Ythdf2 regulates cardiac remodeling through its mRNA target transcripts.

m6A mRNA methylation controls cardiomyocyte function and increased overall m6A levels are a stereotyping finding in heart failure independent of the underlying etiology. However, it is largely unknown how the information is read by m6A reader proteins in heart failure. Here we show that the m6A reader protein Ythdf2 controls cardiac function and identified a novel mechanism how reader proteins control gene expression and cardiac function. Deletion of Ythdf2 in cardiomyocytes in vivo leads to mild cardiac hypertrophy, reduced heart function, and increased fibrosis during pressure overload as well as during aging. Similarly, in vitro the knockdown of Ythdf2 results in cardiomyocyte growth and remodeling. Mechanistically, we identified the eucaryotic elongation factor 2 as post-transcriptionally regulated by Ythdf2 using cell type specific Ribo-seq data. Our study expands our understanding on the regulatory functions of m6A methylation in cardiomyocytes and how cardiac function is controlled by the m6A reader protein Ythdf2.

Estimating the association between antibiotic exposure and colonization with extended-spectrum ß-lactamase-producing Gram-negative bacteria using machine learning methods: a multicentre, prospective cohort study.

OBJECTIVES: The aim of the study was to measure the impact of antibiotic exposure on the acquisition of colonization with extended-spectrum ß-lactamase-producing Gram-negative bacteria (ESBL-GNB) accounting for individual- and group-level confounding using machine-learning methods. METHODS: Patients hospitalized between September 2010 and June 2013 at six medical and six surgical wards in Italy, Serbia and Romania were screened for ESBL-GNB at hospital admission, discharge, antibiotic start, and after 3, 7, 15 and 30 days. Primary outcomes were the incidence rate and predictive factors of new ESBL-GNB colonization. Random forest algorithm was used to rank antibiotics according to the risk of selection of ESBL-GNB colonization in patients not colonized before starting antibiotics. RESULTS: We screened 10 034 patients collecting 28 322 rectal swab samples. New ESBL-GNB colonization incidence with and without antibiotic treatment was 22/1000 and 9/1000 exposure-days, respectively. In the adjusted regression analyses, antibiotic exposure (hazard ratio (HR) 2.38; 95% CI 1.29-4.40), age 60-69 years (HR 1.19; 95% CI 1.05-1.34), and spring season (HR 1.25; 95% CI 1.14-1.38) were independently associated with new colonization. Monotherapy ranked higher als combination therapy in promoting ESBL-GNB colonization. Among monotherapy, cephalosporins ranked first followed by tetracycline (second), macrolide (fourth) and cotrimoxazole (seventh). Overall the ranking of cephalosporins was lower when used in combination. Among combinations not including cephalosporins, quinolones plus carbapenems ranked highest (eighth). Among sequential therapies, quinolones ranked highest (tenth) when prescribed within 30 days of therapy with cephalosporins. CONCLUSIONS: Impact of antibiotics on selecting ESBL-GNB at intestinal level varies if used in monotherapy or combination and according to previous antibiotic exposure. These finding should be explored in future clinical trials on antibiotic stewardship interventions. CLINICAL TRIAL REGISTRATION: NCT01208519.

Dynamics of the human gut phageome during antibiotic treatment.

Bacterial viruses contribute to the dynamics of the microbiome communities, as they are involved in the horizontal gene transfer. Previously we studied changes in the gut microbiome of the two healthy individuals over the course of a 6-days antibiotics treatment and subsequent 28 days recovery time (Willmann et al., 2015). Now, from the same samples, the virus-like particles were isolated and sequenced. As the phage sequences are currently poorly represented in reference databases, the reads had to be assembled, annotated and their abundance had to be evaluated via reads mapping. We analyzed and compared patterns of changes in abundance of the phage scaffolds and scaffolds with antibiotics resistant genes, in both phage and whole-genome metagenomic sets. We observed an increase in abundance of scaffolds carrying antibiotic-resistant genes in response to the treatment.

Identification of circular RNAs with host gene-independent expression in human model systems for cardiac differentiation and disease.

AIMS: Cardiovascular disease, one of the most common causes of death in western populations, is characterized by changes in RNA splicing and expression. Circular RNAs (circRNA) originate from back-splicing events, which link a downstream 5' splice site to an upstream 3' splice site. Several back-splicing junctions (BSJ) have been described in heart biopsies from human, rat and mouse hearts (Werfel et al., 2016; Jakobi et al., 2016 ). Here, we use human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) to identify circRNA and host gene dynamics in cardiac development and disease. In parallel, we explore candidate interactions of selected homologs in mouse and rat via RIP-seq experiments. METHODS AND RESULTS: Deep RNA sequencing of cardiomyocyte development and ß-adrenergic stimulation uncovered 4518 circRNAs. The set of circular RNA host genes is enriched for chromatin modifiers and GTPase activity regulators. RNA-seq and qRT-PCR data showed that circular RNA expression is highly dynamic in the hiPSC-CM model with 320 circRNAs showing significant expression changes. Intriguingly, 82 circRNAs are independently regulated to their host genes. We validated the same circRNA dynamics for circRNAs from ATXN10, CHD7, DNAJC6 and SLC8A1 in biopsy material from human dilated cardiomyopathy (DCM) and control patients. Finally, we could show that rodent homologs of circMYOD, circSLC8A1, circATXN7 and circPHF21A interact with either the ribosome or Argonaute2 protein complexes. CONCLUSION: CircRNAs are dynamically expressed in a hiPSC-CM model of cardiac development and stress response. Some circRNAs show similar, host-gene independent expression dynamics in patient samples and may interact with the ribosome and RISC complex. In summary, the hiPSC-CM model uncovered a new signature of potentially disease relevant circRNAs which may serve as novel therapeutic targets.

Association of five SNPs with human hair colour in the Polish population.

Twenty-two variants (single nucleotide polymorphisms - SNPs) of the genes involved in hair pigmentation (OCA2, HERC2, MC1R, SLC24A5, SLC45A2, TPCN2, TYR, TYRP1) were genotyped in a group of 186 Polish participants, representing a range of hair colours (45 red, 64 blond, 77 dark). A genotype-phenotype association analysis was performed. Using z-statistics we identified three variants highly associated with different hair colour categories (rs12913832:A>G in HERC2, rs1805007:T>C and rs1805008:C>T in MC1R). Two variants: rs1800401:C>T in OCA2 and rs16891982:C>G in SLC45A2 showed a high probability of a relation with hair colour, although that probability did not exceed the threshold of statistical significance after applying the Bonferroni correction. We created and validated mathematical logistic regression models in order to test the usefulness of the sets of polymorphisms for hair colour prediction in the Polish population. We subjected four models to stratified cross-validation. The first model consisted of three polymorphisms that proved to be important in the associative analysis. The second model included, apart from the mentioned polymorphisms, additionally rs16891982:C>G in SLC45A. The third model included, apart from the variants relevant in the associating analysis, rs1800401:C>T in OCA. The fourth model consisted of the set of polymorphisms from the first model supplemented with rs16891982:C>G in SLC45A and rs1800401:C>T in OCA. The validation of our models has shown that the inclusion of rs16891982:C>G in SLC45A and rs1800401:C>T in OCA increases the prediction of red hair in comparison with the algorithm including only rs12913832:A>G in HERC2, rs1805007:T>C and rs1805008:C>T in MC1R. The model consisting of all the five above-mentioned genetic variants has shown good prediction accuracies, expressed by the area under the curve (AUC) of the receiver operating characteristics: 0.84 for the red-haired, 0.82 for the dark-haired and 0.71 for the blond-haired. A genotype-phenotype association analysis brought results similar to those in other studies and confirmed the role of rs16891982:C>G, rs12913832:A>G, rs1805007:T>C and rs1805008:C>T in hair colour determination in the Polish population. Our study demonstrated for the first time the possibility of a share of the rs1800401:C>T SNP in the OCA2 gene in hair colour determination. Including this single nucleotide polymorphism in the actual hair colour predicting models would improve their predictive accuracy.

The impact of bone morphogenetic protein 4 (BMP4) on breast cancer metastasis in a mouse xenograft model.

Bone morphogenetic protein 4 (BMP4) is a key regulator of cell proliferation and differentiation. In breast cancer cells, BMP4 has been shown to reduce proliferation in vitro and interestingly, in some cases, also to induce migration and invasion. Here we investigated whether BMP4 influences breast cancer metastasis formation by using a xenograft mouse model. MDA-MB-231 breast cancer cells were injected intracardially into mice and metastasis formation was monitored using bioluminescence imaging. Mice treated with BMP4 developed metastases slightly earlier as compared to control animals but the overall number of metastases was similar in both groups (13 in the BMP4 group vs. 12 in controls). In BMP4-treated mice, bone metastases were more common (10 vs. 7) but adrenal gland metastases were less frequent (1 vs. 5) than in controls. Immunostaining revealed no differences in signaling activation, proliferation rate, blood vessel formation, EMT markers or the number of cancer-associated fibroblasts between the treatment groups. In conclusion, BMP4 caused a trend towards accelerated metastasis formation, especially in bone. More work is needed to uncover the long-term effects of BMP4 and the clinical relevance of these findings.

Insulin resistance in adolescents with Turner syndrome is comparable to obese peers, but the overall metabolic risk is lower due to unknown mechanism.

PURPOSE: An increased risk of insulin resistance, hypertension and liver dysfunction is related to obesity (Ob), but may be also present in normal-weight Turner syndrome (TS) patients. The aim of the study was to compare metabolic risk in adolescents with TS and Ob. METHODS: The study included 21 non-obese with TS (all receiving human recombinant growth hormone, 17/21 estrogen/estrogen-progesterone), and 21 age-matched Ob girls (mean age 13.9 years). Glucose and serum insulin levels were assessed fasting and in 120' of standard oral glucose tolerance test. Levels of triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, alanine aminotransferase (ALT), FGF19, FGF21 and FGF23 levels were measured fasting. RESULTS: Mean BMI SDS was significantly lower in TS patients (0.1 vs 4.8 SD, p < 0.001). The mean systolic and diastolic blood pressure was significantly lower in TS patients (102.6 vs 124.2 mmHg, p < 0.001 and 67.1 vs 76.5 mmHg, p = 0.02). There were no differences concerning mean fasting, and post-load glucose (4.5 vs 4.3, 5.1 vs 5.8 mmol/L), and insulin (14.97 vs 17.19 and 69.3 vs 98.78 µIU/mL) levels, HOMA-IR (3.02 vs 3.4), TC (4.05 vs 4.4 mmol/L), TG (1.25 vs 1.37 mmol/L), ALT (26.9 vs 28.3 IU/L), FGF19 (232.8 vs 182.7 pg/mL), and FGF23 (12.3 vs 17.5 pg/mL) levels. Mean LDL (2.05 vs 2.7 mmol/L, p = 0.003) and FGF21 (293.9 vs 514.7 pg/mL, p = 0.007) levels were significantly lower, and HDL (1.7 vs 1.2 mmol/L, p < 0.001) level higher in TS group. CONCLUSIONS: Insulin resistance in adolescents with TS on growth hormone treatment is comparable to Ob patients, but overall metabolic risk factors seem to be lower.

The role of adenosine A1 and A2A receptors in the caffeine effect on MDMA-induced DA and 5-HT release in the mouse striatum.

3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") popular as a designer drug is often used with caffeine to gain a stronger stimulant effect. MDMA induces 5-HT and DA release by interaction with monoamine transporters. Co-administration of caffeine and MDMA may aggravate MDMA-induced toxic effects on DA and 5-HT terminals. In the present study, we determined whether caffeine influences DA and 5-HT release induced by MDMA. We also tried to find out if adenosine A1 and A2A receptors play a role in the effect of caffeine by investigating the effect of the selective adenosine A1 and A2A receptor antagonists, DPCPX and KW 6002 on DA and 5-HT release induced by MDMA. Mice were treated with caffeine (10 mg/kg) and MDMA (20 or 40 mg/kg) alone or in combination. DA and 5-HT release in the mouse striatum was measured using in vivo microdialysis. Caffeine exacerbated the effect of MDMA on DA and 5-HT release. DPCPX or KW 6002 co-administered with MDMA had similar influence as caffeine, but KW 6002 was more potent than caffeine or DPCPX. To exclude the contribution of MAO inhibition by caffeine in the caffeine effect on MDMA-induced increase in DA and 5-HT, we also tested the effect of the nonxanthine adenosine receptor antagonist CGS 15943A lacking properties of MAO activity modification. Our findings indicate that adenosine A1 and A2A receptor blockade may account for the caffeine-induced exacerbation of the MDMA effect on DA and 5-HT release and may aggravate MDMA toxicity.

Inhibition of BMP signaling suppresses metastasis in mammary cancer.

Bone morphogenetic proteins (BMPs) are secreted cytokines/growth factors that have differing roles in cancer. BMPs are overexpressed in human breast cancers, but loss of BMP signaling in mammary carcinomas can accelerate metastasis. We show that human breast cancers display active BMP signaling, which is rarely downregulated or homozygously deleted. We hypothesized that systemic inhibition of BMP signaling in both the tumor and the surrounding microenvironment could prevent tumor progression and metastasis. To test this hypothesis, we used DMH1, a BMP antagonist, in MMTV.PyVmT expressing mice. Treatment with DMH1 reduced lung metastasis and the tumors were less proliferative and more apoptotic. In the surrounding tumor microenvironment, treatment with DMH1 altered fibroblasts, lymphatic vessels and macrophages to be less tumor promoting. These results indicate that inhibition of BMP signaling may successfully target both the tumor and the surrounding microenvironment to reduce tumor burden and metastasis.

Activity of N-acetyl-beta-hexosaminidase and its isoenzymes in serum and synovial fluid from patients with different arthropathies.

OBJECTIVE: To evaluate the activity of N-acetyl-Beta-hexosaminidase (HEX) and its isoenzymes in the serum and synovial fluid of healthy volunteers and patients with an injury to the anterior cruciate ligament and/or meniscus (ACL) osteoarthritis (OA), juvenile idiopathic arthritis (JIA) and rheumatoid arthritis (RA). METHODS: The activity of HEX and its isoenzymes was determined according to Zwierz et al. method. Protein content was determined by the biuret method. RESULTS: The specific activity of HEX and its isoenzymes in the serum of patients with JIA showed a tendency to increase in comparison to the reference group. The specific activity of total HEX in the serum of RA patients was significantly increased in comparison to control. Our results show, that specific activity of HEX in synovial fluid, in the reference group 4.2 +/- 0.21 microkat/kg protein (0.25 unit/mg protein), is similar to activity in normal temporomandibular joint fluid (0.3 unit/mg protein). Therefore, we included this group in our research. In patients with OA and ACL injuries, HEX and its isoenzymes showed a tendency to increase in the specific activity in synovial fluid. The specific activity of HEX and its isoenzymes in the synovial fluid of patients with RA and JIA was significantly elevated in comparison to the control and the remaining groups. CONCLUSION: In the synovial fluid of patients with JIA and RA, the specific activity of HEX and its isoenzymes significantly increased in comparison to control and patients with diseases of a non-inflammatory etiology (OA and ACL). In the synovial fluid of control and diseased groups, HEX constituted a higher percent of total proteins than in serum.

L-nucleosides containing modified nucleobases.

The synthesis of base modified L-nucleosides is described with pyrrolo[2,3-d]pyrimidines, pyrazolo[3,4-d]pyrimidines, benzimidazoles, and imidazo[1,2-a]-s-triazines as nucleobases. The conformation of the nucleosides is studied and the antiviral activity is evaluated.

The role of the therapeutic team in shaping eating habits and lifestyle in children with dietary calcium deficiency.

PURPOSE: Assessment of the effect of low-calcium diet on bone mineral content in children and adolescents. MATERIAL AND METHODS: The study involved 89 children (49 girls and 40 boys) aged 5-18 years, in whom diseases affecting bony metabolism had been excluded. Children with a history of dietary calcium content below 500 mg/day were recruited. The study group was divided according to age: group I, age 5-9 years (children before puberty); group II, age 9-15 years (early puberty); group III, 15-18 years (late puberty). Dual energy X-ray absorptiometry (DEXA) was used for densitometric measurements. Bone mineral density (BMD) was assessed in the whole skeleton (total BMD), in vertebrae L2-L4 (spine BMD) in g/cm2 and as Z-score. Concentrations of Ca, Ca2, P, activity of alkaline phosphatase (AP) and its bony isoenzyme were determined in the serum. RESULTS: Total bone mass below 5th percentile (according to the norm for age and gender) was found in 56.98% of the children involved in the study. A significant reduction was noted in the spine mineral mass in boys (p < 0.01) as compared to girls (0.731 +/- 0.17 g/cm2 and 0.835 +/- 0.19 g/cm2, respectively). The lowest mean Z-score (-1.850) was observed in group III as compared to group I (-1.194) (p < 0.01) and group II (-1.201) (p < 0.05). There were statistically significantly positive correlations between total and spine BMD and BMI. The correlation coefficient was r = 0.56 and r = 0.41 (p < 0.001), respectively. CONCLUSIONS: In the majority of the children (c. 60%), a reduction in bone mineral content was found. The lowest Z-score (-1.850) was revealed in the oldest children, which may disturb the process of reaching the optimum level of the peak bone mass.

Adamantylaminopyrimidines and -pyridines are potent inducers of tumor necrosis factor-alpha.

A series of (1-adamantyl)aminopyrimidine and -pyridine derivatives was prepared by adamantyl cation attack on amino heterocycles. The adamantylated compounds, particularly 2-(1-adamantyl)amino-6-methylpyridine, were found to be potent TNF-alpha inducers in murine melanoma cells transduced with gene for human TNF-alpha.

Synthesis, structure and tumour necrosis factor-alpha production-enhancing properties of novel adamantylamino heterocyclic derivatives.

The synthesis of several adamantylated aminoheterocycles is reported. The attack of the adamantyl cation formed from 1-adamantanol in refluxing trifluoroacetic acid or induced by microwave irradiation provides adamantylamino-derivatives of respective heterocycles. Adamantylated heterocycles enhance the induction of tumour necrosis factor alpha (TNF-alpha) in genetically modified murine melanoma cells transduced with the gene for human TNF-alpha. Of the studied collection of adamantylated compounds, the most biologically active are 2-adamantylamino-6-methylpyridine and 2-adamantylamino4-methylpyrimidine. The crystal structure of 2-adamantylamino-6-methylpyridine is reported.

Composition of phospholipid fatty acids in erythrocyte membranes of children with chronic juvenile arthritis: clinical and biochemical correlations.

Systemic diseases of connective tissue, including chronic juvenile arthritis are associated with a number of metabolic disorders such as e.g. lipid disturbances. The purpose of the present work was to analyse the composition of fatty acids in erythrocyte phospholipids of children with juvenile chronic arthritis and to determine a correlation between the composition of these acids and patients' clinical status. The study was conducted on 47 children with juvenile chronic arthritis (jca) and 29 healthy subjects. The following fractions of phospholipids were obtained with the help of thin-layer chromatography: phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidyloinositol, cardiolipin, sphingolipin. Fatty acids were analysed with the use of gas chromatograph (Hewlett-Packard 5890). Saturated fatty acids as well as mono- and polyunsaturated (n-3 and n-6) fatty acids were identified. The decrease in the percentage of linolenic acid, PUFA n-6 and PUFA n-3 was found in all the phospholipid fractions in children with jca when compared with control group. There was a concurrent increase in saturated fatty acids, mainly stearic and palmitic acids. The differences in the distribution of fatty acids in erythrocyte phospholipids were observed at early stage of the disease and they became more conspicuous as inflammatory process proceeded.

Overexpression of a kinase-deficient transforming growth factor-beta type II receptor in mouse mammary stroma results in increased epithelial branching.

Members of the transforming growth factor-beta (TGF-beta) superfamily signal through heteromeric type I and type II serine/threonine kinase receptors. Transgenic mice that overexpress a dominant-negative mutation of the TGF-beta type II receptor (DNIIR) under the control of a metallothionein-derived promoter (MT-DNIIR) were used to determine the role of endogenous TGF-betas in the developing mammary gland. The expression of the dominant-negative receptor was induced with zinc and was primarily localized to the stroma underlying the ductal epithelium in the mammary glands of virgin transgenic mice from two separate mouse lines. In MT-DNIIR virgin females treated with zinc, there was an increase in lateral branching of the ductal epithelium. We tested the hypothesis that expression of the dominant-negative receptor may alter expression of genes that are expressed in the stroma and regulated by TGF-betas, potentially resulting in the increased lateral branching seen in the MT-DNIIR mammary glands. The expression of hepatocyte growth factor mRNA was increased in mammary glands from transgenic animals relative to the wild-type controls, suggesting that this factor may play a role in TGF-beta-mediated regulation of lateral branching. Loss of responsiveness to TGF-betas in the mammary stroma resulted in increased branching in mammary epithelium, suggesting that TGF-betas play an important role in the stromal-epithelial interactions required for branching morphogenesis.

[Pseudohypoparathyroidism in a 14-year old girl]. / Rzekoma niedoczynnosc przytarczyc u 14-letniej dziewczynki.

The authors describe the case of a 14-year old girl with pseudohypoparathyroidism, who showed characteristic phenotypic features of Albright's hereditary osteodystrophy (short stature, round face, mild obesity, abnormal position of teeth, lack of canines, limb valgity) and biochemical disturbances--hypocalcemia, hyperphosphatemia. The nature of pseudohypoparathyroidism consists in a lack of response to the parathormone of effector organs, such as kidneys, bones, alimentary tract. The treatment of choice includes active metabolites of vitamin D3, calcium salts, phosphate-binding components. Pseudohypoparathyroidism is a rare disease. Worth noting is the fact that it can occur in a child with height deficiency.

Identification of STRAP, a novel WD domain protein in transforming growth factor-beta signaling.

Transforming growth factor-beta1 (TGF-beta1) is the prototype of a large family of proteins that regulate a variety of biological processes. The pleiotropic responses to TGF-beta are mediated via ligand-induced heteromeric complex formation by type I (TbetaR-I) and type II (TbetaR-II) serine-threonine kinase receptors. Several studies have shown that TbetaR-II acts as a primary receptor, binding TGF-beta and phosphorylating TbetaR-I, whose kinase activity then propagates the signals. Therefore, intracellular proteins that interact with type I receptors are likely to play important roles in TGF-beta signaling. We have identified a novel WD domain-containing protein, designated STRAP (serine-threonine kinase receptor-associated protein), which interacts with TbetaR-I in a yeast two-hybrid system. STRAP associates with both functional TbetaR-I and TbetaR-II in vivo. Overexpression of STRAP leads to inhibition of TGF-beta-mediated transcriptional activation. It also shows synergistic inhibition of TGF-beta signaling in concert with Smad7, but not with Smad6, as measured by TGF-beta-dependent transcriptional reporters. The existence of the STRAP gene from yeast to mammals indicates an evolutionarily conserved function in eukaryotes. The data suggest a potential role for STRAP in TGF-beta signal transduction.

Dominant-negative interference of the transforming growth factor beta type II receptor in mammary gland epithelium results in alveolar hyperplasia and differentiation in virgin mice.

Transforming growth factor (TGF)-beta1 and TGF-beta3 are normally expressed at high levels in the mammary gland during quiescence and at all stages of development, except lactation. Exogenously added TGF-beta1, -beta2, and -beta3 have been shown to regulate growth and differentiation of mammary epithelial cells in vitro and in vivo. TGF-betas signal through a heteromeric complex of type I and type II serine/threonine kinases. The type II receptor is necessary for ligand binding and growth suppression by TGF-betas. Deletions of the cytoplasmic domains of several kinase receptors known to function in multimeric complexes have been shown to act as dominant-negative mutations. To evaluate the role of endogenous TGF-betas in the growth and differentiation of the mammary gland in vivo, we have targeted expression of a truncated, kinase-defective TGF-beta type II receptor to mammary epithelial cells in transgenic mice using the mouse mammary tumor virus promoter/enhancer. Transgene expression was localized to the epithelial cells of terminal ducts and alveolar buds. At approximately 20 weeks of age, virgin female transgenic mice demonstrated varying degrees of mammary epithelial hyperplasia. Mammary glands from transgenic, virgin animals exhibited alveolar development and expression of the milk protein, beta-casein. The data suggest that impaired responsiveness in the epithelium to endogenous TGF-betas results in inappropriate alveolar development and differentiation in the mammary gland. We conclude that endogenous TGF-betas signal to the epithelium to maintain quiescence in the mammary glands of virgin animals.