Corrigendum: A modified formula using energy system contributions to calculate pure maximal rate of lactate accumulation during a maximal sprint cycling test.

[This corrects the article DOI: 10.3389/fphys.2023.1147321.].

A modified formula using energy system contributions to calculate pure maximal rate of lactate accumulation during a maximal sprint cycling test.

Purpose: This study aimed at comparing previous calculating formulas of maximal lactate accumulation rate ( ν La.max) and a modified formula of pure ν La.max (P ν La.max) during a 15-s all-out sprint cycling test (ASCT) to analyze their relationships. Methods: Thirty male national-level track cyclists participated in this study (n = 30) and performed a 15-s ASCT. The anaerobic power output (Wpeak and Wmean), oxygen uptake, and blood lactate concentrations (La-) were measured. These parameters were used for different calculations of ν La.max and three energy contributions (phosphagen, W PCr; glycolytic, W Gly; and oxidative, W Oxi). The P ν La.max calculation considered delta La-, time until Wpeak (tPCr-peak), and the time contributed by the oxidative system (tOxi). Other ν La.max levels without tOxi were calculated using decreasing time by 3.5% from Wpeak (tPCr -3.5%) and tPCr-peak. Results: The absolute and relative W PCr were higher than W Gly and W Oxi (p < 0.0001, respectively), and the absolute and relative W Gly were significantly higher than W Oxi (p < 0.0001, respectively); ν La.max (tPCr -3.5%) was significantly higher than P ν La.max and ν La.max (tPCr-peak), while ν La.max (tPCr-peak) was lower than P ν La.max (p < 0.0001, respectively). P ν La.max and ν La.max (tPCr-peak) were highly correlated (r = 0.99; R 2 = 0.98). This correlation was higher than the relationship between P ν La.max and ν La.max (tPCr -3.5%) (r = 0.87; R 2 = 0.77). ν La.max (tPCr-peak), P ν La.max, and ν La.max (tPCr -3.5%) were found to correlate with absolute Wmean and W Gly. Conclusion: P ν La.max as a modified calculation of ν La.max provides more detailed insights into the inter-individual differences in energy and glycolytic metabolism than ν La.max (tPCr-peak) and ν La.max (tPCr -3.5%). Because W Oxi and W PCr can differ remarkably between athletes, implementing their values in P ν La.max can establish more optimized individual profiling for elite track cyclists.

Reliability of Low-Cost, Sensor-Based Fine Dust Measurement Devices for Monitoring Atmospheric Particulate Matter Concentrations.

Currently, low-cost, sensor-based fine dust measurement devices are commercially available in South Korea. This study evaluated the reliability of three such devices-Yi Shan A4, Plantower PMS7003, and Plantower PMS7003-in comparison to long-term consecutive monitoring systems for discharge and prevention facilities regarding fine dust control. The performance of these devices for concentration intervals over time was examined through real-time comparison using a GRIMM (Model: 11-A, dust spectrometer from Grimm Technologies) as a reference; this included a correction factor (C-Factor), calculated by a gravimetric method and an equivalence test. For comparison, the reference and target devices were installed in a chamber with fine dust concentrations of 2 µg/m3, with temperature and humidity maintained at 20 °C and 40%, respectively. The fine particulate matter (PM)2.5 concentrations were classified into five intervals: ≤40 µg/m3, 40⁻80 µg/m3, 80⁻120 µg/m3, 120⁻160 µg/m3, and 200⁻230 µg/m3. Statistical analysis was performed using data obtained from national stations for monitoring and controlling fine dust released from facilities under high fine dust loading conditions. The results showed that the measurements of all target devices, which were corrected according to the reference device, provided accurate values at PM2.5 concentrations of ≥40 µg/m3. The statistical analysis results suggest that the evaluated devices are more reliable than the conventional numerical-analysis-based monitoring system.

A preliminary study for conducting a rational assessment of radon exposure levels.

The aim of this study was to determine the factors that go into a highly reliable estimate of radon exposure levels for use in setting up the case-control study. To this end, the present study conducted a multi-faceted investigation of the distribution of radon concentrations in the bedrooms and living rooms of 400 households in the target areas during the winter months from December 2014 to February 2015. We determined that taking the mean value of the radon concentration levels detected in the bedroom and living room as the representative value of residential concentration is appropriate, given the usability of previous research data and the difference in the concentration levels between the two. In terms of detector placement, we found that detectors should not inconvenience residents or be affected by an air current. Further, we found that housing type should distinguish between regular housing (single-detached, row, and multiplex housing) and apartments but that the building type was not a key factor in the assessment of radon exposure levels. Houses should be classified into those constructed with soil (red clay) and those with constructed with general building materials for the assessment of radon exposure levels.

Purification and characterization of a cytosolic Ca(2+)-independent phospholipase A(2) from bovine brain.

The Ca(2+)-independent phospholipase A(2) (iPLA(2)) subfamily of enzymes is associated with arachidonic acid (AA) release and the subsequent increase in fatty acid turnover. This phenomenon occurs not only during apoptosis but also during inflammation and lymphocyte proliferation. In this study, we purified and characterized a novel type of iPLA(2) from bovine brain. iPLA(2) was purified 4,174-fold from the bovine brain by a sequential process involving DEAE-cellulose anion exchange, phenyl-5PW hydrophobic interaction, heparin-Sepharose affinity, Sephacryl S-300 gel filtration, Mono S cation exchange, Mono Q anion exchange, and Superose 12 gel filtration. A single peak of iPLA(2) activity was eluted at an apparent molecular mass of 155 kDa during the final Superose 12 gel-filtration step. The purified enzyme had an isoelectric point of 5.3 on two-dimensional gel electrophoresis (2-DE) and was inhibited by arachidonyl trifluoromethyl ketone (AACOCF(3)), Triton X-100, iron, and Ca(2+). However, it was not inhibited by bromoenol lactone (BEL), an inhibitor of iPLA(2), and adenosine triphosphate (ATP). The spot with the iPLA(2) activity did not match with any known protein sequence, as determined by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis. Altogether, these data suggest that the purified enzyme is a novel form of cytosolic iPLA(2).

Long-term outcome of simultaneous transurethral resection of bladder tumor and prostate in patients with nonmuscle invasive bladder tumor and bladder outlet obstruction.

PURPOSE: We evaluated the long-term outcome of simultaneous transurethral bladder tumor and prostate resection in patients with nonmuscle invasive bladder tumor and bladder outlet obstruction. MATERIALS AND METHODS: Between April 1997 and April 2006, 213 patients with nonmuscle invasive bladder tumor who had a minimum followup of 24 months were included in the study, including group 1-107 with transurethral resection of bladder tumor only and group 2-106 with transurethral bladder tumor and prostate resection. Simultaneous transurethral bladder tumor and prostate resection was performed at surgeon discretion. The records were retrospectively analyzed for clinicopathological parameters, recurrence and progression rates, time to recurrence and postoperative uroflowmetry results in the 2 groups. RESULTS: There were no significant differences in clinicopathological parameters between the 2 groups. At a mean followup of 54.3 and 50.1 months in groups 1 and 2, respectively, group 2 patients with a tumor less than 3 cm or a single tumor had a significantly lower recurrence rate than group 1 patients. None of the 31 patients with recurrence in group 2 had recurrence in the bladder neck or prostatic urethra where transurethral prostate resection had been done. There was no significant difference in the progression rate between the 2 groups. The 60-month recurrence-free probability in groups 1 and 2 was 43.4% and 52.0%, respectively. Three months after surgery the postvoid residual urine volume had significantly decreased in group 2. CONCLUSIONS: Simultaneous transurethral bladder tumor and prostate resection may help decrease bladder cancer recurrence and delay time to recurrence without the risk of cancer implantation when transurethral prostate resection is done, especially in patients with a papillary, solitary-appearing bladder lesion less than 3 cm.

Elastin content of the renal pelvis and ureter determines post-pyeloplasty recovery.

PURPOSE: We evaluated the collagen-to-smooth muscle tissue matrix ratio and percentage of elastin in the renal pelvis, ureteropelvic junction (UPJ) and ureter, and compared these findings with the degree of obstruction, patient age and post-pyeloplasty renal recovery. MATERIALS AND METHODS: We analyzed histological sections from 75 patients with UPJ obstruction. Nine patients were excluded owing to bilateral UPJ obstruction and an improper specimen. We divided the specimen obtained from pyeloplasty into 3 parts, namely the renal pelvis above the obstruction, the obstructed UPJ portion and the ureter below the obstruction. To examine the collagen and smooth muscle, sections were stained using Masson's trichrome, and elastic van Giesson stain was used for elastin, smooth muscle and collagen. Collagen, smooth muscle and elastin populations were identified, and the tissue matrix ratio and percentage of elastin were calculated by color image analysis. RESULTS: In patients with lower ratios of collagen-to-smooth muscle in the UPJ proper hydronephrosis was more improved postoperatively (p = 0.049). In patients with a lower percentage of elastin in the renal pelvis, UPJ and ureter hydronephrosis was more improved postoperatively (p <0.0001). CONCLUSIONS: Because the UPJ portion was resected during pyeloplasty, the renal pelvis and the ureter remaining after pyeloplasty are likely to be related to improved hydronephrosis. A higher percentage of elastin in the renal pelvis and ureter contributes to inelasticity and low compliance, and results in a slower recovery from hydronephrosis after pyeloplasty.