scholarly journals Characterization of proprioceptive system dynamics in behaving Drosophila larvae using high-speed volumetric microscopy

2018 ◽  
Author(s):  
Rebecca Vaadia ◽  
Wenze Li ◽  
Venkatakaushik Voleti ◽  
Aditi Singhania ◽  
Elizabeth M.C. Hillman ◽  
...  
Keyword(s):  
High Speed ◽  
Body Position ◽  
Activity Patterns ◽  
The Body ◽  
Larval Body ◽  
Activity Measurements ◽  
Natural Movement ◽  
Rigid Joints

SummaryProprioceptors provide feedback about body position that is essential for coordinated movement. Proprioceptive sensing of the position of rigid joints has been described in detail in several systems, however it is not known how animals with an elastic skeleton encode their body positions. Understanding how diverse larval body positions are dynamically encoded requires knowledge of proprioceptor activity patterns in vivo during natural movement. Here we applied high-speed volumetric SCAPE microscopy to simultaneously track the position, physical deformation, and temporal patterns of intracellular calcium activity of multidendritic proprioceptors in crawling Drosophila larvae. During the periodic segment contraction and relaxation that occurs during crawling, proprioceptors with diverse morphologies showed sequential onset of activity throughout each periodic episode. A majority of these proprioceptors showed activity during segment contraction with one neuron type activated by segment extension. Different timing of activity of contraction-sensing proprioceptors was related to distinct dendrite terminal targeting, providing a continuum of position encoding during all phases of crawling. These dynamics could endow different proprioceptors with specific roles in monitoring the progression of contraction waves, as well as body shape during other behaviors. We provide activity measurements during exploration as one example. Our results provide powerful new insights into the body-wide neuronal dynamics of the proprioceptive system in crawling Drosophila, and demonstrate the utility of our approach for characterization of neural encoding throughout the nervous system of a freely behaving animal.

In-vivo evaluation of cisplatin nanoparticles encompass natural polymer

2020 ◽  
Vol 6 (1) ◽  
pp. 1-7
Author(s):  
Bhavani J ◽  
Sunil Kumar Prajapati ◽  
Ravichandran S
Keyword(s):  
Tumor Volume ◽  
Nitrogen Mustard ◽  
Common Type ◽  
The Body ◽  
Nano Particles ◽  
Natural Polymer ◽  
Drinking Alcohol ◽  
In Vivo Evaluation

Cancer is assemblage diseases involving abnormal cell growth amid the potential of spread to other parts of the body due to tobacco use are the cause of about of cancer deaths. Another 10% is due to obesity, poor diet & drinking alcohol. In 2012 about 14.1 million new cases of cancer occurred globally. In females, the most common type is breast cancer. Cisplatin also known as cytophosphane is a nitrogen mustard alkylating agent from the oxazophosphinans groups were used to treat cancers & autoimmune disorders. Based on the above reasons I will fix the aim Preparation characterization of Cisplatin- nano particles  &  its anticancer activity. Solid tumor volume examination report showed that the assessment of different day indication 15,20,25 & 30th variations of different groups of tumor volumes were decreased CPG Nanoparticles (100 mg/kg)+ DAL(15th day 4.97±0.24↓), (20th day 0.6±0.13↓), (25th day 1.35±0.30↓) & (30th day 1.89±0.13↓).

scholarly journals A faster escape does not enhance survival in zebrafish larvae

2017 ◽  
Vol 284 (1852) ◽  
pp. 20170359 ◽  
Author(s):  
Arjun Nair ◽  
Christy Nguyen ◽  
Matthew J. McHenry
Keyword(s):  
High Speed ◽  
Larval Fish ◽  
Body Position ◽  
Three Dimensional ◽  
Limited Range ◽  
The Body ◽  
Model Parameters ◽  
Fish Prey ◽  
Zebrafish Larvae ◽  
Fish Predators

An escape response is a rapid manoeuvre used by prey to evade predators. Performing this manoeuvre at greater speed, in a favourable direction, or from a longer distance have been hypothesized to enhance the survival of prey, but these ideas are difficult to test experimentally. We examined how prey survival depends on escape kinematics through a novel combination of experimentation and mathematical modelling. This approach focused on zebrafish ( Danio rerio ) larvae under predation by adults and juveniles of the same species. High-speed three-dimensional kinematics were used to track the body position of prey and predator and to determine the probability of behavioural actions by both fish. These measurements provided the basis for an agent-based probabilistic model that simulated the trajectories of the animals. Predictions of survivorship by this model were found by Monte Carlo simulations to agree with our observations and we examined how these predictions varied by changing individual model parameters. Contrary to expectation, we found that survival may not be improved by increasing the speed or altering the direction of the escape. Rather, zebrafish larvae operate with sufficiently high locomotor performance due to the relatively slow approach and limited range of suction feeding by fish predators. We did find that survival was enhanced when prey responded from a greater distance. This is an ability that depends on the capacity of the visual and lateral line systems to detect a looming threat. Therefore, performance in sensing, and not locomotion, is decisive for improving the survival of larval fish prey. These results offer a framework for understanding the evolution of predator–prey strategy that may inform prey survival in a broad diversity of animals.

The C-start escape response ofPolypterus senegalus: bilateral muscle activity and variation during stage 1 and 2

2002 ◽  
Vol 205 (17) ◽  
pp. 2591-2603 ◽  
Author(s):  
Eric D. Tytell ◽  
George V. Lauder
Keyword(s):  
Muscle Activity ◽  
Escape Response ◽  
High Speed ◽  
Wave Speed ◽  
Activity Patterns ◽  
Motor Pattern ◽  
The Body ◽  
Wide Range ◽  
Fast Start ◽  
Stage 1

SUMMARYThe fast-start escape response is the primary reflexive escape mechanism in a wide phylogenetic range of fishes. To add detail to previously reported novel muscle activity patterns during the escape response of the bichir, Polypterus, we analyzed escape kinematics and muscle activity patterns in Polypterus senegalus using high-speed video and electromyography (EMG). Five fish were filmed at 250 Hz while synchronously recording white muscle activity at five sites on both sides of the body simultaneously (10 sites in total). Body wave speed and center of mass velocity, acceleration and curvature were calculated from digitized outlines. Six EMG variables per channel were also measured to characterize the motor pattern. P. senegalus shows a wide range of activity patterns, from very strong responses, in which the head often touched the tail, to very weak responses. This variation in strength is significantly correlated with the stimulus and is mechanically driven by changes in stage 1 muscle activity duration. Besides these changes in duration, the stage 1 muscle activity is unusual because it has strong bilateral activity, although the observed contralateral activity is significantly weaker and shorter in duration than ipsilateral activity. Bilateral activity may stiffen the body, but it does so by a constant amount over the variation we observed; therefore, P. senegalus does not modulate fast-start wave speed by changing body stiffness. Escape responses almost always have stage 2 contralateral muscle activity, often only in the anterior third of the body. The magnitude of the stage 2 activity is the primary predictor of final escape velocity.

Myotomal slow muscle function of rainbow trout Oncorhynchus mykiss during steady swimming.

1998 ◽  
Vol 201 (10) ◽  
pp. 1659-1671 ◽  
Author(s):  
L Hammond ◽  
J D Altringham ◽  
C S Wardle
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Body Length ◽  
Muscle Activation ◽  
Activity Patterns ◽  
The Body ◽  
Entire Body ◽  
Negative Power ◽  
Rainbow Trout Oncorhynchus Mykiss

Strain and activity patterns were determined during slow steady swimming (tailbeat frequency 1.5-2.5 Hz) at three locations on the body in the slow myotomal muscle of rainbow trout Oncorhynchus mykiss using sonomicrometry and electromyography. Strain was independent of tailbeat frequency over the range studied and increased significantly from +/-3.3 % l0 at 0.35BL to +/-6 % at 0.65BL, where l0 is muscle resting length and BL is total body length. Muscle activation occurred significantly later in the strain cycle at 0.35BL (phase shift 59 degrees) than at 0.65BL (30 degrees), and the duration of activity was significantly longer (211 degrees at 0.35BL and 181 degrees at 0.65BL). These results differ from those of previous studies. The results have been used to simulate in vivo activity in isolated muscle preparations using the work loop technique. Preparations from all three locations generated net positive power under in vivo conditions, but the negative power component increased from head to tail. Both kinematically, and in the way its muscle functions to generate hydrodynamic thrust, the rainbow trout appears to be intermediate between anguilliform swimmers such as the eel, which generate thrust along their entire body length, and carangiform fish (e.g. saithe Pollachius virens), which generate thrust primarily at the tail blade.

scholarly journals An Implanted Magnetic Microfluidic Pump for In Vivo Bone Remodeling Applications

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 300 ◽  
Author(s):  
Ziyu Chen ◽  
Sunggi Noh ◽  
Rhonda D. Prisby ◽  
Jeong-Bong Lee
Keyword(s):  
Bone Growth ◽  
Static Pressure ◽  
Dynamic Pressure ◽  
The Body ◽  
In Vivo Studies ◽  
Fischer 344 ◽  
Fischer 344 Rat ◽  
Pressure Modulation

Modulations of fluid flow inside the bone intramedullary cavity has been found to stimulate bone cellular activities and augment bone growth. However, study on the efficacy of the fluid modulation has been limited to external syringe pumps connected to the bone intramedullary cavity through the skin tubing. We report an implantable magnetic microfluidic pump which is suitable for in vivo studies in rodents. A compact microfluidic pump (22 mm diameter, 5 mm in thickness) with NdFeB magnets was fabricated in polydimethylsiloxane (PDMS) using a set of stainless-steel molds. An external actuator with a larger magnet was used to wirelessly actuate the magnetic microfluidic pump. The characterization of the static pressure of the microfluidic pump as a function of size of magnets was assessed. The dynamic pressure of the pump was also characterized to estimate the output of the pump. The magnetic microfluidic pump was implanted into the back of a Fischer-344 rat and connected to the intramedullary cavity of the femur using a tube. On-demand wireless magnetic operation using an actuator outside of the body was found to induce pressure modulation of up to 38 mmHg inside the femoral intramedullary cavity of the rat.

scholarly journals Molecular and functional characterization of somatostatin-type signalling in a deuterostome invertebrate

Open Biology ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 200172
Author(s):  
Ya Zhang ◽  
Luis Alfonso Yañez Guerra ◽  
Michaela Egertová ◽  
Cleidiane G. Zampronio ◽  
Alexandra M. Jones ◽  
...  
Keyword(s):  
Functional Characterization ◽  
The Body ◽  
Pharmacological Characterization ◽  
Cardiac Stomach ◽  
Physiological Processes ◽  
Pharmacological Tests ◽  
The Central Nervous System

Somatostatin (SS) and allatostatin-C (ASTC) are structurally and evolutionarily related neuropeptides that act as inhibitory regulators of physiological processes in mammals and insects, respectively. Here, we report the first molecular and functional characterization of SS/ASTC-type signalling in a deuterostome invertebrate—the starfish Asterias rubens (phylum Echinodermata). Two SS/ASTC-type precursors were identified in A. rubens (ArSSP1 and ArSSP2) and the structures of neuropeptides derived from these proteins (ArSS1 and ArSS2) were analysed using mass spectrometry. Pharmacological characterization of three cloned A. rubens SS/ASTC-type receptors (ArSSR1–3) revealed that ArSS2, but not ArSS1, acts as a ligand for all three receptors. Analysis of ArSS2 expression in A. rubens using mRNA in situ hybridization and immunohistochemistry revealed stained cells/fibres in the central nervous system, the digestive system (e.g. cardiac stomach) and the body wall and its appendages (e.g. tube feet). Furthermore, in vitro pharmacological tests revealed that ArSS2 causes dose-dependent relaxation of tube foot and cardiac stomach preparations, while injection of ArSS2 in vivo causes partial eversion of the cardiac stomach. Our findings provide new insights into the molecular evolution of SS/ASTC-type signalling in the animal kingdom and reveal an ancient role of SS-type neuropeptides as inhibitory regulators of muscle contractility.

scholarly journals Characterizing Behavioral Activity Rhythms in Older Adults Using Actigraphy

Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 549
Author(s):  
Ariel B. Neikrug ◽  
Ivy Y. Chen ◽  
Jake R. Palmer ◽  
Susan M. McCurry ◽  
Michael Von Korff ◽  
...  
Keyword(s):  
Older Adults ◽  
Older Adult ◽  
Activity Patterns ◽  
Additive Models ◽  
Behavioral Activity ◽  
New Approach ◽  
Activity Rhythms ◽  
Activity Measurements ◽  
Wrist Actigraphy

Wrist actigraphy has been used to assess sleep in older adult populations for nearly half a century. Over the years, the continuous raw activity data derived from actigraphy has been used for the characterization of factors beyond sleep/wake such as physical activity patterns and circadian rhythms. Behavioral activity rhythms (BAR) are useful to describe individual daily behavioral patterns beyond sleep and wake, which represent important and meaningful clinical outcomes. This paper reviews common rhythmometric approaches and summarizes the available data from the use of these different approaches in older adult populations. We further consider a new approach developed in our laboratory designed to provide graphical characterization of BAR for the observed behavioral phenomenon of activity patterns across time. We illustrate the application of this new approach using actigraphy data collected from a well-characterized sample of older adults (age 60+) with osteoarthritis (OA) pain and insomnia. Generalized additive models (GAM) were implemented to fit smoothed nonlinear curves to log-transformed aggregated actigraphy-derived activity measurements. This approach demonstrated an overall strong model fit (R2 = 0.82, SD = 0.09) and was able to provide meaningful outcome measures allowing for graphical and parameterized characterization of the observed activity patterns within this sample.

scholarly journals Advanced characterizations of nanoparticles for drug delivery: investigating their properties through the techniques used in their evaluations

2017 ◽  
Vol 6 (4) ◽  
pp. 355-372 ◽  
Author(s):  
Syed Mahmood ◽  
Uttam Kumar Mandal ◽  
Bappaditya Chatterjee ◽  
Muhammad Taher
Keyword(s):  
Drug Delivery ◽  
Advanced Characterization ◽  
Data Interpretation ◽  
Review Article ◽  
The Body ◽  
Drug Molecule ◽  
Drug Molecules ◽  
Preparation Techniques

AbstractNanomedicine has achieved a huge success in delivering a wide variety of drug molecules into the target site of the body. In this respect, the characterization of nanoformulation is very important to investigate the drug molecule together with its carrier as a nanoform during formulation, storage, and in vivo transport through the body. This review article summarizes important advanced characterization techniques of nanoformulation with respect to their theories, use of required instrumental parameters, sample preparation techniques, data interpretation, etc., to exploit them for the best possible results. This review article also sheds a glimpse to the shortcomings of these techniques together with further advancements required in future.

scholarly journals ARTIFICIAL NEURAL NETWORKS BASED SLEEP MOTION RECOGNITION USING NIGHT VISION CAMERAS

2004 ◽  
Vol 16 (02) ◽  
pp. 79-86 ◽  
Author(s):  
CHUNG-HSIEN KUO ◽  
FANG-CHUNG YANG ◽  
MING-YUAN TSAI ◽  
MING-YIH LEE
Keyword(s):  
Neural Networks ◽  
High Speed ◽  
Body Position ◽  
Body Movement ◽  
The Body ◽  
Night Vision ◽  
Ann Model ◽  
Motion Recognition ◽  
Video Frames ◽  
Artificial Neural

The body movement is one of the most important factors to evaluate the sleep quality. In general, the sleep motion is hardly investigated, and it must take a long time to observe the motion of the patient in terms of a pre-recoded video storage media with high speed playing. This paper proposes an image-based solution to recognize the sleep motions. We use the contact free and IR-based night vision camera to capture the video frames during the sleep of the patient. The video frames are used to recognize the body positions and the body directions such as the “body up”, “body down”, “body right”, and “body left”. In addition to the image processing, the proposed artificial neural network (ANN) sleep motion recognition solution is composed of two neural networks. These two neural networks are organized as in a cascade configuration. The first ANN model is used to identify the body position features from the images; and the follower ANN model is constructed based on the features that are identified by the first ANN model to recognize the body direction. Finally, the implementations and the practical results of this work are all illustrated in this paper.

scholarly journals Leucine degradation in cell-free extracts of skeletal muscle

1979 ◽  
Vol 178 (2) ◽  
pp. 475-489 ◽  
Author(s):  
R Odessey ◽  
A L Goldberg
Keyword(s):  
Skeletal Muscle ◽  
Competitive Inhibition ◽  
Primary Source ◽  
Mitochondrial Fraction ◽  
The Body ◽  
Oxidative Decarboxylation ◽  
Transaminase Activity ◽  
Leucine Oxidation ◽  
Activity Measurements

Since skeletal muscle is the major site in the body for oxidation of leucine, isoleucine and valine, the pathway and control of leucine oxidation were investigated in cell-free preparations of rat muscle. Leucine was found to be transaminated to 4-methyl-2-oxopentanoate, which was then oxidatively decarboxylated. On differential centrifugation 70–80% of the transaminase activity was recovered in the soluble fraction of the cell, and the remaining amount in the mitochondrial fraction. The transaminase, from both fractions had similar pH optima and both were markedly inhibited by Ca2+. Thus changes in cellular Ca2+ concentration may regulate transaminase activity. Both transaminases had a much higher affinity for 2-oxoglutarate than for pyruvate. Therefore the utilization of amino groups from leucine for the biosynthesis of alanine in muscle [Odessey, Khairallah & Goldberg (1974) J. Biol. Chem. 249, 7623–7629] in vivo involves transamination with 2-oxoglutarate to produce glutamate, which is then transaminated with pyruvate to produce alanine. The dehydrogenase activity assayed by the decarboxylation of methyl-2-oxo[1-14C]pentanoate was localized exclusively in the fraction containing mitochondria and required NAD+, CoA and thiamin pyrophosphate for optimal activity. Measurements of competitive inhibition suggested that the oxo acids of leucine, isoleucine and valine are all decarboxylated by the same enzyme. The enzyme activity was decreased by 90% upon freezing or sonication and was stimulated severalfold by Mg2+, K+ and phosphate ions. In addition, it was markedly inhibited by ATP, but not by non-metabolizable analogues. This observation suggests that splitting of ATP is required for inhibition. The oxidative decarboxylation of 4-methyl-2-oxopentanoate by the dehydrogenase appears to be the rate-limiting step for leucine oxidation in muscle homogenates and also in intact tissues. In fact, rat muscles incubated with [1-14C]leucine release 1-14C-labelled oxo acid into the medium at rates comparable with the rate of decarboxylation. Intact muscles also released the oxo acids of [1-14C]valine or [1-14C]isoleucine, but not of other amino acids. These findings suggest that muscle is the primary source of the branched-chain oxo acids found in the blood.

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