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1.
Ecotoxicol Environ Saf ; 271: 115928, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38215666

RESUMEN

Nephrotoxicity is a common adverse effect induced by various chemicals, necessitating the development of reliable toxicity screening models for nephrotoxicity assessment. In this study, we assessed a group of nephrotoxicity indicators derived from different toxicity pathways, including conventional endpoints and kidney tubular injury biomarkers such as clusterin (CLU), kidney injury molecule-I (KIM-1), osteopontin (OPN), and neutrophil gelatinase-associated lipocalin (NGAL), using HK-2 and induced pluripotent stem cells (iPSCs)-derived renal proximal tubular epithelial-like cells (PTLs). Among the biomarkers tested, OPN emerged as the most discerning and precise marker. The predictive potential of OPN was tested using a panel of 10 nephrotoxic and 5 non-nephrotoxic compounds. The results demonstrated that combining OPN with the half-maximal inhibitory concentration (IC50) enhanced the diagnostic accuracy in both cellular models. Additionally, PTLs cells showed superior predictive efficacy for nephrotoxicity compared to HK-2 cells in this investigation. The two cellular models were utilized to evaluate the nephrotoxicity of lanthanum. The findings indicated that lanthanum possesses nephrotoxic properties; however, the degree of nephrotoxicity was relatively low, consistent with the outcomes of in vivo experiments.


Asunto(s)
Lantano , Osteopontina , Humanos , Osteopontina/metabolismo , Lantano/toxicidad , Lantano/metabolismo , Riñón , Túbulos Renales/metabolismo , Biomarcadores/metabolismo
2.
Sci Total Environ ; 953: 175980, 2024 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-39236823

RESUMEN

Assessing the bioaccessibility and bioavailability of cadmium (Cd) is crucial for effective evaluation of the exposure risk associated with intake of Cd-contaminated rice. However, limited studies have investigated the influence of gut microbiota on these two significant factors. In this study, we utilized in vitro gastrointestinal simulators, specifically the RIVM-M (with human gut microbial communities) and the RIVM model (without gut microbial communities), to determine the bioaccessibility of Cd in rice. Additionally, we employed the Caco-2 cell model to assess bioavailability. Our findings provide compelling evidence that gut microbiota significantly reduces Cd bioaccessibility and bioavailability (p<0.05). Notably, strong in vivo-in vitro correlations (IVIVC) were observed between the in vitro bioaccessibilities and bioavailabilities, as compared to the results obtained from an in vivo mouse bioassay (R2 = 0.63-0.65 and 0.45-0.70, respectively). Minerals such as copper (Cu) and iron (Fe) in the food matrix were found to be negatively correlated with Cd bioaccessibility in rice. Furthermore, the results obtained from the toxicokinetic (TK) model revealed that the predicted urinary Cd levels in the Chinese population, based on dietary Cd intake adjusted by in vitro bioaccessibility from the RIVM-M model, were consistent with the actual measured levels (p > 0.05). These results indicated that the RIVM-M model represents a potent approach for measuring Cd bioaccessibility and underscore the crucial role of gut microbiota in the digestion and absorption process of Cd. The implementation of these in vitro methods holds promise for reducing uncertainties in dietary exposure assessment.


Asunto(s)
Disponibilidad Biológica , Cadmio , Microbioma Gastrointestinal , Oryza , Oryza/metabolismo , Cadmio/metabolismo , Humanos , Animales , Ratones , Células CACO-2 , Contaminación de Alimentos/análisis , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/análisis
3.
Case Stud Transp Policy ; 12: 101014, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37162793

RESUMEN

The outbreak of COVID-19 has impacted the shipping industry while the extent of the impact is still not fully understood. To quantitatively investigate the relationship between pandemic-related factors and port operations, a panel regression analysis is conducted using data from three important Asian ports, Shenzhen, Hong Kong, and Singapore. Daily data from the Automatic Identification System (AIS), Oxford COVID-19 Government Response Tracker (OxCGRT) database, and port authorities from January 2020 to December 2021 are utilized. Local newly confirmed cases of ports tend to negatively impact cargo throughput, while worldwide newly confirmed cases outside of ports tend to positively impact cargo throughput. Overall, the policy implications are that ports with better control of COVID-19 reap the benefits of more cargo throughput. In addition, countermeasures against COVID-19 and other epidemics should be designed deliberately to minimize the side-effect on port operations and maritime transportation.

4.
Food Chem Toxicol ; 172: 113601, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36610472

RESUMEN

Cadmium accumulates in the kidney and causes inflammation. The NLRP3 inflammasome has been linked to the pathogenesis of inflammation. Hyperoside (HYP) possesses potent nephroprotective properties against of kidney injury. This study aimed to research the effects and related mechanism of HYP on Cd-induced kidney damage. Wide-type and NLRP3-/- mice were used to determine the role of NLRP3 inflammasome in Cd-induced renal dysfunction. Female C57BL/6 were treated with Cd (50 m,g/L) and HYP (25, 50 mg/kg) for 12 weeks. In vitro experiments, the human renal proximal-tubule epithelial cells (RPTEC/TERT1) were pretreated with HYP (50-200 µM) before exposure to Cd. NLRP3 deficiency attenuated Cd-induced NLRP3 activation, inflammation and kidney injury in mice. HYP treatment significantly alleviated Cd-induced kidney injury by decreasing indexes of kidney function, reducing pro-inflammatory cytokines release, decreasing ROS production and suppressing NLRP3 inflammasome activation. Moreover, treatment with siRNA targeting NLRP3 blocked the anti-inflammatory protective effect of HYP in Cd-treated cells. Additionally, HYP markedly inhibited Cd-induced MAPK/NF-κB pathway stimulation in vitro and in vivo. The findings indicated HYP conferred protection against Cd-induced kidney inflammation via suppression of NLRP3 inflammasome mediated by ROS/MAPK/NF-κB signaling. Our results thus support the notion of developing HYP as promising therapeutic candidate for Cd-induced kidney injury.


Asunto(s)
Inflamasomas , FN-kappa B , Humanos , Femenino , Ratones , Animales , FN-kappa B/metabolismo , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Cadmio/toxicidad , Cadmio/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal , Riñón , Inflamación/metabolismo
5.
Bioorg Med Chem Lett ; 22(2): 1247-50, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22172702
6.
Bioorg Med Chem Lett ; 21(23): 7205-9, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22001092

RESUMEN

In a discovery effort to find safe and effective DGAT-1 inhibitors, we have identified 2-phenyloxazole 4-carboxamide 1 as a conformationally constrained analog of a hydrazide hit, which was previously identified from high-throughput screening. Further optimization of this series has led to chemically more stable 2-phenyloxazole-based DGAT-1 inhibitor 25 with improved solubility, cell-based activity, and pharmacokinetic properties. Compound 25 also demonstrated in vivo efficacy in a diet-induced obesity (DIO) rat model.


Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores Enzimáticos , Oxazoles/química , Oxazoles/farmacología , Administración Oral , Animales , Peso Corporal , Diacilglicerol O-Acetiltransferasa/química , Modelos Animales de Enfermedad , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Humanos , Concentración 50 Inhibidora , Ratones , Estructura Molecular , Obesidad/tratamiento farmacológico , Oxazoles/uso terapéutico , Ratas , Solubilidad , Relación Estructura-Actividad
7.
Dis Markers ; 2021: 6482665, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34512815

RESUMEN

Diabetic retinopathy (DR) is a common chronic fundus disease, which has four different kinds of microvessel structure and microvascular lesions: microaneurysms (MAs), hemorrhages (HEs), hard exudates, and soft exudates. Accurate detection and counting of them are a basic but important work. The manual annotation of these lesions is a labor-intensive task in clinical analysis. To solve the problem, we proposed a novel segmentation method for different lesions in DR. Our method is based on a convolutional neural network and can be divided into encoder module, attention module, and decoder module, so we refer it as EAD-Net. After normalization and augmentation, the fundus images were sent to the EAD-Net for automated feature extraction and pixel-wise label prediction. Given the evaluation metrics based on the matching degree between detected candidates and ground truth lesions, our method achieved sensitivity of 92.77%, specificity of 99.98%, and accuracy of 99.97% on the e_ophtha_EX dataset and comparable AUPR (Area under Precision-Recall curve) scores on IDRiD dataset. Moreover, the results on the local dataset also show that our EAD-Net has better performance than original U-net in most metrics, especially in the sensitivity and F1-score, with nearly ten percent improvement. The proposed EAD-Net is a novel method based on clinical DR diagnosis. It has satisfactory results on the segmentation of four different kinds of lesions. These effective segmentations have important clinical significance in the monitoring and diagnosis of DR.


Asunto(s)
Algoritmos , Retinopatía Diabética/diagnóstico , Exudados y Transudados/diagnóstico por imagen , Fondo de Ojo , Interpretación de Imagen Asistida por Computador/métodos , Redes Neurales de la Computación , Retinopatía Diabética/diagnóstico por imagen , Humanos
8.
Mol Cancer Ther ; 5(11): 2644-58, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17121911

RESUMEN

The cyclin-dependent protein kinases are key regulators of cell cycle progression. Aberrant expression or altered activity of distinct cyclin-dependent kinase (CDK) complexes results in escape of cells from cell cycle control, leading to unrestricted cell proliferation. CDK inhibitors have the potential to induce cell cycle arrest and apoptosis in cancer cells, and identifying small-molecule CDK inhibitors has been a major focus in cancer research. Several CDK inhibitors are entering the clinic, the most recent being selective CDK2 and CDK4 inhibitors. We have identified a diaminopyrimidine compound, R547, which is a potent and selective ATP-competitive CDK inhibitor. In cell-free assays, R547 effectively inhibited CDK1/cyclin B, CDK2/cyclin E, and CDK4/cyclin D1 (K(i) = 1-3 nmol/L) and was inactive (K(i) > 5,000 nmol/L) against a panel of >120 unrelated kinases. In vitro, R547 effectively inhibited the proliferation of tumor cell lines independent of multidrug resistant status, histologic type, retinoblastoma protein, or p53 status, with IC(50)s

Asunto(s)
Antineoplásicos/farmacología , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Pirimidinas/farmacología , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Apoptosis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos Clínicos Fase I como Asunto , Quinasas Ciclina-Dependientes/metabolismo , Femenino , Fase G1/efectos de los fármacos , Fase G2/efectos de los fármacos , Genes MDR/efectos de los fármacos , Humanos , Ratones , Ratones Desnudos , Fosforilación/efectos de los fármacos , Pirimidinas/farmacocinética , Pirimidinas/uso terapéutico , Ratas , Ratas Endogámicas F344 , Retinoblastoma/tratamiento farmacológico , Retinoblastoma/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
9.
J Med Chem ; 49(22): 6549-60, 2006 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-17064073

RESUMEN

The cyclin-dependent kinases (CDKs) and their cyclin partners are key regulators of the cell cycle. Since deregulation of CDKs is found with high frequency in many human cancer cells, pharmacological inhibition of CDKs with small molecules has the potential to provide an effective strategy for the treatment of cancer. The 2,4-diamino-5-ketopyrimidines 6 reported here represent a novel class of potent and ATP-competitive inhibitors that selectively target the cyclin-dependent kinase family. This diaminopyrimidine core with a substituted 4-piperidine moiety on the C2-amino position and 2-methoxybenzoyl at the C5 position has been identified as the critical structure responsible for the CDK inhibitory activity. Further optimization has led to a good number of analogues that show potent inhibitory activities against CDK1, CDK2, and CDK4 but are inactive against a large panel of serine/threonine and tyrosine kinases (K(i) > 10 microM). As one of these representative analogues, compound 39 (R547) has the best CDK inhibitory activities (K(i) = 0.001, 0.003, and 0.001 microM for CDK1, CDK2, and CDK4, respectively) and excellent in vitro cellular potency, inhibiting the growth of various human tumor cell lines including an HCT116 cell line (IC(50) = 0.08 microM). An X-ray crystal structure of 39 bound to CDK2 has been determined in this study, revealing a binding mode that is consistent with our SAR. Compound 39 demonstrates significant in vivo efficacy in the HCT116 human colorectal tumor xenograft model in nude mice with up to 95% tumor growth inhibition. On the basis of its superior overall profile, 39 was chosen for further evaluation and has progressed into Phase I clinical trial for the treatment of cancer.


Asunto(s)
Antineoplásicos/farmacología , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/farmacocinética , Pirimidinas/farmacología , Pirimidinas/farmacocinética , Animales , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Fenómenos Químicos , Química Física , Quinasa 2 Dependiente de la Ciclina/química , Diseño de Fármacos , Femenino , Humanos , Indicadores y Reactivos , Cinética , Ratones , Ratones Desnudos , Modelos Moleculares , Relación Estructura-Actividad , Difracción de Rayos X
10.
ACS Med Chem Lett ; 4(2): 197-200, 2013 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24900642

RESUMEN

Organic impurities in compound libraries are known to often cause false-positive signals in screening campaigns for new leads, but organic impurities do not fully account for all false-positive results. We discovered inorganic impurities in our screening library that can also cause positive signals for a variety of targets and/or readout systems, including biochemical and biosensor assays. We investigated in depth the example of zinc for a specific project and in retrospect in various HTS screens at Roche and propose a straightforward counter screen using the chelator TPEN to rule out inhibition caused by zinc.

11.
J Med Chem ; 54(7): 2433-46, 2011 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-21413799

RESUMEN

Diacylglycerol acyltransferase-1 (DGAT-1) is the enzyme that catalyzes the final and committed step of triglyceride formation, namely, the acylation of diacylglycerol with acyl coenzyme A. DGAT-1 deficient mice demonstrate resistance to weight gain on high fat diet, improved insulin sensitivity, and reduced liver triglyceride content. Inhibition of DGAT-1 thus represents a potential novel approach for the treatment of obesity, dyslipidemia, and metabolic syndrome. In this communication, we report the identification of the lead structure 6 and our lead optimization efforts culminating in the discovery of potent, selective, and orally efficacious carboxylic acid derivatives of 2-phenyl-5-trifluoromethyloxazole-4-carboxamides. In particular, compound 29 (DGAT-1 enzyme assay, IC(50) = 57 nM; CHO-K1 cell triglyceride formation assay, EC(50) = 0.5 µM) demonstrated dose dependent inhibition of weight gain in diet induced obese (DIO) rats (0.3, 1, and 3 mg/kg, p.o., qd) during a 21-day efficacy study. Furthermore, compound 29 demonstrated improved glucose tolerance determined by an oral glucose tolerance test (OGTT).


Asunto(s)
Amidas/química , Amidas/farmacología , Ácidos Carboxílicos/química , Diabetes Mellitus/tratamiento farmacológico , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Descubrimiento de Drogas , Obesidad/tratamiento farmacológico , Oxazoles/química , Oxazoles/farmacología , Administración Oral , Amidas/administración & dosificación , Amidas/farmacocinética , Animales , Línea Celular , Diabetes Mellitus/enzimología , Perros , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Humanos , Concentración 50 Inhibidora , Masculino , Ratones , Obesidad/enzimología , Oxazoles/administración & dosificación , Oxazoles/farmacocinética , Ratas
12.
Bioorg Med Chem Lett ; 17(8): 2134-8, 2007 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-17303421

RESUMEN

A novel series of quinolinyl-methylene-thiazolinones has been identified as potent and selective cyclin-dependent kinase 1 (CDK1) inhibitors. Their synthesis and structure activity relationships (SAR) are described. Representative compounds from this class reversibly inhibit CDK1 activity in vitro, and block cell cycle progression in human tumor cell lines, suggesting a potential use as antitumor agents.


Asunto(s)
Proteína Quinasa CDC2/antagonistas & inhibidores , Tiazoles/síntesis química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Relación Estructura-Actividad , Tiazoles/farmacología
14.
Bioorg Med Chem ; 13(16): 4835-41, 2005 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-15953730
15.
Bioorg Med Chem Lett ; 13(15): 2465-8, 2003 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-12852944

RESUMEN

A novel class of 3,5,6-trisubstituted naphthostyril analogues was designed and synthesized to study the structure-activity relationship for inhibition of cyclin-dependent kinase 2 (CDK2). These compounds, particularly molecules with side-chain modifications providing additional hydrogen bonding capability, were demonstrated to be potent CDK2 inhibitors with cellular activities consistent with CDK2 inhibition. These molecules inhibited tumor cell proliferation and G1-S and G2-M cell-cycle progression in vitro. The X-ray crystal structure of a 2-aminoethyleneamine derivative bound to CDK2, refined to 2.5A resolution, is presented.


Asunto(s)
Quinasas CDC2-CDC28/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Naftalenos/síntesis química , Naftalenos/farmacología , Pirroles/síntesis química , Pirroles/farmacología , Antimetabolitos , Bromodesoxiuridina , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Cristalografía por Rayos X , Quinasa 2 Dependiente de la Ciclina , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Indicadores y Reactivos , Modelos Moleculares , Conformación Molecular , Oxidación-Reducción , Sales de Tetrazolio , Tiazoles
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