The ß-adrenoceptor blocker propranolol ameliorates compulsive-like gambling behaviour in a rodent slot machine task: implications for iatrogenic gambling disorder.

Previous work has shown that chronic administration of the dopamine D2/3 receptor agonist ropinirole invigorates performance on a rodent slot machine task (rSMT). This behavioural change appears superficially similar to the iatrogenic gambling disorder (GD) observed in a sub-set of patients with Parkinson's disease (PD), and has been associated with increased activation of the intra-cellular signalling proteins GSK3ß and CREB in the striatum. Here, we wanted to determine whether this response to ropinirole could be attenuated by targeting these signalling proteins, and if the loss of dopaminergic innervation characteristic of PD would alter ropinirole's effects on the rSMT. Male Long Evans rats were trained on the rSMT. Dopaminergic terminals innervating the dorsolateral striatum were then lesioned bilaterally using the neurotoxin 6-hydroxydopamine hydrochloride (6-OHDA). Subsequently animals were implanted with osmotic mini-pumps delivering ropinirole. Lastly, animals were given dietary lithium (Li+ ), to inhibit the activation of GSK3ß, or injections of the ß-adrenoceptor antagonist propranolol, which potently inhibits CREB as a secondary mechanism of action, and any changes in ropinirole-induced increases in compulsive-like engagement in the rSMT evaluated. Chronic ropinirole increased the number of trials animals completed, reproducing our original finding. This increase in task engagement was not altered in animals with 6-OHDA lesions, a putative model of early PD. In addition, the effects of ropinirole were not attenuated by administration of Li+ , but were ameliorated by propranolol. These data suggest that propranolol may represent a potential pharmacotherapy for the treatment of iatrogenic gambling.

Adverse obstetric history is not a risk factor for poor outcome after ventral rectopexy for obstructive defaecation syndrome.

AIM: Ventral rectopexy (VR) has gained popularity in the management of obstructive defaecation syndrome (ODS) due to a symptomatic rectocele ± intussusception. Data on the efficacy and safety of VR are variable and there are few predictors of successful outcome. This study aimed to examine whether or not an adverse obstetric history influenced the functional outcome following VR for ODS. METHOD: This was a retrospective study of a cohort of 76 consecutive patients who had undergone VR for ODS at a tertiary referral centre between 2012 and 2015. Patients were followed up by telephone questionnaire. The obstetric history and pre- and postoperative symptoms of ODS and faecal incontinence (FI) were obtained from telephone interviews. RESULTS: In this cohort, symptoms of ODS were significantly improved by surgery, with 56% of patients showing a reduction of symptoms of 50% or more (P < 0.001). Subgroup analysis demonstrated that a lower body mass index (BMI; 24.4 vs 27.3 kg/m2 ; P < 0.05) and shorter duration of symptoms (7 vs 10 years; P < 0.05) led to a better outcome. VR had no effect on FI. Obstetric factors such as foetal weight, instrumental delivery, episiotomy, perineal tear and total number of deliveries did not influence outcomes. CONCLUSION: Patients with a less straightforward obstetric history can be reassured that this should not adversely influence the functional outcome after VR for ODS. Colorectal surgeons who offer this surgery should warn patients with an elevated BMI or with longstanding symptoms that the operation may be less successful than for those with a lower BMI or shorter duration of symptoms.

Computational approaches to modeling gambling behaviour: Opportunities for understanding disordered gambling.

Computational modeling has become an important tool in neuroscience and psychiatry research to provide insight into the cognitive processes underlying normal and pathological behavior. There are two modeling frameworks, reinforcement learning (RL) and drift diffusion modeling (DDM), that are well-developed in cognitive science, and have begun to be applied to Gambling Disorder. RL models focus on explaining how an agent uses reward to learn about the environment and make decisions based on outcomes. The DDM is a binary choice framework that breaks down decision making into psychologically meaningful components based on choice reaction time analyses. Both approaches have begun to yield insight into aspects of cognition that are important for, but not unique to, gambling, and thus relevant to the development of Gambling Disorder. However, these approaches also oversimplify or neglect various aspects of decision making seen in real-world gambling behavior. Gambling Disorder presents an opportunity for 'bespoke' modeling approaches to consider these neglected components. In this review, we discuss studies that have used RL and DDM frameworks to investigate some of the key cognitive components in gambling and Gambling Disorder. We also include an overview of Bayesian models, a methodology that could be useful for more tailored modeling approaches. We highlight areas in which computational modeling could enable progression in the investigation of the cognitive mechanisms relevant to gambling.

Comparison of Arcobacter isolation methods, and diversity of Arcobacter spp. in Cheshire, United Kingdom.

The aims of this study were, firstly, to compare five published methods for the isolation of Arcobacter spp. from animal feces in order to determine the most sensitive and specific method. Second, we analyzed the resulting isolates by multilocus sequence typing (MLST) in order to investigate the diversity of the isolates recovered. Third, we investigated the ability to recover Arcobacter spp. from frozen fecal samples. Seventy-seven fecal samples from cattle, sheep, and badgers were subjected to five isolation methods, based on published methods for the isolation of Arcobacter and Campylobacter spp. Thirty-nine Arcobacter butzleri isolates were analyzed using a multilocus sequence typing scheme. The survival of Arcobacter spp. in frozen samples was investigated by freezing the fecal samples at -80°C for 7 days and then applying the same five isolation methods. The most sensitive and specific method used an Arcobacter-specific broth in conjunction with modified charcoal cefoperazone deoxycholate agar (mCCDA) with added antibiotics. Freezing of fecal samples led to a reduction in the recovery of Arcobacter spp. by approximately 50%. The 39 allelic profiles obtained by MLST could be divided into 11 sequence types (STs). We have identified the most sensitive and specific method for the isolation of Arcobacter spp. from animal feces and demonstrated that the freezing of fecal samples prior to isolation reduces arcobacter recovery. MLST analysis of the isolates revealed a high level of diversity.

Isolation of a novel Campylobacter jejuni clone associated with the bank vole, Myodes glareolus.

Campylobacter jejuni can be isolated from different animal hosts. Various studies have used multilocus sequence typing to look for associations between particular clones of C. jejuni and specific hosts. Here, we describe the isolation of a novel clone (sequence type 3704 [ST-3704]) of C. jejuni associated with the bank vole (Myodes glareolus).

Transmission of Pseudomonas aeruginosa epidemic strain from a patient with cystic fibrosis to a pet cat.

Chronic infection with Pseudomonas aeruginosa is common in cystic fibrosis (CF) and certain strains are more transmissible and virulent than others. Of these, the Liverpool Epidemic Strain (LES) is highly transmissible and cross infection has been reported between patients with CF and healthy non-CF relatives. However, the risk of transmission from humans to animals is unknown. The first report of interspecies transmission of the LES strain of P aeruginosa from an adult patient with CF to a pet cat is described. This development further complicates the issue of infection control policies required to prevent the spread of this organism.

Dietary influences on cognition.

Obesity is a world-wide crisis with profound healthcare and socio-economic implications and it is now clear that the central nervous system (CNS) is a target for the complications of metabolic disorders like obesity. In addition to decreases in physical activity and sedentary lifestyles, diet is proposed to be an important contributor to the etiology and progression of obesity. Unfortunately, there are gaps in our knowledge base related to how dietary choices impact the structural and functional integrity of the CNS. For example, while chronic consumption of hypercaloric diets (increased sugars and fat) contribute to increases in body weight and adiposity characteristic of metabolic disorders, the mechanistic basis for neurocognitive deficits in obesity remains to be determined. In addition, studies indicate that acute consumption of hypercaloric diets impairs performance in a wide variety of cognitive domains, even in normal non-obese control subjects. These results from the clinical and basic science literature indicate that diet can have rapid, as well as long lasting effects on cognitive function. This review summarizes our symposium at the 2017 Society for the Study of Ingestive Behavior (SSIB) meeting that discussed these effects of diet on cognition. Collectively, this review highlights the need for integrated and comprehensive approaches to more fully determine how diet impacts behavior and cognition under physiological conditions and in metabolic disorders like type 2 diabetes mellitus (T2DM) and obesity.

Inactivation of the orbitofrontal cortex reduces irrational choice on a rodent Betting Task.

Cognitive biases may play a significant role in disorders of decision making such as pathological gambling and addiction. Understanding the neurobiology of these biases could lead to more effective pharmacological and therapeutic treatments for disorders in which aberrant decision making is prominent. The rodent Betting Task (rBT) was designed to measure one commonly observed decision-making heuristic in rodents, namely "escalation of commitment" in which subjects become more risk averse as the stakes increase, even if the odds of success remain constant. In the rodent task, the animal is presented with a choice between two options of equivalent expected value, such that reward on one option is guaranteed while the other has a 50% chance of double the prize or nothing. Past work has shown that a subset of animals (termed wager sensitive) adopt an irrationally risk-averse choice preference in which they shift their choice away from the uncertain option as the bet size grows larger. In the current study, the orbitofrontal (OFC), prelimbic (PrL), and infralimbic cortex (IL) were inactivated to evaluate the contributions made by these regions to choice behavior on the rBT. Inactivation of the OFC (but not the IL or the PrL) selectively ameliorated the risk-averse choice pattern characteristic of wager-sensitive animals. This finding suggests that the OFC may have a relatively unique role in promoting this type of non-normative decision-making under uncertainty, an effect that is potentially related to its role in representing the subjective value of reinforcing outcomes.

Elucidating the role of D4 receptors in mediating attributions of salience to incentive stimuli on Pavlovian conditioned approach and conditioned reinforcement paradigms.

The power of drug-associated cues to instigate drug 'wanting' and consequently promote drug seeking is a corner stone of contemporary theories of addiction. Gambling disorder has recently been added to the pantheon of addictive disorders due to the phenomenological similarities between the diseases. However, the neurobiological mechanism that may mediate increased sensitivity towards conditioned stimuli in addictive disorders is unclear. We have previously demonstrated using a rodent analogue of a simple slot machine that the dopamine D4 receptor is critically engaged in controlling animals' attribution of salience to stimuli associated with reward in this paradigm, and consequently may represent a target for the treatment of gambling disorder. Here, we investigated the role of acute administration of a D4 receptor agonist on animals' responsivity to conditioned stimuli on both a Pavlovian conditioned approach (autoshaping) and a conditioned reinforcement paradigm. Following training on one of the two tasks, separate cohorts of rats (male and female) were administered a dose of PD168077 shown to be maximally effective at precipitating errors in reward expectancy on the rat slot machine task (10mg/kg). However, augmenting the activity of the D4 receptors in this manner did not alter behaviour on either task. These data therefore provide novel evidence that the D4 receptor does not alter incentive motivation in response to cues on simple behavioural tasks.

The agranular and granular insula differentially contribute to gambling-like behavior on a rat slot machine task: effects of inactivation and local infusion of a dopamine D4 agonist on reward expectancy.

RATIONALE: Rats, like humans, are susceptible to the reinforcing effects of reward-related stimuli presented within a compound stimulus array, putatively analogous to the so-called near-miss effect. We have previously demonstrated using a rodent slot machine task (rSMT) that the reward expectancy these stimuli elicit is critically mediated by the dopamine D4 receptor. D4 receptors are principally located in prefrontal regions activated during slot machine play in humans, such as the insular cortex. The insula has recently attracted considerable interest as it appears to play a crucial role in substance and behavioral addictions. However, the insula is a heterogeneous area, and the relative contributions of subregions to addictive behaviors are unclear. METHODS: Male Long Evans rats were trained to perform the rSMT, and then bilateral cannula targeting either the granular or agranular insula were implanted. The effects of inactivation and local administration of a D4 agonist were investigated. RESULTS: Temporary inactivation of the agranular, but not the granular insula impaired performance on the rSMT. In contrast, local infusion of the D4 agonist PD168077 into the agranular insula had no effect on task performance, but when administered into the granular insula, it improved animals' ability to differentiate winning from non-winning trials. The agranular insula may therefore modulate decision making when conflicting stimuli are present, potentially due to its role in generating a cohesive emotional percept based on both externally and internally generated signals, whereas the granular insular is not critical for this process. Nevertheless, D4 receptors within the granular insula may amplify the incentive salience of aversive environmental stimuli. DISCUSSION: These data provide insight into the neurobiological mechanism underpinning maladaptive reward expectancy during gambling and provide further evidence that D4 receptors represent a potential target for developing pharmacotherapies for problem gambling.

Activation of dopamine D4 receptors within the anterior cingulate cortex enhances the erroneous expectation of reward on a rat slot machine task.

Using a rodent slot machine task (rSMT), we have previously shown that rats, like humans, are susceptible to the reinforcing effects of winning signals presented within a compound stimulus array, even when the pattern generated predicts a negative rather than a positive outcome such as during a "near-miss". The dopamine D4 receptor critically mediates the erroneous reward expectancy generated on such trials. D4 receptors are particularly enriched within frontal and limbic areas activated during slot machine play, such as the anterior cingulate cortex (ACC). We therefore selectively inactivated the ACC to confirm involvement of this region in rSMT performance, and subsequently examined the specific contribution of local D4 receptors. ACC inactivations generally impaired animals' ability to optimally differentiate winning from losing outcomes. Local administration of the D4 agonist PD168077 had a qualitatively similar effect, but increased reward expectancy was only evident on archetypal "near-miss" trials i.e. when the first two of three stimuli in the array were concordant with a rewarding outcome, and only the last stimulus critically signalled a non-win. These data indicate that the ACC is critically involved in parsing the appropriate response when competing stimulus-outcome associations are activated, and that signalling via D4 receptors may play a particularly important role in gating the temporal and spatial summation of salient events. Such findings provide novel insights into the mechanism underlying the erroneous expectations of reward generated when playing slot machines, and suggest a mechanism by which D4 receptor antagonists may be effective in treating gambling disorder.

Environmental contamination with an epidemic strain of Pseudomonas aeruginosa in a Liverpool cystic fibrosis centre, and study of its survival on dry surfaces.

We conducted an environmental survey in the Liverpool adult cystic fibrosis (CF) centre in order to determine the extent of environmental contamination with an epidemic strain of Pseudomonas aeruginosa that colonizes most CF patients in Liverpool, and to identify possible reservoirs and routes of cross-infection. In addition, we studied the survival of this strain on dry surfaces, compared with that of other CF P. aeruginosa strains, to explore factors that might contribute to its high transmissibility. Samples were collected from staff, patients and the environment (drains, bath tubs, showers, dry surfaces, respiratory equipment and air) in the inpatient ward and outpatient clinic. P. aeruginosa strains were tested using a new polymerase chain reaction amplification assay specific for the Liverpool epidemic strain (LES). LES was isolated from patients' hands, clothes and bed linen. Environmental contamination with LES was only detected in close proximity to colonized patients (external surfaces of their respiratory equipment, and spirometry machine tubing and chair) and was short-lived. No persistent environmental reservoirs were found. LES was detected in the majority of air samples from inside patients' rooms, the ward corridor and the outpatient clinic. Survival of LES on dry surfaces was significantly longer than that for some other strains tested, but not compared with other strains shown not to be transmissible. Improved environmental survival on its own, therefore, cannot explain the high transmissibility of this epidemic strain. Our study suggests that airborne dissemination plays a significant role in patient-to-patient spread of LES, and confirms the need to segregate those patients colonized by epidemic P. aeruginosa strains from all other CF patients.

Irrational beliefs, biases and gambling: exploring the role of animal models in elucidating vulnerabilities for the development of pathological gambling.

Gambling is a heterogeneous and complex disorder. Multiple factors may lead to problem gambling, yet one of the most important appears to be the increased presence of cognitive biases or distortions. These biases are thought to precipitate gambling as they can lead to dysfunctional decision making under risk or ambiguity. Modelling these cognitive perturbations in animals can improve our understanding of their neurobiological bases, and potentially stimulate novel treatment options. The first aim of this review is to give a broad overview of some of the cognitive biases that are most commonly associated with gambling. Secondly, we will discuss several animal models that we have developed in which rodent decision-making appears hallmarked by the same cognitive inconsistencies as human choice. In particular, we will discuss two tasks that capture elements of risk and loss averse decision making, and another in which rats appear susceptible to the 'near-miss' effect. To date, findings from both human and non-human studies suggest that these different biases are neuropharmacologically and neurostructurally dissociable, and that dopamine plays a key role in their expression. Lastly, we will briefly discuss areas in both human and animal research where limitations within the field may be hampering a more complete understanding of pathological gambling as a disorder.

SINE-R.C2 (a Homo sapiens specific retroposon) is homologous to CDNA from postmortem brain in schizophrenia and to two loci in the Xq21.3/Yp block linked to handedness and psychosis.

We investigated the retroviral/retroposon hypothesis of schizophrenia by generating sequences with PCR primers based on a retroviral sequence recovered by Yee et al. [1998: Schizophr Res 29:92] from a cDNA library from postmortem brain tissue from an individual with psychosis in a genomic region (Xq21.3) that has been tentatively linked to schizophrenia and schizoaffective disorder by Laval et al. [1998: Am. J. Med. Genet. (Neuropsychiatr. Genet.) 81:420-427]. Within the block of homology with Yp that was generated by a transposition between the chimpanzee and Homo sapiens we find two sequences, HS307 and HS408, with a high degree of homology to but not identity with the schizophrenic brain cDNA. The closest match of these three sequences is to a family of retroposons, that has evolved from the HERV-K family of endogenous retroviruses, some members of which (e.g., SINE-R.C2) appear to be specific to the human genome. This element has been reported as a cause of Fukuyama-type muscular dystrophy [Kobayashi et al., 1998: Nature 394:388-392]. Such retroposons, as agents of change in the human genome, provide a strategy for investigating pathogenesis. On account of their genomic location in a region that has been subject to change in the course of hominid evolution, and that may have a relationship to psychosis and/or cerebral asymmetry, we conclude that these particular insertions deserve further investigation.

A putative type III secretion gene cluster is widely distributed in the Burkholderia cepacia complex but absent from genomovar I.

Using probes constructed from Ralstonia solanacearum and Burkholderia pseudomallei, putative type III secretion (TTS) genes were identified in Burkholderia cepacia J2315 (genomovar III). A cosmid clone containing DNA with homology to five TTS genes was sub-cloned and regions were sequenced in order to design oligonucleotides for polymerase chain reaction assays. These indicated that two putative TTS genes (bcscQ and bcscV) were present in all members of the B. cepacia complex with the exception of strains from genomovar I. Southern blot assays confirmed this observation, suggesting that the lack of a TTS gene cluster may define a major difference between B. cepacia genomovar I and other members of the B. cepacia complex, including genomovar III. In contrast to TTS gene clusters in other bacteria, a putative gene homologous to the virB1 gene of Brucella suis was located directly downstream of bcscQR.

Evidence for the presence in Burkholderia pseudomallei of a type III secretion system-associated gene cluster.

Burkholderia pseudomallei, the causative agent of melioidosis, contains a cluster of putative genes homologous to those encoding HpaP, HrcQ, HrcR, HrcS and HrpV in the plant pathogen Ralstonia solanacearum. In R. solanacearum, these genes form part of a type III secretion-associated pathogenicity island. The order of the genes in B. pseudomallei is directly equivalent to that found in R. solanacearum. The B. pseudomallei proteins share 49.5% (HpaP), 52.6% (HrcQ), 80.0% (HrcR), 72.1% (HrcS) and 46.7% (HrpV) similarity, respectively, with their equivalent R. solanacearum proteins. The presence of type III secretion-associated genes in B. pseudomallei pathogens suggests a possible role for type III secretion systems in the pathogenicity of this organism.

Flagellin gene variation between clinical and environmental isolates of Burkholderia pseudomallei contrasts with the invariance among clinical isolates.

The flagellin gene sequence from a clinical isolate of Burkholderia pseudomallei was used to design oligonucleotide primers for PCR/RFLP analysis of flagellin gene variation among clinical and environmental isolates of B. pseudomallei. Genes from four clinical and six environmental isolates were amplified and compared by RFLP. The clinical isolates were indistinguishable, but variation was detected among some of the environmental isolates. Sequence analysis of flagellin gene amplified products demonstrated high levels of conservation amongst the flagellin genes of clinical isolates (>99% similarity), compared to the variation observed between the clinical isolates and one of the environmental isolates (<90% similarity). Genomic comparisons with pulsed-field gel electrophoresis (PFGE) revealed differences between the relationships inferred by flagellin genotyping and PFGE, suggesting that a combination of molecular methods may be useful for the subtyping of B. pseudomallei strains.

Variation in Bordetella bronchiseptica flaA does not correlate with typing by macro-restriction analysis by pulsed-field gel electrophoresis.

A genotyping method based on PCR-RFLP analysis of the flagellin gene (flaA) was applied to 30 mainly feline isolates of Bordetella bronchiseptica. These isolates were separated into three PCR-RFLP groups with the restriction endonucleases HaeIII, MspI, MboI and RsaI. flaA nucleotide sequences representing each of the three groups differed from each other by 11-13%. One of the groups exhibited far greater flaA sequence identity with the cryptic flagellin gene sequence of B. pertussis (>97%) than with flaA sequences from representatives of the other B. bronchiseptica PCR-RFLP groups. Amongst the 30 isolates were at least 10 representing each of the two major genotypes (A and B) identified in a previous study by macro-restriction analysis and pulsed-field gel electrophoresis (PFGE), as well as representatives of other less common genotypes. Each of the major PFGE genotypes contained strains representing more than one flagellin genotype. Indeed, there was no correlation between the two molecular typing methods. PFGE analysis may identify differences due to genomic re-arrangements rather than genuine variations in gene content. If so, relationships inferred on the basis of PFGE or other molecular methods for whole genome comparison should be treated with caution.

Isolation and characterisation of a novel spirochaete from severe virulent ovine foot rot.

A novel spirochaete was isolated from a case of severe virulent ovine foot rot (SVOFR) by immunomagnetic separation with beads coated with polyclonal anti-treponemal antisera and prolonged anaerobic broth culture. The as yet unnamed treponeme differs considerably from the only other spirochaete isolated from ovine foot rot as regards morphology, enzymic profile and 16S rDNA sequence. On the basis of 16S rDNA, it was most closely related to another unnamed spirochaete isolated from cases of bovine digital dermatitis in the USA, raising the possibility of cross-species transmission. Further information is required to establish this novel ovine spirochaete as the cause of SVOFR.

Flagellin gene sequence variation in the genus Pseudomonas.

Flagellin gene (fliC) sequences from 18 strains of Pseudomonas sensu stricto representing 8 different species, and 9 representative fliC sequences from other members of the gamma sub-division of proteobacteria, were compared. Analysis was performed on N-terminal, C-terminal and whole fliC sequences. The fliC analyses confirmed the inferred relationship between P. mendocina, P. oleovorans and P. aeruginosa based on 16S rRNA sequence comparisons. In addition, the analyses indicated that P. putida PRS2000 was closely related to P. fluorescens SBW25 and P. fluorescens NCIMB 9046T, but suggested that P. putida PaW8 and P. putida PRS2000 were more closely related to other Pseudomonas spp. than they were to each other. There were a number of inconsistencies in inferred evolutionary relationships between strains, depending on the analysis performed. In particular, whole flagellin gene comparisons often differed from those obtained using N- and C-terminal sequences. However, there were also inconsistencies between the terminal region analyses, suggesting that phylogenetic relationships inferred on the basis of fliC sequence should be treated with caution. Although the central domain of fliC is highly variable between Pseudomonas strains, there was evidence of sequence similarities between the central domains of different Pseudomonas fliC sequences. This indicates the possibility of recombination in the central domain of fliC genes within Pseudomonas species, and between these genes and those from other bacteria.