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Ben Smith

Publications and source records attributed to Ben Smith.

11 recordsLinked to original sources
PubMed2006

Emotion and psychosis: links between depression, self-esteem, negative schematic beliefs and delusions and hallucinations.

BACKGROUND: The role of emotion in psychosis is being increasingly recognised. Cognitive conceptualisations of psychosis (e.g. [Garety, P.A., Kuipers, E.K., Fowler, D., Freeman, D., Bebbington, P.E., 2001. A cognitive model of the positive symptoms of psychosis. Psychological Medicine, 31, 189-195]) emphasise a central, normal, direct and non-defensive role for negative emotion in the development and maintenance of psychosis. This study tests specific predictions made by Garety et al. [Garety, P.A., Kuipers, E.K., Fowler, D., Freeman, D., Bebbington, P.E., 2001. A cognitive model of the positive symptoms of psychosis. Psychological Medicine, 31, 189-195] about the role of emotion and negative evaluative beliefs in psychosis. METHODS: 100 participants who had suffered a recent relapse in psychosis were recruited at baseline for the Prevention of Relapse in Psychosis (PRP) trial. In a cross-sectional analysis, we examined the role of depression, self-esteem and negative evaluative beliefs in relation to specific positive symptoms (persecutory delusions, auditory hallucinations and grandiose delusions) and symptom dimensions (e.g. distress, negative content, pre-occupation and conviction). RESULTS: Analysis indicated that individuals with more depression and lower self-esteem had auditory hallucinations of greater severity and more intensely negative content, and were more distressed by them. In addition, individuals with more depression, lower self-esteem and more negative evaluations about themselves and others had persecutory delusions of greater severity and were more pre-occupied and distressed by them. The severity of grandiose delusions was related inversely to depression scores and negative evaluations about self, and directly to higher self-esteem. CONCLUSIONS: This study provides evidence for the role of emotion in schizophrenia spectrum-disorders. Mood, self-esteem and negative evaluative beliefs should be considered when conceptualising psychosis and designing interventions.

Adolescent↗
PubMed2006

The Brief Core Schema Scales (BCSS): psychometric properties and associations with paranoia and grandiosity in non-clinical and psychosis samples.

BACKGROUND: Traditional instruments that measure self-esteem may not relate directly to the schema construct as outlined in recent cognitive models. The Brief Core Schema Scales (BCSS) aim to provide a theoretically coherent self-report assessment of schemata concerning self and others in psychosis. The scales assess four dimensions of self and other evaluation: negative-self, positive-self, negative-other, positive-other. METHOD: We analysed the psychometric properties of the BCSS using a sample of 754 students recruited by email and 252 people with psychosis recruited as part of a trial of cognitive therapy. We report the internal consistency, stability and the factor structure of the scale, and the association of the BCSS with measures of self-esteem and with symptoms of paranoia and grandiosity. RESULTS: The BCSS have good psychometric properties and have more independence from mood than the Rosenberg Self-Esteem Schedule. People with chronic psychosis reported extreme negative evaluations of both self and others on these scales, but their levels of self-esteem and positive evaluations of self and others were similar to the student sample. CONCLUSIONS: Extreme negative evaluations of self and others appear to be characteristic of the appraisals of people with chronic psychosis, and are associated with symptoms of grandiosity and paranoia in the non-clinical population. The BCSS may provide a more useful measure of schemata about self and others than traditional measures of self-esteem.

Adult↗
PubMed2006

Evidence for an intermediate colony morphology of Vibrio vulnificus.

Vibrio vulnificus causes both food-borne disease and wound infections. Most V. vulnificus strains express capsular polysaccharide (CPS), which is required for the virulence of this organism. Under standard growth conditions, CPS expression is lost at a relatively high frequency (10(-3) to 10(-4)), resulting in a switch from an opaque (Op, CPS+) colony morphology to a translucent (Tr, CPS-) colony morphology. The wzb gene, which encodes a phosphatase required for CPS expression, has been proposed to be involved in this switch through a site-specific deletion of the entire gene. In an examination of five strains, we found that the frequency of wzb deletion in Tr colonies varies by strain and therefore does not account for all the Tr colonies that are seen. In addition, we have identified a third, intermediate (Int) colony morphotype, in which the colonies appear less opaque but are not fully translucent. PCR studies have demonstrated that Int colonies still contain the wzb gene, while reverse transcriptase PCR studies have shown that although Int strains retain expression of wzb, in some cases the transcription of wzb is reduced. Int strains switch to a true Tr (wzb negative) morphotype at a very high frequency (nearly 100%) under certain conditions. Finally, Int colonies, which in some cases can easily be mistaken for Tr colonies, have been observed to occasionally revert to Op, while Tr colonies containing a wzb deletion presumably are unable to revert to the encapsulated form.

Base Sequence↗
PubMed2006

In situ and in vitro gene expression by Vibrio vulnificus during entry into, persistence within, and resuscitation from the viable but nonculturable state.

Isolation of Vibrio vulnificus during winter months is difficult due to the entrance of these cells into the viable but nonculturable (VBNC) state. While several studies have investigated in vitro gene expression upon entrance into and persistence within the VBNC state, to our knowledge, no in situ studies have been reported. We incubated clinical and environmental isolates of V. vulnificus in estuarine waters during winter months to monitor the expression of several genes during the VBNC state and compared these to results from in vitro studies. katG (periplasmic catalase) was down-regulated during the VBNC state in vitro and in situ compared to the constitutively expressed gene tufA. Our results indicate that the loss of catalase activity we previously reported is a direct result of katG repression, which likely accounts for the VBNC response of this pathogen. While expression of vvhA (hemolysin) was detectable in environmental strains during in situ incubation, it ceased in all cases by ca. 1 h. These results suggest that the natural role of hemolysin in V. vulnificus may be in osmoprotection and/or the cold shock response. Differences in expression of the capsular genes wza and wzb were observed in the two recently reported genotypes of this species. Expression of rpoS, encoding the stress sigma factor RpoS, was continuous upon entry into the VBNC state during both in situ and in vitro studies. We found the half-life of mRNA to be less than 60 minutes, confirming that mRNA detection in these VBNC cells is a result of de novo RNA synthesis.

Bacterial Proteins↗
PubMed2006

In situ gene expression by Vibrio vulnificus.

Strains of Vibrio vulnificus incubated in situ in natural estuarine waters during warm months continued to express katG (periplasmic catalase), rpoS (stress sigma factor), tufA (elongation factor), wza, and wzb (capsule synthesis). vvhA (hemolysin) was differentially expressed between environmental and clinical isolates. These results paralleled our in vitro findings.

Bacterial Capsules↗
PubMed2005

Ecosystem service supply and vulnerability to global change in Europe.

Global change will alter the supply of ecosystem services that are vital for human well-being. To investigate ecosystem service supply during the 21st century, we used a range of ecosystem models and scenarios of climate and land-use change to conduct a Europe-wide assessment. Large changes in climate and land use typically resulted in large changes in ecosystem service supply. Some of these trends may be positive (for example, increases in forest area and productivity) or offer opportunities (for example, "surplus land" for agricultural extensification and bioenergy production). However, many changes increase vulnerability as a result of a decreasing supply of ecosystem services (for example, declining soil fertility, declining water availability, increasing risk of forest fires), especially in the Mediterranean and mountain regions.

Agriculture↗
PubMed2005

Trauma and hallucinatory experience in psychosis.

Recent research indicates that there may be phenomenological, symptom, and diagnostic associations between trauma and hallucinations. However, the nature of the relationship is poorly understood from a psychological perspective. We report a theoretically informed phenomenological study. From descriptions of reported traumas and hallucinations, we assessed the rates of four types of hypothesized association between traumas and hallucinations (direct, indirect, stress, and none) in 75 participants with nonaffective psychosis. In a subgroup who had experienced trauma (N = 40), 12.5% had hallucinations with similar themes and content to their traumas, 45% had hallucinations in which the themes were the same but not the content, and 42.5% had no identifiable associations between their hallucinations and previously experienced trauma. Traumas rated as intrusive were significantly associated with hallucinations rated as intrusive, although intrusive hallucinations were not associated with traumas in general. The traumas most likely to be associated with hallucinations were sexual abuse and bullying.

Accidents↗
PubMed2003

Community-based group exercise improves balance and reduces falls in at-risk older people: a randomised controlled trial.

BACKGROUND: recent studies have found that moderate intensity exercise is an effective intervention strategy for preventing falls in older people. However, research is required to determine whether supervised group exercise programmes, conducted in community settings with at-risk older people referred by their health care practitioner are also effective in improving physical functioning and preventing falls in this group. OBJECTIVES: to determine whether participation in a weekly group exercise programme with ancillary home exercises over one year improves balance, muscle strength, reaction time, physical functioning, health status and prevents falls in at-risk community-dwelling older people. METHODS: the sample comprised 163 people aged over 65 years identified as at risk of falling using a standardised assessment screen by their general practitioner or hospital-based physiotherapist, residing in South Western Sydney, Australia. Subjects were randomised into either an exercise intervention group or a control group. Physical performance and general health measures were assessed at baseline and repeated 6-months into the trial. Falls were measured over a 12-month follow-up period using monthly postal surveys. RESULTS: at baseline both groups were well matched in their physical performance, health and activity levels. The intervention subjects attended a median of 23 exercise classes over the year, and most undertook the home exercise sessions at least weekly. At retest, the exercise group performed significantly better than the controls in three of six balance measures; postural sway on the floor with eyes open and eyes closed and coordinated stability. The groups did not differ at retest in measures of strength, reaction time and walking speed or on Short-Form 36, Physical Activity Scale for the Elderly or fear of falling scales. Within the 12-month trial period, the rate of falls in the intervention group was 40% lower than that of the control group (IRR=0.60, 95% CI 0.36-0.99). CONCLUSIONS: these findings indicate that participation in a weekly group exercise programme with ancillary home exercises can improve balance and reduce the rate of falling in at-risk community dwelling older people.

Accidental Falls↗
PubMed2000

A controlled trial of behavioural education to promote exercise among physiotherapy outpatients.

This pilot study aimed to test a behavioural intervention by outpatient physiotherapists to promote moderate physical activity among their clients for general health reasons. A quasi-experimental study was conducted with 204 subjects. The intervention consisted of behavioural counselling, information brochures and a physical activity diary. Self-reported physical activity was measured at baseline and at six weeks follow-up. At follow-up, the improvements in total minutes of physical activity using the preceding week as the recall period were substantial in both the control and intervention groups, but not significantly different. In the average weekly physical activity reported by subjects for the preceding six months, intervention subjects were significantly more likely to report a 60min/wk improvement than controls (adjusted odds ratio 2.97, 95% confidence interval [CI] 1.36-6.46). However, this was the only significant difference evident between the groups in the average weekly physical activity measures. Pre- and post-surveys completed by participating physiotherapists showed marked improvements in their knowledge and confidence regarding physical activity promotion. While the capacity of outpatient physiotherapists to educate clients about physical activity for non-therapeutic reasons can be improved, the most effective intervention model for clients in this setting remains unclear.

Journal Article↗