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1.
J Obstet Gynecol Neonatal Nurs ; 53(3): 285-295, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38281725

RESUMEN

OBJECTIVE: To determine whether lactate levels were associated with maternal infection and infection-related outcomes in the antepartum, intrapartum, and early postpartum periods. DESIGN: Retrospective, observational cohort. SETTING: Eleven hospitals from a single health system. PARTICIPANTS: Women (N = 783) with at least one lactate and blood culture test for obstetric sepsis screening in the antepartum period (n = 154), intrapartum period (n = 348), and early postpartum period (n = 281) from January 2, 2018, to October 21, 2020. METHODS: We reported the proportion of participants with adverse outcomes by lactate cut points (≤2.0 and >2.0 mmol/L). We used logistic regression to model the association of infection-related outcomes with lactate levels and calculated receiver operating characteristic curves. RESULTS: Lactate was associated with bacteremia among participants in the antepartum period (odds ratio [OR] = 1.60, 95% confidence interval [CI] [1.00, 2.56]) but not among participants in the intrapartum and early postpartum periods. Higher lactate levels were significantly associated with a composite measure of infection-related outcomes (OR = 1.41, 95% CI [1.14, 1.81]), with no differential association by antepartum, intrapartum, or early postpartum periods. Lactate levels were positively associated with intraamniotic infection in the antepartum period (OR = 1.57, 95% CI [1.06, 1.81]) but not in the intrapartum period. The receiver operating characteristic curve indicated that the lactate threshold of 2.0 mmol/L has poor sensitivity. Overall, participants in the antepartum period had lower lactate values than participants in the intrapartum and early postpartum periods. CONCLUSION: Lactate levels were not consistently associated with infection-related measures across all periods. We suggest caution when interpreting lactate levels when sepsis is suspected.


Asunto(s)
Ácido Láctico , Periodo Periparto , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Adulto , Ácido Láctico/sangre , Periodo Periparto/sangre , Complicaciones Infecciosas del Embarazo/sangre , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/diagnóstico , Estudios de Cohortes , Sepsis/sangre , Sepsis/diagnóstico , Sepsis/epidemiología
2.
Foodborne Pathog Dis ; 19(11): 725-743, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36367547

RESUMEN

Listeria monocytogenes is a relatively rare but highly pathogenic bacterium that can cause foodborne infections. In the United States there are ∼1600 cases per year, 94% of which result in hospitalizations and 20% in deaths. Per-case burden is high because the disease also causes serious complications, including sepsis, encephalitis, meningitis, miscarriage, and stillbirth. The disease burden of L. monocytogenes is underestimated because some of these acute complications can also result in long-term outcomes. In this article, we conducted a scoping review of L. monocytogenes complications and longer term outcomes from articles published between 2000 and 2018. Search terms were developed for four major databases (PubMed, Scopus, Web of Science, and Embase) as well as gray literature and hand searches of review articles. We follow standard scoping review methodology and assessment. Out of 10,618 unique articles originally identified, 115 articles were included, representing 49 unique outcomes. The majority of studies were cohort designs (n = 67) and conducted in the United States or Europe (n = 98). Four major outcome groupings were death, neurological disorders, sepsis, and congenital infection. This study identifies substantial research on the common acute complications of L. monocytogenes and few long-term consequences of L. monocytogenes. We identify the need for additional studies to determine the longer term impacts of these acute complications.


Asunto(s)
Listeria monocytogenes , Listeriosis , Sepsis , Humanos , Estados Unidos/epidemiología , Listeriosis/complicaciones , Listeriosis/epidemiología , Sepsis/epidemiología , Europa (Continente)
3.
Foodborne Pathog Dis ; 19(2): 104-114, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34883025

RESUMEN

Listeriosis is a rare bacterial infection associated with foodborne illness that can result in septicemia, a serious acute outcome. Sepsis is responsible for one in three deaths during hospitalization. The objective of this study was to conduct a systematic review and meta-analysis to estimate the proportion of Listeria monocytogenes infections resulting in septicemia. PubMed, Embase, Scopus, and Web of Science were searched from January 1, 2000, to April 1, 2018, for epidemiological studies that assessed studies focusing on L. monocytogenes infections with the outcome of septicemia. Articles in English, Spanish, and Portuguese using case-control, cohort, or outbreak studies reporting measures of association between L. monocytogenes and septicemia were included. Bias and heterogeneity were assessed using univariate meta-regression for region, sample size, study design, and report method. Nineteen articles were eligible for inclusion post-screening, the majority of which were conducted in Europe (n = 15); utilized a retrospective cohort design (n = 16); and collected data via routine or laboratory surveillance methods (n = 10). Prevalence of sepsis ranged from 4.2% to 100% among study populations of 6 to 1374 individuals. Overall, the proportion of listeriosis cases that developed sepsis was 46% (95% confidence interval [CI] 31.0-61.0%); for neonatal cases, 21.3% (95% CI 11.0-31.6%); and for maternal and neonatal cases, 18.8% (95% CI 10.7-26.8%). The heterogeneity was high for overall and group meta-analyses, but it could not be explained by the subanalyses for the overall proportion, whereas for neonatal, and neonatal and maternal cases combined, China had a significantly lower proportion than Europe and the United States. Septicemia following L. monocytogenes infection is a severe acute complication with 31-61% rate found overall; however, greater delineation of demographic data is needed to determine important risk factors. Future research should aim to address the gaps in knowledge in the long-term outcomes of sepsis from L. monocytogenes infection, and whether these outcomes differ from those due to other infections.


Asunto(s)
Enfermedades Transmitidas por los Alimentos , Listeria monocytogenes , Listeriosis , Sepsis , Enfermedades Transmitidas por los Alimentos/microbiología , Humanos , Recién Nacido , Listeriosis/microbiología , Estudios Retrospectivos , Sepsis/epidemiología
4.
Foodborne Pathog Dis ; 18(10): 687-701, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34292763

RESUMEN

Previous economic estimates of infection with Toxoplasma gondii and chronic sequelae following infection lack sufficient data to establish the true burden of disease and its chronic sequelae. This scoping review aims to fill this gap by updating existing literature regarding the development of postinfectious sequelae following T. gondii infection. Literature published between January 1, 2000, and November 6, 2018, in PubMed, EMBASE, and Scopus was searched for a wide range of postinfectious sequelae and economic estimate terms. This scoping review includes summaries from the 108 articles covering 5 main groupings of outcomes (categories are not exclusive) including vision disorders (n = 58), psychological and mental health disorders (n = 27), neurological disorders (n = 17), fetal death and infection (n = 15), and hearing loss (n = 6), as well as a description of other outcomes reported. While the majority of the included studies assessed the incidence of these outcomes postinfection, very few followed participants long-term. These prospective studies are needed to understand the true burden of postinfectious sequelae over the life course, particularly because congenital infection with Toxoplasma can lead to severe outcomes for newborns. This scoping review can be used as an important resource for other researchers wishing to conduct future systematic reviews and meta-analyses, as well as for policy makers interested in developing guidance for public and health care partners.


Asunto(s)
Toxoplasma , Humanos , Incidencia , Recién Nacido
5.
J Obstet Gynecol Neonatal Nurs ; 50(2): 154-166, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33493464

RESUMEN

OBJECTIVE: To describe patterns of use of self-administered nitrous oxide (N2O) during labor and to determine if maternal and neonatal process and outcome measures differ for women who use N2O compared to women who do not use N2O. DESIGN: Retrospective, full-census, observational cohort. SETTING: An upper midwestern U.S., urban, 75-bed quaternary perinatal center with more than 5,000 annual births. PARTICIPANTS: The participants included two groups of women: 400 who used N2O during labor and a comparison group of 6,733 who met N2O eligibility but did not use N2O. METHODS: We used descriptive statistics to examine patterns of use of N2O during labor between January 2015 and March 2017. We examined associations of N2O with process (length of first and second stages of labor, time from hospital admission to birth, time from birth to hospital discharge, and total length of stay) and outcome measures (shoulder dystocia, instrumentation, vaginal lacerations, Apgar scores at 5 minutes, nursery disposition) using multivariate linear, logistic, and ordinal regression models. RESULTS: Three percent (12/400) of women who used N2O discontinued because of side effects. Among participants with vaginal births who used N2O, 17.6% (62/352) used N2O as the only form of pain medication during labor. We found no significant differences in maternal and neonatal outcome measures between the two groups. Among the process measures examined, we found a mean 2-hour-longer time from admission to birth and total length of stay in the N2O group (p < .05) compared to the non-N2O group. CONCLUSION: Most participants who used N2O (290/352, 82.3%) transitioned to other pain modalities during labor. Maternal and neonatal process and outcome measures were comparable relative to other pain management modalities, with the exception of longer time durations for two measures.


Asunto(s)
Analgesia , Óxido Nitroso , Cesárea , Femenino , Humanos , Óxido Nitroso/efectos adversos , Evaluación de Resultado en la Atención de Salud , Embarazo , Estudios Retrospectivos
6.
Blood ; 135(26): 2388-2401, 2020 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-32232483

RESUMEN

A goal in precision medicine is to use patient-derived material to predict disease course and intervention outcomes. Here, we use mechanistic observations in a preclinical animal model to design an ex vivo platform that recreates genetic susceptibility to T-cell-mediated damage. Intestinal graft-versus-host disease (GVHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation. We found that intestinal GVHD in mice deficient in Atg16L1, an autophagy gene that is polymorphic in humans, is reversed by inhibiting necroptosis. We further show that cocultured allogeneic T cells kill Atg16L1-mutant intestinal organoids from mice, which was associated with an aberrant epithelial interferon signature. Using this information, we demonstrate that pharmacologically inhibiting necroptosis or interferon signaling protects human organoids derived from individuals harboring a common ATG16L1 variant from allogeneic T-cell attack. Our study provides a roadmap for applying findings in animal models to individualized therapy that targets affected tissues.


Asunto(s)
Enfermedad Injerto contra Huésped/prevención & control , Enfermedades Intestinales/prevención & control , Organoides , Linfocitos T/inmunología , Acrilamidas/farmacología , Animales , Autofagia , Proteínas Relacionadas con la Autofagia/deficiencia , Proteínas Relacionadas con la Autofagia/genética , Trasplante de Médula Ósea/efectos adversos , Técnicas de Cocultivo , Colon/anomalías , Femenino , Predisposición Genética a la Enfermedad , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/patología , Humanos , Imidazoles/farmacología , Indoles/farmacología , Enfermedades Inflamatorias del Intestino/patología , Enfermedades Intestinales/inmunología , Enfermedades Intestinales/patología , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Necroptosis/efectos de los fármacos , Nitrilos , Células de Paneth/patología , Medicina de Precisión , Pirazoles/farmacología , Pirimidinas , Quimera por Radiación , Proteína Serina-Treonina Quinasas de Interacción con Receptores/deficiencia , Sulfonamidas/farmacología , Linfocitos T/trasplante
7.
J Med Chem ; 62(10): 5096-5110, 2019 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-31013427

RESUMEN

RIP1 kinase regulates necroptosis and inflammation and may play an important role in contributing to a variety of human pathologies, including inflammatory and neurological diseases. Currently, RIP1 kinase inhibitors have advanced into early clinical trials for evaluation in inflammatory diseases such as psoriasis, rheumatoid arthritis, and ulcerative colitis and neurological diseases such as amyotrophic lateral sclerosis and Alzheimer's disease. In this paper, we report on the design of potent and highly selective dihydropyrazole (DHP) RIP1 kinase inhibitors starting from a high-throughput screen and the lead-optimization of this series from a lead with minimal rat oral exposure to the identification of dihydropyrazole 77 with good pharmacokinetic profiles in multiple species. Additionally, we identified a potent murine RIP1 kinase inhibitor 76 as a valuable in vivo tool molecule suitable for evaluating the role of RIP1 kinase in chronic models of disease. DHP 76 showed efficacy in mouse models of both multiple sclerosis and human retinitis pigmentosa.


Asunto(s)
Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Proteínas de Complejo Poro Nuclear/antagonistas & inhibidores , Pirazoles/síntesis química , Pirazoles/farmacología , Proteínas de Unión al ARN/antagonistas & inhibidores , Animales , Disponibilidad Biológica , Línea Celular , Enfermedad Crónica , Diseño de Fármacos , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Inhibidores Enzimáticos/farmacocinética , Haplorrinos , Ensayos Analíticos de Alto Rendimiento , Humanos , Ratones , Ratones Endogámicos C57BL , Modelos Moleculares , Esclerosis Múltiple/tratamiento farmacológico , Pirazoles/farmacocinética , Ratas , Retinitis Pigmentosa/tratamiento farmacológico , Relación Estructura-Actividad
8.
Immunity ; 49(1): 42-55.e6, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-30021146

RESUMEN

The execution of shock following high dose E. coli lipopolysaccharide (LPS) or bacterial sepsis in mice required pro-apoptotic caspase-8 in addition to pro-pyroptotic caspase-11 and gasdermin D. Hematopoietic cells produced MyD88- and TRIF-dependent inflammatory cytokines sufficient to initiate shock without any contribution from caspase-8 or caspase-11. Both proteases had to be present to support tumor necrosis factor- and interferon-ß-dependent tissue injury first observed in the small intestine and later in spleen and thymus. Caspase-11 enhanced the activation of caspase-8 and extrinsic cell death machinery within the lower small intestine. Neither caspase-8 nor caspase-11 was individually sufficient for shock. Both caspases collaborated to amplify inflammatory signals associated with tissue damage. Therefore, combined pyroptotic and apoptotic signaling mediated endotoxemia independently of RIPK1 kinase activity and RIPK3 function. These observations bring to light the relevance of tissue compartmentalization to disease processes in vivo where cytokines act in parallel to execute diverse cell death pathways.


Asunto(s)
Caspasa 8/metabolismo , Caspasas/metabolismo , Infecciones por Escherichia coli/enzimología , Infecciones por Escherichia coli/fisiopatología , Choque Séptico/enzimología , Choque Séptico/fisiopatología , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Caspasa 8/genética , Caspasas/genética , Caspasas Iniciadoras , Células Cultivadas , Femenino , Inflamación/metabolismo , Inflamación/patología , Factor 3 Regulador del Interferón/genética , Interferón beta/sangre , Interferón beta/metabolismo , Intestino Delgado/patología , Péptidos y Proteínas de Señalización Intracelular , Lipopolisacáridos/toxicidad , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Unión a Fosfato , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Transducción de Señal , Bazo/patología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/metabolismo
9.
Ciudad Autónoma de Buenos Aires; Argentina. Ministerio de Salud de la Nación. Dirección de Investigación en Salud; mayo 2017. 1-21 p. tab.
No convencional en Español | ARGMSAL, BINACIS | ID: biblio-1396673

RESUMEN

La Argentina es un gran productor de alimentos a nivel mundial, lo que también implica un alto uso de agroquímicos, los cuales poseen diferentes grados de toxicidad. Se realizó una investigación cualitativa con el objetivo de describir y comprender el impacto en la salud del uso de agroquímicos por parte de agricultores familiares y trabajadores rurales en el contexto del trabajo realizado por los sistemas de salud y extensión rural en localidades seleccionadas de las provincias de Buenos Aires, Corrientes, Formosa, Misiones y Santiago del Estero. Se realizaron 77 entrevistas a extensionistas, agentes del sistema de salud y agricultores o trabajadores rurales divididas en las 5 localidades, las cuales se analizaron con el software Atlas Ti. Los resultados muestran que en la mayoría de los casos los agroquímicos se compran, almacenan y aplican de manera insegura, generándose graves riesgos para la salud. Se trata de un problema complejo que no puede ser reducido a prácticas individuales de los agricultores. El sistema local de salud y el de extensión trabajan de manera descoordinada y no cuentan con los conocimientos y las herramientas necesarias para abordar el problema. Entre los factores que contribuyen con su mantenimiento se destacan la tendencia de agricultores y trabajadores rurales a desconocer o minimizar la toxicidad de los agroquímicos, el subregistro de casos de intoxicación, los problemas para un diagnóstico diferencial, la falta de programas o estrategias para formar a los agentes públicos la temática y la escasez de recursos humanos


Asunto(s)
Plaguicidas/envenenamiento , Intoxicación , Trabajadores Rurales , Agroquímicos , Agroquímicos/envenenamiento , Servicios de Salud Rural , Enfermedades de los Trabajadores Agrícolas
10.
J Med Chem ; 60(4): 1247-1261, 2017 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-28151659

RESUMEN

RIP1 regulates necroptosis and inflammation and may play an important role in contributing to a variety of human pathologies, including immune-mediated inflammatory diseases. Small-molecule inhibitors of RIP1 kinase that are suitable for advancement into the clinic have yet to be described. Herein, we report our lead optimization of a benzoxazepinone hit from a DNA-encoded library and the discovery and profile of clinical candidate GSK2982772 (compound 5), currently in phase 2a clinical studies for psoriasis, rheumatoid arthritis, and ulcerative colitis. Compound 5 potently binds to RIP1 with exquisite kinase specificity and has excellent activity in blocking many TNF-dependent cellular responses. Highlighting its potential as a novel anti-inflammatory agent, the inhibitor was also able to reduce spontaneous production of cytokines from human ulcerative colitis explants. The highly favorable physicochemical and ADMET properties of 5, combined with high potency, led to a predicted low oral dose in humans.


Asunto(s)
Antiinflamatorios/química , Antiinflamatorios/farmacología , Colitis Ulcerosa/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteína Serina-Treonina Quinasas de Interacción con Receptores/antagonistas & inhibidores , Animales , Benzazepinas/química , Benzazepinas/farmacología , Colitis Ulcerosa/inmunología , Citocinas/inmunología , Perros , Haplorrinos , Humanos , Inflamación/inmunología , Ratones , Simulación del Acoplamiento Molecular , Conejos , Ratas , Proteína Serina-Treonina Quinasas de Interacción con Receptores/inmunología , Porcinos , Porcinos Enanos , Factor de Necrosis Tumoral alfa/inmunología
11.
J Med Chem ; 59(5): 2163-78, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26854747

RESUMEN

The recent discovery of the role of receptor interacting protein 1 (RIP1) kinase in tumor necrosis factor (TNF)-mediated inflammation has led to its emergence as a highly promising target for the treatment of multiple inflammatory diseases. We screened RIP1 against GSK's DNA-encoded small-molecule libraries and identified a novel highly potent benzoxazepinone inhibitor series. We demonstrate that this template possesses complete monokinase selectivity for RIP1 plus unique species selectivity for primate versus nonprimate RIP1. We elucidate the conformation of RIP1 bound to this benzoxazepinone inhibitor driving its high kinase selectivity and design specific mutations in murine RIP1 to restore potency to levels similar to primate RIP1. This series differentiates itself from known RIP1 inhibitors in combining high potency and kinase selectivity with good pharmacokinetic profiles in rodents. The favorable developability profile of this benzoxazepinone template, as exemplified by compound 14 (GSK'481), makes it an excellent starting point for further optimization into a RIP1 clinical candidate.


Asunto(s)
ADN/química , Isoxazoles/farmacología , Oxazepinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteína Serina-Treonina Quinasas de Interacción con Receptores/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Línea Celular Tumoral , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Células HT29 , Humanos , Isoxazoles/síntesis química , Isoxazoles/química , Ratones , Modelos Moleculares , Estructura Molecular , Oxazepinas/síntesis química , Oxazepinas/química , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-Actividad , Células U937
12.
Bioorg Med Chem Lett ; 25(14): 2739-43, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26022841

RESUMEN

Nod-like receptors (NLRs) are cytoplasmic pattern recognition receptors that are promising targets for the development of anti-inflammatory therapeutics. Drug discovery efforts targeting NLRs have been hampered by their inherent tendency to form aggregates making protein generation and the development of screening assays very challenging. Herein we report the results of an HTS screen of NLR family member NLRP1 (NLR family, pyrin domain-containing 1) which was achieved through the large scale generation of recombinant GST-His-Thrombin-NLRP1 protein. The screen led to the identification of a diverse set of ATP competitive inhibitors with micromolar potencies. Activity of these hits was confirmed in a FP binding assay, and two homology models were employed to predict the possible binding mode of the leading series and facilitate further lead-optimization. These results highlight a promising strategy for the identification of inhibitors of NLR family members which are rapidly emerging as key drivers of inflammation in human disease.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Adenosina Trifosfato/química , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Inflamasomas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adenosina Trifosfato/metabolismo , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Sitios de Unión , Unión Competitiva , Ensayos Analíticos de Alto Rendimiento , Humanos , Simulación del Acoplamiento Molecular , Proteínas NLR , Unión Proteica , Estructura Terciaria de Proteína , Pirazoles/química , Pirazoles/metabolismo , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Relación Estructura-Actividad
13.
Neuroimage ; 81: 8-14, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23664942

RESUMEN

UNLABELLED: Traditional interpretation of rCBF SPECT data is of a qualitative nature and is dependent on the observer's understanding of the normal distribution of the tracer. The use of a normal database in quantitative regional analysis facilitates the detection of functional abnormality in individual and group studies by accounting for inter-subject variability. The ability to simulate realistic images would allow various important areas related to the use of normal databases to be studied. These include the optimisation of the detection of abnormal blood flow and the portability of normal databases between gamma camera systems. To investigate this further we have constructed a hardware phantom and scanned various configurations of radioactive brain patterns and simulated skull configurations. METHODS: A subresolution sandwich phantom was constructed with a simulated skull which was assembled using a high-resolution segmented MR scan printed with a (99m)TcO4 - mixture and scanned using a double-headed gamma camera with parallel-hole collimators. Various different grey-to-white matter (GM:WM) ratios and aluminium simulated skull configurations were used. A single difference measure between the phantom data and a control database mean image was used for optimisation. The realism of phantom data was assessed using statistical parametric mapping (SPM) and ROI analysis. RESULTS: Optimisation was achieved with a range of WM:GM ratios from 1.9 to 2.4:1 with various simulated skull configurations. CONCLUSION: The ability to simulate realistic HMPAO SPECT scans has been demonstrated using a subresolution sandwich phantom. Further work, involving scanning the optimised phantom on different gamma camera systems and comparison with camera-specific normal databases should further refine the phantom configuration.


Asunto(s)
Mapeo Encefálico/métodos , Fantasmas de Imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Circulación Cerebrovascular/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos , Exametazima de Tecnecio Tc 99m
14.
J Bone Miner Res ; 28(7): 1653-65, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23456892

RESUMEN

Rosiglitazone (RSG) is an antidiabetic drug that has been associated with increased peripheral fractures, primarily in postmenopausal women. In this report, we investigated the underlying mechanisms of RSG-associated bone loss in ovariectomized (OVX) rats and determined whether changes in bone parameters associated with RSG administration are reversible on treatment cessation or preventable by coadministration with an antiresorptive agent. Nine-month-old Sprague-Dawley rats underwent OVX or sham operation. Sham-operated rats received oral vehicle only; OVX animals were randomized to receive vehicle, RSG, alendronate (ALN), or RSG plus ALN for 12 weeks. All treatment started the day after ovariectomy. After the 12-week treatment period, the OVX and RSG groups also underwent an 8-week treatment-free recovery period. Bone densitometry measurements, bone turnover markers, biomechanical testing, and histomorphometric analysis were conducted. Microcomputed tomography was also used to investigate changes in microarchitecture. RSG significantly increased deoxypyridinoline levels compared with OVX. Significant exacerbation of OVX-induced loss of bone mass, strength, and microarchitectural deterioration was observed in RSG-treated OVX animals compared with OVX controls. These effects were observed predominantly at sites rich in trabecular bone, with less pronounced effects in cortical bone. Coadministration of RSG and ALN prevented the bone loss associated with RSG treatment. Following cessation of RSG treatment, effects on bone mass and strength showed evidence of reversal. Thus, treatment of OVX rats with RSG results in loss of bone mass and strength, primarily at sites rich in trabecular bone, mainly due to increased bone resorption. These effects can be prevented by concomitant treatment with ALN and may be reversed following discontinuation of RSG.


Asunto(s)
Alendronato/farmacología , Conservadores de la Densidad Ósea/farmacología , Densidad Ósea/efectos de los fármacos , Hipoglucemiantes/farmacología , Osteoporosis Posmenopáusica/tratamiento farmacológico , Tiazolidinedionas/farmacología , Animales , Femenino , Fracturas Óseas/etiología , Fracturas Óseas/metabolismo , Humanos , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/metabolismo , Ovariectomía , Ratas , Ratas Sprague-Dawley , Rosiglitazona , Factores de Tiempo , Microtomografía por Rayos X
15.
ACS Med Chem Lett ; 4(12): 1238-43, 2013 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-24900635

RESUMEN

Potent inhibitors of RIP1 kinase from three distinct series, 1-aminoisoquinolines, pyrrolo[2,3-b]pyridines, and furo[2,3-d]pyrimidines, all of the type II class recognizing a DLG-out inactive conformation, were identified from screening of our in-house kinase focused sets. An exemplar from the furo[2,3-d]pyrimidine series showed a dose proportional response in protection from hypothermia in a mouse model of TNFα induced lethal shock.

16.
Bone ; 46(2): 534-42, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19786130

RESUMEN

Daily subcutaneous administration of exogenous parathyroid hormone (PTH) promotes bone formation in patients with osteoporosis. Here we describe two novel, short-acting calcium-sensing receptor antagonists (SB-423562 and its orally bioavailable precursor, SB-423557) that elicit transient PTH release from the parathyroid gland in several preclinical species and in humans. In an ovariectomized rat model of bone loss, daily oral administration of SB-423557 promoted bone formation and improved parameters of bone strength at lumbar spine, proximal tibia and midshaft femur. Chronic administration of SB-423557 did not increase parathyroid cell proliferation in rats. In healthy human volunteers, single doses of intravenous SB-423562 and oral SB-423557 elicited transient elevations of endogenous PTH concentrations in a profile similar to that observed with subcutaneously administered PTH. Both agents were well tolerated in humans. Transient increases in serum calcium, an expected effect of increased parathyroid hormone concentrations, were observed post-dose at the higher doses of SB-423557 studied. These data constitute an early proof of principle in humans and provide the basis for further development of this class of compound as a novel, orally administered bone-forming treatment for osteoporosis.


Asunto(s)
Etanolaminas/farmacología , Naftalenos/farmacología , Osteogénesis/efectos de los fármacos , Hormona Paratiroidea/sangre , Fenilpropionatos/farmacología , Receptores Sensibles al Calcio/antagonistas & inhibidores , Administración Oral , Animales , Huesos/citología , Huesos/efectos de los fármacos , Calcio/sangre , Proliferación Celular/efectos de los fármacos , Perros , Esquema de Medicación , Etanolaminas/administración & dosificación , Etanolaminas/química , Etanolaminas/farmacocinética , Haplorrinos , Humanos , Masculino , Naftalenos/administración & dosificación , Naftalenos/química , Naftalenos/farmacocinética , Tamaño de los Órganos/efectos de los fármacos , Ovariectomía , Glándulas Paratiroides/citología , Glándulas Paratiroides/efectos de los fármacos , Fenilpropionatos/administración & dosificación , Fenilpropionatos/química , Fenilpropionatos/farmacocinética , Ratas , Ratas Sprague-Dawley
17.
J Med Chem ; 52(21): 6599-605, 2009 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-19821575

RESUMEN

When administered as a single agent to rats, the previously reported calcium receptor antagonist 3 elicited a sustained elevation of plasma PTH resulting in no increase in overall bone mineral density. The lack of a bone building effect for analogue 3 was attributed to the large volume of distribution (V(dss)(rat) = 11 L/kg), producing a protracted plasma PTH profile. Incorporation of a carboxylic acid functionality into the amino alcohol template led to the identification of 12 with a lower volume of distribution (V(dss)(12) = 1.18 L/kg) and a shorter half-life. The zwitterionic nature of antagonist 12 necessitated the utility of an ester prodrug approach to increase overall permeability. Antagonist 12 elicited a rapid and transient increase in circulating levels of PTH following oral dosing of the ester prodrug 11 in the dog. The magnitude and duration of the increases in plasma levels of PTH would be expected to stimulate new bone formation.


Asunto(s)
Amino Alcoholes/síntesis química , Hormona Paratiroidea/sangre , Fenilpropionatos/síntesis química , Profármacos/síntesis química , Propanolaminas/síntesis química , Receptores Sensibles al Calcio/antagonistas & inhibidores , Administración Oral , Amino Alcoholes/farmacocinética , Amino Alcoholes/farmacología , Animales , Disponibilidad Biológica , Calcio/metabolismo , Línea Celular , Citoplasma/metabolismo , Perros , Ésteres , Humanos , Hormona Paratiroidea/metabolismo , Permeabilidad , Fenilpropionatos/farmacocinética , Fenilpropionatos/farmacología , Profármacos/farmacocinética , Profármacos/farmacología , Propanolaminas/farmacocinética , Propanolaminas/farmacología , Ensayo de Unión Radioligante , Ratas , Estereoisomerismo , Relación Estructura-Actividad
18.
PLoS One ; 4(8): e6523, 2009 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-19654868

RESUMEN

Estrogen may be involved in the development of prostate cancer. The association between genetic polymorphisms of estrogen receptors alpha (ESR1) and beta (ESR2) and prostate cancer risk was examined in a nested case-control study in Washington County, Maryland. Incident prostate cancer cases (n = 269) were matched to one or two controls (n = 440) by age, sex, race, and date of blood donation. Associations between estrogen receptor genotypes or dietary intake and the development of prostate cancer were examined in conditional logistic regression models. Results from this study showed that six single base-pair polymorphisms (SNPs) of ESR1 (rs1801132, rs2077647, rs746432, rs2273206, rs851982, rs2228480) and four SNPs of ESR2 (rs4986938, rs928554, rs8018687, rs number not available for ESR2 5696 bp 3' of STP A>G) were not significantly associated with prostate cancer risk, either by allelic or genotypic frequencies. However, an interactive association with BMI was observed in the relationship between prostate cancer risk and genotypes of ESR2 38 bp 3' of STP G>A (rs4986938) (p = 0.031). An interaction between intake level of phytoestrogen and genotypes of ESR1 Ex1-192G>C (rs746432) and between intake level of phytoestrogen and genotypes of ESR1 Ex8+229G>A (rs2228480) and risk of prostate cancer was observed (p = 0.0009 and p = 0.044, respectively). In conclusion, selected genetic polymorphisms of ESR1 and ESR2, overall, were not associated with prostate cancer risk. However, a variation in risk by BMI and phytoestrogen intake was implicated.


Asunto(s)
Receptor alfa de Estrógeno/genética , Receptor beta de Estrógeno/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Neoplasias de la Próstata/genética , Anciano , Índice de Masa Corporal , Femenino , Genotipo , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Fitoestrógenos/administración & dosificación
19.
Cardiovasc Res ; 81(2): 278-85, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19015136

RESUMEN

AIMS: Cathepsin K (CatK), an established drug target for osteoporosis, has been reported to be upregulated in atherosclerotic lesions. Due to its proteolytic activity, CatK may influence the atherosclerotic lesion composition and stability. In this study, we investigated the potential role of leucocyte CatK in atherosclerotic plaque remodelling. METHODS AND RESULTS: To assess the biological role of leucocyte CatK, we used the technique of bone marrow transplantation to selectively disrupt CatK in the haematopoietic system. Total bone marrow progenitor cells from CatK(+/+), CatK(+/-), and CatK(-/-) mice were transplanted into X-ray irradiated low-density lipoprotein receptor knockout (LDLr(-/-)) mice. The selective silencing of leucocyte CatK resulted in phenotypic changes in bone formation with an increased total bone mineral density in the CatK(-/-) chimeras and an effect of gene dosage. The absence of leucocyte CatK resulted in dramatically decreased collagen and increased macrophage content of the atherosclerotic lesions while lesion size was not affected. The atherosclerotic lesions also demonstrated less elastic lamina fragmentation and a significant increase in the apoptotic and necrotic area in plaques of mice transplanted with CatK(-/-) bone marrow. CONCLUSION: Leucocyte CatK is an important determinant of atherosclerotic plaque composition, vulnerability, and bone remodelling, rendering CatK an attractive target for pharmaceutical modulation in atherosclerosis and osteoporosis.


Asunto(s)
Aterosclerosis/etiología , Catepsinas/fisiología , Leucocitos/enzimología , Receptores de LDL/fisiología , Animales , Apolipoproteínas E/fisiología , Aterosclerosis/metabolismo , Densidad Ósea , Remodelación Ósea , Catepsina K , Colágeno/metabolismo , Femenino , Macrófagos/fisiología , Ratones
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