Background: In the last decade the association between congenital single functional kidney (cSFK) and increased risk of hypertension, proteinuria and kidney injury has become clear. Regarding CKD long-term outcome, kidney hypertrophy at ultrasound (US) in the early months of life is reported as protective. Kidney US measuring renal lenght (BPL) and renal scintigraphy (RS) measuring GFR (mGFR) are both useful tools for the clinical management. The follow-up is frequently based on local protocols, although clinical recommendations have been proposed recently. The aim of the present study was to assess the utility of RS and to compare it to US in gathering information on kidney function, long term outcome and the appropriate use in the follow-up of patients with cSFK. Methods: Retrospective, monocentric, observational study enrolling pediatric cSKF patients. Demographic, clinical, instrumental and laboratory data were collected from medical records for all the patients included in this study. CKD was considered as composite outcome (at least one: reduced mGFR or eGFR, proteinuria in at least two different examinations, hypertension). Results: 163 cSFK patients were included. The BPL showed a linear increase over time, with curve flattening after 144 months of age. Conversely, mGFR rapidly increased between 0 and 60 months, stabilizing thereafter (Fig.1) and reaching a median value over the threshold of normal function between 24 and 60 months; we observed a slight decrease after 180 months, although not statistically significant. Comparing the trend of BPL and mGFR over time, we observed a significant correlation (R2=0.5, p-value<0.05) between 1 and 60 months of life, that was lot thereafter. Proteinuria, hypertension, impaired eGFR and mGFR were found in 11.7 %, 18.7%, 30.4% and 39.3% patients, respectively, with overall CKD rate of 41.6%. Of note, 25% of these patients were identified only by RS, having no other considered abnormality. Moreover in this subgroup patients only one showed kidney hypertrophy at US before the age of 60 months. Conclusions: RS can be as useful as US in the follow-up of cSFK. It allows to early spot an higher number of CKD patients and probably represent the best option for those with late referral in which early US is not available, to guide the clinicians in defining the risk of CKD and inform prognosis.
Laser beam machining of various materials has found wide applications in the industry due to its advantages of high-speed machining, no tool wear and no vibration, precision and accuracy, low cost of machining, etc. Investigations into the laser beam machining of uncommon alloy are still limited and more research is needed in this field. In this paper, an analysis of the laser beam machining of tungsten alloy was performed, for cutting and drilling machining processes. First, an experimental analysis of microhardness and microstructure on the laser-cut samples was performed, and then the numerical simulation of the laser beam drilling process and its experimental validation was carried out. The experiments were carried out on a tungsten alloy plate of two different thicknesses, 0.5 and 1 mm. No significant changes in the microhardness, nor in the microstructure characteristics in the heat-affected zone (HAZ), were observed for the cutting conditions considered. A two-dimensional axisymmetric mathematical model for the simulation of the laser beam drilling process is solved by a finite volume method. The model was validated by comparing numerical and experimental results in terms of the size of HAZ and the size and shape of the drilled hole. Experimental and numerical results showed that HAZ is larger in the 0.5-mm-thick plate than in the 1-mm-thick plate under the same drilling conditions. Good agreement was observed between the experimental and numerical results. The developed model improves the understanding of the physical phenomena of laser beam machining and allows the optimization of laser and process parameters.
Background: Our recent study has shown that pomegranate peel extract (PEx) showed significant immunomodulatory activity, which might be caused by ellagitannins. The aim of this work was to test the hypothesis that ellagitannin components act synergistically in the modulation of cytokine production. Methods: Human peripheral blood mononuclear cells (PBMCs) from healthy donors were stimulated with phytohemagglutinin and treated with different concentrations of PEx or punicalagin (PG), punicalin (PN), and ellagic acid (EA), alone or with their combinations. Cytotoxicity, cell proliferation, and cytokine production were determined. Results: Non-cytotoxic concentrations of all compounds significantly inhibited cell proliferation. IC50 values (μg/mL) were: EA (7.56), PG (38.52), PEx (49.05), and PN (69.95). PEx and all ellagitannins inhibited the levels of TNF-α, IL-6, and IL-8, dose-dependently, and their combinations acted synergistically. PEx and all ellagitannins inhibited Th1 and Th17 responses, whereas the lower concentrations of PEx stimulated the production of IL-10, a Treg cytokine, as did lower concentrations of EA. However, neither component of ellagitannins increased Th2 response, as was observed with PEx. Conclusions: The combination of PG, PN, and EA potentiated the anti-inflammatory response without any significant synergistic down-modulatory effect on T-cell cytokines. The increased production of IL-10 observed with PEx could be attributable to EA, but the examined ellagitannins are not associated with the stimulatory effect of PEx on Th2 response.
Voltage–current characteristics of free burning arcs in SF6 and air have been known for decades. As the demand for an SF6-free solution is increasing, there is an accompanying need to determine arc parameters in the alternative gases. An unblown arc experiment has been established to determine the voltage–current characteristics of SF6 alternative gases, which have not yet been thoroughly studied. In this experiment, free burning arc measurements were performed in a number of gases under consideration of SF6 alternatives, including CO2 and mixtures of CO2/O2 with and without C4F7N or C5F10O additives at the concentrations of up to 10 %. Measurements were also performed in air and SF6 for comparison. Arc voltage was measured in each gas at pressures ranging from 1- to 5-bar absolute, and electrode separations ranging from 20 to $95 \mathrm {~mm}$ . Voltage–current characteristic measurements for air and SF6 show good agreement with previously published results. A linear relationship of the arc voltage to the arc length is shown as well as the fourth root dependence of the arc voltage on the gas pressure. It was shown that neither the O2 nor the fluorinated additives to CO2 have any significant influence on the voltage–current characteristic. The minimum arc voltage in all measured gases was slightly higher than in SF6, but the arc in SF6 was the least stable and had the highest elongations resulting in high-voltage peaks. The arc voltage in air had a similar minimum value to the CO2-based gases, but the arc was much more stable, resulting in lower effective voltage, especially at low currents.
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