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During mitosis, kinetochore-microtubule attachments are monitored by a molecular surveillance system known as the spindle assembly checkpoint. The prevailing model posits that dynein evicts checkpoint proteins (e.g., Mad1, Mad2) from stably attached kinetochores by transporting them away from kinetochores, thus contributing to checkpoint silencing. However, the mechanism by which dynein performs this function, and its precise role in checkpoint silencing remain unresolved. Here, we find that dynein's role in checkpoint silencing is restricted to evicting checkpoint effectors from the fibrous corona, and not the outer kinetochore. Dynein evicts these molecules from the corona in a manner that does not require stable, end-on microtubule attachments. Thus, by disassembling the corona through indiscriminate microtubule encounters, dynein primes the checkpoint signaling apparatus so it can respond to stable end-on microtubule attachments and permit cells to progress through mitosis. Accordingly, we find that dynein function in checkpoint silencing becomes largely dispensable in cells in which checkpoint effectors are excluded from the corona.

Antibodies are indispensable tools used for a large number of applications in both foundational and translational bioscience research; however, there are drawbacks to using traditional antibodies generated in animals. These include a lack of standardization leading to problems with reproducibility, high costs of antibodies purchased from commercial sources, and ethical concerns regarding the large number of animals used to generate antibodies. To address these issues, we have developed practical methodologies and tools for generating low-cost, high-yield preparations of recombinant monoclonal antibodies and antibody fragments directed to protein epitopes from primary sequences. We describe these methods here, as well as approaches to diversify monoclonal antibodies, including customization of antibody species specificity, generation of genetically encoded small antibody fragments, and conversion of single chain antibody fragments (e.g. scFv) into full-length, bivalent antibodies. This study focuses on antibodies directed to epitopes important for mitosis and kinetochore function; however, the methods and reagents described here are applicable to antibodies and antibody fragments for use in any field., Competing Interests: KD, JM, AI, WL, LS, KS, SA, NZ, TS, DV, JN No competing interests declared, JD Reviewing editor, eLife, (© 2021, DeLuca et al.)

Waste of Mytella falcata shell was used as low-cost adsorbent to remove the biocide Basic Green 4 (BG4) from water. Shells were collected form trash nearby the lagoon were Mytella falcata is fished. After clean, dry and crushed, the powder was characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), and X-ray dispersive energy spectroscopy (EDS). Both kinetic and equilibrium adsorption tests are carried out. Adsorbent regenerability was tested during adsorption/desorption cycles, using a UV photo-regeneration process. The maximum adsorption capacity reached 539.24 mg.g-1 (60 °C), which was higher than those retrieved for other materials with similar origin. The kinetic results indicated that the process followed pseudo-second order model. Equilibrium data indicate an increase in BG4 adsorption capacity with temperature and Sips model had better fit for all the investigated temperatures (30, 40, 50 and 60 °C). The regeneration/reuse test indicated that the adsorbent is able to assure a BG4 removal above 70 % during five adsorption/desorption cycles evaluated. Thermodynamic parameters suggested that adsorption is spontaneous, endothermal, governed by chemisorption and with structural changes in the solid surface upon adsorption., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The palm (Elaeis guineensis), known as dendê, is an important oleaginous Brazilian plant with a high performance of oil production. In this work, a 2 3 full experimental design was performed and the response surface method (RSM) was used to indicate the optimum parameter of caffeine adsorption on Elaeis guineensis endocarp activated carbon, since the endocarp is the main by-product from dendê oil production. It was set the adsorbent point of zero charge (pH pzc ), and the material was characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The RSM results indicate removal efficiency (%) at the optimal conditions, 0.20 g of adsorbent, and caffeine initial concentration of 20 mg/L, and acidic medium was about 95%. Based on ANOVA and F test (F calculated > F standard ), the mathematical/statistical model obtained fits well to the experimental data. The overall kinetic studies showed time was achieved after 5 h and caffeine adsorption followed the pseudo-second-order model suggesting chemisorption is a predominant mechanism. Redlich-Peterson and Sips models best represented the experimental data (0.967 < R 2 < 0.993). Thermodynamic revealed that caffeine adsorption was spontaneous at all temperatures studied, exothermic, and probably with changes in the adsorbate-adsorbent complex during the process. The tests conducted in different water matrixes corroborate the suitability of this adsorbent to be used in caffeine removal even in a complex solution.

Mg-Fe layered double hydroxide intercalated with chloride (Mg-Fe-Cl LDH) was synthetized, characterized, and evaluated as adsorbent to remove nitrate from aqueous solution. The pH, initial nitrate concentration, adsorbent dosage, and particle size were investigated. Kinetic data was best represented by pseudo-second order model indicating that the rate limiting step was chemisorption. Intraparticle diffusion model indicates that adsorption kinetic is limited by external and intraparticle diffusion. Sips model was selected, based on R 2 , ARE, and AIC, to adequately represent the adsorption isotherms, which permits to affirm that the adsorption occurs in heterogeneous surface, obtaining the maximum adsorption capacity of 18.17 mg.g -1 at 30  o C. Thermodynamics parameters indicate that the adsorption was spontaneous, exothermic, and with structural modification. These findings come up with Mg-Fe-Cl LDH as a suitable adsorbent for nitrate and could contribute to its removal from the water and wastewater.

The endocarp of Wodyetia bifurcata was used to produce biochar by vacuum pyrolysis as an alternative adsorbent for methylene blue (MB) removal. The influence of different pyrolysis temperatures, particle diameters and activation agents in the adsorption process was studied. Kinetics and adsorption equilibrium were also evaluated. Biochar obtained at higher pyrolysis temperatures and activated with H 3 PO 4 showed the best adsorptive capacities, achieving 83% of MB removal. The experimental data fitted better with pseudo-second order model. Isotherms performed at 25, 40, 50 and 60 °C showed that the adsorption of MB onto the activated biochar had no concentration dependence in the range studied. Experimental isotherms fitted well with the Freundlich and Sips models and the thermodynamic parameters suggested a physical adsorption mechanism in a heterogeneous surface, spontaneous at all temperatures evaluated. In brief, the activated carbon obtained from Wodyetia bifurcata can be a promising material for MB removal from aqueous solutions., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In the present work, the composite MgAl-LDH/biochar using activated carbon from bovine bone as support for the layered double hydroxide particles was successfully synthesised and used as an alternative adsorbent for caffeine removal from water. Kinetic studies showed that the equilibrium was achieved in only 20 min of contact between the adsorbent and the adsorbate. The pseudo-first-order model represented the experimental data more satisfactorily (R 2 = 0.95), suggesting a physical adsorption process. The isotherms were performed at three temperatures, in which it was observed the decrease in the adsorption in higher temperatures. It was obtained a maximum adsorption capacity of 26.219 mg/g at 40 °C, and the experimental data were better adjusted by Redlich-Peterson, R 2 > 0.9942. In short, the study demonstrated that the composite was satisfactorily synthesised and its use in the caffeine removal was quite attractive, being a potential adsorbent for water treatment applications.

The present contribution aims to design new-generation bar adsorptive microextraction (BAμE) devices that promote an innovative and much better user-friendly analytical approach. The novel BAμE devices were lab-made prepared having smaller dimensions by using flexible nylon-based supports (7.5 × 1.0 mm) coated with convenient sorbents (≈ 0.5 mg). This novel advance allows effective microextraction and back-extraction ('only single liquid desorption step') stages as well as interfacing enhancement with the instrumental systems dedicated for routine analysis. To evaluate the achievements of these improvements, four antidepressant agents (bupropion, citalopram, amitriptyline and trazodone) were used as model compounds in aqueous media combined with liquid chromatography (LC) systems. By using an N-vinylpyrrolidone based-polymer phase good selectivity and efficiency were obtained. Assays performed on 25 mL spiked aqueous samples, yielded average recoveries in between 67.8 ± 12.4% (bupropion) and 88.3 ± 12.1% (citalopram), under optimized experimental conditions. The analytical performance also showed convenient precision (RSD < 12%) and detection limits (50 ng L -1 ), as well as linear dynamic ranges (160-2000 ng L -1 ) with suitable determination coefficients (r 2  > 0.9820). The application of the proposed analytical approach on biological fluids showed negligible matrix effects by using the standard addition methodology. From the data obtained, the new-generation BAμE devices presented herein provide an innovative and robust analytical cycle, are simple to prepare, cost-effective, user-friendly and compatible with the current LC autosampler systems. Furthermore, the novel devices were designed to be disposable and used together with negligible amounts of organic solvents (100 μL) during back-extraction, in compliance with the green analytical chemistry principles. In short, the new-generation BAμE devices showed to be an eco-user-friendly approach for trace analysis of priority compounds in biological fluids and a versatile alternative over other well-stablished sorption-based microextraction techniques., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A new hybrid microextraction technique (hollow fiber microextraction) is presented that uses the main concepts and advantages of the modern miniaturized devices used for trace analysis. This novel analytical approach uses devices made of polypropylene membranes (10.0 mm long and 0.6 mm internal diameter) in which convenient organic solvents are embedded that promote fast kinetics during the enrichment process, using the floating sampling technology concept. An innovative analytical cycle is also proposed by use of low-cost disposable devices during the microextraction stage together with a user-friendly ("single liquid desorption step") back-extraction stage in compliance with green analytical chemistry principles. To evaluate the performance of the proposed technique, 18 polycyclic aromatic hydrocarbons (PAHs) were used as model compounds and were monitored by gas chromatography coupled with mass spectrometry. Under optimized experimental conditions, assays performed on 25 mL aqueous samples spiked with the PAHs at trace level yielded average recoveries between (14.5 ± 8.2)% (dibenzo[a,h]anthracene) and (90.4 ± 8.4)% (benzo[a]anthracene) with use of a device in which n-nonane had been embedded. Low detection limits were also achieved (2.50-6.00 ng L -1 ), as well as good linear dynamic ranges (20.00-2000.00 ng L -1 ), with suitable coefficients of determination (r 2 > 0.9905) and appropriate precision (relative standard deviation below 15%). By use of the standard addition method, the proposed hybrid microextraction technique had remarkable performance to monitor PAHs at the ultratrace level in several types of matrices, including surface water, wastewater, soil, tea, and fish liver samples. From the data obtained, the new hybrid hollow fiber microextraction technique proved to be user-friendly, eco-friendly, cost-effective, and very competitive for routine work. In short, the novel microextraction technique proposed herein is a remarkable alternative to other well-established microextraction techniques for ultratrace analysis of emerging compounds in real matrices. Graphical abstract Innovative analytical procedure for hollow fiber microextraction (HFμE). GC gas chromatography, LD liquid desorption.

In this study, the enhancement for trace analysis of sulfonamide antibiotics (sulfathiazole, sulfamethoxazole and sulfadimethoxine) and trimethoprim in water matrices is proposed using bar adsorptive microextraction combined with micro-liquid desorption followed by high-performance liquid chromatography with diode array detection (BAμE-μLD/HPLC-DAD). By comparing different polymers and activated carbons as sorbent coatings for BAμE, the polystyrene-divinylbenzene polymer (PS-DVB) showed the best selectivity for the compounds under study. Assays performed through BAμE(PS-DVB)-μLD on 25mL of ultrapure water samples spiked at the 8.0μgL(-1) level showed recoveries ranging from 63.8±1.5% to 84.2±1.9%, under optimized experimental conditions. The validated method provided satisfactory limits of detection (0.08-0.16μgL(-1)) and good linear dynamic ranges (0.16-8.00μgL(-1)) with determination coefficients higher than 0.9958. The proposed analytical methodology was applied to real matrices, such as tap, estuarine and wastewater samples using the standard addition method. It showed to be easy to implement, with good reproducibility, sensitivity and requiring small amount of sample. Furthermore, negligible consumption of organic solvents was used in compliance with the green analytical chemistry principles. When compared to other well-established microextraction approaches, BAμE demonstrated better performance concerning recovery yields and sensitivity., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This manuscript addresses the determination of triazines (ametryn, atrazine, simazine, and terbutryn) in corn matrices using bar adsorptive microextraction coated with a selective molecularly imprinted polymer phase following microliquid desorption and high-performance liquid chromatography with diode array detection. The molecularly imprinted polymer was synthesized using atrazine as a template and methacrylic acid as a functional monomer. Assays performed in 25 mL of ultrapure water samples spiked at 8.0 μg/L yielded 80-120 % recoveries under the evaluated experimental conditions. The method showed an accuracy (0.2 < bias < 17.9%), precision (relative standard deviation <17.4%), convenient detection (0.2 μg/L), and quantification (0.7 μg/L) limits, as well as linear dynamic ranges (0.8-24.0 μg/L) with remarkable determination coefficients (R(2) > 0.9926). The proposed analytical method was applied to monitor triazines in three types of corn matrices using the standard addition methodology. Experiments performed in corn samples spiked with triazines at the trace level (8.0 μg/kg of each analyte) gave rise to recoveries (81.0-119.4%) with good reproducibility and robustness. The proposed methodology is also easy to implement and showed to be a good analytical alternative to monitor triazines in complex matrices, when compared with other sorption-based microextraction techniques., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We aimed to evaluate the ecological integrity of a large river, which receives agricultural and urban effluents and is used to water public supply. The fish species Astyanax bifasciatus was used as bioindicator during winter and spring 2012, and summer 2013 at the Middle Iguaçu River basin in Paraná state, Brazil. Water chemical and physical measures and ecotoxicological tests were carried out as well biochemical and genetic biomarkers in sampled fish in each period. The studied area was divided in three sample points: SP1, located where the water is collected to public supply; SP2, located in an urbanized area, and SP3, located at an urbanized area with the discharge of the sewage treatment. Although water chemical and physical analyzes were range of the Brazilian law to hydric bodies, anticholinesterasic effects were found in winter, oxidative stress in summer and spring. The higher genotoxic effect was in winter to all sample points. The temporal variation in biomarkers and the detection of caffeine in the water call attention to the water quality in this river mainly to be used to public supply., (Copyright © 2015 Elsevier Ltd. All rights reserved.)