scholarly journals Evolutionarily conserved anatomical and physiological properties of olfactory pathway till fourth order neurons in a species of grasshopper(Hieroglyphus banian)

2018 ◽  
Author(s):  
Shilpi Singh ◽  
Joby Joseph
Keyword(s):  
Fourth Order ◽  
Antennal Lobe ◽  
Olfactory Pathway ◽  
New Class ◽  
Physiological Properties ◽  
Evolutionarily Conserved ◽  
Olfactory Stimuli ◽  
Olfactory Systems ◽  
First Time

AbstractOlfactory systems of different species show variations in structure and physiology despite some conserved characteristics. We characterized the olfactory circuit of the grasshopperHieroglyphus banianof family Acrididae (subfamily: Hemiacridinae) and compared it to a well-studied species of locust,Schistocerca americana(subfamily: Cyrtacanthacridinae), also belonging to family Acrididae. We used in vivo electrophysiological, immunohistochemical and anatomical (bulk tract tracing) methods to elucidate the olfactory pathway from the second order neurons in antennal lobe to the fourth order neurons in β-lobe ofH. banian.We observe highly conserved anatomical and physiological characteristics till the fourth order neurons in the olfactory circuit ofH. banianandS. americana, though they are evolutionarily divergent (~57 million years ago). However, we found one major difference between the two species-there are four antennal lobe tracts inH. banianwhile only one is reported inS. americana. Besides, we are reporting for the first time, a new class of bilateral neurons which respond weakly to olfactory stimuli even though they innervate densely downstream of Kenyon cells.

scholarly journals The antimicrobial potential of cannabidiol

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Mark A. T. Blaskovich ◽  
Angela M. Kavanagh ◽  
Alysha G. Elliott ◽  
Bing Zhang ◽  
Soumya Ramu ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Modern Medicine ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
New Class ◽  
Clostridioides Difficile ◽  
Excellent Activity ◽  
Induce Resistance ◽  
First Time

AbstractAntimicrobial resistance threatens the viability of modern medicine, which is largely dependent on the successful prevention and treatment of bacterial infections. Unfortunately, there are few new therapeutics in the clinical pipeline, particularly for Gram-negative bacteria. We now present a detailed evaluation of the antimicrobial activity of cannabidiol, the main non-psychoactive component of cannabis. We confirm previous reports of Gram-positive activity and expand the breadth of pathogens tested, including highly resistant Staphylococcus aureus, Streptococcus pneumoniae, and Clostridioides difficile. Our results demonstrate that cannabidiol has excellent activity against biofilms, little propensity to induce resistance, and topical in vivo efficacy. Multiple mode-of-action studies point to membrane disruption as cannabidiol’s primary mechanism. More importantly, we now report for the first time that cannabidiol can selectively kill a subset of Gram-negative bacteria that includes the ‘urgent threat’ pathogen Neisseria gonorrhoeae. Structure-activity relationship studies demonstrate the potential to advance cannabidiol analogs as a much-needed new class of antibiotics.

Fabrication and Characterization of Biodegradable Metal Based Microelectrodes for In Vivo Neural Recording

MRS Advances ◽  
2019 ◽  
Vol 4 (46-47) ◽  
pp. 2471-2477
Author(s):  
Chaoxing Zhang ◽  
Teresa H. Wen ◽  
Khaleel A. Razak ◽  
Jiajia Lin ◽  
Edgar Villafana ◽  
...  
Keyword(s):  
Neural Recording ◽  
Neural Signals ◽  
Secondary Surgery ◽  
New Class ◽  
Fabrication And Characterization ◽  
Evoked Activity ◽  
First Time ◽  
The Brain

ABSTRACT:Neural electrodes have been widely used to monitor neural signals and/or deliver electrical stimulation in the brain. Currently, biodegradable and biocompatible materials have been actively investigated to create temporary electrodes that could degrade after serving their functions for neural recording and stimulation from days to months. The new class of biodegradable electrodes eliminate the necessity of secondary surgery for electrode removal. In this study, we created biodegradable, biocompatible, and implantable magnesium (Mg)-based microelectrodes for in vivo neural recording for the first time. Specifically, conductive poly-3,4-ethylenedioxythiophene (PEDOT) was first deposited onto Mg microwire substrates by electrochemical deposition, and a biodegradable insulating polymer was subsequently sprayed onto the surface of electrodes. The tip of electrodes was designed to be conductive for neural recording and stimulation, while the rest of electrodes was insulated with a polymer that is biocompatible with neural tissue. The impedance of Mg-based microelectrodes and their performance during neural recording in the auditory cortex of a mouse were studied. The results first demonstrated the capability of Mg-based microelectrodes for in vivo recording of multi-unit stimulus-evoked activity in the brain.

Direct and glia-mediated effects of GABA on development of central olfactory neurons

2011 ◽  
Vol 7 (2-4) ◽  
pp. 143-161
Author(s):  
Heather S. Mallory ◽  
Nicholas J. Gibson ◽  
Jon H. Hayashi ◽  
Alan J. Nighorn ◽  
Lynne A. Oland
Keyword(s):  
Glial Cells ◽  
Antennal Lobe ◽  
Neuronal Morphology ◽  
Projection Neurons ◽  
Olfactory Pathway ◽  
Mediated Effects ◽  
Local Interneurons ◽  
Outward Currents ◽  
Olfactory Glomeruli

Previously studied for its role in processing olfactory information in the antennal lobe, GABA also may shape development of the olfactory pathway, acting either through or on glial cells. Early in development, the dendrites of GABAergic neurons extend to the glial border that surrounds the nascent olfactory lobe neuropil. These neuropil glia express both GABAA and GABAB receptors, about half of the glia in acute cultures responded to GABA with small outward currents, and about a third responded with small transient increases in intracellular calcium. The neuronal classes that express GABA in vivo, the local interneurons and a subset of projection neurons, also do so in culture. Exposure to GABA in culture increased the size and complexity of local interneurons, but had no effect on glial morphology. The presence of glia alone did not affect neuronal morphology, but in the presence of both glia and GABA, the growth-enhancing effects of GABA on cultured antennal lobe neurons were eliminated. Contact between the glial cells and the neurons was not necessary. Operating in vivo, these antagonistic effects, one direct and one glia mediated, could help to sculpt the densely branched, tufted arbors that are characteristic of neurons innervating olfactory glomeruli.

scholarly journals Classification of odorants across layers in locust olfactory pathway

2016 ◽  
Vol 115 (5) ◽  
pp. 2303-2316 ◽  
Author(s):  
Pavel Sanda ◽  
Tiffany Kee ◽  
Nitin Gupta ◽  
Mark Stopfer ◽  
Maxim Bazhenov
Keyword(s):  
Antennal Lobe ◽  
Error Rates ◽  
Classification Error ◽  
Mushroom Bodies ◽  
Insect Brain ◽  
Projection Neurons ◽  
Olfactory Pathway ◽  
Lateral Horn ◽  
Odor Classification

Olfactory processing takes place across multiple layers of neurons from the transduction of odorants in the periphery, to odor quality processing, learning, and decision making in higher olfactory structures. In insects, projection neurons (PNs) in the antennal lobe send odor information to the Kenyon cells (KCs) of the mushroom bodies and lateral horn neurons (LHNs). To examine the odor information content in different structures of the insect brain, antennal lobe, mushroom bodies and lateral horn, we designed a model of the olfactory network based on electrophysiological recordings made in vivo in the locust. We found that populations of all types (PNs, LHNs, and KCs) had lower odor classification error rates than individual cells of any given type. This improvement was quantitatively different from that observed using uniform populations of identical neurons compared with spatially structured population of neurons tuned to different odor features. This result, therefore, reflects an emergent network property. Odor classification improved with increasing stimulus duration: for similar odorants, KC and LHN ensembles reached optimal discrimination within the first 300–500 ms of the odor response. Performance improvement with time was much greater for a population of cells than for individual neurons. We conclude that, for PNs, LHNs, and KCs, ensemble responses are always much more informative than single-cell responses, despite the accumulation of noise along with odor information.

scholarly journals Direct visualization of a native Wnt in vivo reveals that a long-range Wnt gradient forms by extracellular dispersal

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Ariel M Pani ◽  
Bob Goldstein
Keyword(s):  
Long Range ◽  
Direct Evidence ◽  
Signaling Proteins ◽  
Long Distance ◽  
Biologically Relevant ◽  
C Elegans ◽  
Neuroblast Migration ◽  
Evolutionarily Conserved ◽  
First Time

Wnts are evolutionarily conserved signaling proteins with essential roles in development and disease that have often been thought to spread between cells and signal at a distance. However, recent studies have challenged this model, and whether long-distance extracellular Wnt dispersal occurs and is biologically relevant is debated. Understanding fundamental aspects of Wnt dispersal has been limited by challenges with observing endogenous ligands in vivo, which has prevented directly testing hypotheses. Here, we have generated functional, fluorescently tagged alleles for a C. elegans Wnt homolog and for the first time visualized a native, long-range Wnt gradient in a living animal. Live imaging of Wnt along with source and responding cell membranes provided support for free, extracellular dispersal. By limiting Wnt transfer between cells, we confirmed that extracellular spreading shapes a long-range gradient and is critical for neuroblast migration. These results provide direct evidence that Wnts spread extracellularly to regulate aspects of long-range signaling.

Conjugates of Classical DNA/RNA Binder with Nucleobase: Chemical, Biochemical and Biomedical Applications

2019 ◽  
Vol 26 (30) ◽  
pp. 5609-5624
Author(s):  
Dijana Saftić ◽  
Željka Ban ◽  
Josipa Matić ◽  
Lidija-Marija Tumirv ◽  
Ivo Piantanida
Keyword(s):  
Molecular Weight ◽  
Small Molecules ◽  
Biomedical Applications ◽  
Protein Targets ◽  
New Class ◽  
Rna Targets ◽  
Covalently Linked ◽  
Structural Aspects

: Among the most intensively studied classes of small molecules (molecular weight < 650) in biomedical research are small molecules that non-covalently bind to DNA/RNA, and another intensively studied class is nucleobase derivatives. Both classes have been intensively elaborated in many books and reviews. However, conjugates consisting of DNA/RNA binder covalently linked to nucleobase are much less studied and have not been reviewed in the last two decades. Therefore, this review summarized reports on the design of classical DNA/RNA binder – nucleobase conjugates, as well as data about their interactions with various DNA or RNA targets, and even in some cases protein targets are involved. According to these data, the most important structural aspects of selective or even specific recognition between small molecule and target are proposed, and where possible related biochemical and biomedical aspects were discussed. The general conclusion is that this, rather new class of molecules showed an amazing set of recognition tools for numerous DNA or RNA targets in the last two decades, as well as few intriguing in vitro and in vivo selectivities. Several lead research lines show promising advancements toward either novel, highly selective markers or bioactive, potentially druggable molecules.

scholarly journals Hexapod Assassins’ Potion: Venom Composition and Bioactivity from the Eurasian Assassin Bug Rhynocoris iracundus

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 819
Author(s):  
Nicolai Rügen ◽  
Timothy P. Jenkins ◽  
Natalie Wielsch ◽  
Heiko Vogel ◽  
Benjamin-Florian Hempel ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Galleria Mellonella ◽  
Systemic Reactions ◽  
Venom Composition ◽  
Assassin Bug ◽  
Molecular Components ◽  
First Time ◽  
Tissue Digestion

Assassin bug venoms are potent and exert diverse biological functions, making them potential biomedical goldmines. Besides feeding functions on arthropods, assassin bugs also use their venom for defense purposes causing localized and systemic reactions in vertebrates. However, assassin bug venoms remain poorly characterized. We collected the venom from the assassin bug Rhynocoris iracundus and investigated its composition and bioactivity in vitro and in vivo. It caused lysis of murine neuroblastoma, hepatoma cells, and healthy murine myoblasts. We demonstrated, for the first time, that assassin bug venom induces neurolysis and suggest that it counteracts paralysis locally via the destruction of neural networks, contributing to tissue digestion. Furthermore, the venom caused paralysis and melanization of Galleria mellonella larvae and pupae, whilst also possessing specific antibacterial activity against Escherichia coli, but not Listeria grayi and Pseudomonas aeruginosa. A combinatorial proteo-transcriptomic approach was performed to identify potential toxins responsible for the observed effects. We identified neurotoxic Ptu1, an inhibitory cystin knot (ICK) toxin homologous to ω-conotoxins from cone snails, cytolytic redulysins homologous to trialysins from hematophagous kissing bugs, and pore-forming hemolysins. Additionally, chitinases and kininogens were found and may be responsible for insecticidal and cytolytic activities. We demonstrate the multifunctionality and complexity of assassin bug venom, which renders its molecular components interesting for potential biomedical applications.

Carbon dots derived from Fusobacterium nucleatum for intracellular determination of Fe3+ and bioimaging both in vitro and in vivo

2021 ◽  
Author(s):  
Lijuan Liu ◽  
Shengting Zhang ◽  
Xiaodan Zheng ◽  
Hongmei Li ◽  
Qi Chen ◽  
...  
Keyword(s):  
Carbon Dots ◽  
Fusobacterium Nucleatum ◽  
Living Cells ◽  
First Time ◽  
Fluorescent Carbon Dots ◽  
Fluorescent Carbon

Fusobacterium nucleatum has been employed for the first time to synthesize fluorescent carbon dots which could be applied for the determination of Fe3+ ions in living cells and bioimaging in vitro and in vivo with excellent biocompatibility.

scholarly journals Anti-Tumor and Anti-Inflammatory Activity In Vivo of Apodanthera congestiflora Cogn. (Cucurbitaceae)

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 743
Author(s):  
Geovana F. G. Silvestre ◽  
Renally P. Lucena ◽  
Genil D. Oliveira ◽  
Helimarcos N. Pereira ◽  
Jhonatta A. B. Dias ◽  
...  
Keyword(s):  
Inflammatory Activity ◽  
Phytochemical Investigation ◽  
Significant Toxicity ◽  
Biological Tests ◽  
Ehrlich's Carcinoma ◽  
Anti Inflammatory ◽  
Pharmacological Potential ◽  
First Time ◽  
Anti Tumor Activity

This work aimed to carry out a study of Apodanthera congestiflora by investigating its chemical composition and pharmacological potential. From the dichloromethane phase (Dic-Ac) of the A. congestiflora stems, three compounds were identified: cayaponoside C5b (Ac-1), cabenoside C (Ac-2) and fevicordin C2 glucoside (Ac-3), being last identified for the first time as a natural product. These compounds were obtained by chromatographic methods and their structures were elucidated by means of spectroscopic analysis of IR, MS and NMR. In the quantification of Dic-Ac, it was possible to observe the presence of 7% of cayaponoside C5b. Dic-Ac showed significant toxicity for in vivo tests, with macroscopic and biochemical changes. The anti-inflammatory activity of Dic-Ac was investigated using the paw edema model. A decrease in inflammatory signs was observed in the first 5 h and the most effective dose in reducing edema with was 7.5 mg kg−1 (66.6%). Anti-tumor activity of Dic-Ac was evaluated by Ehrlich’s carcinoma model, which showed inhibition rate of 78.46% at 15 mg kg−1 dosage. The phytochemical investigation, together with the biological tests carried out in this study, demonstrated that A. congestiflora is a promising species in the search for therapeutics, since it contains substances with high pharmacological potential in its composition.

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