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1.
Ecol Appl ; 30(7): e02140, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32335994

RESUMEN

Automated recognition is increasingly used to extract species detections from audio recordings; however, the time required to manually review each detection can be prohibitive. We developed a flexible protocol called "validation prediction" that uses machine learning to predict whether recognizer detections are true or false positives and can be applied to any recognizer type, ecological application, or analytical approach. Validation prediction uses a predictable relationship between recognizer score and the energy of an acoustic signal but can also incorporate any other ecological or spectral predictors (e.g., time of day, dominant frequency) that will help separate true from false-positive recognizer detections. First, we documented the relationship between recognizer score and the energy of an acoustic signal for two different recognizer algorithm types (hidden Markov models and convolutional neural networks). Next, we demonstrated our protocol using a case study of two species, the Common Nighthawk (Chordeiles minor) and Ovenbird (Seiurus aurocapilla). We reduced the number of detections that required validation by 75.7% and 42.9%, respectively, while retaining at least 98% of the true-positive detections. Validation prediction substantially improves the efficiency of using automated recognition on acoustic data sets. Our method can be of use to wildlife monitoring and research programs and will facilitate using automated recognition to mine bioacoustic data sets.


Asunto(s)
Acústica , Algoritmos , Aprendizaje Automático , Redes Neurales de la Computación
2.
BMC Vet Res ; 10: 167, 2014 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-25080935

RESUMEN

BACKGROUND: Feather pecking and cannibalism are major concerns in poultry farming, both in terms of animal welfare and farm economics. Genetic selection and introduction of (aspects of) maternal care have been suggested as potential interventions to reduce feather pecking in laying hens. Altered brain development has been proposed to reflect welfare states in animals, and can provide more insight into the underlying processes involved in feather pecking. Both vasotocin (the avian homologue of vasopressin) and dopaminergic neural circuitry have roles in control of social behaviors as well as in the stress response, and may be linked to feather pecking. Thus, the hypothalamus of adult laying hens selected for low early mortality (LML), which show low feather pecking, was examined and compared with a control line of adult laying hens selected for production characteristics only (CL). The effect of foster hen rearing on the two genetic lines and their hypothalamic morphology was also investigated. RESULTS: We demonstrated an increase in the number of neurons positive for the rate-limiting enzyme in dopamine production, tyrosine hydroxylase, in the periventricular area of the hypothalamus in the LML hens compared to CL hens. Hen-reared chicks showed more vasotocin -positive neurons in the medial pre-optic area compared to the hens raised without a hen. No correlations were found between behavior in an open field at 5-6 weeks of age, and the histology of the same hens at adulthood. CONCLUSION: The hypothalamic dopaminergic and vasotinergic systems are altered in hens following genetic selection or maternal care, indicating a potential role for these systems in feather pecking.


Asunto(s)
Conducta Animal/fisiología , Pollos/metabolismo , Hipotálamo/metabolismo , Conducta Materna/fisiología , Tirosina 3-Monooxigenasa/metabolismo , Vasotocina/metabolismo , Crianza de Animales Domésticos , Animales , Cruzamiento , Pollos/genética , Femenino , Hipotálamo/citología , Selección Genética
3.
Landsc Ecol ; 39(4): 83, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38550967

RESUMEN

Context: Artificial light at night (ALAN) is increasing worldwide, with many ecological effects. Aerial insectivores may benefit from foraging on insects congregating at light sources. However, ALAN could negatively impact them by increasing nest visibility and predation risk, especially for ground-nesting species like nightjars (Caprimulgidae). Objectives: We tested predictions based on these two alternative hypotheses, potential foraging benefits vs potential predation costs of ALAN, for two nightjar species in British Columbia: Common Nighthawks (Chordeiles minor) and Common Poorwills (Phalaenoptilus nuttallii). Methods: We modeled the relationship between ALAN and relative abundance using count data from the Canadian Nightjar Survey. We distinguished territorial from extra-territorial Common Nighthawks based on their wingboom behaviour. Results: We found limited support for the foraging benefit hypothesis: there was an increase in relative abundance of extra-territorial Common Nighthawks in areas with higher ALAN but only in areas with little to no urban land cover. Common Nighthawks' association with ALAN became negative in areas with 18% or more urban land cover. We found support for the nest predation hypothesis: the were strong negative associations with ALAN for both Common Poorwills and territorial Common Nighthawks. Conclusions: The positive effects of ALAN on foraging nightjars may be limited to species that can forage outside their nesting territory and to non-urban areas, while the negative effects of ALAN on nesting nightjars may persist across species and landscape contexts. Reducing light pollution in breeding habitat may be important for nightjars and other bird species that nest on the ground. Supplementary Information: The online version contains supplementary material available at 10.1007/s10980-024-01875-3.

4.
Animals (Basel) ; 11(3)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33803996

RESUMEN

Many protocols have been developed to assess farm animal welfare. However, the validity of these protocols is still subject to debate. The present study aimed to compare nine welfare assessment protocols, namely: (1) Welfare Quality© (WQ), (2) a modified version of Welfare Quality (WQ Mod), which has a better discriminative power, (3) WelzijnsWijzer (Welfare Indicator; WW), (4) a new Welfare Monitor (WM), (5) Continue Welzijns Monitor (Continuous Welfare Monitor; CWM), (6) KoeKompas (Cow Compass; KK), (7) Cow Comfort Scoring System (CCSS), (8) Stall Standing Index (SSI) and (9) a Welfare Index (WI Tuyttens). In addition, a simple welfare estimation by veterinarians (Estimate vets, EV) was added. Rank correlation coefficients were calculated between each of the welfare assessment protocol scores and mean hair cortisol concentrations from 10 cows at 58 dairy farms spread over the Netherlands. Because it has been suggested that the hair cortisol level is related to stress, experienced over a long period of time, we expected a negative correlation between cortisol and the result of the welfare protocol scores. Only the simple welfare estimation by veterinarians (EV) (ρ = -0.28) had a poor, but significant, negative correlation with hair cortisol. This correlations, however, failed to reach significance after correction of p-values for multiple correlations. Most of the results of the different welfare assessment protocols had a poor, fair or strong positive correlation with each other, supporting the notion that they measure something similar. Additional analyses revealed that the modified Welfare Quality protocol parameters housing (ρ = -0.30), the new Welfare Monitor (WM) parameter health (ρ = -0.33), and milk yield (ρ = -0.33) showed negative correlations with cortisol. We conclude that because only five out of all the parameter scores from the welfare assessment protocols showed a negative, albeit weak, correlation with cortisol, hair cortisol levels may not provide a long term indicator for stress in dairy cattle, or alternatively, that the protocols might not yield valid indices for cow welfare.

5.
Health Qual Life Outcomes ; 8: 85, 2010 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-20716328

RESUMEN

BACKGROUND: The Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire is one of the best-characterized disease-specific instruments that captures health-related problems and symptom-patterns in patients with gastroesophageal reflux disease (GERD). This paper reports the psychometric validation of a Dutch translation of the QOLRAD questionnaire in gastroenterology outpatients with GERD. METHODS: Patients completed the QOLRAD questionnaire at visit 1 (baseline), visit 2 (after 2, 4 or 8 weeks of acute treatment with esomeprazole 40 mg once daily), and visit 4 (after 6 months with on-demand esomeprazole 40 mg once daily or continuous esomeprazole 20 mg once daily). Symptoms were assessed at each visit, and patient satisfaction was assessed at visits 2 and 4. RESULTS: Of the 1166 patients entered in the study, 97.3% had moderate or severe heartburn and 55.5% had moderate or severe regurgitation at baseline. At visit 2, symptoms of heartburn and regurgitation were mild or absent in 96.7% and 97.7%, respectively, and 95.3% of patients reported being satisfied with the treatment. The internal consistency and reliability of the QOLRAD questionnaire (range: 0.83-0.92) supported construct validity. Convergent validity was moderate to low. Known-groups validity was confirmed by a negative correlation between the QOLRAD score and clinician-assessed severity of GERD symptoms. Effect sizes (1.15-1.93) and standardized response means (1.17-1.86) showed good responsiveness to change. GERD symptoms had a negative impact on patients' lives. CONCLUSIONS: The psychometric characteristics of the Dutch translation of the QOLRAD questionnaire were found to be satisfactory, with good reliability and responsiveness to change, although convergent validity was at best moderate.


Asunto(s)
Dispepsia , Reflujo Gastroesofágico , Psicometría , Calidad de Vida , Encuestas y Cuestionarios , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Reproducibilidad de los Resultados , Perfil de Impacto de Enfermedad , Traducciones , Adulto Joven
6.
Dysphagia ; 25(3): 169-76, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19760460

RESUMEN

The aim of this work was to assess the efficacy of external myotomy of the upper esophageal sphincter (UES) for oropharyngeal dysphagia. In the period 1991-2006, 28 patients with longstanding dysphagia and/or aspiration problems of different etiologies underwent UES myotomy as a single surgical treatment. The main symptoms were difficulties in swallowing of a solid-food bolus, aspiration, and recurrent incidents of solid-food blockages. Pre- and postoperative manometry and videofluoroscopy were used to assess deglutition and aspiration. Outcome was defined as success in the case of complete relief or marked improvement of dysphagia and aspiration and as failure in the case of partial improvement or no improvement. Initial results showed success in 21 and failure in 7 patients. The best outcomes were observed in patients with dysphagia of unknown origin, noncancer-related iatrogenic etiology, and neuromuscular disease. No correlation was found between preoperative constrictor pharyngeal muscle activity and success rate. After follow-up of more than 1 year, 20 patients were marked as success and 3 as failure. All successful patients had full oral intake with a normal bolus consistency without clinically significant aspiration. We conclude that in select cases of oropharyngeal dysphagia success may be achieved by UES myotomy with restoration of oral intake of normal bolus consistency.


Asunto(s)
Esfínter Esofágico Superior/cirugía , Reflujo Gastroesofágico/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Intervalos de Confianza , Esfínter Esofágico Superior/patología , Femenino , Fluoroscopía/instrumentación , Fluoroscopía/métodos , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/patología , Humanos , Masculino , Manometría , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Estadística como Asunto , Estadísticas no Paramétricas , Factores de Tiempo , Grabación en Video
7.
Metabolism ; 97: 57-67, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31153978

RESUMEN

BACKGROUND: Muscle atrophy is defined as decreased muscle mass, associated with aging as well as with various chronic diseases and is a fundamental cause of frailty, functional decline and disability. Frailty represents a huge potential public health issue worldwide with high impact on healthcare costs. A major clinical issue is therefore to devise new strategies preventing muscle atrophy. In this study, we tested the efficacy of Vital01, a novel oral nutritional supplement (ONS), on body weight and muscle mass using a caloric restriction-induced mouse model for muscle atrophy. METHODS: Mice were calorically restricted for 2 weeks to induce muscle atrophy: one control group received 60% kcal of the normal chow diet and one intervention group received 30% kcal chow and 30 kcal% Vital01. The effects on body weight, lean body mass, muscle histology and transcriptome were assessed. In addition, the effects of Vital01, in mice with established muscle atrophy, were assessed and compared to a standard ONS. To this end, mice were first calorically restricted on a 60% kcal chow diet and then refed with either 100 kcal% chow, a mix of Vital01 (receiving 60% kcal chow and 40 kcal% Vital01) or with a mix of standard, widely prescribed ONS (receiving 60 kcal% chow and 40 kcal% Fortisip Compact). RESULTS: Vital01 attenuated weight loss (-15% weight loss for Vital01 vs. -25% for control group, p < 0.01) and loss of muscle mass (Vital01 with -13%, -12% and -18%, respectively, for gastrocnemius, quadriceps and tibialis vs. 25%, -23% and -28%, respectively, for control group, all p < 0.05) and also restored body weight, fat and muscle mass more efficiently when compared to Fortisip Compact. As assessed by transcriptome analysis and Western blotting of key proteins (e.g. phospoAKT, mTOR and S6K), Vital01 attenuated the catabolic and anabolic signaling pathways induced by caloric restriction and modulated inflammatory and mitochondrial pathways. In addition, Vital01 affected pathways related to matrix proteins/collagens homeostasis and tended to reduce caloric restriction-induced collagen fiber density in the quadriceps (with -27%, p = 0.051). CONCLUSIONS: We demonstrate that Vital01 preserves muscle mass in a calorically restricted mouse model for muscle atrophy. Vital01 had preventive effects when administered during development of muscle atrophy. Furthermore, when administered in a therapeutic setting to mice with established muscle atrophy, Vital01 rapidly restored body weight and accelerated the recurrence of fat and lean body mass more efficiently than Fortisip Compact. Bioinformatics analysis of gene expression data identified regulatory pathways that were specifically influenced by Vital01 in muscle.


Asunto(s)
Peso Corporal/fisiología , Músculo Esquelético/fisiología , Atrofia Muscular/fisiopatología , Animales , Composición Corporal/fisiología , Índice de Masa Corporal , Restricción Calórica/métodos , Suplementos Dietéticos , Modelos Animales de Enfermedad , Ingestión de Energía/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Pérdida de Peso/fisiología
8.
Curr Biol ; 9(4): 203-6, 1999 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-10074432

RESUMEN

Engagement of the T-cell receptor (TCR)-CD3 complex induces a rapid increase in the activities of Src-family and Syk/Zap-70-family kinases [1] [2]. These activated kinases then induce the tyrosine phosphorylation of multiple intracellular proteins, eventually leading to T-cell activation. One of the prominent substrates for these kinases is the adaptor protein Cbl [3] and recent studies suggest that Cbl negatively regulates upstream kinases such as Syk and Zap-70 [4] [5]. Cbl-b, a homologue of Cbl, is widely expressed in many tissues and cells including hematopoietic cells [6] [7]. Cbl-b undergoes rapid tyrosine phosphorylation upon stimulation of the TCR and cytokine receptors [8] [9]. The role of Cbl-b is unclear, however. Here, we show that overexpression of Cbl-b in T cells induced the constitutive activation of the transcription factor nuclear factor of activated T cells (NFAT). A loss-of-function mutation in Cbl-b disrupted the interaction between Cbl-b and Zap-70 and nearly completely abrogated the Cbl-b-mediated activation of NFAT. Unlike the proposed role of Cbl as a negative regulator, our results suggest that the Cbl homologue Cbl-b has a positive role in T-cell signaling, most likely via a direct interaction with the upstream kinase Zap-70.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas Portadoras/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares , Fosfoproteínas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Complejo Receptor-CD3 del Antígeno de Linfocito T/fisiología , Proteínas Oncogénicas de Retroviridae/metabolismo , Transducción de Señal , Linfocitos T/fisiología , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas , Humanos , Células Jurkat , Cinética , Activación de Linfocitos , Muromonab-CD3/farmacología , Factores de Transcripción NFATC , Proteína Oncogénica v-cbl , Fosforilación , Proteínas Proto-Oncogénicas c-cbl , Receptores de Antígenos de Linfocitos T/fisiología , Proteínas Recombinantes/metabolismo , Linfocitos T/inmunología , Transfección , Proteína Tirosina Quinasa ZAP-70
9.
Mol Cell Biol ; 21(9): 3126-36, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11287617

RESUMEN

Vav, a hematopoiesis-specific signaling protein, plays an important role in T-cell development and activation. Vav upregulates the expression of the interleukin-2 (IL-2) gene, primarily via activation of the distal NFAT site in the IL-2 gene promoter (NFAT-IL-2). However, since this site cooperatively binds NFAT and AP-1, the relative contribution of Vav to NFAT versus AP-1 activation has not been determined. Here, we studied the respective roles of the AP-1 and NFAT pathways in the T-cell receptor (TCR)-mediated, Vav-dependent activation of NFAT-IL-2. Although Vav stimulated the transcriptional activity of an NFAT-IL-2 reporter gene, it failed to stimulate the transcriptional or DNA-binding activities of an AP-1-independent NFAT site derived from the human gamma interferon gene promoter. Vav also did not stimulate detectable Ca(2+) mobilization and nuclear translocation of NFATc or NFATp. On the other hand, Vav induced the activation of Rac1 or Cdc42 and c-Jun N-terminal kinase (JNK), enhanced the transcriptional and DNA-binding activities of AP-1, and induced increased phosphorylation of c-Jun. Dominant-negative Vav and/or Rac1 mutants blocked the TCR-mediated stimulation of these events, demonstrating the physiological relevance of these effects. Vav also associated with Rac1 or Cdc42 in T cells, and anti-CD3 antibody stimulation enhanced this association. These findings indicate that a Rac1-dependent JNK/c-Jun/AP-1 pathway, rather than the Ca(2+)/NFAT pathway, plays the predominant role in NFAT-IL-2 activation by Vav.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas de Unión al ADN/metabolismo , Interleucina-2/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Nucleares , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-jun/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Transducción de Señal/fisiología , Factor de Transcripción AP-1/metabolismo , Factores de Transcripción/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Transporte Activo de Núcleo Celular , Sitios de Unión , Calcio/metabolismo , Núcleo Celular/metabolismo , ADN/metabolismo , Proteínas de Unión al ADN/genética , Activación Enzimática , Factores de Intercambio de Guanina Nucleótido/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos , Células Jurkat , Factores de Transcripción NFATC , Fosforilación , Proteínas Proto-Oncogénicas c-vav , Factor de Transcripción AP-1/genética , Factores de Transcripción/genética , Proteína de Unión al GTP cdc42/metabolismo
10.
Biochim Biophys Acta ; 1741(1-2): 95-102, 2005 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-15955452

RESUMEN

The hallmark of fibrosis is the excessive accumulation of collagen. The deposited collagen contains increased pyridinoline cross-link levels due to an overhydroxylation of lysine residues within the collagen telopeptides. Lysyl hydroxylase 2b (LH2b) is the only lysyl hydroxylase consistently up-regulated in several forms of fibrosis, suggesting that an enhanced LH2b level is responsible for the overhydroxylation of collagen telopeptides. The present paper reports the effect of profibrotic cytokines on the expression of collagen, lysyl hydroxylases and lysyl oxidase in normal human skin fibroblasts, as well as the effect on pyridinoline formation in the deposited matrix. All three isoforms of TGF-beta induce a substantial increase in LH2b mRNA levels, also when expressed relatively to the mRNA levels of collagen type I alpha2 (COL1A2). The TGF-beta isoforms also clearly influence the collagen cross-linking pathway, since higher levels of pyridinoline cross-links were measured. Similar stimulatory effects on LH2b/COL1A2 mRNA expression and pyridinoline formation were observed for IL-4, activin A, and TNF-alpha. An exception was BMP-2, which has no effect on LH2b/COL1A2 mRNA levels nor on pyridinoline formation. Our data show for the first time that two processes, i.e., up-regulation of LH2b mRNA levels and increased formation of pyridinoline cross-links, previously recognized to be inherent to fibrotic processes, are induced by various profibrotic cytokines.


Asunto(s)
Aminoácidos/química , Reactivos de Enlaces Cruzados/farmacología , Citocinas/farmacología , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/metabolismo , Activinas/farmacología , Células Cultivadas , Colágeno Tipo I/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/enzimología , Fibroblastos/metabolismo , Fibrosis/patología , Regulación Enzimológica de la Expresión Génica , Humanos , Subunidades beta de Inhibinas/farmacología , Interleucina-4/farmacología , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/farmacología , ARN Mensajero/metabolismo , Piel/citología , Factores de Tiempo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Regulación hacia Arriba
11.
Eur J Pharmacol ; 539(1-2): 89-98, 2006 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-16687134

RESUMEN

1-{7-[(1-(3,5-Diethoxyphenyl)-3-{[(3,5-difluorophenyl)(ethyl)amino]carbonyl}-4-oxo-1,4-dihydroquinolin-7-yl)oxy]heptyl}-1-methylpiperidinium bromide, R-146224, is a potent, specific ileum apical sodium-dependent bile acid transporter (ASBT) inhibitor; concentrations required for 50% inhibition of [3H]taurocholate uptake in human ASBT-expressing HEK-293 cells and hamster ileum tissues were 0.023 and 0.73 microM, respectively. In bile-fistula rats, biliary and urinary excretion 48 h after 10 mg/kg [14C]R-146224, were 1.49+/-1.75% and 0.14+/-0.05%, respectively, demonstrating extremely low absorption. In hamsters, R-146224 dose-dependently reduced gallbladder bile [3H]taurocholate uptake (ED50: 2.8 mg/kg). In basal diet-fed hamsters, 14-day 30-100 mg/kg R-146224 dose-dependently reduced serum total cholesterol (approximately 40%), high density lipoprotein (HDL) cholesterol (approximately 37%), non-HDL cholesterols (approximately 20%), and phospholipids (approximately 20%), without affecting serum triglycerides, associated with reduced free and esterified liver cholesterol contents. In normocholesterolemic cynomolgus monkeys, R-146224 specifically reduced non-HDL cholesterol. In human ileum specimens, R-146224 dose-dependently inhibited [3H]taurocholate uptake. Potent non-systemic ASBT inhibitor R-146224 decreases bile acid reabsorption by inhibiting the ileal bile acid active transport system, resulting in hypolipidemic activity.


Asunto(s)
Anticolesterolemiantes/farmacología , Ácidos y Sales Biliares/metabolismo , Colesterol/sangre , Transportadores de Anión Orgánico Sodio-Dependiente/antagonistas & inhibidores , Piperidinas/farmacología , Quinolinas/farmacología , Sodio/fisiología , Simportadores/antagonistas & inhibidores , Animales , Anticolesterolemiantes/farmacocinética , Línea Celular , Cricetinae , Humanos , Íleon/efectos de los fármacos , Íleon/metabolismo , Técnicas In Vitro , Macaca fascicularis , Masculino , Proteínas de Transporte de Membrana/biosíntesis , Proteínas de Transporte de Membrana/genética , Mesocricetus , Transportadores de Anión Orgánico Sodio-Dependiente/biosíntesis , Transportadores de Anión Orgánico Sodio-Dependiente/genética , Piperidinas/farmacocinética , Quinolinas/farmacocinética , Ratas , Ratas Sprague-Dawley , Simportadores/biosíntesis , Simportadores/genética , Ácido Taurocólico/antagonistas & inhibidores , Ácido Taurocólico/metabolismo
12.
Anim Reprod Sci ; 92(3-4): 231-40, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16157459

RESUMEN

In the bovine, the concentration of 17beta-estradiol (E2) in the follicular fluid of the dominant follicle is high, indicating a possible role of E2 on the cytoplasmic maturation that occurs before the LH surge. The aim of this study was to investigate the role of E2 on the developmental competence of bovine oocytes originating from different sized follicles and temporarily maintained at the germinal vesicle stage with roscovitine (ROS). First, the efficiency of ROS to inhibit germinal vesicle breakdown (GVBD) in oocytes harvested from small (3-4 mm diameter) and medium (5-8 mm diameter) sized follicles was demonstrated. Next, the effect of E2 during temporary inhibition of GVBD by ROS on the subsequent nuclear maturation was evaluated. Oocytes from small and medium sized follicles were cultured in the presence of ROS, FSH and with or without E2 for 24 h. After this period, oocytes were cultured for another 24 h with FSH but without ROS and E2, after which the nuclear stages and the developmental competence of oocytes were assessed. In conclusion, it is demonstrated that exposure to E2, during temporary inhibition of the GVBD with ROS, affected neither nuclear nor cytoplasmic maturation of oocytes originating from small and medium sized follicles. It might be that in vivo, the increase of E2 during follicle growth is more related to selection of the dominant follicle than to the cytoplamsic maturation of the oocyte as such.


Asunto(s)
Bovinos/fisiología , Estradiol/farmacología , Factor Promotor de Maduración/antagonistas & inhibidores , Oocitos/enzimología , Folículo Ovárico/crecimiento & desarrollo , Animales , Bovinos/embriología , Células Cultivadas , Femenino , Fertilización In Vitro/veterinaria , Hormona Folículo Estimulante/farmacología , Hormona Luteinizante/sangre , Oocitos/crecimiento & desarrollo , Folículo Ovárico/anatomía & histología , Folículo Ovárico/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Purinas/farmacología , Roscovitina
13.
Clin Cancer Res ; 22(12): 3025-36, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27306793

RESUMEN

PURPOSE: The purpose of this study was to assess the effect of neoadjuvant chemotherapy (NACT) on immune activation in stage IIIC/IV tubo-ovarian high-grade serous carcinoma (HGSC), and its relationship to treatment response. EXPERIMENTAL DESIGN: We obtained pre- and posttreatment omental biopsies and blood samples from a total of 54 patients undergoing platinum-based NACT and 6 patients undergoing primary debulking surgery. We measured T-cell density and phenotype, immune activation, and markers of cancer-related inflammation using IHC, flow cytometry, electrochemiluminescence assays, and RNA sequencing and related our findings to the histopathologic treatment response. RESULTS: There was evidence of T-cell activation in omental biopsies after NACT: CD4(+) T cells showed enhanced IFNγ production and antitumor Th1 gene signatures were increased. T-cell activation was more pronounced with good response to NACT. The CD8(+) T-cell and CD45RO(+) memory cell density in the tumor microenvironment was unchanged after NACT but biopsies showing a good therapeutic response had significantly fewer FoxP3(+) T regulatory (Treg) cells. This finding was supported by a reduction in a Treg cell gene signature in post- versus pre-NACT samples that was more pronounced in good responders. Plasma levels of proinflammatory cytokines decreased in all patients after NACT. However, a high proportion of T cells in biopsies expressed immune checkpoint molecules PD-1 and CTLA4, and PD-L1 levels were significantly increased after NACT. CONCLUSIONS: NACT may enhance host immune response but this effect is tempered by high/increased levels of PD-1, CTLA4, and PD-L1. Sequential chemoimmunotherapy may improve disease control in advanced HGSC. Clin Cancer Res; 22(12); 3025-36. ©2016 AACR.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Terapia Neoadyuvante/métodos , Neoplasias Ováricas/patología , Linfocitos T Reguladores/inmunología , Microambiente Tumoral/inmunología , Adulto , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/inmunología , Biomarcadores de Tumor/metabolismo , Antígeno CTLA-4/metabolismo , Citocinas/sangre , Procedimientos Quirúrgicos de Citorreducción , Femenino , Humanos , Inmunoterapia/métodos , Activación de Linfocitos/inmunología , Recuento de Linfocitos , Persona de Mediana Edad , Neoplasias Ováricas/terapia , Receptor de Muerte Celular Programada 1/metabolismo
14.
Oncogene ; 18(5): 1147-56, 1999 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-10022120

RESUMEN

Cbl-b, a mammalian homolog of Cbl, consists of an N-terminal region (Cbl-b-N) highly homologous to oncogenic v-Cbl, a Ring finger, and a C-terminal region containing multiple proline-rich stretches and potential tyrosine phosphorylation sites. In the present study, we demonstrate that upon engagement of the T cell receptor (TCR), endogenous Cbl-b becomes rapidly tyrosine-phosphorylated. In heterogeneous COS-1 cells, Cbl-b was phosphorylated on tyrosine residues by both Syk- (Syk/Zap-70) and Src- (Fyn/Lck) family kinases, with Syk kinase inducing the most prominent effect. Syk associates and phosphorylates Cbl-b in Jurkat T cells. A Tyr-316 Cbl-binding site in Syk was required for the association with and for the maximal tyrosine phosphorylation of Cbl-b. Mutation at a loss-of-function site (Gly-298) in Cbl-b-N disrupts its interaction with Syk. Cbl-b constitutively binds Grb2 and becomes associated with Crk-L upon TCR stimulation. The Grb2- and the Crk-L-binding regions were mapped to the C-terminus of Cbl-b. The Crk-L-binding sites were further determined to be Y655DVP and Y709KIP, with the latter being the primary binding site. Taken together, these results implicate that Cbl-b is involved in TCR-mediated intracellular signaling pathways.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Complejo CD3/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/metabolismo , Ubiquitina-Proteína Ligasas , Sitios de Unión , Humanos , Células Jurkat , Activación de Linfocitos , Proteínas Nucleares/metabolismo , Fosforilación , Prolina , Unión Proteica , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-cbl , Transducción de Señal , Tirosina , Proteína Tirosina Quinasa ZAP-70 , Familia-src Quinasas/metabolismo
15.
Eur J Gastroenterol Hepatol ; 17(11): 1213-24, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16215434

RESUMEN

This review focuses on immunogenetic aspects of diseases of the upper gastrointestinal tract in which infectious agents may play a role in the aetiopathogenesis, such as Helicobacter pylori, Epstein-Barr virus (EBV) and HIV. Gastric adenocarcinoma is a common cancer all around the world, with declining incidences in Europe and high incidences in Asia and central and south America. Together with gastric atrophy and peptic ulcer disease, gastric adenocarcinoma belongs to the commonest upper gastrointestinal tract diseases. These diseases are multifactorial and factors such as smoking and dietary habits contribute to the pathogenesis. More recently, scientists have turned their eyes on the host. Functional polymorphisms in the genes regulating the host immune system may contribute to the susceptibility to and progression of disease. In multifactorial and polygenetic diseases, candidate gene studies of single nucleotide polymorphisms (SNPs) detect small to moderate relative risks. Unfortunately, only a few functional SNPs have been identified. The candidate gene approach can be seen as a useful first step in exploring causal pathways between genetic determinants and complex diseases such as those mentioned above. To date, little is known about the immunogenetics of upper gastrointestinal tract diseases. We review the literature on H. pylori, EBV and gene polymorphisms that affect key immune mediators influencing the pathogenesis of the inflammatory response, such as the genes that code for the IL-1 family, TNF-alpha, lymphotoxin alpha, and IL-10. IL-1, IL-10, lymphotoxin alpha and TNF-alpha polymorphisms increase the risk of upper gastrointestinal pathogenesis in H. pylori-infected patients, whereas IL-1 and TNF-alpha polymorphisms confer risk in EBV-infected patients.


Asunto(s)
Citocinas/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Enfermedades Gastrointestinales/microbiología , Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Infecciones por Virus de Epstein-Barr/genética , Enfermedades Gastrointestinales/genética , Predisposición Genética a la Enfermedad/genética , Infecciones por Helicobacter/genética , Humanos , Inmunogenética , Interleucina-1/genética , Polimorfismo Genético
16.
Reprod Fertil Dev ; 17(8): 775-84, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16476204

RESUMEN

Bovine blastocysts produced in vitro differ substantially from their in vivo-derived counterparts with regard to glucose metabolism, level of apoptosis and mRNA expression patterns. Maternal embryonic genomic transition is a critical period in which these changes could be induced. The goals of the present study were twofold: (1) to identify the critical period of culture during which the differences in expression of gene transcripts involved in glucose metabolism are induced; and (2) to identify gene transcripts involved in apoptosis that are differentially expressed in in vitro- and in vivo-produced blastocysts. Relative abundances of transcripts for the glucose transporters Glut-1, Glut-3, Glut-4 and Glut-8, and transcripts involved in the apoptotic cascade, including BAX, BCL-XL, XIAP and HSP 70.1, were analysed by a semiquantitative reverse transcription-polymerase chain reaction assay in single blastocysts produced in vitro or in vivo for specific time intervals, that is, before or after maternal embryonic transition. Whether the culture environment was in vitro or in vivo affected the expression of glucose transporter transcripts Glut-3, Glut-4 and Glut-8. However, the critical period during culture responsible for these changes, before or after maternal embryonic transition, could not be determined. With the exception of XIAP, no effects of culture system on the mRNA expression patterns of BAX, BCL-XL and HSP 70.1 could be observed. These data show that expression of XIAP transcripts in expanded blastocysts is affected by in vitro culture. These findings add to the list of bovine genes aberrantly expressed in culture conditions, but do not support the hypothesis that maternal embryonic transition is critical in inducing the aberrations in gene expression patterns studied here.


Asunto(s)
Apoptosis/genética , Técnicas de Cultivo de Embriones/veterinaria , Embrión de Mamíferos/metabolismo , Expresión Génica , Metabolismo/genética , ARN Mensajero/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Bovinos , Cartilla de ADN , Técnicas de Cultivo de Embriones/métodos , Glucosa/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria
17.
Disabil Rehabil ; 27(22): 1381-9, 2005 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-16321920

RESUMEN

PURPOSE: To investigate the prevalence of health problems among persons with spinal cord injury (SCI) living in the Netherlands, to identify the problems experienced as most important, and to analyse the experienced impact of these most important problems on daily activities and social life. METHOD: Postal survey among all members of the Dutch Association of Patients with SCI. The questionnaire focused on 26 health problems: 13 secondary impairments, 8 problems of daily living and 5 psychosocial problems. RESULTS: The respondents (response rate 45.5%, 454 persons) experienced an average of 8 health problems. The most frequently occurring problems regarded bladder and bowel regulation, spasms, pain, oedema and sexuality. Except for oedema, these problems were also most often cited as the most important. The most disabling condition for both daily and social activities was pain. Few significant relationships were found between the prevalence of health problems and the level, completeness and duration of the injury or gender. CONCLUSION: Persons with SCI living in the community experience many health problems and limitations in daily activities and social life due to these problems. The occurrence of these problems does not diminish with increasing time after injury. This strongly emphasises the need for follow-up care.


Asunto(s)
Indicadores de Salud , Calidad de Vida , Traumatismos de la Médula Espinal/complicaciones , Actividades Cotidianas , Adulto , Femenino , Encuestas Epidemiológicas , Humanos , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Países Bajos , Prevalencia , Traumatismos de la Médula Espinal/psicología , Encuestas y Cuestionarios
18.
Biochem Pharmacol ; 63(9): 1755-61, 2002 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-12007578

RESUMEN

Previous rodent studies suggested that the potent hypolipidemic agent 4-amino-2-(4,4-dimethyl-2-oxo-1-imidazolidinyl)pyrimidine-5-N-(trifluoromethyl-phenyl) carboxamide monohydrochloride (HOE 402) is an inducer of the LDL receptor (LDLR). Using wild-type and heterozygous and homozygous LDLR-deficient (LDLR+/0 and LDLR0/0) mice, fed a low or high cholesterol diet, we investigated whether HOE 402 specifically induces the LDLR and whether other pathways are affected. Upon treatment with 0.05% (w/w) HOE 402, the serum cholesterol levels of wild-type, LDLR+/0 and LDLR0/0 mice, were maximally reduced by 53, 56, and 73%, respectively (P<0.05), by reducing levels in very low density-lipoprotein (VLDL), intermediate density-lipoprotein (IDL), and low density-lipoprotein (LDL) cholesterol, whereas high density-lipoprotein (HDL) cholesterol levels were increased. The observations that HOE 402 exhibited no effect on in vivo clearance of 125I-labeled LDL in wild-type mice, and clearly reduced serum cholesterol levels in LDLR0/0 mice, indicate that the LDLR is not the main target for the compound. In wild-type mice, production of VLDL-TG, and cholesterol were reduced by more than 50% by HOE 402 (P<0.05), whereas VLDL apolipoprotein B (ApoB) secretion was unaffected, indicating that HOE 402 treatment changes the size, rather than the number of the secreted VLDL particles. The reduced VLDL production was accompanied by a 22% decreased hepatic cholesterol ester concentration (P<0.05). Additionally, HOE 402 treatment strongly reduced the aortic content of atherosclerotic lesions by 90 and 72% in LDLR+/0 and LDLR0/0 mice, respectively (P<0.01). In conclusion, HOE 402 is a potent cholesterol-lowering compound, which inhibits VLDL production, and consequently attenuates atherosclerosis development.


Asunto(s)
Arteriosclerosis/prevención & control , Colesterol/sangre , Hipolipemiantes/uso terapéutico , Imidazoles/uso terapéutico , Lipoproteínas VLDL/metabolismo , Pirimidinas/uso terapéutico , Receptores de LDL/metabolismo , Animales , Aorta/patología , Modelos Animales de Enfermedad , Lípidos/sangre , Ratones , Ratones Noqueados , Receptores de LDL/genética
20.
J Cardiovasc Pharmacol ; 45(1): 53-60, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15613980

RESUMEN

The present study was designed to investigate the lipid-lowering properties and mechanisms of action of a new HMG-CoA reductase inhibitor, rosuvastatin, in female ApoE*3-Leiden transgenic mice. Mice received a high fat/cholesterol (HFC) diet containing either rosuvastatin (0 [control], 0.00125%, 0.0025%, or 0.005% [w/w]) or 0.05% (w/w) lovastatin. The highest dose of rosuvastatin reduced plasma cholesterol and triglyceride levels by 39% and 42%, respectively, compared with the HFC control. Lovastatin had no effect on plasma cholesterol and triglyceride levels. In ApoE*3-Leiden mice on a chow diet, rosuvastatin (0.005% [w/w]) decreased plasma cholesterol levels by 35% without having an effect on triglyceride levels. On a chow diet, expression of genes involved in cholesterol biosynthesis and uptake in the liver was increased by rosuvastatin. Further mechanistic studies in HFC-fed mice showed that rosuvastatin treatment resulted in decreased hepatic VLDL-triglyceride and VLDL-apolipoprotein B production. VLDL lipid composition remained unchanged, indicating a reduction in the number of VLDL particles secreted. Lipolytic activity and expression of genes involved in cholesterol and triglyceride synthesis and beta-oxidation of fatty acids in the liver were not affected by rosuvastatin treatment, and hepatic lipid content did not change. However, activity of hepatic diacylglycerol acyltransferase was significantly decreased by 25% after rosuvastatin treatment. Moreover, biliary excretion of cholesterol, phospholipids, and bile acids was increased during treatment. The results indicate that rosuvastatin treatment in ApoE*3-Leiden mice on a HFC diet leads to redistribution of cholesterol and triglycerides in the body, both by reduced hepatic VLDL production and triglyceride synthesis and by enhanced hepatobiliary removal of cholesterol, bile acids, and phospholipids, resulting in substantial reductions in plasma cholesterol and triglyceride levels.


Asunto(s)
Apolipoproteínas E/genética , VLDL-Colesterol/biosíntesis , Colesterol/metabolismo , Fluorobencenos/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Pirimidinas/farmacología , Sulfonamidas/farmacología , Triglicéridos/metabolismo , Animales , Apolipoproteína E3 , Apolipoproteínas B/biosíntesis , Bilis/metabolismo , Ácidos y Sales Biliares/metabolismo , Colesterol/sangre , Colesterol/genética , VLDL-Colesterol/sangre , Cromatografía Líquida de Alta Presión , Heces/química , Femenino , Hígado/metabolismo , Ratones , Ratones Transgénicos , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rosuvastatina Cálcica , Esteroles/metabolismo , Triglicéridos/sangre , Triglicéridos/genética
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