Decreased olfactory discrimination is associated with impulsivity in healthy volunteers

In clinical populations, olfactory abilities parallel executive function, implicating shared neuroanatomical substrates within the ventral prefrontal cortex. In healthy individuals, the relationship between olfaction and personality traits or certain cognitive and behavioural characteristics remains unexplored. We therefore tested if olfactory function is associated with trait and behavioural impulsivity in nonclinical individuals. Eighty-three healthy volunteers (50 females) underwent quantitative assessment of olfactory function (odour detection threshold, discrimination, and identifcation). Each participant was rated for trait impulsivity index using the Barratt Impulsiveness Scale and performed a battery of tasks to assess behavioural impulsivity (Stop Signal Task, SST; Information Sampling Task, IST; Delay Discounting). Lower odour discrimination predicted high ratings in non-planning impulsivity (Barratt Non-Planning impulsivity subscale); both, lower odour discrimination and detection threshold predicted low inhibitory control (SST; increased motor impulsivity). These fndings extend clinical observations to support the hypothesis that defcits in olfactory ability are linked to impulsive tendencies within the healthy population. In particular, the relationship between olfactory abilities and behavioural inhibitory control (in the SST) reinforces evidence for functional overlap between neural networks involved in both processes. These fndings may usefully inform the stratifcation of people at risk of impulse-control-related problems and support planning early clinical interventions

Global urban environmental change drives adaptation in white clover.

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Olfactory identification dysfunction, aggression and impulsivity in war veterans with post-traumatic stress disorder

© 2007 Cambridge University Press. Online edition of the journal is available at http://journals.cambridge.org/PSMBACKGROUND: Due to neuropsychological conceptualizations of orbitoprefrontal cortex (OFC) dysfunction underpinning impulsive aggression and the incidence of such behaviour in post-traumatic stress disorder (PTSD), this study aimed to explore olfactory identification (OI) ability in war veterans with PTSD as a probe of putative OFC dysfunction; and to explore the utility of OI ability in predicting aggressive and impulsive behavior in this clinical population. METHOD: Participants comprised 31 out-patient male war veterans with PTSD (mean=58.23 years, s.d.=2.56) recruited from a Melbourne Veterans Psychiatry Unit, and 31 healthy age- and gender-matched controls (mean=56.84 years, s.d.=7.24). All participants were assessed on clinical measures of PTSD, depression, anxiety, and alcohol misuse; olfactory identification; neurocognitive measures of dorsolateral prefrontal, lateral prefrontal and mesial temporal functioning; and self-report measures of aggression and impulsivity. RESULTS: War veterans with PTSD exhibited significant OI deficits (OIDs) compared to controls, despite uncompromised performance on cognitive measures. OIDs remained after covaring for IQ, anxiety, depression and alcohol misuse, and were significant predictors of aggression and impulsivity. CONCLUSIONS: This research contributes to emerging evidence of orbitoprefrontal dysfunction in the pathophysiology underlying PTSD. This is the first study to report OIDs as a predictor of aggression and impulsivity in this clinical population. It prompts further exploration of the potential diagnostic utility of OIDs in the assessment of PTSD. Such measures may help delineate the clinical complexity of PTSD, and support more targeted interventions for individuals with a greater susceptibility to aggressive and impulsive behaviors.10.1017/S003329170700145

What is the role of routine follow-up for localised limb soft tissue sarcomas? A retrospective analysis of 174 patients

BACKGROUND: There are neither prospective data nor agreement on the optimal routine follow-up procedures in patients treated for soft tissue sarcoma of the limb. METHODS: Data on 174 consecutive patients with a soft tissue sarcoma of the limb undergoing follow-up by oncologists at a single centre from 2003 to 2009 were included in this analysis. The rate and site of recurrence and mode of detection were analysed. Outcome of the patients was assessed. RESULTS: Eighty-two patients (47%) experienced relapse of any type. Isolated local recurrence occurred in 26 patients and local relapse with synchronous pulmonary metastases in five patients. Local recurrences were detected clinically in 30 of these 31 patients; magnetic resonance imaging identified only one local recurrence. Twenty-eight patients developed isolated lung metastases; in nine patients these were amenable to resections, seven of whom are currently free of disease after treatment. Lung metastases were detected by chest x-ray (CXR) in 19 patients, computed tomography scanning in 3 patients, and clinically in 11 patients. Twenty-three patients developed non-pulmonary metastases. More than 80% of relapses occurred in the first 2 years of follow-up; however, later recurrences were also observed. CONCLUSIONS: Routine follow-up CXR can detect lung metastases suitable for surgical resection, although the optimal interval of imaging has yet to be defined. Local relapse is almost always detected by patients or physicians, and routine scanning of the primary site is of doubtful benefit. Patient and physician education to detect local relapse may be helpful. Prospective evaluation of follow-up is recommended