In vitro effects of hydrogen peroxide on rat uterine contraction before and during pregnancy

Aim To assess the in vitro effect of hydrogen peroxide (H2O2) on uterine contractions in pregnant and non-pregnant rats. Methods The study was performed at the Department of Physiology, College of Medicine, King Saud University from December 2016 to October 2017. Intact uterine samples were obtained from non-pregnant (n = 7-8) and termpregnant (n = 6-7) rats. Small longitudinal uterine strips were dissected and mounted in an organ bath. Isometric force measurements were used to assess the effect of 400, 800, and 1000 μM H2O2 on spontaneous uterine contractions and contractions induced by oxytocin (5 nM), high calcium (Ca+2) solution (6 mmol/L), and high potassium chloride (KCl) solution (60 mmol/L).Results In both term-pregnant and non-pregnant uterine strips, H2O2 elicited a biphasic response, consisting of a transient contraction followed by a persistent decrease in spontaneously generated contractions, contractions induced by oxytocin, and contractions induced by high Ca+2 (all P < 0.01, compared with controls) in a concentration-dependent manner. The effect of H2O2 was more pronounced in non-pregnant than in pregnant rats (P < 0.05). In both groups, H2O2 failed to relax uterine strips pre-contracted with high-KCl solution (P > 0.05 compared with controls). Conclusion H2O2 was shown to be a potent uterine relaxant in pregnant and non-pregnant states. The pregnant uterus better withstood the inhibitory effect of H2O2 than non-pregnant uterus

Intense isolectin-B4 binding in rat dorsal root ganglion neurons distinguishes c-fiber nociceptors with broad action potentials and high nav1.9 expression

Binding to isolectin-B4 (IB4) and expression of tyrosine kinase A (trkA) (the high-affinity NGF receptor) have been used to define two different subgroups of nociceptive small dorsal root ganglion (DRG) neurons. We previously showed that only nociceptors have high trkA levels. However, information about sensory and electrophysiological properties in vivo of single identified IB4-binding neurons, and about their trkA expression levels, is lacking. IB4-positive (IB4+) and small dark neurons had similar size distributions. We examined IB4-binding levels in >120 dye-injected DRG neurons with sensory and electrophysiological properties recorded in vivo. Relative immunointensities for trkA and two TTX-resistant sodium channels (Nav1.8 and Nav1.9) were also measured in these neurons. IB4+ neurons were classified as strongly or weakly IB4+. All strongly IB4+ neurons were C-nociceptor type (C-fiber nociceptive or unresponsive). Of 32 C-nociceptor-type neurons examined, ~50% were strongly IB4+, ~20% were weakly IB4+ and ~30% were IB4–. A{delta} low-threshold mechanoreceptive (LTM) neurons were weakly IB4+ or IB4–. All 33 A-fiber nociceptors and all 44 A{alpha}/beta-LTM neurons examined were IB4–. IB4+ compared with IB4– C-nociceptor-type neurons had longer somatic action potential durations and rise times, slower conduction velocities, more negative membrane potentials, and greater immunointensities for Nav1.9 but not Nav1.8. Immunointensities of IB4 binding in C-neurons were positively correlated with those of Nav1.9 but not Nav1.8. Of 23 C-neurons tested for both trkA and IB4, ~35% were trkA+/IB4+ but with negatively correlated immunointensities; 26% were IB4+/trkA–, and 35% were IB4–/trkA+. We conclude that strongly IB4+ DRG neurons are exclusively C-nociceptor type and that high Nav1.9 expression may contribute to their distinct membrane properties

Evaluation of rheological performance of a local modified bitumen by Styrene Butadiene Styrene polymer used in wearing course

In road construction, bitumen is the binder that gathered the different aggregates of road pavements. Bitumen, as a viscoelastic material, influences considerably the rheological behavior of bitumen concrete. The bitumen used in Algeria, showed its limits face to the traffic, which is increasing continuously. This research aims to valorize SBS polymer in wearing course by modifying a pure 35/50 bitumen. The present paper aims to study the polymer derived from styrene and butadiene (SBS) from the company Kraton Polymers International Ltd in the modification of a bitumen to improve its mechanical characteristics.To this end, the incorporation of SBS polymer was carried out according to two contents: 5.0 and 7.5% (by weight of asphalt), the objective being to evaluate the influence of this type of polymer on the rheological properties of the bitumen ordinary road including viscosity and modulus.The results reveal that the bitumen modified with 7.5% of SBS has better mechanical performance on the rigidity and the elasticity compared to the conventional bitumen. Recommendations have been made to implement a bitumen modification system to improve its quality and therefore the durability of bituminous pavements in the south of Algeria

Synergistic activity of sulbactam combined with colistin against colistin-resistant Acinetobacter baumannii

Acinetobacter baumannii is an emerging multidrug-resistant (MDR) pathogen that is responsible for community- and hospital-acquired infections that are difficult to control and treat [1]. With increasing antimicrobial resistance to carbapenems, colistin is often the treatment of last resort, however colistin-resistant clinical isolates have already been reported. Since therapeutic options are very limited or absent in some cases of infection with pandrug-resistant bacteria, there is an urgent need to find new antibiotic strategies

Cutaneous Aβ-Non-nociceptive, but Not C-Nociceptive, Dorsal Root Ganglion Neurons Exhibit Spontaneous Activity in the Streptozotocin Rat Model of Painful Diabetic Neuropathy .

Diabetic peripheral neuropathic pain (DPNP) is the most devastating complication of diabetes mellitus. Unfortunately, successful therapy for DPNP remains a challenge because its pathogenesis is still elusive. However, DPNP is believed to be due partly to abnormal hyperexcitability of dorsal root ganglion (DRG) neurons, but the relative contributions of specific functional subtypes remain largely unknown. Here, using the strepotozotocin (STZ) rat model of DPNP induced by a STZ injection (60 mg/kg, i.p), and intracellular recordings of action potentials (APs) from DRG neurons in anesthetized rats, we examined electrophysiological changes in C-and Aβ-nociceptive and Aβ-low threshold mechanoreceptive (LTM) neurons that may contribute to DPNP. Compared with control, we found in STZ-rats with established pain hypersensitivity (5 weeks post-STZ) several significant changes including: (a) A 23% increase in the incidence of spontaneous activity (SA) in Aβ-LTMs (but not C-mechanosensitive nociceptors) that may cause dysesthesias/paresthesia suffered by DPNP patients, (b) membrane hyperpolarization and a ∼85% reduction in SA rate in Aβ-LTMs by K7 channel activation with retigabine (6 mg/kg, i.v.) suggesting that K7/M channels may be involved in mechanisms of SA generation in Aβ-LTMs, (c) decreases in AP duration and in duration and amplitude of afterhyperpolarization (AHP) in C-and/or Aβ-nociceptors. These faster AP and AHP kinetics may lead to repetitive firing and an increase in afferent input to the CNS and thereby contribute to DPNP development, and (d) a decrease in the electrical thresholds of Aβ-nociceptors that may contribute to their sensitization, and thus to the resulting hypersensitivity associated with DPNP.This research work was supported by a Medical Research Council grant (G0700420) and a Ph.D. studentship from Biotechnology and Biological Sciences Research Council to LD

Proof: How Small Drones Can Find Buried Landmines in the Desert Using Airborne IR Thermography

Hypotheses and speculation have circulated for at least three decades regarding how IR thermography could be viable as a technique for locating buried landmines in arid environments. However, there has been a lack of proof under actual field conditions. Addressing many overall questions regarding small drones in HMA, the Odyssey2025 Project—led by HI and Mobility Robotics— closely collaborated with the national mine action center in Chad, the Haut Commissariat National au Déminage (HCND), to complete activities and objectives. As part of a holistic approach, the primary objective was to determine how small drones could add value in HMA field operations and augment other assets at both simple and advanced perspectives. This research is from an advanced perspective, following on from the work previously published in The Journal of Conventional Weapons Destruction outlining how low-cost consumer drones can augment HMA operations at a simple level using visual imagery and GIS/cartography/photogrammetry. This article aims to advance the field’s understanding of drones and their ability to indicate the location of buried objects

Vectorial Formalism of Polyphase Synchronous Machine With Permanents Magnets

Abstract- This paper presents a mathematical model that transforms the real machine to fictitious machines and our goal is to simulate these and see the behavior of these machines in load. The polyphase machines are developed mainly in the field of variable speed drives of high power because increasing the number of phases on the one hand allows to reduce the dimensions of the components in power modulators energy and secondly to improve the operating safety. By a vector approach (vector space), it is possible to find a set of single-phase machine and / or two-phase fictitious equivalent to polyphase synchronous machine. These fictitious machines are coupled electrically and mechanically but decoupled magnetically. This approach leads to introduce the concept of the equivalent machine (multimachine multiconverter system MMS) which aims to analyze systems composed of multiple machines (or multiple converters) in electric drives. A first classification multimachine multiconverter system follows naturally from MMS formalism. We present an example of a pentaphase (polyphase) synchronous machine for a simulation and study the behavior of the machine load. Keywords: Polyphase machines, multimachine concept, vector space, eigenvectors, eigenvalues, pentaphase machine

Vectorial Formalism of Polyphase Synchronous Machine with Permanents Magnets

- This paper presents a mathematical model that transforms the real machine to fictitious machines and our goal is to simulate these and see the behavior of these machines in load. The polyphase machines are developed mainly in the field of variable speed drives of high power because increasing the number of phases on the one hand allows to reduce the dimensions of the components in power modulators energy and secondly to improve the operating safety. By a vector approach (vector space), it is possible to find a set of single-phase machine and / or two-phase fictitious equivalent to polyphase synchronous machine. These fictitious machines are coupled electrically and mechanically but decoupled magnetically. This approach leads to introduce the concept of the equivalent machine (multimachine multiconverter system MMS) which aims to analyze systems composed of multiple machines (or multiple converters) in electric drives. A first classification multimachine multiconverter system follows naturally from MMS formalism. We present an example of a pentaphase (polyphase) synchronous machine for a simulation and study the behavior of the machine load