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1.
Orbit ; 42(3): 332-335, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34847834

RESUMEN

Patients with COVID-19 have been reported to have elevated coagulation factors, which is a well-documented cause of venous thromboembolism events such as deep vein thrombosis and pulmonary embolism. Other venous thrombotic events, however, such as cavernous sinus thrombosis (CST) have been less commonly observed, specifically in combination with primary orbital cellulitis. Due to its unique anatomic location, the cavernous sinus is susceptible to thrombophlebitis processes including septic thrombosis and thrombosis most commonly from sinusitis. Many studies have shown that in the antibiotic era thromboembolic events of the cavernous sinus are less common due to infection spread from the orbit or facial region. This case report describes a 17-year-old COVID-19 positive male who presented with a left-sided primary orbital cellulitis with CST without radiographic evidence of ipsilateral sinus disease.


Asunto(s)
COVID-19 , Trombosis del Seno Cavernoso , Seno Cavernoso , Celulitis Orbitaria , Trombosis , Humanos , Masculino , Adolescente , Celulitis Orbitaria/diagnóstico por imagen , Celulitis Orbitaria/tratamiento farmacológico , Trombosis del Seno Cavernoso/diagnóstico por imagen , Trombosis del Seno Cavernoso/etiología , Seno Cavernoso/diagnóstico por imagen , Trombosis/complicaciones , Celulitis (Flemón)/complicaciones
2.
Bioorg Med Chem ; 25(20): 5433-5440, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28807574

RESUMEN

We describe our efforts to improve the pharmacokinetic properties of a mechanism-based suicide inhibitor of the polyamine biosynthetic enzyme S-adenosylmethionine decarboxylase (AdoMetDC), essential for the survival of the eukaryotic parasite Trypanosoma brucei responsible for Human African Trypanosomiasis (HAT). The lead compound, 5'-(((Z)-4-amino-2-butenyl)methylamino)-5'-deoxyadenosine (1, also known as MDL 73811, or AbeAdo), has curative efficacy at a low dosage in a hemolymphatic model of HAT but displayed no demonstrable effect in a mouse model of the CNS stage of HAT due to poor blood-brain barrier permeation. Therefore, we prepared and evaluated an extensive set of analogs with modifications in the aminobutenyl side chain, the 5'-amine, the ribose, and the purine fragments. Although we gained valuable structure-activity insights from this comprehensive dataset, we did not gain traction on improving the prospects for CNS penetration while retaining the potent antiparasitic activity and metabolic stability of the lead compound 1.


Asunto(s)
Adenosilmetionina Descarboxilasa/antagonistas & inhibidores , Desoxiadenosinas/farmacología , Inhibidores Enzimáticos/farmacología , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Tripanosomiasis Africana/tratamiento farmacológico , Adenosilmetionina Descarboxilasa/metabolismo , Animales , Desoxiadenosinas/síntesis química , Desoxiadenosinas/química , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Ratones , Conformación Molecular , Pruebas de Sensibilidad Parasitaria , Relación Estructura-Actividad , Tripanocidas/síntesis química , Tripanocidas/química
3.
Bioorg Med Chem Lett ; 24(9): 2168-72, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24685543

RESUMEN

Follicle-stimulating hormone (FSH), acting on its receptor (FSHR), plays a pivotal role in the stimulation of follicular development and maturation. Multiple injections of protein formulations are used during clinical protocols for ovulation induction and for in vitro fertilization that are followed by a selection of assisted reproductive technologies. In order to increase patient convenience and compliance several research groups have searched for orally bioavailable FSH mimetics for innovative fertility medicines. We report here the discovery of a series of substituted benzamides as positive allosteric modulators (PAM) targeting FSHR. Optimization of this series has led to enhanced activity in primary rat granulosa cells, as well as remarkable selectivity against the closely related luteinizing hormone receptor (LHR) and thyroid stimulating hormone receptor (TSHR). Two modulators, 9j and 9k, showed promising in vitro and pharmacokinetic profiles.


Asunto(s)
Regulación Alostérica/efectos de los fármacos , Benzamidas/química , Benzamidas/farmacología , Hormona Folículo Estimulante/metabolismo , Animales , Células CHO , Células Cultivadas , Cricetulus , Femenino , Hormona Folículo Estimulante/agonistas , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Humanos , Ratas
4.
J Med Chem ; 64(19): 14603-14619, 2021 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-34596404

RESUMEN

Herein, we report the discovery of a novel class of quinazoline carboxamides as dual p70S6k/Akt inhibitors for the treatment of tumors driven by alterations to the PI3K/Akt/mTOR (PAM) pathway. Through the screening of in-house proprietary kinase library, 4-benzylamino-quinazoline-8-carboxylic acid amide 1 stood out, with sub-micromolar p70S6k biochemical activity, as the starting point for a structurally enabled p70S6K/Akt dual inhibitor program that led to the discovery of M2698, a dual p70S6k/Akt inhibitor. M2698 is kinase selective, possesses favorable physical, chemical, and DMPK profiles, is orally available and well tolerated, and displayed tumor control in multiple in vivo studies of PAM pathway-driven tumors.


Asunto(s)
Neoplasias , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas c-akt , Proteínas Quinasas S6 Ribosómicas 70-kDa , Animales , Humanos , Línea Celular Tumoral , Ensayos Analíticos de Alto Rendimiento , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Quinasas S6 Ribosómicas 70-kDa/antagonistas & inhibidores , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Transducción de Señal/efectos de los fármacos , Estereoisomerismo , Relación Estructura-Actividad , Serina-Treonina Quinasas TOR/efectos de los fármacos
5.
ACS Infect Dis ; 3(7): 512-526, 2017 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-28350440

RESUMEN

Human African trypanosomiasis (HAT) is a fatal infectious disease caused by the eukaryotic pathogen Trypanosoma brucei (Tb). Available treatments are difficult to administer and have significant safety issues. S-Adenosylmethionine decarboxylase (AdoMetDC) is an essential enzyme in the parasite polyamine biosynthetic pathway. Previous attempts to develop TbAdoMetDC inhibitors into anti-HAT therapies failed due to poor brain exposure. Here, we describe a large screening campaign of two small-molecule libraries (∼400,000 compounds) employing a new high-throughput (∼7 s per sample) mass spectrometry-based assay for AdoMetDC activity. As a result of primary screening, followed by hit confirmation and validation, we identified 13 new classes of reversible TbAdoMetDC inhibitors with low-micromolar potency (IC50) against both TbAdoMetDC and T. brucei parasite cells. The majority of these compounds were >10-fold selective against the human enzyme. Importantly, compounds from four classes demonstrated high propensity to cross the blood-brain barrier in a cell monolayer assay. Biochemical analysis demonstrated that compounds from eight classes inhibited intracellular TbAdoMetDC in the parasite, although evidence for a secondary off-target component was also present. The discovery of several new TbAdoMetDC inhibitor chemotypes provides new hits for lead optimization programs aimed to deliver a novel treatment for HAT.


Asunto(s)
Adenosilmetionina Descarboxilasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Ensayos Analíticos de Alto Rendimiento , Proteínas Protozoarias/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Adenosilmetionina Descarboxilasa/genética , Adenosilmetionina Descarboxilasa/metabolismo , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Perros , Inhibidores Enzimáticos/química , Expresión Génica , Humanos , Cinética , Células de Riñón Canino Madin Darby , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Modelos Biológicos , Pruebas de Sensibilidad Parasitaria , Permeabilidad , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-Actividad , Tripanocidas/química , Trypanosoma brucei brucei/enzimología , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/crecimiento & desarrollo
6.
Oecologia ; 87(1): 80-85, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28313355

RESUMEN

We conducted a controlled crossing experiment to examine the effects of maternal and paternal parentage, the size of the pollen load, and prior fruit production on the proportion of flowers that set fruit, seed number per fruit and seed weight in a natural population of Campanula americana. Effects due to the maternal parent were large for all measures of fruit and seed production, while the paternal parent had a significant effect only upon mean seed weight. As the number of prior fruits on the maternal plant increased the probability that a flower would produce a mature fruit, the number of seeds per fruit, and total seed weight per fruit all decreased. We found no effect of the size of the pollen loads used in this study on fruit or seed production. These results are consistent with those of other studies that suggest in natural plant populations maternal effects, especially environmental maternal effects, can have an overwhelming effect on fruit and seed production and on seed characteristics.

8.
Evolution ; 46(6): 1731-1739, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28567761

RESUMEN

To examine the effects of maternal and paternal parentage and the size of the pollen load on seed size and weight and on progeny performance we conducted a controlled crossing experiment using a natural population of Campanula americana. We found that seed size was positively correlated with early seedling performance for all but one of traits we measured (days to emergence), but was not significantly correlated with any of the later vegetative measures or reproductive output. We detected significant effects due to the maternal parent for the vegetative traits days to emergence, days to first leaf, and final plant height, as well as total seed weight, and mean seed weight per fruit. Significant paternal effects were found for all of the seedling traits except number of leaves after vernalization. The progeny from fruits receiving high pollen loads significantly outperformed the progeny from fruits receiving low pollen loads for the traits days to first and second leaf, numbers of leaves after vernalization, and days to first flower. These results not only demonstrate the importance of parentage and seed weight on progeny performance, but also indicate that variations in the size of the pollen load may be important in seedling establishment in natural populations.

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