Streptococcus cuniculi sp. nov., isolated from the respiratory tract of wild rabbits.

Biochemical and molecular genetic studies were performed on four unknown Gram-stain-positive, catalase-negative, coccus-shaped organisms isolated from tonsils (n = 3) and nasal samples (n = 1) of four wild rabbits. The micro-organism was identified as a streptococcal species based on its cellular morphological and biochemical tests. Comparative 16S rRNA gene sequencing confirmed its identification as a member of the genus Streptococcus, but the organism did not correspond to any recognized species of this genus. The closest phylogenetic relative of the unknown cocci from wild rabbits was Streptococcus acidominimus NCIMB 702025(T) (97.9% 16S rRNA gene sequence similarity). rpoB and sodA sequence analysis of the novel isolate showed interspecies divergence of 16.2% and 20.3%, respectively, from the type strain of its closest 16S rRNA gene phylogenetic relative, S. acidominimus. The novel bacterial isolate could be distinguished from the type strain of S. acidominimus by several biochemical characteristics, such as the production of esterase C4, acid phosphatase and naphthol-AS-BI-phosphohydrolase and acidification of different sugars. Based on both phenotypic and phylogenetic findings, it is proposed that the unknown bacterium be classified as a novel species of the genus Streptococcus, Streptococcus cuniculi sp. nov. The type strain is NED12-00049-6B(T) ( = CECT 8498(T) = CCUG 65085(T)).

[Cognitive profiles in pervasive developmental disorders]. / Les profils cognitifs dans les troubles envahissants du développement.

OBJECTIVE: This study investigated the cognitive skills in pervasive developmental disorders (PDD). METHODOLOGY: Two groups of children participated in this study, 39 individuals with autism and 18 individuals with Asperger syndrome. Each participant was assessed by the Wechsler scales: WPPSI-III, WISC-III or WISC-IV. RESULTS: Children with Asperger syndrome have VIQ more than PIQ and the children with autism have VIQ less than PIQ. The performances in "block design" task vary according to the cognitive level and not according to the PDD type. The high-functioning autistic children show high performance in "block design" task. Children with Asperger syndrome revealed impairments in the "understanding of social situations" task. DISCUSSION: Individuals with autism have a verbal intelligence quotient lower than individuals with an Asperger syndrome. Several hypotheses have tried to explain verbal differences between children with autism and Asperger syndrome. A first hypothesis proposed a developmental convergence between these two groups. A second hypothesis suggested that communication and social interaction impairments could be implicated in verbal skills. A third hypothesis supported that individuals with Asperger syndrome could develop a specific cognitive style. Children with autism have spatial and perceptive capacities better than verbal capacities. These performances could be interpreted as the expression of a specific cognitive style based on the visual analysis of the detail. CONCLUSION: The low-functioning children with autism have a cognitive profile with PIQ more than VIQ and high skills in spatial organization. The high-level children with autism have a cognitive profile with PIQ more than VIQ and high skills in spatial abstraction. Children with Asperger syndrome have a profile VIQ more than PIQ profile, they are particularly good in verbal learning notably vocabulary.

Stroke initial severity and outcome relative to insurance status in a universal health care system in Switzerland.

BACKGROUND: Socioeconomic status is thought to have a significant influence on stroke incidence, risk factors and outcome. Its influence on acute stroke severity, stroke mechanisms, and acute recanalisation treatment is less known. METHODS: Over a 4-year period, all ischaemic stroke patients admitted within 24h were entered prospectively in a stroke registry. Data included insurance status, demographics, risk factors, time to hospital arrival, initial stroke severity (NIHSS), etiology, use of acute treatments, short-term outcome (modified Rankin Scale, mRS). Private insured patients (PI) were compared with basic insured patients (BI). RESULTS: Of 1062 consecutive acute ischaemic stroke patients, 203 had PI and 859 had BI. They were 585 men and 477 women. Both populations were similar in age, cardiovascular risk factors and preventive medications. The onset to admission time, thrombolysis rate, and stroke etiology according to TOAST classification were not different between PI and BI. Mean NIHSS at admission was significantly higher for BI. Good outcome (mRS≤2) at 7days and 3months was more frequent in PI than in BI. CONCLUSION: We found better outcome and lesser stroke severity on admission in patients with higher socioeconomic status in an acute stroke population. The reason for milder strokes in patients with better socioeconomic status in a universal health care system needs to be explained.

[Multiple ischemic strokes due to Borrelia garinii meningovasculitis]. / Attaques cérébrovasculaires ischémiques multiples dues à une méningovasculite à Borrelia garinii.

The most frequent clinical manifestation of borreliosis in Switzerland is erythema migrans, with about 2500 patients each year. Neurological manifestations are rare, mostly hyperalgesic radiculitis (Bannwarth syndrome), aseptic meningitis or cranial nerve involvement. We report the first Swiss patient with meningovasculitis due to neuroborreliosis, with recurrent multiple ischemic strokes in multiple vascular territories. The treatment with ceftriaxone stopped the progression, but the patient is still suffering from severe invalidating cognitive disorders. We also comment on the pathophysiology and review the literature of other clinical cases.

Perfusion-CT imaging in epileptic seizures.

INTRODUCTION: PCT is used in the diagnosis of acute neurological syndromes, particularly stroke. We aimed to evaluate PCT abnormalities in patients with acute epileptic seizures or status epilepticus (SE). METHODS: We collected patients undergoing acute PCT for the suspicion of acute ischemic stroke (AIS), who received a final diagnosis of focal seizures or generalised seizures with a post-ictal deficit, with or without concomitant AIS. PCTs were retrospectively analysed for the presence of hyper- and hypoperfusion, and results correlated with delay from seizure onset, aetiology, type of seizures and the presence of electrical SE. RESULTS: Half of the 43 consecutively identified patients had regional PCT abnormalities-hyperperfusion in 13 (30%) and hypoperfusion in 8 (19%)-and 4 (9%) had AIS. Among patients with hyperperfusion, six (46%) had a focal deficit during imaging acquisition (two a normal clinical status, one altered consciousness and four ongoing seizure); nine (69%) of these patients had a SE; none had a stroke. All patients with hypoperfusion had focal neurological deficit; three (37%) of them a simultaneous ischemic stroke (in the remaining five, hypoperfusion was considered to be related to the seizure post-ictal phase). In the 22 with normal perfusion, 9 had a focal deficit (10 a normal clinical status, 2 altered consciousness and 1 ongoing seizure); 3 had a SE, and 1 had a stroke. Patients with SE featured a higher prevalence of hyperperfusion (9/13 [69%] vs. 4/30 [13%] without SE, p = 0.00). CONCLUSION: In patients with acute epileptic seizures, regional hyperperfusion on PCT may suggest an ongoing or recently resolved SE, whereas hypoperfusion may be due to post-ictal state or simultaneous AIS. These observations might help attributing focal deficits to epileptic seizures rather than stroke, allowing for targeted therapy.

Opposite effects of antimicrotubule agents on c-myc oncogene expression depending on the cell lines used.

We investigated the expression of c-myc in HT29-D4, HBL100 and Caco-2 cells treated with microtubule stabilising (paclitaxel) or depolymerising agents (vinblastine, nocodazole). After induction by epidermal growth factor (EGF), c-myc expression decreased in HT29-D4 cells treated with all the antimicrotubule agents. In HBL100 and Caco-2, when microtubules were stabilised with paclitaxel, c-myc expression also decreased. In contrast, its expression increased after treatment with depolymerising agents. In both cell lines, we also observed that depolymerising agents alone induced c-myc expression whilst paclitaxel had no effect. This mRNA induction was confirmed at the protein level. In HT29-D4, no variation of c-myc expression was observed. Then, we showed that the increase of mRNA level was due to activation of gene transcription. These results indicate that modulation of c-myc expression varied depending on the cell lines used and the type of antimicrotubule agents. This work provides a potential link between the microtubular network and c-myc gene expression.

Effects of glucocorticoids on hepatic sensitivity to insulin and glucagon in man.

AIMS: This study was undertaken to determine the effects of a short-term dexamethasone treatment on hepatic sensitivities to insulin and glucagon. METHODS: Eleven healthy subjects were studied during one or several of four protocols. In all protocols, somatostatin was infused continuously to inhibit pancreatic hormone secretion. In protocol 1, basal insulin was infused over 300 min while glucagon was infused at a rate of 0.5 mg/kg(-1)/min(-1)during 180 min, then at a rate of 1.5 ng/kg(-1)/min(-1)during 150 min. In protocol 2, the same experiment was performed after a 2 day treatment with 8 mg/day dexamethasone. In protocol 3, the two-step glucagon infusion was performed during insulin infusion at a rate aimed to reproduce the hyperinsulinemia observed during protocol 2. In protocol 4, continuous basal insulin and low glucagon (0.5 mg/kg(-1)/min(-1)) were infused over 330 min. RESULTS: In protocol 1, plasma glucose rose transiently by 2.0 +/- 0.3 mmol/l when the glucagon rate was increased and glucose production increased by 1.4 +/- 0.5 micromol/kg(-1)/min(-1). In protocol 2, the insulin infusion rate (1.85 +/- 0.36 nmol/kg(-1)/min(-1)) required to maintain glycemia was 3.3-fold higher than during protocol 1. Glucagon-induced stimulation of glycemia (by 1.47 +/- 0.5 mmol/l) and endogenous glucose production (by 0.8 +/- 0.3 micromol/kg(-1)/min(-1)) were blunted, but not abolished. In protocol 3, endogenous glucose production was suppressed by 75% by hyperinsulinemia and was not stimulated when the glucagon infusion rate was increased. In protocol 4, endogenous glucose production did not change significantly with time. CONCLUSION: These results indicate that high dose glucocorticoids induce a marked hepatic insulin resistance. Stimulation of glucose production by hyperglucagonemia was maintained in spite of hyperinsulinemia which can be attributed to either hepatic insulin resistance and/or increased hepatic glucagon sensitivity.

Metabolism of carbamazepine by CYP3A6: a model for in vitro drug interactions studies.

Carbamazepine (CBZ) is widely used in the treatment of epilepsy. The drug is principally metabolized by CYPs to 10, 11-epoxy carbamazepine (CBZ-E) but this metabolite more toxic than the parent drug, does possess anticonvulsant properties. In humans, CYP3A4, CYP2C8 and CYP1A2 have been shown to be implicated in CBZ biotransformation. Our purpose was to establish an experimental model to determine the interaction of CBZ with other antiepileptic drugs. We first identified the CYP isoforms that metabolized CBZ in rabbit. We used liver microsomes from rabbit treated with various compounds known to induce principally some CYPs subfamilies. Having tested all the compounds we demonstrated that only the animals treated with CYP3A inducers were able to metabolize CBZ strongly. The CBZ biotransformation was inhibited by anti CYP3A antibodies. All the CYP3A subfamily substrates specifically decrease CBZ-E formation. In our experiment we did not observe any inhibition with CYP2C substrate. These data provide evidence that in rabbit the CYP3A subfamily is primarily involved in CBZ metabolism. Using this model we investigated the interaction of CBZ with phenobarbital, phenytoin, ethosuccimide, primidone, progabide, vigabatrin and lamotrigine.

Molecular typing of Streptococcus suis isolates from Iberian pigs: a comparison with isolates from common intensively-reared commercial pig breeds.

The Iberian pig (IP) is a traditional Spanish breed variety of the domestic pig (Sus scrofa domesticus) with high economic importance because of the value of the dry-cured products in national and international markets. The genetic characteristics of tonsillar and clinical Streptococcus suis isolates from the IP maintained under extensive or intensive management conditions were investigated. S. suis isolates from IP pigs were compared with S. suis isolates from intensively-farmed pigs of common breeds (CBP). S. suis was isolated from 48.4% of the IP tonsils examined, indicating wide distribution among IP pigs. Serotypes 1 (9.4%), 2 (8.6%) and 9 (7%) were the most commonly found, although a high percentage of S. suis isolates were not typeable by coagglutination testing. No significant differences in carrier rates or serotype diversity were observed between management systems, indicating that intensive farming does not influence S. suis colonisation. Both pulsed-field gel electrophoresis and multiple-locus variable number tandem repeat analysis showed a serotype-based distribution of S. suis IP isolates. Serotypes 1 and 2 S. suis isolates were grouped in the same cluster, whereas isolates of serotypes 9 and 7 were assigned to another cluster. All clinical and most tonsillar serotype 2 IP isolates were assigned to sequence type 1 (ST1) and exhibited the virulence genotype mrp+/epf+/sly+, indicating a high distribution of this genetic lineage among IP as well as a population of serotype 2 common to IPs and CBPs. The only clinical isolate of serotype 9 from IP was assigned to ST123, a sequence type associated with clinical isolates in CBPs in Spain.

Factores de riesgo asociados a la hernia inguinal recurrente en el adulto mayor / Risk factors associated with recurrent inguinal hernia in the elderly

Resumen Objetivo: Evaluar la asociación entre algunos factores de riesgo y la hernia inguinal recurrente en el adulto mayor. Materiales y Método: Se realizó un estudio analítico de casos y controles en el decenio 2002-2011 en el Hospital "Celia Sánchez Manduley", de Manzanillo, Cuba. Se realizó inicialmente un análisis univariado, los factores que resultaron estadísticamente significativos en este último fueron escogidos para el análisis multivariado posterior. Resultados: En el análisis univariado se asociaron 11 variables a la recurrencia herniaria inguinal, excepto la Diabetes mellitus (p = 0,051). En el análisis multivariado se obtuvo un modelo más ajustado con las siguientes variables: demora mayor o igual a 3 años para la primera reparación (p = 0,00), cirugía urgente (p = 0,00) y deslizamiento de la hernia primaria (p = 0,00). Discusión: La demora en la cirugía implica que el paciente sea cada día más añoso y la hernia más compleja, aumentando el riesgo de padecer enfermedades crónicas que agravan el pronóstico dando lugar a la recurrencia herniaria. Por otro lado, los riesgos que implica llevar a cabo la cirugía en la hernia inguinal complicada: aumento del tiempo quirúrgico, edema y tumefacción del complejo músculo-fascioaponeurótico, así como por el riesgo de infección del sitio operatorio. En las hernias inguinales deslizadas las recidivas son más frecuentes, debiéndose probablemente al alto grado de complejidad desde el punto de vista de su reparación. Conclusión: La demora mayor o igual a 3 años para la primera reparación, la cirugía urgente y el deslizamiento de la hernia primaria se asociaron significativamente a la hernia inguinal recurrente en el adulto mayor.

Objective: To evaluate the association between some risk factors and recurrent inguinal hernia in the elderly. Materials and Method: An analytical case-control study was conducted in the 2002-2011 decade at the "Celia Sánchez Manduley" Hospital, of Manzanillo, Cuba. Initially, a univariate analysis was performed, factors that were statistically significant in the latter were chosen for the subsequent multivariate analysis. Results: In the univariate analysis, 11 variables were associated with inguinal hernia recurrence, except diabetes mellitus (p = 0.051). In the multivariate analysis a more adjusted model was obtained with the following variables: delay greater than or equal to 3 years for the first repair (p = 0.00), urgent surgery (p = 0.00) and sliding of the primary hernia (p = 0.00). Discussion: The delay in surgery implies that the patient is getting older and the hernia complex, increasing the risk of suffering from chronic diseases that aggravate the prognosis giving rise to hernia recurrence. On the other hand, the risks involved in carrying out surgery in complicated inguinal hernia: increased surgical time, edema and swelling of the muscle-fascio-aponeurotic complex, as well as the risk of infection of the operative site. In inguinal hernias slipped recurrences are more frequent, probably due to the high degree of complexity from the point of view of their repair. Conclusion: The delay greater than or equal to 3 years for the first repair, urgent surgery and the sliding of the primary hernia were associated significantly to recurrent inguinal hernia in the elderly

Does Early Decompressive Craniectomy Improve Outcome? Experience from an Active UK Recruiter Centre.

Introduction. The results of the recent DECRA study suggest that although craniectomy decreases ICP and ICU length of stay, it is also associated with worst outcomes. Our experience, illustrated by these two striking cases, supports that early decompressive craniectomy may significantly improve the outcome in selected patients. Case Reports. The first patient, a 20-year-old man who suffered severe brain contusion and subarachnoid haemorrhage after a fall downstairs, with refractory ICP of 35 mmHg, despite maximal medical therapy, eventually underwent decompressive craniectomy. After 18 days in intensive care, he was discharged for rehabilitation. The second patient, a 23-year-old man was found at the scene of a road accident with a GCS of 3 and fixed, dilated pupils who underwent extensive unilateral decompressive craniectomy for refractory intracranial hypertension. After three weeks of cooling, paralysis, and neuroprotection, he eventually left ICU for rehabilitation. Outcomes. Four months after leaving ICU, the first patient abseiled 40 m down the main building of St. Mary's Hospital to raise money for the Trauma Unit. He has returned to part-time work. The second patient, was decannulated less than a month later and made a full cognitive recovery. A year later, with a titanium skull prosthesis, he is back to part-time work and to playing football. Conclusions. Despite the conclusions of the DECRA study, our experience of the use of early decompressive craniectomy has been associated with outstanding outcomes. We are currently actively recruiting patients into the RESCUEicp trial and have high hopes that it will clarify the role of the decompressive craniectomy in traumatic brain injury and whether it effectively improves outcomes.

Genetic analysis of Streptococcus suis isolates from wild rabbits.

This work aims to investigate the presence of Streptococcus suis in wild rabbits. A total of 65 S. suis isolates were recovered from 33.3% of the wild rabbits examined. Most isolates (86.2%) belong to genotype cps9. These isolates were further characterized by pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and virulence genotyping. Overall, S. suis exhibited a low genetic diversity. Only 5 genetic profiles were obtained by PFGE and most isolates (71.4%) were included in two pulsotypes that were also widely distributed among the wild rabbit population. MLST analysis assigned all cps9 isolates into three new singlestones (ST216, ST217 and ST284), which were not genetically related to the European ST87 and Spanish ST61 widespread swine clones, indicating a different genetic background for the S. suis isolates from wild rabbits and pigs. Wild rabbit isolates exhibited the genotype mrp-/epf-/sly-, different from those showed by most of the swine S. suis isolates of the ST87 and ST61 clones. None of the S. suis isolated from wild rabbits exhibited the genotype cps2/mrp+/epf+/sly+ associated with human infections. These results indicate that S. suis isolates from wild rabbits are not genetically related with prevalent clones usually associated with infections in pigs or humans in Europe and do not exhibit either their virulence genotypes. Therefore, although wild rabbits could represent an unknown reservoir of this pathogen, they could not represent a potential risk for pigs or humans.

Sutura laparoscópica frente a sutura por laparotomía en úlceras gastroduodenales perforadas / Laparoscopic suture facing laparotomy suture in perforated gastroduodenal ulcers

Resumen Introducción La perforación gastroduodenal continúa siendo una urgencia quirúrgica relativamente frecuente, a pesar de los avances realizados en el tratamiento médico de la enfermedad ulcerosa. Su abordaje laparoscópico ha ido aumentando en los últimos años, aunque no se ha generalizado. Nuestro objetivo es analizar los resultados postoperatorios en pacientes con úlcera perforada tratados mediante sutura laparoscópica, y compararlos con un grupo similar con sutura por laparotomía. Mantenemos la hipótesis de que la sutura laparoscópica es una opción segura y con menor morbilidad que el abordaje por laparotomía. Material y Métodos Análisis retrospectivo comparativo de dos cohortes de pacientes: una tratada mediante sutura laparoscópica durante los años 2014 y 2015, período en el que este abordaje estaba plenamente implantado en la Urgencia en nuestro hospital, y otro grupo comparable tratado mediante sutura por cirugía abierta durante el período 2001-2003. Se analizaron las complicaciones según la clasificación de Clavien-Dindo, tasa de conversión, estancia media y mortalidad. Resultados Los grupos eran comparables en edad, sexo, comorbilidades y riesgo anestésico. Se observó una tendencia a la superioridad a favor del abordaje laparoscópico en ciertas variables analizadas, con una tasa de conversión de un 3%. La presencia de complicaciones postoperatorias precoces fue mayor en el grupo con sutura por laparotomía: shock séptico postquirúrgico (15,2 % vs 6%) e infección de herida (15,2 % vs 3%), así como las complicaciones médicas, aunque de forma no significativa. El grupo tratado con sutura laparoscópica tuvo un mayor tiempo quirúrgico, menor estancia media y menor mortalidad. Conclusión La sutura laparoscópica de la úlcera gastroduodenal en nuestro centro ha tenido una baja tasa de conversión y una morbilidad algo menor a la sutura por laparotomía, con una menor tasa de reintervenciones y menor estancia media, a pesar de un mayor tiempo quirúrgico.

Introduction Gastroduodenal perforation continues to be a relatively frequent surgical emergency, despite advances in the medical treatment of ulcer disease. Its laparoscopic approach has been increasing in the last years, although it has not been generalized. Objective Was to analyze the postoperative results in patients with perforated ulcer treated with laparoscopic suture, and to compare them with a similar group with laparotomy suture. Our hypothesis was that laparoscopic suture is a safe option and with less morbidity than the laparotomy approach. Material and Methods Comparative retrospective analysis of two patient cohorts: one treated with laparoscopic suture during 2014 and 2015, a period in which this approach was fully implanted in the emergency room in our hospital, and another comparable group treated by suture for open surgery during the period 2001-2003. Complications were analyzed according to Clavien-Dindo classification, conversion rate, mean stay and mortality. Results The groups were comparable in age, sex, comorbidities and anesthetic risk. There was a trend towards superiority in favor of the laparoscopic approach in certain variables analyzed, with a conversion rate of 3%. The presence of early postoperative complications was greater in the laparotomy suture group: post-surgical septic shock (15.2% vs 6%) and wound infection (15.2% vs 3%), as well as medical complications, although not significantly. The group with laparoscopic suture had a longer surgical time, lower mean stay and lower mortality. Conclusion The laparoscopic suture of the gastroduodenal ulcer in our center has had a very low conversion rate and a somewhat lower morbidity to the laparotomy suture, with a lower rate of reinterventions and a mean stay, despite a longer surgical time.

Streptococcus plurextorum sp. nov., isolated from pigs.

Biochemical and molecular genetic studies were performed on an unknown Gram-positive, catalase-negative, coccus-shaped organism isolated from clinical samples from pigs. On the basis of the results of cellular morphological and biochemical tests, the organism was identified as a streptococcal species. 16S rRNA gene sequence comparisons confirmed its identification as a member of the genus Streptococcus, but the organism was distinct from any recognized species of this genus. The closest phylogenetic relative of the unknown organism corresponded to Streptococcus suis NCTC 10234(T) (97.2 % 16S rRNA gene sequence similarity) and this phylogenetic position was confirmed by analysis of rpoB and sodA sequences. DNA-DNA hybridization studies showed that the unidentified organism produced a DNA reassociation value of 36.6 % with respect to S. suis NCTC 10234(T). The novel bacterium was distinguished from S. suis and other Streptococcus species using biochemical tests. On the basis of phenotypic and phylogenetic data, the unidentified organism represents a novel species of the genus Streptococcus, for which the name Streptococcus plurextorum sp. nov. is proposed. The type strain is 1956-02(T) (=CECT 7308(T)=CCUG 52972(T)).

High-throughput sample handling and data collection at synchrotrons: embedding the ESRF into the high-throughput gene-to-structure pipeline.

An automatic data-collection system has been implemented and installed on seven insertion-device beamlines and a bending-magnet beamline at the ESRF (European Synchrotron Radiation Facility) as part of the SPINE (Structural Proteomics In Europe) development of an automated structure-determination pipeline. The system allows remote interaction with beamline-control systems and automatic sample mounting, alignment, characterization, data collection and processing. Reports of all actions taken are available for inspection via database modules and web services.

The "temporal processing deficit" hypothesis in dyslexia: new experimental evidence.

The notion that developmental dyslexia may result from a general, nonspecific, defect in perceiving rapidly changing auditory signals is a current subject of debate (so-called "temporal processing deficit" hypothesis). Thirteen phonological dyslexics (age 10-13 years) and 10 controls matched for chronological and reading age were compared on a temporal order judgment (TOJ) task using the succession of two consonants (/p/-/s/) within a cluster. In order to test the relevance of the temporal deficit hypothesis, the task also included two additional conditions where either the two stimuli were artificially slowed or the interstimulus interval was expanded. As expected, the TOJ performance was significantly poorer in dyslexics than in controls. Moreover, in the "slowed speech" condition dyslexics' performance improved to reach the normal controls' level, whereas no significant improvement occurred when increasing the interstimulus interval. Finally dyslexics' performances, especially on the slowed condition, were found correlated with several tests of phonological processing (phoneme deletion, rhyme judgment, and nonword spelling tasks). These results lend support to the general temporal deficit theory of dyslexia.

Contextual factors in neophobia and its habituation: the role of absolute and relative novelty.

In four experiments we investigated the role of contextual cues in the habituation of neophobia in rats. Experiment 1 showed that the consumption of a novel flavour increased across a series of presentations in one context (A) but fell when the flavour was subsequently presented in a second, novel, context (B). In Experiments 2 and 3, subjects again received exposure to a flavour in context A, but also were familiarized with the test context, B. These subjects consumed the flavour with equal readiness, whether it was presented in Context A or in Context B at test. Experiment 4 replicated the results of Experiment 1 and also showed that the consumption of a novel flavour was not influenced by whether it was presented in a novel or a familiar context. Several mechanisms by which the novelty or familiarity of the context might interact with the novelty or familiarity of the flavour were discussed.