Peripheral blood lymphocyte immunophenotyping (TBNK) - a comparison of BD FACSCanto II and BD FACSLyric flow cytometry analysers.

Introduction: Flow cytometry immunophenotyping is a common laboratory technique for evaluating lymphocyte subpopulations. Its result remains an important diagnostic tool in various medical fields. Cytometric tests are performed in many laboratories, making the comparability between different devices using the same method an important aspect. We aimed to compare the results of lymphocyte immunophenotyping (lymphocytes B, T, Th and Tc, NK cells) between two different flow cytometers. Material and methods: The study included 93 patients of the Children's Teaching Hospital of the Medical University of Warsaw and 9 Multi-Check control results. The method of lymphocyte subpopulation assessment was based on fluorescent flow cytometry immunophenotyping, using a BD Multitest 6-color TBNK kit (Becton Dickinson). We compared BD FACSCanto II and BD FACSLyric analysers (Becton Dickinson). For data analysis, we used Spearman's rank correlation, Bland-Altman plot and Passing-Bablok regression. Results: Spearman's rank correlation showed a strong interrelation for all analysed parameters (0.808-0.985). In the Passing-Bablok regression analysis, all examined parameters showed linear dependence with the slope values close to 1 (0.940-1.134). Bland-Altman coefficient values were within the range of 2.94-8.62% with half of them being above 5% (T, Tc, Th, B, NKT absolute values and B percentage values). Conclusions: The results from both cytometers can be considered equivalent, but it should be noted that one of the statistical methods showed some deviations, presumably primarily due to the evaluators' different gating techniques. The training of specialists performing these tests requires more attention.

Organ-Dysfunction Markers in Mild-to-Moderate COVID-19 Convalescents.

Background: A coronavirus disease 2019 (COVID-19) outbreak led to a worldwide pandemic. COVID-19 not only caused acute symptoms during the severe phase of the disease, but also induced long-term side effects on the functioning of many organs and systems. Symptoms that were associated with the disease and present at least 3 months after recovery were named long COVID. The aim of this study was to assess if mild-to-moderate COVID-19 may lead to the dysfunction of respiratory, cardiovascular, neural, and renal systems in healthy blood donors who recovered from the disease at least 6 months earlier. Methods: Here, we examined 294 adults among volunteer blood donors divided into convalescents (n = 215) and healthy controls (n = 79). Concentrations of soluble CD163, TGF beta, Lp-PLA2, NCAM-1, S100, NGAL, and creatinine were measured either by ELISA or automated methods. The probability value p < 0.05 was considered as statistically significant. Results: We found significant differences in Lp-PLA2, S100, and NCAM-1 between convalescents and never-infected subjects. Lp-PLA2 and NCAM-1 were lower, and S100 higher, in convalescents than in the control group. Conclusion: Mild-to-moderate COVID-19 convalescents are at a low risk of developing lung fibrosis or chronic kidney disease. However, they should regularly carry out their prophylaxis examinations for early detection of possible negative outcomes of COVID-19.

Lethal perturbation of an Escherichia coli regulatory network is triggered by a restriction-modification system's regulator and can be mitigated by excision of the cryptic prophage Rac.

Bacterial gene regulatory networks orchestrate responses to environmental challenges. Horizontal gene transfer can bring in genes with regulatory potential, such as new transcription factors (TFs), and this can disrupt existing networks. Serious regulatory perturbations may even result in cell death. Here, we show the impact on Escherichia coli of importing a promiscuous TF that has adventitious transcriptional effects within the cryptic Rac prophage. A cascade of regulatory network perturbations occurred on a global level. The TF, a C regulatory protein, normally controls a Type II restriction-modification system, but in E. coli K-12 interferes with expression of the RacR repressor gene, resulting in de-repression of the normally-silent Rac ydaT gene. YdaT is a prophage-encoded TF with pleiotropic effects on E. coli physiology. In turn, YdaT alters expression of a variety of bacterial regulons normally controlled by the RcsA TF, resulting in deficient lipopolysaccharide biosynthesis and cell division. At the same time, insufficient RacR repressor results in Rac DNA excision, halting Rac gene expression due to loss of the replication-defective Rac prophage. Overall, Rac induction appears to counteract the lethal toxicity of YdaT. We show here that E. coli rewires its regulatory network, so as to minimize the adverse regulatory effects of the imported C TF. This complex set of interactions may reflect the ability of bacteria to protect themselves by having robust mechanisms to maintain their regulatory networks, and/or suggest that regulatory C proteins from mobile operons are under selection to manipulate their host's regulatory networks for their own benefit.

Molecular basis for lethal cross-talk between two unrelated bacterial transcription factors - the regulatory protein of a restriction-modification system and the repressor of a defective prophage.

Bacterial gene expression depends on the efficient functioning of global transcriptional networks, however their interconnectivity and orchestration rely mainly on the action of individual DNA binding proteins called transcription factors (TFs). TFs interact not only with their specific target sites, but also with secondary (off-target) sites, and vary in their promiscuity. It is not clear yet what mechanisms govern the interactions with secondary sites, and how such rewiring affects the overall regulatory network, but this could clearly constrain horizontal gene transfer. Here, we show the molecular mechanism of one such off-target interaction between two unrelated TFs in Escherichia coli: the C regulatory protein of a Type II restriction-modification system, and the RacR repressor of a defective prophage. We reveal that the C protein interferes with RacR repressor expression, resulting in derepression of the toxic YdaT protein. These results also provide novel insights into regulation of the racR-ydaST operon. We mapped the C regulator interaction to a specific off-target site, and also visualized C protein dynamics, revealing intriguing differences in single molecule dynamics in different genetic contexts. Our results demonstrate an apparent example of horizontal gene transfer leading to adventitious TF cross-talk with negative effects on the recipient's viability. More broadly, this study represents an experimentally-accessible model of a regulatory constraint on horizontal gene transfer.

The role of vitamin D in selected autoimmune diseases.

The authors of recently published scientific papers are focusing increasingly often on the effect of vitamin D on immune processes. In the case of deficiencies of this vitamin, an imbalance in the immune system is observed, which is associated with the intensification of the inflammatory reaction in the body and the increased possibility of an autoimmune reaction. Therefore, due to the growing interest of scientists in the relationship between the effects of vitamin D and the development of autoimmune diseases, this paper considers the use of Vitamin D in autoimmune therapies. However, the mechanism of vitamin D on individual autoimmune diseases has not been elucidated so far, therefore there is a need for further research. The importance of maintaining normal plasma vitamin D levels to reduce the risk of developing autoimmune diseases has been demonstrated by the authors of other studies. They showed that vitamin D levels influenced the course, severity of symptoms and frequency of relapses of autoimmune thyroid disease, inflammatory bowel disease, and rheumatoid arthritis.

Structural and spectroscopic analysis of a new family of monomeric diphosphinoboranes.

We present a series of amino- and aryl(diphosphino)boranes R2PB(R'')PR'2, where R2P, R'2P = tBu2P, tBuPhP, Ph2P, Cy2P, and R'' = iPr2N, Ph, which were obtained via the metathesis reaction of iPr2NBBr2 or PhBBr2 with selected lithium phosphides. The structures of isolated diphosphinoboranes were characterized in the solid state and in solution by means of X-ray diffraction and NMR spectroscopy, respectively. The utility of these P-B-P species as ligands for transition metal complexes was tested in the reaction with [(COD)PtMe2]. Moreover, we carried out DFT calculations to elucidate bonding interactions and philicity of the reactive centers as well as to analyze conformations of the studied species. Electronic and steric properties of substituents on P and B atoms were found to have a strong influence on the structures of the obtained compounds. Three main types of diphosphinoboranes were distinguished, based on the strength of P-B π-interaction within the molecule: (i) application of strong electron-donating substituents on P-atoms and electron-accepting phenyl groups on B atoms led to the structure with one double P[double bond, length as m-dash]B and one single P-B bond and diverse planar and pyramidal geometry of phosphanyl groups; (ii) reduction of the donor ability of phosphanyl groups gave diphosphanylboranes with delocalized P-B-P π-interactions; (iii) introduction of amino groups with strong donor abilities on B atoms canceled P-B π-interactions and allowed compounds with two very long P-B bonds and two pyramidal phosphanyl groups to be obtained.

Reactions of (Ph)tBuP-P(SiMe3)Li·3THF with [(PNP)TiCl2] and [MeNacNacTiCl2·THF]: synthesis of first PNP titanium(iv) complex with the phosphanylphosphinidene ligand [(PNP)Ti(Cl){η2-P-P(Ph)tBu}].

Herein, the lithium derivative of diphosphane, (Ph)tBuP-P(SiMe3)Li (1), is isolated for the first time and investigated in reactions with ß-diketiminate (MeNacnac- = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-iPr2C6H3) and PNP-pincer (PNP = N[2-PiPr2-4-methylphenyl]2) Ti(iii) complexes. The ß-diketiminate titanium(iii) complex containing the phosphanylphosphido ligand [MeNacNacTi(Cl){η2-P(SiMe3)-P(Ph)tBu}] (2) is prepared via the reaction of [MeNacNacTiCl2·THF] with (Ph)tBuP-P(SiMe3)Li in toluene solution with good yield and purity. The corresponding titanium(iv) complex involving the phosphanylphosphinidene ligand [MeNacNacTi(Cl){η2-P-P(Ph)tBu}] (3) is synthesized via the oxidation of complex (2) with [iBu3PAgCl]4. Interestingly, an analogous PNP titanium(iv) complex, [(PNP)Ti(Cl){η2-P-P(Ph)tBu}] (4), is obtained in the reaction of [(PNP)TiCl2] with (Ph)tBuP-P(SiMe3)Li in toluene solution and a 1 : 1 molar ratio instead of the expected titanium(iii) complex with the phosphanylphosphido ligand. The solid-state structures of (Ph)tBuP-P(SiMe3)Li·3THF (1), [MeNacNacTi(Cl){η2-P(SiMe3)-P(Ph)tBu}] (2), [MeNacNacTi(Cl){η2-P-P(Ph)tBu}] (3) and [(PNP)Ti(Cl){η2-P-P(Ph)tBu}] (4) are determined by single-crystal X-ray diffraction, which reveals that in all obtained complexes, both the phosphanylphosphinidene (Ph)tBuP-P and phosphanylphosphido (Ph)tBuP-P(SiMe3) ligands are bidentate-coordinated to the metal center.

Antifungal dipeptides incorporating an inhibitor of homoserine dehydrogenase.

The antifungal activity of 5-hydroxy-4-oxo-l-norvaline (HONV), exhibited under conditions mimicking human serum, may be improved upon incorporation of this amino acid into a dipeptide structure. Several HONV-containing dipeptides inhibited growth of human pathogenic yeasts of the Candida genus in the RPMI-1640 medium, with minimal inhibitory concentration values in the 32 to 64 µg mL-1 range. This activity was not affected by multidrug resistance that is caused by overexpression of genes encoding drug efflux proteins. The mechanism of antifungal action of HONV dipeptides involved uptake by the oligopeptide transport system, subsequent intracellular cleavage by cytosolic peptidases, and inhibition of homoserine dehydrogenase by the released HONV. The relative transport rates determined the anticandidal activity of HONV dipeptides.

Silver complexes stabilized by large silanethiolate ligands - crystal structures and luminescence properties.

Bulky silanethiolate and disiladithiolate ligands were applied to synthesize one mononuclear and three trinuclear silver complexes including two cyclic "microclusters" and a linear tri-nuclear silanethiolate complex. All obtained compounds are characterized by X-ray diffraction and FT-IR. NMR and emission spectroscopies were used where possible. The first trinuclear anionic silver thiolate is structurally characterized. The influence of the different charge of cyclic silver complexes as well as the overall ligand environment on the structural properties is demonstrated. The impact of the different synthetic routes on the final structures of the obtained clusters - cyclic or linear - is discussed.

Syntheses and structures of the first terminal phosphanylphosphido complex of hafnium [Cp2Hf(Cl){η(1)-(Me3Si)P-P(NEt2)2}] and the first zirconocene-phosphanylphosphinidene dimer [Cp2Zr{µ(2)-P-P(NEt2)2}2ZrCp2].

Reactions of (Et(2)N)(2)P-P(SiMe(3))Li with [Cp(2)MCl(2)] (M = Zr, Hf) in toluene or pentane yield the related terminal phosphanylphosphido complexes [Cp(2)M(Cl){η(1)-(Me(3)Si)P-P(NEt(2))(2)}]. The solid state structure of [Cp(2)Hf(Cl){η(1)-(Me(3)Si)P-P(NEt(2))(2)}] was established by single crystal X-ray diffraction. The reaction of (Et(2)N)(2)P-P(SiMe(3))Li with [Cp(2)ZrCl(2)] in THF or DME solutions leads to the formation of deep red crystals of the first neutral diamagnetic zirconocene-phosphanylphosphinidene dimer [Cp(2)Zr{µ(2)-P-P(NEt(2))(2)}(2)ZrCp(2)]. The molecular structure of this compound was confirmed by X-ray diffraction. The reactions of (R(2)N)(2)P-P(SiMe(3))Li with [CpZrCl(3)] yield the related tetraphosphetanes R(2)NP(µ(2)-PSiMe(3))(2)PNR(2), which apparently are formed as a result of a transfer of NR(2) groups from a P atom to the Zr atom.

Dichlorido-1κCl,3κCl-hexa-kis[1,1,2,2,3,3(η)-methyl-cyclo-penta-dienyl]di-µ(2)-oxido-1:2κO:O;2:3κO:O-trihafnium(IV).

The title compound, [Hf(3)(C(6)H(7))(6)Cl(2)O(2)], is a trinuclear mol-ecule having two (MeCp)(2)HfCl units (MeCp is methyl-cyclo-penta-dien-yl) each connected to an (MeCp)(2)Hf unit by an oxide bridge. The two Hf-O-Hf bridges are nearly linear. The geometry of the three Hf atoms is tetra-hedral (assuming the MeCp group occupies one coordination site); the O-Hf-O angle is 99.8 (5)°. One of the Cl atoms is disordered, with site occupancies of 0.61 (7) and 0.39 (7).

trans-Dichloridobis(triisopropyl-phosphine-κP)palladium(II).

The title compound, [PdCl(2)(C(9)H(21)P)(2)], is a centrosymmetric mononuclear palladium(II) complex. The Pd(II) atom, which lies on an inversion center, is in a square-planar geometry.

(Di-tert-butyl-phosphan-yl)bis-(diphenyl-phosphan-yl)phosphane.

The title phosphane, C(32)H(38)P(4) or (Ph(2)P)(2)P(P(t)Bu(2)), has a P atom that is linked to another three P atoms in a pyramidal configuration; the P-P distances in the range 2.2231 (7)-2.2446 (7) Šindicate that the P-P bonds are single bonds.