia , Predisposição Genética para Doença , Humanos , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/genética , Masculino , Polimorfismo de Nucleotídeo Único , Medição de Risco
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(3): 371-5, 2016 May.
Artigo em Zh | MEDLINE | ID: mdl-27468483

RESUMO

OBJECTIVE: To investigate the clinical outcome of immediate inguinal lymph node dissection on the survival of the patients with penile carcinoma. METHODS: A total of 67 patients of penile carcinoma whose inguinal lymph nodes (ILN) were initial clinically impalpable, received inguinal lymph node dissection (ILND) from Dec 2008 to April 2014. Among them, 33 patients received immediate ILND within 1 month after the resection of penile cancer, while 34 patients underwent delayed ILND which was performed when ILN was found clinically apparent during follow-up. The Kaplan-Meier survival analysis was performed. The prognostic factors was evaluated by log-rank test, including age, morphology, location, T stage, grade of primary tumor, clinical status of ILN before ILND, lymphatic pathology, time to ILND. Cox proportional hazard model was used to find the independent risk factors on survival. RESULTS: The median age was 50 year-old (range 26 to 84 year-old). The median follow-up time was 23 months (range 3-76 months). The 3-year and 5-year overall survival were 70.1% and 65.4%, respectively, The 5-year survival rate in immediate ILND and delayed ILND group were 93.1%, and 33.7% respectively. Positive ILN metastasis was found in 7 patients from immediate ILND group but 26 patients from delayed ILND group that the prognostic factors included T stage, tumor grade, clinical status of inguinal lymph nodes before ILND, and lymphatic pathology. Cox model found the status of inguinal lymph nodes was independent prognostic factor for the survival. CONCLUSION: Inguinal lymph node metastasis is the important prognostic indicator of the survival of penile cancer. Immediate ILND could improve survival for the patients with clinically impalpable lymph nodes.


Assuntos
Excisão de Linfonodo , Neoplasias Penianas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Estimativa de Kaplan-Meier , Linfonodos/cirurgia , Metástase Linfática , Vasos Linfáticos , Masculino , Pessoa de Meia-Idade , Neoplasias Penianas/diagnóstico , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Taxa de Sobrevida
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 45(2): 192-5, 201, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-24749338

RESUMO

OBJECTIVE: To study the differentiation of human bone marrow mesenchymal stem cells (BMSCs) into Leydig or steroidogenic cells in vivo and the immunoreaction related to transplantation into mouse testis. METHODS: After differentiation and cultivation, the 3rd-passage BMSCs were collected and labeled with Hoechest 33342, and joined the saline fluorouracil to form cell-suspending fluid. After injection of the etgane dimethane sulphonate (EDS), the mice received the transplanted cell-suspending fluid by testis net injection with a dose of each side testicular 0.05 mL. Since the first day prior to transplantation, mice were executed every 2 d (one mouse each time) and the testosterone concentrations were analyzed. The control group included 20 BALB/c mice without any treatment during the same period. The results were analyzed by microscopic observation, using 3beta-hydroxysteroid dehydrogenase (3beta-HSD) monoclonal antibody and mouse anti-human cell nucleus monoclonal antibody for immunofluorescence assay on the testis. For tracking the BMSCs, the cells which were positively stained with both 3beta-HSD and mouse anti-human cell nucleus monoclonal antibodies were retrieved. RESULTS: Certain killing effect of EDS to the mouse Leydig cells was observed. Transplantation of human BMSCs into the mouse testis by testis net injection was effective and feasible, no immunoreactions were detected. After transplantation, no positive cells of 3beta-HSD) and mouse anti-human cell nucleus monoclonal antibody were found. CONCLUSION: Transplantation of human BMSCs into the mouse testis by testis net injection was effective and feasible, no immunoreactions were detected. After transplantation, the human BMSCs failed to differentiate into Leydig cells or steroidogenic cells.


Assuntos
Diferenciação Celular , Células Intersticiais do Testículo/citologia , Células-Tronco Mesenquimais/citologia , Testículo/citologia , Animais , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais , Camundongos , Camundongos Endogâmicos BALB C , Testosterona/análise
14.
Cureus ; 15(9): e45398, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37854739

RESUMO

Objective This study evaluated the association between N-terminal prohormone of brain natriuretic peptide (NT-proBNP) concentration and one-year mortality in geriatric patients with intertrochanteric and femoral neck fractures receiving the operative treatment. Methods Consecutive age ≥65 years patients with hip fractures were screened between January 2015 and September 2019. Demographic and clinical characteristics of the patients were collected. The multivariate logistic regression models were used to identify the association between preoperative NT-proBNP concentrations and mortality. All analyses were performed using EmpowerStats and the R software. Result One thousand two hundred nineteen patients were included in the study. The average age was 79.73±6.65 years (range 66-99 years). The mean NT-proBNP concentration was 616.09±1086.85 ng/L (median 313.40 ng/L, range 16.09-20123.00 ng/L). The follow-up was 35.39±15.09 months (median 35.78 months, range 0.10-80.14 months). One hundred and eleven (9.1%) patients died within one year. After adjusting for confounding factors, multivariate logistic regression models showed a curved association between preoperative NT-proBNP concentration and one-year mortality. When the NT-proBNP concentration was below 1099 ng/L, the mortality increased by 10% (OR=1.10, 95%CI: 1.03-1.17, P=0.0025) when NT-proBNP increased by 100 ng/L. When the NT-proBNP concentration was above 1099 ng/L, the mortality did not increase anymore when NT-proBNP increased (OR=1.00, 95%CI: 0.99-1.02, P=0. 7786). Thus, NT-proBNP was a valuable indicator to predict high one-year mortality in practice. Conclusion The NT-proBNP concentrations were nonlinearly associated with mortality in elderly hip fractures with a saturation effect, and NT-proBNP was a risk indicator of all-cause mortality. A well-designed controlled trial to show the role of mortality by decreasing the concentration of NT-proBNP is needed in the future.

15.
Bioresour Technol ; 387: 129573, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37506937

RESUMO

The biological treatment system for high-strength wastewater, particularly landfill leachate, typically requires high sludge concentration to maintain nitrogen removal performance. However, it frequently causes an excessive accumulation of toxins in microbial metabolism, resulting in unstable performance during long-term operation. An efficient two-stage partial nitrification/anammox (PN/A) mature landfill leachate process with low sludge concentration was constructed by settling time reduction and Ca2+ addition. The ammonia removal rate reached 46.7 mg N/(L·h) in PN-SBR. Nitrosomonas (2.0%) was the sole genus responsible for partial nitrification. The influent NO2--N/NH4+-N of A-SBR was kept at 1.39, leading to a dynamic equilibrium of anammox and denitrification. Ca. Brocadia recovered fastest (0.32% â†’ 1.8%) among the detected AnAOB genera. The process achieved NRE of 95.0% with effluent TIN of 37.6 mg/L (<40 mg/L). This research offered recommendations for the favorable operation of the two-stage PN/A mature landfill leachate treatment system with low sludge concentration.


Assuntos
Nitrificação , Poluentes Químicos da Água , Desnitrificação , Esgotos , Nitrogênio , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Oxirredução
16.
Biosensors (Basel) ; 12(7)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35884240

RESUMO

Zearalenone (ZEN) is a common mycotoxin pollutant found in agricultural products. Aptamers are attractive recognition biomolecules for the development of mycotoxin biosensors. Even though numerous aptasensors have been reported for the detection of ZEN in recent years, many of them suffer from problems including low sensitivity, low specificity, tedious experimental steps, high-cost, and difficulty of automation. We report here the first evanescent wave optical-fiber aptasensor for the detection of ZEN with unprecedented sensitivity, high specificity, low cost, and easy of automation. In our aptasensor, a 40-nt ZEN-specific aptamer (8Z31) is covalently immobilized on the fiber. The 17-nt fluorophore Cy5.5-labeled complementary DNA strand and ZEN competitively bind with the aptamer immobilized on the fiber, enabling the signal-off fluorescent detection of ZEN. The coating of Tween 80 enhanced both the sensitivity and the reproducibility of the aptasensor. The sensor was able to detect ZEN spiked-in the corn flour extract with a semilog linear detection range of 10 pM-10 nM and a limit of detection (LOD, S/N = 3) of 18.4 ± 4.0 pM (equivalent to 29.3 ± 6.4 ng/kg). The LOD is more than 1000-fold lower than the maximum ZEN residue limits set by China (60 µg/kg) and EU (20 µg/kg). The sensor also has extremely high specificity and showed negligible cross-reactivity to other common mycotoxins. In addition, the sensor was able to be regenerated for 28 times, further decreasing its cost. Our sensor holds great potential for practical applications according to its multiple compelling features.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Micotoxinas , Zearalenona , Aptâmeros de Nucleotídeos/química , Limite de Detecção , Micotoxinas/análise , Reprodutibilidade dos Testes , Zea mays , Zearalenona/análise
17.
Biosens Bioelectron ; 196: 113702, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34655971

RESUMO

Alternariol (AOH) is one of the common mycotoxins existing in a variety of foods at low level. Aptamers hold great promise for the development of sensitive and rapid aptasensors, but suffer from the excessive length and the difficulty in identification of critical binding domains (CBDs). In this study, the 5 nt CBD of the original 59-nt AOH aptamer (AOH-59, KD = 423 nM) was identified to be a 'C' bulge in between two A-T base pairs. AOH-59 was successfully shortened to a 23 nt aptamer (AOH 6C, KD = 701 nM). A 30 nt bivalent aptamer B-2-3 (KD = 445 nM) and a 39 nt trivalent aptamer T-2-3 (KD = 274 nM) were obtained by simply incorporating one or two CBDs into AOH 6C. The AOH 6C-, B-2-3-, and T-2-3-based optical waveguide aptasensors possessed the unprecedented detection of limits (LODs, S/N = 3) of 42 ± 3, 6 ± 1 and 2 ± 1 fM, respectively. Using the AOH 6C-based sensor as an example, we further demonstrated the detection of AOH spiked in wheat powder with a LOD of 37 pg/g, 20-230-fold lower than those achieved by ELISAs. The sensor was capable for 35 times 2-min regeneration and the assay time including the extraction of AOH from wheat was only about 1 h. We not only devised the first aptasensors for AOH detection, but also provided a simple strategy to design multivalent aptamers for small molecule targets.


Assuntos
Técnicas Biossensoriais , Micotoxinas , Lactonas , Triticum
18.
Bioresour Technol ; 347: 126676, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34999191

RESUMO

A continuous plug-flow multistage anoxic/oxic (A/O) system based on one-stage partial nitrification coupled anammox (PNA) process with integrated fixed-film activated sludge (IFAS) was established and operated over 400 days. A step feed strategy effectively controlled free ammonia concentration and alleviated impacts on ammonia oxidizing bacteria (AOB) and anammox bacteria (AnAOB). During day 301-405, 98.1% of total inorganic nitrogen was removed from mature landfill leachate, whereas chemical oxygen demand (COD) removal efficiency was 52.9%. With the enrichment of AnAOB in oxic biofilm, nitrogen removal via the anammox pathway reached 94.3%-95.0%. During system operation, the dominant anammox genus shifted from Candidatus_Brocadia to Candidatus_Kuenenia. Fluorescent in situ hybridization (FISH) indicated AnAOB encapsulated by AOB colonies were mainly distributed inside of the biofilm, which promoted nitrite utilization by the anammox process. This innovative system and the results are of great value to practical applications.


Assuntos
Nitrogênio , Poluentes Químicos da Água , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Desnitrificação , Hibridização in Situ Fluorescente , Nitrificação , Oxirredução , Esgotos
19.
Bioresour Technol ; 363: 127865, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36049709

RESUMO

This study established the one-stage partial nitrification coupled anammox and partial denitrification coupled anammox process in an anoxic/oxic continuous plug-flow system and operated for 465 days to treat mature landfill leachate. 97.9 %-98.1 % of inorganic nitrogen was removed when the nitrogen loading rate was maintained at 0.33-0.36 kg N/m3/d, and a high anammox contribution to nitrogen removal (89.8 %-92.4 %) was achieved. The long-term in-situ free ammonia (FA) anoxic treatment contributed to the stable performances of partial nitrification and in-situ fermentation. The employed integrated fixed-film activated sludge technology favored the enrichment of hzsA, hzsB, hdh, amoA, hao, narG, and napA functional genes. The oxic zone, particularly oxic biofilm, was the key zone for anammox pathway, where Candidatus_Kuenenia (from 1.6 % to 8.3 %) with high tolerance to FA and salinity stress outcompeted Candidatus_Brocadia (from 18.3 % to 0.1 %) as the dominant anammox bacteria. This study could provide guidance for anammox-mediated landfill leachate treatment in practical projects.


Assuntos
Desnitrificação , Poluentes Químicos da Água , Amônia/metabolismo , Oxidação Anaeróbia da Amônia , Reatores Biológicos/microbiologia , Nitrificação , Nitrogênio/metabolismo , Oxirredução , Esgotos
20.
Bioresour Technol ; 361: 127715, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35917860

RESUMO

Municipal solid waste (MSW) leachate treatment through the anaerobic ammonium oxidation (anammox) process has received increasing attention due to less oxygen consumption, carbon source demand, and sludge production. The recent advances in anammox-mediated MSW leachate treatment are systematically reviewed. During MSW leachate treatment, the anammox technology could be flexibly combined with partial nitrification, partial denitrification, fermentation, and methane oxidation. Additionally, this review comprehensively discussed the specific effects on anammox bacteria (AnAOB) of key stressors in MSW leachate such as dissolved organic matters, salinity, and antibiotics, and introduced the corresponding pretreatment methods. The key control strategies focusing on achieving effective AnAOB retention, amelioration of microenvironments, and stable nitrite source were summarized. Moreover, the potential for nitrous oxide emission mitigation in anammox-based MSW leachate treatment systems was evaluated. Finally, this review highlighted the full-scale applications of anammox-mediated MSW leachate treatment and proposed the prospects as well as research gaps in this field.


Assuntos
Desnitrificação , Poluentes Químicos da Água , Oxidação Anaeróbia da Amônia , Reatores Biológicos/microbiologia , Nitrificação , Nitrogênio , Oxirredução , Esgotos , Resíduos Sólidos , Águas Residuárias
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