Erratum: Publisher's Note: "Magneto-responsive hyaluronan hydrogel for hyperthermia and bioprinting: Magnetic, rheological properties and biocompatibility" [APL Bioeng. 7, 036113 (2023)].

[This corrects the article DOI: 10.1063/5.0147181.].

Magneto-responsive hyaluronan hydrogel for hyperthermia and bioprinting: Magnetic, rheological properties and biocompatibility.

Magneto-responsive soft hydrogels are used for a number of biomedical applications, e.g., magnetic hyperthermia, drug delivery, tissue engineering, and neuromodulation. In this work, this type of hydrogel has been fabricated from hyaluronan (HA) filled with a binary system of Al2O3 nanoparticles and multicore magnetic particles (MCPs), which were obtained by clustering of superparamagnetic iron oxide FeOx NPs. It was established that the presence of diamagnetic Al2O3 has several positive effects: it enhances the hydrogel storage modulus and long-term stability in the cell cultivation medium; prevents the magnetic interaction among the MCPs. The HA hydrogel provides rapid heating of 0.3 °C per min under exposure to low amplitude radio frequency alternating magnetic field. Furthermore, the magneto-responsive hydrogel was successfully used to encapsulate cells and extrusion-based 3D printing with 87±6% cell viability, thus providing a bio-ink. The combination of high heating efficiency, softness, cytocompatibility, and 3D printability of magnetic HA hydrogel leads to a material suitable for biomedical applications.

Pseudomonas moraviensis subsp. stanleyae, a bacterial endophyte of hyperaccumulator Stanleya pinnata, is capable of efficient selenite reduction to elemental selenium under aerobic conditions.

AIMS: To identify bacteria with high selenium tolerance and reduction capacity for bioremediation of wastewater and nanoselenium particle production. METHODS AND RESULTS: A bacterial endophyte was isolated from the selenium hyperaccumulator Stanleya pinnata (Brassicaceae) growing on seleniferous soils in Colorado, USA. Based on fatty acid methyl ester analysis and multi-locus sequence analysis (MLSA) using 16S rRNA, gyrB, rpoB and rpoD genes, the isolate was identified as a subspecies of Pseudomonas moraviensis (97.3% nucleotide identity) and named P. moraviensis stanleyae. The isolate exhibited extreme tolerance to SeO3(2-) (up to 120 mmol l(-1)) and SeO4(2-) (>150 mmol l(-1)). Selenium oxyanion removal from growth medium was measured by microchip capillary electrophoresis (detection limit 95 nmol l(-1) for SeO3(2-) and 13 nmol l(-1) for SeO4(2-)). Within 48 h, P. moraviensis stanleyae aerobically reduced SeO3(2-) to red Se(0) from 10 mmol l(-1) to below the detection limit (removal rate 0.27 mmol h(-1) at 30 °C); anaerobic SeO3(2-) removal was slower. No SeO4(2-) removal was observed. Pseudomonas moraviensis stanleyae stimulated the growth of crop species Brassica juncea by 70% with no significant effect on Se accumulation. CONCLUSIONS: Pseudomonas moraviensis stanleyae can tolerate extreme levels of selenate and selenite and can deplete high levels of selenite under aerobic and anaerobic conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Pseudomonas moraviensis subsp. stanleyae may be useful for stimulating plant growth and for the treatment of Se-laden wastewater.

Analysis of genetic variability in the Czech Dachshund population using microsatellite markers.

The primary goal of this study was to analyse genetic variation within and among six Dachshund varieties in the Czech Republic using 10 microsatellites from StockMarks Paternity Polymerase Chain Reaction (PCR) Typing kit. A total of 632 Dachshunds were sampled - 99 Standard Smooth-haired, 72 Standard Long-haired, 272 Standard Wire-haired, 42 Miniature Smooth-haired, 73 Miniature Long-haired and 74 Miniature Wire-haired. Average observed heterozygosity and polymorphic information content ranged in particular Dachshund varieties between 0.58-0.70 and 0.57-0.64, respectively. Subsequent analysis of the population structure (F-statistics; Nei's genetic identity) showed that Standard Dachshunds shared allele frequencies most closely with their miniature equivalents, and smooth coat type is closer to Wire-haired coat type than to the Long-haired one. Analysis of molecular variance revealed that 11.81% of the total variance occurred among varieties. The value of combined exclusion probability (0.9955) validated usefulness of this panel of microsatellites for parentage verification in all analysed populations. We carried out 234 parentage verifications with 1.28% cases where parentage did not match.

Potency of several oximes to reactivate human acetylcholinesterase and butyrylcholinesterase inhibited by paraoxon in vitro.

Organophosphorus pesticides (e.g. chlorpyrifos, malathion, and parathion) and nerve agents (sarin, tabun, and VX) are highly toxic organophosphorus compounds with strong inhibition potency against two key enzymes in the human body-acetylcholinesterase (AChE; EC 3.1.1.7) and butyrylcholinesterase (BuChE; EC 3.1.1.8). Subsequent accumulation of acetylcholine at synaptic clefts can result in cholinergic crisis and possible death of intoxicated organism. For the recovery of inhibited AChE, derivatives from the group of pyridinium or bispyridinium aldoximes (called oximes) are used. Their efficacy depends on their chemical structure and also type of organophosphorus inhibitor. In this study, we have tested potency of selected cholinesterase reactivators (pralidoxime, obidoxime, trimedoxime, methoxime and H-oxime HI-6) to reactivate human erythrocyte AChE and human plasma BuChE inhibited by pesticide paraoxon. For this purpose, modified Ellman's method was used and two different concentrations of oximes (10 and 100 microM), attainable in the plasma within antidotal treatment of pesticide intoxication were tested. Results demonstrated that obidoxime (96.8%) and trimedoxime (86%) only reached sufficient reactivation efficacy in case of paraoxon-inhibited AChE. Other oximes evaluated did not surpassed more than 25% of reactivation. In the case of BuChE reactivation, none of tested oximes surpassed 12.5% of reactivation. The highest reactivation efficacy was achieved for trimedoxime (12.4%) at the concentration 100 microM. From the data obtained, it is clear that only two from currently available oximes (obidoxime and trimedoxime) are good reactivators of paraoxon-inhibited AChE. In the case of BuChE, none of these reactivators could be used for its reactivation.

Effects of stress on serum prolactin levels in patients with systemic lupus erythematosus.

The results of a study of effects of stress on serum prolactin (PRL) levels in patients with SLE reveal statistically significant differences in serum PRL level readings in samples taken over a short period of time, thus corroborating the need to take into account PRL stress induction during sample withdrawals and to interpret the values obtained, especially where moderate idiopathic hyperprolactinemia was detected. To eliminate any external stress factors, it is advisable to take PRL samples repeatedly and in perfectly resting patients.

Hyperprolactinaemia in patients with systemic lupus erythematosus.

OBJECTIVE: To verify the presence of hyper-PRL in SLE patients, its association with high disease activity, specific organ involvement or presence of anti-ds-DNA antibodies. METHODS: The group under study consisted of 80 patients with systemic lupus erythematosus (SLE), 28 patients with rheumatoid arthritis (RA) and 27 healthy controls. PRL serum levels were assayed using standard commercial kits (Immunotech Prague) with the radioimmunometric method for testing three samples of each of the subjects. The samples were taken in the morning hours (9-11 a.m.) of absolute rest 30 minutes after the introduction of the cannula at 30-minute intervals. RESULTS: A significantly higher rate of elevated PRL levels was found in SLE patients (40.0%) compared with the healthy controls (14.8%, p < 0.017). No proof was found of association with the presence of anti-ds-DNA or with specific organ involvement. Similarly, elevated PRL levels were found in RA patients (39.3%). The PRL elevation tended to decline from the 1st to the 3rd sample in the group of patients with SLE and RA but not in healthy controls. CONCLUSION: As follows from our measurements of prolactin serum values in SLE patients they are varriable by definition. According to our opinion further investigations are needed.