Life-On-Hold: Lanthanoids Rapidly Induce a Reversible Ametabolic State in Mammalian Cells

Until now, the ability to reversibly halt cellular processes has been limited to cryopreservation and several forms of anabiosis observed in living organisms. In this paper we show that incubation of living cells with a solution containing ~50 mM neodymium induces a rapid shutdown of intracellular organelle movement and all other evidence of active metabolism. We have named this state REEbernation (derived from the terms REE (rare earth elements) and hibernation) and found that the process involves a rapid replacement of calcium with neodymium in membranes and organelles of a cell, allowing it to maintain its shape and membrane integrity under extreme conditions, such as low pressure. Furthermore, phosphate exchange is blocked as a result of non-dissolvable neodymium salts formation, which “discharged” the cell. We further showed that REEbernation is characterized by an immediate cessation of transcriptional activity in observed cells, providing an intriguing opportunity to study a snapshot of gene expression at a given time point. Finally, we found that the REEbernation state is reversible, and we could restore the metabolism and proliferation capacity of the cells. The REEbernation, in addition to being an attractive model to further investigate the basic mechanisms of cell metabolism control, also provides a new method to reversibly place a cell into “on-hold” mode, opening opportunities to develop protocols for biological samples fixation with a minimum effect on the omics profile for biomedical needs.

Relationships between phosphatemia/phosphaturia and EEG/HRV parameters in patients with chronic pyelonephritis

Background. As part of the project "Relationships between parameters of electrolytes exchange and EEG&HRV in people without kidney disease and patients with chronic pyelonephritis" we have previously shown that parameters of calcium exchange and EEG/HRV are closely related. In this study, we analyzed the relationships between parameters of phosphate exchange and EEG/HRV in the same cohort of patients. Material and methods. The object of observation were 48 males and 15 females 24-76 years old, who came to the spa Truskavets’ (Ukraine) for the treatment of chronic pyelonephritis in remission. We recorded simultaneosly EEG (“NeuroCom Standard”) and electrocardiogram ("CardioLab+HRV") in II lead to assess the parameters of HRV. Phosphate concentration was determined in blood plasma and daily urine. Results. It was stated normal or moderately reduced plasma phosphate levels in combination with a very wide range of phosphate urinary excretion. A very strong canonical correlation was found between phosphatemia and EEG/HRV parameters (R=0,982). The correlations with the parameters of the beta and theta rhythms of the EEG and the HRV are positive, while with the parameters of the delta rhythm of the EEG are negative. The canonical correlation between phosphaturia and EEG parameters is also very strong (R=0,879). Conclusion. Parameters of phosphate exchange and EEG/HRV are closely related, however the question of the causal nature of correlations remains open.

Vitamin D Effects on Guided Bone Regeneration and Osseointegration of Dental Implants (Literature Review)

Background.Due to the prevalence of Vitamin D deficiency as well as the frequency of reconstructive surgical interventions followed by dental implantation, the issue arises concerning the effect of Vitamin D on reparative regeneration of bone and osseointegration of dental implants.The purpose using literature data we are conducting an impact assessment of vitamin D on reparative regeneration of bone tissue, in particular, after oral reconstruction surgeries and dental implantation.Methods.Retrieval, systematization and analysis of scientific data on application of vitamin D supplementation and its effect on reparative regeneration of jaw bone tissue.The conclusions.For the most part, the positive effect exerted on reparative regeneration of jaw bone tissue and osseointegration of dental implants is due to the role of vitamin D in physiological processes evolving in bone tissue, namely maintenance of calcium and phosphate exchange through intestinal absorption and TNF, RANKL (Receptor activator of nuclear factor kappa-B ligand) and consequently differentiation of precursors to osteoclasts into osteoclasts through VDR stimulation (VitaminD Receptor) receptors for further osteogenesis. Also, according to literature data, FGF23 (Fibroblast Growth Factor) protein is a marker of osteoblasts differentiation into osteocytes, it is also known that FGF23 and 1,25(ОН)2D3 are genetically related. FGF23 is the main regulator of both phosphate exchange in bones and metabolism of vitamin D and its metabolites. Besides, indirect anti-inflammatory effect has been observed thanks to inhibition of pro-inflammatory cytokine secretion. Taking into account the abovementioned data, of particular relevance is the definition of serum concentration 25(ОН)D and development of schemes of vitamin D level pre-surgery correction in patients, who have to undergo oral reconstruction surgeries and dental implantation. Mass spectrometry is a promising diagnostic method for determining the level of vitamin D in a body, as it allows to identify the actual amount of vitamin D free from admixture of other steroid hormones. The introduction of this method into clinical practice will allow to monitor the level of vitamin D in patients, receiving reconstructive and rehabilitative treatment.

Biochar-Ca and Biochar-Al/-Fe-Mediated Phosphate Exchange Capacity are Main Drivers of the Different Biochar Effects on Plants in Acidic and Alkaline Soils

Because of the low consistency of the results obtained in the field, the use of biochar as a soil amendment is controversial. Thus, in general, in acidic soils, results are positive, while in alkaline soils, they are non-significant or even negative. The results regarding biochar action in acidic soils have been related to a lime-like effect due to its alkaline pH and the high doses normally used. However, the causes of biochar effects in alkaline soils remain unknown. Our objective was to explore the chemical mechanism of biochar interaction in acidic and alkaline soils. We used well-characterized biochar as a component of two complex N and PK granulated fertilizers at two different doses (1% and 5%). These fertilizers were applied to wheat cultivated in pots containing an alkaline soil and grown for 60 days. No effect was shown for the N-biochar fertilizer application. However, the PK-biochar fertilizer application caused a decrease in crop yield. In addition, the adsorption isotherms of Al, Fe, Mo, Mn, and Phosphate (Pi) in biochar were also studied. The results showed that Fe and Al were rapidly adsorbed in biochar, while Pi was only adsorbed on the Fe-, Al-biochar complex. Desorption experiments showed that P and Fe/Al were not desorbed from the P-Fe/Al-biochar complex by water or the Olsen reagent, while partial desorption was observed when HCl 0.1 M was used. This blockage of Fe/Al and P through Fe/Al bridges in biochar could partially explain the negative effects in alkaline soils. After these studies, soil solution sorption experiments were carried out in both acidic and alkaline soils and were complemented with a greenhouse trial using tomato plants. The results showed that biochar enhanced foliar Ca and N content, as well as growth in acidic soil only, and the possible mechanism of the failure in alkaline soils.

HIDDEN COMPLICATIONS OF THE POSTOPERATIVE PERIOD: DIAGNOSIS AND TREATMENT

One of the hidden complications of the postoperative period is hypophosphatemia (HPE), which often develops imperceptibly, but can worsen the overall results of treatment. The objective of the work: to investigate the frequency of development of disorders of phosphate exchange in the postoperative period and to establish the possibility and effectiveness of correction of such violations. Materials and methods. The determination of phosphate levels was carried out in 328 patients undergoing surgical treatment in surgical operations of various surgical status. Results. The highest rate of HPE was observed in patients with burns (23.08 %), after neurosurgical (17.94 %) and abdominal (17.64 %) surgical interventions. It is established that the correction of severe HPE is advisable by intravenous administration of sodium D-fructose-1,6-diphosphate. Conclusion. In the postoperative period, HPE is common, but is successfully corrected to abstract values, which coincides with the clinical improvement of patients.

Phosphate exchange across the sediment-water interface under oxic and hypoxic/anoxic conditions in the southern Baltic Sea

Benthic fluxes of phosphate and phosphorus distribution in sediments from the southern Baltic Sea were investigated in spring and autumn in 2005 and 2007–2010. Strong spatial variability of phosphate fluxes was observed across the sediment-water interface. The highest values of phosphate flux from sediment (up to 37 μmol m−2 h−1), resulting from the high mineralization rate of organic matter and rapid phosphorus turnover due to macrofaunal activity and hydrodynamic conditions, were observed in the shallow area at depths ranging from 50 to 69 m. The rate of phosphate exchange in the transportation and accumulation bottom area with the water depth ≥72 m was several times lower (2.12–6.22 μmol m−2 h−1). In continuously hypoxic or anoxic sediments, phosphorus was preserved in the refractory organic form, and sediments were depleted of redox-dependent phosphorus forms. In shallow area with well oxygenated near-bottom water, phosphorus was present mainly in the calcium-bound form.