Peripersonal space boundaries around the lower limbs.

Neurophysiological investigations in non-human primates have shown that bi- and tri-modal fronto-parietal neurons exist that respond to touch on the body and visual (and/or auditory) stimuli near the body. The receptive fields of these neurons extend into space around the body, producing a zone wherein multisensory information is readily integrated. This space around the body, known as peripersonal space (PPS), has also been investigated behaviourally in humans. Some studies have focused on how far into depth the spatial boundaries of PPS extend. Most of these investigations have focused on the upper body (e.g., hands, face, trunk), while little is known about the size of PPS for the lower body (i.e. legs and feet). Thus, the aim of the current study was to delineate a PPS boundary around the lower limbs in healthy participants using a multisensory interaction task. Participants made speeded responses to the presence of vibrations applied to the toes while a task-irrelevant visual stimulus approached towards (Experiment 1) or receded from (Experiment 2) the feet. Participants responded significantly faster to tactile stimuli when the visual stimulus was within approximately 73 cm from the feet, but only when it approached (and not receded from) the legs. This is the first study, to our knowledge, to outline the size of PPS for the lower limbs. These findings could provide insight into the mechanisms underlying multisensory integration in the lower limbs, and add to the current body of knowledge on PPS representations.

Body ownership and the absence of touch: approaching the rubber hand inside and outside peri-hand space.

It is widely accepted that the integration of visual and tactile information is a necessity to induce ownership over a rubber hand. This idea has recently been challenged by Ferri et al. (Proc R Soc B 280:1-7, 2013), as they found that sense of ownership was evident by mere expectation of touch. In our study, we aimed to further investigate this finding, by studying whether the mere potential for touch yields a sense of ownership similar in magnitude to that resulting from actually being touched. We conducted two experiments. In the first experiment, our set-up was the classical horizontal set-up (similar to Botvinick and Cohen, Nature 391:756, 1998). Sixty-three individuals were included and performed the classical conditions (synchronous, asynchronous), an approached but not touched (potential for touch), and a 'visual only' condition. In the second experiment, we controlled for differences between the current set-up and the vertical set-up used by Ferri et al. (Proc R Soc B 280:1-7, 2013). Fifteen individuals were included and performed a synchronous and various approaching conditions [i.e., vertical approach, horizontal approach, and a control approach (no hands)]. In our first experiment, we found that approaching the rubber hand neither induced a larger proprioceptive drift nor a stronger subjective sense of ownership than asynchronous stimulation did. Generally, our participants gained most sense of ownership in the synchronous condition, followed by the visual only condition. When using a vertical set-up (second experiment), we confirmed previous suggestions that tactile expectation was able to induce embodiment over a foreign hand, similar in magnitude to actual touch, but only when the real and rubber hand were aligned on the vertical axis, thus along the trajectory of the approaching stimulus. These results indicate that our brain uses bottom-up sensory information, as well as top-down predictions for building a representation of our body.

Fibroid vascularisation assessed with three-dimensional power Doppler ultrasound is a predictor for uterine fibroid growth: a prospective cohort study.

OBJECTIVE: To analyse fibroid vascularisation measured with three-dimensional (3D) power Doppler in relation to absolute fibroid volume change during 12 months of follow up and in relation to fibroid growth rate per year. DESIGN: A prospective cohort study was performed between March 2012 and March 2014. SETTING: Outpatient clinic of the VU medical centre, Amsterdam. POPULATION OR SAMPLE: All premenopausal women diagnosed with a maximum of two fibroids with expectant management were consecutively included. METHODS: Three-dimensional ultrasound including power Doppler was performed at baseline, 3, 6 and 12 months. Volume and vascular parameters were calculated using VOCAL software. MAIN OUTCOME MEASURES: The relationship between vascular index (VI) at baseline and fibroid volume over time was analysed using linear mixed model analyses for repeated measurements. Second, the relationship between VI at baseline and fibroid growth rate per year was calculated using linear regression analyses. Analyses were adjusted for possible confounders. RESULTS: In all, 66 women (mean age 42 years) completed 12 months of follow up without treatment. Baseline fibroid vascularisation (VI) measured with 3D power Doppler is correlated with fibroid volume at 12 months (P = 0.02 ). An increase of 1% in VI at baseline was associated with a 7.00-cm3 larger fibroid volume at 12 months. Furthermore, vascularisation was also associated with fibroid growth rate per year (P = 0.04). CONCLUSION: In women with uterine fibroids without therapy, baseline vascularisation (VI) measured with 3D power Doppler is correlated with absolute fibroid volume change at 12 months and with fibroid growth rate per year. TWEETABLE ABSTRACT: Fibroid vascularisation correlates with absolute fibroid volume change and fibroid growth rate per year.

Functionality appreciation is associated with improvements in positive and negative body image in patients with an eating disorder and following recovery.

BACKGROUND: Research on body image in eating disorders has predominantly focused on negative body image, only recently shifting to positive body image. Findings suggest that enhancing positive body image can, amongst other things, serve as a protective mechanism against (re)developing a negative body image. One suggested way of enhancing positive body image is to focus on enhancing body functionality appreciation. Although studies show promising effects, this research is mainly conducted in non-clinical samples. METHODS: The current study investigated the levels of positive and negative body image in an online community sample of patients with an eating disorder (PAT, n = 227), patients recovered from an eating disorder (REC, n = 102) and controls (HC, n = 175) (self-reported diagnosis, not confirmed). In addition, we tested whether body functionality appreciation was associated with appearance dissatisfaction (negative body image) and body appreciation (positive body image). RESULTS: REC showed similar results to controls to most of the body image measures except for how much importance one places on their appearance (no different between REC and PAT), and how satisfied one is with certain body parts. For this measure, REC scored in-between PAT and HC. We further found functionality appreciation to be significantly associated with of both positive and negative body image, except for appearance evaluation in patients with an eating disorder. CONCLUSIONS: This study showed a positive association between body functionality appreciation and positive body image and a negative association between body functionality appreciation and negative body image. Further research is required to investigate the effectiveness of interventions targeting body functionality appreciation in clinical settings.

People with an eating disorder often suffer from a negative body image. This negative body image has been found to be hard to treat. Recently researchers started to not only look at ways to decrease negative body image but also enhance positive body image. It has been found that it is beneficial for people with a negative body image to learn to focus on appreciating the functions of the body (body functionality appreciation), as this leads to a more positive body image. However, this research was done on people without an eating disorder. In this questionnaire study, we looked at whether there is a relationship between body functionality appreciation and body image in patients with a (self-reported) eating disorder diagnosis and those who are recovered from an eating disorder. We found that functionality appreciation is associated with increased positive body image and decreased negative body image in all groups. Further studies should investigate the effectiveness of clinical interventions that focus on body functionality appreciation to enhance body image.

Affective touch perception and longing for touch during the COVID-19 pandemic.

Interpersonal touch and affective touch play a crucial role in social interactions and have a positive influence on mental health. The social distancing regulations implemented during the COVID-19 pandemic have reduced the ability to engage in interpersonal touch. This could cause longing for touch, and it might subsequently alter the way in which affective touch is perceived. To investigate this, we conducted an online survey and included 1982 participants, which contained questions regarding the COVID-19 regulations, longing for touch, and the perceived pleasantness of affective and non-affective touch. Results showed that participants reported feelings of longing for touch. This significantly increased with the duration and severity of the COVID-19 regulations. In addition, participants who experienced more longing for touch rated videos of affective and non-affective touch as more pleasant. Current results provide insight in the impact of sudden and prolonged COVID-19 regulations and show that increasing the duration and severity of these regulations is associated with a higher desire for touch, which is associated with increased perceived pleasantness of observing touch.

Blunt and Penetrating Liver Trauma have Similar Outcomes in the Modern Era.

BACKGROUND: The trend in liver trauma management has progressively become increasingly conservative. However, a vast majority of literature focuses heavily on the management of blunt trauma. This study reviews the management of hepatic trauma at a major trauma center in a developing world setting, in order to compare blunt and penetrating liver trauma and to define current management algorithms and protocols. METHODS: All patients who sustained liver trauma between 2012 to 2018 were identified in the Hybrid Electronic Medical Registry and extracted for further analysis. RESULTS: A total of 808 patients with hepatic trauma were managed by our trauma center. There were 658 males and 150 females. The mean age was 30 years (standard deviation 13.3). A total of 68 patients died (8.2%) and a total of 290 (35%) patients required intensive care unit admission. The mean presenting shock index was 0.806 (standard deviation 0.67-1.0), the median Injury Severity Score was 18 (interquartile range 10-25) and the mean Revised Trauma Score was 12 (standard deviation 11-12). There were 367 penetrating and 441 blunt liver injuries. The age distribution was similar in both groups. There were significantly less females in the penetrating group. The shock index and the Injury Severity Score on presentation were significantly worse in the blunt group, respectively: 0.891 (standard deviation 0.31) versus 0.845 (standard deviation 0.69) (p < 0.001) and score 21 (interquartile range 13-27) versus 16 (interquartile range 9-20) (p < 0.01). The opposite applied to the Revised Trauma Score of 11.75 (standard deviation 0.74) versus 11.19 (standard deviation 1.3) (p < 0.001). There were significantly more associated intra-abdominal injuries in the penetrating group than the blunt group, in particular that of hollow organs, and 84% of patients with a penetrating injury underwent a laparotomy while only 33% of the blunt injuries underwent a laparotomy. The mortality rate was comparable between both groups. CONCLUSION: Hepatic trauma is still associated with a high morbidity rate, although there have been dramatic improvements in mortality rates over the last three decades. The mortality rates for blunt and penetrating liver trauma are now similar. Non-operative management is feasible for over two-thirds of blunt injuries and for just under 20% of penetrating injuries.

Fibroid vascularisation assessed with 3D Power Doppler as predictor for fibroid related symptoms and quality of life; a pilot study.

BACKGROUND: Uterine fibroids present differently, from well vascularised up to calcified, with some causing heavy menstrual bleeding (HMB). OBJECTIVES: To investigate the association between fibroid vascularisation and HMB, other fibroid related symptoms and quality of life (QOL). MATERIALS AND METHODS: A single centre pilot study was carried out in the Netherlands. Women with a maximum of two fibroids who chose expectant management were included. 3D sonography including power doppler was performed at baseline and at 3, 6 and 12 months follow up. Women were asked to complete the Pictorial Blood Assessment Chart (PBAC) and Uterine Fibroid Symptom and Quality of Life (UFS-QOL) questionnaires at every visit. MAIN OUTCOME MEASURE: Main outcome measure: The association between fibroid vascularisation and HMB. RESULTS: 53 women were included in the study. Baseline fibroid vascularisation, measured as vascular index (VI) is associated with PBAC score; a 1% higher VI at baseline leads to an 11 point increase in PBAC score over time (RC 10.99, p=0.05, 95% CI -0.15 - 22.12). After correction for the baseline variables ethnicity and fibroid type the association becomes stronger (P<0.05). Fibroid volume at baseline and HMB are also associated: a 1 cm3 larger fibroid leads to 0.6 points increase in PBAC score over time (RC 0.56, p=0.03, 95% CI 0.05 - 1.07). CONCLUSIONS: Conclusions: This study highlights that both fibroid vascularisation and fibroid volume may be associated with an increase in menstrual blood loss, other fibroid related symptoms and QOL over time. WHAT IS NEW?: What is new? We used 3D power doppler to predict symptomatic fibroids.

The correlation between full moon and admission volume for penetrating injuries at a major trauma centre in South Africa.

BACKGROUND: The possible effect of full moon on admission volume of trauma centres is a well-mentioned phenomenon that has been perpetuated worldwide. We aimed to review the correlation between full moon and admission volume and to interrogate any possible relationship on admission for penetrating trauma. METHODS: A retrospective study from 2012 to 2018 at Pietermaritzburg Metropolitan Trauma Service (PMTS), South Africa. RESULTS: A total of 8 722 patients were admitted. Eighty-three per cent (7 242/8 722) were male and the mean age was 29 years. The total number of days during the study period was 1 953, 66 of which were 'full moon' (FM) days and 1 887 were 'non-full moon' (NFM) days. There was no significant difference between gender or age distribution. The mean number of admissions per day on FM days compared with NFM days was not significant (4.1 vs 4.5, p = 0.583). A total of 3 332 patients with penetrating trauma were admitted. This constituted 42% (113/271) of admission on FM days and 38% (3 219) on NFM days, which is not statistically significant (p = 0.229). Subgroup analysis did not demonstrate any significant difference between the number of stab wounds - 28% (77/113) vs 25% (2 124/3 219) - or gunshot wounds - 13% (16/113) vs 12% (990/3 219) - between FM and NFM days. CONCLUSION: The correlation between full moon and trauma admission is unfound in our setting. The perpetuating notion that 'it must be full moon tonight' is likely to be an urban myth with no scientific evidence for such a claim.

Towards a structural characterization of charge-driven polymer micelles.

Light scattering and small-angle neutron scattering experiments were performed on comicelles of several combinations of oppositely charged (block co)polymers in aqueous solutions. Fundamental differences between the internal structure of this novel type of micelle --termed complex coacervate core micelle (C3Ms), polyion complex (PIC) micelle, block ionomer complex (BIC), or interpolyelectrolyte complex (IPEC)-- and its traditional counterpart, i.e., a micelle formed via self-assembly of polymeric amphiphiles, give rise to differences in scaling behaviour. Indeed, the observed dependencies of micellar size and aggregation number on corona block length, N (corona) , are inconsistent with scaling predictions developed for polymeric micelles in the star-like and crew-cut regime. Generic C3M characteristics, such as the relatively high core solvent fraction, the low core-corona interfacial tension, and the high solubility of the coronal chains, are causing the deviations. A recently proposed scaling theory for the cross-over regime, as well as a primitive first-order self-consistent field (SCF) theory for obligatory co-assembly, follow our data more closely.

Complex coacervate core micro-emulsions.

Complex coacervate core micelles form in aqueous solutions from poly(acrylic acid)-block-poly(acrylamide) (PAAxPAAmy, x and y denote degree of polymerization) and poly(N,N-dimethyl aminoethyl methacrylate) (PDMAEMA150) around the stoichiometric charge ratio of the two components. The hydrodynamic radius, Rh, can be increased by adding oppositely charged homopolyelectrolytes, PAA140 and PDMAEMA150, at the stoichiometric charge ratio. Mixing the components in NaNO3 gives particles in highly aggregated metastable states, whose Rh remain unchanged (less than 5% deviation) for at least 1 month. The Rh increases more strongly with increasing addition of oppositely charged homopolyelectrolytes than is predicted by a geometrical packing model, which relates surface and volume of the particles. Preparation in a phosphate buffer - known to weaken the electrostatic interactions between PAA and PDMAEMA - yields swollen particles called complex coacervate core micro-emulsions (C3-µEs) whose Rh increase is close to that predicted by the model. These are believed to be in the stable state (lowest free energy). A two-regime increase in Rh is observed, which is attributed to a transition from more star-like to crew-cut-like, as shown by self-consistent field calculations. Varying the length of the neutral and polyelectrolyte block in electrophoretic mobility measurements shows that for long neutral blocks (PAA26PAAm405 and PAA39PAAm381) the ζ-potential is nearly zero. For shorter neutral blocks the ζ-potential is around -10 mV. This shows that the C3-µEs have excess charge, which can be almost completely screened by long enough neutral blocks.

Touch screen computer-assisted health-related quality of life and distress data collection in head and neck cancer patients.

Touch screen computer-assisted health-related quality of life data collection in head and neck cancer patients is feasible. Touch screen computer-assisted health-related quality of life data collection can be used for scientific documentation as well as in clinical setting. Patients are willing to complete the questionnaire on a touch-screen and find the equipment easy to use. Compliance needs improvement by instructing clinicians and nurses and a better alert system.

On the stability of (highly aggregated) polyelectrolyte complexes containing a charged-block-neutral diblock copolymer.

Using light scattering and cryogenic transmission electron microscopy, we show that highly aggregated polyelectrolyte complexes (HAPECs) composed of poly([4-(2-aminoethylthio)butylene] hydrochloride)49-block-poly(ethylene oxide)212 and poly(acrylic acid) (PAA) of varying lengths (140, 160, and 2000 monomeric units) are metastable or unstable if the method of preparation is direct mixing of two solutions containing the oppositely charged components. The stability of the resulting HAPECs decreases with decreasing neutral-block content and with increasing deviation from 1:1 mixing (expressed in number of chargeable groups) of the oppositely charged polyelectrolytes, most probably for electrostatic reasons. The difference between the metastable and stable states, obtained with pH titrations, increases with increasing PAA length and increasing pH mismatch between the two solutions with the oppositely charged components.

Bioflocculation of mesophilic and thermophilic activated sludge.

Thermophilic activated sludge treatment is often hampered by a turbid effluent. Reasons for this phenomenon are so far unknown. Here, the hypothesis of the temperature dependency of the hydrophobic interaction as a possible cause for diminished thermophilic activated sludge bioflocculation was tested. Adsorption of wastewater colloidal particles was monitored on different flat surfaces as a function of temperature. Adsorption on a hydrophobic surface varied with temperature between 20 and 60 degrees C and no upward or downward trend could be observed. This makes the hydrophobic interaction hypothesis unlikely in explaining the differences in mesophilic and thermophilic activated sludge bioflocculation. Both mesophilic and thermophilic biomass did not flocculate with wastewater colloidal particles under anaerobic conditions. Only in the presence of oxygen, with biologically active bacteria, the differences in bioflocculation behavior became evident. Bioflocculation was shown only to occur with the combination of wastewater and viable mesophilic biomass at 30 degrees C, in the presence of oxygen. Bioflocculation did not occur in case the biomass was inactivated or when oxygen was absent. Thermophilic activated sludge hardly showed any bioflocculation, also under mesophilic conditions. Despite the differences in bioflocculation behavior, sludge hydrophobicity and sludge zetapotentials were almost similar. Theoretical calculations using the DLVO (Derjaguin, Landau, Verweij and Overbeek) theory showed that flocculation is unlikely in all cases due to long-range electrostatic forces. These calculations, combined with the fact that bioflocculation actually did occur at 30 degrees C and the unlikelyness of the hydrophobic interaction, point in the direction of bacterial exo-polymers governing bridging flocculation. Polymer interactions are not included in the DLVO theory and may vary as a function of temperature.

[Palliative sedation, the sympathetic alternative for euthanasia?]. / Palliatieve sedatie, het sympathieke alternatiefvoor euthanasie?

Palliative sedation is given to relieve refractory discomfort (pain, shortness of breath, agitation) during the phase when life expectancy is estimated to be a week or less. It is a medical intervention which, although not expressly meant to shorten life, may well do so. There is an inherent uncertainty here which is the cause of considerable ethical unease. Figures show that in a limited number of cases palliative sedation is actually applied with the intention to hasten death. It may well be impossible to rid ourselves ofthis uncertainty conclusively.

Neurocognitive dysfunction after coronary artery bypass surgery: a systematic review.

OBJECTIVE: Substantial, albeit scattered, evidence suggests that coronary artery bypass grafting may impair cognitive function. As methods and definitions differ greatly across studies, the reported incidence of cognitive decline after coronary bypass surgery varies widely as well. The aim of the present study was to systematically review those studies on cognitive decline that are relatively comparable and meet with certain quality criteria. METHODS: Four electronic databases and the references of several abstract books and earlier reviews were used to identify relevant literature. Stringent criteria, based in part on the 1994 consensus meeting on assessment of neurobehavioral outcomes after cardiac surgery, were used to assess the studies that were found. In total, 256 different titles were found, of which 23 met with the formulated selection criteria. RESULTS: Twelve cohort studies and eleven intervention studies were evaluated. A pooled analysis of six highly comparable studies yielded a proportion of 22.5% (95% confidence interval, 18.7%-26.4%) of patients with a cognitive deficit (a decrease of at least 1 standard deviation in at least two of nine or ten tests) 2 months after the operation. CONCLUSIONS: Neurocognitive dysfunction is a frequently occurring complication of coronary artery bypass grafting. The etiologic contribution of cardiopulmonary bypass to this complication will remain unclear until a randomized trial that directly compares off-pump and on-pump bypass surgery is carried out.

Biodegradability and change of physical characteristics of particles during anaerobic digestion of domestic sewage.

At the high-rate anaerobic treatment of domestic sewage, both biological and physical processes play an important role. Therefore, the anaerobic biodegradability of raw, paper-filtered and membrane-filtered sewage and black water has been investigated in batch experiments. Additionally, the effect of anaerobic digestion on physical characteristics, like particle size, surface tension and zeta-potential, of the present particles is studied. The biodegradability of domestic sewage and black water at 30 degrees C is almost similar (71-74%). Moreover, a high methanogenesis of the colloidal fraction in domestic sewage (86 +/- 3%) is achieved, showing that the low removal of colloidal particles in continuous high-rate anaerobic reactors is due to low physical removal rather than biodegradability. The lowest biodegradability is demonstrated for the dissolved fraction (62%). The results show that after anaerobic digestion the average radius of particles with diameter < 4.4 and < 0.45 microns increased for domestic sewage, while it decreased for black water. Part of the surface-active components in domestic sewage is not biodegraded during anaerobic batch digestion, as indicated by the development of the surface tension. The negative zeta-potential of all particles hardly changes during digestion, showing that colloidal interactions were not affected by anaerobic digestion.

Mixed adsorption of poly(vinylpyrrolidone) and sodium dodecylbenzenesulfonate on kaolinite.

The mixed adsorption of the nonionic polymer poly(vinylpyrrolidone) (PVP) and the anionic surfactant sodium dodecylbenzenesulfonate (SDBS) on kaolinite has been studied. Both components adsorb from their mixture onto the clay mineral. The overall adsorption process is sensitive to the pH, the electrolyte concentration, and the amounts of polymer and surfactant. Interpretation of the experimental data addresses also the patchwise heterogeneous nature of the clay surface. In the absence of PVP, SDBS adsorbs on kaolinite by electrostatic and hydrophobic interactions. However, when PVP is present, surfactant adsorption at 10(-2) M NaCl is mainly driven by charge compensation of the edges. The adsorption of PVP from the mixture shows similar behavior under different conditions. Three regions can be distinguished based on the changing charge of polymer-surfactant complexes in solutions with increasing SDBS concentration. At low surfactant content, PVP adsorbs by hydrogen bonding and hydrophobic interactions, whereas electrostatic interactions dominate at higher surfactant concentrations. Over the entire surfactant concentration range, polymer-surfactant aggregates are present at the edges. The composition of these surface complexes differs from that in solution and is controlled by the surface charge.

[Letters of condolence to the relatives of patients]. / Condoleancebrieven aan nabestaanden van patiënten.

Most people who die in the Netherlands receive medical care during the final stage of their life. Since the 19th century, when a sombre prognosis was often the only medical intervention available, sophisticated diagnostic procedures and curative victories have forced elementary bedside manners into retreat. However, modern medicine is rediscovering its boundaries; the inevitability of death and the human tragedy of dying. The renewed interest in letters of condolence from doctors to the family of their deceased patients is an example of this. These letters provide the physician with an opportunity for worthy and effective behaviour under trying circumstances.

[Percutaneous endoscopic gastrostomy catheter: a trap without escape?]. / PEG-sonde: fuik zonder ontsnappingsweg?

Three patients, a 76-year old man with Parkinson's disease and two women aged 81 and 80 years, both of whom had experienced a stroke, were transferred from a hospital to a nursing home following the insertion of a percutaneous endoscopic gastrostomy (PEG) catheter. The worldwide accepted indication for the insertion of a PEG catheter is: the existence of serious swallowing disorders which are expected to last for more than 2-4 weeks and are mostly connected with a neurological disorder with an uncertain prognosis. However, this procedure may lead to a fairly common adverse effect, although never acknowledged as such: the unintended prolonging of a patient's suffering. This was also the case for the patients described. Eventually in the case of the first two patients, who were completely passive and incontinent for both urine and faeces, the catheter was removed once it had been established (in discussions with those responsible for treatment and the family) that it no longer fulfilled its purpose as a medical treatment. The patients died under adequate sedation. In the case of the third patient, those responsible for the treatment were unsure about the unfavourable prognosis and the absence of a quality of life; she later died from an untreated pneumonia. In order to reduce the frequency with which these serious consequences occur, it is suggested that the insertion of a PEG catheter should be characterised as a medical procedure the purpose of which should be clearly stated. Whether or not this purpose has been attained can be evaluated at given points in time so that the treatment can either be continued, or withdrawn.