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A novel sample double dilution calibration method (SDDCM) and an automatic flow system with in-syringe reaction and spectrophotometric detection were developed for determining lithium in biological samples. The method is based on the reaction of lithium with Thorin in an alkaline medium and the signal was measured at 480 nm. The reaction was performed simultaneously for both standards and samples in three syringes of the automatic flow system. The method was validated and successfully applied to the determination of lithium in synthetic and pharmaceutical samples, with results consistent with the ICP OES method. The novel calibration method, developed for the determination of lithium in biological samples, uses a sample with two dilution degrees. Using the method, the concentration of the analyte is determined by relating the signal for a less diluted sample to the calibration plot for a more diluted sample and vice versa. The implementation of the calibration method was facilitated by preparing solutions directly in the flow system. The use of two sample dilutions makes it possible to determine the analyte in the sample without preliminary preparation. Moreover, obtaining two results based on signals for a sample diluted to different degrees allows them to be verified for accuracy. The proposed approach was successfully verified by the determination of lithium in certified reference materials of blood serum and urine. Using the developed method lithium was determined within the concentration range of 0.06-1.5 mg L -1 , with precision (CV, %) less than 6.7, and accuracy (RE, %) better than 6.9. The detection limit was 0.03 mg L -1 ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Becker muscular dystrophy (BMD) is an X-linked recessive disorder caused by in-frame deletions in the dystrophin gene (DMD), leading to progressive muscle degeneration and weakness. We generated a human induced pluripotent stem cell (hiPSC) line from a BMD patient. BMD hiPSCs were then engineered by CRISPR/Cas9-mediated knock-in of missing exons 3-9 of DMD gene. Obtained hiPSC line may be a valuable tool for investigating the mechanisms underlying BMD pathogenesis., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dulak reports financial support was provided by National Science Centre Poland. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Due to increasing life expectancy incidence of neurological disorders is rapidly rising, thus adding urgency to develop effective strategies for treatment. Stem cell-based therapies were considered highly promising and while progress in this field is evident, outcomes of clinical trials are rather disappointing. Suboptimal engraftment, poor cell survival and uncontrolled differentiation may be the reasons behind dismal results. Clearly, new direction is needed and we postulate that with recent progress in biomaterials and bioprinting, regenerative approaches for neurological applications may be finally successful. The use of biomaterials aids engraftment of stem cells, protects them from harmful microenvironment and importantly, it facilitates the incorporation of cell-supporting molecules. The biomaterials used in bioprinting (the bioinks) form a scaffold for embedding the cells/biomolecules of interest, but also could be exploited as a source of endogenous contrast or supplemented with contrast agents for imaging. Additionally, bioprinting enables patient-specific customization with shape/size tailored for actual needs. In stroke or traumatic brain injury for example lesions are localized and focal, and usually progress with significant loss of tissue volume creating space that could be filled with artificial tissue using bioprinting modalities. The value of imaging for bioprinting technology is advantageous on many levels including design of custom shapes scaffolds based on anatomical 3D scans, assessment of performance and integration after scaffold implantation, or to learn about the degradation over time. In this review, we focus on bioprinting technology describing different printing techniques and properties of biomaterials in the context of requirements for neurological applications. We also discuss the need for in vivo imaging of implanted materials and tissue constructs reviewing applicable imaging modalities and type of information they can provide. STATEMENT OF SIGNIFICANCE: Current stem cell-based regenerative strategies for neurological diseases are ineffective due to inaccurate engraftment, low cell viability and suboptimal differentiation. Bioprinting and embedding stem cells within biomaterials at high precision, including building complex multi-material and multi-cell type composites may bring a breakthrough in this field. We provide here comprehensive review of bioinks, bioprinting techniques applicable to application for neurological disorders. Appreciating importance of longitudinal monitoring of implanted scaffolds, we discuss advantages of various imaging modalities available and suitable for imaging biomaterials in the central nervous system. Our goal is to inspire new experimental approaches combining imaging, biomaterials/bioinks, advanced manufacturing and tissue engineering approaches, and stimulate interest in image-guided therapies based on bioprinting., (Copyright © 2019. Published by Elsevier Ltd.)

The year 2016 marked the 125th anniversary of the birth of physician-venereologist and passionate writer Mikhail Afanasievich Bulgakov (1891-1940). From his essays emerges a figure of a man torn between medicine and literature. His works contain fragments pertaining to his personal ailments and health problems, which are described with medical precision, for example, morphine addiction. Bulgakov's essays are full of metaphors and references to the political situation of Soviet Russia. He compared this situation to syphilis as in treacherous infections, a slow destroying and enslaving of a social organism., (Copyright © 2017.)

Purpose: The purpose of this study was to investigate the influence of selective agonists of the retinoid receptor X (RXR) and the retinoid acid receptor (RAR) on bone metabolism in rats., Methods: Thirty six male Wistar rats were divided into three groups: receiving bexarotene, or tazarotene, or to control group. Serum biochemical markers of bone turnover (osteocalcin - OC, tartrate resistant acid phosphatase 5 - TRACP5b and osteoprotegerin - OPG) and mechanical properties of bones were analyzed., Results: There was a significant decrease in the femur index value in groups receiving tazarotene and bexarotene on Day 14 (8% and 20% respectively, p=0.0039). On Day 28, 14 days after discontinuation of tazarotene and bexarotene, the difference in femur indexes was still significant (4% for T1-6 and B1-6, p=0.0270). In the bexarotene group an increase in mean plasma osteocalcin level and mean plasma TRACP5b level was detected. In the tazarotene group the mean osteocalcin level remained unchanged and the mean plasma TRACP5b level decreased. An increased yield stress was detected in groups receiving retinoids comparing to controls after 14 days of tazarotene and bexarotene administration., Conclusion: Although bexarotene and tazarotene administration caused decrease in the femur index, mechanisms responsible for that effect seem to be different. Our results suggest that bexaroten increases bone turnover. On the contrary, tazaroten seems to have inhibitory effect on bone turnover. A counter influence of selective RAR and RXR agonists on the bone turnover might be the reason for inconsistency in results from published research concerning the influence of retinoids on bone metabolism., (Copyright © 2015 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.)

In natural environments, bacteria are often challenged by nutrient starvation and other stresses. As a consequence, cell growth is arrested and bacteria enter stationary phase. In this report, we demonstrate that during stationary phase, Escherichia coli cells accumulate aggregates of misfolded proteins and complexes of Dps (starvation-induced protein) with chromosomal DNA. We found that the formation of multicomponent protein aggregates and insoluble Dps-DNA complexes depended on growth conditions and was influenced by the availability of oxygen and glucose in a medium. Aerobic stationary cells grown in unbuffered medium supplemented with glucose contained insoluble Dps-DNA, whereas multicomponent protein aggregates were accumulated under glucose starvation. On the contrary, under oxygen depletion, Dps-DNA complexes were formed in the absence of glucose, whereas multicomponent protein aggregates appeared in the presence of glucose. The mechanisms responsible for this phenomenon remain to be elucidated; however, we demonstrated that in MOPS-buffered cultures the level of insoluble Dps and protein aggregates was decreased.

Erythrocyte glucose-6-phosphate dehydrogenase from patients with acute viral hepatitis has been purified and characterized. The enzyme showed decreased activity (relative to protein), reduced affinity for glucose 6-phosphate and was inactivated at 45 degrees C or at low pH values. The activity and properties of normal erythrocyte enzyme, incubated in vitro with blood plasma of patients, showed a similar pattern of modifications. Incubation with bilirubin affected the enzyme stability, but not its activity or affinity for substrate.