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To review new putative mechanisms involved in the pathophysiology of a disturbed energy balance in cancer cachexia, which can lead to novel targets for clinical cachexia management. In the context of rapid developments in tumour treatment with potential systemic consequences, this article reviews recent data on energy requirements. Furthermore, we focus on new insights in brown adipose tissue (BAT) activity and reward processing in the brain in relation to the cachexia process.Nearly no new data have been published on energy requirements of cancer patients in the light of comprehensive new therapies in oncology. New developments, such as the introduction of staging with 18F-fluorodeoxyglucose PET-computed tomography scanning, led to the observation that BAT activation may contribute to impaired energy balance in cancer cachexia. Animal and human data to date provide an indication that BAT activation indeed occurs, but its quantitative impact on the degree of cachexia is controversial. The peripheral and central nervous system is known to influence satiation, with a possible role for impaired food reward processing in the brain. To date, there are limited confirmatory data, but this is an interesting new area to explore for better understanding and treating cancer-induced anorexia.The multimodal approach to counteract cancer cachexia should expand its targets to BAT and food reward processing in the brain.

In this study, the suitability of amide proton transfer (APT) imaging as a biomarker for the characterization of high intensity focused ultrasound (HIFU)-treated tumor tissue was assessed.APT imaging was performed on tumor-bearing mice before (n = 15), directly after (n = 15) and at 3 days (n = 8) after HIFU treatment. A control group (n = 7) of nontreated animals was scanned at the same time points. Histogram analysis of the tumor APT-weighted signal distributions was performed to assess HIFU-induced changes in the tumor APT contrast.Distinct regions of decreased APT-weighted signal were observed at both time points after HIFU treatment. Analysis of the tumor APT-weighted signal distribution showed a pronounced shift toward lower APT-weighted signal values after HIFU treatment. A significantly increased fraction of pixels with an APT-weighted signal value between -10 and -2% was observed both directly (0.37 ± 0.16) and at 3 days (0.49 ± 0.16) after HIFU treatment as compared to baseline (0.22 ± 0.16).The presented results show that APT imaging is sensitive to HIFU-induced changes in tumor tissue and may thus serve as a new biomarker for monitoring the response of tumor tissue to HIFU treatment.

Maximal L-glutamate/glycine-evoked currents were inhibited by ethanol in Xenopus laevis oocytes expressing recombinant heteromeric NMDA receptors consisting of NR1-NR2A, NR1-NR2B, and NR1-NR2C subunit combinations. Concentration-dependent inhibition was observed at ethanol concentrations of > or = 50 mM both in Ca(2+)-containing and Ca(2+)-deficient, Ba(2+)-containing Mg(2+)-free media. The NR1-NR2C channels were slightly less sensitive to ethanol inhibition than the other heteromeric channels in Ca(2+)-deficient, Ba(2+)-containing medium. The inhibition was unaffected by the clamping-voltage and by a mutation [NR1-NR2A(N595Q)] that prevents the Mg(2+)-blockade of the channels, indicating that the mechanism of action of ethanol differs from that of Mg2+. The results are consistent with the hypothesis that the NMDA receptor subtypes can mediate many behavioural actions of ethanol.

Of the ionotropic glutamatergic receptors, the NMDA receptor is clearly implicated in the acute and chronic effects of ethanol; however, the role of the AMPA receptor in mediating the effects of ethanol in vivo is as yet unclear. Using mice deficient in the AMPA receptor subunit GluR1 (GluR1-/- mice), we investigated whether the AMPA receptor had a significant role in mediating the effects of ethanol. GluR1-/- mice showed greater locomotor activity in a novel environment, but by the fifth day of repeated testing their activity was the same as that of wild-type mice. In contrast to their enhanced locomotor activity, on an accelerating rotarod GluR1-/- mice performed consistently worse than wild-types. With regard to the effects of ethanol on motor responses, GluR1-/- mice did not differ significantly from wild-type mice in ethanol's sedative or incoordinating effects. However, the GluR1-/- mice were insensitive to the hypothermic effects of a hypnotic dose of ethanol in contrast to wild-types; this effect was dissociable from the hypnotic effects of ethanol. Further, tolerance to ethanol developed equally for GluR1-/- mice versus wild-type mice. In terms of alcohol drinking behavior, compared to wild-types, GluR1-/- mice differed neither in the acquisition of voluntary ethanol consumption nor in stress-induced ethanol drinking, nor in the expression of an alcohol deprivation effect (ADE) which is used as a model of relapse-like drinking behavior. In summary, although the loss of a hypothermic effect of ethanol in GluR1-/- mice indicates a critical role for the AMPA receptors in this effect, the GluR1 subunit of the AMPA receptor does not seem to play a critical role in the etiology of alcohol dependence. However, changes observed in activity patterns may be related to the putative role of AMPA receptors in attention deficit hyperactivity disorder.

Various spinal cord stimulation (SCS) modes are used in the treatment of chronic neuropathic pain disorders. Conventional (Con) and Burst-SCS are hypothesized to exert analgesic effects through different stimulation-induced mechanisms. Preclinical electrophysiological findings suggest that stimulation intensity is correlated with the effectiveness of Burst-SCS. Therefore, we aimed to investigate the relation between amplitude (charge per second) and behavioral effects in a rat model of chronic neuropathic pain, for both Conventional Spinal Cord Stimulation (Con-SCS) and biphasic Burst-SCS.Animals (n = 12 rats) received a unilateral partial sciatic nerve ligation, after which they were implanted with quadripolar electrodes in the epidural space at thoracic level 13. Mechanical hypersensitivity was assessed using paw withdrawal thresholds (WTs) to von Frey monofilaments, at various SCS intensities (amplitudes) and multiple time points during 60 minutes of stimulation and 30 minutes post stimulation.Increasing amplitude was shown to improve the efficacy of Con-SCS, whereas the efficacy of Burst-SCS showed a non-monotonic relation with amplitude. Con-SCS at 66% MT (n = 5) and Burst-SCS at 50% MT (n = 6) were found to be equally effective in normalizing mechanical hypersensitivity. However, in the assessed time period Burst-SCS required significantly more mean charge per second to do so (p < 0.01). When applied at comparable mean charge per second, Con-SCS resulted in a superior behavioral outcome (p < 0.01), compared with Burst-SCS.Biphasic Burst-SCS requires significantly more mean charge per second in order to achieve similar pain relief, as compared with Con-SCS, in an experimental model of chronic neuropathic pain.

In this work we address the problem of stimulating nervous tissue with the minimal necessary energy at reduced/minimal charge. Charge minimization is related to a valid safety concern (avoidance and reduction of stimulation-induced tissue and electrode damage). Energy minimization plays a role in battery-driven electrical or magnetic stimulation systems (increased lifetime, repetition rates, reduction of power requirements, thermal management). Extensive new theoretical results are derived by employing an optimal control theory framework. These results include derivation of the optimal electrical stimulation waveform for a mixed energy/charge minimization problem, derivation of the charge-balanced energy-minimal electrical stimulation waveform, solutions of a pure charge minimization problem with and without a constraint on the stimulation amplitude, and derivation of the energy-minimal magnetic stimulation waveform. Depending on the set stimulus pulse duration, energy and charge reductions of up to 80% are deemed possible. Results are verified in simulations with an active, mammalian-like nerve fiber model.

Although much is known about factors influencing short-term implementation, little is known about what factors are relevant for the long-term sustainment of innovations. In the Dutch National Quality Improvement Program for Palliative Care, innovations were implemented in 76 implementation projects.To give insight into the sustainment strategies used and factors facilitating and hindering sustainment.Online questionnaire with prestructured and open questions sent to the contact persons for 76 implementation projects, 2-6.5 years after the start.Information was gathered on 63 implementation projects (response 83%). Most projects took place in home care, general practices, and/or nursing homes. Sustainment was attained in 60% of the implementation projects. Six often applied strategies were statistically significantly related to sustainment: 1) realizing coherence between the innovation and the strategic policy of the organization; 2) arranging to have a specific professional responsible for the use of the innovation; 3) integrating the innovation into the organization's broader palliative care policy; 4) arranging accessibility of the innovation; 5) involving management in the implementation project; and 6) giving regular feedback about the implementation. In three-quarters of the projects, barriers and facilitators were encountered relating to characteristics of the care organizations, such as employee turnover and ratification of the project by the management.Applying the six strategies enhances sustainment. The organization plays a decisive role in the sustainment of innovations in palliative care. Engaging the management team in implementation projects from early onset is of utmost importance.

Calcium (Ca(2+)) has been characterized as one of the most ubiquitous, universal and versatile intracellular signaling molecules responsible for controlling numerous cellular processes. Ethanol-induced effects on Ca(2+) distribution and flux have been widely studied in vitro, showing that acute ethanol administration can modulate intracellular Ca(2+) concentrations in a dose dependent manner. In vivo, the relationship between Ca(2+) manipulation and the corresponding ethanol-induced behavioral effects have focused on Ca(2+) flux through voltage-gated Ca(2+) channels. The present study investigated the role of inward Ca(2+) currents in ethanol-induced psychomotor effects (stimulation and sedation) and ethanol intake. We studied the effects of the fast Ca(2+) chelator, BAPTA-AM, on ethanol-induced locomotor activity and the sedative effects of ethanol. Swiss (RjOrl) mice were pretreated with BAPTA-AM (0-10 mg/kg) 30 min before an ethanol (0-4 g/kg) challenge. Our results revealed that pretreatment with BAPTA-AM prevented locomotor stimulation produced by ethanol without altering basal locomotion. In contrast, BAPTA-AM reversed ethanol-induced hypnotic effects. In a second set of experiments, we investigated the effects of intracellular Ca(2+) chelation on ethanol intake. Following a drinking-in-the-dark methodology, male C57BL/6J mice were offered 20% v/v ethanol, tap water, or 0.1% sweetened water. The results of these experiments revealed that BAPTA-AM pretreatment (0-5 mg/kg) reduced ethanol consumption in a dose-dependent manner while leaving water and sweetened water intake unaffected. Our findings support the role of inward Ca(2+) currents in mediating different behavioral responses induced by ethanol. Our results are discussed together with data indicating that ethanol appears to be more sensitive to intracellular Ca(2+) manipulations than other psychoactive drugs.