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1.
Mol Metab ; 10: 66-73, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29478918

RESUMEN

OBJECTIVES: Type 2 diabetes (T2D) is associated with chronic, low grade inflammation. Activation of the NLRP3 inflammasome and secretion of its target interleukin-1ß (IL-1ß) have been implicated in pancreatic ß cell failure in T2D. Specific targeting of the NLRP3 inflammasome to prevent pancreatic ß cell death could allow for selective T2D treatment without compromising all IL-1ß-associated immune responses. We hypothesized that treating a mouse model of T2D with MCC950, a compound that specifically inhibits NLRP3, would prevent pancreatic ß cell death, thereby preventing the onset of T2D. METHODS: Diabetic db/db mice were treated with MCC950 via drinking water for 8 weeks from 6 to 14 weeks of age, a period over which they developed pancreatic ß cell failure. We assessed metabolic parameters such as body composition, glucose tolerance, or insulin secretion over the course of the intervention. RESULTS: MCC950 was a potent inhibitor of NLRP3-induced IL-1ß in vitro and was detected at high levels in the plasma of treated db/db mice. Treatment of pre-diabetic db/db mice with MCC950, however, did not prevent pancreatic dysfunction and full onset of the T2D pathology. When examining the NLRP3 pathway in the pancreas of db/db mice, we could not detect an activation of this pathway nor increased levels of its target IL-1ß. CONCLUSIONS: NLRP3 driven-pancreatic IL-1ß inflammation does not play a key role in the pathogenesis of the db/db murine model of T2D.


Asunto(s)
Antiinflamatorios/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Células Secretoras de Insulina/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Animales , Antiinflamatorios/farmacología , Células Cultivadas , Diabetes Mellitus Tipo 2/metabolismo , Furanos , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Compuestos Heterocíclicos de 4 o más Anillos/uso terapéutico , Hipoglucemiantes/farmacología , Indenos , Células Secretoras de Insulina/efectos de los fármacos , Interleucina-1beta/metabolismo , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Sulfonamidas , Sulfonas/farmacología , Sulfonas/uso terapéutico
2.
Oncogene ; 36(24): 3417-3427, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28092670

RESUMEN

Recent evidence has implicated the transmembrane co-receptor neuropilin-1 (NRP1) in cancer progression. Primarily known as a regulator of neuronal guidance and angiogenesis, NRP1 is also expressed in multiple human malignancies, where it promotes tumor angiogenesis. However, non-angiogenic roles of NRP1 in tumor progression remain poorly characterized. In this study, we define NRP1 as an androgen-repressed gene whose expression is elevated during the adaptation of prostate tumors to androgen-targeted therapies (ATTs), and subsequent progression to metastatic castration-resistant prostate cancer (mCRPC). Using short hairpin RNA (shRNA)-mediated suppression of NRP1, we demonstrate that NRP1 regulates the mesenchymal phenotype of mCRPC cell models and the invasive and metastatic dissemination of tumor cells in vivo. In patients, immunohistochemical staining of tissue microarrays and mRNA expression analyses revealed a positive association between NRP1 expression and increasing Gleason grade, pathological T score, positive lymph node status and primary therapy failure. Furthermore, multivariate analysis of several large clinical prostate cancer (PCa) cohorts identified NRP1 expression at radical prostatectomy as an independent prognostic biomarker of biochemical recurrence after radiation therapy, metastasis and cancer-specific mortality. This study identifies NRP1 for the first time as a novel androgen-suppressed gene upregulated during the adaptive response of prostate tumors to ATTs and a prognostic biomarker of clinical metastasis and lethal PCa.


Asunto(s)
Neuropilina-1/genética , Neuropilina-1/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Neoplasias de la Próstata/tratamiento farmacológico , Regulación hacia Arriba , Antagonistas de Andrógenos/uso terapéutico , Línea Celular Tumoral , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Clasificación del Tumor , Metástasis de la Neoplasia , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/mortalidad , Análisis de Supervivencia
3.
Eur J Med Chem ; 120: 353-62, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27236016

RESUMEN

Diarrhoeal diseases caused by the intestinal parasites Giardia lamblia and Entamoeba histolytica constitute a major global health burden. Nitroimidazoles are first-line drugs for the treatment of giardiasis and amebiasis, with metronidazole 1 being the most commonly used drug worldwide. However, treatment failures in giardiasis occur in up to 20% of cases and development of resistance to metronidazole is of concern. We have re-examined 'old' nitroimidazoles as a foundation for the systematic development of next-generation derivatives. Using this approach, derivatisation of the nitroimidazole carboxamide scaffold provided improved antiparasitic agents. Thirty-three novel nitroimidazole carboxamides were synthesised and evaluated for activity against G. lamblia and E. histolytica. Several of the new compounds exhibited potent activity against G. lamblia strains, including metronidazole-resistant strains of G. lamblia (EC50 = 0.1-2.5 µM cf. metronidazole EC50 = 6.1-18 µM). Other compounds showed improved activity against E. histolytica (EC50 = 1.7-5.1 µM cf. metronidazole EC50 = 5.0 µM), potent activity against Trichomonas vaginalis (EC50 = 0.6-1.4 µM cf. metronidazole EC50 = 0.8 µM) and moderate activity against the intestinal bacterial pathogen Clostridium difficile (0.5-2 µg/mL, cf. metronidazole = 0.5 µg/mL). The new compounds had low toxicity against mammalian kidney and liver cells (CC50 > 100 µM), and selected antiparasitic hits were assessed for human plasma protein binding and metabolic stability in liver microsomes to demonstrate their therapeutic potential.


Asunto(s)
Antiparasitarios/farmacología , Nitroimidazoles/farmacología , Parásitos/efectos de los fármacos , Animales , Células Cultivadas , Resistencia a Medicamentos , Estabilidad de Medicamentos , Entamoeba histolytica/efectos de los fármacos , Giardia lamblia/efectos de los fármacos , Humanos , Trichomonas vaginalis/efectos de los fármacos
4.
Phytochemistry ; 58(8): 1235-8, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11738414

RESUMEN

Bioassay-guided fractionation of a CHCl(3) extract from the leaves of Ardisia teysmanniana Scheff. (Myrsinaceae) has led to the isolation of three new alkyldibenzoquinone derivatives that showed inhibitory activity in an in vitro assay for UDP-MurNac synthesis. The structures of ardisiaquinone G, H and I were established using MS and NMR spectroscopic methods.


Asunto(s)
Benzoquinonas/química , Primulaceae/química , Benzoquinonas/aislamiento & purificación , Hojas de la Planta/química
5.
J Bone Joint Surg Am ; 73(10): 1492-502, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1748698

RESUMEN

A review of the data on 684 fractures of the femur that had been treated with intramedullary nailing led to the identification of twenty-three patients who had had a fracture of the shaft of the femur with an accompanying ipsilateral supracondylar fracture (twelve patients, group I) or a concomitant ipsilateral intercondylar fracture (eleven patients, group II). The group-I fractures had been treated with interlocking nailing without supplemental fixation. In group II, ten fractures were stabilized with interlocking nailing and supplemental screw fixation and one, with interlocking nailing and a supplemental plate and screws. The average time to union for all fractures was nineteen weeks (range, twelve to thirty-six weeks), and the average duration of clinical and radiographic follow-up was thirty months (range, nine to fifty-nine months). In group I, alignment of the femur was within 5 degrees of normal in ten of the twelve fractures. In group II, seven intra-articular fractures healed in anatomical alignment, three had slight articular displacement (1.0 to 3.0 millimeters), and one had displacement of more than 3.0 millimeters. The average range of motion of the knee at the most recent follow-up was 0 to 120 degrees in group I and 0 to 115 degrees in group II. Two patients (both in group II) needed a reoperation for a previously unrecognized fracture of a femoral condyle in the coronal plane; post-traumatic arthritis developed in both. No patient in either group had loss of fixation or failure of the implant. We concluded that ipsilateral diaphyseal, supracondylar, and intercondylar fractures of the femur can be adequately stabilized with interlocking nailing and supplemental intercondylar screw fixation. The presence of a fracture in the coronal plane of a femoral condyle (AO type-B3 and type-C3 injuries) is a relative contraindication to the use of this technique.


Asunto(s)
Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas , Fracturas Cerradas/cirugía , Fracturas Abiertas/cirugía , Adolescente , Adulto , Anciano , Femenino , Fracturas del Fémur/diagnóstico por imagen , Humanos , Traumatismos de la Rodilla/complicaciones , Traumatismos de la Rodilla/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Radiografía , Cicatrización de Heridas
6.
J Parasitol ; 63(5): 831-4, 1977 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-915612

RESUMEN

Histochemical and thin layer chromatographic studies were made on neutral lipids of Cotylurus sp. (Trematoda) metacercariae obtained from Physa heterostropha snails and from adults grown in the upper ileum of the domestic chick. Oil Red O staining demonstrated neutral lipids in the intestinal lumina, eggs and vitellaria of adults, and the excretory system of metarcercariae. As determined by TLC, excysted metacercariae incubated in a non-nutrient salt solution excreted free fatty acids, sterols, and sterol esters into the medium. TLC analysis detected free sterols, free fatty acids and sterol esters in metacercariae and adullts, and triglycerides detected in adults were not found in metacercariae.


Asunto(s)
Pollos/parasitología , Lípidos/análisis , Caracoles/parasitología , Trematodos/análisis , Animales , Cromatografía en Capa Delgada , Ácidos Grasos no Esterificados/análisis , Histocitoquímica , Íleon/parasitología , Larva/análisis , Esteroles/análisis , Triglicéridos/análisis
7.
J Parasitol ; 63(6): 1041-5, 1977 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-592032

RESUMEN

Excysted metacercariae of Echinostoma revolutum cultured in vitro in the defined medium, NCTC 135 supplemented with 20% hens' egg yolk, doubled their mean relative body area and showed significant sucker growth within 14 days. Histochemical Oil Red O staining showed neutral fat mainly in the excretory system of excysted metacercariae and in adults grown in the domestic chick. In vitro cultured worms showed neutral fat in the intestine, parenchyma, and excretory system. As detected by TLC the major neutral lipid fractions were free fatty acids for excysted metacercariae; free sterols for adults grown in chicks; and triglycerides, free fatty acids, and free sterols for cultured worms. Excysted metacercariae excreted free fatty acids into a nonnutrient incubation medium, whereas cultured worms excreted diglycerides, triglycerides, and free fatty acids into the medium.


Asunto(s)
Echinostoma/análisis , Lípidos/análisis , Animales , Cromatografía en Capa Delgada , Medios de Cultivo , Echinostoma/crecimiento & desarrollo , Ácidos Grasos no Esterificados/análisis , Histocitoquímica , Caracoles/parasitología , Triglicéridos/análisis
8.
Percept Mot Skills ; 82(2): 527-30, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8724926

RESUMEN

The effectiveness of broad and narrow bandwidth feedback for learning a 2-segment timing task was tested over short-term (10-min.) and longer-term (2-day) retention intervals. The main finding was that bandwidth feedback groups deteriorated in accuracy across the retention tests, raising questions about the effectiveness of bandwidth feedback for longer-term learning.


Asunto(s)
Retroalimentación , Desempeño Psicomotor , Tiempo de Reacción , Retención en Psicología , Adulto , Femenino , Objetivos , Humanos , Conocimiento Psicológico de los Resultados , Masculino , Memoria a Corto Plazo
9.
Placenta ; 35(4): 260-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24559727

RESUMEN

INTRODUCTION: We have previously identified sex-specific differences in the fetal-placental response to cortisol. Our recent studies suggest that this differential response to cortisol is driven by differences in glucocorticoid receptor (GR) protein function rather than through changes in gene transcription or protein expression. METHODS: This study was designed to define whether the human placenta expresses different isoforms of the GR and whether expression was altered by fetal sex and maternal asthma. Asthma and non-asthma pregnant women were prospectively recruited at their first antenatal visit and placentae collected at delivery. Placental GR expression was examined in relation to maternal asthma, fetal sex and birthweight. RESULTS: Twelve specific bands for the GR were identified at molecular weights of 94, 91, 81, 74, 69, 68, 65, 60, 55, 50, 48 and 38 kDa. The 12 isoforms were localised to the placental trophoblast and expression varied in relation to cellular location in either the cytoplasm or nucleus, fetal sex, fetal size and the presence and absence of maternal asthma. CONCLUSION: This is the first study to identify the presence of several protein isoforms of the GR in the human placenta. The data suggest glucocorticoid resistance observed in male placentae may be mediated through increased GRß, GR A and GR P localisation to the nucleus. While female placentae may be more sensitive to cortisol in the presence of maternal asthma through a decrease in GRß and an enhancement GRα activity via an interaction with GRα D3 and GRα C.


Asunto(s)
Asma/metabolismo , Placenta/metabolismo , Complicaciones del Embarazo/metabolismo , Receptores de Glucocorticoides/metabolismo , Caracteres Sexuales , Corticoesteroides/uso terapéutico , Adulto , Asma/tratamiento farmacológico , Estudios de Casos y Controles , Femenino , Retardo del Crecimiento Fetal/metabolismo , Células HEK293 , Humanos , Hidrocortisona/sangre , Recién Nacido , Masculino , Fosforilación , Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Isoformas de Proteínas/metabolismo
13.
Opt Lett ; 12(3): 166-8, 1987 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-19738827

RESUMEN

An experimental investigation of a longitudinally excited Ca(+) discharge-recombination laser with an active volume of 1000 cm(3) is reported. Single-pulse output energy densities greater than 4 microJ/cm(3) at energy-conversion efficiencies of 0.05% have been obtained on the lambda373.7-nm transition for low-pulse-rate (1-Hz) operation at helium buffergas pressures up to 400 Torr. Mean powers greater 0.5 W have been obtained at 500 Hz in preliminary studies of high-pulse-rate operation.

14.
J Nat Prod ; 63(3): 393-5, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10757728

RESUMEN

Psammaplin A 11'-sulfate (3) and bisaprasin 11'-sulfate (4) have been isolated from the marine sponge Aplysinella rhax, along with the known psammaplin A (1). Their structures were determined on the basis of their spectroscopic data. Compounds 1 and 3 inhibited [(3)H]1,3-dipropyl-8-cyclopentylxanthine binding to rat-brain adenosine A(1) receptors.


Asunto(s)
Poríferos/química , Ésteres del Ácido Sulfúrico/aislamiento & purificación , Tirosina/análogos & derivados , Animales , Estructura Molecular , Ratas , Análisis Espectral , Ésteres del Ácido Sulfúrico/química , Tirosina/química , Tirosina/aislamiento & purificación
15.
J Mot Behav ; 27(3): 241-250, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12529235

RESUMEN

Describing and analyzing error for one-dimensional performance tasks is fairly straightforward, but suggestions for describing and analyzing error for two-dimensional performance tasks (e.g., marksmanship) are quite problematic. Specifically, imposing an arbitrary axis onto the two-dimensional work space, along which traditional one-dimensional measures can be computed and analyzed, yields measures of accuracy, bias, and consistency that are entirely dependent upon the choice of axis. The present contribution offers new measures and methods for describing and analyzing data from two-dimensional performances. Unlike the resu1ts from previous suggestions, the approaches described herein yield results that are completely independent of the axes used to quantify the individual two-dimensional trials. These new approaches are strongly related to well-established methods for describing and analyzing error for one-dimensional tasks.

16.
Med Pediatr Oncol ; 19(4): 265-8, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1647490

RESUMEN

Between 1970 and 1984, 31 children with biopsy-proven Wilms' tumor received nephrectomy, chemotherapy, and abdominal irradiation and were followed beyond skeletal maturity. Three patients (10%) developed late orthopedic abnormalities requiring intervention. Ten children received orthovoltage irradiation, and all cases requiring orthopedic intervention or developing a scoliotic curve of greater than 20 degrees were confined to this group, for a complication frequency of 50%. Those children who developed a significant late orthopedic abnormality (SLOA) as defined were treated to a higher median dose (2,890 cGy) and a larger field size (150 cm2) than those who did not (2,580 cGy and 120 cm2). Age at irradiation, sex, and initial stage of disease did not appear to influence the risk of developing an SLOA. No child who received megavoltage irradiation developed an SLOA despite treatment up to 4,000 cGy or to field sizes of 400 cm2. We conclude that modern radiotherapy techniques rarely lead to significant late orthopedic abnormalities previously associated with abdominal irradiation in children with Wilms' tumor.


Asunto(s)
Enfermedades del Desarrollo Óseo/etiología , Neoplasias Renales/radioterapia , Traumatismos por Radiación , Enfermedades de la Columna Vertebral/etiología , Tumor de Wilms/radioterapia , Adolescente , Enfermedades del Desarrollo Óseo/rehabilitación , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Cifosis/etiología , Masculino , Estadificación de Neoplasias , Aparatos Ortopédicos , Dosificación Radioterapéutica , Estudios Retrospectivos , Escoliosis/etiología , Enfermedades de la Columna Vertebral/rehabilitación
17.
J Pediatr Orthop ; 11(3): 284-7, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2056074

RESUMEN

Leg length inequality developed in 12 of 67 children who were treated with radiation therapy to the kidney, abdomen, pelvis, or lower extremities. All these children survived childhood cancer to the age of skeletal maturity. Of the 12 with anisomelia, seven were symptomatic. There were significant relationships between the development of leg length inequality and the total dose of radiation to the pelvic area, asymmetric irradiation to the pelvis, and high-dose irradiation to the leg.


Asunto(s)
Diferencia de Longitud de las Piernas/etiología , Radioterapia/efectos adversos , Abdomen , Adolescente , Niño , Preescolar , Relación Dosis-Respuesta en la Radiación , Femenino , Estudios de Seguimiento , Humanos , Lactante , Pierna/efectos de la radiación , Masculino , Neoplasias/radioterapia
18.
J Nat Prod ; 63(3): 318-21, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10757710

RESUMEN

The Australian sea pen Anthoptilum cf. kukenthali has afforded five new briarane-type diterpenes, anthoptilides A-E. Their structures were determined on the basis of their spectroscopic data. Single-crystal X-ray determination was performed on anthoptilide A. Anthoptilides B and C inhibited the binding of [(3)H]1, 3-dipropyl-8-cyclopentylxanthine ([(3)H]DPCPX) on adenosine A(1) receptors.


Asunto(s)
Cnidarios/química , Diterpenos/aislamiento & purificación , Animales , Diterpenos/química , Estructura Molecular , Análisis Espectral
19.
J Nat Prod ; 59(10): 927-34, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8904842

RESUMEN

Further investigation of the Bismarck Archipelago (Papua New Guinea) marine sponge Ianthella basta for biologically active constituents has led to the isolation of hemibastadins 1 (2), 2 (3), and 3 (4) and the new brominated tyrosine derivatives hemibastadinols 1-3 (9, 13, and 14). Isolation and structure elucidation of the monomethyl ether derivatives (7 and 8) of hemibastadins 1 and 2 and the 3-bromotyramine amide of oxalic acid amide (1a) concluded our chemical investigation of I. basta. The hemibastadins and hemibastadinols represent important biosynthetic links to a series of bromotyrosine tetramers collectively known as the bastadins. The antimicrobial activity of the bastadins, hemibastadins, and hemibastadinols is summarized.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Oximas/aislamiento & purificación , Fenoles/aislamiento & purificación , Poríferos/química , Animales , Antibacterianos , Antiinfecciosos/química , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Cromatografía Liquida , Hongos/efectos de los fármacos , Humanos , Leucemia P388/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Nueva Guinea , Oximas/química , Oximas/farmacología , Fenoles/química , Fenoles/farmacología , Espectrofotometría Ultravioleta
20.
Clin Orthop Relat Res ; (251): 235-40, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2136823

RESUMEN

One hundred forty-three patients who received radiation therapy for childhood tumors, and survived to the age of skeletal maturity, were studied by retrospective review of oncology records and roentgenograms. Diagnoses for the patients were the following: Hodgkin's lymphoma (44), Wilms's tumor (30), acute lymphocytic leukemia (26), non-Hodgkin's lymphoma (18), Ewing's sarcoma (nine), rhabdomyosarcoma (six), neuroblastoma (six), and others (four). Age at the follow-up examination averaged 18 years (range, 14-28 years). Average length of follow-up study was 9.9 years (range, two to 18 years). Asymmetry of the chest and ribs was seen in 51 (36%) of these children. Fifty (35%) had scoliosis; 14 had kyphosis. In two children, the scoliosis was treated with a brace, while one developed significant kyphosing scoliosis after laminectomy and had spinal fusion. Twenty-three (16%) patients complained of significant pain at the radiation sites. Twelve of the patients developed leg-length inequality; eight of those were symptomatic. Three patients developed second primary tumors. Currently, the incidence of significant skeletal sequelae is lower and the manifestations are less severe than reported in the years from 1940 to 1970. The reduction in skeletal complications may be attributed to shielding of growth centers, symmetric field selection, decreased total radiation doses, and sequence changes in chemotherapy.


Asunto(s)
Enfermedades Óseas/etiología , Neoplasias/radioterapia , Traumatismos por Radiación/etiología , Enfermedades de la Columna Vertebral/etiología , Adolescente , Adulto , Dolor de Espalda/etiología , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Diferencia de Longitud de las Piernas/etiología , Masculino , Neoplasias Inducidas por Radiación/etiología , Estudios Retrospectivos , Enfermedades de la Columna Vertebral/terapia , Fusión Vertebral
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