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1.
Xenobiotica ; 52(8): 786-796, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36537234

RESUMEN

Paxlovid, a drug combining nirmatrelvir and ritonavir, was designed for the treatment of COVID-19 and its rapid development has led to emergency use approval by the FDA to reduce the impact of COVID-19 infection on patients.In order to overcome potentially suboptimal therapeutic exposures, nirmatrelvir is dosed in combination with ritonavir to boost the pharmacokinetics of the active product.Here we consider examples of drugs co-administered with pharmacoenhancers.Pharmacoenhancers have been adopted for multiple purposes such as ensuring therapeutic exposure of the active product, reducing formation of toxic metabolites, changing the route of administration, and increasing the cost-effectiveness of a therapy.We weigh the benefits and risks of this approach, examining the impact of technology developments on drug design and how enhanced integration between cross-discipline teams can improve the outcome of drug discovery.


Asunto(s)
COVID-19 , Descubrimiento de Drogas , Ritonavir , Humanos , Industria Farmacéutica , Proteína Quinasa de Distrofia Miotónica
2.
Environ Monit Assess ; 193(12): 780, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34748090

RESUMEN

This study aims to determine the concentration of potentially toxic elements (PTEs) and rare earth elements (REEs) in Brazilian sandy soils under the Cerrado at the Parnaíba-São Francisco Basin transition. We also explored the geochemical correlation between these elements and pH, cation exchange capacity (CEC), total organic carbon (TOC), sand, clay, oxides from secondary minerals, and chemical index of alteration for each basin. Mineralogical, physical, and chemical analyses were used to examine PTE and REE geochemistry in six sand soil profiles from the Brazilian Cerrado. The background concentrations of these elements are low, but soils from the Parnaíba Basin have higher concentrations of PTEs than soils from the São Francisco Basin. In soils from the Parnaíba Basin, mainly Al2O3 has relevance in the V and Cr geochemistry, as these elements increase with increasing Al2O3 content. On the other hand, the REEs have CEC as a soil attribute of higher relevance in the geochemistry of those elements is soils from the Parnaíba Basin, and this relevance divides the TOC, Fe2O3, and TiO2 minerals from the clay fraction. In soils from the São Francisco Basin, the geochemistry of PTEs is possibly associated with kaolinite, especially Cu, V, and Zn. In contrast, the Ba concentration was associated with the presence of feldspar. Unlike soils from the Parnaíba Basin, the REEs do not correlate with the studied soil attributes, except for Ho and Lu. Ho had a positive association with Al2O3. Ho and Lu are negatively related to the presence of iron oxides.


Asunto(s)
Metales de Tierras Raras , Contaminantes del Suelo , Monitoreo del Ambiente , Metales de Tierras Raras/análisis , Arena , Suelo , Contaminantes del Suelo/análisis
3.
Am J Respir Cell Mol Biol ; 63(5): 571-590, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32640172

RESUMEN

PARP1, the major isoform of a family of ADP-ribosylating enzymes, has been implicated in the regulation of various biological processes including DNA repair, gene transcription, and cell death. The concept that PARP1 becomes activated in acute lung injury (ALI) and that pharmacological inhibition or genetic deletion of this enzyme can provide therapeutic benefits emerged over 20 years ago. The current article provides an overview of the cellular mechanisms involved in the pathogenetic roles of PARP1 in ALI and provides an overview of the preclinical data supporting the efficacy of PARP (poly[ADP-ribose] polymerase) inhibitors. In recent years, several ultrapotent PARP inhibitors have been approved for clinical use (for the therapy of various oncological diseases): these newly-approved PARP inhibitors were recently reported to show efficacy in animal models of ALI. These observations offer the possibility of therapeutic repurposing of these inhibitors for patients with ALI. The current article lays out a potential roadmap for such repurposing efforts. In addition, the article also overviews the scientific basis of potentially applying PARP inhibitors for the experimental therapy of viral ALI, such as coronavirus disease (COVID-19)-associated ALI.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Antivirales/uso terapéutico , Betacoronavirus/efectos de los fármacos , Infecciones por Coronavirus/tratamiento farmacológico , Pulmón/efectos de los fármacos , Neumonía Viral/tratamiento farmacológico , Poli(ADP-Ribosa) Polimerasa-1/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Lesión Pulmonar Aguda/enzimología , Lesión Pulmonar Aguda/virología , Animales , Antivirales/efectos adversos , Betacoronavirus/patogenicidad , COVID-19 , Infecciones por Coronavirus/enzimología , Infecciones por Coronavirus/virología , Interacciones Huésped-Patógeno , Humanos , Pulmón/enzimología , Pulmón/virología , Pandemias , Neumonía Viral/enzimología , Neumonía Viral/virología , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/efectos adversos , SARS-CoV-2 , Transducción de Señal/efectos de los fármacos , Tratamiento Farmacológico de COVID-19
4.
Environ Monit Assess ; 192(4): 254, 2020 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-32222881

RESUMEN

The Cerrado soil is under constant modification, especially because of the use of agricultural systems, which affect soil carbon (C) and phosphorus (P) functioning. Thus, the objective of this study was to determine the C and P dynamics in Brazilian Cerrado Oxisol in Piauí State under natural and anthropic conditions, considering that conservational agricultural management and no-tillage systems can restore the C and P pools in that soil. Four soil samples with distinct characteristics (native Cerrado, NC; burned native Cerrado, BNC; conventional tillage agricultural system, CTS; and no-tillage agricultural system, NTS) were collected in the study area for chemical and physical laboratory analysis. The total organic carbon (TOC) concentrations found were 33 g kg-1, 27 g kg-1, 26 g kg-1, and 20 g kg-1 for CTS, NTS, NC, and BNC, respectively. The NTS had a total nitrogen (TN) concentration of 2.0 g kg-1. The CTS had 33.4 g kg-1 of soil-oxidizable C, followed by the NTS with 27.2 g kg-1. In both studied layers, the NTS had an organic P concentration > 200 mg kg-1. The higher TOC concentration in the CTS was because of the higher content of clay in comparison with that in the NTS. The organic P in the NTS was associated with a less labile fraction of C. Thus, despite the disturbance caused by agricultural systems, the adoption of the NTS could be an influential strategy in agricultural systems to restore soil organic functioning in the Brazilian Cerrado Oxisol in Piauí State.


Asunto(s)
Agricultura/métodos , Suelo , Brasil , Carbono/análisis , Monitoreo del Ambiente , Fósforo/análisis
5.
Anesthesiology ; 128(6): 1193-1206, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29489470

RESUMEN

BACKGROUND: The authors hypothesized that low tidal volume (VT) would minimize ventilator-induced lung injury regardless of the degree of mechanical power. The authors investigated the impact of power, obtained by different combinations of VT and respiratory rate (RR), on ventilator-induced lung injury in experimental mild acute respiratory distress syndrome (ARDS). METHODS: Forty Wistar rats received Escherichia coli lipopolysaccharide intratracheally. After 24 h, 32 rats were randomly assigned to be mechanically ventilated (2 h) with a combination of different VT (6 ml/kg and 11 ml/kg) and RR that resulted in low and high power. Power was calculated as energy (ΔP,L/E,L) × RR (ΔP,L = transpulmonary driving pressure; E,L = lung elastance), and was threefold higher in high than in low power groups. Eight rats were not mechanically ventilated and used for molecular biology analysis. RESULTS: Diffuse alveolar damage score, which represents the severity of edema, atelectasis, and overdistension, was increased in high VT compared to low VT, in both low (low VT: 11 [9 to 14], high VT: 18 [15 to 20]) and high (low VT: 19 [16 to 25], high VT: 29 [27 to 30]) power groups. At high VT, interleukin-6 and amphiregulin expressions were higher in high-power than in low-power groups. At high power, amphiregulin and club cell protein 16 expressions were higher in high VT than in low VT. Mechanical energy and power correlated well with diffuse alveolar damage score and interleukin-6, amphiregulin, and club cell protein 16 expression. CONCLUSIONS: In experimental mild ARDS, even at low VT, high mechanical power promoted ventilator-induced lung injury. To minimize ventilator-induced lung injury, low VT should be combined with low power.


Asunto(s)
Síndrome de Dificultad Respiratoria/fisiopatología , Mecánica Respiratoria/fisiología , Mucosa Respiratoria/fisiopatología , Volumen de Ventilación Pulmonar/fisiología , Animales , Distribución Aleatoria , Ratas , Ratas Wistar , Síndrome de Dificultad Respiratoria/patología , Mucosa Respiratoria/patología
6.
Am J Pathol ; 185(10): 2768-76, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26261086

RESUMEN

Subcutaneous lipoatrophy characteristically accompanies dermal fibrosis with de novo emergence of myofibroblasts such as in systemic sclerosis or scleroderma. Recently dermal adipocytes were shown to have the capacity to differentiate to myofibroblasts in an animal model. Transforming growth factor ß can induce this phenomenon in vitro; however its in vivo significance is unclear. Because found in inflammatory zone 1 (FIZZ1) is an inducer of myofibroblast differentiation but an inhibitor of adipocyte differentiation, we investigated its potential role in adipocyte transdifferentiation to myofibroblast in dermal fibrosis. FIZZ1 caused significant and rapid suppression of the expression of fatty acid binding protein 4 and peroxisome proliferator-activated receptor-γ in adipocytes, consistent with dedifferentiation with loss of lipid and Oil Red O staining. The suppression was accompanied subsequently with stimulation of α-smooth muscle actin and type I collagen expression, indicative of myofibroblast differentiation. In vivo FIZZ1 expression was significantly elevated in the murine bleomycin-induced dermal fibrosis model, which was associated with significant reduction in adipocyte marker gene expression and subcutaneous lipoatrophy. Finally, FIZZ1 knockout mice exhibited significantly reduced bleomycin-induced dermal fibrosis with greater preservation of the subcutaneous fat than wild-type mice. These findings suggested that the FIZZ1 induction of adipocyte transdifferentiation to myofibroblast might be a key pathogenic mechanism for the accumulation of myofibroblasts in dermal fibrosis.


Asunto(s)
Diferenciación Celular/fisiología , Transdiferenciación Celular/fisiología , Fibroblastos/citología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Lipodistrofia/metabolismo , Miofibroblastos/patología , Adipocitos/patología , Animales , Fibrosis/metabolismo , Lipodistrofia/patología , Ratones Endogámicos C57BL , Enfermedades de la Piel/metabolismo , Enfermedades de la Piel/patología
7.
Respir Res ; 17(1): 158, 2016 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-27887604

RESUMEN

BACKGROUND: Variable ventilation has been shown to improve pulmonary function and reduce lung damage in different models of acute respiratory distress syndrome. Nevertheless, variable ventilation has not been tested during pneumonia. Theoretically, periodic increases in tidal volume (VT) and airway pressures might worsen the impairment of alveolar barrier function usually seen in pneumonia and could increase bacterial translocation into the bloodstream. We investigated the impact of variable ventilation on lung function and histologic damage, as well as markers of lung inflammation, epithelial and endothelial cell damage, and alveolar stress, and bacterial translocation in experimental pneumonia. METHODS: Thirty-two Wistar rats were randomly assigned to receive intratracheal of Pseudomonas aeruginosa (PA) or saline (SAL) (n = 16/group). After 24-h, animals were anesthetized and ventilated for 2 h with either conventional volume-controlled (VCV) or variable volume-controlled ventilation (VV), with mean VT = 6 mL/kg, PEEP = 5cmH2O, and FiO2 = 0.4. During VV, tidal volume varied randomly with a coefficient of variation of 30% and a Gaussian distribution. Additional animals assigned to receive either PA or SAL (n = 8/group) were not ventilated (NV) to serve as controls. RESULTS: In both SAL and PA, VV improved oxygenation and lung elastance compared to VCV. In SAL, VV decreased interleukin (IL)-6 expression compared to VCV (median [interquartile range]: 1.3 [0.3-2.3] vs. 5.3 [3.6-7.0]; p = 0.02) and increased surfactant protein-D expression compared to NV (2.5 [1.9-3.5] vs. 1.2 [0.8-1.2]; p = 0.0005). In PA, compared to VCV, VV reduced perivascular edema (2.5 [2.0-3.75] vs. 6.0 [4.5-6.0]; p < 0.0001), septum neutrophils (2.0 [1.0-4.0] vs. 5.0 [3.3-6.0]; p = 0.0008), necrotizing vasculitis (3.0 [2.0-5.5] vs. 6.0 [6.0-6.0]; p = 0.0003), and ultrastructural lung damage scores (16 [14-17] vs. 24 [14-27], p < 0.0001). Blood colony-forming-unit (CFU) counts were comparable (7 [0-28] vs. 6 [0-26], p = 0.77). Compared to NV, VCV, but not VV, increased expression amphiregulin, IL-6, and cytokine-induced neutrophil chemoattractant (CINC)-1 (2.1 [1.6-2.5] vs. 0.9 [0.7-1.2], p = 0.025; 12.3 [7.9-22.0] vs. 0.8 [0.6-1.9], p = 0.006; and 4.4 [2.9-5.6] vs. 0.9 [0.8-1.4], p = 0.003, respectively). Angiopoietin-2 expression was lower in VV compared to NV animals (0.5 [0.3-0.8] vs. 1.3 [1.0-1.5], p = 0.01). CONCLUSION: In this rat model of pneumonia, VV improved pulmonary function and reduced lung damage as compared to VCV, without increasing bacterial translocation.


Asunto(s)
Traslocación Bacteriana , Pulmón/fisiopatología , Neumonía Bacteriana/terapia , Infecciones por Pseudomonas/terapia , Respiración Artificial/métodos , Algoritmos , Animales , Células Endoteliales/patología , Células Epiteliales/patología , Inflamación/patología , Pulmón/ultraestructura , Neumonía Bacteriana/microbiología , Neumonía Bacteriana/fisiopatología , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/fisiopatología , Alveolos Pulmonares/patología , Ratas , Ratas Wistar , Pruebas de Función Respiratoria , Volumen de Ventilación Pulmonar
8.
BMC Palliat Care ; 15: 51, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-27251335

RESUMEN

BACKGROUND: The Brazilian healthcare system offers universal coverage but lacks information about how patients with PC needs are serviced by its primary care program, Estratégia Saúde da Família (ESF). METHODS: Cross-sectional study in community settings. Patients in ESF program were screened using a Palliative Care Screening Tool (PCST). Included patients were assessed with Karnofsky Performance Scale (KPS), Edmonton Symptom Assessment System (ESAS) and Palliative Care Outcome Scale (POS). RESULTS: Patients with PC needs are accessing the ESF program regardless of there being no specific PC support provided. From 238 patients identified, 73 (43 women, 30 men) were identified as having a need for PC, and the mean age was 77.18 (95 % Confidence Interval = ±2,78) years, with non-malignant neurologic conditions, such as dementia and cerebrovascular diseases, being the most common (53 % of all patients). Chronic conditions (2 or more years) were found in 70 % of these patients, with 71 % scoring 50 or less points in the KPS. Overall symptom intensity was low, with the exception of some cases with moderate and high score, and POS average score was 14.16 points (minimum = 4; maximum = 28). Most patients received medication and professional support through the primary care units, but limitations of services were identified, including lack of home visits and limited multi-professional approaches. CONCLUSION: Patients with PC needs were identified in ESF program. Basic health care support is provided but there is a lack of attention to some specific needs. PC policies and professional training should be implemented to improve this area.


Asunto(s)
Cuidados Paliativos/organización & administración , Cuidados Paliativos/estadística & datos numéricos , Atención Primaria de Salud/organización & administración , Atención Primaria de Salud/estadística & datos numéricos , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Ansiedad/epidemiología , Brasil , Estudios Transversales , Depresión/epidemiología , Femenino , Humanos , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Limitación de la Movilidad , Programas Nacionales de Salud/organización & administración , Programas Nacionales de Salud/estadística & datos numéricos , Evaluación de Necesidades , Dolor/epidemiología , Comodidad del Paciente/organización & administración , Comodidad del Paciente/estadística & datos numéricos , Educación del Paciente como Asunto/organización & administración , Distribución por Sexo , Factores Socioeconómicos , Factores de Tiempo
9.
Homeopathy ; 105(3): 250-256, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27473546

RESUMEN

BACKGROUND: As a therapeutic system, homeopathy is supported by: i) similitude and experimentation in healthy individuals, ii) potentization. A challenge for researchers consists in looking for signals in water (or vehicle) to explain the storage of information in extremely high dilutions and the transfer of such information to the living systems. Anuran amphibian metamorphosis is controlled by thyroid hormones (TH), including the resorption of the tadpole tail. Apoptosis is a genetically regulated form of cell death that can be triggered by various extracellular and intracellular stimuli resulting in coordinated activation of a family of cysteine proteases called caspases. METHODS: This study was blind and randomized. It performed in three stages: I) the identification of the most effective T3 homeopathic dilution to induce apoptotic reactions in Rana (Lithobates) catesbeianus tadpole tail explants stimulated by T3 in substantial, II) study of different controls and III) detection in explants under the action of the most effective dilution of T3, as established in Stage I. RESULTS: There was no statistically significant difference between tail macroscopic dimensions between the groups. T3 10cH decreased the expression of caspase 3/7 mRNA, in explants treated with T3 20 nM. CONCLUSION: The present experiment is in agreement with the hypothesis that T3, at a 10cH homeopathic dilution, changes the metamorphosis molecular network.


Asunto(s)
Apoptosis/efectos de los fármacos , Larva/efectos de los fármacos , Materia Medica/química , Metamorfosis Biológica/efectos de los fármacos , Triyodotironina/farmacología , Animales , Homeopatía , Técnicas de Cultivo de Órganos , Rana catesbeiana , Cola (estructura animal)/efectos de los fármacos
10.
Proc Natl Acad Sci U S A ; 109(20): E1267-76, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22529373

RESUMEN

We have previously demonstrated an increased DNA copy number and expression of IGF1R to be associated with poor outcome in Wilms tumors. We have now tested whether inhibiting this receptor may be a useful therapeutic strategy by using a panel of Wilms tumor cell lines. Both genetic and pharmacological targeting resulted in inhibition of downstream signaling through PI3 and MAP kinases, G(1) cell cycle arrest, and cell death, with drug efficacy dependent on the levels of phosphorylated IGF1R. These effects were further associated with specific gene expression signatures reflecting pathway inhibition, and conferred synergistic chemosensitisation to doxorubicin and topotecan. In the in vivo setting, s.c. xenografts of WiT49 cells resembled malignant rhabdoid tumors rather than Wilms tumors. Treatment with an IGF1R inhibitor (NVP-AEW541) showed no discernable antitumor activity and no downstream pathway inactivation. By contrast, Wilms tumor cells established orthotopically within the kidney were histologically accurate and exhibited significantly elevated insulin-like growth factor-mediated signaling, and growth was significantly reduced on treatment with NVP-AEW541 in parallel with signaling pathway ablation. As a result of the paracrine effects of enhanced IGF2 expression in Wilms tumor, this disease may be acutely dependent on signaling through the IGF1 receptor, and thus treatment strategies aimed at its inhibition may be useful in the clinic. Such efficacy may be missed if only standard ectopic models are considered as a result of an imperfect recapitulation of the specific tumor microenvironment.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Neoplasias Renales/fisiopatología , Transducción de Señal/fisiología , Tumor de Wilms/fisiopatología , Análisis de Varianza , Animales , Línea Celular Tumoral , Electroquímica , Perfilación de la Expresión Génica , Células HEK293 , Humanos , Imagen por Resonancia Magnética , Ratones , Comunicación Paracrina/fisiología , Fosforilación , Pirimidinas/farmacología , Pirroles/farmacología , Receptor IGF Tipo 1/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Trasplante Heterólogo
11.
Int J Environ Health Res ; 24(5): 450-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24256564

RESUMEN

In this study, the prevalence and risk factors for enteroparasites were determined in food handlers from Maringá, Paraná State, southern Brazil. Fecal and subungual materials of 150 street food vendors were analyzed by the methods of Lutz, Faust, and Mello, respectively. A questionnaire on hygiene and sanitary conditions of the workplace and of domicile was applied. The prevalence of enteroparasites was 28%, and the protozoa infection was more expressive (21.3%) than by helminths (6.7%), but without significant difference (p > 0.05). Entamoeba coli was the most frequent species occurring in 15.3%, while the prevalence of protozoa pathogenic was low (Giardia lamblia: 2.7% and Entamoeba histolytica: 0.7%). The subungual material presented negative results. The presence of pets in domiciles has increased twice the risk of infection. The working conditions of the majority of street food vendors were inappropriate. The results highlight the need for more rigorous programs of continuing education, parasitological examination every six months, and health surveillance. In this way, the quality of the service provided to the population can be improved and the transmission of food-borne diseases can be prevented.


Asunto(s)
Manipulación de Alimentos , Enfermedades Transmitidas por los Alimentos/epidemiología , Parasitosis Intestinales/epidemiología , Exposición Profesional , Adulto , Anciano , Brasil/epidemiología , Femenino , Enfermedades Transmitidas por los Alimentos/parasitología , Humanos , Parasitosis Intestinales/parasitología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Adulto Joven
12.
J Med Chem ; 67(6): 4655-4675, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38462716

RESUMEN

The ubiquitously expressed protein tyrosine phosphatase SHP2 is required for signaling downstream of receptor tyrosine kinases (RTKs) and plays a role in regulating many cellular processes. Genetic knockdown and pharmacological inhibition of SHP2 suppresses RAS/MAPK signaling and inhibit the proliferation of RTK-driven cancer cell lines. Here, we describe the first reported fragment-to-lead campaign against SHP2, where X-ray crystallography and biophysical techniques were used to identify fragments binding to multiple sites on SHP2. Structure-guided optimization, including several computational methods, led to the discovery of two structurally distinct series of SHP2 inhibitors binding to the previously reported allosteric tunnel binding site (Tunnel Site). One of these series was advanced to a low-nanomolar lead that inhibited tumor growth when dosed orally to mice bearing HCC827 xenografts. Furthermore, a third series of SHP2 inhibitors was discovered binding to a previously unreported site, lying at the interface of the C-terminal SH2 and catalytic domains.


Asunto(s)
Neoplasias , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Humanos , Ratones , Animales , Transducción de Señal , Proteínas Tirosina Quinasas Receptoras/metabolismo , Sitio Alostérico
13.
Phys Chem Chem Phys ; 15(22): 8795-804, 2013 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-23640581

RESUMEN

We study the adsorption equilibrium isotherms and differential heats of adsorption of hexane isomers on the zeolitic imidazolate framework ZIF-8. The studies are carried out at 373 K using a manometric set-up combined with a micro-calorimeter. We see that the Langmuir model describes well the isotherms for all four isomers (n-hexane, 2-methylpentane, 2,2-dimethylbutane and 2,3-dimethylbutane). The linear and mono-branched isomers adsorb well, but 2,2-dimethylbutane is totally excluded. Plotting the differential heat of adsorption against the loading shows an initial plateau for n-hexane and 2-methylpentane. This is followed by a slow rise, indicating adsorbate-adsorbate interactions. For the di-branched isomers the differential heat of adsorption decreases with loading. To gain further insight, we ran molecular simulations using the grand-canonical Monte Carlo approach. Comparing the simulation and the experimental results shows that the ZIF framework model requires blocking of the cages, since 2,2-dimethylbutane cannot fit through the sodalite-type windows. Practically speaking, this means that ZIF-8 is a highly promising candidate for enhancing gasoline octane numbers at 373 K, as it can separate 2,2-dimethylbutane and 2,3-dimethylbutane from 2-methylpentane. Our results prove the potential of ZIF-8 as a new adsorbent that can be employed in the upgrade of the Total Isomerization Process for the production of high octane number gasoline, by blending di-branched alkanes in the gasoline.


Asunto(s)
Alcanos/química , Simulación de Dinámica Molecular , Zeolitas/química , Modelos Moleculares , Método de Montecarlo
14.
Polymers (Basel) ; 15(3)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36771795

RESUMEN

The building industry needs to innovate towards a more sustainable future and can do so through a combination of more renewable material choices and less wasteful fabrication processes. To address these issues, a hybrid material and fabrication system was developed using laminated timber veneer and natural fibre-reinforced composites (NFRPs), two materials that are leveraged for their potential of strategic material placement in additive processes towards programmed material behaviour and performance. The main contribution is in the hybrid fabrication approach, using thin, bent laminated veneer as an embedded frame for coreless filament winding of NFRP, which removes the need for temporary, wasteful formwork that is typically required to achieve structurally performative bent timber or FRP elements. Integrative methods are developed for the design, simulation, and fabrication of a rocking chair prototype that illustrates the architectural potential of the developed fabrication approach.

15.
Plants (Basel) ; 12(5)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36903917

RESUMEN

Anthocyanidins are found in nature mainly as pelargonidin, cyanidin, peonidin, delphinidin, petunidin, and malvidin derivatives. These compounds are found free or as glycoside derivatives which are responsible for the color (red, blue, and violet) of some foods and are responsible for attracting seed dispersers. They are grouped into 3-hydroxyanthocyanidins, 3-deoxyanthocyanidins (3D-anth), and O-methylated anthocyanidins. A new method was developed and validated to quantify 3D-anth in plant-rich extracts. To test the new method, Arrabidaea chica Verlot was selected as it is widely used in folk medicine, and it is rich in 3D-anth. The new method was developed by HPLC-DAD and expressed 3D-anth as carajurin content. Carajurin was chosen as the reference standard due to its role as a biological marker for the antileishmanial activity for A. chica. The selected method used a silica-based phenyl column, a mobile phase composed of potassium dihydrogen phosphate buffer, acetonitrile, and methanol, in a gradient elution mode and detection at 480 nm. The method reliability was confirmed by verifying selectivity, linearity, precision, recovery, and robustness. This method contributes to quality control and development of a possible active pharmaceutical ingredient from A. chica as well as it can be used to evaluate 3D-anth in plant extracts with chemical ecology interest.

16.
Antioxidants (Basel) ; 12(3)2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36978895

RESUMEN

Cystathionine ß-synthase (CBS), CSE (cystathionine γ-lyase) and 3-mercaptopyruvate sulfurtransferase (3-MST) have emerged as three significant sources of hydrogen sulfide (H2S) in various forms of mammalian cancer. Here, we investigated the functional role of CBS' and 3-MST's catalytic activity in the murine breast cancer cell line EO771. The CBS/CSE inhibitor aminooxyacetic acid (AOAA) and the 3-MST inhibitor 2-[(4-hydroxy-6-methylpyrimidin-2-yl)sulfanyl]-1-(naphthalen-1-yl)ethan-1-one (HMPSNE) were used to assess the role of endogenous H2S in the modulation of breast cancer cell proliferation, migration, bioenergetics and viability in vitro. Methods included measurements of cell viability (MTT and LDH assays), cell proliferation and in vitro wound healing (IncuCyte) and cellular bioenergetics (Seahorse extracellular flux analysis). CBS and 3-MST, as well as expression were detected by Western blotting; H2S production was measured by the fluorescent dye AzMC. The results show that EO771 cells express CBS, CSE and 3-MST protein, as well as several enzymes involved in H2S degradation (SQR, TST, and ETHE1). Pharmacological inhibition of CBS or 3-MST inhibited H2S production, suppressed cellular bioenergetics and attenuated cell proliferation. Cell migration was only inhibited by the 3-MST inhibitor, but not the CBS/CSE inhibitor. Inhibition of CBS/CSE of 3-MST did not significantly affect basal cell viability; inhibition of 3-MST (but not of CBS/CSE) slightly enhanced the cytotoxic effects of oxidative stress (hydrogen peroxide challenge). From these findings, we conclude that endogenous H2S, generated by 3-MST and to a lower degree by CBS/CSE, significantly contributes to the maintenance of bioenergetics, proliferation and migration in murine breast cancer cells and may also exert a minor role as a cytoprotectant.

17.
Toxicol Pathol ; 40(5): 731-41, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22549973

RESUMEN

The development of bleomycin-induced pulmonary fibrosis (BLEO-PF) has been associated with differences in genetic background and oxidative stress status. The authors' aim was to investigate the crosstalk between the redox profile, lung histology, and respiratory function in BLEO-PF in C57BL/6, DBA/2, and BALB/c mice. BLEO-PF was induced with a single intratracheal dose of bleomycin (0.1 U/mouse). Twenty-one days after bleomycin administration, the mortality rate was over 50% in C57BL/6 and 20% in DBA/2 mice, and BLEO-PF was not observed in BALB/c. There was an increase in lung static elastance (p < .001), viscoelastic/inhomogeneous pressure (p < .05), total pressure drop after flow interruption (p < .01), and ΔE (p < .05) in C57BL/6 mice. The septa volume increased in C57BL/6 (p < .05) and DBA/2 (p < .001). The levels of IFN-γ were reduced in C57BL/6 mice (p < .01). OH-proline levels were increased in C57BL/6 and DBA/2 mice (p < .05). SOD activity and expression were reduced in C57BL/6 and DBA/2 mice (p < .001 and p < .001, respectively), whereas catalase was reduced in all strains 21 days following bleomycin administration compared with the saline groups (C57BL/6: p < .05; DBA/2: p < .01; BALB/c: p < .01). GPx activity and GPx1/2 expression decreased in C57BL/6 (p < .001). The authors conclude that BLEO-PF resistance may also be related to the activity and expression of SOD in BALB/c mice.


Asunto(s)
Bleomicina/efectos adversos , Estrés Oxidativo , Fibrosis Pulmonar/patología , Fenómenos Fisiológicos Respiratorios/efectos de los fármacos , Animales , Bleomicina/metabolismo , Regulación de la Expresión Génica , Glutatión Peroxidasa/metabolismo , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Oxidación-Reducción , Fibrosis Pulmonar/inducido químicamente , Superóxido Dismutasa/metabolismo , Glutatión Peroxidasa GPX1
18.
Anal Sci Adv ; 3(5-6): 198-204, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38716121

RESUMEN

Tolinapant (ASTX660), a pan-selective inhibitor of apoptosis protein antagonist with dual cIAP/XIAP activity, was identified as a clinical candidate in preclinical efficacy, pharmacokinetic and safety studies. In order to assess tolinapant in first-in-human Phase I/II clinical trials, a validated bioanalytical method was required to determine plasma pharmacokinetics. Tolinapant and d4-tolinapant were extracted from human plasma using liquid-liquid extraction. Separation chromatography was performed on a Acquity BEH C18 1.7 µM, 50 mm × 2.1 mm i.d. column, using a mobile phase of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. Mass spectrometry detection was performed by positive turbo ion spray ionisation, in multiple reaction monitoring mode. The method was validated according to the US Food and Drug Administration (FDA) guidelines. The method has a quantifiable linear range of 1-500 ng/mL (r 2 = 0.999). The intra- and inter-day coefficients of variation were < 11.4%. Dilution QC samples agreed with prepared concentrations, with a precision of 1.5% and accuracy of 101%. Tolinapant mean recoveries ranged from 85.1-94.4 % with negligible matrix effects. A highly sensitive and selective LC-MS/MS bioanalytical method was developed and validated. The method was successfully applied in Phase 1/2 clinical trials to determine the human pharmacokinetic profile of tolinapant.

19.
Rev Bras Med Trab ; 20(2): 311-316, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36127912

RESUMEN

Introduction: Green tobacco sickness affects tobacco growers while handling tobacco leaves, regardless of the cultivation stage. Objectives: To characterize the sociodemographic and occupational profiles of tobacco growers with green tobacco sickness, as well as their health habits. Methods: This was a cross-sectional, descriptive study with information from a database obtained from a previous study conducted in a Southern Brazilian municipality. The data were analyzed using absolute and relative frequency. Results: We identified 8 cases of tobacco growers with green tobacco sickness, whose sociodemographic and occupational profiles and health habits were described. Conclusions: The data obtained in this study corroborate the existing literature on tobacco growers. The sociodemographic and occupational profiles and the health habits of our study participants have already been described in other studies, as well as of tobacco growers without green tobacco sickness.

20.
Cells ; 11(23)2022 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-36497049

RESUMEN

Poly(ADP-ribose) polymerase 1 (PARP1), as a potential target for the experimental therapy of acute lung injury (ALI), was identified over 20 years ago. However, clinical translation of this concept was not possible due to the lack of clinically useful PARP inhibitors. With the clinical introduction of several novel, ultrapotent PARP inhibitors, the concept of PARP inhibitor repurposing has re-emerged. Here, we evaluated the effect of 5 clinical-stage PARP inhibitors in oxidatively stressed cultured human epithelial cells and monocytes in vitro and demonstrated that all inhibitors (1-30 µM) provide a comparable degree of cytoprotection. Subsequent in vivo studies using a murine model of ALI compared the efficacy of olaparib and rucaparib. Both inhibitors (1-10 mg/kg) provided beneficial effects against lung extravasation and pro-inflammatory mediator production-both in pre- and post-treatment paradigms. The underlying mechanisms include protection against cell dysfunction/necrosis, inhibition of NF-kB and caspase 3 activation, suppression of the NLRP3 inflammasome, and the modulation of pro-inflammatory mediators. Importantly, the efficacy of PARP inhibitors was demonstrated without any potentiation of DNA damage, at least as assessed by the TUNEL method. These results support the concept that clinically approved PARP inhibitors may be repurposable for the experimental therapy of ALI.


Asunto(s)
Lesión Pulmonar Aguda , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Ratones , Humanos , Animales , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Modelos Animales de Enfermedad , Lesión Pulmonar Aguda/tratamiento farmacológico , Pulmón , Mediadores de Inflamación/farmacología , Necrosis
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