Rough endoplasmic reticulum expansion: a consistent finding in a patient cohort with vascular Ehlers-Danlos Syndrome and Osteogenesis Imperfecta.

Vascular Ehlers-Danlos Syndrome (vEDS) and Osteogenesis Imperfecta (OI) are two forms of connective tissue disorders. Previously, transmission electron microscopy of skin biopsies was routinely performed on all patients who were clinically suspected to have vEDS. At present, molecular genetics using genomic DNA extracted from a blood sample is the first line investigation for these patients.

High bone mass phenotype in a cohort of patients with Osteogenesis Imperfecta caused due to and C-propeptide cleavage variants in .

Objectives: Osteogenesis Imperfecta (OI) is a heterogeneous condition mainly characterised by bone fragility; extra-skeletal features in OI include blue sclerae, dentinogenesis imperfecta, skin laxity and joint hyper-extensibility. Most patients with OI are thought to have a low bone mass but contrary to expectations there are certain forms of OI with high bone mass which this study explores in further detail.

Method: A cohort of n = 6 individuals with pathogenic variants in and the C-propeptide cleavage variants in were included in this study.

Effect of hypnosis on masseter EMG recorded during the 'resting' and a slightly open jaw posture.

The aim of this experimental study was to determine whether minimal levels of electromyographic activity in the masseter muscle are altered when individuals are in a verified hypnotic state. Experiments were performed on 17 volunteer subjects (8 male, 9 female) all of whom gave informed consent. The subjects were dentate and had no symptoms of pain or masticatory dysfunction.

Selective stimulation of human tooth-pulp with a new stable method: responses and validation.

Introduction: The aims of this study were to establish a safe technique for selective stimulation of nerves in human tooth-pulp during long experiments and to validate its use even with stimuli of high intensities.

Methods: A custom-made veneer containing 2 silver wire-conductive cream electrodes was attached with cement to the labial surface of an upper central incisor tooth. A variety of stimulus intensities were applied, and sensory and reflex responses from jaw-closing muscles were recorded.

Forces, movements and reflexes produced by pushing human teeth.

Pushing a tooth results in movement of the tooth and reflex inhibition of activity in jaw-closing muscles. The aims of this study were to determine how much tooth movement is required to elicit such reflexes and whether this is dependent on the point of force application to the tooth. Eight experiments were performed on six volunteer subjects.

Quantification of jaw reflexes evoked by natural tooth contact in human subjects.

Inhibitory jaw reflexes are believed to be important for protecting the teeth and temporo-mandibular structures from damage during sudden or forceful biting or mastication. Accordingly, alterations in these reflexes are sometimes implicated in aetiologies proposed for oro-facial pain syndromes, although the association is not well-established. We now aim to develop a method for quantifying objectively inhibitory jaw reflexes evoked by natural tooth contact.

The inhibitory effect of a chewing task on a human jaw reflex.

This study was undertaken to investigate whether an inhibitory jaw reflex could be modulated by experimentally controlled conditions that mimicked symptoms of temporomandibular disorders. Reflecting on previous work, we anticipated that these conditions might suppress the reflex. Electromyographic recordings were made from a masseter muscle in 18 subjects, while electrical stimuli were applied to the upper lip.

Mastication and swallowing: 2. control.

Unlabelled: In recent years, it has become clear that the neural mechanisms controlling chewing and swallowing emanate from centres in the brainstem. However, these activities may be modulated by conscious processes and by feedback from peripheral nerves.This review relates this knowledge to clinical dentistry and, in particular, to the possible relationship between craniomandibular dysfunctions and impaired control of the masticatory system.

Mastication and swallowing: 1. Functions, performance and mechanisms.

Unlabelled: The process of mastication involves movements of the tongue, lips and cheeks as well as the more obvious actions of the teeth and jaws. In recent years there have been significant advances in our knowledge of the relationships between these movements in human beings and of how the processes of mastication are related to the associated events of swallowing. In this, the first of two papers, we review the role of mastication in food processing and nutrition and the effect of tooth loss on masticatory performance.

The effects of a maximal jaw clench on an inhibitory jaw reflex.

The purpose of this study was to determine whether mimicking symptoms of temporomandibular disorders by experimentally activating deep nociceptors in the oro-facial region, can modulate an inhibitory jaw reflex. In human subjects, electromyograms were recorded from one (eight subjects) or both (16 subjects) active masseter muscles and electrical stimuli were applied to the upper lip. This procedure was performed before and after a 30-s conditioning period in which the subjects maximally clenched the jaw.

Prospective clinical study of a new adhesive gelling foam dressing in pressure ulcers.

This prospective, non comparative study evaluated the safety and effectiveness of an adhesive gelling foam dressing in pressure ulcer management. Twenty-three subjects with exuding pressure ulcers were recruited from seven centres in the USA and Canada. Study treatment included an adhesive gelling foam dressing, optional tape/roll bandaging and mandatory pressure-reducing/relieving devices.

Differences between inhibitory jaw reflexes evoked by stimulation of tooth pulp and across the adjacent alveolar process in man.

Objective: In humans, stimulation of nerves in or around teeth can evoke inhibitory jaw reflexes. Previous studies had suggested that there may be subtle differences in the timings of the responses. The aim of the present study was to investigate this by comparing reflexes evoked by electrical stimulation of a tooth and of the adjacent tissues in individual subjects.

Modulation of an inhibitory jaw reflex by remote noxious stimulation: effects of spatial conditioning factors.

In humans, inhibitory jaw reflexes can be depressed by painful stimulation of remote parts of the body. The underlying mechanisms may involve diffuse noxious inhibitory controls (DNIC). Animal experiments have shown that the neurons which may mediate DNIC show spatial encoding (i.

Dissociation of nociceptive modulation of a human jaw reflex from the influence of stress.

In human beings, inhibitory jaw reflexes can be depressed by painful stimulation of remote parts of the body. Since similar effects can be produced by the stress of anticipating pain, we wished to investigate whether the effects of remote painful stimuli are dependent on stress. EMG recordings were made from a masseter muscle while subjects maintained activity in the muscle at approximately 12.

Characteristics of a jaw reflex in humans with temporomandibular disorders: a preliminary report.

Electromyography was used to compare characteristics of an inhibitory jaw reflex in 10 temporomandibular disorder patients and 10 age- and sex-matched healthy controls. The methodology was novel in that the reflex was that evoked in the active masseter muscle, by electrical stimulation of perioral skin. This response has advantages over those previously studied as it avoids problems associated with stimulating in the moist intra-oral environment and it is monophasic, thus permitting easy quantification.

Educating nurses about cardiac monitoring in a stroke unit.

Nurses in the 20-bed Stroke and Rehabilitation Unit at Bankstown-Lidcombe Hospital in Sydney, Australia, recently faced the significant challenge of learning how to use cardiac monitors and read and interpret cardiac rhythm strips. This article focuses on the philosophy used to drive their education process, barriers to learning, implementation, and influences on the nurses' workload. Stroke nurses can successfully learn the key elements of cardiac monitoring if provided with proper motivation, education, and support.

Functional roles of oral reflexes in chewing and biting: phase-, task- and site-dependent reflex sensitivity.

Because loading during chewing is not totally predictable and jaw-closing muscles are strong and act over short distances, feedback from oral receptors is important in the control of mastication. Information on such feedback can be obtained by studying reflexes in jaw muscle EMGs. This review will deal with the contribution of reflex mechanisms to modifying motor neuron activity during chewing, and the dependency of reflex sensitivity on motor task, phase of movement, and site of stimulation.

Modulation of human jaw reflexes: heterotopic stimuli and stress.

The inhibitory reflexes in jaw elevator muscles, which are the predominant muscle responses to stimuli in or around the human mouth, are subject to modulation by nociceptive stimulation of remote parts of the body. The evidence for, and nature of, these modulatory effects are reviewed with particular emphasis on the reflex inhibition of masseteric activity evoked by electrical stimulation of the upper lip. This reflex is markedly reduced in magnitude by noxious stimulation of remote parts of the body surface or deeper tissues.

Differentiation of nociceptive- from stress-induced modulatory influences on human reflexes.

This paper describes a new protocol that addresses the question of whether, in human experiments, modulatory effects of remote nociceptive conditioning stimuli on reflex responses are mediated by the stress induced by the conditioning stimuli. The protocol has been illustrated by a study into the effect of a remote nociceptive conditioning stimulus on an inhibitory jaw reflex. Electromyograms were recorded from an active masseter muscle and inhibitory reflexes were evoked by applying electrical stimuli to the upper lip.

A phase I study of antisense oligonucleotide GTI-2040 given by continuous intravenous infusion in patients with advanced solid tumors.

Background: This study of GTI-2040, a 20-mer phosphorothioate oligonucleotide complementary to the messenger ribonucleic acid (mRNA) of the R2 subunit of ribonucleotide reductase (RNR), was conducted to determine the dose-limiting toxicity (DLT) and maximum-tolerated dose (MTD) of the agent in patients with advanced solid tumors or lymphoma. Plasma pharmacokinetics of GTI-2040 and suppression of RNR expression in peripheral blood mononuclear cells were also studied.

Patients And Methods: GTI-2040 was administered as a continuous intravenous infusion for 21 days every 4 weeks.

Remote noxious stimuli modulate jaw reflexes evoked by activation of periodontal ligament mechanoreceptors in man.

The purpose of the study was to investigate whether jaw reflexes evoked by selective stimulation of periodontal ligament me canoreceptors are susceptible to modulation by remote noxious stimulation. Experiments were performed on 10 volunteer subjects. Skin surface recordings were made from the jaw-closing masseter muscle.

Voluntary and reflex control of the human temporalis muscle.

Electromyographic recordings (EMGs) were made in 10 human subjects from the anterior and posterior parts of the temporalis muscle using skin surface electrodes. The activities produced by voluntary maximal clenching tasks and the reflex responses to electrical stimulation of the muco-gingival junction were studied. In most subjects, maximum activity in both parts of the muscle occurred when clenching in the intercuspal position (anterior temporalis: 7 of 10 subjects; posterior temporalis: 9 of 10 subjects).

Topical review: modulation of trigeminal sensory input in humans: mechanisms and clinical implications.

In this review, the modulatory effects of tooth and implant loading, orofacial pain, and psychological factors on somatosensory and jaw-motor function in humans are assessed. Experimental studies on the control of jaw actions have revealed that patients with prostheses supported by osseointegrated implants show an impairment of fine motor control of the mandible. One possibility is that this may be related to the loss of afferent information from periodontal ligament mechanoreceptors, which results in considerably higher and more variable forces to hold and manipulate food between the teeth.

Animal models of nociception.

The study of pain in awake animals raises ethical, philosophical, and technical problems. We review the ethical standards for studying pain in animals and emphasize that there are scientific as well as moral reasons for keeping to them. Philosophically, there is the problem that pain cannot be monitored directly in animals but can only be estimated by examining their responses to nociceptive stimuli; however, such responses do not necessarily mean that there is a concomitant sensation.

The neural mechanisms of oral and facial pain.

Pain is a complex and variable phenomenon that can be influenced by many factors. The neural pathways serving pain are not passive conduits, but are part of a dynamic system which can result in different levels of pain resulting from similar injuries under different circumstances. The passage of signals in these pathways may be inhibited or enhanced at almost any level, from the peripheral sensory receptors to the higher centres of the brain.