Bright and water-dispersible membrane probes enable visualization of cellular morphologies and dynamics in light-scattering tissues of living mice.

Fluorescent plasma membrane probes are indispensable tools for biological studies, enabling the visualization of the fine structure and dynamics of plasma membranes, and, by extension, the overall morphology of living cells. However, their use has been mostly limited to imaging cultured cells or fixed tissue slices. Indeed, few probes have been optimized for visualizing cellular morphologies in intact tissues or organs.

Experimental analysis of choice behavior in Japanese eel (Anguilla japonica).

The choice behavior of Japanese eels was analyzed using a generalized matching law. The eels were trained to select between two pipes in a water pool apparatus. Upon entering a pipe, the subjects received reinforcement in the form of a fixed stay duration, which varied from 10 to 2 min, resulting in different reinforcement magnitudes.

Correction: Synthesis and photophysical properties of a new push-pull pyrene dye with green-to-far-red emission and its application to human cellular and skin tissue imaging.

Correction for 'Synthesis and photophysical properties of a new push-pull pyrene dye with green-to-far-red emission and its application to human cellular and skin tissue imaging' by Kazuki Inoue , , 2022, , 1641-1649, https://doi.org/10.1039/D1TB02728J.

Do Cockatiels Choose Their Favourite Tunes? Use of Touchscreen for Animal Welfare Enhancement and Insights into Musical Preferences.

Music may be one of the oldest forms of art, and its appreciation is thought to be universal among humans. Music could also represent a useful tool to improve captive animals' welfare, especially if individuals can choose the music they prefer. The ability to discriminate between different kinds of music or composers has been demonstrated in numerous non-human species.

Synthesis of 1,3-Dibromopyrene as Precursor of 1-, 3-, 6-, and 8-Substituted Long-Axially Symmetric Pyrene Derivatives.

Pyrene derivatives bearing substituents at positions 1, 3, 6, and 8 find numerous applications, as exemplified by their use in lasers, sensors, and bioimaging probes. However, these derivatives typically have point-symmetric or short-axially symmetric structures, whereas long-axially symmetric derivatives remain underexplored because of the difficulty in obtaining their precursor, 1,3-dibromopyrene. To address this problem, we herein synthesized 1,3-dibromopyrene from 1-methoxypyrene in an overall yield (71 % over four steps) considerably exceeding those of existing methods.

Analysis of visual discrimination in Japanese eel (Anguilla japonica).

Japanese eels were trained to discriminate between a checkerboard panel and a plain gray panel in a circular pool with three pipes. One of the pipes was open, whereas the others were closed. The correct choice of discriminative stimulus was reinforced by entering the pipe.

Spontaneous tempo production in cockatiels (Nymphicus hollandicus) and jungle crows (Corvus macrorhynchos).

Musical and rhythmical abilities are poorly documented in non-human animals. Most of the existing studies focused on synchronisation performances to external rhythms. In humans, studies demonstrated that rhythmical processing (e.

A versatile and fast-sampling rate wearable analog data logger.

We propose a wearable, versatile, and open-source data logger that harvests the capacities of a low-cost microcontroller and enables fast-sampling recording of Analog signals into a microSD card. We describe here the circuit design and an exhaustive list of instructions to build a small, lightweight, and fast sampling rate data logger (up to 5 kHz for simultaneous recording of 3 channels and up to 40 kHz when using a single channel). We provide data analysis instructions, including publicly available scripts to facilitate its replication and customization.

Infrared thermography for non-invasive measurement of social inequality aversion in rodents and potential usefulness for future animal-friendly studies.

Infrared thermography is a method that detects thermal radiation energy and can measure the body surface temperature of animals from a distance. While rectal temperature has traditionally been used to measure animals' core temperature, thermal imaging can avoid the stress and potential rise of body temperature deriving from handling of the animals. Additionally, being non-invasive and contactless, thermal imaging allows free movement of the animals.

NIR-II-Excitable Dye-Loaded Nanoemulsions for Two-Photon Microscopy Imaging of Capillary Blood Vessels in the Entire Hippocampal CA1 Region of Living Mice.

For in vivo two-photon fluorescence microscopy (2PM) imaging, the development of techniques that can improve the observable depth and temporal resolution is an important challenge to address biological and biomedical concerns such as vascular dynamics in the deep brain (typically the hippocampal region) of living animals. Improvements have been achieved through two approaches: an optical approach using a highly tissue-penetrating excitation laser oscillating in the second near-infrared wavelength region (NIR-II, 1100-1350 nm) and a chemical approach employing fluorescent probes with high two-photon brightness (characterized by the product of the two-photon absorption cross section, σ, and the fluorescence quantum yield, Φ). To integrate these two approaches, we developed a fluorescent dye exhibiting a sufficiently high σΦ value of 68 Goeppert-Mayer units at 1100 nm.

Philadelphia Chromosome-positive Acute Lymphoblastic Leukemia Incidentally Detected by Fluorodeoxyglucose-positron Emission Tomography/Computed Tomography at a Health Checkup.

We herein report a case of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-ALL) that was incidentally detected by fluorodeoxyglucose-positron emission tomography (F-FDG PET)/computed tomography (CT) at a health checkup. At that time, the findings of a physical examination and blood tests were all normal, except for the diffuse bone marrow uptake (maximum standardized uptake value: 6.3).

Synthesis and photophysical properties of a new push-pull pyrene dye with green-to-far-red emission and its application to human cellular and skin tissue imaging.

Herein, we discuss a new pyrene-based push-pull dye (PC) and our investigation of its photophysical properties and applicability to biological studies. The newly synthesized dye exhibits highly polarity-sensitive fluorescence over a significantly wide range (, the green to far-red region), accompanied by high fluorescence quantum yields ( > 0.70 in most organic solvents) and superior photostability to that of the commonly used Nile Red (NR) dye, which also fluoresces in the green to red region.

Higher-Order Conditioning in the Spatial Domain.

Spatial learning and memory, the processes through which a wide range of living organisms encode, compute, and retrieve information from their environment to perform goal-directed navigation, has been systematically investigated since the early twentieth century to unravel behavioral and neural mechanisms of learning and memory. Early theories about learning to navigate space considered that animals learn through trial and error and develop responses to stimuli that guide them to a goal place. According to a trial-and error learning view, organisms can learn a sequence of motor actions that lead to a goal place, a strategy referred to as response learning, which contrasts with place learning where animals learn locations with respect to an allocentric framework.

Impairments in spatial learning by telencephalic lesions in Japanese eels (Anguilla japonica).

This study aimed to use Japanese eels (Anguilla japonica) as subjects to examine the effects of telencephalic lesions on spatial learning. Ten Japanese eels were trained on a Morris-type spatial learning task. Four pipes were placed in a pool; however, the eels could hide in only one of these pipes.

Preference and discrimination of facial expressions of humans, rats, and mice by C57 mice.

Social animals likely recognize emotional expressions in other animals. Recent studies suggest that mice can visually perceive emotional expressions of other mice. In the first experiment, we measured the preference of mice for two different facial expressions (a normal facial expression and an expression of negative emotion such as pain) of rats, mice, and humans.

Visual snake aversion in Octodon degus and C57BL/6 mice.

Phobia against spiders or snakes is common in humans, and similar phobia-like behaviors have been observed in non-human animals. Visual images of snakes elicit phobia in humans, but sensory modalities that cause snake aversion in non-human animals are not well examined. In this study, we examined visually induced snake aversion in two rodent species.

Spatial inference without a cognitive map: the role of higher-order path integration.

The cognitive map has been taken as the standard model for how agents infer the most efficient route to a goal location. Alternatively, path integration - maintaining a homing vector during navigation - constitutes a primitive and presumably less-flexible strategy than cognitive mapping because path integration relies primarily on vestibular stimuli and pace counting. The historical debate as to whether complex spatial navigation is ruled by associative learning or cognitive map mechanisms has been challenged by experimental difficulties in successfully neutralizing path integration.

Spatial Learning in Japanese Eels Using Extra- and Intra-Maze Cues.

Japanese eels () were trained on a spatial-learning paradigm in a pool placed in an experimental room where several extra-maze cues were present. Four tubes were placed in the pool, of which one was open and could be entered by the eels. The open tube was placed at a fixed position in the pool and contained a triangular block that served as an intra-maze cue.

Discrimination of artificial starry sky by pigeons.

Night migratory birds use the star compass for their navigation. Here, I examined discrimination of a starry sky by a nonmigratory bird, the pigeon. Four pigeons were trained in an operant chamber to discriminate between an artificial starry sky created using software (Stella Theater Pro) and a black sky without stars.

The whole is equal to the sum of its parts: Pigeons (Columba livia) and crows (Corvus macrorhynchos) do not perceive emergent configurations.

We previously demonstrated that chimpanzees, like humans, showed better accuracy and faster response time in discriminating visual patterns when the patterns were presented in redundant and uninformative contexts than when they were presented alone. In the present study, we examined the effect of redundant context on pattern discrimination in pigeons (Columba livia) and large-billed crows (Corvus macrorhynchos) using the same task and stimuli as those used in our previous study on chimpanzees. Birds were trained to search for an odd target among homogenous distractors.

Spatial learning in Japanese eels (Anguilla japonica).

Japanese eels (Anguilla japonica) were trained on a Morris-type spatial learning task. There were four tubes in a pool, but the eels could hide in only one of these. The eels learned the position of the open tube, and maintained their performance when the pool was rotated to remove possible intra-maze cues.

Dark-Field Microscopic Detection of Bacteria using Bacteriophage-Immobilized SiO@AuNP Core-Shell Nanoparticles.

To replace molecular biological and immunological methods, biosensors have recently been developed for the rapid and sensitive detection of bacteria. Among a wide variety of biological materials, bacteriophages have received increasing attention as promising alternatives to antibodies in biosensor applications. Thus, we herein present a rapid and highly selective detection method for pathogenic bacteria, which combines dark-field light scattering imaging with a plasmonic biosensor system.

Bright and two-photon active red fluorescent dyes that selectively move back and forth between the mitochondria and nucleus upon changing the mitochondrial membrane potential.

Since mitochondrial dysfunction was discovered to be the underlying cause of several severe diseases, fluorescent probes with excellent optical properties for visualising and monitoring the mitochondrial membrane potential (MMP) (a parameter of mitochondrial vitality) have been in high demand. Herein, we present novel pyrene-based dyes exhibiting remarkably large two-photon absorption around 900 nm and bright red emission around 620 nm (two-photon brightness (Φσ) = 425-525 GM), with selective localisation to the mitochondria or nucleus in response to changes in the MMP, providing several advantages over traditional MMP-monitoring probes such as Rhodamine 123 (Φσ = 64 GM). The intracellular behavior of the new dyes was investigated in detail.