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ABSTRACT A thorough understanding of cell response to combined culture configuration and mechanical cues is of paramount importance in vascular tissue engineering applications. Herein, we investigated and compared the response of vascular smooth muscle cells (vSMCs) cultured in different culture environments (2D cell monolayers and 3D cellularized collagen-based gels) in combination with mechanical stimulation (7% uniaxial cyclic strain, 1 Hz) for 2 and 5 days. When cyclic strain was applied, two different responses, in terms of cell orientation and expression of contractile-phenotype proteins, were observed in 2D and 3D models. Specifically, in 2D configuration, cyclic strain caused ∼50% of cell population to align nearly perpendicular (80-90 degrees) to the strain direction, while not influencing the contractile-phenotype protein expression, as compared to the 2D static controls. Conversely, the application of uniaxial strain to 3D constructs induced a ∼60% cell alignment almost parallel (0-10 degrees) to the strain direction. Moreover, 3D mechanical stimulation applied for 5 days induced a twofold increase of SM α-actin level and a 14-fold increase of calponin expression as compared to 3D static controls. Altogether these findings provide a new insight into the potential to drive cell behavior by modulating the extracellular matrix and the biomechanical environment. Biotechnol. Bioeng. 2016;113: 2254-2263. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective To determine whether neuropsychological measures differ between patients with idiopathic Parkinson's disease (PD) who acquire dementia within 10 years of disease onset versus those who acquire dementia later in the disease course, using data from the longitudinal Sydney Multicentre Study of PD. Methods The Sydney Multicentre Study of PD is a cohort of 149 community-living de novo patients with idiopathic PD studied over a 20-year period. Detailed clinical and neuropsychological tests were administered at baseline and at 3, 5, 10, 15 and 20 years, and the dementia status was assessed at each time point. For the present study, the pattern of longitudinal neuropsychological measures was compared between PD patients with the onset of dementia in the middle (5e10 years, mid-stage PD dementia, N=20) or late (>10 years, late-stage PD dementia, N=10) disease stages using analysis of variance and multiple linear regression modelling, and the relationship between age and dementia onset assessed using survival statistics. Results Mid-stage PD dementia patients were differentiated from late-stage PD dementia patients by having greater deficits in vocabulary skills prior to and at dementia onset. The pattern of cognitive deficits following dementia onset are similar, and there is no difference in the age of dementia onset between the different PD groups. Conclusions These data suggest that the evolution of dementia within PD occurs at around 70 years of age, regardless of the time of PD onset, and affects cognitive domains in a similar way, although patients with earlieronset PD have a preserved linguistic ability prior to dementia onset. [ABSTRACT FROM AUTHOR]

We performed a retrospective review of cases of human immunodeficiency virus-associated progressive multifocal leucoencephalopathy in four hospitals (three in Australia and one in Hong Kong) between 1987 and 2003 in order to describe the local experience with this disease and to evaluate parameters impacting upon survival. Eighty-seven cases were identified and demographic details, baseline parameters and treatment methods and response were described. Survival was substantially increased in the post-highly active antiretroviral therapy (HAART) era with a median survival increase from 14 to 64 weeks. On multivariate analysis, variables associated with prolonged survival included a CD4 count of >100 cells/ μl at diagnosis and the use of HAART post-diagnosis, with no significant additional advantage from the use of neuroactive antiretrovirals. [ABSTRACT FROM AUTHOR]

In the traditional use of design of experiments (DOE), an experiment is carried out where the input factors are varied according to a systematic plan. The data are then analysed in the usual way, but not before all of the required response values are available. A procedure called 'Reverse DOE' is presented for retrospectively selecting and fitting a fractional factorial design in situations where observed data are already available. This takes into account a set of factor effects that need to be estimated and also handles the possibility that certain treatment conditions may not be available or observed. A worked example from the steel industry is presented to illustrate the procedure. The procedure is expected to be useful in the early stages of experimentation and discovery, especially for factor screening purposes. [ABSTRACT FROM AUTHOR]

Objective: To investigate arousal from sleep in infants before and after triple antigen immunization (DTP).Methodology: Arousal thresholds were determined in both active sleep (AS) and quiet sleep (QS) the day before and the day following the first DTP immunisation in 14 infants. Arousal was induced using a pulsatile puff of air delivered alternately to the nostrils of the infant.Results: Arousal threshold was significantly higher in QS compared to AS in both studies (P < 0.001). Mean arousal threshold in the pre immunization study was not different from that in the post immunization study in either sleep state. Core temperature and heart rate measured at the time of stimulus delivery were both significantly elevated in the post immunisation study (P < 0.001). Sleep duration and number of awakenings from sleep were unaffected by immunization.Conclusion: The first triple antigen immunisation has no effect on arousal from sleep in either AS or QS in this group of infants. [ABSTRACT FROM AUTHOR]

The article investigates the behavior of barium in the terrestrial ecosystem, in Central Virginia. The study presented hypotheses which include high bioaccumulation and bioconcentration factors, that barium has low toxicity which allows different receptors for accumulation without adverse effects, and, that barium is being released from a persistent source that would provide chronic exposure required to allow steady accumulation in terrestrial receptors. Results of the study revealed that in animals, chronic exposure to the element will lead to disturbance in the cardiovascular function and regulation and prolonged muscle contraction. Results also revealed that barium has low assimilation frequency, low bioaccumulation factors for receptors, which may cause adverse effects to wildlife.

A letter to the editor is presented on the clinical and imaging features of a Chinese-speaking man with semantic dementia.

Background The homeostatic control of emotions and metabolism is disturbed early in Huntington's disease (HD), which may be due to changes in hypothalamic function. Previous studies have identified a loss of orexin (hypocretin) neurons in the lateral hypothalamus in HD patients. There has been only limited assessment of other hypothalamic regions in HD. Aims The aim of the study was to assess the neuropeptide expressing hypothalamic neurons known to regulate metabolism and emotion in HD patients compared with healthy controls. Methods Hypothalamic serial sections from HD (n=6) and controls (n=4) cases were processed for cresyl violet, Luxol fast blue and immunohistochemistry. Quantification of total cell numbers was performed using unbiased stereology. Results Substantial differences exist in peptide expression of different neuronal populations in HD hypothalamus compared with controls. In addition to loss of orexin expressing neurons, both oxytocin and vasopressin expressing neurons were decreased. The number of cocaine and amphetamine regulated transcript (CART) expressing neurons was increased. The increased expression of CART in the hypothalamus is consistent with a previous study showing increased CART levels in CSF from HD patients. There was no difference in the numbers of neuropeptide Y expressing neurons. Conclusions These results show significant and specific alterations in the peptide expression of hypothalamic neurons known to regulate metabolism and emotion. These changes may be important for the development of the psychiatric symptoms and metabolic disturbances characterising HD, and may provide potential targets for therapeutic interventions. [ABSTRACT FROM PUBLISHER]

Background: Self-awareness of Huntington''s disease (HD) onset has rarely been studied in a premanifest cohort, but poor recognition and reporting of symptoms could lead to a delay in diagnosis and, with that, appropriate management/care and notification of family regarding their HD risk. Moreover, poor awareness of first onset of HD could result in collecting inaccurate information about the disease; treatment, if available, could be delayed; and reports of drug effectiveness, inaccurate. Also, some patients, once they have undergone testing for the HD mutation, become overly “aware” of possible symptoms. We investigated this in a cross-sectional sample of 615 participants attending their third visit in the Predict-HD study. Results: Of these, 79 (13%) were recently diagnosed with manifest HD. However, more than a third of those diagnosed did not acknowledge any disease symptoms, despite showing similar signs of decline in terms of UHDRS Motor and TFC scores, psychomotor performance (Tapper), and companion ratings of frontal/executive dysfunction. Participants who reported not noticing any symptoms of HD also reported significantly less depression and fewer behavioral difficulties (indicative of frontal/executive dysfunction), consistent with poor insight. For participants who were classified as premanifest, those reporting symptoms of HD tended to have more cognitive, psychiatric, and other symptoms (compared to motor symptoms, which were most common in the recently diagnosed group). In the premanifest group, participants reporting symptoms had significantly higher ratings of depression and frontal/executive dysfunction (compared to those who were ‘symptom-fee''), rating themselves similarly to the group with HD diagnosis, despite fewer signs of disease (i.e., better Motor, TFC, and Tapper scores) and longer estimated time to disease onset. Conclusions: These results suggest that poor awareness of HD is a substantial problem in the premanifest or early stages of HD, but further research is needed to examine the predictors and implications of under/over reporting of HD symptomatology. [Copyright &y& Elsevier]