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1.
Neuroimage ; 232: 117874, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609667

RESUMEN

Slot machines are a popular form of gambling, offering a tractable way to experimentally model reward processes. This study used a 3-reel slot paradigm to assess psychologically distinct phases of reward processing, reflecting anticipation, and early- and late-stage outcome processing. EEG measures of winning, nearly missing (a losing outcome revealed at the final, third reel), and "totally" missing (a losing outcome revealed earlier, at the second reel) were collected from healthy adults (n=54). Condition effects were evaluated in: i) event-related potential (ERP) components reflecting anticipatory attention (stimulus preceding negativity, SPN) and outcome processing (reward positivity, RewP and late-positive potential, LPP) and ii) total power and phase synchrony of theta and delta band oscillations. Behaviorally, trial initiation was fastest after a near miss outcome and slowest after a winning outcome. As expected, a significant SPN was observed for possible wins (AA) vs. total misses (AB), consistent with reward anticipation. Larger win (AAA) vs. near miss (AAB) amplitudes were observed for the RewP; LPP amplitudes were largest for wins (AAA), intermediate for near misses (AAB), and smallest for total misses (ABC), reflecting significant early (RewP) and late-stage (LPP) outcome processing effects. There was an effect of reel position on the RewP, with larger amplitude in the final reel (AAA-AAB) relative to the 2nd-reel locked difference waves (AA-AB). Across all outcomes, near misses elicited the largest and most phase-synchronized theta responses, while wins elicited larger and more phase-synchronized delta responses than total misses, with delta band measures not distinguishing between near misses and wins. . Phase locking measures contrasting win vs. near miss delta and theta synchronization, within time windows corresponding to ERP measurements, covaried with RewP, but not SPN or LPP, amplitude. Lastly, EEG measures showed differential relationships with age and self-reported consummatory pleasure. In the context of slot machine play, where reward anticipation and attainment place minimal demands on effort and skill, ERP and time-frequency methods capture distinct neurophysiological signatures of reward anticipation and outcome processing.


Asunto(s)
Anticipación Psicológica/fisiología , Electroencefalografía/métodos , Juego de Azar/fisiopatología , Tiempo de Reacción/fisiología , Recompensa , Percepción del Tiempo/fisiología , Adulto , Femenino , Juego de Azar/psicología , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
2.
Psychol Med ; 48(15): 2492-2499, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29444726

RESUMEN

BACKGROUND: Schizophrenia (SZ) is a severe neuropsychiatric disorder associated with disrupted connectivity within the thalamic-cortico-cerebellar network. Resting-state functional connectivity studies have reported thalamic hypoconnectivity with the cerebellum and prefrontal cortex as well as thalamic hyperconnectivity with sensory cortical regions in SZ patients compared with healthy comparison participants (HCs). However, fundamental questions remain regarding the clinical significance of these connectivity abnormalities. METHOD: Resting state seed-based functional connectivity was used to investigate thalamus to whole brain connectivity using multi-site data including 183 SZ patients and 178 matched HCs. Statistical significance was based on a voxel-level FWE-corrected height threshold of p < 0.001. The relationships between positive and negative symptoms of SZ and regions of the brain demonstrating group differences in thalamic connectivity were examined. RESULTS: HC and SZ participants both demonstrated widespread positive connectivity between the thalamus and cortical regions. Compared with HCs, SZ patients had reduced thalamic connectivity with bilateral cerebellum and anterior cingulate cortex. In contrast, SZ patients had greater thalamic connectivity with multiple sensory-motor regions, including bilateral pre- and post-central gyrus, middle/inferior occipital gyrus, and middle/superior temporal gyrus. Thalamus to middle temporal gyrus connectivity was positively correlated with hallucinations and delusions, while thalamus to cerebellar connectivity was negatively correlated with delusions and bizarre behavior. CONCLUSIONS: Thalamic hyperconnectivity with sensory regions and hypoconnectivity with cerebellar regions in combination with their relationship to clinical features of SZ suggest that thalamic dysconnectivity may be a core neurobiological feature of SZ that underpins positive symptoms.


Asunto(s)
Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Conectoma/métodos , Red Nerviosa/fisiopatología , Esquizofrenia/fisiopatología , Tálamo/fisiopatología , Adulto , Cerebelo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagen , Tálamo/diagnóstico por imagen
3.
Psychol Med ; 46(2): 367-79, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26415671

RESUMEN

BACKGROUND: Obsessive-compulsive disorder (OCD) is associated with an abnormally large error-related negativity (ERN), an electrophysiological measure of error monitoring in response to performance errors, but it is unclear if hoarding disorder (HD) also shows this abnormality. This study aimed to determine whether the neurophysiological mechanisms underlying error monitoring are similarly compromised in HD and OCD. METHOD: We used a visual flanker task to assess ERN in response to performance errors in 14 individuals with HD, 27 with OCD, 10 with HD+OCD, and 45 healthy controls (HC). Age-corrected performance and ERN amplitudes were examined using analyses of variance and planned pairwise group comparisons. RESULTS: A main effect of hoarding on ERN (p = 0.031) was observed, indicating ERN amplitudes were attenuated in HD relative to non-HD subjects. A group × age interaction effect on ERN was also evident. In HD-positive subjects, ERN amplitude deficits were significantly greater in younger individuals (r = -0.479, p = 0.018), whereas there were no significant ERN changes with increasing age in OCD and HC participants. CONCLUSIONS: The reduced ERN in HD relative to OCD and HC provides evidence that HD is neurobiologically distinct from OCD, and suggests that deficient error monitoring may be a core pathophysiological feature of HD. This effect was particularly prominent in younger HD participants, further suggesting that deficient error monitoring manifests most strongly early in the illness course and/or in individuals with a relatively early illness onset.


Asunto(s)
Encéfalo/fisiopatología , Trastorno de Acumulación/fisiopatología , Trastorno Obsesivo Compulsivo/fisiopatología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis y Desempeño de Tareas , Adulto Joven
4.
Arch Gynecol Obstet ; 294(1): 161-4, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26676831

RESUMEN

BACKGROUND: HBA1c is used as an indicator for the long-term control of the glycaemic state and outcome predictors in diabetic patients. Diabetic patients have an increased risk of post-operative complications especially those related to infection. The aim of our study is to ascertain the relationship between HBA1c levels and post-operative recovery within the subspecialty of gynaecological oncology. METHOD: Prospective cohort study during the period 1 August 2012 through 31 August 2014. Preoperative measurement of HBA1c on all gynaecological oncology patients that underwent major surgery. Patient variables collected and analysed were BMI (kg/m(2)), length of stay (LOS in days), cancer stage (stage 1 through stage 4), infective complications, non-infective complications and readmission to hospital. RESULTS: A total of 300 patients were included in our study, 34 of them were known to be diabetic while 266 were presumed to be non-diabetic. Of the presumed non-diabetic cohort, 17.3 % (46/266) had impaired glucose tolerance or diabetes. Mean BMI was significantly increased in the pre-existing diabetic group (32.8 vs. 29.3 kg/m(2), p = 0.016). Infective complications were almost double the rate amongst the known diabetic women than those presumed to be non-diabetic (32.4 vs. 18.0 %, p = 0.048). Rate of re-admission to hospital due to complications was 20.6 % in the diabetic group and 4.1 % within the presumed non-diabetic group (p < 0.001). Infective complications occurred in 16.9 % of women with HBA1c <42 mmol/mol, 22.7 % of those with HBA1c of 42-47 mmol/mol, 43.5 % of patients with HBA1c 48-64 mmol/mol and 37.5 % of patients with HBA1c >64 mmol/mol. Non-infective complications were also more frequent in women with elevated HBA1c (11.1, 22.7, 26.1 and 12.5 % in those women with HBA1c <42, 42-47, 48-64 and >64 mmol/mol, respectively). Re-admission to hospital within 30 days for a complication of surgery occurred in 4.4 % of women with HBA1c <42 mmol/mol, 4.5 % of women with HBA1c measured at 42-47 mmol/mol, 30.8 % of those with HBA1c 48-64 mmol/mol and 25 % of women with HBA1c >64 mmol/mol. CONCLUSION: Preoperative measurement of HBA1c may identify patients (both diabetic and non-diabetic women) at higher risk of postoperative complications and could be used as a trigger for modification of the perioperative management of such patients.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus/sangre , Neoplasias de los Genitales Femeninos/cirugía , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Complicaciones Posoperatorias/epidemiología , Cuidados Preoperatorios , Glucemia/análisis , Femenino , Intolerancia a la Glucosa , Hemoglobina Glucada/análisis , Humanos , Infecciones/epidemiología , Infecciones/etiología , Tiempo de Internación , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Periodo Preoperatorio , Pronóstico , Estudios Prospectivos , Riesgo
5.
Arch Gynecol Obstet ; 291(3): 653-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25260989

RESUMEN

BACKGROUND/AIM: According to recent studies up to 80% of patients would like to receive more information about how cancer treatments can affect their sexual functioning. Moreover, 75 % of them would not feel comfortable being the first to bring up the subject. Our Gynaecological Advice Clinic was established in 2006 at the Christie Hospital and offers support to cancer patients who face sexuality issues. A previous evaluation established that the service sees approximately, 200 patients per year. The aims of this study are to evaluate the service by collecting data relating to levels of attendance, type and amount of clinical activity and to explore further patients' experiences and management. METHODS: This is a retrospective study which was carried out in 2012-2013. Different models are used to evaluate our patients including history taking integrated therapy model, consultations to understand the normal anatomy and physiology with the use of diagrams and photographs, psycho-education and the international classification "Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition" (DSMV). The treatment options advised include medications such as hormone replacement treatment, testosterone, antidepressant, local oestrogen, tibolone, aqueous cream, lubrication to introitus, diprobase, dermal cream and advice for massage to areas of discomfort. Moreover, the use of vaginal dilators, the role of pelvic floor exercises, vulval care and self examination are explained. The team works closely with the psycho-oncology department. The most frequently discussed topics that were covered during the consultation are analysed. RESULTS: 41 outpatient clinics were held between 2012 and 2013. 194 patients attended those clinics during the study period. Single and not group therapy was offered to all the participants. 216 patients were offered appointments while 194 patients actually attended (90%). Patients' age ranged from 24 to 91 years with a mean age of 59 years. 45% had endometrial and 32% cervical cancer, 18% vulval cancer, 4 % ovarian cancer. 74% attended on their own while 18% with their partners and 8% with another family member or friend. 98% of the patients had confidence/trust in the healthcare professional. 95% felt involved with treatment decisions. 82% reported completely understanding information about side-effects. 16% were unaware of who to contact once they had completed treatment. 8% were attending for on-going help with psycho-sexual concerns following completion of treatment. CONCLUSION: The clinic was positively evaluated by patients, they had a high level of trust in the nurses running the service and they found it beneficial. Consultations were generally lasting 20-30 min and most patients reported this was an appropriate length. It once again highlights that although the service was set-up to address psycho-sexual concerns, in reality it dealt with a variety of other patient concerns. Due to the success of the clinic, the service has expanded and we are now supporting patients from other tumour groups such as colorectal, urology and plastic surgery.


Asunto(s)
Neoplasias de los Genitales Femeninos/terapia , Servicios de Salud/estadística & datos numéricos , Relaciones Enfermero-Paciente , Derivación y Consulta/estadística & datos numéricos , Conducta Sexual , Sexualidad/psicología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Personal de Salud , Servicios de Salud/normas , Humanos , Persona de Mediana Edad , Enfermeras y Enfermeros , Estudios Retrospectivos , Sexualidad/fisiología , Encuestas y Cuestionarios
6.
Suppl Clin Neurophysiol ; 62: 163-80, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24053039

RESUMEN

BACKGROUND: In electroencephalogram (EEG) studies of auditory steady-state responses (ASSRs), patients with schizophrenia show a deficit in power and/or phase-locking, particularly at the 40 Hz frequency where these responses resonate. In addition, studies of the transient gamma-band response (GBR) elicited by single tones have revealed deficits in gamma power and phase-locking in schizophrenia. We examined the degree to which the 40 Hz ASSR and the transient GBR to single tones are correlated and whether they assess overlapping or distinct gamma-band abnormalities in schizophrenia. METHODS: EEG was recorded during 40 Hz ASSR and auditory oddball paradigms from 28 patients with schizophrenia or schizoaffective disorder (SZ) and 25 age- and gender-matched healthy controls (HC). The ASSR was elicited by 500 ms click trains, and the transient GBR was elicited by the standard tones from the oddball paradigm. Gamma phase and magnitude values, calculated using Morlet wavelet transformations, were used to derive total power and phase-locking measures. RESULTS: Relative to HC, SZ patients had significant deficits in total gamma power and phase-locking for both ASSR- and GBR-based measures. Within both groups, the 40 Hz ASSR and GBR phase-locking measures were significantly correlated, with a similar trend evident for the total power measures. Moreover, co-varying for GBR substantially reduced 40 Hz ASSR power and phase-locking differences between the groups. CONCLUSIONS: 40 Hz ASSR and transient GBR measures provide very similar information about auditory gamma abnormalities in schizophrenia, despite the overall enhancement of 40 Hz ASSR total power and phase-locking values relative to the corresponding GBR values.


Asunto(s)
Trastornos de la Percepción Auditiva/etiología , Mapeo Encefálico , Ondas Encefálicas/fisiología , Potenciales Evocados Auditivos/fisiología , Esquizofrenia/complicaciones , Estimulación Acústica , Adulto , Análisis de Varianza , Estudios de Casos y Controles , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Psicoacústica , Tiempo de Reacción , Esquizofrenia/diagnóstico , Factores de Tiempo , Adulto Joven
8.
Brain Stimul ; 15(1): 63-72, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34767967

RESUMEN

BACKGROUND: The efficacy of repetitive transcranial magnetic stimulation (rTMS) for depression may vary depending on the subregion stimulated within the dorsolateral prefrontal cortex (DLPFC). Clinical TMS typically uses scalp-based landmarks for DLPFC targeting, rather than individualized MRI guidance. OBJECTIVE: In rTMS patients, determine the brain systems targeted by multiple DLPFC stimulation rules by computing several surrogate measures: underlying brain targets labeled with connectivity-based atlases, subgenual cingulate anticorrelation strength, and functionally connected networks. METHODS: Forty-nine patients in a randomized controlled trial of rTMS therapy for treatment resistant major depression underwent structural and functional MRI. DLPFC rules were applied virtually using MR-image guidance. Underlying cortical regions were labeled, and connectivity with the subgenual cingulate and whole-brain computed. RESULTS: Scalp-targeting rules applied post hoc to these MRIs that adjusted for head size, including Beam F3, were comparably precise, successful in directly targeting classical DLPFC and frontal networks, and anticorrelated with the subgenual cingulate. In contrast, all rules involving fixed distances introduced variability in regions and networks targeted. The 5 cm rule targeted a transitional DLPFC region with a different connectivity profile from the adjusted rules. Seed-based connectivity analyses identified multiple regions, such as posterior cingulate and inferior parietal lobe, that warrant further study in order to understand their potential contribution to clinical response. CONCLUSION: EEG-based rules consistently targeted DLPFC brain regions with resting-state fMRI features known to be associated with depression response. These results provide a bridge from lab to clinic by enabling clinicians to relate scalp-targeting rules to functionally connected brain systems.


Asunto(s)
Trastorno Depresivo Resistente al Tratamiento , Estimulación Magnética Transcraneal , Depresión/diagnóstico por imagen , Depresión/terapia , Trastorno Depresivo Resistente al Tratamiento/diagnóstico por imagen , Trastorno Depresivo Resistente al Tratamiento/terapia , Humanos , Imagen por Resonancia Magnética , Corteza Prefrontal/fisiología , Estimulación Magnética Transcraneal/métodos
9.
Psychol Med ; 41(5): 959-69, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20663254

RESUMEN

BACKGROUND: Patients with schizophrenia (SZ) characteristically exhibit supranormal levels of cortical activity to self-induced sensory stimuli, ostensibly because of abnormalities in the neural signals (corollary discharges, CDs) normatively involved in suppressing the sensory consequences of self-generated actions. The nature of these abnormalities is unknown. This study investigated whether SZ patients experience CDs that are abnormally delayed in their arrival at the sensory cortex. METHOD: Twenty-one patients with SZ and 25 matched control participants underwent electroencephalography (EEG). Participants' level of cortical suppression was calculated as the amplitude of the N1 component evoked by a button press-elicited auditory stimulus, subtracted from the N1 amplitude evoked by the same stimulus presented passively. In the three experimental conditions, the auditory stimulus was delivered 0, 50 or 100 ms subsequent to the button-press. Fifteen SZ patients and 17 healthy controls (HCs) also underwent diffusion tensor imaging (DTI), and the fractional anisotropy (FA) of participants' arcuate fasciculus was used to predict their level of cortical suppression in the three conditions. RESULTS: While the SZ patients exhibited subnormal N1 suppression to undelayed, self-generated auditory stimuli, these deficits were eliminated by imposing a 50-ms, but not a 100-ms, delay between the button-press and the evoked stimulus. Furthermore, the extent to which the 50-ms delay normalized a patient's level of N1 suppression was linearly related to the FA of their arcuate fasciculus. CONCLUSIONS: These data suggest that SZ patients experience temporally delayed CDs to self-generated auditory stimuli, putatively because of structural damage to the white-matter (WM) fasciculus connecting the sites of discharge initiation and destination.


Asunto(s)
Imagen de Difusión Tensora , Electroencefalografía , Retroalimentación Sensorial , Alucinaciones/fisiopatología , Vías Nerviosas , Esquizofrenia/fisiopatología , Adulto , Anciano , Corteza Auditiva/fisiopatología , Estudios de Casos y Controles , Femenino , Lóbulo Frontal/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Modelos Neurológicos , Inhibición Neural , Percepción del Habla
10.
Brain Stimul ; 14(3): 703-709, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33866020

RESUMEN

BACKGROUND: Precise targeting of brain functional networks is believed critical for treatment efficacy of rTMS (repetitive pulse transcranial magnetic stimulation) in treatment resistant major depression. OBJECTIVE: To use imaging data from a "failed" clinical trial of rTMS in Veterans to test whether treatment response was associated with rTMS coil location in active but not sham stimulation, and compare fMRI functional connectivity between those stimulation locations. METHODS: An imaging substudy of 49 Veterans (mean age, 56 years; range, 27-78 years; 39 male) from a randomized, sham-controlled, double-blinded clinical trial of rTMS treatment, grouping participants by clinical response, followed by group comparisons of treatment locations identified by individualized fiducial markers on structural MRI and resting state fMRI derived networks. RESULTS: The average stimulation location for responders versus nonresponders differed in the active but not in the sham condition (P = .02). The average responder location derived from the active condition showed significant negative functional connectivity with the subgenual cingulate (P < .001) while the nonresponder location did not (P = .17), a finding replicated in independent cohorts of 84 depressed and 35 neurotypical participants. The responder and nonresponder stimulation locations evoked different seed based networks (FDR corrected clusters, all P < .03), revealing additional brain regions related to rTMS treatment outcome. CONCLUSION: These results provide evidence from a randomized controlled trial that clinical response to rTMS is related to accuracy in targeting the region within DLPFC that is negatively correlated with subgenual cingulate. These results support the validity of a neuro-functionally informed rTMS therapy target in Veterans.


Asunto(s)
Trastorno Depresivo Resistente al Tratamiento , Estimulación Magnética Transcraneal , Encéfalo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Prefrontal , Resultado del Tratamiento
11.
J Obstet Gynaecol ; 30(3): 226-30, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20373919

RESUMEN

Vulvovaginal-gingival syndrome is a distinct variant of classic lichen planus frequently associated with mucocutaneous scarring and vaginal stricture formation, therefore early diagnosis and treatment through a multidisciplinary approach is essential. Management is challenging and is characterised by wide variation in treatments and lack of evidence-based therapeutic approaches. Literature review with particular regard to therapeutic approaches is performed with a view towards a cooperative treatment study.


Asunto(s)
Liquen Plano/complicaciones , Vaginitis/complicaciones , Vulvitis/complicaciones , Femenino , Glucocorticoides/uso terapéutico , Hematocolpos/complicaciones , Humanos , Inmunosupresores/uso terapéutico , Liquen Plano/tratamiento farmacológico , Liquen Plano Oral , Imagen por Resonancia Magnética , Persona de Mediana Edad , Grupo de Atención al Paciente , Síndrome , Resultado del Tratamiento , Vaginitis/tratamiento farmacológico , Vaginitis/patología , Vulvitis/tratamiento farmacológico , Vulvitis/patología
12.
Schizophr Bull ; 35(1): 47-57, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18990710

RESUMEN

INTRODUCTION: Auditory hallucinations are a hallmark symptom of schizophrenia. The neural basis of auditory hallucinations was examined using data from a working memory task. Data were acquired within a multisite consortium and this unique dataset provided the opportunity to analyze data from a large number of subjects who had been tested on the same procedures across sites. We hypothesized that regions involved in verbal working memory and language processing would show activity that was associated with levels of hallucinations during a condition where subjects were rehearsing the stimuli. METHODS: Data from the Sternberg Item Recognition Paradigm, a working memory task, were acquired during functional magnetic resonance imaging procedures. The data were collected and preprocessed by the functional imaging biomedical informatics research network consortium. Schizophrenic subjects were split into nonhallucinating and hallucinating subgroups and activity during the probe condition (in which subjects rehearsed stimuli) was examined. Levels of activation from contrast images for the probe phase (collapsed over levels of memory load) of the working memory task were also correlated with levels of auditory hallucinations from the Scale for the Assessment of Positive Symptoms scores. RESULTS: Patients with auditory hallucinations (relative to nonhallucinating subjects) showed decreased activity during the probe condition in verbal working memory/language processing regions, including the superior temporal and inferior parietal regions. These regions also showed associations between activity and levels of hallucinations in a correlation analysis. DISCUSSION: The association between activation and hallucinations scores in the left hemisphere language/working memory regions replicates the findings of previous studies and provides converging evidence for the association between superior temporal abnormalities and auditory hallucinations.


Asunto(s)
Alucinaciones/diagnóstico , Alucinaciones/fisiopatología , Imagen por Resonancia Magnética , Memoria a Corto Plazo , Lóbulo Parietal/fisiopatología , Lóbulo Temporal/fisiopatología , Adolescente , Adulto , Anciano , Femenino , Lateralidad Funcional/fisiología , Alucinaciones/etiología , Humanos , Masculino , Persona de Mediana Edad , Reconocimiento en Psicología , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatología , Índice de Severidad de la Enfermedad , Conducta Verbal , Adulto Joven
13.
Neurotoxicology ; 56: 196-203, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27527991

RESUMEN

Exposure to organophosphates (OPs) often results in seizures and/or status epilepticus (SE) that produce neural damage within the central nervous system (CNS). Early control of SE is imperative for minimizing seizure-related CNS neuropathology. Although standard therapies exist, more effective agents are needed to reduce OP-induced SE and neuronal loss, particularly therapies with efficacy when administered 10's of minutes after the onset of SE. To evaluate novel antiseizure compounds, animal models should simulate the CNS effects of OP exposure observed in humans. We characterized in rats the effects of the OP, diisopropyl flourophosphate (DFP) as a function of dose and route of administration of supporting agents (pyridostigmine, 2-PAM, atropine); outcome measures were mortality, electrographic seizure activity during SE, and subsequent CNS neuropathology. Doses of DFP between 3 and 7mg/kg consistently caused SE, and the latency to behavioral tremors and to subsequent initiation of SE were dose related. In distinction, all doses of DFP that resulted in electrographic SE (3-7mg/kg) produced seizures of similar intensity and duration, and similar CNS neuropathology (i.e., the effects were all-or-none). Although SE was similar across doses, mortality progressively increased with higher doses of DFP. Mortality was significantly lower when the route of administration of therapeutic agents was intramuscular compared to intraperitoneal. This rodent model of OP poisoning demonstrates pathological characteristics similar to those observed in humans, and thus begins to validate this model for investigating potential new therapeutic approaches.


Asunto(s)
Enfermedades del Sistema Nervioso Central/inducido químicamente , Organofosfatos/toxicidad , Hidrolasas de Triéster Fosfórico/toxicidad , Estado Epiléptico/inducido químicamente , Animales , Antídotos/farmacología , Atropina/farmacología , Enfermedades del Sistema Nervioso Central/tratamiento farmacológico , Enfermedades del Sistema Nervioso Central/mortalidad , Inhibidores de la Colinesterasa/uso terapéutico , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Electroencefalografía , Masculino , Compuestos de Pralidoxima/farmacología , Bromuro de Piridostigmina/uso terapéutico , Ratas , Ratas Sprague-Dawley , Estado Epiléptico/tratamiento farmacológico , Estado Epiléptico/mortalidad
14.
AJNR Am J Neuroradiol ; 37(6): 1132-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27056428

RESUMEN

BACKGROUND AND PURPOSE: The importance of collateralization for maintaining adequate cerebral perfusion is increasingly recognized. However, measuring collateral flow noninvasively has proved elusive. The aim of this study was to assess correlations among baseline perfusion and arterial transit time artifacts, cerebrovascular reactivity, and the presence of collateral vessels on digital subtraction angiography. MATERIALS AND METHODS: The relationship between the presence of collateral vessels on arterial spin-labeling MR imaging and DSA was compared with blood oxygen level-dependent MR imaging measures of hypercapnic cerebrovascular reactivity in patients with symptomatic intracranial stenosis (n = 18). DSA maps were reviewed by a neuroradiologist and assigned the following scores: 1, collaterals to the periphery of the ischemic site; 2, complete irrigation of the ischemic bed via collateral flow; and 3, normal antegrade flow. Arterial spin-labeling maps were scored according to the following: 0, low signal; 1, moderate signal with arterial transit artifacts; 2, high signal with arterial transit artifacts; and 3, normal signal. RESULTS: In regions with normal-to-high signal on arterial spin-labeling, collateral vessel presence on DSA strongly correlated with declines in cerebrovascular reactivity (as measured on blood oxygen level-dependent MR imaging, P < .001), most notably in patients with nonatherosclerotic disease. There was a trend toward increasing cerebrovascular reactivity with increases in the degree of collateralization on DSA (P = .082). CONCLUSIONS: Collateral vessels may have fundamentally different vasoreactivity properties from healthy vessels, a finding that is observed most prominently in nonatherosclerotic disease and, to a lesser extent, in atherosclerotic disease.


Asunto(s)
Angiografía de Substracción Digital , Trastornos Cerebrovasculares/diagnóstico por imagen , Circulación Colateral , Imagen Multimodal/métodos , Adulto , Anciano , Circulación Cerebrovascular , Constricción Patológica/diagnóstico por imagen , Femenino , Hemodinámica , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad
15.
Clin Oncol (R Coll Radiol) ; 28(12): 760-765, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27401967

RESUMEN

AIMS: Ovarian cancer is the principal cause of gynaecological cancer death in developed countries, yet overall survival in the UK has been reported as being inferior to that in some Western countries. As there is a range of survival across the UK we hypothesised that in major regional centres, outcomes are equivalent to the best internationally. MATERIALS AND METHODS: Data from patients treated in multicentre international and UK-based trials were obtained from three regional cancer centres in the UK; Manchester, University College London and Leeds (MUL). The median progression-free survival (PFS) and overall survival were calculated for each trial and compared with the published trial data. Normalised median survival values and the respective 95% confidence intervals (ratio of pooled MUL data to trial median survival) were calculated to allow inter-trial survival comparisons. This strategy then allowed a comparison of median survival across the UK, in three regional UK centres and in international centres. RESULTS: The analysis showed that the trial-reported PFS was the same in the UK, in the MUL centres and in international centres for each of the trials included in the study. Overall survival was, however, 45% better in major regional centre-treated patients (95% confidence interval 9-73%) than the median overall survival reported in UK trials, whereas the median overall survival in MUL centres equated with that achieved in international centres. CONCLUSION: The data suggest that international survival statistics are achieved in UK regional cancer centres.


Asunto(s)
Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/terapia , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad
16.
Case Rep Obstet Gynecol ; 2015: 919584, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26257971

RESUMEN

Introduction. Primary malignant melanoma of the urethra is a rare tumour (0.2% of all melanomas) that most commonly affects the meatus and distal urethra and is three times more common in women than men. Case. A 76-year-old lady presented with vaginal pain and discharge. On examination, a 4 cm mass was noted in the vagina and biopsy confirmed melanoma of a balloon type. Preoperative CT showed no distant metastases and an MRI scan of the pelvis demonstrated no associated lymphadenopathy. She underwent anterior exenterative surgery and vaginectomy also. Histology confirmed a urethral nodular malignant melanoma. Discussion. First-line treatment of melanoma is often surgical. Adjuvant treatment including chemotherapy, radiotherapy, or immunotherapy has also been reported. Even with aggressive management, malignant melanoma of the urogenital tract generally has a poor prognosis. Recurrence rates are high and the mean period between diagnosis and recurrence is 12.5 months. A 5-year survival rate of less than 20% has been reported in balloon cell melanomas along with nearly 20% developing local recurrence. Conclusion. To the best of our knowledge, this case is the first report of balloon cell melanoma arising in the urethra. The presentation and surgical management has been described and a literature review provided.

17.
Br J Pharmacol ; 63(3): 561-6, 1978 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-667500

RESUMEN

1 The binding of [3H]-5-hydroxytryptamine ([3H]-5-HT), [3H]-haloperidol and [3H]-dopamine to human blood platelets was investigated and the effects of unlabelled haloperidol on [3H]-5-HT binding and (+)- and (-)-butaclamol on [3H]-haloperidol were studied. 2 Scatchard analysis did not show any specific binding of [3H]-haloperidol or [3H]-dopamine to platelets, but two binding sites were identified for binding of [3H]-5-HT. 3 Unlabelled haloperidol reduced the binding of 5-HT in concentrations comparable to those inhibigint 5-HT-induced platelet aggregation; (+)- and (-)-butaclamol did not affect the binding of [3H]-haloperidol. 4 It is concluded that haloperidol binding represents saturation of the platelet membrane, and that the platelet is not a suitable model for investigation of dopamine-drug interactions.


Asunto(s)
Plaquetas/metabolismo , Dopamina/sangre , Haloperidol/sangre , Serotonina/sangre , Adulto , Unión Competitiva/efectos de los fármacos , Butaclamol/farmacología , Femenino , Humanos , Técnicas In Vitro , Masculino , Factores de Tiempo
18.
J Telemed Telecare ; 6 Suppl 2: S41-3, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10975097

RESUMEN

The effect of health education programmes depends on the number of people exposed to the messages, as well as the method and style in which the information is transmitted. We conducted a pilot project to encourage healthier lifestyles by presenting culturally sensitive information using a variety of media. Material intended to provoke discussion was shared with a range of audiences in Barbados and Montserrat in the West Indies by a series of lecture discussions, which were videorecorded for local television and sound recorded for local radio. The lecture was also disseminated by newspaper articles, a special magazine and by publication on the Internet. The aim of the project was to achieve maximum effect for minimum effort, thus making optimum use of resources. The feedback obtained at the lecture discussions and in response to the radio broadcasts and newspaper articles provided a needs assessment on which to base a definitive programme, and confirmed that radio and television are the most effective media for health education.


Asunto(s)
Educación en Salud/economía , Medios de Comunicación de Masas , Multimedia , Barbados , Educación en Salud/métodos , Humanos , Evaluación de Necesidades , Proyectos Piloto
20.
Neuroscience ; 231: 145-56, 2013 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-23159312

RESUMEN

Better treatment of status epilepticus (SE), which typically becomes refractory after about 30 min, will require new pharmacotherapies. The effect of sec-butyl-propylacetamide (SPD), an amide derivative of valproic acid (VPA), on electrographic status epilepticus (ESE) was compared quantitatively to other standard-of-care compounds. Cortical electroencephalograms (EEGs) were recorded from rats during ESE induced with lithium-pilocarpine. Using a previously-published algorithm, the effects of SPD on ESE were compared quantitatively to other relevant compounds. To confirm benzodiazepine resistance, diazepam (DZP) was shown to suppress ESE when administered 15 min after the first motor seizure, but not after 30 min (100mg/kg). VPA (300 mg/kg) also lacked efficacy at 30 min. SPD (130 mg/kg) strongly suppressed ESE at 30 min, less after 45 min, and not at 60 min. At a higher dose (180 mg/kg), SPD profoundly suppressed ESE at 60 min, similar to propofol (100mg/kg) and pentobarbital (30 mg/kg). After 4-6h of SPD-induced suppression, EEG activity often overshot control levels at 7-12h. Valnoctamide (VCD, 180 mg/kg), an SPD homolog, was also efficacious at 30 min. SPD blocks pilocarpine-induced electrographic seizures when administered at 1h after the first motor seizure. SPD has a faster onset and greater efficacy than DZP and VPA, and is similar to propofol and pentobarbital. SPD and structurally similar compounds may be useful for the treatment of refractory ESE. Further development and use of automated analyses of ESE may facilitate drug discovery for refractory SE.


Asunto(s)
Amidas/uso terapéutico , Anticonvulsivantes/uso terapéutico , Corteza Cerebral/efectos de los fármacos , Estado Epiléptico/tratamiento farmacológico , Ácido Valproico/análogos & derivados , Amidas/farmacología , Animales , Anticonvulsivantes/farmacología , Corteza Cerebral/fisiopatología , Diazepam/farmacología , Diazepam/uso terapéutico , Relación Dosis-Respuesta a Droga , Electroencefalografía , Masculino , Pentobarbital/farmacología , Pentobarbital/uso terapéutico , Pilocarpina , Ratas , Ratas Sprague-Dawley , Estado Epiléptico/inducido químicamente , Estado Epiléptico/fisiopatología , Ácido Valproico/farmacología , Ácido Valproico/uso terapéutico
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