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1.
World J Gastroenterol ; 30(17): 2302-2307, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38813047

RESUMEN

In this editorial, we discuss the article in the World Journal of Gastroenterology. The article conducts a meta-analysis of the diagnostic accuracy of the urea breath test (UBT), a non-invasive method for detecting Helicobacter pylori (H. pylori) infection in humans. It is based on radionuclide-labeled urea. Various methods, both invasive and non-invasive, are available for diagnosing H. pylori infection, including endoscopy with biopsy, serology for immunoglobulin titers, stool antigen analysis, and UBT. Several guidelines recommend UBTs as the primary choice for diagnosing H. pylori infection and for reexamining after eradication therapy. It is used to be the first choice non-invasive test due to their high accuracy, specificity, rapid results, and simplicity. Moreover, its performance remains unaffected by the distribution of H. pylori in the stomach, allowing a high flow of patients to be tested. Despite its widespread use, the performance characteristics of UBT have been inconsistently described and remain incompletely defined. There are two UBTs available with Food and Drug Administration approval: The 13C and 14C tests. Both tests are affordable and can provide real-time results. Physicians may prefer the 13C test because it is non-radioactive, compared to 14C which uses a radioactive isotope, especially in young children and pregnant women. Although there was heterogeneity among the studies regarding the diagnostic accuracy of both UBTs, 13C-UBT consistently outperforms the 14C-UBT. This makes the 13C-UBT the preferred diagnostic approach. Furthermore, the provided findings of the meta-analysis emphasize the significance of precise considerations when choosing urea dosage, assessment timing, and measurement techniques for both the 13C-UBT and 14C-UBT, to enhance diagnostic precision.


Asunto(s)
Pruebas Respiratorias , Dispepsia , Infecciones por Helicobacter , Helicobacter pylori , Urea , Humanos , Pruebas Respiratorias/métodos , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/inmunología , Urea/análisis , Urea/metabolismo , Dispepsia/microbiología , Dispepsia/diagnóstico , Adulto , Isótopos de Carbono/análisis , Sensibilidad y Especificidad , Radioisótopos de Carbono
2.
Sci Rep ; 14(1): 12168, 2024 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-38806510

RESUMEN

The bioartificial liver (BAL) system can potentially rescue acute liver failure (ALF) patients by providing partial liver function until a suitable donor liver can be found or the native liver has self-regenerated. In this study, we established a suitable cryopreservation process for the development of an off-the-shelf BAL system. The viability of hepatocyte spheroids cryopreserved in liquid nitrogen was comparable to that of fresh primary hepatocyte spheroids. When hepatocyte spheroids were subjected to cryopreservation in a deep freezer, no statistically significant differences were observed in ammonia removal rate or urea secretion rate based on the cryopreservation period. However, the functional activity of the liver post-cryopreservation in a deep freezer was significantly lower than that observed following liquid nitrogen cryopreservation. Moreover, cryopreserving spheroid hydrogel beads in a deep freezer resulted in a significant decrease (approximately 30%) in both ammonia removal and urea secretion rates compared to the group cryopreserved in liquid nitrogen. The viabilities of spheroid hydrogel beads filled into the bioreactor of a BAL system were similar across all four groups. However, upon operating the BAL system for 24 h, the liver function activity was significantly higher in the group comprising hydrogel beads generated after thawing hepatocyte spheroids cryopreserved in liquid nitrogen. Consequently, the manufacturing of beads after the cryopreservation of hepatocyte spheroids is deemed the most suitable method, considering efficiency, economic feasibility, and liver function activity, for producing a BAL system.


Asunto(s)
Criopreservación , Hepatocitos , Hígado Artificial , Esferoides Celulares , Hepatocitos/metabolismo , Hepatocitos/citología , Criopreservación/métodos , Esferoides Celulares/metabolismo , Esferoides Celulares/citología , Animales , Supervivencia Celular , Masculino , Temperatura , Ratas , Urea/metabolismo , Humanos , Amoníaco/metabolismo , Fallo Hepático Agudo/terapia , Fallo Hepático Agudo/metabolismo , Hígado/metabolismo , Hígado/citología
4.
Am J Dent ; 37(2): 78-84, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38704850

RESUMEN

PURPOSE: To evaluate how fluoride- or chitosan-based toothpaste used during at-home bleaching affects enamel roughness, tooth color, and staining susceptibility. METHODS: Bovine enamel blocks were submitted to a 14-day cycling regime considering a factorial design (bleaching agent x toothpaste, 2 x 3), with n=10: (1) bleaching with 16% carbamide peroxide (CP) or 6% hydrogen peroxide (HP), and (2) daily exposure of a fluoride (1,450 ppm F-NaF) toothpaste (FT), chitosan-based toothpaste (CBT), or distilled water (control). Then, 24 hours after the last day of bleaching procedure the samples were exposed to a coffee solution. Color (ΔEab, ΔE00, L*, a*, b*) and roughness (Ra, µm) analyses were performed to compare the samples initially (baseline), after bleaching, and after coffee staining. The results were evaluated by linear models for repeated measures (L*, a*, b*, and Ra), 2-way ANOVA (ΔEab, ΔE00) and Tukey's test (α= 0.05). RESULTS: After the at-home bleaching procedure (toothpaste vs. time, P< 0.0001), the toothpaste groups presented a statistically lower Ra than the control (CBT 0.05). After coffee exposure, CBT presented lower ΔEab and ΔE00 values in the HP groups (toothpaste, P< 0.0001), and lower b* and a* values in the CP groups (toothpaste vs. time, P= 0.004). CLINICAL SIGNIFICANCE: Fluoride or chitosan delivered by toothpaste can reduce surface alterations of the enamel during at-home bleaching, without affecting bleaching efficacy.


Asunto(s)
Peróxido de Carbamida , Quitosano , Esmalte Dental , Peróxido de Hidrógeno , Blanqueadores Dentales , Blanqueamiento de Dientes , Decoloración de Dientes , Pastas de Dientes , Quitosano/farmacología , Pastas de Dientes/farmacología , Animales , Bovinos , Blanqueamiento de Dientes/métodos , Esmalte Dental/efectos de los fármacos , Blanqueadores Dentales/farmacología , Peróxido de Hidrógeno/farmacología , Peróxido de Carbamida/farmacología , Propiedades de Superficie , Fluoruros/farmacología , Color , Urea/análogos & derivados , Urea/farmacología , Café , Peróxidos/farmacología
5.
Water Res ; 256: 121638, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691899

RESUMEN

In this study, we investigated the recovery of nitrogen (N) and phosphorus (P) from fresh source-separated urine with a novel electrochemical cell equipped with a magnesium (Mg) anode and carbon-based gas-diffusion cathode. Recovery of P, which exists primarily as phosphate (PO43-) in urine, was achieved through pH-driven precipitation. Maximizing N recovery requires simultaneous approaches to address urea and ammonia (NH3). NH3 recovery was possible through precipitation in struvite with soluble Mg supplied by the anode. Urea was stabilized with electrochemically synthesized hydrogen peroxide (H2O2) from the cathode. H2O2 concentrations and resulting urine pH were directly proportional to the applied current density. Concomitant NH3 and PO43- precipitation as struvite and urea stabilization via H2O2 electrosynthesis was possible at lower current densities, resulting in urine pH under 9.2. Higher current densities resulted in urine pH over 9.2, yielding higher H2O2 concentrations and more consistent stabilization of urea at the expense of NH3 recovery as struvite; PO43- precipitation still occurred but in the form of calcium phosphate and magnesium phosphate solids.


Asunto(s)
Electrodos , Peróxido de Hidrógeno , Magnesio , Fósforo , Urea , Urea/química , Fósforo/química , Magnesio/química , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Orina/química , Fosfatos/química , Estruvita/química , Amoníaco/química , Compuestos de Magnesio/química , Nitrógeno/química , Humanos
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124357, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38692110

RESUMEN

This study described the preparation of an azide covalent organic framework-embedded molecularly imprinted polymers (COFs(azide)@MIPs) platform for urea adsorption and indirect ethyl carbamate (EC) removal from Chinese yellow rice wine (Huangjiu). By modifying the pore surface of COFs using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, COFs(azide) with a high fluorescence quantum yield and particular recognition ability were inventively produced. In order to selectively trap urea, the COFs(azide) were encased in an imprinted shell layer via imprinting technology. With a detection limit (LOD) of 0.016 µg L-1 (R2 = 0.9874), the COFs(azides)@MIPs demonstrated a good linear relationship with urea in the linear range of 0-5 µg L-1. Using real Huangjiu samples, the spiking recovery trials showed the viability of this sensing platform with recoveries ranging from 88.44 % to 109.26 % and an RSD of less than 3.40 %. The Huangjiu processing model system achieved 38.93 % EC reduction by COFs(azides)@MIPs. This research will open up new avenues for the treatment of health problems associated with fermented alcoholic beverages, particularly Huangjiu, while also capturing and removing hazards coming from food.


Asunto(s)
Polímeros Impresos Molecularmente , Urea , Uretano , Vino , Uretano/análisis , Uretano/química , Polímeros Impresos Molecularmente/química , Urea/análisis , Urea/química , Vino/análisis , Espectrometría de Fluorescencia/métodos , Azidas/química , Límite de Detección , Adsorción , Estructuras Metalorgánicas/química , Impresión Molecular/métodos
7.
Appl Microbiol Biotechnol ; 108(1): 342, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789552

RESUMEN

Chemoautotrophic canonical ammonia oxidizers (ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB)) and complete ammonia oxidizers (comammox Nitrospira) are accountable for ammonia oxidation, which is a fundamental process of nitrification in terrestrial ecosystems. However, the relationship between autotrophic nitrification and the active nitrifying populations during 15N-urea incubation has not been totally clarified. The 15N-labeled DNA stable isotope probing (DNA-SIP) technique was utilized in order to study the response from the soil nitrification process and the active nitrifying populations, in both acidic and neutral paddy soils, to the application of urea. The presence of C2H2 almost completely inhibited NO3--N production, indicating that autotrophic ammonia oxidation was dominant in both paddy soils. 15N-DNA-SIP technology could effectively distinguish active nitrifying populations in both soils. The active ammonia oxidation groups in both soils were significantly different, AOA (NS (Nitrososphaerales)-Alpha, NS-Gamma, NS-Beta, NS-Delta, NS-Zeta and NT (Ca. Nitrosotaleales)-Alpha), and AOB (Nitrosospira) were functionally active in the acidic paddy soil, whereas comammox Nitrospira clade A and Nitrosospira AOB were functionally active in the neutral paddy soil. This study highlights the effective discriminative effect of 15N-DNA-SIP and niche differentiation of nitrifying populations in these paddy soils. KEY POINTS: • 15N-DNA-SIP technology could effectively distinguish active ammonia oxidizers. • Comammox Nitrospira clade A plays a lesser role than canonical ammonia oxidizers. • The active groups in the acidic and neutral paddy soils were significantly different.


Asunto(s)
Amoníaco , Archaea , Bacterias , Nitrificación , Isótopos de Nitrógeno , Oxidación-Reducción , Microbiología del Suelo , Amoníaco/metabolismo , Archaea/metabolismo , Archaea/clasificación , Archaea/genética , Isótopos de Nitrógeno/metabolismo , Isótopos de Nitrógeno/análisis , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética , Suelo/química , Urea/metabolismo , Filogenia
8.
PLoS One ; 19(5): e0303348, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38787867

RESUMEN

AIMS: We assessed eligibility for omecamtiv mecarbil (OM) in a real-world cohort with heart failure with reduced ejection fraction (HFrEF) according to the selection criteria of the GALACTIC-HF trial (trial scenario) and selected trial´s criteria more likely to impact real-world use (pragmatic scenario). METHODS AND RESULTS: We included 31,015 patients with HFrEF lasting ≥3 months and registered in the Swedish HF registry between 2000-2021. Trial eligibility was calculated by applying all the GALACTIC-HF selection criteria. The pragmatic scenario considered only the New York Heart Association class, history of worsening HF, N-terminal pro-B-type natriuretic peptides (NT-proBNP), blood pressure and renal failure criteria defined as in the trial. Eligibility for OM in chronic HFrEF was 21% and 36% in the trial and pragmatic scenarios, respectively. Eligibility was higher in those with EF<30% (trial: 27%, pragmatic: 44%), in-patients (trial:30%, pragmatic:57%), severe HF (trial: 35%, pragmatic: 60%), NYHA class III-IV (trial: 26%, pragmatic: 45%), and NT-proBNP≥5,000pg/mL (trial: 30%, pragmatic: 51%). The criteria that most limited eligibility were history of a recent worsening HF event (60% eligible in chronic HFrEF), elevated NT-proBNP (82% eligible), and deviating blood pressure (82% eligible). Overall, eligible patients were characterized by more severe HF and higher CV event-rates in both scenarios, and higher comorbidity burden in the pragmatic scenario. CONCLUSION: Approximately 21% of real-world chronic HFrEF patients would be eligible for OM according to the GALACTIC-HF selection criteria, and 36% according to the criteria more likely to affect OM use in clinical practice. Criteria in both scenarios identified a patient-group with severe HF and high CV event-rates.


Asunto(s)
Insuficiencia Cardíaca , Sistema de Registros , Volumen Sistólico , Humanos , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/epidemiología , Suecia/epidemiología , Masculino , Femenino , Anciano , Persona de Mediana Edad , Volumen Sistólico/efectos de los fármacos , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Urea/análogos & derivados , Urea/sangre , Urea/uso terapéutico , Determinación de la Elegibilidad , Selección de Paciente , Anciano de 80 o más Años
9.
Plant Physiol Biochem ; 211: 108666, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723490

RESUMEN

Nitrogen (N) is the nutrient most applied in agriculture as fertilizer (as nitrate, Nit; ammonium, A; and/or urea, U, forms) and its availability strongly constrains the crop growth and yield. To investigate the early response (24 h) of N-deficient tomato plants to these three N forms, a physiological and molecular study was performed. In comparison to N-deficient plants, significant changes in the transcriptional, metabolomic and ionomic profiles were observed. As a probable consequence of N mobility in plants, a wide metabolic modulation occurred in old leaves rather than in young leaves. The metabolic profile of U and A-treated plants was more similar than Nit-treated plant profile, which in turn presented the lowest metabolic modulation with respect to N-deficient condition. Urea and A forms induced some changes at the biosynthesis of secondary metabolites, amino acids and phytohormones. Interestingly, a specific up-regulation by U and down-regulation by A of carbon synthesis occurred in roots. Along with the gene expression, data suggest that the specific N form influences the activation of metabolic pathways for its assimilation (cytosolic GS/AS and/or plastidial GS/GOGAT cycle). Urea induced an up-concentration of Cu and Mn in leaves and Zn in whole plant. This study highlights a metabolic reprogramming depending on the N form applied, and it also provide evidence of a direct relationship between urea nutrition and Zn concentration. The understanding of the metabolic pathways activated by the different N forms represents a milestone in improving the efficiency of urea fertilization in crops.


Asunto(s)
Compuestos de Amonio , Nitratos , Solanum lycopersicum , Urea , Urea/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Nitratos/metabolismo , Compuestos de Amonio/metabolismo , Hojas de la Planta/metabolismo , Metabolómica , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Metaboloma , Fertilizantes , Nitrógeno/metabolismo
10.
J Am Chem Soc ; 146(19): 12919-12924, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38691627

RESUMEN

RNA is a key biochemical marker, yet its chemical instability and complex secondary structure hamper its integration into DNA nanotechnology-based sensing platforms. Relying on the denaturation of the native RNA structure using urea, we show that restructured DNA/RNA hybrids can readily be prepared at room temperature. Using solid-state nanopore sensing, we demonstrate that the structures of our DNA/RNA hybrids conform to the design at the single-molecule level. Employing this chemical annealing procedure, we mitigate RNA self-cleavage, enabling the direct detection of restructured RNA molecules for biosensing applications.


Asunto(s)
ADN , Nanoporos , ARN , ARN/química , ARN/análisis , ADN/química , Técnicas Biosensibles/métodos , Conformación de Ácido Nucleico , Hibridación de Ácido Nucleico , Nanotecnología/métodos , Urea/química
11.
Bioorg Chem ; 147: 107403, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38691909

RESUMEN

A novel series of pyrazole derivatives with urea/thiourea scaffolds 16a-l as hybrid sorafenib/erlotinib/celecoxib analogs was designed, synthesized and tested for its VEGFR-2, EGFRWT, EGFRT790M tyrosine kinases and COX-2, pro-inflammatory cytokines TNF-α and IL-6 inhibitory activities. All the tested compounds showed excellent COX-2 selectivity index in range of 18.04-47.87 compared to celecoxib (S.I. = 26.17) and TNF-α and IL-6 inhibitory activities (IC50 = 5.0-7.50, 6.23-8.93 respectively, compared to celecoxib IC50 = 8.40 and 8.50, respectively). Screening was carried out against 60 human cancer cell lines by National Cancer Institute (NCI), compounds 16a, 16c, 16d and 16 g were the most potent inhibitors with GI% ranges of 100 %, 99.63-87.02 %, 98.98-43.10 % and 98.68-23.62 % respectively, and with GI50 values of 1.76-15.50 µM, 1.60-5.38 µM, 1.68-7.39 µM and 1.81-11.0 µM respectively, in addition, of showing good safety profile against normal cell line (F180). Moreover, compounds 16a, 16c, 16d and 16 g had cell cycle arrest at G2/M phase with induced necrotic percentage compared to sorafenib of 2.06 %, 2.47 %, 1.57 %, 0.88 % and 1.83 % respectively. Amusingly, compounds 16a, 16c, 16d and 16 g inhibited VEGFR-2 with IC50 of 25 nM, 52 nM, 324 nM and 110 nM respectively, compared to sorafenib (IC50 = 85 nM), and had excellent EGFRWT and EGFRT790M kinase inhibitory activities (IC50 = 94 nM, 128 nM, 160 nM, 297 nM), (10 nM, 25 nM, 36 nM and 48 nM) respectively, compared to both erlotinib and osimertinib (IC50 = 114 nM, 56 nM) and (70 nM, 37 nM) respectively and showed (EGFRwt/EGFRT790M S.I.) of (range: 4.44-9.40) compared to erlotinib (2.03) and osmertinib (1.89).


Asunto(s)
Antineoplásicos , Proliferación Celular , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB , Inhibidores de Proteínas Quinasas , Pirazoles , Tiourea , Urea , Receptor 2 de Factores de Crecimiento Endotelial Vascular , Humanos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Pirazoles/química , Pirazoles/farmacología , Pirazoles/síntesis química , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Tiourea/farmacología , Tiourea/química , Tiourea/síntesis química , Estructura Molecular , Urea/farmacología , Urea/química , Urea/análogos & derivados , Inhibidores de la Ciclooxigenasa 2/farmacología , Inhibidores de la Ciclooxigenasa 2/química , Inhibidores de la Ciclooxigenasa 2/síntesis química , Línea Celular Tumoral , Ciclooxigenasa 2/metabolismo , Descubrimiento de Drogas , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/síntesis química
12.
Plant Sci ; 344: 112108, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38705480

RESUMEN

Ureides, the degraded products of purine catabolism in Arabidopsis, have been shown to act as antioxidant and nitrogen sources. Herein we elucidate purine degraded metabolites as a carbon source using the Arabidopsis Atxdh1, Ataln, and Ataah knockout (KO) mutants vis-à-vis wild-type (WT) plants. Plants were grown under short-day conditions on agar plates containing half-strength MS medium with or without 1% sucrose. Notably, the absence of sucrose led to diminished biomass accumulation in both shoot and root tissues of the Atxdh1, Ataln, and Ataah mutants, while no such effect was observed in WT plants. Moreover, the application of sucrose resulted in a reduction of purine degradation metabolite levels, specifically xanthine and allantoin, predominantly within the roots of WT plants. Remarkably, an increase in proteins associated with the purine degradation pathway was observed in WT plants in the presence of sucrose. Lower glyoxylate levels in the roots but not in the shoot of the Atxdh1 mutant in comparison to WT, were observed under sucrose limitation, and improved by sucrose application in root, indicating that purine degradation provided glyoxylate in the root. Furthermore, the deficit of purine-degraded metabolites in the roots of mutants subjected to carbon starvation was partially mitigated through allantoin application. Collectively, these findings signify that under conditions of sucrose limitation and short-day growth, purines are primarily remobilized within the root system to augment the availability of ureides, serving as an additional carbon (as well as nitrogen) source to support plant growth.


Asunto(s)
Arabidopsis , Carbono , Raíces de Plantas , Sacarosa , Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Carbono/metabolismo , Sacarosa/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Alantoína/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Purinas/metabolismo , Urea/metabolismo , Brotes de la Planta/metabolismo , Brotes de la Planta/crecimiento & desarrollo , Glioxilatos/metabolismo
13.
Int J Mol Sci ; 25(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38791418

RESUMEN

In a screen of over 200 novel pyrazole compounds, ethyl 1-(2-hydroxypentyl)-5-(3-(3-(trifluoromethyl) phenyl)ureido)-1H-pyrazole-4-carboxylate (named GeGe-3) has emerged as a potential anticancer compound. GeGe-3 displays potent anti-angiogenic properties through the presumptive targeting of the protein kinase DMPK1 and the Ca2+-binding protein calreticulin. We further explored the anticancer potential of GeGe-3 on a range of established cancer cell lines, including PC3 (prostate adenocarcinoma), SKMEL-28 (cutaneous melanoma), SKOV-3 (ovarian adenocarcinoma), Hep-G2 (hepatocellular carcinoma), MDA-MB231, SKBR3, MCF7 (breast adenocarcinoma), A549 (lung carcinoma), and HeLa (cervix epithelioid carcinoma). At concentrations in the range of 10 µM, GeGe-3 significantly restricted cell proliferation and metabolism. GeGe-3 also reduced PC3 cell migration in a standard wound closure and trans-well assay. Together, these results confirm the anticancer potential of GeGe-3 and underline the need for more detailed pre-clinical investigations into its molecular targets and mechanisms of action.


Asunto(s)
Antineoplásicos , Movimiento Celular , Proliferación Celular , Pirazoles , Humanos , Pirazoles/farmacología , Pirazoles/química , Antineoplásicos/farmacología , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Urea/farmacología , Urea/química , Urea/análogos & derivados
14.
Int J Biol Macromol ; 269(Pt 1): 132043, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38702005

RESUMEN

Starch adhesive is a commonly used bonding glue that is sustainable, formaldehyde-free and biodegradable. However, there are obviously some problems related to its high viscosity, poor water and mildew resistance. Hence, exploring a starch-based adhesive with good properties that satisfies the requirements of wood processing presents the context of the current research. Thus, corn starch was used as raw material to form oxidized starch (OCS) via oxidation using sodium periodate, it was reacted with a synthesis polyurea compound that prepared from hexanediamine-urea (HU) obtained by deamination to yield a oxidized starch-hexanediamine-urea adhesive (denoted hereafter as OCSHU). The oxidation process was optimized in terms of oxidant concentration, reaction time and temperature. Furthermore, the impact of HU addition on the mechanical properties of the adhesive was explored. Results indicate adhesive exhibited outstanding shear strength, when 13 % of NaIO4 was used as an oxidant to treat starch at 55 °C for 24 h, and involved in a subsequent reaction with 40 % of HU. The dry shear strength, 24 h cold water strength, 3 h hot water strength and 3 h boiling water strength are 1.84, 1.50, 1.32, and 1.31 MPa. Meantime, OCSHU adhesive solution revealed good storage stability whereas cured resin exhibited mildew resistance. The developed adhesive is a simple and green biomass wood adhesive.


Asunto(s)
Adhesivos , Almidón , Agua , Zea mays , Almidón/química , Agua/química , Adhesivos/química , Zea mays/química , Oxidación-Reducción , Temperatura , Resistencia al Corte , Urea/química
15.
Water Res ; 257: 121751, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38744062

RESUMEN

The human urine metabolome is complex, containing a wide range of organic metabolites that affect treatment of urine collected in resource-oriented sanitation systems. In this study, an advanced oxidation process involving heat-activated peroxydisulphate was used to selectively oxidise organic metabolites in urine over urea and chloride. Initial experiments evaluated optimal conditions (peroxydisulphate dose, temperature, time, pH) for activation of peroxydisulphate in unconcentrated, non-hydrolysed synthetic urine and real urine acidified to pH 3.0. Subsequent experiments determined the fate of 268 endogenous organic metabolites (OMs) and removal of COD from unconcentrated and concentrated real urine (80-90% mass reduced by evaporation). The results revealed >90% activation of 60 mM peroxydisulphate in real unconcentrated urine heated to 90 °C for 1 h, resulting in 43% ΣOMs degradation, 22% COD removal and 56% total organic carbon removal, while >94% of total nitrogen and >97% of urea in real unconcentrated urine were recovered. The mechanism of urea degradation was identified to be chemical hydrolysis to ammonia, with the rate constant for this reaction determined to be 1.9 × 10-6 s-1 at pH 3.0 and 90 °C. Treating concentrated real urine resulted in similar removal of COD, ΣOMs degradation and total nitrogen loss as observed for unconcentrated urine, but with significantly higher chloride oxidation and chemical hydrolysis of urea. Targeted metabolomic analysis revealed that peroxydisulphate treatment degraded 157 organic metabolites in urine, of which 67 metabolites were degraded by >80%. The rate constant for the reaction of sulphate radicals with oxidisable endogenous organic metabolites in urine was estimated to exceed 108 M-1 s-1. These metabolites were preferentially oxidised over chloride and urea in acidified, non-hydrolysed urine treated with peroxydisulphate. Overall, the findings support the development of emerging urine recycling technologies, including alkaline/acid dehydration and reverse osmosis, where the presence of endogenous organic urine metabolites significantly influences treatment parameters such as energy demand and product purity.


Asunto(s)
Oxidación-Reducción , Orina , Humanos , Orina/química , Sulfatos/metabolismo , Sulfatos/química , Sulfatos/orina , Concentración de Iones de Hidrógeno , Urea/metabolismo , Urea/orina
16.
Braz J Biol ; 84: e279269, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38808785

RESUMEN

Among the factors that increase the efficiency of mineral fertilizers, due consideration has lately been given to the development and study of fertilizers with various granule coatings. This study is focused on the test of urea and NPK fertilizers, with granules coated with 50 and 100 µm monocalcium phosphate. Two-year greenhouse trials with spring wheat were carried out on soddy-podzolic light loamy soil. Coated fertilizers have proven to be more effective than traditional ones. For instance, using coated urea improved the yield 10-11% compared to conventional fertilizer. At the same time, the weight of one plant increased by 9-11% and the weight of the ear by 10%, the number of grains in the ear was by 4-7% bigger. Similar results were obtained with NPK fertilizer. Providing a thicker coating from 50 to 100 µm significantly increased the efficiency of both urea and NPK fertilizers.


Asunto(s)
Fertilizantes , Nitrógeno , Triticum , Urea , Fertilizantes/análisis , Triticum/crecimiento & desarrollo , Urea/farmacología , Estaciones del Año , Biomasa
17.
Water Sci Technol ; 89(6): 1454-1465, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38557711

RESUMEN

We used bench-scale tests and mathematical modeling to explore chemical oxygen demand (COD) removal rates in a moving-bed biofilm reactor (MBBR) for winery wastewater treatment, using either urea or nitrate as a nitrogen source. With urea addition, the COD removal fluxes ranged from 34 to 45 gCOD/m2-d. However, when nitrate was added, fluxes increased up to 65 gCOD/m2-d, twice the amount reported for aerobic biofilms for winery wastewater treatment. A one-dimensional biofilm model, calibrated with data from respirometric tests, accurately captured the experimental results. Both experimental and modelling results suggest that nitrate significantly increased MBBR capacity by stimulating COD oxidation in the deeper, oxygen-limited regions of the biofilm. Our research suggests that the addition of nitrate, or other energetic and broadly used electron acceptors, may provide a cost-effective means of covering peak COD loads in biofilm processes for winery or another industrial wastewater treatment.


Asunto(s)
Eliminación de Residuos Líquidos , Purificación del Agua , Eliminación de Residuos Líquidos/métodos , Nitratos , Biopelículas , Reactores Biológicos , Compuestos Orgánicos , Purificación del Agua/métodos , Nitrógeno , Urea , Desnitrificación
18.
Open Vet J ; 14(1): 500-511, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38633158

RESUMEN

Background: One of the most challenging pests to control is the wild rat (Rattus norvegicus), which poses serious risks to both human health and the economy. Fertilizers are a more recent method of pest management with various action modes and are considered safe control agents when applied at low doses. Aim: The present study aimed to examine the toxicological impacts of the contaminated water with urea and camphor oil individually, post-treatment of rats with camphor oil after the pre-treatment with urea and post-treatment of rats with urea mixed with camphor oil after urea pre-treatment against the wild rats (R. norvegicus). Methods: The study extends to explore the influence of these treatments on the physicochemical parameters of the water administered by rats. Moreover, the effect of the most three toxic treatments was studied on the blood and renal functional parameters and the kidney tissue of rats after 21 days of treatment. Results: The study showed that urea was more potent than camphor oil when applied individually and increasing the concentration of urea in the pre-treatment or when combined with camphor oil in the post-treatment caused a significant increase in the mortality of rats. The post-treatment of rats with camphor oil only or camphor oil mixed with urea after the pre-treatment with urea induced a synergistic activity against rats. In addition, the exposed water to urea and camphor oil has been modified in physicochemical parameters and formed ulcers and harm to the kidneys of the exposed wild rats. Conclusion: This study significantly contributes to the ecological and toxicological potential risk indexes of urea and camphor oil together, which are restricted on the perceptible value relevance in the literature of water quality and renal pathology. Therefore, urea and camphor oil represent successful agents for the wild rat's control.


Asunto(s)
Alcanfor , Urea , Ratas , Animales , Humanos
19.
ACS Appl Mater Interfaces ; 16(15): 19480-19495, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38581369

RESUMEN

Light-driven soft actuators based on photoresponsive materials can be used to mimic biological motion, such as hand movements, without involving rigid or bulky electromechanical actuations. However, to our knowledge, no robust photoresponsive material with desireable mechanical and biological properties and relatively simple manufacture exists for robotics and biomedical applications. Herein, we report a new visible-light-responsive thermoplastic elastomer synthesized by introducing photoswitchable moieties (i.e., azobenzene derivatives) into the main chain of poly(ε-caprolactone) based polyurethane urea (PAzo). A PAzo elastomer exhibits controllable light-driven stiffness softening due to its unique nanophase structure in response to light, while possessing excellent hyperelasticity (stretchability of 575.2%, elastic modulus of 17.6 MPa, and strength of 44.0 MPa). A bilayer actuator consisting of PAzo and polyimide films is developed, demonstrating tunable bending modes by varying incident light intensities. Actuation mechanism via photothermal and photochemical coupling effects of a soft-hard nanophase is demonstrated through both experimental and theoretical analyses. We demonstrate an exemplar application of visible-light-controlled soft "fingers" playing a piano on a smartphone. The robustness of the PAzo elastomer and its scalability, in addition to its excellent biocompatibility, opens the door to the development of reproducible light-driven wearable/implantable actuators and lightweight soft robots for clinical applications.


Asunto(s)
Elastómeros , Robótica , Elastómeros/química , Poliuretanos , Urea
20.
J Am Chem Soc ; 146(17): 11592-11598, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38630123

RESUMEN

Cocrystal screening and single-crystal growth remain the primary obstacles in the development of pharmaceutical cocrystals. Here, we present a new approach for cocrystal screening, microspacing in-air sublimation (MAS), to obtain new cocrystals and grow high-quality single crystals of cocrystals within tens of minutes. The method possesses the advantages of strong designable ability of devices, user-friendly control, and compatibility with materials, especially for the thermolabile molecules. A novel drug-drug cocrystal of favipiravir (FPV) with salicylamide (SAA) was first discovered by this method, which shows improved physiochemical properties. Furthermore, this method proved effective in cultivating single crystals of FPV-isonicotinamide (FPV-INIA), FPV-urea, FPV-nicotinamide (FPV-NIA), and FPV-tromethamine (FPV-Tro) cocrystals, and the structures of these cocrystals were determined for the first time. By adjusting the growth temperature and growth distance precisely, we also achieved single crystals of 10 different paracetamol (PCA) cocrystals and piracetam (PIR) cocrystals, which underscores the versatility and efficiency of this method in pharmaceutical cocrystal screening.


Asunto(s)
Amidas , Cristalización , Niacinamida , Pirazinas , Niacinamida/química , Pirazinas/química , Amidas/química , Salicilamidas/química , Urea/química , Modelos Moleculares , Cristalografía por Rayos X
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