Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 166
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Tech Coloproctol ; 19(4): 209-19, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25577276

RESUMEN

BACKGROUND: Laparoscopic ventral mesh rectopexy (LVR) is gaining wider acceptance as the preferred procedure to correct internal as well as external rectal prolapse associated with obstructed defaecation syndrome and/or faecal incontinence. Very few reports exist on the use of biologic mesh for LVR. The aim of our study was to report the complication and recurrence rate of our first 100 cases of LVR for symptomatic internal rectal prolapse and/or rectocele using a porcine dermal collagen mesh. METHODS: Prospectively collected data on LVR for internal rectal prolapse were analysed. Surgical complications and functional results in terms of faecal incontinence (measured with the Faecal Incontinence Severity Index = FISI) and constipation (measured with the Wexner Constipation Score = WCS) at 3, 6 and 12 months were analysed. It was considered an improvement if FISI or WCS scores were reduced by at least 25 % and a cure if the FISI score decreased to <10 and the WCS decreased to <5. RESULTS: Between April 2009 and April 2013, 100 consecutive female patients (mean age 63 years, range 24-88 years) underwent LVR. All patients had internal rectal prolapse (grade III [n = 25] and grade IV [n = 75] according to the Oxford classification) and rectocele. Mean operative time was 85 ± 40 min. Conversion rate to open technique was 1 %. There was no post-operative mortality. Overall 16 patients (16 %) experienced 18 complications, including rectal perforation (n = 1), small bowel obstruction (n = 2), urinary tract infection (n = 8), subcutaneous emphysema (n = 3), wound haematoma (n = 2), long lasting sacral pain (n = 1) and incisional hernia (1). Median post-operative length of stay was 2 days. Ninety-eight out of 100 patients completed follow-up. At the end of follow-up, the mean FISI score improved from 8.4 (±4.0 standard deviation (SD) p = 0.003) to 3.3 ± 2.3 SD (p = 0.04). Incontinence improved in 37 out of 43 patients (86 %), and 31 patients (72 %) were cured. Similarly, the mean WCS score improved from 18.4 ± 11.6 SD to 5.4 ± 4.1 SD (p = 0.04). Constipation improved in 82 out of 89 patients (92 %), and 70 patients (79 %) were cured. No worsening of continence status, constipation or sexual function was observed. Fourteen patients (14 %) experienced persistence or recurrence of prolapse. CONCLUSIONS: LVR using biologic mesh is a safe and effective procedure for improving symptoms of obstructed defaecation and faecal incontinence in patients with internal rectal prolapse associated with rectocele.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Incontinencia Fecal/cirugía , Laparoscopía/efectos adversos , Prolapso Rectal/cirugía , Mallas Quirúrgicas/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Canal Anal/fisiopatología , Canal Anal/cirugía , Estreñimiento/etiología , Estreñimiento/cirugía , Defecación , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Incontinencia Fecal/etiología , Femenino , Estudios de Seguimiento , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Laparoscopía/métodos , Tiempo de Internación , Persona de Mediana Edad , Tempo Operativo , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Prolapso Rectal/complicaciones , Rectocele/complicaciones , Rectocele/cirugía , Recto/fisiopatología , Recto/cirugía , Recurrencia , Resultado del Tratamiento
2.
Opt Lett ; 37(17): 3543-5, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22940943

RESUMEN

We demonstrate a self-starting Kerr-lens mode-locked (KLM) Yb:YAG thin-disk oscillator operating in the regime of positive intracavity group-delay dispersion (GDD). It delivers 1.7 ps pulses at an average power of 17 W and a repetition rate of 40 MHz. Dispersive mirrors compress the pulses to a duration of 190 fs (assuming sech2 shape; Fourier limit: 150 fs) at an average power level of 11 W. To our knowledge, this is the first KLM thin-disk oscillator with positive GDD. Output powers of up to 30 W were achieved with an increased output coupler transmission and intracavity GDD. We demonstrate increase of the pulse energy with increasing positive intracavity GDD, limited by difficulties in initiating mode-locking.

3.
J Biol Regul Homeost Agents ; 26(3 Suppl): 49-59, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23158515

RESUMEN

BACKGROUND: A mixture of neutral prebiotic oligosaccharides has been shown to reduce the incidence of atopic dermatitis (AD) and allergy associated symptoms during the first 2 years of life. OBJECTIVE: To evaluate if this protective effect against allergy lasted beyond the intervention period until 5 y of age. METHODS: In a prospective, double blind, placebo-controlled fashion, healthy term infants at risk of atopy were fed either a prebiotic-supplemented (0.8 g/100 ml scGOS/lcFOS) or placebo-supplemented (0.8 g/100 ml maltodextrin) hypoallergenic formula during the first 6 mo of life. Following this intervention period, follow-up continued until 5 y of life. The present study evaluated (i) the cumulative incidence of allergic manifestations during 5 y, and (ii) the prevalence of allergic and persistent allergic manifestations at 5 y. Monitored allergic manifestations were AD, recurrent wheezing, allergic rhinoconjunctivitis and urticaria. RESULTS: Ninety-two children (50 in placebo group, 42 in intervention group) completed the 5-y follow-up. The 5-y cumulative incidences of any allergic manifestation and atopic dermatitis were significantly lower in the scGOS/lcFOS group (30.9, 19.1 %, respectively) compared to placebo group (66, 38 %, respectively) (p< 0.01 and< 0.05). Children in the scGOS/lcFOS group tended to have a lower incidence of allergic rhinoconjunctivitis, and allergic urticaria (4.8 vs 16% for both manifestations, p=0.08). There was no difference in the cumulative incidence of recurrent wheezing. With regard to the prevalences at 5 y, intervention group had significantly lower prevalence of any persistent allergic manifestation and rhinoconjunctivitis (4.8, 2.4 %, respectively) compared to placebo (26, 14 %, respectively) (p < 0.01 and =0.05). Prevalence of persistent AD tended to be lower in the intervention group (2.4 vs 12%, p= 0.09). Although intervention group had 75% reduction in the prevalence of persistent wheezing (4.8 vs 14 %), no significance was shown. CONCLUSION: Oligosaccharide prebiotics (scGOS/lcFOS), when started early in life have a protective effect against allergic manifestations in high risk infants. The protection lasts beyond infancy until 5 y of life, for AD and allergic rhinoconjunctivitis. Long-term follow-up studies in larger populations are warranted to evaluate the potential preventive effect of this mixture on asthma.


Asunto(s)
Asma/prevención & control , Conjuntivitis Alérgica/prevención & control , Dermatitis Atópica/prevención & control , Suplementos Dietéticos , Oligosacáridos/administración & dosificación , Prebióticos , Urticaria/prevención & control , Asma/dietoterapia , Preescolar , Conjuntivitis Alérgica/dietoterapia , Dermatitis Atópica/dietoterapia , Método Doble Ciego , Femenino , Humanos , Incidencia , Lactante , Masculino , Placebos , Polisacáridos/administración & dosificación , Estudios Prospectivos , Ruidos Respiratorios/efectos de los fármacos , Factores de Tiempo , Urticaria/dietoterapia
4.
Colorectal Dis ; 14 Suppl 3: 24-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23136821

RESUMEN

Several biomaterials have been proposed to treat anal fistula alone or in combination with other surgical procedures aiming to reduce recurrence rates while minimizing continence impairment. More recently a porcine dermal matrix injection has been proposed as infill biomaterial to treat fistulae. We propose an approach consisting of non-cutting seton positioning followed several weeks later by flap repair associated with dermal matrix injection into the fistula tracts. We report our experience with this two-staged procedure on 24 consecutive patients with complex anal fistulae with a median follow up of > 12 months. In our experience this two-stage approach seems to be safe and effective.


Asunto(s)
Colágeno/administración & dosificación , Fístula Rectal/cirugía , Colgajos Quirúrgicos , Adulto , Anciano , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Inyecciones , Persona de Mediana Edad , Dimensión del Dolor , Complicaciones Posoperatorias , Recurrencia , Resultado del Tratamiento , Adulto Joven
5.
Opt Lett ; 36(24): 4746-8, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22179870

RESUMEN

We demonstrate a power-scalable Kerr-lens mode-locked Yb:YAG thin-disk oscillator. It delivers 200 fs pulses at an average power of 17 W and a repetition rate of 40 MHz. At an increased (180 W) pump power level, the laser produces 270 fs 1.1 µJ pulses at an average power of 45 W (optical-to-optical efficiency of 25%). Semiconductor-saturable-absorber-mirror-assisted Kerr-lens mode locking (KLM) and pure KLM with a hard aperture show similar performance. To our knowledge, these are the shortest pulses achieved from a mode-locked Yb:YAG disk oscillator and this is the first demonstration of a Kerr-lens mode-locked thin-disk laser.

6.
Acta Paediatr ; 100(11): 1426-31, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21449921

RESUMEN

AIM: To determine the effect of neutral oligosaccharides [small-chain galacto-oligosaccharides/long-chain fructo-oligosaccharides (scGOS/lcFOS)] in combination with acidic oligosaccharides (pAOS) on stool viscosity, stool frequency and stool pH in preterm infants. METHODS: In this explorative RCT, preterm infants with gestational age <32 weeks and/or birth weight <1500 g received enteral supplementation with scGOS/lcFOS/pAOS or placebo (maltodextrin) between days 3 and 30 of life. Stool samples were collected at day 30 after birth. RESULTS: In total, 113 infants were included. Baseline and nutritional characteristics were not different between both groups. Stool viscosity at day 30 was lower in the prebiotics group (16.8N) (3.9-67.8) compared with the placebo group (26.3N) (1.3-148.0) (p = 0.03; 95% CI -0.80 to 0.03). There was a trend towards higher stool frequency in the prebiotics group (3.1 ± 0.8) compared with the placebo group (2.8 ± 0.7) (p = 0.15; 95% CI -0.08 to 0.52). Stool pH at day 30 was lower in the in the prebiotics group (5.9 ± 0.6) compared with the placebo group (6.2 ± 0.3) (p = 0.009; 95% CI 0.08 to 0.53). CONCLUSIONS: Enteral supplementation of a prebiotic mixture consisting of neutral (scGOS/lcFOS) and acidic oligosaccharides (pAOS) decreases stool viscosity and stool pH with a trend towards increased stool frequency in preterm infants. The inclusion of pAOS in a formula containing a mixture of scGOS/lcFOS does not add specific advantages to the formula in terms of stool viscosity, frequency, pH as well as feeding tolerance.


Asunto(s)
Heces/química , Tránsito Gastrointestinal/fisiología , Oligosacáridos/uso terapéutico , Defecación/fisiología , Nutrición Enteral , Humanos , Concentración de Iones de Hidrógeno , Fórmulas Infantiles/química , Fórmulas Infantiles/normas , Recién Nacido , Recien Nacido Prematuro/fisiología , Recién Nacido de muy Bajo Peso/fisiología , Unidades de Cuidado Intensivo Neonatal , Leche Humana/química , Países Bajos , Oligosacáridos/administración & dosificación , Oligosacáridos/fisiología , Prebióticos , Viscosidad
7.
Pediatr Allergy Immunol ; 21(2 Pt 2): e377-85, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20003064

RESUMEN

This double-blind, randomized, placebo-controlled study, aimed to explore the effect of an infant milk formula (IMF) with 6 g/l short-chain galacto- and long-chain fructo-oligosaccharides (scGOS/lcFOS, ratio 9:1) on basal immune parameters in 215 healthy, term infants during the first 26 wk of life. After birth, the infants received breast milk or were randomized to receive an IMF with or without scGOS/lcFOS. Blood samples were collected at the age of 8 wk and 26 wk for the analysis of serum immunoglobulins, lymphocyte subpopulations, and cytokines. The scGOS/lcFOS group and the control group were compared in the statistical analysis. A breast fed group was included as a reference. In total, 187 Infants completed the study. No significant differences were observed between both formula groups in the different studied immune parameters at weeks 8 and 26. This explorative study indicates that supplementation of infant formula with a mixture of prebiotic oligosaccharides did not change the basal level of the measured parameters of the developing immune system in healthy infants with a balanced immune system during the first 6 months of life in comparison to feeding a standard infant formula and in comparison to exclusive breastfeeding.


Asunto(s)
Sistema Inmunológico/inmunología , Fórmulas Infantiles/administración & dosificación , Oligosacáridos , Prebióticos , Animales , Lactancia Materna , Citocinas/metabolismo , Método Doble Ciego , Femenino , Humanos , Inmunoglobulinas/sangre , Fórmulas Infantiles/química , Fenómenos Fisiológicos Nutricionales del Lactante , Bienestar del Lactante , Recién Nacido , Subgrupos Linfocitarios/inmunología , Leche , Leche Humana/inmunología , Oligosacáridos/administración & dosificación , Oligosacáridos/inmunología , Embarazo , Tercer Trimestre del Embarazo , Resultado del Tratamiento
8.
Behav Brain Res ; 379: 112366, 2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-31743728

RESUMEN

Research has demonstrated that stress can exacerbate AD pathology in transgenic mouse models of AD. The purpose of the present studies was to extend this work by determining whether a social stressor, isolation stress, would increase the number of Aß plaques in 5xFAD + transgenic mice in comparison to group-housed controls, and accelerate the onset of cognitive deficits in contextual fear-conditioning. Additionally, we aimed to determine whether the pathological impact of isolation stress could be prevented through exposure to exercise alone or to exercise and an enriched environment throughout the isolation period. Two-month-old 5xFAD + and 5xFAD- animals were isolated or group-housed for two and three months. An additional subset of 5xFAD + mice were housed in isolation, housed in isolation with an exercise wheel, or housed in isolation with an exercise wheel and an enriched environment. Both two and three months of isolation stress significantly increased the number of plaques in the hippocampus of 5xFAD + mice, and three months of isolation increased hippocampal BACE1 expression. Isolated animals also displayed a significant cognitive deficit in contextual fear-conditioning, independent of genotype. Furthermore, neither exercise nor an enriched environment were able to prevent these isolation-induced effects. Understanding how stress impacts the onset and progression of AD is critical, as many individuals endure significant stress over their lifespan, including prolonged social isolation, a societal trend likely to worsen with time.


Asunto(s)
Enfermedad de Alzheimer , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/metabolismo , Disfunción Cognitiva , Hipocampo/metabolismo , Condicionamiento Físico Animal/fisiología , Placa Amiloide/metabolismo , Aislamiento Social , Estrés Psicológico , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/prevención & control , Péptidos beta-Amiloides/metabolismo , Animales , Disfunción Cognitiva/etiología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/prevención & control , Modelos Animales de Enfermedad , Ambiente , Vivienda para Animales , Masculino , Ratones , Ratones Transgénicos , Carrera/fisiología , Estrés Psicológico/complicaciones , Estrés Psicológico/metabolismo , Estrés Psicológico/prevención & control
9.
Behav Brain Res ; 378: 112303, 2020 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-31622640

RESUMEN

Although one of the defining characteristics of Alzheimer's disease is the presence of amyloid-beta (Aß) plaques, the early accumulation of soluble Aß oligomers (AßOs) may disrupt synaptic function and trigger cognitive impairments long before the appearance of plaques. Furthermore, murine models aimed at understanding how AßOs alter formation and retrieval of associative memories are conducted using human Aß species, which are more neurotoxic in the mouse brain than the native murine species. Unfortunately, there is currently a lack of attention in the literature as to what the murine version of the peptide (mAß) does to synaptic function and how it impacts the consolidation and retrieval of associative memories. In the current study, adult mice were infused with mAß 0, 2, 6, or 46 h after contextual-fear conditioning, and were tested 2-48 h later. Interestingly, only mAß infusions within 2 h of training reduced freezing behavior at test, indicating that mAß disrupted the consolidation, but not retrieval of fear memory. This consolidation deficit coincided with increased IL-1ß and reduced synaptophysin mRNA levels, without disrupting other synaptic signaling-related genes here examined. Despite differences between murine and human Aß, the deleterious functional outcomes of early-stage synaptic oligomer presence are similar. Thus, models utilizing or inducing the production of mAß in non-transgenic animals are useful in exploring the role of dysregulated synaptic plasticity and resultant learning deficits induced by Aß oligomers.


Asunto(s)
Péptidos beta-Amiloides/farmacología , Conducta Animal/efectos de los fármacos , Condicionamiento Clásico/efectos de los fármacos , Miedo/efectos de los fármacos , Hipocampo/efectos de los fármacos , Inflamación/inducido químicamente , Consolidación de la Memoria/efectos de los fármacos , Recuerdo Mental/efectos de los fármacos , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/administración & dosificación , Animales , Modelos Animales de Enfermedad , Hipocampo/inmunología , Hipocampo/metabolismo , Inflamación/inmunología , Inflamación/metabolismo , Infusiones Intraventriculares , Masculino , Ratones , Ratones Endogámicos C57BL
10.
Allergy ; 64(3): 484-7, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18507650

RESUMEN

BACKGROUND: It has been suggested that human breast milk oligosaccharides play a role in the development of the immune system in infants, and may consequently inhibit the onset of allergy. A specific prebiotic mixture of short-chain galacto-oligosaccharides and long-chain fructo-oligosaccharides (GOS/FOS) has been shown to reduce the incidence of atopic dermatitis (AD) at 6 months of age in infants at risk for allergy. AIM OF THE STUDY: This study was aimed to analyze the effect of GOS/FOS on the immune response in these infants. METHODS: In a double-blind randomized placebo-controlled study, infants received a hypoallergenic whey formula with either 8 g/l GOS/FOS in a 9 : 1 ratio (IMMUNOFORTIS) or 8 g/l maltodextrine (placebo) for 6 months. At 3 months of age, children were vaccinated with Hexavac against a.o. diphteria, tetanus, polio (DTP). At 6 months of age, plasma samples were collected from 84 infants (verum group n = 41, placebo group n = 43). Levels of total immunoglobulins (Ig) and of cow's milk protein (CMP-) and DTP-specific Ig were measured. RESULTS: GOS/FOS supplementation led to a significant reduction in the plasma level of total IgE, IgG1, IgG2 and IgG3, whereas no effect on IgG4 was observed. CMP-specific IgG1 was significantly decreased. DTP-specific Ig levels were not affected. CONCLUSIONS: This study shows that GOS/FOS supplementation induces a beneficial antibody profile. GOS/FOS reduces the total Ig response and modulates the immune response towards CMP, while leaving the response to vaccination intact. This suggests that oral GOS/FOS supplementation is a safe method to restrain the atopic march.


Asunto(s)
Dermatitis Atópica/prevención & control , Fórmulas Infantiles/química , Oligosacáridos/uso terapéutico , Alérgenos/inmunología , Animales , Dermatitis Atópica/inmunología , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Humanos , Hipersensibilidad/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Lactante , Leche/inmunología , Leche Humana/química , Oligosacáridos/inmunología , Factores de Riesgo
11.
Behav Brain Res ; 359: 871-877, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30031883

RESUMEN

Alzheimer's disease is marked by the presence of amyloid-beta (Aß) plaques, elevated central cytokine levels, dysregulation of BDNF-related gene expression, and cognitive decline. Previously, our laboratory has demonstrated that repeated administration of peripheral LPS is sufficient to significantly increase the presence of central Aß in the hippocampus, and that this upregulation corresponds with deficits in learning and memory. We have also previously demonstrated that the inverse benzodiazepine agonist MRK-016 (MRK) can protect against memory acquisition and consolidation errors in mice. To extend these findings, the current study explored the protective effects of MRK in the context of LPS-induced hippocampal Aß accumulation. Hippocampal Aß was significantly elevated, relative to saline-treated animals, following seven days of peripheral LPS injections. Animals were then trained in a contextual fear conditioning paradigm and were immediately treated with MRK or saline once training was complete. Behavioral testing occurred the day after training. Results from this study demonstrate that repeated injections of LPS significantly elevate hippocampal Aß, and inhibit acquisition of contextual fear. Post-training treatment with MRK restored behavioral expression of fear in LPS-treated animals, despite elevated hippocampal Aß, an effect that may be attributed to increased BDNF mRNA expression. Therefore, our data indicate that MRK can prevent LPS- induced cognitive deficits associated with elevated Aß, and restore hippocampal BDNF expression.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Trastornos del Conocimiento/prevención & control , Agonistas del GABA/uso terapéutico , Hipocampo/metabolismo , Isoxazoles/uso terapéutico , Triazinas/uso terapéutico , Péptidos beta-Amiloides/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/genética , Trastornos del Conocimiento/inducido químicamente , Trastornos del Conocimiento/patología , Condicionamiento Psicológico/efectos de los fármacos , Miedo/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Hipocampo/efectos de los fármacos , Lipopolisacáridos/toxicidad , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Memoria/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Fragmentos de Péptidos/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , ARN Mensajero/metabolismo
12.
Crit Rev Immunol ; 27(2): 97-140, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17725499

RESUMEN

Orally applied nondigestible carbohydrates (NDC) have been associated with immune-modulating effects and other health benefits. The effects of prebiotic carbohydrates have recently received much attention, but other NDC have been reported to induce immune modulation as well. Many different effects have been shown on parameters of innate and specific immunity, mostly in animal experiments or in vitro. Data from clinical trials are limited, but promising studies have reported beneficial effects on mucosal and systemic immunity in humans. NDC are fermented to various degrees by the intestinal microbiota. Therefore, immune-modulatory properties have often been attributed to microbiota-dependent effects, especially in the case of prebiotic NDC. However, some NDC have been reported to bind to specific receptors on cells of the immune system, suggesting microbiota-independent, immune-modulatory effects play a role as well. This review aims to provide an overview of the published immune-modulatory effects in vitro and in vivo induced by NDC such as fructans, galactooligosaccharides, beta-glucans, pectins, and resistant starch. In addition, issues related to the underlying mechanisms are discussed: interaction between bacteria, their metabolites and the immune system, as well as direct effects of NDC via lectin receptors.


Asunto(s)
Carbohidratos/fisiología , Fibras de la Dieta , Suplementos Dietéticos , Factores Inmunológicos/fisiología , Animales , Humanos
13.
Neuroscience ; 331: 72-7, 2016 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-27320209

RESUMEN

For years, the prevailing hypothesis for Alzheimer's Disease (AD) has proposed a mechanism by which deposition of amyloid-beta (Aß) in the brain is independent of tau-pathologies and cognitive decline. However, despite extensive research on the disease, the mechanisms underlying the etiology of tau-pathology remain unknown. Previous research in our lab has shown that imatinib methanesulfonate (IM) blocks the peripheral production of Aß in response to LPS, thereby preventing the buildup of Aß in the hippocampus, and rescuing the cognitive dysfunction that normally follows. The present study aimed to examine the link between Aß and tau following inflammation, and to expand our understanding of how IM affects AD pathology. Specifically, we hypothesized that the IM-mediated inhibition of Aß production following inflammation would successfully protect against the hyperphosphorylation of tau (ptau). Here we show that 7days of LPS treatment in male C57BL/6J mice, which normally produces elevations in peripheral and central Aß, also produces hyperphosphorylation of tau. However, just as pre-treatment and concurrent treatment with IM blocks Aß production, it also blocks the phosphorylation of tau. In addition, 7days of LPS-induced inflammation and Aß production also leads to elevated total tau protein expression. Our results may provide support for the hypothesis that enhanced expression of tau following LPS administration is a protective measure by hippocampal neurons to compensate for the loss of the microtubule-stabilizing protein due to phosphorylation. More importantly, our results support the hypothesis that blocking the production of Aß that follows inflammation also leads to reduced tau phosphorylation, lending credence to a model in which Aß initiates tau phosphorylation.


Asunto(s)
Hipocampo/efectos de los fármacos , Hipocampo/inmunología , Mesilato de Imatinib/farmacología , Proteínas tau/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Western Blotting , Peso Corporal/efectos de los fármacos , Modelos Animales de Enfermedad , Lipopolisacáridos , Masculino , Ratones Endogámicos C57BL , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología
14.
Behav Brain Res ; 313: 219-225, 2016 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-27449203

RESUMEN

Alzheimer's disease is marked by the accumulation of the amyloid-beta (Aß) peptide, and increases in phosphorylation of the microtubule associated protein, tau. Changes in these proteins are considered responsible, in part, for the progressive neuronal degeneration and cognitive deficits seen in AD. We examined the effect of repeated consecutive peripheral poly I:C injections on cognitive deficits, central Aß, and phosphorylated tau accumulation, following three treatment durations: 7, 14, and 21 days. Forty-eight hours after the final injection, animals were trained in a contextual fear-conditioning paradigm, and tested 24h later. Immediately after testing, the hippocampus was collected to quantify Aß and phosphorylated tau accumulation. Results showed that, although poly I:C-induced Aß was significantly elevated at all time points examined, poly I:C only disrupted cognition after 14 and 21 days of administration. Moreover, elevations in phosphorylated tau were not seen until the 14-day time point. Interestingly, phosphorylated tau expression then declined at the 21-day time point. Finally, we demonstrated that Aß levels are a stronger predictor of cognitive dysfunction, explaining 37% of the variance, whereas phosphorylated tau levels only accounted for 0.2%. Taken together, these results support the hypothesis that inflammation-induced elevation in Aß disrupts cognition, independently of phosphorylated tau, and suggest that long-term administration of poly I:C may provide a model to investigate the contribution of long-term inflammation toward the development of Alzheimer's-like pathology.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Trastornos del Conocimiento/metabolismo , Disfunción Cognitiva/metabolismo , Hipocampo/metabolismo , Poli C/farmacología , Proteínas tau/metabolismo , Animales , Cognición/efectos de los fármacos , Cognición/fisiología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/tratamiento farmacológico , Disfunción Cognitiva/diagnóstico , Modelos Animales de Enfermedad , Hipocampo/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Fosforilación , Poli C/administración & dosificación
15.
Behav Brain Res ; 302: 171-4, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26778788

RESUMEN

Peripheral administration of lipopolysaccharide (LPS) elevates production of pro-inflammatory cytokines, and motivates the expression of sickness behaviors. In this study, we tested the ability of an LPS-derived adjuvant, monophosphoryl lipid A (MPLA), to prevent LPS-induced sickness behaviors in a burrowing paradigm. Testing occurred over a three-day period. Animals received a single injection of either MPLA or saline the first two days of testing. On day three, animals received either LPS or saline. Tissue from the dorsal hippocampus was collected for qRT-PCR to assess expression of IL-1ß and IL-4. Results indicate that, during the pre-treatment phase, administration of MPLA induces an immune response sufficient to trigger sickness behaviors. However, we observed that animals pre-treated with MPLA for two days were resistant to LPS-induced sickness behaviors on day three. Results from the qRT-PCR analysis indicated that LPS-treated animals pre-treated with MPLA expressed significantly less IL-1ß compared to LPS-treated animals pre-treated with saline. However, we did not observe a significant difference in IL-4 expression between groups. Therefore, results indicate that under the given parameters of the study, MPLA pre-treatment protects against LPS-induced sickness behaviors, at least in part, by decreasing expression of the pro-inflammatory cytokine IL-1ß.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Hipocampo/efectos de los fármacos , Conducta de Enfermedad/efectos de los fármacos , Interleucina-1beta/metabolismo , Lípido A/análogos & derivados , Adyuvantes Inmunológicos/administración & dosificación , Animales , Modelos Animales de Enfermedad , Esquema de Medicación , Interleucina-1beta/genética , Interleucina-4/genética , Interleucina-4/metabolismo , Lípido A/administración & dosificación , Lípido A/farmacología , Lipopolisacáridos/toxicidad , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/metabolismo
16.
Behav Brain Res ; 288: 50-3, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25823763

RESUMEN

Recent evidence suggests that inflammation-induced decrements in cognitive function can be mitigated via manipulation of excitatory or inhibitory transmission. We tested the ability of the inverse benzodiazepine agonist, MRK-016 (MRK) to protect against LPS-induced deficits in memory acquisition and consolidation, using a contextual fear conditioning (CFC) paradigm. In Experiment One, mice received lipopolysaccharide (LPS) and/or MRK injections prior to CFC training, and were then tested 24h after training. In Experiment Two, animals received similar treatment injections immediately after training, and were tested 24h later. Additionally, hippocampal samples were collected 4h after LPS injections and immediately after testing, to evaluate brain-derived neurotrophic factor (BDNF) and insulin-like growth factor 1 (IGF-1) mRNA expression. Results indicate that MRK can protect against LPS-induced learning/memory decrements in both paradigms. We also found, in both paradigms, that animals treated with LPS/Saline expressed significantly less BDNF mRNA when compared to Saline/Saline-treated animals 4h after LPS administration, but that MRK did not restore BDNF expression levels. Further, treatment administrations had no effect on IGF-1 mRNA expression at any collection time-point. In summary, MRK-016 can protect against LPS-induced deficits in memory acquisition and consolidation, in this hippocampus-dependent paradigm, though this protection occurs independently of recovery of BDNF expression.


Asunto(s)
Inflamación/tratamiento farmacológico , Isoxazoles/farmacología , Aprendizaje/efectos de los fármacos , Lipopolisacáridos/toxicidad , Memoria/efectos de los fármacos , Nootrópicos/farmacología , Triazinas/farmacología , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Condicionamiento Psicológico/efectos de los fármacos , Condicionamiento Psicológico/fisiología , Miedo/efectos de los fármacos , Miedo/fisiología , Reacción Cataléptica de Congelación/efectos de los fármacos , Reacción Cataléptica de Congelación/fisiología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Inflamación/metabolismo , Inflamación/psicología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Aprendizaje/fisiología , Masculino , Memoria/fisiología , Ratones Endogámicos C57BL , Neuroinmunomodulación/efectos de los fármacos , Neuroinmunomodulación/fisiología , ARN Mensajero/metabolismo , Factores de Tiempo
17.
Am J Clin Nutr ; 61(3): 524-7, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7872215

RESUMEN

The influence of three different feeding regimens on the activities of pancreatic lipase and trypsin in duodenal aspirates and on fecal nitrogen and fat excretion was studied in 35 healthy preterm infants after a 2-wk feeding period. Eleven infants received a standard preterm formula (without long-chain polyunsaturated fatty acids), 12 were fed with an experimental formula that only differed from the standard formula in fat blend composition (with long-chain polyunsaturated fatty acids), and 12 infants received human milk fortified with protein and energy to have similar nitrogen and energy contents as the two formulas. There were no significant differences in duodenal trypsin activities among the groups. In the group fed the standard formula, lipase activity was significantly lower than in the group fed the experimental formula (standard formula group: 8.4 +/- 3.5 kU/L; experimental formula group: 13.8 +/- 4.8 kU/L; P < 0.05) but there was no significant difference between the experimental formula group and the human milk group (15.1 +/- 4.2 kU/L). Fecal nitrogen as well as fat excretion were similar in the three feeding groups. The data suggest that dietary fat composition can influence the postnatal development of duodenal lipase activity in preterm infants.


Asunto(s)
Duodeno/metabolismo , Alimentos Infantiles , Recien Nacido Prematuro/metabolismo , Lipasa/metabolismo , Tripsina/metabolismo , Grasas de la Dieta/farmacología , Proteínas en la Dieta/farmacología , Duodeno/efectos de los fármacos , Edad Gestacional , Humanos , Recién Nacido , Leche Humana/química , Leche Humana/metabolismo , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Estudios Prospectivos
18.
Mech Ageing Dev ; 122(11): 1135-50, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11389929

RESUMEN

It has been suggested that moderate exercise may modulate the immune response in the elderly. We investigated whether moderate exercise had an effect on the immune response to viral infection in both young (2-4 months) and older (16-18 months) male BALB/cJ mice. Exercised (EX) mice ran on a treadmill for 8 weeks at a gradually increasing speed and duration whereas control (CON) mice were only handled briefly during each exercise session and then returned to their cages. Mice were infected with herpes simplex virus type 1 (HSV-1) 24 h post-exercise. Serum IgM anti-HSV antibody, HSV-1 specific Th1/Th2 cytokine production by spleen cells, and cytokine production by alveolar cells were measured 7 days post-infection. In the aged mice, exercise was associated with an enhanced production of the HSV-1 specific Th1-associated cytokines, interleukin (IL)-2 and interferon (IFN)-gamma, but had no effect on the Th2-associated cytokine IL-10 or IgM antibody. No effect of exercise was observed in young mice. IL-12 production was not altered by exercise, but aging was associated with altered IL-12 production in a tissue-specific manner. In conclusion, moderate exercise was associated with increased antigen-specific IL-2 and IFN-gamma production in response to viral challenge in older mice.


Asunto(s)
Envejecimiento/inmunología , Anticuerpos Antivirales/biosíntesis , Antígenos Virales/inmunología , Citocinas/biosíntesis , Esfuerzo Físico , Animales , Peso Corporal , Recuento de Células , Herpesvirus Humano 1/inmunología , Humanos , Inmunoglobulina M/biosíntesis , Interferón gamma/biosíntesis , Interleucina-10/biosíntesis , Interleucina-12/biosíntesis , Interleucina-2/biosíntesis , Interleucina-4/biosíntesis , Lipopolisacáridos/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Alveolos Pulmonares/citología , Bazo/citología , Células TH1/inmunología , Células Th2/inmunología
19.
Neurology ; 56(4): 514-9, 2001 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-11222797

RESUMEN

BACKGROUND: Pooled data from New Drug Applications (NDAs) submitted to the U.S. Food and Drug Administration (FDA) provide an opportunity to study the incidence of and risk factors for rare events. OBJECTIVE: To examine the incidence and causes of mortality in patients with epilepsy participating in clinical trials of antiepileptic drugs (AEDs); and to examine the incidence of and risk factors for sudden unexplained death in such patients. METHODS: Exposure data and death narratives were obtained from the NDAs of five recently reviewed AEDs. Deaths were classified as sudden unexplained, accidental, or other cause using the 1993 Burroughs-Wellcome expert panel criteria, and mortality rates were calculated for each category. Add-on trials were analyzed separately from monotherapy initiation trials. RESULTS: Among 9,144 patients in the add-on trial database, the all-cause and sudden unexplained mortality rates were 9.1 and 3.8 deaths per 1,000 person-years (124 and 52 deaths in 13,617.1 person-years of drug exposure). Sixty-five percent of all deaths were related to the underlying epilepsy. Of the examined risk factors, only age was associated with the incidence of sudden unexplained death. Among 1,293 patients in the monotherapy initiation trials, the all-cause and sudden unexplained mortality rates were 7.1 and 0 deaths per 1,000 person-years (7 and 0 deaths in 982.5 person-years of drug exposure). CONCLUSIONS: A large proportion of the deaths in the add-on cohort was attributable to epilepsy-related causes. Mortality due to sudden death in the add-on cohort falls into the high end of the reported range for patients with epilepsy. The difference in mortality due to sudden death between the add-on and monotherapy initiation cohorts suggests that disease severity is the primary determining factor for risk of sudden unexplained death.


Asunto(s)
Anticonvulsivantes/efectos adversos , Ensayos Clínicos como Asunto , Industria Farmacéutica , Epilepsia/mortalidad , Adolescente , Adulto , Anciano , Anticonvulsivantes/uso terapéutico , Causas de Muerte , Niño , Preescolar , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Factores de Riesgo
20.
J Neuroimmunol ; 113(2): 236-9, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11164907

RESUMEN

In Wistar rats, reexposure to a novel conditioned stimulus (CS) previously paired with a protein antigen, hen egg lysozyme (HEL) on a single conditioning trial increased anti-HEL IgG levels relative to conditioned rats that were not reexposed to the CS, conditioned rats that were preexposed to the CS, and nonconditioned rats. These results confirm previous findings that a single exposure to a CS associated with immunization is sufficient to elicit an antibody response upon subsequent reexposure to the CS in the absence of exogenous antigen.


Asunto(s)
Anticuerpos/análisis , Condicionamiento Psicológico/fisiología , Muramidasa/inmunología , Animales , Inmunoglobulina G/análisis , Masculino , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA