Sound generation in zebrafish with Bio-Opto-Acoustics

AbstractHearing is a crucial sense in underwater environments for communication, hunting, attracting mates, and detecting predators. However, the tools currently used to study hearing are limited, as they cannot controllably stimulate specific parts of the auditory system. To date, the contributions of hearing organs have been identified through lesion experiments that inactivate an organ, making it difficult to gauge the specific stimuli to which each organ is sensitive, or the ways in which inputs from multiple organs are combined during perception. Here, we introduce Bio-Opto-Acoustic (BOA) stimulation, using optical forces to generate localized vibrations in vivo, and demonstrate stimulation of the auditory system of zebrafish larvae with precise control. We use a rapidly oscillated optical trap to generate vibrations in individual otolith organs that are perceived as sound, while adjacent otoliths are either left unstimulated or similarly stimulated with a second optical laser trap. The resulting brain-wide neural activity is characterized using fluorescent calcium indicators, thus linking each otolith organ to its individual neuronal network in a way that would be impossible using traditional sound delivery methods. The results reveal integration and cooperation of the utricular and saccular otoliths, which were previously described as having separate biological functions, during hearing.

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Sound generation in zebrafish with Bio-Opto-Acoustics (BOA)

10.1101/2020.06.09.143362 ◽

2020 ◽

Cited By ~ 1

Author(s):

Itia A. Favre-Bulle ◽

Michael A. Taylor ◽

Emmanuel Marquez-Legorreta ◽

Gilles Vanwalleghem ◽

Rebecca E. Poulsen ◽

...

Keyword(s):

Auditory System ◽

Optical Trap ◽

Otolith Organs ◽

Otolith Organ ◽

Delivery Methods ◽

Multiple Organs ◽

Laser Trap ◽

Calcium Indicators ◽

Optical Laser

Hearing is a crucial sense in underwater environments for communication, hunting, attracting mates, and detecting predators. However, the tools currently used to study hearing are limited, as they cannot controllably stimulate specific parts of the auditory system. To date, the contributions of hearing organs have been identified through lesion experiments that inactivate an organ, but this makes it difficult to gauge the specific stimuli to which each organ is sensitive, or the ways in which inputs from multiple organs are combined during perception. Here, we introduce Bio-Opto-Acoustic (BOA) stimulation, using optical forces to generate localized sound in vivo, and demonstrate stimulation of the auditory system of zebrafish larvae with unprecedented control. We use a rapidly oscillated optical trap to generate vibrations in individual otolith organs that are perceived as sound, while adjacent otoliths are either left unstimulated or similarly stimulated with a second optical laser trap. The resulting brain-wide neural activity is characterized using fluorescent calcium indicators, thus linking each otolith organ to its individual neuronal network in a way that would be impossible using traditional sound delivery methods. The results reveal integration and cooperation of the utricular and saccular otoliths, which were previously described as having separate biological functions, during hearing.

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COVID-19: Opinion in Prevention and dietary based management hypothesis

Coronaviruses ◽

10.2174/2666796701999200623172916 ◽

2020 ◽

Vol 01 ◽

Author(s):

Ashraf Talaat Youssef

Keyword(s):

Fatty Acids ◽

Saturated Fatty Acids ◽

Lung Damage ◽

Gastric Aspirate ◽

Enveloped Viruses ◽

Multiple Organs ◽

Fold Reduction ◽

Antiviral Activities

The pandemic of COVID-19 had started in Wuhan city china in late 2019 with a subsequent worldwide spread. The viral infection can seriousely affect multiple organs mainly lungs, kidneys, heart, liver and brain and may lead to respiratory, renal, cardiac or hepatic failure.Vascular thrombosis of unexplained mechanism that may lead to widespread blood clots in multiple organs and cytokine storms that result of overstimulation of the immune system subsequent of lung damage may lead to sudden decompensation due to hypotension and more damage to liver, kidney, brain or lungs.Until now no drug had proved efficient in getting rid of the problem and controlling the pandemic mainly depends on preventive measures.Many preventive measures can be considered to prevent the worldwide spread of viral transmission. Polyunsaturated long chain fatty acids (PUFAs) and the medium chain saturated fatty acids (MCSFAs) and their corresponding monoglycerides had high antiviral activities against the enveloped viruses which reach to more than 10,000 -fold reduction in the viral titres in vitro and in vivo after testing of its gastric aspirate, and can contribute to the systemic immunity against the enveloped viruses.

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Biomechanics of Neutrophil Tethers

Life ◽

10.3390/life11060515 ◽

2021 ◽

Vol 11 (6) ◽

pp. 515

Author(s):

Andrea Cugno ◽

Alex Marki ◽

Klaus Ley

Keyword(s):

Cell Activation ◽

Optical Trap ◽

Biomechanical Properties ◽

Force Microscopy ◽

Advantages And Disadvantages ◽

Atomic Force ◽

Microfluidic Flow ◽

Biomembrane Force Probe ◽

Membrane Reservoir

Leukocytes, including neutrophils, which are propelled by blood flow, can roll on inflamed endothelium using transient bonds between selectins and their ligands, and integrins and their ligands. When such receptor–ligand bonds last long enough, the leukocyte microvilli become extended and eventually form thin, 20 m long tethers. Tether formation can be observed in blood vessels in vivo and in microfluidic flow chambers. Tethers can also be extracted using micropipette aspiration, biomembrane force probe, optical trap, or atomic force microscopy approaches. Here, we review the biomechanical properties of leukocyte tethers as gleaned from such measurements and discuss the advantages and disadvantages of each approach. We also review and discuss viscoelastic models that describe the dependence of tether formation on time, force, rate of loading, and cell activation. We close by emphasizing the need to combine experimental observations with quantitative models and computer simulations to understand how tether formation is affected by membrane tension, membrane reservoir, and interactions of the membrane with the cytoskeleton.

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Calcium functional imaging with high-resolution CT in the inner ear

Scientific Reports ◽

10.1038/s41598-021-94857-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hisaya Tanioka ◽

Sayaka Tanioka

Keyword(s):

Internal State ◽

Texture Synthesis ◽

Biological Information ◽

Endolymphatic Sac ◽

Otolith Organs ◽

Synthesis Algorithm ◽

Utricular Macula ◽

Positional Vertigo ◽

Paroxysmal Positional Vertigo

AbstractAlthough the otolith and otolith organs correlate with vertigo and instability, there is no method to investigate them without harmful procedures. We will create the technique for 3D microanatomical images of them, and investigate the in vivo internal state and metabolisms. The otolith and otolith organs images were reconstructed from a texture synthesis algorithm under the skull volume rendering algorithm using a cutting-plane method. The utricular macula was elongated pea-shaped. The saccular macula was almost bud-shaped. The changes in the amount of CaCO3 in the maculae and the endolymphatic sac showed various morphologies, reflecting the balance status of each subject. Both shapes and volumes were not always constant depending on time. In Meniere’s disease (MD), the saccular macula was larger and the utricular macula was smaller. In benign paroxysmal positional vertigo (BPPV), the otolith increased in the utricular macula but did not change much in the saccular macula. The saccule, utricle, and endolymphatic sac were not constantly shaped according to their conditions. These created 3D microanatomical images can allow detailed observations of changes in physiological and biological information. This imaging technique will contribute to our understanding of pathology and calcium metabolism in the in vivo vestibulum.

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Abrogation of Neuraminidase Reduces Biofilm Formation, Capsule Biosynthesis, and Virulence of Porphyromonas gingivalis

Infection and Immunity ◽

10.1128/iai.05773-11 ◽

2011 ◽

Vol 80 (1) ◽

pp. 3-13 ◽

Cited By ~ 27

Author(s):

Chen Li ◽

Kurniyati ◽

Bo Hu ◽

Jiang Bian ◽

Jianlan Sun ◽

...

Keyword(s):

Porphyromonas Gingivalis ◽

Biofilm Formation ◽

Adult Population ◽

Transcriptional Analysis ◽

Wild Type ◽

Content Type ◽

Multiple Organs ◽

Biochemical Analyses

ABSTRACTThe oral bacteriumPorphyromonas gingivalisis a key etiological agent of human periodontitis, a prevalent chronic disease that affects up to 80% of the adult population worldwide.P. gingivalisexhibits neuraminidase activity. However, the enzyme responsible for this activity, its biochemical features, and its role in the physiology and virulence ofP. gingivalisremain elusive. In this report, we found thatP. gingivalisencodes a neuraminidase, PG0352 (SiaPg). Transcriptional analysis showed thatPG0352is monocistronic and is regulated by a sigma70-like promoter. Biochemical analyses demonstrated that SiaPgis an exo-α-neuraminidase that cleaves glycosidic-linked sialic acids. Cryoelectron microscopy and tomography analyses revealed that thePG0352deletion mutant (ΔPG352) failed to produce an intact capsule layer. Compared to the wild type,in vitrostudies showed that ΔPG352 formed less biofilm and was less resistant to killing by the host complement.In vivostudies showed that while the wild type caused a spreading type of infection that affected multiple organs and all infected mice were killed, ΔPG352 only caused localized infection and all animals survived. Taken together, these results demonstrate that SiaPgis an important virulence factor that contributes to the biofilm formation, capsule biosynthesis, and pathogenicity ofP. gingivalis, and it can potentially serve as a new target for developing therapeutic agents againstP. gingivalisinfection.

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THE ADJUSTABLE SYSTEMIC-PULMONARY ARTERY SHUNT OFFERS PRECISE CONTROL OF FLOW IN VIVO

ASAIO Journal ◽

10.1097/00002480-200603000-00101 ◽

2006 ◽

Vol 52 (2) ◽

pp. 21A

Author(s):

William I Douglas ◽

Karabeth B Moore ◽

Phillip R Resig ◽

Charles F Knapp ◽

Jamey D Jacob

Keyword(s):

Pulmonary Artery ◽

Precise Control ◽

Control Of Flow

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Stanniocalcin-1, an inhibitor of macrophage chemotaxis and chemokinesis

AJP Renal Physiology ◽

10.1152/ajprenal.00138.2003 ◽

2004 ◽

Vol 286 (2) ◽

pp. F356-F362 ◽

Cited By ~ 46

Author(s):

John Kanellis ◽

Roger Bick ◽

Gabriela Garcia ◽

Luan Truong ◽

Chun Chui Tsao ◽

...

Keyword(s):

Inflammatory Response ◽

Intracellular Calcium ◽

In Vivo Studies ◽

Cellular Processes ◽

Multiple Organs ◽

Chemotactic Protein ◽

Stromal Cell Derived Factor ◽

Mammalian Counterpart

In macrophages, changes in intracellular calcium have been associated with activation of cellular processes that regulate cell adhesion and motility and are important for the response of macrophages to antigenic stimuli. The mammalian counterpart of the fish calcium-regulating hormone stanniocalcin-1 (STC1) is expressed in multiple organs including the thymus and spleen, and hence, we hypothesized that it may have a role in modulating the immune/inflammatory response. Using murine macrophage-like (RAW264.7) and human monoblast-like (U937) cells to study chemotaxis in vitro, we found that STC1 attenuated chemokinesis and diminished the chemotactic response to monocyte chemotactic protein-1 (MCP-1) and stromal cell-derived factor-1α. Consistent with these findings, STC1 blunted the rise in intracellular calcium following MCP-1 stimulation in RAW264.7 cells. In vivo studies suggested differential expression of STC1 in obstructed kidney and localization to macrophages. MCP-1 and STC1 transcripts were both upregulated following ureteric obstruction, suggesting a functional association between the two genes. Our data suggest a role for mammalian STC1 in modulating the immune/inflammatory response.

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Modified Nanodiamonds as a Means of Polymer Surface Functionalization. From Fouling Suppression to Biosensor Design

Nanomaterials ◽

10.3390/nano11112980 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2980

Author(s):

Pavel V. Melnikov ◽

Anastasia Yu. Alexandrovskaya ◽

Alina O. Naumova ◽

Nadezhda M. Popova ◽

Boris V. Spitsyn ◽

...

Keyword(s):

Optical Sensors ◽

Polymer Surface ◽

Mixed Composition ◽

Precise Control ◽

Polar Groups ◽

Bactericidal Properties ◽

Wall Interaction ◽

Biosensor Response

The development of different methods for tuning surface properties is currently of great interest. The presented work is devoted to the use of modified nanodiamonds to control the wetting and biological fouling of polymers using optical sensors as an example. We have shown that, depending on the type of modification and the amount of nanodiamonds, the surface of the same fluorinated polymer can have both bactericidal properties and, on the contrary, good adhesion to the biomaterial. The precise control of wetting and biofouling properties of the surface was achieved by the optimization of the modified nanodiamonds thermal anchoring conditions. In vitro and in vivo tests have shown that the fixation of amine functional groups leads to inhibition of biological activity, while the presence of a large number of polar groups of mixed composition (amide and acid chloride) promotes adhesion of the biomaterial and allows one to create a biosensor on-site. A comprehensive study made it possible to establish that in the first 5 days the observed biosensor response is provided by cells adhered to the surface due to the cell wall interaction. On the 7th day, the cells are fixed by means of the polysaccharide matrix, which provides much better retention on the surface and a noticeably greater response to substrate injections. Nevertheless, it is important to note that even 1.5 h of incubation is sufficient for the formation of the reliable bioreceptor on the surface with the modified nanodiamonds. The approach demonstrated in this work makes it possible to easily and quickly isolate the microbiome on the surface of the sensor and perform the necessary studies of its substrate specificity or resistance to toxic effects.

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Extracellular SPARC cooperates with TGF-β signalling to induce pro-fibrotic activation of systemic sclerosis patient dermal fibroblasts

Rheumatology ◽

10.1093/rheumatology/kez583 ◽

2019 ◽

Vol 59 (9) ◽

pp. 2258-2263 ◽

Cited By ~ 3

Author(s):

Tiago Carvalheiro ◽

Beatriz Malvar Fernández ◽

Andrea Ottria ◽

Barbara Giovannone ◽

Wioleta Marut ◽

...

Keyword(s):

Protein Expression ◽

Therapeutic Target ◽

Dermal Fibroblasts ◽

Dependent Manner ◽

Healthy Controls ◽

Multiple Organs ◽

Extracellular Matrix Components ◽

Mrna And Protein Expression

Abstract Objectives SSc is an autoimmune disease characterized by inflammation, vascular injury and excessive fibrosis in multiple organs. Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein that regulates processes involved in SSc pathology, such as inflammation and fibrosis. In vivo and in vitro studies have implicated SPARC in SSc, but it is unclear if the pro-fibrotic effects of SPARC on fibroblasts are a result of intracellular signalling or fibroblast interactions with extracellular SPARC hampering further development of SPARC as a potential therapeutic target. This study aimed to analyse the potential role of exogenous SPARC as a regulator of fibrosis in SSc. Methods Dermal fibroblasts from both healthy controls and SSc patients were stimulated with SPARC alone or in combination with TGF-β1, in the absence or presence of a TGF receptor 1 inhibitor. mRNA and protein expression of extracellular matrix components and other fibrosis-related mediators were measured by quantitative PCR and western blot. Results Exogenous SPARC induced mRNA and protein expression of collagen I, collagen IV, fibronectin 1, TGF-β and SPARC by dermal fibroblasts from SSc patients, but not from healthy controls. Importantly, exogenous SPARC induced the activation of the tyrosine kinase SMAD2 and pro-fibrotic gene expression induced by SPARC in SSc fibroblasts was abrogated by inhibition of TGF-β signalling. Conclusion These results indicate that exogenous SPARC is an important pro-fibrotic mediator contributing to the pathology driving SSc but in a TGF-β dependent manner. Therefore, SPARC could be a promising therapeutic target for reducing fibrosis in SSc patients, even in late states of the disease.

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The aging skin microenvironment dictates stem cell behavior

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1901720117 ◽

2020 ◽

Vol 117 (10) ◽

pp. 5339-5350 ◽

Cited By ~ 12

Author(s):

Yejing Ge ◽

Yuxuan Miao ◽

Shiri Gur-Cohen ◽

Nicholas Gomez ◽

Hanseul Yang ◽

...

Keyword(s):

Dominant Role ◽

Functional Decline ◽

Cell Types ◽

Multiple Organs ◽

Age Related ◽

Hair Follicle Stem Cells ◽

Aged Skin ◽

Transcriptional Changes ◽

Follicle Stem Cells

Aging manifests with architectural alteration and functional decline of multiple organs throughout an organism. In mammals, aged skin is accompanied by a marked reduction in hair cycling and appearance of bald patches, leading researchers to propose that hair follicle stem cells (HFSCs) are either lost, differentiate, or change to an epidermal fate during aging. Here, we employed single-cell RNA-sequencing to interrogate aging-related changes in the HFSCs. Surprisingly, although numbers declined, aging HFSCs were present, maintained their identity, and showed no overt signs of shifting to an epidermal fate. However, they did exhibit prevalent transcriptional changes particularly in extracellular matrix genes, and this was accompanied by profound structural perturbations in the aging SC niche. Moreover, marked age-related changes occurred in many nonepithelial cell types, including resident immune cells, sensory neurons, and arrector pili muscles. Each of these SC niche components has been shown to influence HF regeneration. When we performed skin injuries that are known to mobilize young HFSCs to exit their niche and regenerate HFs, we discovered that aged skin is defective at doing so. Interestingly, however, in transplantation assays in vivo, aged HFSCs regenerated HFs when supported with young dermis, while young HFSCs failed to regenerate HFs when combined with aged dermis. Together, our findings highlight the importance of SC:niche interactions and favor a model where youthfulness of the niche microenvironment plays a dominant role in dictating the properties of its SCs and tissue health and fitness.

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