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1.
J Pharm Sci ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38608727

RESUMEN

The preparation of amorphous solid dispersions (ASDs) represents a promising strategy for addressing the solubility limitations of poorly soluble drugs, facilitating enhanced oral absorption. Acidic polymers such as cellulose acetate phthalate (CAP) and hydroxypropyl methylcellulose phthalate (HPMCP) have emerged as effective carriers for ASDs. Although the hydrolytic degradation of these polymers has been documented, its impact on the stability of ASDs has not been systematically investigated. This research aimed to explore the potential hydrolysis of CAP and HPMCP and how it influences the stability of ASDs containing ketoconazole (KTZ), at drug loadings of 10 % and 50 %. Our study utilized thermal analysis, infrared spectroscopy, and evaluations of physical and chemical stability. The results revealed that although KTZ remained physically stable in all ASDs over 60 days under various stability conditions, the emergence of crystalline phthalic acid (PA), a byproduct of polymer hydrolysis, was observed at elevated temperatures and relative humidity levels. The acidic microenvironment fostered by the release of PA further catalyzed drug chemical degradation. This study underscores the susceptibility of CAP and HPMCP to hydrolytic degradation, highlighting the inherent risk of PA-induced drug degradation, particularly for acid-labile compounds. These insights into the understanding of polymer hydrolysis in ASDs pave the way for the development of targeted approaches to safeguard drug stability and optimize pharmaceutical formulations for enhanced bioavailability, efficacy, and safety.

2.
bioRxiv ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38659794

RESUMEN

Pulmonary Mycobacterium tuberculosis (Mtb) infection results in highly heterogeneous lesions ranging from granulomas with central necrosis to those primarily comprised of alveolitis. While alveolitis has been associated with prior immunity in human post-mortem studies, the drivers of these distinct pathologic outcomes are poorly understood. Here, we show that these divergent lesion structures can be modeled in C3HeB/FeJ mice and are regulated by prior immunity. Using quantitative imaging, scRNAseq, and flow cytometry, we demonstrate that Mtb infection in the absence of prior immunity elicits dysregulated neutrophil recruitment and necrotic granulomas. In contrast, prior immunity induces rapid recruitment and activation of T cells, local macrophage activation, and diminished late neutrophil responses. Depletion studies at distinct infection stages demonstrated that neutrophils are required for early necrosis initiation and necrosis propagation at chronic stages, whereas early CD4 T cell responses prevent neutrophil feedforward circuits and necrosis. Together, these studies reveal fundamental determinants of tuberculosis lesion structure and pathogenesis, which have important implications for new strategies to prevent or treat tuberculosis.

3.
J Med Chem ; 66(18): 13135-13147, 2023 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-37724542

RESUMEN

A series of dihydropyridinone (DHP) compounds was prepared and evaluated for MGAT2 activity. The efforts led to the identification of novel tetrazolones with potent MGAT2 inhibitory activity and favorable in vitro profiles. Further tests of select analogues in mouse models revealed significant reduction in food intake and body weight. Subsequent studies in MGAT2 knockout mice with the lead candidate 12 (BMS-986172) showed on-target- and mechanism-based pharmacology. Moreover, its favorable pharmacokinetic (PK) profile and the lack of species variability in the glucuronidation potential resulted in a greater confidence level in the projection of a low dose for achieving targeted efficacious exposures in humans. Consistent with these projections, PK data from a phase 1 trial confirmed that targeted efficacious exposures could be achieved at a low dose in humans, which supported compound 12 as our second and potentially superior development candidate for the treatment of various metabolic disorders.


Asunto(s)
Enfermedades Metabólicas , Piridonas , Animales , Humanos , Ratones , Peso Corporal , Enfermedades Metabólicas/tratamiento farmacológico , Piridonas/química , Piridonas/farmacología , N-Acetilglucosaminiltransferasas/antagonistas & inhibidores
4.
Bioorg Med Chem Lett ; 91: 129362, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37295614

RESUMEN

Inhibition of monoacylglycerol transferase 2 (MGAT2) has recently emerged as a potential therapeutic strategy for the treatment of metabolic diseases such as obesity, diabetes and non-alcoholic steatohepatitis (NASH). Metabolism studies with our clinical lead (1) suggested variability in in vitro glucuronidation rates in liver microsomes across species, which made projection of human doses challenging. In addition, the observation of deconjugation of the C3-C4 double bond in the dihydropyridinone ring of 1 in solution had the potential to complicate its clinical development. This report describes our lead optimization efforts in a novel pyridinone series, exemplified by compound 33, which successfully addressed both of these potential issues.


Asunto(s)
Enfermedades Metabólicas , Monoglicéridos , Humanos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Inhibidores Enzimáticos/química , Obesidad/tratamiento farmacológico , Enfermedades Metabólicas/tratamiento farmacológico
5.
Bioorg Med Chem ; 85: 117273, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37030194

RESUMEN

GPR40 AgoPAMs are highly effective antidiabetic agents that have a dual mechanism of action, stimulating both glucose-dependent insulin and GLP-1 secretion. The early lipophilic, aromatic pyrrolidine and dihydropyrazole GPR40 AgoPAMs from our laboratory were highly efficacious in lowering plasma glucose levels in rodents but possessed off-target activities and triggered rebound hyperglycemia in rats at high doses. A focus on increasing molecular complexity through saturation and chirality in combination with reducing polarity for the pyrrolidine AgoPAM chemotype resulted in the discovery of compound 46, which shows significantly reduced off-target activities as well as improved aqueous solubility, rapid absorption, and linear PK. In vivo, compound 46 significantly lowers plasma glucose levels in rats during an oral glucose challenge yet does not demonstrate the reactive hyperglycemia effect at high doses that was observed with earlier GPR40 AgoPAMs.


Asunto(s)
Glucemia , Hiperglucemia , Ratas , Animales , Receptores Acoplados a Proteínas G , Péptido 1 Similar al Glucagón , Hipoglucemiantes/farmacología , Pirrolidinas/farmacología , Pirrolidinas/química , Insulina
6.
J Immunother Cancer ; 11(12)2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-38164756

RESUMEN

BACKGROUND: Myelodysplastic syndromes (MDS) arise from somatic mutations acquired in hematopoietic stem and progenitor cells, causing cytopenias and predisposing to transformation into secondary acute myeloid leukemia (sAML). Recurrent mutations in spliceosome genes, including U2AF1, are attractive therapeutic targets as they are prevalent in MDS and sAML, arise early in neoplastic cells, and are generally absent from normal cells, including normal hematopoietic cells. MDS and sAML are susceptible to T cell-mediated killing, and thus engineered T-cell immunotherapies hold promise for their treatment. We hypothesized that targeting spliceosome mutation-derived neoantigens with transgenic T-cell receptor (TCR) T cells would selectively eradicate malignant cells in MDS and sAML. METHODS: We identified candidate neoantigen epitopes from recurrent protein-coding mutations in the spliceosome genes SRSF2 and U2AF1 using a multistep in silico process. Candidate epitopes predicted to bind human leukocyte antigen (HLA) class I, be processed and presented from the parent protein, and not to be subject to tolerance then underwent in vitro immunogenicity screening. CD8+ T cells recognizing immunogenic neoantigen epitopes were evaluated in in vitro assays to assess functional avidity, confirm the predicted HLA restriction, the potential for recognition of similar peptides, and the ability to kill neoplastic cells in an antigen-specific manner. Neoantigen-specific TCR were sequenced, cloned into lentiviral vectors, and transduced into third-party T cells after knock-out of endogenous TCR, then tested in vitro for specificity and ability to kill neoplastic myeloid cells presenting the neoantigen. The efficacy of neoantigen-specific T cells was evaluated in vivo in a murine cell line-derived xenograft model. RESULTS: We identified two neoantigens created from a recurrent mutation in U2AF1, isolated CD8+ T cells specific for the neoantigens, and demonstrated that transferring their TCR to third-party CD8+ T cells is feasible and confers specificity for the U2AF1 neoantigens. Finally, we showed that these neoantigen-specific TCR-T cells do not recognize normal hematopoietic cells but efficiently kill malignant myeloid cells bearing the specific U2AF1 mutation, including primary cells, in vitro and in vivo. CONCLUSIONS: These data serve as proof-of-concept for developing precision medicine approaches that use neoantigen-directed T-cell receptor-transduced T cells to treat MDS and sAML.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Humanos , Ratones , Animales , Linfocitos T CD8-positivos , Factor de Empalme U2AF/genética , Factor de Empalme U2AF/metabolismo , Antígenos de Neoplasias , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/terapia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/metabolismo , Epítopos/metabolismo
7.
Colloids Surf B Biointerfaces ; 216: 112512, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35533561

RESUMEN

In this study, we have directly incorporated nanographene oxide (nGO) into a hydrophobic drug for enhanced dissolution performance through an antisolvent technique. Apixaban (APX) drug composites were synthesized with nGO incorporation ranging from 0.8% to 2.0% concentration. It was observed that the nGO was successfully embedded without any changes to the original drug crystal structure or physical properties. Dissolution of the drug composites was evaluated using US Pharmacopeia Paddle Method (USP 42). The time needed to reach a 50% release (T50) reduced from 106 min to 24 min with the integration of 1.96% nGO in APX and the T80 also dropped accordingly. Alternatively, dissolution rate showed promising performance with increase in nGO concentration. Initial dissolution rate increased dramatically from 74 µg/min to 540 µg/min. Further, work done in intestinal media revealed T50 went from not dissolving to 79.0 min. Decreased lipophilicity or logP value and increased aqueous solubility are both accredited to hydrophilic nGO water dispersion, producing a hydrophilic channel into the drug crystal surfaces through intermolecular interaction. Additionally, physical, and chemical characterizations confirm that hydrophobic apixaban was successfully transformed into a hydrophilic composite, showing potential for this technology to improve dissolution rate of a model hydrophobic compound.


Asunto(s)
Grafito , Pirazoles , Piridonas , Grafito/química , Interacciones Hidrofóbicas e Hidrofílicas , Nanopartículas , Óxidos , Pirazoles/química , Piridonas/química , Solubilidad , Agua/química
8.
J Med Chem ; 64(19): 14773-14792, 2021 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-34613725

RESUMEN

MGAT2 inhibition is a potential therapeutic approach for the treatment of metabolic disorders. High-throughput screening of the BMS internal compound collection identified the aryl dihydropyridinone compound 1 (hMGAT2 IC50 = 175 nM) as a hit. Compound 1 had moderate potency against human MGAT2, was inactive vs mouse MGAT2 and had poor microsomal metabolic stability. A novel chemistry route was developed to synthesize aryl dihydropyridinone analogs to explore structure-activity relationship around this hit, leading to the discovery of potent and selective MGAT2 inhibitors 21f, 21s, and 28e that are stable to liver microsomal metabolism. After triaging out 21f due to its inferior in vivo potency, pharmacokinetics, and structure-based liabilities and tetrazole 28e due to its inferior channel liability profile, 21s (BMS-963272) was selected as the clinical candidate following demonstration of on-target weight loss efficacy in the diet-induced obese mouse model and an acceptable safety and tolerability profile in multiple preclinical species.


Asunto(s)
Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Ensayos Analíticos de Alto Rendimiento/métodos , Enfermedades Metabólicas/tratamiento farmacológico , N-Acetilglucosaminiltransferasas/antagonistas & inhibidores , Animales , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/uso terapéutico , Humanos , Relación Estructura-Actividad
9.
ACS Med Chem Lett ; 12(7): 1143-1150, 2021 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-34267885

RESUMEN

IDO1 inhibitors have shown promise as immunotherapies for the treatment of a variety of cancers, including metastatic melanoma and renal cell carcinoma. We recently reported the identification of several novel heme-displacing IDO1 inhibitors, including the clinical molecules linrodostat (BMS-986205) and BMS-986242. Both molecules contain quinolines that, while being present in successful medicines, are known to be potentially susceptible to oxidative metabolism. Efforts to swap this quinoline with an alternative aromatic system led to the discovery of 2,3-disubstituted pyridines as suitable replacements. Further optimization, which included lowering ClogP in combination with strategic fluorine incorporation, led to the discovery of compound 29, a potent, selective IDO1 inhibitor with robust pharmacodynamic activity in a mouse xenograft model.

10.
Molecules ; 26(7)2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33807401

RESUMEN

The aim of this work is to present an approach to enhance the dissolution of progestin medication, megestrol acetate (also known as MEGACE), for improving the dissolution rate and kinetic solubility by incorporating nano graphene oxide (nGO). An antisolvent precipitation process was investigated for nGO-drug composite preparation, where prepared composites showed crystalline properties that were similar to the pure drug but enhanced aqueous dispersibility and colloidal stability. To validate the efficient release profile of composite, in vitro dissolution testing was carried out using United States Pharmacopeia, USP-42 paddle method, with gastric pH (1.4) and intestinal pH (6.5) solutions to mimic in vivo conditions. Pure MA is practically insoluble (2 µg/mL at 37 °C). With the incorporation of nGO, it was possible to dissolve nearly 100% in the assay. With the incorporation of 1.0% of nGO, the time required to dissolve 50% and 80% of drug, namely T50 and T80, decreased from 138.0 min to 27.0 min, and the drug did not dissolve for 97.0 min in gastric media, respectively. Additionally, studies done in intestinal media have revealed T50 did not dissolve for 92.0 min. This work shows promise in incorporating functionalized nanoparticles into the crystal lattice of poorly soluble drugs to improve dissolution rate.


Asunto(s)
Excipientes/química , Grafito/química , Acetato de Megestrol , Nanopartículas/química , Disponibilidad Biológica , Química Farmacéutica , Composición de Medicamentos , Interacciones Hidrofóbicas e Hidrofílicas , Acetato de Megestrol/química , Acetato de Megestrol/farmacocinética , Solubilidad
11.
Pharm Res ; 38(5): 901-914, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33880721

RESUMEN

PURPOSE: The use of two solvent-casted film methods to select optimal polymer compositions for amorphous solid dispersions prepared to support preclinical pharmacokinetic and toxicology studies is described. METHODS: Evaporation of solvent from cover slips by using nitrogen flow, and solvent removal from vials by using rotary evaporation were employed. The films prepared on cover slips were evaluated under the microscope to determine crystallinity. The methods were validated by scaling up corresponding SDDs, evaluating SDD's dissolution, and comparing those results to the dissolution of drug-polymer films. Subsequently, SDD suspensions were prepared and dosed orally to rats to determine pharmacokinetic parameters. This was done by using three compounds from our pipeline and evaluating multiple polymers. RESULTS: The dissolution of generated films showed good agreement with the dissolution of spray dried dispersions when the films were fully amorphous (Compound A and B). In contrast, there was disagreement between film and SDD dissolution when the films had crystallized (Compound C). The in vivo exposure results indicated that the polymer choice based on the film screening methods would have been accurate for drug-polymer films that were amorphous (Compound A and B). Two additional case studies (Compound D and E) are presented, showing good agreement between in vivo and in vitro results. CONCLUSION: This study established the ability of two film casting screening methods to predict the in vitro and in vivo performance of corresponding SDDs, provided that the films are fully amorphous.


Asunto(s)
Composición de Medicamentos/métodos , Polímeros/química , Animales , Evaluación Preclínica de Medicamentos/métodos , Liberación de Fármacos , Ratas , Solubilidad , Solventes/química , Pruebas de Toxicidad/métodos , Difracción de Rayos X
12.
ACS Med Chem Lett ; 12(2): 288-294, 2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33603977

RESUMEN

Indoleamine 2,3-dioxygenase 1 (IDO1) is a heme-containing dioxygenase enzyme implicated in cancer immune response. This account details the discovery of BMS-986242, a novel IDO1 inhibitor designed for the treatment of a variety of cancers including metastatic melanoma and renal cell carcinoma. Given the substantial interest around this target for cancer immunotherapy, we sought to identify a structurally differentiated clinical candidate that performs comparably to linrodostat (BMS-986205) in terms of both in vitro potency and in vivo pharmacodynamic effect in a mouse xenograft model. On the basis of its preclinical profile, BMS-986242 was selected as a candidate for clinical development.

13.
J Appl Gerontol ; 40(11): 1511-1516, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33487058

RESUMEN

The purpose of this study was to identify the perceptions and attitudes of African American congregants toward dementia before and after attending a dementia-focused workshop. Six churches in Metropolitan Atlanta, Georgia, hosted the workshops. Attendees (N = 171) participated in a free association exercise to evaluate their perceptions and attitudes toward dementia. Before and after the workshop, participants wrote words and phrases that occurred to them when they thought of dementia. Content analysis was used to identify themes. Before the workshop, participants' responses tended to include negative language (e.g., fear, memory loss, sadness). After the workshop, participants expressed more positive words (e.g., support, hopefulness, caring). These findings suggest that education can change congregants' perceptions about dementia and potentially reduce dementia-associated stigma. This change will allow families to feel comfortable both interacting with and seeking help from those in their faith communities.


Asunto(s)
Negro o Afroamericano , Demencia , Actitud , Conocimientos, Actitudes y Práctica en Salud , Humanos , Percepción , Religión , Estigma Social
14.
Biomed Microdevices ; 22(3): 52, 2020 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-32770358

RESUMEN

Although microfluidic micro-electromechanical systems (MEMS) are well suited to investigate the effects of mechanical force on large populations of cells, their high-throughput capabilities cannot be fully leveraged without optimizing the experimental conditions of the fluid and particles flowing through them. Parameters such as flow velocity and particle size are known to affect the trajectories of particles in microfluidic systems and have been studied extensively, but the effects of temperature and buffer viscosity are not as well understood. In this paper, we explored the effects of these parameters on the timing of our own cell-impact device, the µHammer, by first tracking the velocity of polystyrene beads through the device and then visualizing the impact of these beads. Through these assays, we find that the timing of our device is sensitive to changes in the ratio of inertial forces to viscous forces that particles experience while traveling through the device. This sensitivity provides a set of parameters that can serve as a robust framework for optimizing device performance under various experimental conditions, without requiring extensive geometric redesigns. Using these tools, we were able to achieve an effective throughput over 360 beads/s with our device, demonstrating the potential of this framework to improve the consistency of microfluidic systems that rely on precise particle trajectories and timing.


Asunto(s)
Dispositivos Laboratorio en un Chip , Sistemas Microelectromecánicos/instrumentación , Tampones (Química) , Diseño de Equipo , Microesferas , Tamaño de la Partícula , Poliestirenos/química , Temperatura , Viscosidad
15.
J Clin Invest ; 130(10): 5127-5141, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32831296

RESUMEN

Proteins created from recurrent fusion genes like CBFB-MYH11 are prevalent in acute myeloid leukemia (AML), often necessary for leukemogenesis, persistent throughout the disease course, and highly leukemia specific, making them attractive neoantigen targets for immunotherapy. A nonameric peptide derived from a prevalent CBFB-MYH11 fusion protein was found to be immunogenic in HLA-B*40:01+ donors. High-avidity CD8+ T cell clones isolated from healthy donors killed CBFB-MYH11+ HLA-B*40:01+ AML cell lines and primary human AML samples in vitro. CBFB-MYH11-specific T cells also controlled CBFB-MYH11+ HLA-B*40:01+ AML in vivo in a patient-derived murine xenograft model. High-avidity CBFB-MYH11 epitope-specific T cell receptors (TCRs) transduced into CD8+ T cells conferred antileukemic activity in vitro. Our data indicate that the CBFB-MYH11 fusion neoantigen is naturally presented on AML blasts and enables T cell recognition and killing of AML. We provide proof of principle for immunologically targeting AML-initiating fusions and demonstrate that targeting neoantigens has clinical relevance even in low-mutational frequency cancers like fusion-driven AML. This work also represents a first critical step toward the development of TCR T cell immunotherapy targeting fusion gene-driven AML.


Asunto(s)
Leucemia Mieloide Aguda , Animales , Carcinogénesis , Subunidad beta del Factor de Unión al Sitio Principal/genética , Humanos , Leucocitos , Ratones , Mutación , Cadenas Pesadas de Miosina/genética , Proteínas de Fusión Oncogénica/genética
16.
J Fish Biol ; 96(1): 194-201, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31729024

RESUMEN

We explored the macroevolutionary dynamics of miniaturisation in New World anchovies by integrating a time-calibrated phylogeny, geometric morphometrics and phylogenetic comparative methods. We found that the paedomorphic species Amazonsprattus scintilla occupies a novel region of shape space, while the dwarf species Anchoviella manamensis has an overall shape consistent with other anchovies. We found that miniaturisation did not increase overall clade disparity in size or shape beyond the expectations of Brownian motion, nor were there differences in rates of size or shape evolution among clades. Overall, our study shows that while the mode of miniaturisation influences shape evolution, the phenotypic novelty produced by the evolution of miniaturisation did not seem to alter macroevolutionary dynamics.


Asunto(s)
Peces/anatomía & histología , Miniaturización , Animales , Evolución Biológica , Tamaño Corporal/genética , Peces/clasificación , Peces/genética , Filogenia
17.
J R Soc Interface ; 16(156): 20190239, 2019 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-31362613

RESUMEN

Dry adhesives using surface microstructures inspired by climbing animals have been recognized for their potentially novel capabilities, with relevance to a range of applications including pick-and-place handling. Past work has suggested that performance may be strongly dependent on variability in the critical defect size among fibrillar sub-contacts. However, it has not been directly verified that the resulting adhesive strength distribution is well described by the statistical theory of fracture used. Using in situ contact visualization, we characterize adhesive strength on a fibril-by-fibril basis for a synthetic fibrillar adhesive. Two distinct detachment mechanisms are observed. The fundamental, design-dependent mechanism involves defect propagation from within the contact. The secondary mechanism involves defect propagation from fabrication imperfections at the perimeter. The existence of two defect populations complicates characterization of the statistical properties. This is addressed by using the mean order ranking method to isolate the fundamental mechanism. The statistical properties obtained are subsequently used within a bimodal framework, allowing description of the secondary mechanism. Implications for performance are discussed, including the improvement of strength associated with elimination of fabrication imperfections. This statistical analysis of defect-dependent detachment represents a more complete approach to the characterization of fibrillar adhesives, offering new insight for design and fabrication.


Asunto(s)
Adhesivos/química , Materiales Biomiméticos/química , Modelos Químicos , Animales , Lagartos
18.
Pharmacol Res Perspect ; 7(3): e00488, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31149343

RESUMEN

In this study, we describe a novel approach for collecting bile from dogs and cynomolgus monkeys for metabolite profiling, ultrasound-guided cholecystocentesis (UCC). Sampling bile by UCC twice within 24 hours was well tolerated by dogs and monkeys. In studies with atorvastatin (ATV) the metabolite profiles were similar in bile obtained through UCC and from bile duct-cannulated (BDC) dogs. Similar results were observed in UCC and BDC monkeys as well. In both monkey and dog, the primary metabolic pathway observed for ATV was oxidative metabolism. The 2-hydroxy- and 4-hydroxyatorvastatin metabolites were the major oxidation products, which is consistent with previously published metabolite profiles. S-cysteine and glucuronide conjugates were also observed. UCC offers a viable alternative to bile duct cannulation for collection of bile for metabolite profiling of compounds that undergo biliary excretion, given the similar metabolite profiles in bile obtained via each method. Use of UCC for metabolite profiling may reduce the need for studies using BDC animals, a resource-intensive model.


Asunto(s)
Atorvastatina/administración & dosificación , Bilis/química , Metabolómica/métodos , Animales , Atorvastatina/farmacocinética , Conductos Biliares/cirugía , Cromatografía Líquida de Alta Presión , Perros , Glucurónidos/análisis , Macaca fascicularis , Estrés Oxidativo , Ultrasonografía Intervencional
19.
Interv Neuroradiol ; 25(3): 322-329, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31138039

RESUMEN

We present a case of a novel restrictive cerebral venopathy in a child, consisting of a bilateral network of small to medium cortical veins without evidence of arteriovenous shunting, absence of the deep venous system, venous ischemia, elevated intracranial pressure, and intracranial calcifications. The condition is unlike other diseases characterized by networks of small veins, including cerebral proliferative angiopathy, Sturge-Weber syndrome, or developmental venous anomaly. While this case may be the result of an anatomic variation leading to the congenital absence of or early occlusion of the deep venous system, the insidious nature over many years argues against this. The absence of large cortical veins suggests a congenital abnormality of the venous structure. The child's presentation with a seizure-like event followed by protracted hemiparesis is consistent with venous ischemia. We propose that this is likely to represent a new clinicopathological entity.


Asunto(s)
Corteza Cerebral/diagnóstico por imagen , Venas Cerebrales/diagnóstico por imagen , Trastornos Cerebrovasculares/diagnóstico por imagen , Adolescente , Isquemia Encefálica/etiología , Corteza Cerebral/irrigación sanguínea , Parálisis Cerebral/complicaciones , Trastornos Cerebrovasculares/complicaciones , Humanos , Imagen por Resonancia Magnética , Masculino , Examen Neurológico , Paresia/etiología , Convulsiones/etiología , Tomografía Computarizada por Rayos X , Derivación Ventriculoperitoneal
20.
J Pediatr Hematol Oncol ; 41(1): e34-e37, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29432310

RESUMEN

Congenital brain tumors are rare, representing <2% of all childhood brain tumors. Of these, ependymoblastoma is a profoundly aggressive embryonal brain tumor that is included in the diagnostic entity known as an embryonal tumor with multilayered rosettes. This report of a congenital ependymoblastoma diagnosed at birth aims to highlight how much remains unknown about embryonal tumor with multilayered rosettes and the devastating prognosis of this condition. Despite recent advancements made in identifying molecular targets for therapy, this tumor continues to have a high rate of recurrence with few successful treatment options, especially when diagnosed in the newborn period.


Asunto(s)
Neoplasias Encefálicas/congénito , Neoplasias Encefálicas/diagnóstico por imagen , Tumores Neuroectodérmicos Primitivos/congénito , Tumores Neuroectodérmicos Primitivos/diagnóstico por imagen , Adulto , Neoplasias Encefálicas/patología , Femenino , Humanos , Recién Nacido , Tumores Neuroectodérmicos Primitivos/patología , Embarazo
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