Ca(v)2.3 channel function and Zn2+-induced modulation: potential mechanisms and (patho)physiological relevance

Voltage-gated calcium channels (VGCCs) are critical for Ca(2+)influx into all types of excitable cells, but their exact function is still poorly understood. Recent reconstruction of homology models for all human VGCCs at atomic resolution provides the opportunity for a structure-based discussion of VGCC function and novel insights into the mechanisms underlying Ca(2+)selective flux through these channels. In the present review, we use these data as a basis to examine the structure, function, and Zn2+-induced modulation of Ca(v)2.3 VGCCs, which mediate native R-type currents and belong to the most enigmatic members of the family. Their unique sensitivity to Zn(2+)and the existence of multiple mechanisms of Zn(2+)action strongly argue for a role of these channels in the modulatory action of endogenous loosely bound Zn2+, pools of which have been detected in a number of neuronal, endocrine, and reproductive tissues. Following a description of the different mechanisms by which Zn(2+)has been shown or is thought to alter the function of these channels, we discuss their potential (patho)physiological relevance, taking into account what is known about the magnitude and function of extracellular Zn(2+)signals in different tissues. While still far from complete, the picture that emerges is one where Ca(v)2.3 channel expression parallels the occurrence of loosely bound Zn(2+)pools in different tissues and where these channels may serve to translate physiological Zn(2+)signals into changes of electrical activity and/or intracellular Ca(2+)levels

Body mass index and leptin levels in serum and cerebrospinal fluid in relation to delayed cerebral ischemia and outcome after aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is associated with a high mortality rate and may leave surviving patients severely disabled. After the initial hemorrhage, clinical outcome is further compromised by the occurrence of delayed cerebral ischemia (DCI). Overweight and obesity have previously been associated with protective effects in the post-bleeding phase. The aim of this study was to assess the effects of a patient's body mass index (BMI) and leptin levels on the occurrence of DCI, DCI-related cerebral infarction, and clinical outcome. In total, 263 SAH patients were included of which leptin levels were assessed in 24 cases. BMI was recorded along disease severity documented by the Hunt and Hess and modified Fisher scales. The occurrence of clinical or functional DCI (neuromonitoring, CT Perfusion) was assessed. Long-term clinical outcome was documented after 12 months (extended Glasgow outcome scale). A total of 136 (51.7%) patients developed DCI of which 72 (27.4%) developed DCI-related cerebral infarctions. No association between BMI and DCI occurrence (P = .410) or better clinical outcome (P = .643) was identified. Early leptin concentration in serum (P = .258) and CSF (P = .159) showed no predictive value in identifying patients at risk of unfavorable outcomes. However, a significant increase of leptin levels in CSF occurred from 326.0 pg/ml IQR 171.9 prior to DCI development to 579.2 pg/ml IQR 211.9 during ongoing DCI (P = .049). In our data, no association between obesity and clinical outcome was detected. After DCI development, leptin levels in CSF increased either by an upsurge of active transport or disruption of the blood-CSF barrier. This trial has been registered at ClinicalTrials.gov (NCT02142166) as part of a larger-scale prospective data collection. BioSAB: https://clinicaltrials.gov/ct2/show/NCT02142166

Antagonists of ionotropic γ-aminobutyric acid receptors impair the NiCl2-mediated stimulation of the electroretinogram b-wave amplitude from the isolated superfused vertebrate retina

Numerous studies have demonstrated population genetic structuring in marine species, yet few have investigated the effect of vertical zonation on gene flow and population structure. Here we use three sympatric, closely related clinid species, Clinus cottoides, C. superciliosus and Muraenoclinus dorsalis, to test whether zonation on South African intertidal rocky shores affects phylogeographic patterns. We show that the high‐shore restricted species has reduced gene flow and considerably higher Fst values (Fst = 0.9) than the mid‐ and low‐shore species (Fst < 0.14). Additionally, we provide evidence for remarkably different demographic and evolutionary histories, ranging from extreme population bottlenecks to population persistence, which are probably linked to effective population size and habitat specialisation. This study further highlights the need for a multispecies approach to unravel the biological and evolutionary processes that drive extant population genetic patterns in marine species, as even closely related species with similar life histories show highly variable results.</p

Surgical Approaches in Psychiatry: A Survey of the World Literature on Psychosurgery

Brain surgery to promote behavioral or affective changes in humans remains one of the most controversial topics at the interface of medicine, psychiatry, neuroscience, and bioethics. Rapid expansion of neuropsychiatric deep brain stimulation has recently revived the field and careful appraisal of its 2 sides is warranted: namely, the promise to help severely devastated patients on the one hand and the dangers of premature application without appropriate justification on the other. Here, we reconstruct the vivid history of the field and examine its present status to delineate the progression from crude freehand operations into a multidisciplinary treatment of last resort. This goal is accomplished by a detailed reassessment of numerous case reports and small-scale open or controlled trials in their historical and social context. The different surgical approaches, their rationale, and their scientific merit are discussed in a manner comprehensible to readers lacking extensive knowledge of neurosurgery or psychiatry, yet with sufficient documentation to provide a useful resource for practitioners in the field and those wishing to pursue the topic further

Microbes: the good, the bad and the ugly. How society perceives them

Knowledge, Values and Practices (the KVP model) validates peoples’ conceptions and will be presented here within the educational system framework. The influences of scientists, the media, actors of the educational system and textbook authors on the school external didactic transposition (EDT) will be addressed. Particular emphasis will be given to pupils’ conceptions of microorganisms and how textbooks address these issues. It is well documented that eliciting what children already know and understand scientific concepts is important for achieving effective and significant learning. Examples of children’s conceptions about microorganisms before and after their first lessons on the subject will be shown. Children’s anthropomorphic ideas are very present, attributing human qualities to, for example, whether microorganisms are well- or evil-intentioned, can be assessed by children’s drawings and using terms such as ‘good’, ‘bad’ and ‘ugly’. Textbooks reinforcing the ‘bad’ and ‘ugly’ views are often conveyed within the biomedical model of health. Therefore, the ‘good’ view of microorganisms (e.g., delicious mushrooms, cheese and yogurt producers, soil and wastewater bioremediation…) is missing in the external didactic transposition, which is the result of an absence of the non-medical scientists’ influence in the education system. Finally, opportunities must be created for scientists, particularly in the non-biomedical field, to communicate with the education system and the general public, to emphasize the positive views of microorganisms