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1.
J Chromatogr A ; 1732: 465208, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39088897

RESUMEN

Piper gaudichaudianum Kunth essential oil (EO) is a natural source of bioactive components, having multiple therapeutic applications. Its chemical composition is highly variable, and strictly depends on abiotic factors, resulting in various biological activities. The present study details the utilization of multiple gas chromatographic techniques alongside nuclear magnetic resonance (NMR) spectroscopy to characterize the essential oil of Piper gaudichaudianum Kunth from Brazil. Seventy-six components were identified using GC-MS analysis, while enantio­selective multidimensional gas chromatography elucidated the enantiomeric distribution of eight chiral components, for the first time in the literature. Following GC-MS analysis, an unidentified component, constituting approximately 27 % of the total oil, prompted an isolation step through preparative gas chromatography. Through the combined use of nuclear magnetic resonance, GC-Fourier transform infrared spectroscopy (FTIR), and mass spectrometry (MS), the unknown molecule was structurally identified as 4-[(3E)­dec-3-en-1-yl]phenol. Remarkably, it was identified as a known molecule, gibbilimbol B, and not previously listed in any MS database. Subsequently, the spectrum was included in a commercial library, specifically the FFNSC 4.0 MS database, for the first time.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Aceites Volátiles , Piper , Piper/química , Aceites Volátiles/química , Aceites Volátiles/análisis , Brasil , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Aceites de Plantas/química , Cromatografía de Gases/métodos
2.
Methods Enzymol ; 700: 33-48, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38971606

RESUMEN

Biomolecular condensates play a major role in numerous cellular processes, including several that occur on the surface of lipid bilayer membranes. There is increasing evidence that cellular membrane trafficking phenomena, including the internalization of the plasma membrane through endocytosis, are mediated by multivalent protein-protein interactions that can lead to phase separation. We have recently found that proteins involved in the clathrin-independent endocytic pathway named Fast Endophilin Mediated Endocytosis can undergo liquid-liquid phase separation (LLPS) in solution and on lipid bilayer membranes. Here, the protein solution concentrations required for phase separation to be observed are significantly smaller compared to those required for phase separation in solution. LLPS is challenging to systematically characterize in cellular systems in general, and on biological membranes in particular. Model membrane approaches are more suitable for this purpose as they allow for precise control over the nature and amount of the components present in a mixture. Here we describe a method that enables the imaging of LLPS domain formation on solid supported lipid bilayers. These allow for facile imaging, provide long-term stability, and avoid clustering of vesicles and vesicle-attached features (such as buds and tethers) in the presence of multi-valent membrane interacting proteins.


Asunto(s)
Membrana Dobles de Lípidos , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Condensados Biomoleculares/química , Condensados Biomoleculares/metabolismo , Aciltransferasas/metabolismo , Aciltransferasas/química , Imagen Óptica/métodos , Membrana Celular/metabolismo , Membrana Celular/química , Endocitosis , Humanos , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo
3.
Artículo en Inglés | MEDLINE | ID: mdl-38994465

RESUMEN

Objective: To analyze marital outcomes, divorce or separation, and its association with demographic, socioeconomic, and clinicopathological factors among breast cancer (BC) survivors after 2-years of diagnosis. Methods: We performed a retrospective analysis of marital status at baseline and at years 1 and 2 of follow-up of women aged ≥ 18 years diagnosed with invasive BC participating in the AMAZONA III (GBECAM0115) study. The BC diagnosis occurred between January 2016 and March 2018 at 23 institutions in Brazil. Results: Of the 2974 women enrolled in AMAZONA III, 599 were married or living under common law at baseline. Divorce or separation occurred in 35 (5.8%) patients at 2 years of follow-up. In the multivariate analysis, public health insurance coverage was associated with a higher risk of marital status change (8.25% vs. 2.79%, RR 3.09, 95% CI 1.39 - 7.03, p = 0.007). Women who underwent mastectomy, adenomastectomy or skin-sparing mastectomy were associated with a higher risk of divorce or separation (8.1% vs. 4.49%, RR 1.97, 95 CI 1.04 - 3.72, p = 0.0366) than those who underwent breast-conserving surgery. Conclusion: Women covered by the public health system and those who underwent mastectomy, adenomastectomy or skin-sparing mastectomy were associated with a higher risk of divorce or separation. This evidence further supports the idea that long-term marital stability is associated with a complex interplay between socioeconomic conditions and stressors, such as BC diagnosis and treatment. ClinicalTrials Registration: NCT02663973.


Asunto(s)
Neoplasias de la Mama , Divorcio , Humanos , Femenino , Divorcio/estadística & datos numéricos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/cirugía , Estudios Retrospectivos , Persona de Mediana Edad , Adulto , Brasil/epidemiología , Estado Civil , Factores Socioeconómicos , Anciano , Factores de Riesgo , Supervivientes de Cáncer/estadística & datos numéricos
4.
Antioxidants (Basel) ; 13(7)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-39061871

RESUMEN

Early life stress (ELS) is a risk factor for the development of chronic diseases resulting from functional alterations of organs in the cardiorespiratory and renal systems. This work studied the changes in oxidative stress enzyme activities (EAs) of SOD, CAT, GPX, GR, GST, NOS, MDA, and FRAP in different organs (heart, liver, kidney, adrenal glands (AGs), and pancreas) of male and female Sprague-Dawley rat pups on postnatal day (PN) 15, immediately after basal and acute or chronic stress conditions were accomplished, as follows: basal control (BC; undisturbed maternal pups care), stress control (SC; 3 h maternal separation on PN15), basal maternal separation (BMS; daily 3 h maternal separation on PN 1-14), and stress maternal separation (SMS; daily 3 h maternal separation on PN 1-14 and 3 h maternal separation on PN15). Acute or long-term stress resulted in overall oxidative stress, increase in EA, and reduced antioxidant capacity in these organs. Some different response patterns, due to precedent SMS, were observed in specific organs, especially in the AGs. Acute stress exposure increases the EA, but chronic stress generates a response in the antioxidant system in some of the organs studied and is damped in response to a further challenge.

5.
Front Chem ; 12: 1393696, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38887701

RESUMEN

This article provides a comprehensive review of the state-of-the-art technology of polymeric mixed-matrix membranes for CO2/CH4 separation that can be applied in medium, small, and domestic biogas systems operating at low pressures (0.2-6 kPa). Critical data from the latest publications of CO2/CH4 separation membranes were analyzed, considering the ratio of CO2/CH4 permeabilities, the CO2 selectivity, the operating pressures at which the membranes were tested, the chemistry of the polymers studied and their gas separation mechanisms. And the different nanomaterials as fillers. The intrinsic microporous polymers (PIMs) were identified as potential candidates for biomethane purification due to their high permeability and selectivity, which are compatible with operation pressures below 1 bar, and as low as 0.2 bar. This scenario contrasts with other polymers that require pressures above 1 bar for operation, with some reaching 20 bar. Furthermore, the combination of PIM with GO in MMMs was found to not influence the permeability significantly, but to contribute to the membrane stability over time, by preventing the structural collapse of the membrane caused by aging. The systematic analysis here presented is a valuable resource for defining the future technological development of CO2/CH4 separation membranes for biogas biorefining.

6.
Protein Sci ; 33(7): e5085, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38923199

RESUMEN

Eukaryotic cells have developed intricate mechanisms for biomolecule transport, particularly in stressful conditions. This interdisciplinary study delves into unconventional protein secretion (UPS) pathways activated during starvation, facilitating the export of proteins bypassing most of the components of the classical secretory machinery. Specifically, we focus on the underexplored mechanisms of the GRASP's role in UPS, particularly in biogenesis and cargo recruitment for the vesicular-like compartment for UPS. Our results show that liquid-liquid phase separation (LLPS) plays a key role in the coacervation of Grh1, the GRASP yeast homologue, under starvation-like conditions. This association seems a precursor to the Compartment for Unconventional Protein Secretion (CUPS) biogenesis. Grh1's self-association is regulated by electrostatic, hydrophobic, and hydrogen-bonding interactions. Importantly, our study demonstrates that phase-separated states of Grh1 can recruit UPS cargo under starvation-like situations. Additionally, we explore how the coacervate liquid-to-solid transition could impact cells' ability to return to normal post-stress states. Our findings offer insights into intracellular protein dynamics and cell adaptive responses to stress.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Transporte de Proteínas , Separación de Fases
7.
Chemosphere ; 361: 142355, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38768787

RESUMEN

As global effects of water scarcity raise concerns and environmental regulations evolve, contemporary wastewater treatment plants (WWTPs) face the challenge of effectively removing a diverse range of contaminants of emerging concern (CECs) from municipal effluents. This study focuses on the assessment of advanced oxidation processes (AOPs), specifically UV-C/H2O2 and UV-C/Chlorine, for the removal of 14 target CECs in municipal secondary effluent (MSE, spiked with 10 µg L-1 of each CEC) or in the subsequent MSE nanofiltration retentate (NFR, no spiking). Phototreatments were carried out in continuous mode operation, with a hydraulic retention time of 3.4 min, using a tube-in-tube membrane photoreactor. For both wastewater matrices, UV-C photolysis (3.3 kJ L-1) exhibited high efficacy in removing CECs susceptible to photolysis, although lower treatment performance was observed for NFR. In MSE, adding 10 mg L-1 of H2O2 or Cl2 enhanced treatment efficiency, with UV-C/H2O2 outperforming UV-C/Chlorine. Both UV-C/AOPs eliminated the chronic toxicity of MSE toward Chlorella vulgaris. In the NFR, not only was the degradation of target CECs diminished, but chronic toxicity to C. vulgaris persisted after both UV-C/AOPs, with UV-C/Chlorine increasing toxicity due to potential toxic by-products. Nanofiltration permeate (NFP) exhibited low CECs and microbial content. A single chlorine addition effectively controlled Escherichia coli regrowth for 3 days, proving NFP potential for safe reuse in crop irrigation (<1 CFU/100 mL for E. coli; <1 mg L-1 for free chlorine). These findings provide valuable insights into the applications and limitations of UV-C/H2O2 and UV-C/Chlorine for distinct wastewater treatment scenarios.


Asunto(s)
Cloro , Filtración , Peróxido de Hidrógeno , Fotólisis , Rayos Ultravioleta , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua , Peróxido de Hidrógeno/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Eliminación de Residuos Líquidos/métodos , Cloro/química , Filtración/métodos , Purificación del Agua/métodos , Chlorella vulgaris/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Oxidación-Reducción
8.
Int J Biol Macromol ; 270(Pt 1): 132294, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38735602

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are molecules with two or more fused aromatic rings that occur naturally in the environment due to incomplete combustion of organic substances. However, the increased demand for fossil fuels in recent years has increased anthropogenic activity, contributing to the environmental concentration of PAHs. The enzyme chlorocatechol 1,2-dioxygenase from Pseudomonas putida (Pp 1,2-CCD) is responsible for the breakdown of the aromatic ring of catechol, making it a potential player in bioremediation strategies. Pp 1,2-CCD can tolerate a broader range of substrates, including halogenated compounds, than other dioxygenases. Here, we report the construction of a chimera protein able to form biomolecular condensates with potential application in bioremediation. The chimera protein was built by conjugating Pp 1,2-CCD to low complex domains (LCDs) derived from the DEAD-box protein Dhh1. We showed that the chimera could undergo liquid-liquid phase separation (LLPS), forming a protein-rich liquid droplet under different conditions (variable protein and PEG8000 concentrations and pH values), in which the protein maintained its structure and main biophysical properties. The condensates were active against 4-chlorocatechol, showing that the chimera droplets preserved the enzymatic activity of the native protein. Therefore, it constitutes a prototype of a microreactor with potential use in bioremediation.


Asunto(s)
Biodegradación Ambiental , Dioxigenasas , Hidrocarburos Policíclicos Aromáticos , Dioxigenasas/metabolismo , Dioxigenasas/química , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/metabolismo , Pseudomonas putida/enzimología , Catecoles/metabolismo , Catecoles/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo
9.
J Environ Sci (China) ; 143: 99-115, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38644027

RESUMEN

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air pollution. In Mexico, the total lockdown period took place during the dry-hot season when biomass burning activity is enhanced. Here, we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central Mexico. The studied period covers the lockdown phases 2 and 3, and the first month of the New Normal. We applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the Megalopolis. The results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions, impacted the PBL development during phase 3 and favored transition and mixed NOx-limited and VOC-limited regional regimes. This contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency estimations. Given the Megalopolis contribution to economic and societal development at national scale, our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes. A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Biomasa , COVID-19 , Ozono , Ozono/análisis , México , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Contaminación del Aire/análisis , Monitoreo del Ambiente
10.
Dent Med Probl ; 61(2): 269-278, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38686969

RESUMEN

Nickel-titanium (NiTi) file separation during endodontic treatment is an undesirable event. This phenomenon needs to be understood by knowing the factors influencing fracture in endodontic files. There is a large amount of literature where these factors and their influence have been studied, increasing the knowledge about the mechanisms involved, mainly related to wire technology, file shapes and geometry, operator manipulation, the anatomy of the root canal, and the irrigation and sterilization processes. As many factors are involved, the complexity of the fracture phenomena increases and the isolated correlation of one factor with the file fracture becomes a small part of comprehending the separation phenomena. This thematic review aims to compile important reports from 2014 to 2022 on the factors influencing NiTi file separation. The information obtained was classified into wire technology, file geometry, operational aspects, irrigation and sterilization, and anatomy. For this purpose, the Scopus, Web of Science and ScienceDirect databases were consulted using a search string. Filters were applied to consolidate the final set of relevant papers covering the subject of factors influencing endodontic file separation. It was found that the fracture of NiTi files incorporates different mechanisms that operate simultaneously during the endodontic procedure and strongly affect the instrument performance. The collected information promotes good practices to prevent file separation.


Asunto(s)
Níquel , Preparación del Conducto Radicular , Titanio , Humanos , Preparación del Conducto Radicular/instrumentación , Falla de Equipo , Diseño de Equipo , Esterilización , Instrumentos Dentales
11.
Environ Technol ; : 1-12, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38449387

RESUMEN

Incidents of mining dam failure have compromised the water quality, threatening the water supply. Different strategies are sought to restore the impacted area and to guarantee the water supply. One example is water treatment plants that treat high-polluted waters within the required limits for their multiple usages. The current study assesses the integration of reverse osmosis (RO) to a river water treatment plant (RWTP) installed in Brumadinho (Minas Gerais, Brazil) to treat the water from the Ferro-Carvão stream impacted by the B1 dam rupture in 2019. The RWTP started eleven months after the mining dam rupture and is equipped with eight coagulation-flocculation tanks followed by eight pressurised filters. A pilot RO plant was installed to polish the water treated by the RWTP. Water samples were collected at different points of the water treatment plant and were characterised by their physical, chemical, and biological parameters (160 in total). The results were compared with the historical data (1997-2022) to reveal the alterations in the water quality after the rupture event. The compliance with both parameters was only achieved after the RO treatment, which acted as an additional barrier to 30 contaminants. The water quality indexes (WQI) suggested that the raw surface water, even eleven months after the incident, was unfit for consumption (WQI: 133.9) whereas the reverse osmosis permeate was ranked as excellent in the rating grid (WQI: 23.7).

12.
Waste Manag ; 179: 192-204, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38484540

RESUMEN

Research to prevent releases of brominated flame retardants listed as persistent organic pollutants by the Stockholm Convention (POP-BFRs) was conducted through an international cooperation project in Colombia. Six waste electrical and electronic equipment (WEEE) management facilities implemented: 1) sorting e-waste by product type and color (black, white, and other; henceforth called chromoproducts), 2) sampling test products and their plastic fraction (called sets, separated by polymer type), 3) monitoring mass, bromine and antimony contents by hand-held X-ray fluorescence (XRF) and POP-BFRs such as polybrominated diphenyl ethers (PBDEs) by gas chromatography and mass spectrometry (GC-MS), and 4) differentiated treatment according to categories that used the Restriction of Hazardous Substances in Electrical and Electronic Equipment Directive (RoHS) hazardousness threshold of 1000 mg ∑PBDEs/kg. This scheme led to the proposal of a methodology for WEEE management called the "chromoproduct approach". 994,230 products were managed and grouped into 222 chromoproducts, from which 77 were analyzed: 50 below RoHS hazardousness (BRH), 16 above RoHS hazardousness (ARH), and 11 unknown RoHS hazardousness (URH). XRF indicators using bromine and antimony contents could rule out pollution in BRH chromoproducts; however, categorization still required GC-MS. One ARH plastics sample had 3620 mg ∑PBDEs/kg, while no POP-BFRs were found in the BRH plastics sample. The implementation of the chromoproduct approach traced 153.6 tonnes of ARH plastics. BRH plastics composition was estimated and used in a pilot-scale closed-loop economic activity. The chromoproduct approach seems promising for avoiding POP-BFR releases and promoting the upcycling of recyclable e-waste plastics.


Asunto(s)
Residuos Electrónicos , Retardadores de Llama , Plásticos/análisis , Residuos Electrónicos/análisis , Colombia , Antimonio/análisis , Bromo/análisis , Residuos/análisis , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/análisis
13.
Biosens Bioelectron ; 255: 116211, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38537428

RESUMEN

Exosomes are nanovesicles present in all the biological fluids, making them attractive as non-invasive biomarkers for diseases like cancer, among many others. However, exosomes are complex to separate and detect, requiring comprehensive molecular characterization for their routine use in diagnostics. This study explores the use of peptides as cost-effective and stable alternatives to antibodies for exosome binding. To achieve that, phage display technology was employed to select peptides with high specificity for target molecules in exosomes. Specifically, a selected peptide was evaluated for its ability to selectively bind breast cancer-derived exosomes. Proteomic analysis identified 38 protein candidates targeted by the peptide on exosome membranes. The binding of the peptide to breast cancer-derived exosomes was successfully demonstrated by flow cytometry and magneto-actuated immunoassays. Furthermore, an electrochemical biosensor was also tested for breast cancer-derived exosome detection and quantification. The peptide demonstrated effective binding to exosomes from aggressive cancer cell lines, offering promising results in terms of specificity and recovery. This research shows potential for developing rapid, accessible diagnostic tools for breast cancer, especially in low-resource healthcare settings.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Exosomas , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Exosomas/química , Biomarcadores de Tumor/análisis , Proteómica , Péptidos/metabolismo
14.
Physiol Behav ; 280: 114529, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38555006

RESUMEN

Early-life stress and subsequent high-calorie diets during adolescence are known to be risk factors for developing metabolic and psychological disorders. Although non-nutritive sweeteners such as stevia and sucralose have been a useful alternative to reduce sugar consumption, the effects of prolonged consumption of these sweeteners on metabolism and behavior in adolescents remain unclear. Here, we evaluated the effects of early-stress followed by access to stevia or sucralose during adolescence on weight gain, glycemia, and anxiety-related behaviors in male and female rats. During postnatal days (PNDs) 1-21, pups were separated twice a day, for 180 min each time, from their dam nest while non-separated pups served as controls. The pups were weaned, separated by sex and randomly distributed into the stevia, sucralose and water conditions. During PNDs 26-50, two bottles containing water and stevia or sucralose were placed in the animal home-cages, and body weight and blood glucose measures were scored. On PNDs 50 and 51, behavioral measures were obtained in the open-field test. Results showed that male rats consuming stevia reduced body weight gain, blood glucose and increased locomotion. Early-stress led to low blood glucose and alterations in anxiety and locomotion-related behaviors in a sex-dependent manner. Moreover, sucralose access during adolescence reversed the effects of early-stress on anxiety-related behaviors in female rats. The results suggest that the consumption of stevia and sucralose could be an alternative for the replacement of sugar-sweetened beverages, especially in adolescents who have had adverse early-life experiences.


Asunto(s)
Ansiedad , Glucemia , Stevia , Estrés Psicológico , Sacarosa , Sacarosa/análogos & derivados , Edulcorantes , Aumento de Peso , Animales , Femenino , Masculino , Sacarosa/farmacología , Aumento de Peso/efectos de los fármacos , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Edulcorantes/farmacología , Ratas , Animales Recién Nacidos , Conducta Exploratoria/efectos de los fármacos , Conducta Exploratoria/fisiología , Caracteres Sexuales , Ratas Wistar
15.
Waste Manag Res ; : 734242X241231402, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38385333

RESUMEN

Landfills are the destination of most of the refuse generated whereas composting, material recycling, and Waste-to-Energy (WtE) technologies are not commonly employed in developing countries. However, the destination for energy purposes could be supplied with this refuse, improving the viability of energy use. Thus, this article raises some questions to identify aspects that could encourage its use as refuse-derived fuel (RDF) in these countries. Among them, does environmental education affect the municipal solid waste (MSW) source separation with emphasis on a destination? Can selective collection and extended producer responsibility (EPR) affect the MSW for energy recovery? Is there competition between the recycling market and the energy market for RDF? A systematic review of the literature was conducted to gather data and provide answers to such questions. This enabled to observe that EPR, selective collect expansion and source separation influence the quantity and quality of waste sent for energy use. Both internal and external factors impact on source separation. Additionally, there is evidence to support that despite several studies showing their technical, economic, environmental and social viability, the methods of energy usage of the refuse still need to improve their deployment in developing countries. In addition to identifying the main research gaps to be filled in future studies, the article also identified the instruments of MSW management that are to be applied in developing countries to divert recyclable and organic waste from landfill.

16.
Sci Total Environ ; 922: 171281, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38417526

RESUMEN

Separation of domestic effluents at the source and the utilization of low-flush toilets offer alternative approaches for developing efficient wastewater treatment systems while promoting energy generation through anaerobic digestion. This study focused on assessing toilet usage in Mexico and exploring the potential of anaerobic co-digestion of brown water (feces) and toilet paper as influential factors in wastewater treatment systems. A survey was conducted on a representative sample of Mexicans to gather information on toilet usage frequency, toilet paper use and disposal practices, as well as the type and quantity of commercial disinfectants and pharmaceutical compounds they use or consume. The survey revealed that per capita toilet paper consumption is 2.9 kg annually, that 58 % of respondents do not dispose used paper in the toilet, and that about 47 % use two to three cleaning and disinfection products. Notably, 97 % of the sampled Mexican population expressed a willingness to transition to more eco-friendly toilet options. Subsequently, in a second step, the anaerobic co-digestion of brown water with toilet paper was evaluated, demonstrating a relatively high production of volatile fatty acids but low methane production. This suggests an efficient hydrolysis/acidogenesis process coupled with restrained methanogenesis, probably due to pH decrease caused by acidogenesis. This study underscores that toilet paper and brown water are potential suitable substrates for anaerobic co-digestion. Furthermore, it sheds light on the behaviors of Mexican society regarding bathroom use and cleaning, contributing to the establishment of foundations for wastewater treatment systems with effluent separation at the source.


Asunto(s)
Aparatos Sanitarios , Pueblos de América del Norte , Aguas del Alcantarillado , Humanos , Anaerobiosis , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos , México , Estudios de Factibilidad , Encuestas y Cuestionarios , Metano , Reactores Biológicos
17.
Artículo en Inglés | MEDLINE | ID: mdl-38320436

RESUMEN

This study investigated the purification of bromelain obtained from pineapple fruit using a new adsorbent for immobilized metal ion affinity chromatography (IMAC), with chlorophyll obtained from plant leaves as a chelating agent. The purification of bromelain was evaluated in batches from the crude extract of pineapple pulp (EXT), and the extract precipitated with 50 % ammonium sulfate (EXT.PR), the imidazole buffer (200 mM, pH 7.2) being analyzed and sodium acetate buffer, pH 5.0 + 1.0 NaCl as elution solutions. All methods tested could separate forms of bromelain with molecular weights between ±21 to 25 kDa. Although the technique using EXT.PR stood out in terms of purity, presenting a purification factor of around 3.09 ± 0.31 for elution with imidazole and 4.23 ± 0.12 for acetate buffer solution. In contrast, the EXT methods obtained values between 2.44 ± 0.23 and 3.21 ± 0.74 for elution with imidazole and acetate buffer, respectively, for purification from EXT.PR has lower yield values (around 5 %) than EXT (around 15 %). The number of steps tends to reduce yield and increase process costs, so the purification process in a monolithic bed coupled to the chromatographic system using the crude extract was evaluated. The final product obtained had a purification factor of 6, with a specific enzymatic activity of 59.61 ± 0.00 U·mg-1 and a yield of around 39 %, with only one band observed in the SDS-PAGE electrophoresis analysis, indicating that the matrix produced can separate specific proteins from the total fraction in the raw material. The IMAC matrix immobilized with chlorophyll proved promising and viable for application in protease purification processes.


Asunto(s)
Ananas , Bromelaínas , Acetatos , Ananas/química , Bromelaínas/aislamiento & purificación , Cromatografía de Afinidad/métodos , Imidazoles , Extractos Vegetales/química
18.
Heliyon ; 10(3): e25377, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38322940

RESUMEN

Molecular diagnostic methods to detect and quantify viral RNA in clinical samples rely on the purification of the genetic material prior to reverse transcription polymerase chain reaction (qRT-PCR). Due to the large number of samples processed in clinical laboratories, automation has become a necessity in order to increase method processivity and maximize throughput per unit of time. An attractive option for isolating viral RNA is based on the magnetic solid phase separation procedure (MSPS) using magnetic microparticles. This method offers the advantage over other alternative methods of making it possible to automate the process. In this study, we report the results of the MSPS method based on magnetic microparticles obtained by a simple synthesis process, to purify RNA from oro- and nasopharyngeal swab samples of patients suspected of COVID-19 provided by three diagnostic laboratories located in the Buenos Aires Province, Argentina. Magnetite nanoparticles of Fe3O4 (MNPs) were synthesized by the coprecipitation method and then coated with silica (SiO2) produced by hydrolysis of tetraethyl orthosilicate (TEOS). After preliminary tests on samples from the A549 human lung cell line and swabs, an extraction protocol was developed. The quantity and purity of the RNA obtained were determined by gel electrophoresis, spectrophotometry, and qRT-PCR. Tests on samples from naso- and oropharyngeal swabs were performed in order to validate the method for RNA purification in high-throughput SARS-CoV-2 diagnosis by qRT-PCR. The method was compared to the spin columns method and the automated method using commercial magnetic particles. The results show that the method developed is efficient for RNA extraction from nasal and oropharyngeal swab samples, and also comparable to other extraction methods in terms of sensitivity for SARS-CoV-2 detection. Of note, this procedure and reagents developed locally were intended to overcome the shortage of imported diagnostic supplies as the sudden spread of COVID-19 required unexpected quantities of nucleic acid isolation and diagnostic kits worldwide.

19.
Int J Biol Macromol ; 259(Pt 2): 129330, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38218270

RESUMEN

DEAD-box helicases are global regulators of liquid-liquid phase separation (LLPS), a process that assembles membraneless organelles inside cells. An outstanding member of the DEAD-box family is DDX3X, a multi-functional protein that plays critical roles in RNA metabolism, including RNA transcription, splicing, nucleocytoplasmic export, and translation. The diverse functions of DDX3X result from its ability to bind and remodel RNA in an ATP-dependent manner. This capacity enables the protein to act as an RNA chaperone and an RNA helicase, regulating ribonucleoprotein complex assembly. DDX3X and its orthologs from mouse, yeast (Ded1), and C. elegans (LAF-1) can undergo LLPS, driving the formation of neuronal granules, stress granules, processing bodies or P-granules. DDX3X has been related to several human conditions, including neurodevelopmental disorders, such as intellectual disability and autism spectrum disorder. Although the research into the pathogenesis of aberrant biomolecular condensation in neurodegenerative diseases is increasing rapidly, the role of LLPS in neurodevelopmental disorders is underexplored. This review summarizes current findings relevant for DDX3X phase separation in neurodevelopment and examines how disturbances in the LLPS process can be related to neurodevelopmental disorders.


Asunto(s)
Trastorno del Espectro Autista , ARN Helicasas DEAD-box , Trastornos del Neurodesarrollo , Animales , Humanos , Ratones , Trastorno del Espectro Autista/genética , Caenorhabditis elegans/metabolismo , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Trastornos del Neurodesarrollo/genética , ARN/metabolismo , Saccharomyces cerevisiae/metabolismo
20.
Sci Bull (Beijing) ; 69(2): 218-226, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38087739

RESUMEN

Atomic layer deposition (ALD) offers unique capabilities to fabricate atomically engineered porous materials with precise pore tuning and multi-functionalization for diverse applications like advanced membrane separations towards sustainable energy-water systems. However, current ALD technique is inhibited on most non-polar polymeric membranes due to lack of accessible nucleation sites. Here, we report a facile method to efficiently promote ALD coating on hydrophobic surface of polymeric membranes via novel protein activation/sensitization. As a proof of concept, TiO2 ALD-coated membranes activated by bovine serum albumin exhibit remarkable superhydrophilicity, ultralow underwater crude oil adhesion, and robust tolerance to rigorous environments including acid, alkali, saline, and ethanol. Most importantly, excellent cyclable crude oil-in-water emulsion separation performance can be achieved. The mechanism for activation/sensitization is rooted in reactivity for a particular set of amino acids. Furthermore, the universality of protein-sensitized ALD is demonstrated using common egg white, promising numerous potential usages in biomedical engineering, environmental remediation, low-carbon manufacturing, catalysis, and beyond.

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