Pharmacological blocking of spinal GABA receptors in monkeys reduces sensory transmission to the spinal cord, thalamus, and cortex.

A century of research established that GABA inhibits proprioceptive inputs presynaptically to sculpt spinal neural inputs into skilled motor output. Recent results in mice challenged this theory by showing that GABA can also facilitate action potential conduction in proprioceptive afferents. Here, we tackle this controversy in monkeys, the most human-relevant animal model, and show that GABA receptors (GABARs) indeed facilitate sensory inputs to spinal motoneurons and interneurons and that this mechanism also influences sensory transmission to supraspinal centers.

Phytochemical profiling of leaf extract UHPLC-QTOF-MS/MS with assessment of its antiviral mechanisms.

Among 36 species of the genus (family Palmae or Arecaceae), is considered the only species native to Africa. Previous studies showed the richness of fruits in phenolic compounds. The goal of the current study was to investigate the phytochemical composition and assess the antiviral mechanisms of the leaves' ethanolic extract cultivated in Egypt for the first time.

A NEW POSTURAL MOTOR RESPONSE TO SPINAL CORD STIMULATION: POST-STIMULATION REBOUND EXTENSION.

Spinal cord stimulation (SCS) has emerged as a therapeutic tool for improving motor function following spinal cord injury. While many studies focus on restoring locomotion, little attention is paid to enabling standing which is a prerequisite of walking. In this study, we fully characterize a new type of response to SCS, a long extension activated post-stimulation (LEAP).

GABA Increases Sensory Transmission In Monkeys.

Sensory input flow is central to voluntary movements. For almost a century, GABA was believed to modulate this flow by inhibiting sensory axons in the spinal cord to sculpt neural inputs into skilled motor output. Instead, here we show that GABA can also facilitate sensory transmission in monkeys and consequently increase spinal and cortical neural responses to sensory inputs challenging our understanding of generation and perception of movement.

Muscle Spasms after Spinal Cord Injury Stem from Changes in Motoneuron Excitability and Synaptic Inhibition, Not Synaptic Excitation.

Muscle spasms are common in chronic spinal cord injury (SCI), posing challenges to rehabilitation and daily activities. Pharmacological management of spasms mostly targets suppression of excitatory inputs, an approach known to hinder motor recovery. To identify better targets, we investigated changes in inhibitory and excitatory synaptic inputs to motoneurons as well as motoneuron excitability in chronic SCI.

Fracture Strength of Composite Rest Seats: An In Vitro Comparative Study of Different Composite versus Amalgam Restorations.

Occlusal rest provides support for removable partial dentures (RPD). Rest seats are ideally prepared in enamel, but the abutment teeth might be restored or need restorations. This study compared the fracture strength of abutments restored with composite to amalgam restorations after rest seat preparation.

Hibiscus attenuates renovascular hypertension-induced aortic remodeling dose dependently: the oxidative stress role and Ang II/cyclophilin A/ERK1/2 signaling.

The high levels of angiotensin II (Ang II) can modify the vascular tone, enhance vascular smooth muscle cells (VSMCs) proliferation and hypertrophy and increase the inflammatory cellular infiltration into the vessel wall. The old herbal nonpharmacological agent, Hibiscus (HS) sabdariffa L has multiple cardioprotective impacts; thus, we investigated the role of HS extract in amelioration of renovascular hypertension (RVH)-induced aortic remodeling. Thirty-five rats (7/group) were randomly allocated into 5 groups; group: I: Control-sham group, and RVH groups; II, III, IV, and V.

Knowledge of Saudi dental students and interns towards luting cements and their applications in fixed prosthodontics.

Background: Enhancement of students' knowledge is essential in improving their clinical skills and performance. Thus, the curriculum should be prepared to achieve a better outcome. The current study aimed to determine the dental students' and interns' basic knowledge towards dental luting cements and their application in dental practice to improve the theoretical and clinical training sections.

The Toothbrushing Effects on Surface Properties and Color Stability of CAD/CAM and Pressable Ceramic Fixed Restorations-An In Vitro Study.

Pressable ceramic restorations have been introduced and investigated, and found comparable to CAD/CAM ceramic in terms of mechanical properties; however, the effect of toothbrushing on the pressable ceramic has not been thoroughly investigated. The objective of the current study was to assess the effect of artificial toothbrushing simulation on the surface roughness, microhardness, and color stability of different ceramic materials. Three lithium disilicate-based ceramics (IPS Emax CAD [EC], IPS Emax Press [EP]; (Ivoclar Vivadent AG), and LiSi Press [LP] (GC Corp, Tokyo, Japan)) were examined.

Influence of CAD/CAM Milling and 3D-Printing Fabrication Methods on the Mechanical Properties of 3-Unit Interim Fixed Dental Prosthesis after Thermo-Mechanical Aging Process.

This study assessed the influence of CAD/CAM milling and 3D-printing fabrication methods on mechanical properties of 3-unit interim fixed dental prosthesis (IFDPs) after thermo-mechanical aging. Forty 3-unit IFDPs were fabricated on a mandibular right second premolar and second molar of a typodont cast. Samples were fabricated from the following materials; auto-polymerized polymethyl methacrylate (conventional resin), CAD/CAM PMMA (milled resin) and two different CAD/CAM 3D-printed composite resins; digital light processing Asiga (DLP AS) and stereolithography NextDent (SLA ND).

An Updated Review of Salivary pH Effects on Polymethyl Methacrylate (PMMA)-Based Removable Dental Prostheses.

Salivary pH is a neglected factor that may affect the performance of removable dental prostheses (RDP). This study aimed to review literature in reference to the role of salivary pH on the performance of RDP and materials used for their fabrication. From January 1990 until December 2021, a search was done on PubMed, Scopus, and Web of Science databases using removable dental prostheses, salivary pH, PMMA, Denture base, and physical properties as keywords.

Comparative Study of the Effectiveness of Laboratory-Formulated Polishing Pastes for Two CAD/CAM Ceramic Restorative Materials.

Purpose: To evaluate the effect of different polishing pastes with different particle sizes on the surface finish of two different CAD/CAM ceramics.

Materials And Methods: A total of 128 specimens were prepared of two CAD/CAM ceramics: lithium disilicate (12.4 × 14.

Evaluation of the Accuracy of Digital Impressions Obtained from Intraoral and Extraoral Dental Scanners with Different CAD/CAM Scanning Technologies: An In Vitro Study.

Purpose: To compare the accuracy of intraoral and extraoral scanners (IOSs and EOSs) with different scanning technologies.

Material And Methods: A phantom cast was used to simulate the patient's mouth. Polyether impression was made of the phantom cast and poured to fabricate stone casts.

Translucency of nanoparticle-reinforced PMMA denture base material: An in-vitro comparative study.

The aim of this study was to assess the translucency of denture base acrylic resin reinforced with zirconium dioxide (ZrONPs), silicon dioxide (SiONPs), and diamond (DNPs) nanoparticles. A total of 130 heat-polymerized acrylic discs (15×2.5 mm) were fabricated conventionally and divided into control and experimental groups according to nanoparticle type and concentration (0.

Evaluation of Bacterial Leakage in Platform-Switching Dental Implant with Morse Taper Connection Under Thermocycling and Loading Effects: In Vitro Study.

Purpose: The aim of this study was to test in vitro the bacterial microleakage at the Morse taper implant-abutment connection with switched platform subjected to functional load and thermocycling.

Materials And Methods: A total of 48 Morse taper implant-abutment connections with switched platforms (12 implants per group) were used. The abutments were attached to implants and presented in four groups: group 1, control; group 2, subjected to thermocycling; group 3, subjected to cyclic compressive loading; and group 4, subjected to thermocycling and cyclic compressive loading.

The Mechanistic Basis for Successful Spinal Cord Stimulation to Generate Steady Motor Outputs.

Electrical stimulation of the spinal cord is a promising rehabilitation intervention to restore/augment motor function after spinal cord injury (SCI). Combining sensory feedback with stimulation of remaining motor circuits has been shown to be a prerequisite for the functional improvement of SCI patients. However, little is known about the cellular mechanisms potentially underlying this functional benefit in the injured spinal cord.

Modulation of SK channels regulates locomotor alternating bursting activity in the functionally-mature spinal cord.

The spinal cord contains specialized groups of cells called pattern generators, which are capable of orchestrating rhythmic firing activity in an isolated preparation. Different patterns of activity could be generated in vitro including right-left alternating bursting and bursting in which both sides are synchronized. The cellular and network mechanisms that enable these behaviors are not fully understood.

Comparative chemical and biological studies of leaves and pollens of Phoenix canariensis hort. ex Chabaud.

Aim: Phoenix canariensis hort. ex Chabaud is one of the most important palm plants. In spite of that, it has not been extensively investigated from a phytochemical or a biological perspective.

SK channel inhibition mediates the initiation and amplitude modulation of synchronized burst firing in the spinal cord.

Burst firing in motoneurons represents the basis for generating meaningful movements. Neuromodulators and inhibitory receptor blocker cocktails have been used for years to induce burst firing in vitro; however, the ionic mechanisms in the motoneuron membrane that contribute to burst initiation and amplitude modulation are not fully understood. Small conductance Ca-activated potassium (SK) channels regulate excitatory inputs and firing output of motoneurons and interneurons and therefore, are a candidate for mediating bursting behavior.

In vitro shear bond strength of Y-TZP ceramics to different core materials with the use of three primer/resin cement systems.

Statement Of Problem: Durability of the bond between different core materials and zirconia retainers is an important predictor of the success of a dental prosthesis. Nevertheless, because of its polycrystalline structure, zirconia cannot be etched and bonded to a conventional resin cement.

Purpose: The purpose of this in vitro study was to compare the effects of 3 metal primer/resin cement systems on the shear bond strength (SBS) of 3 core materials bonded to yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) ceramic retainers.