α-Motoneurons maintain biophysical heterogeneity in obesity and diabetes in Zucker rats

Small-diameter sensory dysfunction resulting from diabetes has received much attention in the literature, whereas the impact of diabetes on α-motoneurons (MN) has not. In addition, the chance of developing insulin resistance and diabetes is increased in obesity. No study has examined the impact of obesity or diabetes on the biophysical properties of MN. Lean Zucker rats and Zucker diabetic fatty (ZDF) rats were separated into lean, obese (ZDF fed standard chow), and diabetic (ZDF fed high-fat diet that led to diabetes) groups. Glass micropipettes recorded hindlimb MN properties from identified flexor and extensor MN. MN were separated within their groups on the basis of input conductance, which created high- and low-input conductance subpopulations for each. A significant shorter (20%) afterhyperpolarization half-decay (AHP1/2) was found in low-conductance MN for the diabetic group only, whereas AHP½ tended to be shorter in the obese group (19%). Significant positive correlations were found among rheobase and input conductance for both lean and obese animals. No differences were found between the groups for afterhyperpolarization amplitude (AHPamp), input conductance, rheobase, or any of the rhythmic firing properties (frequency-current slope and spike-frequency adaptation index). MN properties continue to be heterogeneous in obese and diabetic animals. Obesity does not seem to influence lumbar MN. Despite the resistance of MN to the impact of diabetes, the reduced AHP1/2 decay and the tendency for a reduction in AHPamp may be the first sign of change to MN function. NEW & NOTEWORTHY Knowledge about the impact of obesity and diabetes on the biophysical properties of motoneurons is lacking. We found that diabetes reduces the duration of the afterhyperpolarization and that motoneuron function is unchanged by obesity. A reduced afterhyperpolarization may impact discharge characteristics and may be the first sign of change to motoneuron function.

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Natural Experiment on Trade and Investment Liberalization and Soft Drink Consumption

European Journal of Public Health ◽

10.1093/eurpub/ckaa165.359 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

Y Tcholakov

Keyword(s):

Public Health ◽

International Trade ◽

Natural Experiment ◽

Soft Drink ◽

Trade Agreement ◽

P Value ◽

Soft Drink Consumption ◽

Obesity And Diabetes ◽

Wide Range ◽

The Impact

Abstract Background Globalization is recognized to as a contributing factor to a health harming environment through a variety of mechanisms including through changes in food systems and food availability. Sugar-sweetened beverage (SSB) consumption is linked to obesity and diabetes and its regulation is a key priority for public health. The Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) is an international trade agreement between 11 countries. Methods This project uses of natural experiment methods to predict the impact of the entry into force of the CPTPP on SSB consumption. These methods allow quantitative inferences to be drawn in the situations where the exposure is not randomly assigned. Soft drink consumption data was collected from the Euromonitor database for 80 countries from all regions. This data was used to estimate the effect of agreements similar to the TPP. Results Eleven country trade agreement pairs were identified. In 5 cases out of the 11, the exposed country had a higher soft drink consumption at five years after the trade agreement. The effect of the trade agreement exposure for an average country in the sample in a trade agreement was found to be 1.10 (95% CI: 1.01-1.18; p-value: 0.03) after adjusting for GDP and the involvement of the US. In 7 of the 11 member-countries soft drink consumption is expected to increase yielding an average increase of 9.0% in those countries; the changes did not yield statistically significant differences in others. Conclusions This projected extended the use of synthetic methods to the projection of future effects of policy implementation. While it showed that there may be increasing trend of SSB consumption in certain scenarios, this could not be generalized to all cases. This illustrates the wide range of effects of international trade liberalization and highlights that national policy probably plays a strong modulating role on the impact that it has on local food environments. Key messages Globalization can lead to health harming environments and its impacts should further be studied by public health professionals and researchers. Many global policies have the potential to lead to significant health impacts but are negotiated without involving public health experts.

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Elastic Modulus and Elasticity Ratio of Malignant Breast Lesions with Shear Wave Ultrasound Elastography: Variations with Different Region of Interest and Lesion Size

Diagnostics ◽

10.3390/diagnostics11061015 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1015

Author(s):

Antonio Bulum ◽

Gordana Ivanac ◽

Eugen Divjak ◽

Iva Biondić Špoljar ◽

Martina Džoić Dominković ◽

...

Keyword(s):

Elastic Modulus ◽

Shear Wave ◽

Large Diameter ◽

Small Diameter ◽

Shear Wave Elastography ◽

Lesion Size ◽

Ultrasound Elastography ◽

Breast Lesions ◽

Malignant Breast ◽

The Impact

Shear wave elastography (SWE) is a type of ultrasound elastography with which the elastic properties of breast tissues can be quantitatively assessed. The purpose of this study was to determine the impact of different regions of interest (ROI) and lesion size on the performance of SWE in differentiating malignant breast lesions. The study included 150 female patients with histopathologically confirmed malignant breast lesions. Minimal (Emin), mean (Emean), maximal (Emax) elastic modulus and elasticity ratio (e-ratio) values were measured using a circular ROI size of 2, 4 and 6 mm diameters and the lesions were divided into large (diameter ≥ 15 mm) and small (diameter < 15 mm). Highest Emin, Emean and e-ratio values and lowest variability were observed when using the 2 mm ROI. Emax values did not differ between different ROI sizes. Larger lesions had significantly higher Emean and Emax values, but there was no difference in e-ratio values between lesions of different sizes. In conclusion, when measuring the Emin, Emean and e-ratio of malignant breast lesions using SWE the smallest possible ROI size should be used regardless of lesion size. ROI size has no impact on Emax values while lesion size has no impact on e-ratio values.

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Computer Simulation of the Responses of Human Motoneurons to Composite 1A EPSPS: Effects of Background Firing Rate

Journal of Neurophysiology ◽

10.1152/jn.1997.77.1.405 ◽

1997 ◽

Vol 77 (1) ◽

pp. 405-420 ◽

Cited By ~ 36

Author(s):

Kelvin E. Jones ◽

Parveen Bawa

Keyword(s):

Computer Simulation ◽

Firing Rate ◽

Time Course ◽

Current Model ◽

Response Probability ◽

Muscle Spindles ◽

Excitatory Postsynaptic Potential ◽

Biophysical Properties ◽

Rhythmic Firing ◽

The Relationship

Jones, Kelvin E. and Parveen Bawa. Computer simulation of the responses of human motoneurons to composite 1A EPSPS: effects of background firing rate. J. Neurophysiol. 77: 405–420, 1997. Two compartmental models of spinal alpha motoneurons were constructed to explore the relationship between background firing rate and response to an excitatory input. The results of these simulations were compared with previous results obtained from human motoneurons and discussed in relation to the current model for repetitively firing human motoneurons. The morphologies and cable parameters of the models were based on two type-identified cat motoneurons previously reported in the literature. Each model included five voltage-dependent channels that were modeled using Hodgkin-Huxley formalism. These included fast Na+ and K+ channels in the initial segment and fast Na+ and K+ channels as well as a slow K+ channel in the soma compartment. The density and rate factors for the slow K+ channel were varied until the models could reproduce single spike AHP parameters for type-identified motoneurons in the cat. Excitatory synaptic conductances were distributed along the equivalent dendrites with the same density described for la synapses from muscle spindles to type-identified cat motoneurons. Simultaneous activation of all synapses on the dendrite resulted in a large compound excitatory postsynaptic potential (EPSP). Brief depolarizing pulses injected into a compartment of the equivalent dendrite resulted in pulse potentials (PPs), which resembled the compound EPSPs. The effects of compound EPSPs and PPs on firing probability of the two motoneuron models were examined during rhythmic firing. Peristimulus time histograms, constructed between the stimulus and the spikes of the model motoneuron, showed excitatory peaks whose integrated time course approximated the time course of the underlying EPSP or PP as has been shown in cat motoneurons. The excitatory peaks were quantified in terms of response probability, and the relationship between background firing rate and response probability was explored. As in real human motoneurons, the models exhibited an inverse relationship between response probability and background firing rate. The biophysical properties responsible for the relationship between response probability and firing rate included the shapes of the membrane voltage trajectories between spikes and nonlinear changes in PP amplitude during the interspike interval at different firing rates. The results from these simulations suggest that the relationship between response probability and background firing rate is an intrinsic feature of motoneurons. The similarity of the results from the models, which were based on the properties of cat motoneurons, and those from human motoneurons suggests that the biophysical properties governing rhythmic firing in human motoneurons are similar to those of the cat.

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Characterization of pasture biophysical properties and the impact of grazing intensity using remotely sensed data

Remote Sensing of Environment ◽

10.1016/j.rse.2007.01.013 ◽

2007 ◽

Vol 109 (3) ◽

pp. 314-327 ◽

Cited By ~ 82

Author(s):

Izaya Numata ◽

Dar A. Roberts ◽

Oliver A. Chadwick ◽

Josh Schimel ◽

Fernando R. Sampaio ◽

...

Keyword(s):

Grazing Intensity ◽

Remotely Sensed ◽

Biophysical Properties ◽

Remotely Sensed Data ◽

The Impact

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An Investigation of the Vibration Testing Method for Small Diameter Endmills

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.625.134 ◽

2014 ◽

Vol 625 ◽

pp. 134-139

Author(s):

Takenori Ono

Keyword(s):

Small Diameter ◽

Milling Process ◽

Modal Parameters ◽

Vibration Testing ◽

Function Generator ◽

Testing Method ◽

Milling Tool ◽

Compliance Curve ◽

Vibration Tests ◽

The Impact

This paper introduced about the in-process vibration testing method for small diameter endmill. By this method, the natural frequency and modal parameters such as mass, damping, and stiffness of the milling tool can be determined in the milling process. An oscillation of the vibrator is controlled by the function generator to apply the impact force at the appropriate cutting period. The measurement setup can determine the compliance curve by the measurement signals of the exiting force and tool deformation. To evaluate the feasibility of the new method, vibration tests were performed on a square endmill which has the diameter of 4 mm in the milling on brass material. Results of vibration tests show that modal parameters of the specific vibration mode can be determined by the new developed method.

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A cafeteria diet triggers intestinal inflammation and oxidative stress in obese rats

British Journal Of Nutrition ◽

10.1017/s0007114516004608 ◽

2017 ◽

Vol 117 (2) ◽

pp. 218-229 ◽

Cited By ~ 18

Author(s):

K. Gil-Cardoso ◽

I. Ginés ◽

M. Pinent ◽

A. Ardévol ◽

X. Terra ◽

...

Keyword(s):

Oxidative Stress ◽

Intestinal Inflammation ◽

Cafeteria Diet ◽

Zucker Rats ◽

Standard Diet ◽

Metabolic Alterations ◽

Genetic Obesity ◽

Obesogenic Diet ◽

The Impact ◽

And Oxidative Stress

AbstractThe gastrointestinal alterations associated with the consumption of an obesogenic diet, such as inflammation, permeability impairment and oxidative stress, have been poorly explored in both diet-induced obesity (DIO) and genetic obesity. The aim of the present study was to examine the impact of an obesogenic diet on the gut health status of DIO rats in comparison with the Zucker (fa/fa) rat leptin receptor-deficient model of genetic obesity over time. For this purpose, female Wistar rats (n 48) were administered a standard or a cafeteria diet (CAF diet) for 12, 14·5 or 17 weeks and were compared with fa/fa Zucker rats fed a standard diet for 10 weeks. Morphometric variables, plasma biochemical parameters, myeloperoxidase (MPO) activity and reactive oxygen species (ROS) levels in the ileum were assessed, as well as the expressions of proinflammatory genes (TNF-α and inducible nitric oxide synthase (iNOS)) and intestinal permeability genes (zonula occludens-1, claudin-1 and occludin). Both the nutritional model and the genetic obesity model showed increased body weight and metabolic alterations at the final time point. An increase in intestinal ROS production and MPO activity was observed in the gastrointestinal tracts of rats fed a CAF diet but not in the genetic obesity model. TNF-α was overexpressed in the ileum of both CAF diet and fa/fa groups, and ileal inflammation was associated with the degree of obesity and metabolic alterations. Interestingly, the 17-week CAF group and the fa/fa rats exhibited alterations in the expressions of permeability genes. Relevantly, in the hyperlipidic refined sugar diet model of obesity, the responses to chronic energy overload led to time-dependent increases in gut inflammation and oxidative stress.

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Effect of Common Anesthetics on Dendritic Properties in Layer 5 Neocortical Pyramidal Neurons

Journal of Neurophysiology ◽

10.1152/jn.01126.2007 ◽

2008 ◽

Vol 99 (3) ◽

pp. 1394-1407 ◽

Cited By ~ 28

Author(s):

Sarah Potez ◽

Matthew E. Larkum

Keyword(s):

High Frequency ◽

Pyramidal Neurons ◽

Animal Experiments ◽

Apical Dendrite ◽

Network Activity ◽

Calcium Spikes ◽

Firing Properties ◽

The Impact

Understanding the impact of active dendritic properties on network activity in vivo has so far been restricted to studies in anesthetized animals. However, to date no study has been made to determine the direct effect of the anesthetics themselves on dendritic properties. Here, we investigated the effects of three types of anesthetics commonly used for animal experiments (urethane, pentobarbital and ketamine/xylazine). We investigated the generation of calcium spikes, the propagation of action potentials (APs) along the apical dendrite and the somatic firing properties in the presence of anesthetics in vitro using dual somatodendritic whole cell recordings. Calcium spikes were evoked with dendritic current injection and high-frequency trains of APs at the soma. Surprisingly, we found that the direct actions of anesthetics on calcium spikes were very different. Two anesthetics (urethane and pentobarbital) suppressed dendritic calcium spikes in vitro, whereas a mixture of ketamine and xylazine enhanced them. Propagation of spikes along the dendrite was not significantly affected by any of the anesthetics but there were various changes in somatic firing properties that were highly dependent on the anesthetic. Last, we examined the effects of anesthetics on calcium spike initiation and duration in vivo using high-frequency trains of APs generated at the cell body. We found the same anesthetic-dependent direct effects in addition to an overall reduction in dendritic excitability in anesthetized rats with all three anesthetics compared with the slice preparation.

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Abstract 328: Hemodynamic Comparison of Zucker Diabetic Fatty Rats to Their Lean Littermates After Asphyxial Cardiac Arrest

Circulation ◽

10.1161/circ.138.suppl_2.328 ◽

2018 ◽

Vol 138 (Suppl_2) ◽

Author(s):

Claudius Balzer ◽

Franz Baudenbacher ◽

Michele M Salzman ◽

William J Cleveland ◽

Susan Eagle ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Cardiac Arrest ◽

Ejection Fraction ◽

Ischemia Reperfusion ◽

Diabetic Rats ◽

Arterial Blood ◽

Zucker Diabetic Fatty Rats ◽

Zdf Rats ◽

The Impact

Patients with metabolic syndrome are at higher risk for cardiac arrest (CA), and also have worse neurologic outcome after CA related to their comorbidities (e.g., Type 2 Diabetes Mellitus [T2DM]). Using Zucker Diabetic Fatty (ZDF) rats as a new and relevant model with common comorbidities for CA and cardiopulmonary resuscitation (CPR), we hypothesized that T2DM is associated with a lower chance for return of spontaneous circulation (ROSC) and/or a worse outcome regarding heart function after asphyxial CA compared to their lean littermates. Two groups of rats (8 ZDF, 7 lean) were monitored for 37±2 weeks. The rats were anesthetized and intubated; heart rate was monitored by subcutaneous ECG needles. Femoral artery and vein were cannulated for continuous blood pressure measurement and delivery of fluids and medications, respectively. Before ventilation was stopped to initiate asphyxial CA, rocuronium was given. After 8 minutes of CA, ventilation was re-initiated with FiO 2 1.0, epinephrine and sodium-bicarbonate were administered, and pneumatic chest compression were started with 200 compressions per minute. Chest compressions were stopped when a systolic blood pressure of 120 mmHg was achieved. During 4 hours of observation, vital parameters were closely monitored, blood gases were measured, and ejection fraction (EF %) was assessed with ultrasound. Data are mean ± SD. Statistics: Unpaired student’s t-test (two-tailed), α.05. At baseline, ZDF rats showed significantly higher blood glucose levels (504±52 vs 174±14 mg/dl) compared to their lean littermates. All ZDF and lean rats achieved ROSC, and measurements taken directly after ROSC and after the first hour showed no relevant differences. After four hours, there was no difference in heart rate between ZDF and lean rats. However, diabetic rats had a significantly higher mean arterial blood pressure (142±24vs. 107±19 mmHg) and ejection fraction (42±16%vs 20±8%) compared to their lean littermates. The hypothesis that ROSC-rate in diabetic rats would be lower could not be proven. Conversely, the ZDF rats showed a significantly higher blood pressure related to an increased EF%. Further analysis in this study will focus on the impact of T2DM on cardiac and neurological ischemia-reperfusion injury.

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Impact of Tracheal Tube on Swallowing in Post-Operative Head and Neck Cancer Patients: Scintigraphic Analysis

Dysphagia ◽

10.1007/s00455-020-10222-y ◽

2020 ◽

Author(s):

Jacopo Galli ◽

Maria Raffaella Marchese ◽

Tiziana Di Cesare ◽

Laura Tricarico ◽

Giovanni Almadori ◽

...

Keyword(s):

Head And Neck Cancer ◽

Head And Neck ◽

Cancer Patients ◽

Tracheal Tube ◽

Transit Time ◽

Neck Cancer ◽

Retention Index ◽

Small Diameter ◽

Swallowing Rehabilitation ◽

The Impact

AbstractDysphagia is common in tracheostomized patients who underwent head and neck surgery for cancer treatment. The objective of this study was to evaluate, by means of oropharyngoesophageal scintigraphy (OPES), the impact of an occluded tracheal tube (TT) on swallowing in patients treated for head and neck cancer before hospital discharge, to provide further information to the benefit of out-patient care management. From October 2018 to November 2019, we enrolled 19 tracheostomized patients (6 females and 13 males; mean age 61 years) who underwent primary surgical resection of head and neck tumor and swallowing rehabilitation during hospitalization. All subjects underwent a double-standard OPES, one with occluded tracheal tube and the other without TT, with their tracheal stoma being closed directly by a plaster. For each study, we assessed and compared the following quantitative parameters: oral transit time (OTTsec), pharyngeal transit time (PTTsec), esophageal transit time (ETTsec), oral retention index (ORI%), pharyngeal retention index (PRI%), esophageal retention index (ERI%), and aspiration percentage (AP%). The mean values of OTT, PTT, ORI%, PRI%, and ERI% were abnormal during OPES both with TT and without TT and did not statistically differ between the two tests (p > 0.05). Aspiration was detected in 4 cases out of 19 (21.05%) cases during OPES with TT and in 4/19 (21.05%) cases without TT who showed a mean AP% of 11.4% and 11.5% respectively (p > 0.05). Patients with abnormal AP% (> 0%) during OPES with TT showed aspiration signs without TT. Our study showed that the mere presence of a closed tracheal tube does not impact significantly the oropharyngeal transit of bolus during swallowing. This result suggests the possibility to maintain a small-diameter occluded tracheal tube in place for the postsurgical management of head and neck cancer patients.

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Simulation of the Impact of Ionized Impurity Scattering on the Total Mobility in Si Nanowire Transistors

Materials ◽

10.3390/ma12010124 ◽

2019 ◽

Vol 12 (1) ◽

pp. 124 ◽

Cited By ~ 13

Author(s):

Toufik Sadi ◽

Cristina Medina-Bailon ◽

Mihail Nedjalkov ◽

Jaehyun Lee ◽

Oves Badami ◽

...

Keyword(s):

Surface Roughness ◽

Small Diameter ◽

Golden Rule ◽

Impurity Scattering ◽

Boltzmann Transport ◽

Nanowire Transistors ◽

Scattering Mechanisms ◽

Relaxation Time Approximation ◽

Ionized Impurity Scattering ◽

The Impact

Nanowire transistors (NWTs) are being considered as possible candidates for replacing FinFETs, especially for CMOS scaling beyond the 5-nm node, due to their better electrostatic integrity. Hence, there is an urgent need to develop reliable simulation methods to provide deeper insight into NWTs’ physics and operation, and unlock the devices’ technological potential. One simulation approach that delivers reliable mobility values at low-field near-equilibrium conditions is the combination of the quantum confinement effects with the semi-classical Boltzmann transport equation, solved within the relaxation time approximation adopting the Kubo–Greenwood (KG) formalism, as implemented in this work. We consider the most relevant scattering mechanisms governing intraband and multi-subband transitions in NWTs, including phonon, surface roughness and ionized impurity scattering, whose rates have been calculated directly from the Fermi’s Golden rule. In this paper, we couple multi-slice Poisson–Schrödinger solutions to the KG method to analyze the impact of various scattering mechanisms on the mobility of small diameter nanowire transistors. As demonstrated here, phonon and surface roughness scattering are strong mobility-limiting mechanisms in NWTs. However, scattering from ionized impurities has proved to be another important mobility-limiting mechanism, being mandatory for inclusion when simulating realistic and doped nanostructures, due to the short range Coulomb interaction with the carriers. We also illustrate the impact of the nanowire geometry, highlighting the advantage of using circular over square cross section shapes.

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