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1.
Hum Reprod ; 35(3): 573-582, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32154565

RESUMEN

STUDY QUESTION: What are couples' decisional conflicts around family-building approaches before and after seeking a specialty consultation for infertility? SUMMARY ANSWER: Decisional conflict is high among couples before an initial specialty consultation for infertility; on average, women resolved decisional conflict more quickly than men. WHAT IS KNOWN ALREADY: Couples have multiple options for addressing infertility, and decisional conflict may arise due to lack of information, uncertainty about options and potential risks or challenges to personal values. STUDY DESIGN, SIZE, DURATION: We conducted a total of 385 interviews and 405 surveys for this longitudinal, mixed-methods cohort study of 34 opposite-sex couples who sought a new reproductive specialty consultation (n = 68), who enrolled before the initial consultation and were followed over 12 months. PARTICIPANTS/MATERIALS, SETTING, METHODS: The in-depth, semi-structured interviews included questions about information gathering, deliberation and decision-making, and self-administered surveys included the Decisional Conflict Scale (DCS), at six time points over 12 months. A DCS total score of 25 is associated with implementing a decision, and higher scores indicate more decisional conflict. A systematic content analysis of interview transcripts identified major themes. Paired t tests identified differences in DCS between women and men within couples. Linear mixed models predicted changes in DCS over time, adjusting for sociodemographic and fertility-related factors. MAIN RESULTS AND THE ROLE OF CHANCE: The major qualitative themes were communication with partners, feeling supported and/or pressured in decision (s), changing decisions over time and ability to execute a desired decision. Average DCS scores were highest before the initial consultation. Within couples, men had significantly higher decisional conflict than women pre-consultation (48.9 versus 40.2, P = 0.037) and at 2 months (28.9 versus 22.1, P = 0.015), but differences at other time points were not significant. In adjusted models, predicted DCS scores declined over time, with women, on average, reaching the DCS threshold for implementing a decision at 2 months while for men it was not until 4 months. LIMITATIONS, REASONS FOR CAUTION: This is a convenience sample from a single center, and generalizability may be limited. WIDER IMPLICATIONS OF THE FINDINGS: Understanding how couples discuss and make decisions regarding family-building could improve the delivery of patient-centered infertility care. Our findings are the first to prospectively explore decisional conflict at multiple time points in both men and women; the observed gender differences underlie the importance of supporting both partners in clinical decision-making for infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Institute of Child Health and Human Development under Grant [R21HD071332], the Research and Education Program Fund, of the Advancing a Healthier Wisconsin endowment at Medical College of Wisconsin, the National Research Service Award under Grant [T32 HP10030] and the use of REDCap for data collection from the National Center for Advancing Translational Sciences, National Institutes of Health under Grant through [8UL1TR000055]. The authors have no competing interests.


Asunto(s)
Infertilidad , Niño , Estudios de Cohortes , Emociones , Femenino , Humanos , Infertilidad/terapia , Estudios Longitudinales , Masculino , Encuestas y Cuestionarios , Estados Unidos
2.
Phys Chem Chem Phys ; 17(3): 2104-12, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25482360

RESUMEN

The Birmingham cluster genetic algorithm is a package that performs global optimisations for homo- and bimetallic clusters based on either first principles methods or empirical potentials. Here, we present a new parallel implementation of the code which employs a pool strategy in order to eliminate sequential steps and significantly improve performance. The new approach meets all requirements of an evolutionary algorithm and contains the main features of the previous implementation. The performance of the pool genetic algorithm is tested using the Gupta potential for the global optimisation of the Au10Pd10 cluster, which demonstrates the high efficiency of the method. The new implementation is also used for the global optimisation of the Au10 and Au20 clusters directly at the density functional theory level.

3.
J Neuroimmunol ; 246(1-2): 69-77, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22498097

RESUMEN

BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear hormone receptor that has been shown to have anti-inflammatory and matrix metalloproteinase (MMP) inhibitor properties. PPARγ agonists have been shown to have neuroprotective effects in various neurodegeneration models where inflammation is implicated, including models of Parkinson's disease. However, no studies have looked at the effects of partial PPARγ agonists. EXPERIMENTAL APPROACH: The neuroprotective effects of the PPARγ full agonist, pioglitazone (20 mg/kg), partial PPARγ agonist GW855266X (15 mg/kg) and PPAR-δ full agonist GW610742X (10 mg/kg) were investigated in the 6-hydroxydopamine (6-OHDA) model of Parkinson's disease when administered prior to or post 6-OHDA lesioning. The integrity of the nigrostriatal system was assessed by assessing the numbers dopaminergic neurons in the substantia nigra (SN) and by assessing striatal dopamine content. The degree of microglia activation in the SN was also immunohistochemistry assessed utilizing the marker OX-6 for activated microglia and CD-68 a marker for phagocytic microglia. Additionally we performed immunocytochemistry for MMP3 in the SN. Finally, we investigated whether a period of drug withdrawal for a further 7 days affected the neuroprotection produced by the PPARγ agonists. KEY RESULTS: Both pioglitazone and GW855266X protected against 6-OHDA induced loss of dopaminergic neurons in the substantia nigra and depletion of striatal dopamine when administered orally twice daily for either 1) 7 day prior to and 7 days post lesioning or 2) for 7 days starting 2 days post lesioning when neurons will be severely traumatized. 6-OHDA lesioning was associated with an increase in microglia activation and in numbers of MMP-3 immunoreactive cells which was attenuated by pioglitazone and GW855266X. Neuroprotective effects were not replicated using the PPARδ agonist GW610742X. Subsequent withdrawal of both pioglitazone and GW855266X, for a further 7 days negated any neuroprotective effect suggesting that long-term administration may be required to attenuate the inflammatory response. CONCLUSIONS AND IMPLICATIONS: For the first time a partial PPAR-γ agonist has been shown to be neuroprotectory when administered post lesioning in a parkinsonian model. Effects may be via the inhibition of microglial and MMP activation and support further research.


Asunto(s)
Neuronas Dopaminérgicas/inmunología , Inhibidores de Crecimiento/farmacología , Inhibidores de la Metaloproteinasa de la Matriz , Microglía/inmunología , PPAR gamma/agonistas , Trastornos Parkinsonianos/inmunología , Inhibidores de Proteasas/farmacología , Animales , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/enzimología , Masculino , Metaloproteinasa 3 de la Matriz/biosíntesis , Microglía/efectos de los fármacos , Microglía/enzimología , Fármacos Neuroprotectores/farmacología , Oxidopamina/toxicidad , PPAR delta/agonistas , PPAR delta/farmacología , PPAR gamma/farmacología , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/enzimología , Ratas , Ratas Sprague-Dawley
4.
Naunyn Schmiedebergs Arch Pharmacol ; 380(4): 311-25, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19690836

RESUMEN

This report examines the effect of the transient receptor potential vanilloid 1 receptor antagonist SB-705498 on neurotransmission and inflammation-induced sensitisation in the trigeminovascular sensory system. A single-neuron electrophysiological animal model for neurovascular head pain was used to evaluate dural and facial noxious inputs and the effects of SB-705498 administered by intravenous (i.v.) injection. Electrical and mechanical stimulation of the dura mater and the facial skin activated second-order neurons in the trigeminal nucleus caudalis of cats, with A-delta latencies. Intravenous injection of SB-705498 (2 mg kg(-1)) produced a slowly developing and long-lasting suppression of responses to dural and skin stimulation. Maximum suppression occurred by 1 h and reached 41% for dura and 24% for skin. Intravenous injection of drug vehicle did not produce significant suppression of responses to stimulation of either dura or skin. Intravenous injection of SB-705498 produced a brief and small rise in blood pressure and dural blood flow, which both returned to normal before suppression of the responses to stimulation became manifest. Application of "inflammatory soup" to the dura mater produced a pronounced increase in dural blood flow and induced a slowly developing increase in the responses of neurons to both electrical and mechanical stimulations of their facial and dural receptive fields. This sensitisation reached a maximum in 60-90 min, at which time responses had risen to approximately twice that of control levels seen before the application of inflammatory soup. Intravenous injection of SB-705498 subsequent to the development of sensitisation produced a slowly developing, prolonged and statistically significant reversal of the sensitisation induced by inflammatory soup. Maximum reversal of sensitisation to electrical stimulation occurred by 150-180 min, when responses had fallen to, or below, control levels. At 70-85 min following injection of SB-705498, the responses of previously sensitised neurons to mechanical stimulation of dura mater and facial receptive field had also returned to near control levels. SB-705498 was also able to prevent the development of sensitisation; application of inflammatory soup to the dura mater induced a slowly developing increase in the responses of neurons to electrical stimulation of the skin and dura mater in cats which had received an i.v. injection of vehicle for SB-705498 but not in cats which had received the active drug. Blood levels of SB-705498 were maximal immediately following i.v. injection and declined over the following 2 h. Significant brain levels of SB-705498 were maintained for up to 9 h. These results suggest that SB-705498 may be an effective suppressant and reversal agent of the sensitisation to sensory input which follows inflammation in the trigeminovascular sensory distribution but may not be particularly useful in blocking primary pain processes such as migraine headache. SB-705498 could thus potentially prevent, modify or reverse the cutaneous trigeminal allodynia seen in certain migraine conditions, especially "transformed" migraine.


Asunto(s)
Analgésicos/farmacología , Duramadre/irrigación sanguínea , Inflamación/tratamiento farmacológico , Trastornos Migrañosos/tratamiento farmacológico , Dolor/tratamiento farmacológico , Pirrolidinas/farmacología , Piel/inervación , Transmisión Sináptica/efectos de los fármacos , Canales Catiónicos TRPV/antagonistas & inhibidores , Nervio Trigémino/efectos de los fármacos , Urea/análogos & derivados , Analgésicos/administración & dosificación , Analgésicos/sangre , Animales , Presión Sanguínea/efectos de los fármacos , Gatos , Circulación Cerebrovascular/efectos de los fármacos , Modelos Animales de Enfermedad , Estimulación Eléctrica , Potenciales Evocados , Cara , Inflamación/metabolismo , Inflamación/fisiopatología , Mediadores de Inflamación/metabolismo , Inyecciones Intravenosas , Trastornos Migrañosos/metabolismo , Trastornos Migrañosos/fisiopatología , Fibras Nerviosas Mielínicas/efectos de los fármacos , Fibras Nerviosas Mielínicas/metabolismo , Dolor/metabolismo , Dolor/fisiopatología , Dimensión del Dolor , Umbral del Dolor/efectos de los fármacos , Pirrolidinas/administración & dosificación , Pirrolidinas/sangre , Tiempo de Reacción/efectos de los fármacos , Canales Catiónicos TRPV/metabolismo , Factores de Tiempo , Núcleo Caudal del Trigémino/efectos de los fármacos , Núcleo Caudal del Trigémino/metabolismo , Núcleo Caudal del Trigémino/fisiopatología , Nervio Trigémino/metabolismo , Nervio Trigémino/fisiopatología , Urea/administración & dosificación , Urea/sangre , Urea/farmacología
5.
Histol Histopathol ; 23(1): 67-76, 2008 01.
Artículo en Inglés | MEDLINE | ID: mdl-17952859

RESUMEN

A transgenic mouse bearing mutant transgenes linked to familial forms of Alzheimer's disease (AD) for the amyloid precursor protein and presenilin-1 (TASTPM) showed Abeta plaque deposition and age-related histological changes in associated brain pathology. The Abeta present was of multiple forms, including species with a C-terminus at position 40 or 42, as well as an N-terminus at position 1 or truncated in a pyro-3-glutamate form. Endogenous rodent Abeta was also present in the deposits. Laser capture microdissection extracts showed that multimeric forms of Abeta were present in both plaque and tissue surrounding plaques. Associated with the Abeta deposits was evidence of an inflammatory response characterised by the presence of astrocytes. Also present in close association with the deposits was phosphorylated tau and cathepsin D immunolabelling. The incidence of astrocytes and of phosphorylated tau and cathepsin D load showed that both of these potential disease markers increased in parallel to the age of the mice and with Abeta deposition. Immunohistochemical labelling of neurons in the cortex and hippocampus of TASTPM mice suggested that the areas of Abeta deposition were associated with the loss of neurons. TASTPM mice, therefore, exhibit a number of the pathological characteristics of disease progression in AD and may provide a means for assessment of novel therapeutic agents directed towards modifying or halting disease progression.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Presenilina-1/metabolismo , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Catepsina D/genética , Catepsina D/metabolismo , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Hipocampo/metabolismo , Hipocampo/patología , Masculino , Ratones , Ratones Transgénicos , Presenilina-1/genética , Proteínas tau/genética , Proteínas tau/metabolismo
6.
Radiat Oncol ; 1: 7, 2006 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-16722599

RESUMEN

BACKGROUND: Preliminary very encouraging clinical results of intensity modulated radiation therapy (IMRT) in Head Neck Cancer (HNC) are available from several large centers. Tumor control rates seem to be kept at least at the level of conventional three-dimensional radiation therapy; the benefit of normal tissue preservation with IMRT is proven for salivary function. There is still only limited experience with IMRT using simultaneously integrated boost (SIB-IMRT) in the head and neck region in terms of normal tissue response.The aim of this work was (1) to establish tumor response in HNC patients treated with SIB-IMRT, and (2) to assess tissue tolerance following different SIB-IMRT schedules. RESULTS: Between 1/2002 and 12/2004, 115 HNC patients have been curatively treated with IMRT. 70% received definitive IMRT (dIMRT), 30% were postoperatively irradiated. In 78% concomitant chemotherapy was given. SIB radiation schedules with 5-6 x 2 Gy/week to 60-70 Gy, 5 x 2.2 Gy/week to 66-68.2 Gy (according to the RTOG protocol H-0022), or 5 x 2.11 Gy/week to 69.6 Gy were used. After mean 18 months (10-44), 77% of patients were alive with no disease. Actuarial 2-year local, nodal, and distant disease free survival was 77%, 87%, and 78%, respectively. 10% were alive with disease, 10% died of disease. 20/21 locoregional failures occurred inside the high dose area. Mean tumor volume was significantly larger in locally failed (63 cc) vs controlled tumors (32 cc, p <0.01), and in definitive (43 cc) vs postoperative IMRT (25 cc, p <0.05); the locoregional failure rate was twofold higher in definitively irradiated patients. Acute reactions were mild to moderate and limited to the boost area, the persisting grade 3/4 late toxicity rate was low with 6%. The two grade 4 reactions (dysphagia, laryngeal fibrosis) were observed following the SIB schedule with 2.2 Gy per session. CONCLUSION: SIB-IMRT in HNC using 2.0, 2.11 or 2.2 Gy per session is highly effective and safe with respect to tumor response and tolerance. SIB with 2.2 Gy is not recommended for large tumors involving laryngeal structures.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta en la Radiación , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Inducción de Remisión , Resultado del Tratamiento
7.
Neurosci Lett ; 399(1-2): 51-6, 2006 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-16481104

RESUMEN

We have studied the effect of key neurotrophic factors (NTFs) on morphology, levels of the vanilloid receptor-1 (TRPV1) and responses to capsaicin in adult human sensory neurons in vitro. Avulsed dorsal root ganglia (DRG, n = 5) were cultured with or without a combination of nerve growth factor (NGF), glial cell (line)-derived growth factor (GDNF) and neurotrophin3 (NT3) for 5 days. In the absence of NTFs, the diameter of neurons ranged from 20 to 100 microm (mean 42 +/- 4 microm). Adding NTFs caused a significant increase in neuronal sizes, up to 120 microm (mean diameter 62 +/- 5 microm, P < 0.01, t-test), an overall 35% increase of TRPV1-positive neurons (P < 0.003), and notably of large TRPV1-positive neurons > 80 microm (P < 0.05). Responses to capsaicin were significantly enhanced with calcium ratiometry (P < 0.0001). Short duration (1h) exposure of dissociated sensory neurons to NTFs increased numbers of TRPV1-positive neurons, but not of TRPV3, Nav 1.8 and IK1 and the morphological size-distribution remained similar to intact post-mortem DRG neurons. NTFs thus increase size, elevate TRPV1 levels and enhance capsaicin responses in cultured human DRG neurons; these changes may relate to pathophysiology in disease states, and provide an in vitro model to study novel analgesics.


Asunto(s)
Capsaicina/farmacología , Ganglios Espinales/citología , Factores de Crecimiento Nervioso/metabolismo , Neuronas Aferentes/efectos de los fármacos , Canales Catiónicos TRPV/biosíntesis , Adulto , Tamaño de la Célula , Células Cultivadas , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Humanos , Masculino , Canal de Sodio Activado por Voltaje NAV1.8 , Factor de Crecimiento Nervioso/metabolismo , Neuronas Aferentes/citología , Neuronas Aferentes/metabolismo , Neurotrofina 3/metabolismo , Canales de Potasio Calcio-Activados/biosíntesis , Canales de Sodio/biosíntesis
8.
J Urol ; 174(3): 977-82; discussion 982-3, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16094018

RESUMEN

PURPOSE: Botulinum neurotoxin type A (BoNT/A) is effective in the treatment of intractable detrusor overactivity (DO). In addition to its known inhibitory effect on presynaptic release of acetylcholine by motor terminals, there is increasing evidence that BoNT/A may affect sensory fibers. We investigated a possible effect of BoNT/A on human bladder afferent mechanisms by studying the sensory receptors P2X3 and TRPV1 in biopsies from patients with neurogenic or idiopathic DO. MATERIALS AND METHODS: A total of 38 patients (22 with neurogenic DO, 16 with idiopathic DO) with intractable DO were treated with intradetrusor BoNT/A, and bladder biopsies were taken at 4 and 16 weeks. Urodynamics and voiding diary were also recorded. Specimens were studied immunohistochemically for P2X3, TRPV1 and the pan-neuronal marker PGP9.5, in comparison with controls. RESULTS: P2X3-immunoreactive and TRPV1-immunoreactive (-IR) fibers were decreased at 4 weeks after BoNT/A, and more significantly at 16 weeks (paired t test p=0.0004 and p=0.0008, respectively), when significant improvements were observed in clinical and urodynamic parameters. P2X3-IR fiber decrease was significantly correlated with reduction of urgency episodes at 4 and 16 weeks (p=0.0013 at 4 weeks and p=0.02 at 16 weeks), but not maximum cystometric capacity or detrusor pressures. TRPV1-IR fiber decrease showed a similar trend. PGP9.5-IR suburothelial fibers remained unchanged after treatment at both followups (p=0.85 and p=0.21 at 4 and 16 weeks, respectively). Urothelial cell P2X3-IR and TRPV1-IR also appeared unchanged. CONCLUSIONS: Decreased levels of sensory receptors P2X3 and/or TRPV1 may contribute to the clinical effect of BoNT/A in detrusor overactivity.


Asunto(s)
Toxinas Botulínicas Tipo A/administración & dosificación , Canales Iónicos/efectos de los fármacos , Hipertonía Muscular/tratamiento farmacológico , Fibras Nerviosas/efectos de los fármacos , Fármacos Neuromusculares/administración & dosificación , Receptores Purinérgicos P2/efectos de los fármacos , Células Receptoras Sensoriales/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Vejiga Urinaria Neurogénica/tratamiento farmacológico , Vejiga Urinaria/inervación , Incontinencia Urinaria/tratamiento farmacológico , Adulto , Vías Aferentes/efectos de los fármacos , Anciano , Biopsia , Toxinas Botulínicas Tipo A/efectos adversos , Cistoscopía , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Técnicas para Inmunoenzimas , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Hipertonía Muscular/patología , Fibras Nerviosas/patología , Fibras Nerviosas Amielínicas/efectos de los fármacos , Fibras Nerviosas Amielínicas/patología , Fármacos Neuromusculares/efectos adversos , Receptores Purinérgicos P2X3 , Sensibilidad y Especificidad , Canales Catiónicos TRPV , Resultado del Tratamiento , Vejiga Urinaria/patología , Vejiga Urinaria Neurogénica/patología , Incontinencia Urinaria/patología , Urodinámica/efectos de los fármacos , Urotelio/inervación , Urotelio/patología
9.
Eur J Surg Oncol ; 31(6): 667-74, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16100781

RESUMEN

As early as in 1982, the European Organisation for Research and Treatment of Cancer Radiotherapy Group established a quality assurance programme. In the course of 20 years, quality assurance procedures have become a vast and important part of the activities of the group. Today, the membership committee uses standard procedures based on minimal requirements to evaluate current members and new membership applications. Moreover, for every new trial, specific quality assurance procedures are an integral part of the preparation of the protocol and executed under the responsibility of the study coordinator. With the growing complexity of the radiotherapy techniques used in the framework of the more recent trials, quality assurance procedures have also become more complex including trial specific phantom based measurements. Future ways to evaluate all steps of the radiotherapy process using a common platform connecting all users with the internet are currently under development.


Asunto(s)
Neoplasias/radioterapia , Garantía de la Calidad de Atención de Salud/organización & administración , Oncología por Radiación/normas , Ensayos Clínicos como Asunto , Europa (Continente) , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Desarrollo de Programa , Garantía de la Calidad de Atención de Salud/historia , Garantía de la Calidad de Atención de Salud/tendencias , Sociedades Médicas
10.
Lab Chip ; 5(3): 318-25, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15726208

RESUMEN

We report a Micro Throttle Pump (MTP) which has been shown to pump 5 microm diameter polystyrene beads at a concentration of 4.5 x 10(7) beads ml(-1). This new MTP design is constructed in a straightforward manner and actuated by a single piezoelectric (PZT) element. Maximum flow rates at 800 Hz drive frequency of 132 microl min(-1) with water and 108 microl min(-1) with a bead suspension were obtained. Maximum back-pressures of 6 kPa were observed in both cases. The reported MTP employs specific location of distinct internal microfluid structures cast in a single compliant elastomeric substrate to exploit the opposing directions of flexure of regions of a piezoelectric-glass composite bonded to the elastomer. By this novel means, distinct flexural regions, exhibiting compressive and tensile stresses respectively, allow both the pump's integrated input and output throttles and its pump chamber to be actuated concurrently by a single PZT. To support MTP design we also report the characterisation of an individual throttle's resistance as a function of actuator deflection and discuss the underlying mechanism of the throttling effect.


Asunto(s)
Elastómeros/química , Microquímica/instrumentación , Microquímica/métodos , Microfluídica/instrumentación , Microfluídica/métodos , Estimulación Física/instrumentación , Diseño de Equipo , Estudios de Evaluación como Asunto , Poliestirenos/química , Propiedades de Superficie , Transportes
11.
Neurogastroenterol Motil ; 17(1): 102-11, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15670270

RESUMEN

A variety of inflammatory mediators and local metabolites, have been implicated in the sensitivity of intestinal afferent fibres to brief periods of ischaemia and reperfusion. As yet, the contribution of the vanilloid transient receptor potential (TRPV)1 receptor to the response to intestinal ischaemia remains undetermined. In the present study, the effect of pretreatment with the competitive TRPV1 antagonist capsazepine and the non-selective TRPV channel antagonist ruthenium red, on the mesenteric afferent fibre response to ischaemia was examined. In control animals there was a reproducible biphasic increase in whole nerve afferent fibre activity during two brief periods of ischaemia. Treatment with ruthenium red significantly attenuated the early phase increase in afferent fibre activity during ischaemia. However, capsazepine treatment did not significantly alter the afferent fibre response to either ischaemia or reperfusion. Further experiments in chronically vagotomized animals indicated that the early phase response to ischaemia was mediated via vagal afferent fibres. The mechanism via which ruthenium red selectively inhibited vagal afferent fibres during ischaemia is unknown, but it does not appear to involve blockade of the TRPV1 receptor.


Asunto(s)
Capsaicina/análogos & derivados , Isquemia/fisiopatología , Yeyuno/irrigación sanguínea , Yeyuno/inervación , Fibras Nerviosas/efectos de los fármacos , Neuronas Aferentes/efectos de los fármacos , Rojo de Rutenio/farmacología , Nervio Vago/fisiología , Animales , Capsaicina/farmacología , Masculino , Ratas , Ratas Sprague-Dawley , Receptores de Droga/antagonistas & inhibidores , Receptores de Droga/efectos de los fármacos , Daño por Reperfusión/fisiopatología , Vagotomía
12.
Clin Oncol (R Coll Radiol) ; 16(7): 457-60, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15490806

RESUMEN

AIMS: Postoperative interstitial brachytherapy of limbs is challenging, because it is difficult to deliver a conformal dose to the tumour bed. We developed and assessed a new surgical fixation system for positioning guiding tubes in interstitial brachytherapy in order to achieve favourable geometry. MATERIALS AND METHODS: A 28-year-old patient was treated with postoperative interstitial brachytherapy boost followed by external radiotherapy after the 11th recurrence of a desmoid tumour in the forearm. On the basis of preoperative imaging data, customised resorbable templates made of polydioxanone (PDS) were cut to fit in the space left by the resected tumour. These were strategically positioned in the tumour bed during surgery. In order to hold the brachytherapy-guiding tubes parallel for the duration of treatment, they were passed through a series of holes bored into the templates. RESULTS: Fixing the guiding tubes with PDS templates resulted in a fixed geometry, and thus in an optimal dose distribution with only little additional dose optimisation needed by the brachytherapy treatment planning system. An optimised dose to the tumour bed, and a reduction of dose to critical normal tissues, is achievable with this template system for sarcomas located between osseous structures. CONCLUSION: The PDS templates offer a more rigid fixation of the guiding tubes in relation to the surrounding anatomy even after the operation cavity has been closed. A tailored dose distribution can be achieved, thus reducing possible side-effects. Additionally, because of the self-resorbable nature of the material, a re-operation for template removal is not necessary. The potential advantages of this method are being further investigated.


Asunto(s)
Braquiterapia/instrumentación , Braquiterapia/métodos , Sarcoma/radioterapia , Neoplasias de los Tejidos Blandos/radioterapia , Adulto , Antebrazo/patología , Humanos , Radioterapia Adyuvante , Sarcoma/patología , Neoplasias de los Tejidos Blandos/patología
13.
Analyst ; 129(9): 829-34, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15343398

RESUMEN

We report a reciprocating microfluidic pump, the Micro Throttle Pump (MTP), constructed in a relatively uncomplicated manner from glass and microstructured poly(dimethylsiloxane)(PDMS). Unconventionally, the MTP employs throttling of fluid flow as distinct from fully-closing valve structures. Accordingly, this technique offers the prospect of solid-phase suspension tolerance. The reported MTP employs piezoelectrically (PZT) actuated deformation of flow constrictions (throttles) fabricated from PDMS at the two ports of a central, PZT actuated pump chamber. By appropriate time-sequencing of the individual PZTs' actuation, pumping can be induced in either direction. PDMS' elasticity further facilitates throttle operation by virtue of allowing significant PZT flexure that is substantially independent of the underlying PDMS microstructure. In contrast, in a rigid substrate such as silicon, deformation is constrained to where underlying microstructured cavities exist and this restricts design options. We describe the construction and performance of a prototype MTP capable of pumping 300 microl min(-1) or alternatively generating a back-pressure of 5.5 kPa. Preliminary modelling of MTP operation is also presented.

14.
Eur J Neurosci ; 19(5): 1421-4, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15016100

RESUMEN

Daily body temperature (DBT) rhythm of mice lacking one of the transient receptor potential (TRP) family of proteins, the capsaicin receptor or TRPV1, was recorded by biotelemetry and found to have significantly higher amplitude than that of wild-type mice. Capsaicin-desensitized wild-mice exhibited an even higher DBT amplitude than did TRPV1 deficient mice. A standard heat load (radiant temperature of 36-37 degrees C) resulted in similar rises in body core temperature in wild-type mice and in TRPV1 deficient mice, while capsaicin-desensitized wild-type mice exhibited a robust heat-intolerance. The lack of TRPV1 slightly modifies amplitude of daily body temperature rhythm but does not seem to influence physiological heat defence in mice. In vivo evidence for a TRP protein functioning in the physiological heat-defence range is still lacking.


Asunto(s)
Temperatura Corporal/fisiología , Capsaicina/farmacología , Ritmo Circadiano/fisiología , Calor , Receptores de Droga/deficiencia , Animales , Temperatura Corporal/efectos de los fármacos , Ritmo Circadiano/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Droga/agonistas , Receptores de Droga/genética
15.
Neuropharmacology ; 46(1): 133-49, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14654105

RESUMEN

Vanilloid receptor-1 (TRPV1) is a non-selective cation channel, predominantly expressed by peripheral sensory neurones, which is known to play a key role in the detection of noxious painful stimuli, such as capsaicin, acid and heat. To date, a number of antagonists have been used to study the physiological role of TRPV1; however, antagonists such as capsazepine are somewhat compromised by non-selective actions at other receptors and apparent modality-specific properties. SB-366791 is a novel, potent, and selective, cinnamide TRPV1 antagonist isolated via high-throughput screening of a large chemical library. In a FLIPR-based Ca(2+)-assay, SB-366791 produced a concentration-dependent inhibition of the response to capsaicin with an apparent pK(b) of 7.74 +/- 0.08. Schild analysis indicated a competitive mechanism of action with a pA2 of 7.71. In electrophysiological experiments, SB-366791 was demonstrated to be an effective antagonist of hTRPV1 when activated by different modalities, such as capsaicin, acid or noxious heat (50 degrees C). Unlike capsazepine, SB-366791 was also an effective antagonist vs. the acid-mediated activation of rTRPV1. With the aim of defining a useful tool compound, we also profiled SB-366791 in a wide range of selectivity assays. SB-366791 had a good selectivity profile exhibiting little or no effect in a panel of 47 binding assays (containing a wide range of G-protein-coupled receptors and ion channels) and a number of electrophysiological assays including hippocampal synaptic transmission and action potential firing of locus coeruleus or dorsal raphe neurones. Furthermore, unlike capsazepine, SB-366791 had no effect on either the hyperpolarisation-activated current (I(h)) or Voltage-gated Ca(2+)-channels (VGCC) in cultured rodent sensory neurones. In summary, SB-366791 is a new TRPV1 antagonist with high potency and an improved selectivity profile with respect to other commonly used TRPV1 antagonists. SB-366791 may therefore prove to be a useful tool to further study the biology of TRPV1.


Asunto(s)
Anilidas/farmacología , Capsaicina/análogos & derivados , Cinamatos/farmacología , Péptidos y Proteínas de Señalización Intracelular , Potenciales de la Membrana/efectos de los fármacos , Receptores de Droga/antagonistas & inhibidores , 8-Hidroxi-2-(di-n-propilamino)tetralin/farmacología , Ácidos/farmacología , Anilidas/química , Compuestos de Anilina/metabolismo , Animales , Calcio/metabolismo , Capsaicina/farmacología , Proteínas Portadoras/farmacología , Línea Celular , Cinamatos/química , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Embrión de Mamíferos , Agonistas de Aminoácidos Excitadores/farmacología , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Calor , Humanos , Riñón , N-Metilaspartato/farmacología , Neuropéptidos/farmacología , Norepinefrina/farmacología , Orexinas , Técnicas de Placa-Clamp/métodos , Unión Proteica/efectos de los fármacos , Ensayo de Unión Radioligante/métodos , Ratas , Receptores de Droga/química , Agonistas de Receptores de Serotonina/farmacología , Xantenos/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/farmacología
16.
Health Educ Res ; 18(5): 568-79, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14572017

RESUMEN

This paper explores the need for better links between research and practice in relation to work with children and health inequalities. Despite continuing discussion about the need to improve dissemination of research activity in general, study of this area remains largely neglected. As a result, despite the rhetoric, the research and practice gap continues to exist. An attempt to remedy this was undertaken through the support of a user fellowship as part of the UK Economic and Social Research Council Health Variations Programme. The paper describes a number of activities that were undertaken during the fellowship, and discusses the implications of these for improving connections and minimizing the research and practice 'gap'. It argues that a need exists for researchers to develop innovative dissemination strategies and suggests that potential exists for an interactive model of dissemination. Such a model implies a more active role for users of research in the shaping of research agendas.


Asunto(s)
Política de Salud , Accesibilidad a los Servicios de Salud , Investigación sobre Servicios de Salud , Difusión de la Información , Justicia Social , Niño , Protección a la Infancia , Medicina Basada en la Evidencia , Humanos , Formulación de Políticas , Calidad de la Atención de Salud , Escocia
17.
Eur J Cancer ; 39(14): 2035-42, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12957458

RESUMEN

To assess consistency among participants in an European Organisation for Research and Treatment of Cancer (EORTC) phase III trial randomising between irradiation and no irradiation of the internal mammary and medial supraclavicular (IM-MS) lymph nodes, all participating institutes were invited to send data from 3 patients in each arm as soon as they started accrual. The evaluation focused on eligibility, compliance with the radiotherapy guidelines, treatment techniques and dose prescription to the IM-MS region. Nineteen radiotherapy departments provided a total of 111 cases, all being eligible. Minor discrepancies were found in the surgery and pathology data in almost half the patients. Major radiotherapy protocol deviations were very limited: 2 cases of unwarranted irradiation of the supraclavicular region and a significant dose deviation to the internal mammary region in 5 patients. The most frequently observed minor protocol deviation was the absence of delineation of the target volumes in 80% of the patients. By detecting systematic protocol deviations in an early phase of the trial, recommendations made to all the participating institutes should improve the interinstitutional consistency and promote a high-quality treatment.


Asunto(s)
Neoplasias de la Mama/radioterapia , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Neoplasias de la Mama/patología , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Irradiación Linfática/métodos , Calidad de la Atención de Salud , Dosificación Radioterapéutica , Resultado del Tratamiento
18.
Lancet ; 361(9355): 385-91, 2003 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-12573376

RESUMEN

BACKGROUND: Faecal urgency and incontinence with rectal hypersensitivity is a distressing, unexplained disorder that is inadequately treated. We aimed to determine whether expression of the heat and capsaicin receptor vanilloid receptor 1 (TRPV1 or VR1) was changed in rectal sensory fibres, and to correlate nerve fibre density with sensory abnormalities. METHODS: We compared full-thickness rectal biopsy samples from nine patients with physiologically characterised rectal hypersensitivity with tissue samples from 12 controls. Sensory thresholds to rectal balloon distension and heating the rectal mucosa were measured before biopsy. We assessed specimens with immunohistochemistry and image analysis using specific antibodies to TRPV1; nerve growth factor (NGF) receptor tyrosine kinase A; glial cell line-derived neurotrophic factor (GDNF); neuropeptides calcitonin gene-related peptide (CGRP) and substance P; the related vanilloid receptor-like protein (VRL) 2; glial markers S-100 and glial fibrillary acid protein (GFAP); and the nerve structural marker peripherin. FINDINGS: In rectal hypersensitivity, nerve fibres immunoreactive to TRPV1 were increased in muscle, submucosal, and mucosal layers: in the mucosal layer, the median% area positive was 0.44 (range 0.30-0.59) in patients who were hypersensitive and 0.11 (0.00-0.21) in controls (p=0.0005). The numbers of peripherin-positive fibres also increased in the mucosal layer (hypersensitive 3.00 [1.80-6.50], controls 1.20 [0.39-2.10]: (p=0.0002). The increase in TRVP1 correlated significantly with the decrease in rectal heat (p=0.03) and the distension (p=0.02) sensory thresholds. The thresholds for heat and distension were also significantly correlated (p=0.0028). Expression of nerve fibres positive for GDNF (p=0.001) and tyrosine kinase A (p=0.002) was also increased, as were cell bodies of the submucosal ganglia immunoreactive to CGRP (p=0.0009). INTERPRETATION: Faecal urgency and rectal hypersensitivity could result from increased numbers of polymodal sensory nerve fibres expressing TRPV1. The triggering factor or factors remain uncertain, but drugs that target nerve terminals that express this receptor, such as topical resiniferatoxin, deserve consideration.


Asunto(s)
Vías Aferentes/química , Proteínas de Transporte de Catión , Incontinencia Fecal/etiología , Incontinencia Fecal/patología , Hiperestesia/etiología , Hiperestesia/patología , Canales Iónicos , Glicoproteínas de Membrana , Fibras Nerviosas Amielínicas/química , Receptores de Droga/análisis , Enfermedades del Recto/etiología , Enfermedades del Recto/patología , Adulto , Biopsia , Temperatura Corporal , Estudios de Casos y Controles , Femenino , Factor Neurotrófico Derivado de la Línea Celular Glial , Proteína Ácida Fibrilar de la Glía/análisis , Humanos , Inmunohistoquímica , Proteínas de Filamentos Intermediarios/análisis , Masculino , Persona de Mediana Edad , Factor de Crecimiento Nervioso/análisis , Factores de Crecimiento Nervioso/análisis , Proteínas del Tejido Nervioso/análisis , Periferinas , Factores Desencadenantes , Proteínas Tirosina Quinasas Receptoras/análisis , Receptores de Péptido Relacionado con el Gen de Calcitonina/análisis , Receptores de Droga/inmunología , Proteínas S100/análisis , Umbral Sensorial , Sustancia P/análisis , Canales Catiónicos TRPV
19.
Br J Anaesth ; 89(6): 882-7, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12453933

RESUMEN

BACKGROUND: Anandamide, an endogenous lipid, activates both cannabinoid (CB(1)) and vanilloid (VR1) receptors, both of which are co-expressed in rat dorsal root ganglion (DRG) cells. Activation of either receptor results in analgesia but the relative contribution of CB(1) and VR1 in anandamide-induced analgesia remains controversial. Here we compare the in vitro pharmacology of recombinant and endogenous VR1 receptors using calcium imaging, in clonal and DRG cells, respectively. We also consider the contribution of CB(1) and VR1 receptors to anandamide-induced analgesia. METHODS: Using a Flurometric Imaging Plate Reader (FLIPR), calcium imaging has been used to study the effects of several vanilloid and cannabinoid ligands in rat VR1-transfected HEK293 (rVR1-HEK) cells and in DRG cells. The effect of pre-exposure of several vanilloid and cannabinoids has also been compared in DRG cells. RESULTS: The VR1 agonists capsaicin, olvanil, (N-(4-hydroxyphenyl-arachinoylamide) (AM404) and anandamide caused a concentration-dependent increase in intracellular calcium concentration ([Ca(2+)](i)), with similar temporal profiles in both rVR1-HEK and DRG cells, and potency (pEC(50)) values of 8.25 (SEM 0.11), 8.37 (0.04), 6.96 (0.06), 5.85 (0.01) and 7.45 (0.10), 7.55 (0.07), 6.10 (0.13), approximately 5.5, respectively. These responses were inhibited by the VR1 antagonist capsazepine (1 micro M). In contrast, application of synthetic cannabinoid antagonists failed to inhibit the anandamide-induced increase in [Ca(2+)](i). Reapplication of VR1 agonists significantly inhibited a subsequent challenge to either capsaicin or anandamide in either cell type, whilst pre-exposure to cannabinoid agonists were without effect. CONCLUSION: Here we provide evidence that the pharmacology of recombinant rVR1 receptors is similar to those endogenously expressed in DRG cells. Moreover, we have shown that VR1, but not CB(1), receptors are involved in anandamide-induced responses in dorsal root primary neurones in vitro. Therefore, the analgesic properties of anandamide are likely to be mediated, at least in part, by VR1 activation in DRG cells in vivo.


Asunto(s)
Ácidos Araquidónicos/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Capsaicina/análogos & derivados , Ganglios Espinales/efectos de los fármacos , Receptores de Droga/efectos de los fármacos , Animales , Calcio/análisis , Capsaicina/farmacología , Células Cultivadas/efectos de los fármacos , Células Clonales , Endocannabinoides , Ganglios Espinales/citología , Alcamidas Poliinsaturadas , Ratas , Receptores de Cannabinoides , Receptores de Droga/agonistas , Receptores de Droga/antagonistas & inhibidores
20.
Neuropharmacology ; 42(7): 873-88, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12069898

RESUMEN

The emergence of the TRP (C) and vanilloid (TRPV) receptor family of Ca(2+) permeable channels has started to provide molecular focus to a linked group of ion channels whose common feature is activation primarily by intracellular ligands. These channels have a central role in Ca(2+) homeostasis in virtually all cells and in particular those that lack voltage-gated Ca(2+) channels. We will discuss recent work that is more precisely defining both molecular form and physiological function of this important group of Ca(2+) permeable channels with particular focus on the intracellular ligands that gate and modulate channel activity.


Asunto(s)
Canales de Calcio/fisiología , Activación del Canal Iónico/fisiología , Lípidos/fisiología , Receptores de Droga/fisiología , Animales , Canales de Calcio/genética , Humanos , Receptores de Droga/genética , Canales Catiónicos TRPC , Transcripción Genética
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