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1.
Polymers (Basel) ; 16(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38675010

RESUMO

Water recycling and reuse are cornerstones of water management, which can be compromised by the presence of pollutants. Among these, pharmaceuticals can overcome standard water treatments and require sophisticated approaches to remove them. Sorption is an economically viable alternative limited by the need for sorbents with a sorption coefficient (Kd) higher than 500 L/kg. The cross-linking of dextrin (Dx) with divinyl sulfone (DVS) in the presence of 1 mmol or 5 mmol of ibuprofen (IBU) yields the insoluble polymers pDx1 and pDx5 with improved affinity for IBU and high selectivity towards erythromycin (ERY) and ERY Kd higher than 4 × 103 L/kg, when tested against a cocktail of six drugs. Characterization of the polymers shows that both pDx1 and pDx5 have similar properties, fast sorption kinetics, and ERY Kd of 13.3 × 103 for pDx1 and 6.4 × 103 for pDx5, representing 26.6 and 12.0 times the 500 L/kg threshold. The fact that new affinities and improvements in Kd can be achieved by cross-linking Dx in the presence of other molecules that promote pre-organization expands the applications of DVS cross-linked polysaccharides as sustainable, scalable, and environmentally friendly sorbents with a potential application in wastewater treatment plants (WTPs).

2.
Sensors (Basel) ; 24(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38543996

RESUMO

This paper presents the design, implementation, and validation of an on-blade sensor system for remote vibration measurement for low-capacity wind turbines. The autonomous sensor system was deployed on three wind turbines, with one of them operating in harsh weather conditions in the far south of Chile. The system recorded the acceleration response of the blades in the flapwise and edgewise directions, data that could be used for extracting the dynamic characteristics of the blades, information useful for damage diagnosis and prognosis. The proposed sensor system demonstrated reliable data acquisition and transmission from wind turbines in remote locations, proving the ability to create a fully autonomous system capable of recording data for monitoring and evaluating the state of health of wind turbine blades for extended periods without human intervention. The data collected by the sensor system presented in this study can serve as a foundation for developing vibration-based strategies for real-time structural health monitoring.

3.
J Hematol ; 12(6): 255-267, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38188474

RESUMO

Background: Allogeneic peripheral blood stem cell transplantation (PBSCT) has been increasing for the last years in Latin America. The objective of this study was to describe clinical outcomes in acute myeloid leukemia (AML) receiving allogeneic PBSCT between 2013 and 2019 in a single center of Cali, Colombia. Methods: A retrospective cohort study was conducted in Fundacion Valle del Lili. Patients diagnosed with AML who received an allogeneic PBSCT between 2013 and 2019 using human leukocyte antigen (HLA)-matched sibling donors (MSDs) or haploidentical related donors (HRDs) with myeloablative conditioning regimen were included. Cases with diagnosis of promyelocytic leukemia, myelodysplastic syndrome-related AML and therapy-related AML were excluded. Data were obtained directly from the hospital PBSCT database and clinical records. Results: A total of 50 patients were included (HRD, n = 32; MSD, n = 18). Sixty-two percent was in the first complete remission (CR1) at the time of the transplant, of which 26% were MSD and 74% were HRD. The European Group for Blood and Marrow Transplantation (EBMT) risk score was: 44% vs. 50% low, 28% vs. 28% intermediate and 28% vs. 22% high for MSD vs. HRD, respectively. Overall survival at 5 years for MSD was 62% (95% confidence interval (CI): 31-83%) and 43% (95% CI: 25-60%) for HRD. Event-free survival was 56% (95% CI: 26-78%) and 35.6% (95% CI: 18-53%), respectively. Non-relapse mortality at day-100 was 6% (95% CI: 0.8-35%) and 20% (95% CI: 9-39%). Relapse at5 years was 18% (95% CI: 4-58%) and 25% (95% CI: 10-52%). Overall mortality rate was 46%. The grade II-IV, III-IV acute graft-versus-host disease and severe chronic graft-versus-host disease was 44%, 11% and 12% for MSD, and 43%, 9% and 0% for HRD. Conclusion: These results underline that MSD remains the first donor choice for AML patients in CR1 when available. HRDs are still our next option among alternative donors. It is necessary to find strategies that have a positive impact on those outcomes that markedly affect the quality of allogeneic PBSCT and the prognosis of patients. Comparative, randomized, prospective studies with longer follow-up of haploidentical allogeneic PBSCT with other donor types are required to definitely establish its role among alternative donors.

4.
Chem Commun (Camb) ; 58(99): 13755-13758, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36416731

RESUMO

We show for the first time glycosylation of recombinant metallothioneins (MTs) produced in E. coli. Interestingly, our results show that the glycosylation level of the recombinant MTs is inversely proportional to the degree of protein structuration, and reflects their different metal preferences.


Assuntos
Escherichia coli , Metalotioneína , Proteínas Recombinantes , Escherichia coli/metabolismo , Metalotioneína/química , Metalotioneína/metabolismo , Metais/metabolismo , Glicosilação , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
5.
J Environ Manage ; 318: 115545, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35752006

RESUMO

Research has proven the adaptation of nitrite-oxidizing bacteria to unfavorable environmental conditions, and this work presents a novel concept to prevent nitrite oxidation during partial nitrification in wastewater. The approach is based on the real-time updating of mathematical models of the process to search for optimal set-points of pH and oxygen concentration in a continuous activated sludge reactor with a high sludge age (20.3 days). A heuristic optimization technique by 13 optimum set-points simultaneously maximized the degree of ammonia oxidation (α) and nitrite accumulation (ß), achieving an (α + ß) = 190% per day. The activated sludge reactor was conducted for 780 days under three control schemes: open-loop control, fuzzy model supervisory control and phenomenological supervisory control. The phenomenological supervisory control system achieved the best results, simultaneously reaching 95% ammonium oxidation and 90% nitrite accumulation. The Haldane kinetics were analyzed using steady-state concentrations of all nitrogen species, concluding that the simultaneous maximization of α + ß led to selecting set-points at the extreme values of the following ranges: pH = 7.5-8.5 and DO = 0.8-1.0 mg O2/L, which enabled the inhibition of one nitrifier species. At the same time, the other one was relieved from inhibition. The 16sRNA assays indicated that the nitrite-oxidizing bacteria presence (genera Nitrobacter and Nitrospira) shifted from 32% to less than 8% after 280 days of continuous operation with optimal pH and oxygen set-points.


Assuntos
Nitritos , Esgotos , Bactérias , Reatores Biológicos/microbiologia , Concentração de Íons de Hidrogênio , Nitrificação , Oxirredução , Oxigênio , Esgotos/microbiologia
6.
Antioxidants (Basel) ; 11(5)2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35624836

RESUMO

Heat stress is one of the abiotic stresses that leads to oxidative stress. To protect themselves, yeast cells activate the antioxidant response, in which cytosolic peroxiredoxin Tsa1 plays an important role in hydrogen peroxide removal. Concomitantly, the activation of the heat shock response (HSR) is also triggered. Nitro-fatty acids are signaling molecules generated by the interaction of reactive nitrogen species with unsaturated fatty acids. These molecules have been detected in animals and plants. They exert their signaling function mainly through a post-translational modification called nitroalkylation. In addition, these molecules are closely related to the induction of the HSR. In this work, the endogenous presence of nitro-oleic acid (NO2-OA) in Saccharomyces cerevisiae is identified for the first time by LC-MS/MS. Both hydrogen peroxide levels and Tsa1 activity increased after heat stress with no change in protein content. The nitroalkylation of recombinant Tsa1 with NO2-OA was also observed. It is important to point out that cysteine 47 (peroxidatic) and cysteine 171 (resolving) are the main residues responsible for protein activity. Moreover, the in vivo nitroalkylation of Tsa1 peroxidatic cysteine disappeared during heat stress as the hydrogen peroxide generated in this situation caused the rupture of the NO2-OA binding to the protein and, thus, restored Tsa1 activity. Finally, the amino acid targets susceptible to nitroalkylation and the modulatory effect of this PTM on the enzymatic activity of Tsa1 are also shown in vitro and in vivo. This mechanism of response was faster than that involving the induction of genes and the synthesis of new proteins and could be considered as a key element in the fine-tuning regulation of defence mechanisms against oxidative stress in yeast.

7.
CES med ; 35(3): 211-212, sep.-dic. 2021.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1374763
8.
CES med ; 35(2): 75-76, mayo-ago. 2021.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1364604
9.
Polymers (Basel) ; 13(10)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063481

RESUMO

Magnetite nanoparticles (MNPs) coated by branched poly (ethylene-imine) (PEI) were synthesized in a one-pot. Three molecular weights of PEI were tested, namely, 1.8 kDa (sample MNP-1), 10 kDa (sample MNP-2), and 25 kDa (sample MNP-3). The MNP-1 particles were further functionalized with folic acid (FA) (sample MNP-4). The four types of particles were found to behave magnetically as superparamagnetic, with MNP-1 showing the highest magnetization saturation. The particles were evaluated as possible hyperthermia agents by subjecting them to magnetic fields of 12 kA/m strength and frequencies ranging between 115 and 175 kHz. MNP-1 released the maximum heating power, reaching 330 W/g at the highest frequency, in the high side of reported values for spherical MNPs. In vitro cell viability assays of MNP-1 and MNP-4 against three cell lines expressing different levels of FA receptors (FR), namely, HEK (low expression), and HeLa (high expression), and HepG2 (high expression), demonstrated that they are not cytotoxic. When the cells were incubated in the presence of a 175 kHz magnetic field, a significant reduction in cell viability and clone formation was obtained for the high expressing FR cells incubated with MNP-4, suggesting that MNP-4 particles are good candidates for magnetic field hyperthermia and active targeting.

10.
J Anim Sci Biotechnol ; 12(1): 47, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33820552

RESUMO

BACKGROUND: Due to presence of drug-resistant Eimeria strains and raised public health safety concerns about drug residues in the meat, there is renewed interest in the search for natural alternatives to the coccidiosis control agents. This study was conducted to test the anticoccidial efficacy of oregano and Citrus spp.-based essential oils for broilers. METHODS: A total of 280 7-day-old broiler chicks were fed a control diet or diets with salinomycin or essential oils for up to 35 d of age. On d 14, half of the control groups and the treated groups were orally challenged with a coccidiosis vaccine at 25 times higher than the recommended vaccine dose. Control diet-fed chickens that were gavaged with phosphate-buffered saline were considered non-challenged control group. RESULTS: Eimeria challenge or dietary additives failed to affect growth performance during the 7 to 20 d growth period although essential oil-fed chickens exhibited the lowest body wight gain (P = 0.332) and the highest feed conversion ratio (P = 0.062). Oocysts in the litter were detected in the challenged control diet group and the challenged/essential oil-fed groups at 21 and 35 d, respectively. Superoxide dismutase activity in the serum was elevated (P = 0.059) in the salinomycin-fed chickens compared to the challenged controls. Alpha-1-acid glycoprotein was decreased by 28.7% in the salinomycin-fed chickens but increased by 38.1% in the essential oil group compared with the challenged control group. Challenged control group exhibited a significantly higher cooking loss of the thigh meat, compared to the non-challenged control diet group, which was marginally mitigated by dietary supplementation with essential oils. Chickens fed essential oil-added diet had the highest branched-chain fatty acids contents in the cecum. CONCLUSIONS: In conclusion, this study shows that oregano and Citrus-based essential oil preparation did not affect growth performance in broiler chickens challenged with the coccidiosis vaccine nor did Eimeria-specific duodenal lesion. However, dietary essential oil preparation lowered oocysts present in litter materials and altered branched-chain fatty acids in cecal digesta. Beneficial findings of the essential oil preparation on volatile fatty acids and oocysts output may warrant further research into assessing its effectiveness and its efficacy in pathogenic field-isolate Eimeria spp.-induced coccidiosis disease model.

11.
CES med ; 35(1): 1-3, ene.-abr. 2021.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1345577
12.
Int J Mol Sci ; 22(3)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498184

RESUMO

The synthesis and assembly of nanoparticles using green technology has been an excellent option in nanotechnology because they are easy to implement, cost-efficient, eco-friendly, risk-free, and amenable to scaling up. They also do not require sophisticated equipment nor well-trained professionals. Bionanotechnology involves various biological systems as suitable nanofactories, including biomolecules, bacteria, fungi, yeasts, and plants. Biologically inspired nanomaterial fabrication approaches have shown great potential to interconnect microbial or plant extract biotechnology and nanotechnology. The present article extensively reviews the eco-friendly production of metalloid nanoparticles, namely made of selenium (SeNPs) and tellurium (TeNPs), using various microorganisms, such as bacteria and fungi, and plants' extracts. It also discusses the methodologies followed by materials scientists and highlights the impact of the experimental sets on the outcomes and shed light on the underlying mechanisms. Moreover, it features the unique properties displayed by these biogenic nanoparticles for a large range of emerging applications in medicine, agriculture, bioengineering, and bioremediation.


Assuntos
Química Verde/métodos , Microbiologia Industrial/métodos , Nanopartículas Metálicas/química , Nanomedicina/métodos , Selênio/química , Telúrio/química , Animais , Humanos , Nanopartículas Metálicas/uso terapêutico
13.
Biomater Sci ; 9(5): 1728-1738, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33432316

RESUMO

The use of the specific binding properties of monoclonal antibody fragments such as single-chain variable fragments (ScFv) for the selective delivery of antitumor therapeutics for cancer cells is attractive due to their smaller size, low immunogenicity, and low-cost production. Although covalent strategies for the preparation of such ScFv-based therapeutic conjugates are prevalent, this approach is not straightforward, as it requires prior chemical activation and/or modification of both the ScFv and the therapeutics for the application of robust chemistries. A non-covalent alternative based on ScFv fused to maltose-binding protein (MBP) acting as a binding adapter is proposed for active targeted delivery. MBP-ScFv proves to be a valuable modular platform to synergistically bind maltose-derivatized therapeutic cargos through the MBP, while preserving the targeting competences provided by the ScFv. The methodology has been tested by using a mutated maltose-binding protein (MBP I334W) with an enhanced affinity toward maltose and an ScFv coding sequence toward the human epidermal growth factor receptor 2 (HER2). Non-covalent binding complexes of the resulting MBP-ScFv fusion protein with diverse maltosylated therapeutic cargos (a near-infrared dye, a maltosylated supramolecular ß-cyclodextrin container for doxorubicin, and non-viral polyplex gene vector) were easily prepared and characterized. In vitro and in vivo assays using cell lines that express or not the HER2 epitope, and mice xenografts of HER2 expressing cells demonstrated the capability and versatility of MBP-ScFv for diagnosis, imaging, and drug and plasmid active targeted tumor delivery. Remarkably, the modularity of the MBP-ScFv platform allows the flexible interchange of both the cargos and the coding sequence for the ScFv, allowing ad hoc solutions in targeting delivery without any further optimization since the MBP acts as a pivotal element.


Assuntos
Anticorpos de Cadeia Única , Animais , Anticorpos Monoclonais , Doxorrubicina , Maltose , Proteínas Ligantes de Maltose/genética , Camundongos , Anticorpos de Cadeia Única/genética
15.
CES med ; 34(spe): 32-33, dic. 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1339486
16.
J Environ Manage ; 273: 111150, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32768763

RESUMO

The main challenge for partial nitrification is to reach stable nitrite accumulation, which strongly depends on the nitrite-oxidizing bacteria (NOB) growth in the reactor. The on-line estimation of active biomass may enhance the decision-making process to maintain a high nitrite accumulation in the reactor. In this work, we propose an active biomass estimator based on ASM1 and on-line oxygen uptake rate measurements (OUR-E) in a sequencing batch reactor. In order to validate the OUR-E, two operating scenarios were applied during 200 days of operation: unfavorable (sludge retention time (SRT) = 40 d, pH = 7.6, dissolved oxygen (DO) = 2 mg/L) and favorable for partial nitrification (SRT = 10 d, pH = 8.5, DO = 2 mg/L). Furthermore, a second estimation method based on off-line measurements of N-species concentrations (Nsp-E) was implemented to evaluate the performance of the OUR-E. The OUR-E was able to predict a reduction in the NOB active fraction from 10.3% to 1.6% with nitrite accumulation over 80% when we shifted the operating scenario. Although both estimators predicted similar results, the OUR-E showed a better prediction quality than the Nsp-E, according to Theil's coefficient of inequality.


Assuntos
Reatores Biológicos , Nitrificação , Amônia , Biomassa , Nitritos , Oxirredução , Esgotos
17.
CES med ; 34(2): 92-92, mayo-ago. 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1285734
18.
Molecules ; 25(14)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708767

RESUMO

Bionanotechnology, the use of biological resources to produce novel, valuable nanomaterials, has witnessed tremendous developments over the past two decades. This eco-friendly and sustainable approach enables the synthesis of numerous, diverse types of useful nanomaterials for many medical, commercial, and scientific applications. Countless reviews describing the biosynthesis of nanomaterials have been published. However, to the best of our knowledge, no review has been exclusively focused on the in vivo biosynthesis of inorganic nanomaterials. Therefore, the present review is dedicated to filling this gap by describing the many different facets of the in vivo biosynthesis of nanoparticles (NPs) using living eukaryotic cells and organisms-more specifically, live plants and living biomass of several species of microalgae, yeast, fungus, mammalian cells, and animals. It also highlights the strengths and weaknesses of the synthesis methodologies and the NP characteristics, bio-applications, and proposed synthesis mechanisms. This comprehensive review also brings attention to enabling a better understanding between the living organisms themselves and the synthesis conditions that allow their exploitation as nanobiotechnological production platforms as these might serve as a robust resource to boost and expand the bio-production and use of desirable, functional inorganic nanomaterials.


Assuntos
Eucariotos/química , Compostos Inorgânicos/síntese química , Nanopartículas Metálicas/química , Nanoestruturas/química , Animais , Biomassa , Fungos/química , Fungos/genética , Compostos Inorgânicos/química , Mamíferos/genética , Microalgas/química , Microalgas/genética , Leveduras/química , Leveduras/genética
19.
Nanoscale ; 12(16): 9178-9185, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32297891

RESUMO

Chromophore-appended cyclodextrins combine the supramolecular loading capabilities of cyclodextrins (CDs) with the optical properties of the affixed chromophores. Among fluorescent materials, carbon dots (CNDs) are attractive and the feasibility of CND-appended CDs as sensors has been demonstrated by different authors. However, CNDs are intrinsically heterogeneous materials and their ulterior functionalization yields hybrid composites that are not well defined in terms of structure and composition. Inspired by the fluorescence properties of 5-oxo-1,2,3,5-tetrahydroimidazo[1,2-a]pyridine-7-carboxylic acid (IPCA), the most paradigmatic of the molecular fluorophores detected in CNDs, herein we report two highly efficient synthetic chemical strategies for the preparation of IPCA-appended CDs that behave as CND-based CD "turn off-on" biosensors suitable for the analysis of cholesterol and ß-galactosidase activity. We have deconstructed the CND-CD systems to demonstrate that (i) the role of CNDs is limited to acting as a support for the molecular fluorophores produced during their synthesis and (ii) the molecular fluorophores suffice for the determination of the enzymatic activity based on the quenching by p-nitrophenol as a sacrificial quencher.


Assuntos
Técnicas Biossensoriais , Carbono/química , Ciclodextrinas/química , Pontos Quânticos , Colesterol/sangue , Fluorescência , Corantes Fluorescentes/química , Humanos , Nitrofenóis/química , beta-Galactosidase/análise
20.
Hematol., Transfus. Cell Ther. (Impr.) ; 42(1): 18-24, Jan.-Mar. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1090467

RESUMO

Abstract Objective Cytomegalovirus infection and disease are significant causes of morbidity and mortality among patients with hematopoietic stem cell transplantation. The aim of this study was to assess the frequency of cytomegalovirus infection and characterize the patients who developed the disease. Methods A retrospective cohort study was performed among adult patients, recipients of allogeneic HSTC between 2008 and 2015. Taking into account the institutional protocol of prophylaxis infections in hematopoietic stem cell transplantation, patients received either preemptive therapy or prophylaxis with valganciclovir. Infection was defined as a positive pp65 antigenemia assay or PCR higher than 500 copies/mL. Disease was defined as viremia with evidence of end organ damage. Results Seventy patients were included, the median age was 36 years old (IQR 17-62). A total of 93% of the recipients had a positive serology. The Cytomegalovirus infection occurred in 59% of the patients. Eleven patients developed disease (16%), the most frequent manifestation being colitis, followed by pneumonitis and a single case of retinitis. There were no differences between the preemptive therapy or prophylaxis groups. The mean time of onset of the disease was day 94 post-transplant. Three patients developed disease with a viral load lower than 1000 copies/mL. Conclusion The incidence of cytomegalovirus infection after transplantation at our institution is high. It was found that the disease can occur with any level of viral load and is associated with high mortality.


Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Carga Viral
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