N-terminal brain natriuretic propeptide levels correlate with procalcitonin and C-reactive protein levels in septic patients

The aim of this study was to find the relationship between N-terminal brain natriuretic propeptide (NT-proBNP), procalcitonin (PCT) and C-reactive protein (CRP) plasma concentrations in septic patients. This was a prospective study, performed at Medical University Hospital No. 5 in łódź. Twenty patients with sepsis and severe sepsis were included in the study. N-terminal brain natriuretic propeptide, procalcitonin and C-reactive protein concentrations, and survival were evaluated. In the whole studied group (128 measurements), the mean NT-proBNP, procalcitonin and C-reactive protein concentrations were, respectively: 140.80±84.65 pg/ml, 22.32±97.41 ng/ml, 128.51±79.05 mg/l. The correlations for the NT-proBNP level and procalcitonin and C-reactive protein levels were 0.3273 (p<0.001) and 0.4134 (p<0.001), respectively. NT-proBNP levels correlate with PCT and CRP levels in septic patients. In the survivor subgroup, the mean NT-proBNP plasma concentrations were significantly lower than in the non-survivor subgroup.     

Assignment of the absolute configuration of P-chiral 5' mRNA cap analogues containing phosphorothioate moiety

Enzymatic cleavage of the P-chiral diastereoisomers of the 5' mRNA cap analogue bearing phosphorothioate moiety in alfa position of 5',5'-triphosphate bridge (m(7)Gppp(S)G D1 and D2) was performed by human Decapping Scavenger (DcpS) enzyme. Analysis of the degradation products allowed to estimate the absolute configuration at the asymmetric phosphorus atoms in examined compounds via correlation with the R(P) and S(P) diastereoisomers of guanosine 5'-O-(1-thiodiphosphate) (GDPalphaS).     

Affinity of dinucleotide cap analogues for human decapping scavenger (hDcpS)

Eukaryotic cells utilize scavenger decapping enzymes to degrade cap structure following 3'-5' mRNA decay. Human DcpS recently has been described as a highly specific hydrolase (a member of the HIT family) that catalyses the cleavage of m(7)GpppG and short capped oligoribonucleotides. We have demonstrated here that cap-1 (m(7)GpppGm) is a preferred substrate among several investigated dinucleotide cap analogues m(7)Gp(n)N (n = 3-5, N is a purine or pyrimidine base) and m(7)GMP is always one of the reaction product. Cap analogues containing pyrimidine base instead of guanine or diphosphate chain are resistant to hydrolysis catalyzed by human scavenger. Contrary to the other enzymes of HIT family, hDcpS activity is not stimulated by Mg(2+).     

Anticancer immunotherapy by CTLA-4 blockade: obligatory contribution of IL-2 receptors and negative prognostic impact of soluble CD25

The cytotoxic T lymphocyte antigen-4 (CTLA-4)-blocking antibody ipilimumab induces immune-mediated long-term control of metastatic melanoma in a fraction of patients. Although ipilimumab undoubtedly exerts its therapeutic effects via immunostimulation, thus far clinically useful, immunologically relevant biomarkers that predict treatment efficiency have been elusive. Here, we show that neutralization of IL-2 or blocking the α and β subunits of the IL-2 receptor (CD25 and CD122, respectively) abolished the antitumor effects and the accompanying improvement of the ratio of intratumoral T effector versus regulatory cells (Tregs), which were otherwise induced by CTLA-4 blockade in preclinical mouse models. CTLA-4 blockade led to the reduction of a suppressive CD4⁺ T cell subset expressing Lag3, ICOS, IL-10 and Egr2 with a concomitant rise in IL-2-producing effector cells that lost FoxP3 expression and accumulated in regressing tumors. While recombinant IL-2 improved the therapeutic efficacy of CTLA-4 blockade, the decoy IL-2 receptor α (IL-2Rα, sCD25) inhibited the anticancer effects of CTLA-4 blockade. In 262 metastatic melanoma patients receiving ipilimumab, baseline serum concentrations of sCD25 represented an independent indicator of overall survival, with high levels predicting resistance to therapy. Altogether, these results unravel a role for IL-2 and IL-2 receptors in the anticancer activity of CTLA-4 blockade. Importantly, our study provides the first immunologically relevant biomarker, namely elevated serum sCD25, that predicts resistance to CTLA-4 blockade in patients with melanoma.     

Recessive Osteogenesis Imperfecta Caused by Missense Mutations in SPARC

Secreted protein, acidic, cysteine-rich (SPARC) is a glycoprotein that binds to collagen type I and other proteins in the extracellular matrix. Using whole-exome sequencing to identify the molecular defect in two unrelated girls with severe bone fragility and a clinical diagnosis of osteogenesis imperfecta type IV, we identified two homozygous variants in SPARC (GenBank: {"type":"entrez-nucleotide","attrs":{"text":"NM_003118.3","term_id":"365777426","term_text":"NM_003118.3"}}NM_003118.3; c.497G>A [p.Arg166His] in individual 1; c.787G>A [p.Glu263Lys] in individual 2). Published modeling and site-directed mutagenesis studies had previously shown that the residues substituted by these mutations form an intramolecular salt bridge in SPARC and are essential for the binding of SPARC to collagen type I. The amount of SPARC secreted by skin fibroblasts was reduced in individual 1 but appeared normal in individual 2. The migration of collagen type I alpha chains produced by these fibroblasts was mildly delayed on SDS-PAGE gel, suggesting some overmodification of collagen during triple helical formation. Pulse-chase experiments showed that collagen type I secretion was mildly delayed in skin fibroblasts from both individuals. Analysis of an iliac bone sample from individual 2 showed that trabecular bone was hypermineralized on the material level. In conclusion, these observations show that homozygous mutations in SPARC can give rise to severe bone fragility in humans.     

RTTN Mutations Cause Primary Microcephaly and Primordial Dwarfism in Humans

Primary microcephaly is a developmental brain anomaly that results from defective proliferation of neuroprogenitors in the germinal periventricular zone. More than a dozen genes are known to be mutated in autosomal-recessive primary microcephaly in isolation or in association with a more generalized growth deficiency (microcephalic primordial dwarfism), but the genetic heterogeneity is probably more extensive. In a research protocol involving autozygome mapping and exome sequencing, we recruited a multiplex consanguineous family who is affected by severe microcephalic primordial dwarfism and tested negative on clinical exome sequencing. Two candidate autozygous intervals were identified, and the second round of exome sequencing revealed a single intronic variant therein (c.2885+8A>G [p.Ser963^∗] in RTTN exon 23). RT-PCR confirmed that this change creates a cryptic splice donor and thus causes retention of the intervening 7 bp of the intron and leads to premature truncation. On the basis of this finding, we reanalyzed the exome file of a second consanguineous family affected by a similar phenotype and identified another homozygous change in RTTN as the likely causal mutation. Combined linkage analysis of the two families confirmed that RTTN maps to the only significant linkage peak. Finally, through international collaboration, a Canadian multiplex family affected by microcephalic primordial dwarfism and biallelic mutation of RTTN was identified. Our results expand the phenotype of RTTN-related disorders, hitherto limited to polymicrogyria, to include microcephalic primordial dwarfism with a complex brain phenotype involving simplified gyration.     

Population genetic diversity of the clonal self‐incompatible herbaceous plant Linaria vulgaris along an urbanization gradient

How increasing urbanization affects biodiversity is one of the most understudied aspects of global change biology. It is, however, known that it may negatively affect plant population genetic diversity in numerous ways, for example through its negative effects on plant population size, between‐population connectivity, and reproductive success. Therefore, it is important to investigate to what extent different levels of urbanization result in these negative phenomena. Here we used microsatellite markers to investigate urbanization effects on the population genetic structure of 23 populations of the self‐incompatible, partially clonal herb Linaria vulgaris which were sampled across a gradient of urbanization. Clonal diversity as measured by the Pareto‐parameter varied between 1.11 and 2.97 and was negatively correlated to both the degree of urbanization and to population size. Urbanization and population size were not interrelated. The least clonally rich populations also experienced significantly reduced seed set. Irrespective of the degree of urbanization, L. vulgaris populations exhibited strong genetic differentiation (F_ST = 0.33) and there was no significant correlation between genetic and geographic distances, suggesting low gene flow among populations. In conclusion, we showed that urbanization negatively affected fitness of L. vulgaris populations through decreasing their clonal diversity and reproductive success, an effect that may be exacerbated by the low gene flow between populations. Although the effect was modest, the results could probably be extrapolated to bigger cities where it would be considerably more pronounced.