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T L Moore

Publications and source records attributed to T L Moore.

At least 19 recordsLinked to original sources
PubMed2007

Abnormal kappa:lambda light chain ratio in circulating immune complexes as a marker for B cell activity in juvenile idiopathic arthritis.

Patients with juvenile idiopathic arthritis (JIA) have been shown to have elevated levels of circulating immune complexes (CICs) which correlated with disease activity. Our aim was to assess B cell activity by measuring the amount of and the kappa:lambda chain immunoglobulin light (L) chain ratio in CICs from JIA patients and to determine potential evidence for either an antigen-driven response or B-cell receptor editing. We used an enzyme-linked immunosorbent assay to measure kappa and lambda chains present in the CICs from the sera of patients with JIA. Statistical analysis was performed using Pearson's correlation, one-way ANOVA and Bonferroni post hoc analysis. Sera from 44 JIA patients were examined for the concentration of L chains in CICs. Healthy controls had a kappa:lambda chain ratio of 1.2:1, whereas this ratio was reversed among JIA subgroups with RF-positive polyarthritis (1:1.2), RF-negative polyarthritis (1:1.3), oligoarthritis (1:2.3) and systemic-onset arthritis (1:2.5). In addition, overall lambda chain selection was not significantly associated with a particular immunoglobulin heavy (H) chain and occurred with all immunoglobulin isotypes. We showed preferential selection of lambda chains contributing to the formation of potentially pathogenic CICs from JIA patients, of all onset types compared to healthy controls, in an H chain-independent manner. The reversal of kappa:lambda chain ratio within the JIA CICs and association with all immunoglobulin isotypes demonstrated the potential for L chain editing. Furthermore, we conclude that a reversal of the normal kappa:lambda chain ratio in JIA CICs may be used as a marker for increased B-cell activity.

Adolescent↗
PubMed2006

The 'distal-dorsal difference': a thermographic parameter by which to differentiate between primary and secondary Raynaud's phenomenon.

OBJECTIVE: To test the hypothesis that in a patient with Raynaud's phenomenon (RP), a difference of >1 degrees C between the fingertips and the dorsum of the hand ['distal-dorsal difference' (DDD), fingers cooler] is specific for underlying structural vascular disease as occurs in systemic sclerosis (SSc), and to evaluate other thermographic parameters in the separation of secondary from primary RP. METHODS: A retrospective analysis of the case notes and thermography results of patients attending thermography, primarily over a 2-yr period. Multinomial logistic regression was used to ascertain whether thermography variables differed between groups with primary RP (56 patients), undifferentiated connective tissue disease (21 patients) and SSc (45 patients), with adjustment for age, sex and smoking. RESULTS: A DDD >1 degrees C in any finger at 30 degrees C had a positive predictive value of 70%, and a negative predictive value of 82%, in identifying the patient with RP secondary to SSc. From the results of the multinomial logistic regression, a score was derived incorporating age, number of fingers with DDD >1 degrees C at 30 degrees C and maximum rewarming gradient. This score (with a suitable cut-off) was 82% sensitive and 82% specific in identifying RP secondary to SSc, with a positive predictive value of 73% and a negative predictive value of 89%. CONCLUSION: Parameters derived from thermography (incorporating both a heat and cold challenge) aid in the prediction of SSc in patients with RP.

Adult↗
PubMed2006

Abnormal microvascular response is localized to the digits in patients with systemic sclerosis.

OBJECTIVE: To investigate the hypothesis that cutaneous microvascular perfusion of the dorsum of the hand (in response to local heating) and distal phalanx (in response to occlusion) is impaired in patients with systemic sclerosis (SSc) compared with healthy controls. METHODS: Twenty-nine patients with SSc and 29 control subjects were recruited. Perfusion was monitored using novel dual-wavelength laser Doppler imaging, allowing measurement of both smaller (capillaries) and larger (thermoregulatory) vessels. Postacclimatization, a baseline dorsum scan (red or green wavelength) was performed. A heating pad was placed on the dorsum (total stimulus time 6 minutes at 34-40 degrees C), and following removal of the pad, baseline wavelength scans were performed until perfusion returned to baseline values. This was then repeated for the second wavelength. The maximum perfusion increase due to heating (PEAK1) and area under the perfusion-time curve (AUC) were determined. In addition, scans (both wavelengths) of the index finger were performed prior to and during 2 minutes of suprasystolic occlusion, and the response upon occlusion release was monitored with single-point laser Doppler. The decrease in perfusion due to occlusion (from preocclusion baseline values) (%DECREASE) and the maximum increase (from baseline perfusion values under occlusion) in hyperemic perfusion upon removal of occlusion (PEAK/OCC) were calculated. RESULTS: PEAK1 and AUC values were not significantly different between patients and controls, as assessed with either wavelength. A significant difference between groups was found in the %DECREASE values with the green, but not the red, wavelength. A significant between-group difference was also found in PEAK/OCC values, using both wavelengths. CONCLUSION: This study suggests that SSc has no effect on microvascular perfusion in the dorsum of the hand, and that the abnormal microvascular response is localized to the digits, affecting both smaller and larger vessels.

Adult↗
PubMed2006

Presence of plasma complement regulatory proteins clusterin (Apo J) and vitronectin (S40) on circulating immune complexes (CIC).

The complement regulatory (CR) proteins clusterin and vitronectin bind to the membrane attack complex (MAC) and thus prevent cytolysis. In this report, we demonstrate the presence of both of these CR proteins on MAC bound to circulating immune complexes (CIC). We measured the amount of clusterin and vitronectin on MAC in plasma, also referred to as soluble MAC (SMAC), as well as on MAC bound to CIC (MAC-CIC), using antibody directed to polymerized C9 in systemic lupus erythematosus (SLE) patients. We observed a strong correlation among the quantities of SMAC and MAC-CIC. The amount of both clusterin and vitronectin associated with MAC-CIC was two- to threefold higher in comparison to the SMAC. Patients with high levels of clusterin and vitronectin demonstrated renal involvement. We hypothesize that these complement regulatory proteins besides regulating the insertion of MAC play other critical roles, in disease pathogenesis.

Antigen-Antibody Complex↗
PubMed2005

Juvenile localized scleroderma: clinical and epidemiological features in 750 children. An international study.

OBJECTIVE: Juvenile localized scleroderma (JLS) includes a number of conditions often grouped together. With the long-term goal of developing uniform classification criteria, we studied the epidemiological, clinical and immunological features of children with JLS followed by paediatric rheumatology and dermatology centres. METHODS: A large, multicentre, multinational study was conducted by collecting information on the demographics, family history, triggering environmental factors, clinical and laboratory features, and treatment of patients with JLS. RESULTS: Seven hundred and fifty patients with JLS from 70 centres were enrolled into the study. The disease duration at diagnosis was 18 months. Linear scleroderma (LS) was the most frequent subtype (65%), followed by plaque morphea (PM) (26%), generalized morphea (GM) (7%) and deep morphea (DM) (2%). As many as 15% of patients had a mixed subtype. Ninety-one patients (12%) had a positive family history for rheumatic or autoimmune diseases; 100 (13.3%) reported environmental events as possible trigger. ANA was positive in 42.3% of the patients, with a higher prevalence in the LS-DM subtype than in the PM-GM subtype. Scl70 was detected in the sera of 3% of the patients, anticentromere antibody in 2%, anti-double-stranded DNA in 4%, anti-cardiolipin antibody in 13% and rheumatoid factor in 16%. Methotrexate was the drug most frequently used, especially during the last 5 yr. CONCLUSION: This study represents the largest collection of patients with JLS ever reported. The insidious onset of the disease, the delay in diagnosis, the recognition of mixed subtype and the better definition of the other subtypes should influence our efforts in educating trainees and practitioners and help in developing a comprehensive classification system for this syndrome.

Adolescent↗
PubMed2005

A pilot study of acetic acid iontophoresis and ultrasound in the treatment of systemic sclerosis-related calcinosis.

OBJECTIVES: Our aim was to perform a pilot study to investigate whether iontophoresis of acetic acid, followed by ultrasound, might be a safe and effective treatment for systemic sclerosis (SSc)-related calcinosis. This combination treatment has been used in other calcifying disorders. METHODS: Three female patients (ages 51, 62 and 59 yr) were studied. Each underwent treatment nine times over a 3-week period. Iontophoresis was with 2-5% acetic acid at 100 microA for 20 min, followed by ultrasound at 1.5 W/cm(2) for 8 min at each visit. The primary endpoint was the degree of radiographic calcinosis as quantified by image analysis after adjusting for soft tissue change. RESULTS: There were no side-effects from treatment. Mean radiographic intensity fell in all patients (by 18.0, 8.9 and 8.5%), although the maximum density and the area of calcinosis fell in only one patient. However, none of the patients reported any benefits from the treatment. CONCLUSIONS: In this small pilot study none of the patients experienced clinical improvement, despite an intensive treatment schedule over 3 weeks. However, there may have been some radiographic improvement. Given that there is currently no effective treatment for SSc-related calcinosis a larger study incorporating higher 'doses' of iontophoresis is indicated.

Acetic Acid↗
PubMed2005

Dual wavelength (532 and 633 nm) laser Doppler imaging of plaque psoriasis.

BACKGROUND: Increased blood flow occurs in plaques of psoriasis, and an increase in blood flow has been shown to occur in uninvolved skin adjacent to the active edge. OBJECTIVES: In order to gain more insight into the pathophysiology of the active edges of plaques of psoriasis, we investigated different components of the microcirculation in the lesional and nonlesional skin of patients with psoriasis, using dual wavelength laser Doppler imaging (LDI). METHODS: The cutaneous blood flow in 23 plaques on the forearms of 20 patients with chronic plaque psoriasis was recorded using dual wavelength LDI. Perfusion was determined within the plaque (P), in uninvolved skin adjacent to the plaque (A) and in nonadjacent skin (U). RESULTS: Perfusion in plaques was increased as imaged by either 633 nm (red wavelength) or 532 nm (green wavelength) compared with both adjacent and nonadjacent uninvolved skin: median (interquartile range) P/A(RED) = 3.7 (2.5-4.9), P/A(GREEN) = 1.3 (1.2-1.6), P/U(RED) = 4.2 (2.7-6.1), P/U(GREEN) = 1.5 (1.3-1.9). CONCLUSIONS: Vascular perfusion is increased within plaques of psoriasis compared with adjacent and nonadjacent uninvolved skin. The results suggest an area of increased perfusion in skin adjacent to plaques, when compared with nonadjacent skin, for both deeper (large) and superficial (small) vessels (imaged by 633 and 532 nm, respectively). We believe that this dual wavelength tool may be a suitable and useful way of assessing pathophysiology and treatment response in psoriasis.

Adolescent↗
PubMed2005

A role for the complement system in rheumatoid arthritis.

The production of autoreactive antibodies from self-reactive B cells results in the formation of immune complexes that deposit in tissue and fix complement, contributing to the pathogenesis of rheumatoid arthritis (RA). Earlier mouse models emphasize the importance of autoreactive antibodies formed against "self" proteins that serve as a source for T cell-mediated immune response, stemming from cross-reactivity and resulting in B cell activity. However, more recent models suggest the need for both autoantibodies and the initiation of the inflammatory cascade via the alternative complement pathway, which is unbridled as the cartilage lacks the usual regulatory proteins of the complement system. Furthermore, deficiencies in specific complement proteins could lead to an escape from negative selection by these self-reactive B cells. Moreover, the classical complement pathway establishes chemotactic gradients by which inflammatory cells follow and accumulate in the synovial fluid where they engulf immune complexes and release proteolytic enzymes. In addition, the processing of circulating immune complexes either via Fc receptor or CR1 and opsonization by complement fragments plays a key role in determining the fate of immune status. In addition, complement proteins are a major determinant in the size and solubility of an immune complex, which also affects clearance. The evidence regarding intra-articular activation of the complement system in RA provides the possibility to pharmacologically manipulate various parts of the complement system for therapeutic purposes and potential therapeutic targets for the control of inflammation and the prevention of joint destruction.

Animals↗
PubMed2004

Digital iontophoresis of vasoactive substances as measured by laser Doppler imaging--a non-invasive technique by which to measure microvascular dysfunction in Raynaud's phenomenon.

OBJECTIVE: To test the hypothesis that microvascular vasodilation is impaired in patients with systemic sclerosis (SSc) compared with patients with primary Raynaud's phenomenon (PRP) and healthy controls, using the technique of laser Doppler imaging to quantify blood flow responses to iontophoresis of vasoactive agents. METHODS: Microvascular blood flow was measured by laser Doppler imaging before, during and after 120 s iontophoresis (30 microA) of 1% acetylcholine chloride (ACh, endothelium-dependent) and 1% sodium nitroprusside (NaNP, endothelium-independent). Two adjacent fingers of the left hand were studied, and the procedure then repeated on the right. Ten patients with limited cutaneous SSc (LCSSc), 10 patients with PRP and 11 healthy control subjects were studied. RESULTS: Vasodilation in response to both ACh and NaNP iontophoresis, as measured by 'area under the blood flow.time curve' (AUC), normalized for baseline flux, was similar in the control and PRP groups, but was diminished in the LCSSc group compared with both control and PRP groups (ACh results: control vs LCSSc P = 0.028, PRP vs LCSSc P = 0.005; NaNP results: control vs LCSSc P = 0.004, PRP vs LCSSc P = 0.005). There were no differences between groups in baseline flux values nor in voltages required to drive the 30 microA current. CONCLUSIONS: Both endothelium-dependent and endothelium-independent vasodilation are impaired in patients with LCSSc. Vasodilatory responses in patients with PRP are similar to those in controls. If reproducibility is confirmed to be satisfactory, then these techniques could be used to examine disease progression over time and responsiveness to vasoactive treatment, thus facilitating clinical trials.

Acetylcholine↗
PubMed2004

Normal aging results in decreased synaptic excitation and increased synaptic inhibition of layer 2/3 pyramidal cells in the monkey prefrontal cortex.

Executive system function, mediated largely by the prefrontal cortex (PFC), often declines significantly with normal aging in humans and non-human primates. The neural substrates of this decline are unknown, but age-related changes in the structural properties of PFC neurons could lead to altered synaptic signaling and ultimately to PFC dysfunction. The present study addressed this issue using whole-cell patch clamp assessment of excitatory and inhibitory postsynaptic currents (PSCs) in layer 2/3 pyramidal cells in in vitro slices of the PFC from behaviorally characterized young (< or =12 years old) and aged (> or =19 years old) rhesus monkeys. Behaviorally, aged monkeys were significantly impaired in performance on memory and executive system function tasks. Physiologically, the frequency of spontaneous glutamate receptor-mediated excitatory PSCs was significantly reduced in cells from aged monkeys, while the frequency of spontaneous GABAA receptor-mediated inhibitory PSCs was significantly increased. In contrast, there was no effect of age on the frequency, amplitude, rise time or decay time of action potential-independent miniature excitatory and inhibitory PSCs. The observed change in excitatory-inhibitory synaptic balance likely leads to significantly altered signaling properties of layer 2/3 pyramidal cells in the PFC with age.

Aging↗
PubMed2003

Seventeen-point dermal ultrasound scoring system--a reliable measure of skin thickness in patients with systemic sclerosis.

OBJECTIVE: Our objective was to develop a 17-site ultrasound method of measuring skin thickness in patients with systemic sclerosis (SSc) and to assess its inter- and intra-observer variability. METHODS: Dermal thickness (using a 22 MHz ultrasound probe) was measured at 17 sites (corresponding to those assessed in the modified Rodnan skin score) in 39 patients with SSc (26 limited cutaneous, 13 diffuse) and 34 healthy controls. The sum of the thicknesses (at the 17 sites) and the maximal thickness were also documented. Because skin thickness varies between sites, each measurement was converted to a z-score. Inter- and intra-observer variability were assessed in 35 patients/33 controls, and 20 patients/15 controls respectively. RESULTS: Measurement precision was good for the dermal measurements-intraclass correlation coefficients at the 17 sites ranged from 0.65 to 0.94 for the inter-observer variability (0.86 for maximum thickness) and from 0.55 to 0.96 for the intra-observer variability (0.92 for maximum thickness). CONCLUSION: Our results suggest that the 17-point dermal ultrasound scoring system is extremely reliable and may therefore be a useful measure of outcome, including in clinical trials.

Adult↗
PubMed2003

Hypertension-induced changes in monoamine receptors in the prefrontal cortex of rhesus monkeys.

Hypertension affects approximately 60 million people in the United States. Recent studies have demonstrated that hypertension may produce progressive changes in the CNS. The present study is focused on reports in the literature that hypertension may significantly alter neurotransmitter systems, particularly dopamine (DA) and norepinephrine (NE). To address this, DA and norepinephrine (NE) receptor binding was assessed in the prefrontal cortex (PFC) of 15 male rhesus monkeys using on-the-slide in vitro assays for the DA1, NE alpha1 and NE alpha2 receptors as well as for the DA and NE uptake transporters. Eight monkeys underwent surgical coarctation of the mid-thoracic aorta which produced sustained, untreated hypertension as defined by a systolic pressure above 150 mm Hg. Compared with normotensive controls, chronic, untreated hypertension produced a significant decrease in DA1 and NE alpha1 receptor binding and an increase in DA uptake (DAU) receptor binding in the prefrontal cortex. While the mechanisms by which untreated hypertension alters DA and NE receptors is not known, the use of this non-human primate model should provide the means to uncover neurobiological changes that occur with untreated hypertension.

Animals↗
PubMed2002

Digital vascular response to topical glyceryl trinitrate, as measured by laser Doppler imaging, in primary Raynaud's phenomenon and systemic sclerosis.

OBJECTIVE: To investigate digital microvascular responses to topical glyceryl trinitrate (GTN) in patients with primary Raynaud's phenomenon (PRP), limited cutaneous systemic sclerosis (LCSSc) and healthy control subjects, using laser Doppler imaging. METHODS: Ten patients with PRP, 13 with LCSSc and 10 control subjects were studied. Baseline skin microvascular blood flow of the dorsum of the index, middle and ring fingers of the non-dominant hand was measured using scanning laser Doppler imaging. After the initial image, 2% GTN ointment was rubbed on the dorsum of one finger for 1 min; placebo ointment was rubbed on the dorsum of a second finger for 1 min, and the third finger remained untreated. Further laser Doppler scanning of these three fingers was conducted immediately, 10 and 20 min after ointment application. RESULTS: There was increased blood flow response to placebo compared with no treatment (P<0.001) and to GTN compared with placebo (P=0.004). The change in blood flow over time differed significantly between placebo and GTN (P<0.001), but not between placebo and no ointment application: blood flow increased with GTN and decreased with placebo/no treatment at 10 and 20 min. There were no differences in initial baseline blood flow or response between the subject groups. CONCLUSIONS: An exogenous supply of nitric oxide by topical GTN ointment causes local endothelial-independent vasodilatory responses in PRP, LCSSc patients and control subjects. As well as demonstrating the effectiveness of topical GTN in patients with PRP and LCSSc, this study illustrates the ability of laser Doppler imaging to quantify local vasodilatory effects.

Administration, Topical↗
PubMed2002

Therapeutic use of etanercept in polyarticular course juvenile idiopathic arthritis over a two year period.

OBJECTIVE: To analyse the treatment response to etanercept in patients with polyarticular course juvenile idiopathic arthritis (JIA). METHODS: 22 patients with polyarticular course JIA (19 females, three males; mean age 13.9 years; mean disease duration 6.3 years; 15 with polyarticular onset, seven with systemic onset, one with residual systemic activity; eight rheumatoid factor positive; eight with erosive disease) were treated with etanercept for up to 24 months. Etanercept was given subcutaneously at 0.4 mg/kg twice a week. Treatment response was ascertained in an open prospective study. RESULTS: All patients showed impressive clinical improvement, with a decrease in swollen joint count by an average of 10.1 joints (mean of 49% decrease), a decrease in tender joint count by 9.3 joints (mean of 94%), and decrease in total joint count by 11.2 joints (mean of 48%). Duration of morning stiffness decreased to less than 10 minutes. Furthermore, haemoglobin concentration increased on average by 14 g/l (mean of 15.3%) and packed cell volume increased by 0.035 (mean increase of 12%), and erythrocyte sedimentation rate decreased on average by 42.8 mm/1st h (mean decrease of 64%). No major side effects were noted. CONCLUSION: Etanercept continues to be clinically effective and well tolerated in patients with polyarticular course JIA over a two year period.

Adolescent↗
PubMed2001

Modeling modulus reduction in bovine trabecular bone damaged in compression.

Loading bone beyond its yield point creates microdamage, leading to reduction in stiffness. Previously, we related microdamage accumulation to changes in mechanical properties. Here, we develop a model that predicts stiffness loss based on the presence of microdamage. Modeling is done at three levels: (1) a single trabecula, (2) a cellular solid consisting of intact, damaged, and fractured trabeculae, and (3) a specimen with a localized damage band. Predictions of a reduced modulus agree well with experimental measured modulus reductions of post-yield compression of bovine trabecular bone. The predicted reduced modulus is relatively insensitive to changes in the input parameters.

Animals↗
PubMed2001

Clinical response to etanercept in polyarticular course juvenile rheumatoid arthritis.

OBJECTIVE: To evaluate safety and clinical response to treatment with etanercept in the polyarticular course of patients with juvenile rheumatoid arthritis (JRA). METHODS: Ten patients were studied (8 female, 2 male; 6 polyarticular JRA, 4 systemic onset; mean age 13.3 yrs; mean duration of disease 6.6 yrs). Patients received 0.4 mg/kg etanercept subcutaneously twice weekly in addition to their existing therapeutic regimen. Observed duration of treatment ranged between 4 and 12 months. RESULTS: Patients tolerated treatment with etanercept well. No serious adverse events were noted. Treatment response showed considerable improvement of morning stiffness (mean reduction of 96 min approximately equal to -93%) and joint counts including swollen joints (delta -8.2 approximately equal to -40%), tender joints (delta -9.2 approximately equal to -88%), and total joints (delta -9.8 approximately equal to -37%). Laboratory results included decreases in ESR (delta -46 mm/h approximately equal to -53%) and improvement of anemia. CONCLUSION: Our results confirm etanercept is a powerful adjunct in the therapy of polyarticular JRA resistant to conventional treatment regimens.

Adolescent↗