Background
Paediatric localized scleroderma is a severe inflammatory disorder associated with tissue atrophy, often leading to disability. Assessing disease activity and response to treatment has ...always been challenging and remains an important difficulty in clinical practice.
Objectives
To investigate prospectively the efficacy of systemic treatment with corticosteroids and methotrexate in children with localized scleroderma and the validity of infrared thermography, laser Doppler flowmetry and high‐frequency ultrasound in assessing disease activity.
Methods
Children with localized scleroderma were prospectively treated with corticosteroids (initially pulsed IV methylprednisolone 30 mg/kg/day, maximum 500 mg/day and/or oral prednisolone 0.5–1 mg/kg/day) and methotrexate (15 mg/m2 weekly). Treatment response was evaluated using a clinical activity score. Skin temperature, blood flow, dermal thickness and dermal echogenicity of clinically active skin lesions were determined in relation to the unaffected contralateral site at baseline and after 3, 6, 12 and 18 months. Patient charts were later reviewed for long‐term follow‐up.
Results
Twenty‐two patients were included age 6.0 (0.2–14.4 years; female‐to‐male ratio 3.4 : 1) All responded well to therapy. Disease reversibility was demonstrated in the majority of children with partial resolution of skin sclerosis and regrowth of hair. Laser Doppler flowmetry and high‐frequency ultrasound findings correlated with disease activity at baseline. Thermography had no added value in this cohort. The recurrence rate was 36% in the follow‐up period.
Conclusions
Corticosteroids and methotrexate are highly effective as first‐line therapy in paediatric localized scleroderma, leading to partial reversal of skin manifestations. However, the recurrence rate is substantial and affected children require long‐term follow‐up. Laser Doppler flowmetry and high‐frequency ultrasound correlate with disease activity in the acute phase and may assist decision‐making in these patients.
Objective. The aim of this study was to define the clinical utility of infrared thermography in disease activity detection in localized scleroderma (LS). Methods. We retrospectively reviewed 130 ...thermal images of 40 children with LS and calculated the sensitivity and specificity of thermography, comparing clinical descriptions of the lesions and contemporary thermographs. The reproducibility of thermography was calculated by using the weighted kappa coefficient to determine the level of agreement between two clinicians who reviewed the thermographs independently. Results. The sensitivity of thermography was 92% and specificity was 68%. Full concordance between the two clinicians was observed in 91% of lesions, with a kappa score of 0.82, implying very high reproducibility of this technique. Conclusion. Our results demonstrate that thermography is a promising diagnostic tool when associated with clinical examination in discriminating disease activity, as long as it is applied to lesions without severe atrophy of the skin and subcutaneous fat. Further evaluation is needed to determine whether thermography can predict the future progression of lesions.
In this paper, we report the synthesis of Fe containing strontium stannate (SrSnO
3
) nanoparticles by a facile cost-effective wet chemistry route using cetyltrimethyl ammonium bromide (CTAB) as a ...surfactant. Thermogravimetric analysis together with differential scanning calorimetric data revealed the formation of SrSn(OH)
6
as the initial compound, which led to the formation of SrSnO
3
via
three main endothermic dehydration cycles. The X-ray diffraction patterns of the final compound revealed the formation of the orthorhombic phase of SrSnO
3
with
Pbnm
symmetry, and exhibited the contraction of cell volume with increase in Fe content. Raman spectra showed peaks at 220, 256, 306, 404, 452 and 561 cm
−1
, which corresponds to Sn-O and O-Sn-O band stretching. The band gap values were found to be 4.17, 3.81 and 3.52 eV for the samples with 0, 2 and 4 at% Fe content, respectively. The photoluminescence spectra also confirmed the red shift of band emission peak observed around 370 nm. The relative permittivity was observed to be low and showed steady variation with temperature and Fe content. The dielectric relaxation time was found to decrease with temperature and increase with Fe content. The ac conductivity values were 3.23 × 10
−8
, 3.98 × 10
−8
and 4.47 × 10
−8
Ω
−1
cm
−1
, and activation energy was found to be 0.22, 0.34 and 0.44 eV for pristine and Fe (2 and 4 at%). Conductivity analysis suggested the hopping of charge carriers in the crystal, as the possible mechanism for electric conduction.
Correlation between the structural, optical and dielectric behavior of Fe doped perovskite strontium stannate nanoparticles synthesized by a facile wet chemistry route.
Chrysin is a natural, biologically active compound extracted from many plants, honey, and propolis. It possesses potent anti-inflammation, anti-cancer, and anti-oxidation properties. The mechanism by ...which chrysin initiates apoptosis remains poorly understood. In the present report, we investigated the effect of chrysin on the apoptotic pathway in U937 human promonocytic cells. We show that chrysin induces apoptosis in association with the activation of caspase 3 and that Akt signal pathway plays a crucial role in chrysin-induced apoptosis in U937 cells. Furthermore, we have shown that inhibition of Akt phosphorylation in U937 cells by the specific PI3K inhibitor, LY294002 significantly, enhanced apoptosis. Overexpression of a constitutively active Akt (myr-Akt) in U937 cells inhibited the induction of apoptosis, activation of caspase 3, and PLC-γ1 cleavage by chrysin. Together, these findings suggest that the Akt pathway plays a major role in regulating the apoptotic response of human leukemia cells to chrysin and raise the possibility that combined interruption of chrysin and PI3K/Akt-related pathways may represent a novel therapeutic strategy in hematological malignancies.
Starting with the indirect exchange model influenced by the Rashba and the Dresselhaus spin-orbit interactions, we derive the Dzyaloshinskii-Moriya interaction of localized spins. The strength of the ...Dzyaloshinskii-Moriya interaction is compared with that of the Heisenberg exchange term as a function of atomic distance. Using the calculated interaction strengths, we discuss the formation of various atomic ground states as a function of temperature and external magnetic field. By plotting the magnetic field-temperature phase diagram, we present approximate phase boundaries between the spiral, Skyrmion and ferromagnetic states of the two-dimensional weak ferromagnetic system.
In this work, a new configuration of magnetorheological brakes (MRBs) is developed in order to improve the compactness, manufacturing accuracy and cost of conventional ones. In the conventional ...configuration of MRBs, the coil is normally wound on a nonmagnetic bobbin which is placed on the stationary housing. This causes difficulties in manufacturing and the bottle-neck problem of the magnetic circuit of the MRBs. In the proposed configuration, the nonmagnetic bobbin is eliminated and the coil is wound directly on a magnetic bobbin which is a part of the housing. In this case, the magnetic bobbin part should be designed with a contractive cross-section in order to prevent magnetic flux going through and thus forcing the magnetic flux across the MR fluid (MRF) duct. After proposing the new configurations of MRBs, the modelling of the MRBs is performed based on the Bingham rheological model of the MRF. An optimal design of the proposed MRBs and conventional MRBs is then performed based on finite element analysis of the magnetic circuit of the MRBs. A comparative work between the optimal parameters of the proposed MRBs and the conventional MRBs is conducted and the advanced performance characteristics of the proposed MRBs are then investigated. In addition, experiments on both the conventional and the proposed MRBs are performed to validate the advanced performance characteristics of the proposed MRBs.
Antenatal hydronephrosis (ANH) is one of the most common anomalies identified on prenatal ultrasound, found in up to 4.5% of all pregnancies. Children with ANH are surveilled with repeated renal ...ultrasound and when there is high suspicion for a ureteropelvic junction obstruction on renal ultrasound, a mercaptuacetyltriglycerine (MAG3) Lasix renal scan is performed to evaluate for obstruction. However, the challenging interpretation of MAG3 renal scans places patients at risk of misdiagnosis.
Our objective was to analyze MAG3 renal scans using machine learning to predict renal complications. We hypothesized that our deep learning model would extract features from MAG3 renal scans that can predict renal complications in children with ANH.
We performed a case-control study of MAG3 studies drawn from a population of children with ANH concerning for ureteropelvic junction obstruction evaluated at our institution from January 2009 until June of 2021. The outcome was renal complications that occur ≥6 months after an equivocal MAG-3 renal scan. We created two machine learning models: a deep learning model using the radiotracer concentration versus time data from the kidney of interest and a random forest model created using clinical data. The performance of the models was assessed using measures of diagnostic accuracy.
We identified 152 eligible patients with available images of which 62 were cases and 90 were controls. The deep learning model predicted future renal complications with an overall accuracy of 73% (95% confidence inteveral CI 68–76%) and an AUC of 0.78 (95% CI 0.7, 0.84). The random forest model had an accuracy of 62% (95% CI 60–66%) and an AUC of 0.67 (95% CI. 0 64, 0.72)
Our deep learning model predicted patients at high risk of developing renal complications following an equivocal renal scan and discriminate those at low risk with moderately high accuracy (73%). The deep learning model outperformed the clinical model built from clinical features classically used by urologists for surgical decision making.
Our models have the potential to influence clinical decision making by providing supplemental analytical data from MAG3 scans that would not otherwise be available to urologists. Future multi-institutional retrospective and prospective trials are needed to validate our model. Display omitted
Creep and creep-rupture of Alloy 617 Wright, J.K.; Lillo, T.M.; Wright, R.N. ...
Nuclear engineering and design,
04/2018, Letnik:
329
Journal Article
Recenzirano
Odprti dostop
The Ni-Cr-Mo-Co material Alloy 617 is the leading candidate for VHTR intermediate heat exchangers operating above 750°C. Time-dependent properties are an important consideration in qualifying the ...alloy for construction of nuclear components. Creep behavior of several different heats of Alloy 617 has been evaluated in the temperature range of 800–1000°C. Power law creep behavior was observed for the minimum creep rate, with a stress exponent of 5.6 and activation energy of approximately 400kcal/Mol. The Monkman-Grant approach relating minimum creep rate to time to rupture gave a reasonable representation of the data for all of the testing with a slope of −0.84. Similarly, a modified Monkman-Grant fit the strain to failure data reasonably well. A Larson-Miller analysis was carried out to compare rupture behavior determined in the current experiments and historical data with well-known provenance over a wide range of conditions. It appears that the properties of modern heats of material are near the lower bound of rupture behavior when all of the data are considered in the same analysis.
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