Search results for "peripheral nerve"

The role of exercise on peripheral nerve regeneration: from animal model to clinical application

2021

Peripheral nerve injury is a complex condition with a variety of signs and symptoms depending on the severity and nerves involved. Peripheral nerve damage may lead to sensory and motor functions deficits and even lifelong disability, causing important socioeconomic costs worldwide. Despite the increase in knowledge of the mechanisms of injury and regeneration, a full functional recovery is still unsatisfying in the majority of patients. It is well known that exercise promotes physical and psychological well-being, by ameliorating general health. In the last years, there has been a growing interest in evaluating the effects of exercise on the peripheral nervous system. Experimental works wit…

158 Timing of Fascia Iliaca Compartment Block (FICB) for Neck of Femur (NOF) fracture in the Accident and Emergency Department (AED) and the operatin…

2021

Background and Aims FICB is recommended for NOF fracture in the AED to improve analgesia1 and as an adjuvant to anaesthesia during surgery2. Surgical repair of the fracture should be performed on the day of, or the day after, admission3. We evaluated the provision of FICB in AED and its potential to cause local anaesthetic (LA) toxicity when followed by a further block at time of surgery. Methods All patients admitted to our institution with NOF fracture during October 2019 were retrospectively screened for FICBs. We recorded the time of: admission, FICB in AED, surgery, FICB in theatre and LA dose. Data was cross-referenced and validated against National Hip Fracture Database (NHFD) tables…

Prospective evaluation of intraoperative peripheral nerve injury in colorectal surgery

2012

Aim  Intraoperative peripheral nerve injury can have permanent neurological consequences. Its incidence is not known and varies according to the location and the surgical specialty. This study was a prospective analysis of intraoperative peripheral nerve injury as a complication of abdominal colorectal surgery. Method  All patients who underwent major colorectal abdominal surgery in our Colorectal Unit between 1996 and 2009 were analyzed. Data on nerve injury were prospectively collected. Results  There were 2304 patients, of whom eight (0.3%) experienced intraoperative peripheral nerve injury. This occurred in 5/2211 (0.2%) open procedures and in 3/93 (3%) laparoscopic procedures. There wa…

Injured Axons Instruct Schwann Cells to Build Constricting Actin Spheres to Accelerate Axonal Disintegration

2019

Summary: After a peripheral nerve lesion, distal ends of injured axons disintegrate into small fragments that are subsequently cleared by Schwann cells and later by macrophages. Axonal debris clearing is an early step of the repair process that facilitates regeneration. We show here that Schwann cells promote distal cut axon disintegration for timely clearing. By combining cell-based and in vivo models of nerve lesion with mouse genetics, we show that this mechanism is induced by distal cut axons, which signal to Schwann cells through PlGF mediating the activation and upregulation of VEGFR1 in Schwann cells. In turn, VEGFR1 activates Pak1, leading to the formation of constricting actomyosin…

SETD7 mediates spinal microgliosis and neuropathic pain in a rat model of peripheral nerve injury

2019

Abstract Gene transcription regulation is critical for the development of spinal microgliosis and neuropathic pain after peripheral nerve injury. Using a model of chronic constriction injury (CCI) of the sciatic nerve, this study characterized the role of SET domain containing lysine methyltransferase 7 (SETD7) which monomethylates histone H3 lysine 4 (H3K4me1), a marker for active gene transcription. SETD7 protein expression in the spinal dorsal horn ipsilateral to nerve lesion was increased from one day to 14 days after CCI, concomitantly with the expression of inflammatory genes, Ccl2, Il-6 and Il-1β. The CCI-induced SETD7 expression was predominantly localized to microglia, as demonstra…

Pancreatic polypeptide stimulates mouse gastric motor activity through peripheral neural mechanisms

2016

Background Pancreatic polypeptide (PP) is supposed to be one of the major endogenous agonists of the neuropeptide Y4 receptor. Pancreatic polypeptide can influence gastrointestinal motility, acting mainly through vagal mechanisms, but whether PP acts directly on the stomach has not been explored yet. The aims of this study were to investigate the effects of PP on mouse gastric emptying, on spontaneous tone of whole stomach in vitro and to examine the mechanism of action. Methods Gastric emptying was measured by red phenol method after i.p. PP administration (1–3 nmol per mouse). Responses induced by PP (1–300 mmol L−1) on gastric endoluminal pressure were analyzed in vitro in the presence o…

Changes of the ratio between myelin thickness and axon diameter in human developing sural, femoral, ulnar, facial, and trochlear nerves

1988

Previous studies on sural nerves were extended to human femoral, ulnar, facial and trochlear nerves. As asynchronous development of axon diameter and myelin sheath thickness was noted in all nerves studied. Whereas axons reach their maximal diameter by or before 5 years of age, maximal myelin sheath thickness is not attained before 16-17 years of age, i.e., more than 10 years later. The slope of the regression lines for the ratio between axon diameter and myelin thickness is significantly steeper in older than in younger individuals; it also differs if small and large fibers with more or less than 50 myelin lamellae are evaluated separately. The number of Schmidt-Lanterman incisures during …

Alterations in the antioxidant defense of peripheral nervous tissue following acute ethanol administration

1993

Giant axonal neuropathy and leukodystrophy

1991

Abstract An 11-year-old Persian boy, born to consanguineous parents, manifested a progressive gait abnormality beginning at 5 years of age. A severe cerebellar disorder developed with associated dysfunction of the peripheral nervous system, but no sign of mental impairment. The sensory and motor nerve conduction velocities were greatly reduced, especially in the lower extremities. Cerebrospinal fluid protein was normal. Computed tomography and magnetic resonance imaging revealed leukoencephalopathy, especially in the cerebellum, but also in periventricular areas. The diagnosis of giant axonal neuropathy was established by biopsy of the sural nerve. The few previous histologic examinations h…

Doublet potentiation in the triceps surae is limited by series compliance and dynamic fascicle behavior.

2015

Activation of skeletal muscle twice in quick succession results in nonlinear force summation (i.e., doublet potentiation). The force contributed by a second activation is typically of augmented amplitude, longer in duration, and generated at a greater rate. The purpose of this study was to examine force summation in a muscle attached to a compliant tendon, where considerable internal shortening occurs during a fixed-end contraction. The triceps surae of 21 ( Experiment 1) and 9 ( Experiment 2) young adults were maximally activated with doublet stimulation of different interstimulus intervals (ISIs) (5-100 ms) at several muscle lengths. Ultrasound images acquired from lateral gastrocnemius …