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1.
J Child Neurol ; 37(4): 303-313, 2022 03.
Article in English | MEDLINE | ID: mdl-34927485

ABSTRACT

Autoimmune encephalitis is an increasingly recognized entity in children. When treated promptly, favorable outcomes are seen in a majority of pediatric patients. However, recognition of autoimmune encephalitis in young patients is challenging. Once autoimmune encephalitis is suspected, additional difficulties exist regarding timing of treatment initiation and duration of treatment, as evidence to guide management of these patients is emerging. Here, we review available literature regarding pediatric autoimmune encephalitis and present our institution's comprehensive approach to the evaluation and management of the disease. These guidelines were developed through an iterative process involving both pediatric neurologists and rheumatologists.


Subject(s)
Encephalitis , Hashimoto Disease , Child , Cognition , Encephalitis/diagnosis , Encephalitis/therapy , Hashimoto Disease/diagnosis , Hashimoto Disease/therapy , Humans , Neurologists
2.
Rheumatology (Oxford) ; 60(10): 4495-4507, 2021 10 02.
Article in English | MEDLINE | ID: mdl-33493312

ABSTRACT

OBJECTIVES: To assess efficacy, pharmacokinetics (PK) and safety of intravenous (i.v.) golimumab in patients with polyarticular-course JIA (pc-JIA). METHODS: Children aged 2 to <18 years with active pc-JIA despite MTX therapy for ≥2 months received 80 mg/m2 golimumab at weeks 0, 4, then every 8 weeks through week 52 plus MTX weekly through week 28. The primary and major secondary endpoints were PK exposure and model-predicted steady-state area under the curve (AUCss) over an 8-week dosing interval at weeks 28 and 52, respectively. JIA ACR response and safety were also assessed. RESULTS: In total, 127 children were treated with i.v. golimumab. JIA ACR 30, 50, 70, and 90 response rates were 84%, 80%, 70% and 47%, respectively, at week 28 and were maintained through week 52. Golimumab serum concentrations and AUCss were 0.40 µg/ml and 399 µg ⋅ day/ml at week 28. PK exposure was maintained at week 52. Steady-state trough golimumab concentrations and AUCss were consistent across age categories and comparable to i.v. golimumab dosed 2 mg/kg in adults with rheumatoid arthritis. Golimumab antibodies and neutralizing antibodies were detected via a highly sensitive drug-tolerant assay in 31% (39/125) and 19% (24/125) of patients, respectively. Median trough golimumab concentration was lower in antibody-positive vs antibody-negative patients. Serious infections were reported in 6% of patients, including one death due to septic shock. CONCLUSION: Body surface area-based dosing of i.v. golimumab was well tolerated and provided adequate PK exposure for clinical efficacy in paediatric patients with active pc-JIA.ClinicalTrials.gov number NCT02277444.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antirheumatic Agents/administration & dosage , Arthritis, Juvenile/drug therapy , Arthritis/drug therapy , Administration, Intravenous , Adolescent , Child , Child, Preschool , Female , Humans , Male , Treatment Outcome
3.
Nat Commun ; 9(1): 4437, 2018 10 25.
Article in English | MEDLINE | ID: mdl-30361627

ABSTRACT

Focal electrical stimulation of the brain incites a cascade of neural activity that propagates from the stimulated region to both nearby and remote areas, offering the potential to control the activity of brain networks. Understanding how exogenous electrical signals perturb such networks in humans is key to its clinical translation. To investigate this, we applied electrical stimulation to subregions of the medial temporal lobe in 26 neurosurgical patients fitted with indwelling electrodes. Networks of low-frequency (5-13 Hz) spectral coherence predicted stimulation-evoked increases in theta (5-8 Hz) power, particularly when stimulation was applied in or adjacent to white matter. Stimulation tended to decrease power in the high-frequency broadband (HFB; 50-200 Hz) range, and these modulations were correlated with HFB-based networks in a subset of subjects. Our results demonstrate that functional connectivity is predictive of causal changes in the brain, capturing evoked activity across brain regions and frequency bands.


Subject(s)
Nerve Net/physiology , Temporal Lobe/physiology , Theta Rhythm/physiology , Electric Stimulation , Evoked Potentials/physiology , Humans , White Matter/physiology
4.
Nat Commun ; 8(1): 1704, 2017 11 22.
Article in English | MEDLINE | ID: mdl-29167419

ABSTRACT

The idea that synchronous neural activity underlies cognition has driven an extensive body of research in human and animal neuroscience. Yet, insufficient data on intracranial electrical connectivity has precluded a direct test of this hypothesis in a whole-brain setting. Through the lens of memory encoding and retrieval processes, we construct whole-brain connectivity maps of fast gamma (30-100 Hz) and slow theta (3-8 Hz) spectral neural activity, based on data from 294 neurosurgical patients fitted with indwelling electrodes. Here we report that gamma networks desynchronize and theta networks synchronize during encoding and retrieval. Furthermore, for nearly all brain regions we studied, gamma power rises as that region desynchronizes with gamma activity elsewhere in the brain, establishing gamma as a largely asynchronous phenomenon. The abundant phenomenon of theta synchrony is positively correlated with a brain region's gamma power, suggesting a predominant low-frequency mechanism for inter-regional communication.


Subject(s)
Cognition/physiology , Electroencephalography Phase Synchronization/physiology , Theta Rhythm/physiology , Animals , Brain/anatomy & histology , Brain/physiology , Connectome , Gamma Rhythm/physiology , Humans , Memory/physiology , Mental Recall/physiology
5.
BMC Endocr Disord ; 17(1): 47, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-28764794

ABSTRACT

BACKGROUND: Primary adrenal insufficiency (PAI) is a rare and severe condition requiring lifelong steroid replacement. During acute illness or stressful events, it is important to appropriately adjust glucocorticoid dose; failure to do so may lead to an adrenal crisis. The aim of the study was to explore patients PAI knowledge and understanding of the condition, steroid replacement adjustment during acute illness or stress and provided education. METHODS: Ten adult patients with PAI were purposefully recruited from two hospitals in a tertiary NHS Trust in England, UK. Data was collected using a mixed method approach utilising semi-structured audio-recorded interviews and hospital case note review. Interviews were transcribed verbatim and analysed using Burnard's content analysis framework. Information from the hospital case note review was captured using a matrix table based on pre-defined criteria. RESULTS: Four key themes emerged: 'Addison's disease and hydrocortisone replacement'; 'stress and corticosteroids'; 'patient compliance/adherence' and 'transition'. Patients reported feelings of 'going through a transition from uncertainty to adaption' following diagnosis. All participants had a good level of knowledge and understanding of required medication however application in times of need was poor. Medication adherence and prevention of a crisis relied not only on patient knowledge and application but also the support of family and health professionals. Health care professional knowledge required improvement to aid diagnosis and management of PAI. CONCLUSION: Patients with PAI did not apply existing knowledge to adjust steroid dose during acute illness or stress. Although a sample of limited size, our study identified there is a need to further explore why patients with Addison's disease do not apply existing knowledge during times of increased need. Future research should consider appropriate behaviour change interventions to promote medication adherence to reduce risk of an adrenal crisis.


Subject(s)
Addison Disease/psychology , Adrenal Insufficiency/psychology , Health Knowledge, Attitudes, Practice , Hormone Replacement Therapy/psychology , Medication Adherence/psychology , Patient Education as Topic , Addison Disease/therapy , Adrenal Insufficiency/therapy , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Young Adult
7.
Clin Exp Immunol ; 160(3): 431-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20184618

ABSTRACT

Early-life exposure to appropriate microbial flora drives expansion and development of an efficient immune system. Aberrant development results in increased likelihood of allergic disease or increased susceptibility to infection. Thus, factors affecting microbial colonization may also affect the direction of immune responses in later life. There is a need for a manipulable animal model of environmental influences on the development of microbiota and the immune system during early life. We assessed the effects of rearing under low- (farm, sow) and high-hygiene (isolator, milk formula) conditions on intestinal microbiota and immune development in neonatal piglets, because they can be removed from the mother in the first 24 h for rearing under controlled conditions and, due to placental structure, neither antibody nor antigen is transferred in utero. Microbiota in both groups was similar between 2 and 5 days. However, by 12-28 days, piglets reared on the mother had more diverse flora than siblings reared in isolators. Dendritic cells accumulated in the intestinal mucosa in both groups, but more rapidly in isolator piglets. Importantly, the minority of 2-5-day-old farm piglets whose microbiota resembled that of an older (12-28-day-old) pig also accumulated dendritic cells earlier than the other farm-reared piglets. Consistent with dendritic cell control of T cell function, the effects on T cells occurred at later time-points, and mucosal T cells from high-hygiene, isolator pigs made less interleukin (IL)-4 while systemic T cells made more IL-2. Neonatal piglets may be a valuable model for studies of the effects of interaction between microbiota and immune development on allergy.


Subject(s)
Dendritic Cells/immunology , Immunity, Mucosal/physiology , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , T-Lymphocytes/immunology , Animals , Animals, Newborn , Hypersensitivity/immunology , Interleukin-2/immunology , Interleukin-4/immunology , Swine , Time Factors
8.
Proc Nutr Soc ; 64(4): 451-7, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16313686

ABSTRACT

The mucosal immune system fulfils the primary function of defence against potential pathogens that may enter across vulnerable surface epithelia. However, a secondary function of the intestinal immune system is to discriminate between pathogen-associated and 'harmless' antigens, expressing active responses against the former and tolerance to the latter. Control of immune responses appears to be an active process, involving local generation of IgA and of regulatory and/or regulated T lymphocytes. Two important periods of maximum exposure to novel antigens occur in the young animal, immediately after birth and at weaning. In both cases the antigenic composition of the intestinal contents can shift suddenly, as a result of a novel diet and of colonisation by novel strains and species of bacteria. Changes in lifestyles of man, and husbandry of animals, have resulted in weaning becoming much more abrupt than previously in evolution, increasing the number of antigens that must be simultaneously evaluated by neonates. Thus, birth and weaning are likely to represent hazard and critical control points in the development of appropriate responses to pathogens and harmless dietary and commensal antigens. Neonates are born with relatively undeveloped mucosal immune systems. At birth this factor may prevent both expression of active immune responses and development of tolerance. However, colonisation by intestinal flora expands the mucosal immune system in antigen-specific and non-specific ways. At weaning antibody to fed proteins can be detected, indicating active immune responses to fed proteins. It is proposed that under normal conditions the ability of the mucosal immune system to mount active responses to foreign antigens develops simultaneously with the ability to control and regulate such responses. Problems arise when one or other arm of the immune system develops inappropriately, resulting in inappropriate effector responses to harmless food proteins (allergy) or inadequate responses to pathogens (disease susceptibility).


Subject(s)
Food Hypersensitivity/immunology , Immunity, Mucosal/physiology , Intestinal Mucosa , Weaning , Animals , Disease Models, Animal , Gastrointestinal Tract/immunology , Gastrointestinal Tract/microbiology , Humans , Immunity, Mucosal/immunology , Immunoglobulin A/immunology , Infant , Infant, Newborn , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , Swine , T-Lymphocytes/immunology
9.
Vet Immunol Immunopathol ; 108(1-2): 189-98, 2005 Oct 18.
Article in English | MEDLINE | ID: mdl-16102842

ABSTRACT

The mucosal immune system expresses active responses against pathogens and also tolerance against harmless food and commensal bacterial antigens. The mechanisms that determine which of these outcomes occur after recognition of antigens by T-cells are not clear. One possibility is that it is determined by the initial interaction between a dendritic and a naïve T-cell in organised lymphoid tissue. However, such organised structures are, evolutionarily, quite recent and the original immune system must have made appropriate responses in more diffuse immunological architecture; a second possibility is that the critical interaction is between primed T-cells and their environment, in the lamina propria of the intestine. The mucosal immune system of neonates is poorly developed and inefficient at expressing appropriate immune responses. Development is influenced by a range of environmental factors including maternally derived antigen or antibody and commensal flora and pathogens. The intestine is a complex immunological structure in which the immune system and the macro- and microenvironment interact.


Subject(s)
Immune System/growth & development , Immunity, Mucosal , Animals , Animals, Newborn , Antigen Presentation , Dendritic Cells/immunology , Environment , Female , Immune Tolerance , Immunity, Maternally-Acquired , Lymphoid Tissue/growth & development , Lymphoid Tissue/immunology , Models, Immunological , Pregnancy , Swine , T-Lymphocytes/immunology
10.
J Immunol Methods ; 302(1-2): 156-67, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15992812

ABSTRACT

Developments in immunohistology allow the routine simultaneous use on tissue sections of three monoclonal antibodies, tagged with different fluorochromes. Such staining can identify seven different cell populations and the limiting factor is rapid, reliable and reproducible analysis. Future reliance on computer-assisted analysis of digitised images depends on validation against manual counting, often viewed as the 'gold standard'. In this study images were digitised from sections of normal porcine skin, inflamed skin and tonsil, simultaneously stained with three monoclonal antibodies. Combinations of staining were quantified by four manual counts and by pixel-based area measurement. On individual images, the correlation between automated and manual measurements was poor. Despite this, the concordance between manual and automated measurements in the means and variances of tissues was good, and both techniques identified the same changes in inflamed versus normal tissues. In addition, pixel-based counting permitted statistical analysis of co-localisation of cell types in tissue sections. We conclude that automated counting is acceptable for the assessment of tissues, is faster and provides less opportunity for observer variation than manual counting. We also demonstrate that the technique is applicable where more than three fluorochromes are used such that manual counting becomes essentially impossible.


Subject(s)
Fluorescent Antibody Technique/methods , Image Processing, Computer-Assisted/methods , Animals , Computer Simulation , Fluorescein-5-isothiocyanate , Fluorescent Antibody Technique/instrumentation , Fluorescent Antibody Technique/statistics & numerical data , Image Processing, Computer-Assisted/instrumentation , Image Processing, Computer-Assisted/statistics & numerical data , Inflammation/pathology , Jejunum/anatomy & histology , Models, Biological , Monte Carlo Method , Skin/pathology , Swine , Swine, Miniature , Xanthenes
12.
Brain Res ; 867(1-2): 223-31, 2000 Jun 09.
Article in English | MEDLINE | ID: mdl-10837817

ABSTRACT

A parallel electrophysiological and electron microscopic study was used to assess the ionic permeability of the sciatic nerve perineurium of the opossum Monodelphis domestica. The electrophysiological method was used to monitor permeability to K(+), followed by combined electron microscopy and X-ray probe analysis to monitor permeability to the electron-dense tracer lanthanum. Isolated but intact nerves were mounted in a 'grease gap' chamber for extracellular measurement of DC potential and compound action potential (CAP). Challenge with 100 mM [K(+)] Ringer was used to assess the K(+) permeability of the perineurium, since a change in DC potential (DeltaDC) under these conditions reflected changes in the axonal resting membrane potential. There was no detectable change in DC potential or CAP to the first K(+) challenge (n=71 nerves) indicating negligible K(+) permeability under control conditions. The inflammatory mediators histamine 0.1-40 mg/ml (1. 3-130 mM), bradykinin (0.1-4.7 mM) and 5HT (serotonin) 0.1-5.0 mg/ml (0.5-23.5 mM) caused no measurable DeltaDC on subsequent challenge with 100 mM [K(+)] Ringer, indicating no effect on perineurial K(+) permeability. In nerves exposed to the bile salt sodium deoxycholate (DOC, 6 min, 4 mM), challenge with elevated K(+) Ringer caused a dose-dependent DeltaDC in the range 10-100 mM [K(+)] (1.67+/-0.17 mV in 100 mM [K(+)], n=20), indicating increased perineurial permeability caused by DOC, but the response was smaller than that previously reported for the frog perineurium. Lanthanum was observed in the outer layers of the perineurium, but was not seen to penetrate the endoneurium in any of the nerves examined (n=51), even after DOC application. This study shows that the combined electrophysiological and electron microscopic technique for monitoring ionic permeability can be applied to mammalian nerve, and suggests that the opossum perineurium is more resistant to tight junction opening by chemical modulators than is the frog perineurium.


Subject(s)
Peripheral Nerves/blood supply , Peripheral Nerves/metabolism , Sciatic Nerve/blood supply , Sciatic Nerve/physiology , Animals , Anura , Biological Transport/drug effects , Biological Transport/physiology , Bradykinin/pharmacology , Deoxycholic Acid/pharmacology , Detergents/pharmacology , Electrophysiology , Female , Free Radical Scavengers/pharmacology , Histamine/pharmacology , Isotonic Solutions/pharmacology , Lanthanum/pharmacokinetics , Male , Microscopy, Electron , Neuritis/chemically induced , Neuritis/metabolism , Opossums , Peripheral Nerves/ultrastructure , Potassium/pharmacokinetics , Ringer's Solution , Sciatic Nerve/immunology , Serotonin/pharmacology
13.
Int J Sport Nutr Exerc Metab ; 10(2): 114-27, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10861333

ABSTRACT

To test the effect of diet on the short-term lipid response to exercise, fourteen moderately trained (VO2max: 50.2 +/- 6.7 ml/kg/min), healthy men (mean age: 28 +/- 4 years) were alternately fed a high fat (60 +/- 6.7% fat) and a high carbohydrate (63 +/- 3.2% carbohydrate) isoenergetic diet for 2 weeks in a randomized crossover design. During the last 4 days of the treatments, fasting total cholesterol, triglyceride, HDL-cholesterol, and HDL3-cholesterol were measured the day before, and again immediately, 24 hr, and 48 hr after exercise (4190 kJ, 70% VO2max). LDL-cholesterol and HDL2-cholesterol were calculated. Lipid concentrations were adjusted for plasma volume changes after exercise. A 2 (diet) x 4 (time) ANOVA with repeated measures revealed no significant interaction between the diet and exercise treatments. Furthermore, diet alone did not influence lipid concentrations in these trained men. Exercise resulted in an increase in HDL-C (10.7%) and HDL3-C (8.5%) concentrations and a concomitant fall in triglyceride (-25%) and total cholesterol (-3.5%). Thus, we conclude that diet composition does not affect the short-term changes in blood lipids and lipoproteins that accompany a single session of aerobic exercise in moderately trained men.


Subject(s)
Cholesterol/blood , Dietary Carbohydrates/metabolism , Dietary Fats/metabolism , Exercise/physiology , Adult , Analysis of Variance , Cross-Over Studies , Energy Intake , Humans , Male , Triglycerides/blood
14.
J Neurocytol ; 29(8): 551-67, 2000 Aug.
Article in English | MEDLINE | ID: mdl-11283412

ABSTRACT

The isolated sciatic nerve of the frog Rana temporaria was used for a parallel electrophysiological and electron microscopic examination of the ionic permeability of the perineurium, one component of the blood-nerve barrier. Nerves mounted in a grease-gap chamber for electrophysiological recording showed negligible changes in DC potential (Delta DC) or compound action potential on challenge with 100 mM K(+) Ringer, evidence that the perineurium was tight to K(+). In preparations then fixed and exposed to 5 mM lanthanum in the fixative, and examined in the electron microscope, electron-dense lanthanum deposits were seen between perineurial lamellae, but lanthanum was not detectable within the endoneurium, confirming that the perineurium was also tight to lanthanum. Absence of lanthanum penetration was confirmed by X-ray analysis of electron microscopic sections. In nerves exposed to 2 mM sodium deoxycholate (DOC) in the recording chamber, then challenged with high [K(+)], a moderate increase in perineurial K(+) permeability (P(K)) was observed, but lanthanum was still excluded. Exposure of nerves to 4 mM DOC caused a greater increase in perineurial potassium permeability, and the two nerves with the greatest permeability (P(K) > 1 x 10(-5) cm x sec(-1)) also showed detectable lanthanum within the endoneurium. The results indicate that DOC causes a dose-dependent increase in tight junctional permeability in the perineurium, and that the electrophysiological monitoring of K(+) penetration is a more sensitive measure of small ion permeability than electron microscopical analysis using lanthanum as tracer. Vesicular profiles observed in perineurial lamellae did not form open channels for ion flux across the perineurium in control nerves, or in those exposed to DOC. In preparations where lanthanum reached the endoneurium, lanthanum was observed in dense deposits in the extracellular spaces around nodes of Ranvier, and in the outer mesaxon cleft, but did not penetrate the internodal periaxonal space, the myelin intraperiod line, or the Schmidt-Lanterman incisures, in contrast to observations in mammalian nerves. The apparent differences in accessibility of the internodal periaxonal space in frog and mammalian axons are discussed in relation to axonal physiology. The study illustrates the value of parallel electrophysiological and electron microscopic examination in elucidating the properties of extracellular ionic pathways and their role in neural function.


Subject(s)
Cell Membrane Permeability/physiology , Lanthanum/pharmacokinetics , Peripheral Nerves/physiology , Potassium/metabolism , Sciatic Nerve/physiology , Tight Junctions/physiology , Animals , Deoxycholic Acid/pharmacology , Electrophysiology/methods , In Vitro Techniques , Membrane Potentials/physiology , Microscopy, Electron/methods , Peripheral Nerves/ultrastructure , Rana temporaria , Sciatic Nerve/ultrastructure , Tight Junctions/ultrastructure
15.
J Appl Physiol (1985) ; 87(1): 189-95, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10409574

ABSTRACT

Our purpose was to determine the effects of a mechanical loading intervention on mass, geometry, and strength of rat cortical bone during a period of disuse concurrent with calcium deficiency (CD). Adult female rats were assigned to unilateral hindlimb immobilization, immobilized-loaded, or control (standard chow, 1.85% calcium) treatments. Both immobilized groups were fed a CD rat chow (0.01% calcium) to induce high bone turnover. Three times weekly, immobilized-loaded rats were subjected to 36 cycles of 4-point bending of the immobilized lower leg. After 6 wk, the immobilized rats exhibited decreased tibial shaft bone mineral density (-12%), ultimate load (-19%), and stiffness (-20%; tested in 3-point bending to failure) vs. control rats. Loading prevented this decline in bone density and attenuated decreases in ultimate load and stiffness. Elastic modulus was unaffected by disuse or loading. Bone cross-sectional area in the immobilized-loaded rats was equivalent to that of control animals, even though endocortical resorption continued unabated. On the medial periosteum, percent mineralizing surface doubled vs. that in immobilized rats. This loading regimen stimulated periosteal mineralization and maintained bone mineral density, thereby attenuating the loss in bone strength incurred with disuse and concurrent calcium deficiency.


Subject(s)
Calcium/deficiency , Immobilization/adverse effects , Osteoporosis/etiology , Osteoporosis/prevention & control , Animals , Biomechanical Phenomena , Bone Density , Calcium, Dietary/administration & dosage , Disease Models, Animal , Female , Hindlimb , Rats , Rats, Sprague-Dawley , Stress, Mechanical , Tibia/pathology , Tibia/physiopathology
16.
Clin Rehabil ; 13 Suppl 1: 25-31, 1999.
Article in English | MEDLINE | ID: mdl-10685620

ABSTRACT

As in other areas of rehabilitation, relatively small numbers and diversity--both of condition and of patients' goals--hinder the assimilation of robust evidence for the effectiveness of rehabilitation. Patients with spinal cord injury (SCI) tend to be gathered together in a small number of regional services, each with their own philosophy and each with different attitudes to outcome measurement, and thus collection of the existing trials for meta-analysis is problematic. The marked improvement in outcome from SCI that has occurred with the development of specialist rehabilitation programmes argues strongly for the effectiveness of rehabilitation, and we have progressed beyond the point where randomized controlled trials that deny a group such intervention could be considered ethical. Current research is aimed at teasing apart the aspects of different care models that are most effective, or the evidence for the usefulness of interventions for control of symptoms such as spasticity and pain. This evidence is reviewed and discussed.


Subject(s)
Spinal Cord Injuries/rehabilitation , Humans , Treatment Outcome
17.
Prof Nurse ; 13(8): 515-20, 1998 May.
Article in English | MEDLINE | ID: mdl-9653293

ABSTRACT

As increasing numbers of patients are now being nursed in the community it is important that strategies for the prevention of pressures sores are in place. A prevalence survey in one trust helped staff to assess their resource needs and plan care.


Subject(s)
Pressure Ulcer/epidemiology , Beds , England/epidemiology , Humans , Nursing Audit , Pressure Ulcer/nursing , Prevalence , Risk Factors , Surveys and Questionnaires
18.
Spinal Cord ; 34(12): 736-41, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8961432

ABSTRACT

Bone is lost following spinal cord injury (SCI) and in the long-term may become osteopenic and liable to fracture. Two non-invasive techniques, ultrasound bone densitometry (USBD) and dual energy X-ray absorptiometry (DXA), have been applied to monitor bone changes after spinal injury. 31 SCI patients were scanned using an ultrasound bone densitometer, to give measurements of speed of sound (SOS), broadband ultrasound attenuation (BUA) and "stiffness'. The time since injury of these patients ranged between 5 weeks to 36 years with a mean of 5.87 +/- 10.21 years. Ultrasonic properties at the calcaneus of these patients were significantly lower than the healthy reference population, and a rapid decline in ultrasound properties occurred in the first 3 months. The fall continued up to 54 months but at a slower rate. The normal linear relationship between SOS and BUA was not altered by SCI. Eighteen patients had DXA measurements at the lumbar spine and the right proximal femur. Bone mineral density (BMD) at the femoral neck was significantly lower than the normal reference population (P < 0.05). SOS and "stiffness' correlated significantly with BMD at the lumbar spine, Ward's triangle, the femoral neck, the greater trochanter and the intertrochanteric site (P < 0.05). BUA correlated significantly at all these sites with the exception of the trochanter. A negative correlation was found between the ultrasonic properties at the calcaneus and BMD at the lumbar spine which is in contrast to the positive relationship in normal subjects. There was a tendency for BMD to increase at the lumbar spine after the first 12 months after injury, although this trend was not significant overall. The "stiffness' at the calcaneus and BMD at the femoral neck were lower than the reference population following 12 months since injury. These results show that bone deficit at the calcaneus occurs rapidly and to a severe degree after SCI, and that ultrasound has an important role to play in the assessment of bone status in these patients.


Subject(s)
Bone Density , Bone and Bones/diagnostic imaging , Spinal Cord Injuries/diagnostic imaging , Absorptiometry, Photon , Adolescent , Adult , Aged , Calcaneus/diagnostic imaging , Cross-Sectional Studies , Densitometry , Female , Humans , Male , Middle Aged , Reference Values , Ultrasonography
19.
J Appl Physiol (1985) ; 80(5): 1660-5, 1996 May.
Article in English | MEDLINE | ID: mdl-8727552

ABSTRACT

The study's objective was to determine whether estradiol (E2) deficiency alters the functional relationship of muscle to bone and causes a differential increase in injury susceptibility. Ovariectomized 6-wk-old mice were administered E2 (40 micrograms. day-1. kg-1; n = 8) or the oil vehicle (n = 8) for 21 days. The anterior crural muscles of the left hindlimb were then stimulated to produce 150 maximal in vivo eccentric contractions. In vitro functional measurements were then made on the extensor digitorum longus (EDL) muscle and tibia from both the exercised and unexercised legs. The maximal isometric torque produced by the anterior crural muscles before the eccentric contraction protocol and the unexercised EDL maximal isometric tetanic force (P(0)) were higher in E2-treated mice by 18 and 14%, respectively (P < or = 0.03). Both ultimate load and stiffness for the unexercised tibia were higher by 16% in E2-treated mice (P < or = 0.03). The muscle-to-bone relationship of these measurements was unaffected by E2 status (P > or = 0.59). No evidence for increased injury susceptibility was found in either tissue from E2-deficient mice. In fact, the decrement in P(0) was only 36.9 +/- 3.8% in exercised EDL muscles from E2-deficient mice compared with 50.6 +/- 4.2% in exercised muscles from E2-treated mice (P = 0.03). Tibia stiffness was 3.9% higher in bones from exercised legs than in bones from unexercised legs (72.64 +/- 2.77 vs. 69.95 +/- 2.66 N/mm; P = 0.05) with ultimate load showing a similar trend (P = 0.07); no effect of E2 status was observed on these differences (P > or = 0.53). In conclusion, the functional relationship of bone to muscle and the susceptibility to injury in bone are not altered by the presence of E2 in ovariectomized mice; however, E2 does increase injury susceptibility in the EDL muscle.


Subject(s)
Estradiol/pharmacology , Muscle Contraction/drug effects , Tibia/drug effects , Animals , Female , L-Lactate Dehydrogenase/metabolism , Mice , Mice, Inbred ICR , Ovariectomy
20.
Exp Cell Res ; 217(2): 554-8, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7698257

ABSTRACT

Ligand-induced translocation of epidermal growth factor receptors (EGF-R) to the nucleus of NR6/HER fibroblasts has been studied by immunoelectron microscopy. Following treatment of NR6/HER cells with epidermal growth factor (EGF) for 1 h, there was a decrease in EGF-R labeling at the plasma membrane and a corresponding increase in EGF-R in the nucleus. This was preceded by a rapid and sustained increase in nuclear phosphotyrosine content, detectable within 2 min of EGF treatment. EGF-R translocation into the nucleus was completely prevented by 18 h serum starvation prior to treatment with EGF. These results indicate that translocation of EGF-R to the nucleus is a controlled process and they suggest that EGF-R may directly influence nuclear function.


Subject(s)
Blood , Cell Nucleus/metabolism , Epidermal Growth Factor/metabolism , ErbB Receptors/metabolism , Animals , Biological Transport , Cell Line , Cell Line, Transformed , Cell Nucleus/ultrastructure , Fibroblasts , Humans , Ligands , Mice , Transfection
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