Purpose: The study aimed to understand the delirium experience of intensive care unit (ICU) patients. Methods: We performed a qualitative study using Colaizzi’s phenomenological method. Eleven patients, who experienced delirium according to the Confusion Assessment Method for ICU, participated after transferring to general wards from the ICU. Individual in-depth semi-structured interviews ranging from 30 minutes to 2 hours in length were conducted between November 2018 and August 2019. Results: Nine themes and four theme clusters emerged. The four theme clusters were: 1) “Overwhelmed by fear,” which describes the experience of a patient close to death and the feeling of difficulty in understanding disorganized thinking; 2) “Anxious about not understanding the situation,” which means that patients’ sense of time and space were disordered in the ICU; 3) “Being deserted,” which indicates the feeling of being separated from others and yourself; and 4) “Resistance to protect my dignity,” which indicates that the dignity and autonomy of an individual in the patient’s position at the ICU, are ignored. Conclusion Nursing interventions are needed that would enable patients to maintain orientation and self-esteem in the ICU. In addition, healthcare providers need to provide information about the unfamiliar environment in the ICU in advance.

Like neurons, astrocytes produce and release GABA to influence neuronal signaling. At the perforant path to dentate gyrus granule neuron synapse, GABA from astrocyte was found to be a strong inhibitory factor, which impairs synaptic transmission, synaptic plasticity and memory in Alzheimer's disease. Although astrocytic GABA is observed in many brain regions, its physiological role has not been clearly demonstrated yet. Here, we show that astrocytic GABA exerts disinhibitory action to dentate granule neurons by targeting GABA(B) receptors of GABAergic interneurons in wild-type mice. This disinhibitory effect is specific to a low intensity of electrical stimulation at perforant path fibers. Inversely in Alzheimer's disease model mice, astrocytic GABA targets GABA(A) receptors and exerts inhibitory action by reducing release probability of glutamatergic perforant path terminals. These results suggest that astrocytic GABA differentially modulates the signaling from cortical input to dentate gyrus under physiological and pathological conditions.
Alzheimer Disease* ; Animals ; Astrocytes ; Brain ; Dentate Gyrus* ; Electric Stimulation ; gamma-Aminobutyric Acid* ; Interneurons ; Memory ; Mice ; Neurons* ; Perforant Pathway* ; Plastics ; Receptors, GABA-A ; Synapses* ; Synaptic Transmission

Cephalotocin is a bioactivity-regulating peptide expressed in octopus (Octopus vulgaris). The peptide sequence of cephalotocin is very similar to the peptide sequence of mammalian vasopressin, and cephalotocin has been proposed to mainly activate arginine vasopressin 1b receptor (Avpr1b) in the brain. However, the effects of cephalotocin on mammalian behavior have not been studied. In the current study, cephalotocin significantly reduced both the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) recorded from not only cultured neuronal cells from postnatal Sprague–Dawley (SD) rats but also hippocampal slices from 4-week-old male C57BL/6 mice. Intraperitoneal (IP) injection did not affect the open field behaviors of C57BL/6 mice. Cephalotocin was directly infused into the hippocampus because the normalized Avpr1b staining intensity divided by the DAPI staining intensity indicated that Avpr1b expression tended to be high in the hippocampus. A hippocampal infusion of 1 mg/kg cephalotocin via an implanted cannula exerted an anti-stress effect, significantly reducing the immobility time in the tail suspension test (TST). The present results provide evidence that the effects of cephalotocin on the activity of hippocampal neurons are related to ameliorating stress, suggesting that cephalotocin may be developed as an anti-stress biomodulator that functions by affecting the brain.

Cephalopods have the most advanced nervous systems and intelligent behavior among all invertebrates. Their brains provide comparative insights for understanding the molecular and functional origins of the human brain. Although brain maps that contain information on the organization of each subregion are necessary for a study on the brain, no whole brain atlas for adult cephalopods has been constructed to date. Here, we obtained sagittal and coronal sections covering the entire brain of adult Octopus minor (Sasaki), which belongs to the genus with the most species in the class Cephalopoda and is commercially available in East Asia throughout the year. Sections were stained using Hematoxylin and Eosin (H&E) to visualize the cellular nuclei and subregions. H&E images of the serial sections were obtained at 30~70-µm intervals for the sagittal plain and at 40~80-µm intervals for the coronal plain. Setting the midline point of the posterior end as the fiducial point, we also established the distance coordinates of each image. We found that the brain had the typical brain structure of the Octopodiformes. A number of subregions were discriminated by a Hematoxylin-positive layer, the thickness and neuronal distribution pattern of which varied markedly depending upon the region. We identified more than 70 sub-regions based on delineations of representative H&E images. This is the first brain atlas, not only for an Octopodiformes species but also among adult cephalopods, and we anticipate that this atlas will provide a valuable resource for comparative neuroscience research.
Adult ; Arm* ; Brain* ; Cephalopoda ; Eosine Yellowish-(YS) ; Far East ; Hematoxylin ; Histology, Comparative ; Humans ; Invertebrates ; Nervous System ; Neurons ; Neurosciences ; Octopodiformes*