First detection of heat shock protein 60 and 70 in the serum of early pregnant bitches.

Heat shock proteins (HSPs) belong to a group of cellular stress proteins. Heat shock protein 10 immunoregulates and promotes growth during early gestation in humans, while HSP70 is considered to regulate autophagy and apoptosis during pregnancy and parturition. Both HSPs are detectable in the serum and placentas of early pregnant women and considered to contribute to the establishment of pregnancy. Within this pilot study we aimed (1) to assess whether HSPs 10, 60 and 70 are measurable in the serum of healthy early pregnant and non-pregnant bitches, and (2) to explore whether measurable differences between groups indicate pregnancy. Blood was collected from 31 bitches on days 7, 14 and 21 after mating. At 21 days post mating, all bitches were examined for pregnancy by ultrasonography; 23 were pregnant, and the eight non-pregnant bitches served as controls. Pregnant bitches had normal parturitions and gave birth to healthy puppies. The serum concentrations of HSPs 10, 60 and 70 were measured by electrophoresis and western blot. Serum HSP10 was not detectable. Average serum HSP70 concentration was significantly (d7, P = 0.030; d14, P = 0.023; d21, P = 0.030) lower in pregnant animals at all days investigated, while serum HSP60 was significantly lower at day 21 of gestation (P = 0.024) when compared to the controls. HSP 60 and HSP70 concentrations correlated positively (d7, r = +0.386, P = 0.021; d14, r = 0.450, P = 0.008; d21, r = +0.472, P = 0.006). We conclude that in pregnant bitches, serum concentrations of HSP60 and HSP70 are significantly decreased between days 7 and 21 of gestation, in comparison to non-pregnant bitches in early dioestrus, raising the question about intrauterine functions during the peri-implantation period.

Neonatal screening for lysosomal storage disorders: feasibility and incidence from a nationwide study in Austria.

BACKGROUND: The interest in neonatal screening for lysosomal storage disorders has increased substantially because of newly developed enzyme replacement therapies, the need for early diagnosis, and technical advances. We tested for Gaucher's disease, Pompe's disease, Fabry's disease, and Niemann-Pick disease types A and B in an anonymous prospective nationwide screening study that included genetic mutation analysis to assess the practicality and appropriateness of including these disorders in neonatal screening panels. METHODS: Specimens from dried blood spots of 34,736 newborn babies were collected consecutively from January, 2010 to July, 2010, as part of the national routine Austrian newborn screening programme. Anonymised samples were analysed for enzyme activities of acid ß-glucocerebrosidase, α-galactosidase, α-glucosidase, and acid sphingomyelinase by electrospray ionisation tandem mass spectrometry. Genetic mutation analyses were done in samples with suspected enzyme deficiency. FINDINGS: All 34,736 samples were analysed successfully by the multiplex screening assay. Low enzyme activities were detected in 38 babies. Mutation analysis confirmed lysosomal storage disorders in 15 of them. The most frequent mutations were found for Fabry's disease (1 per 3859 births), followed by Pompe's disease (1 per 8684), and Gaucher's disease (1 per 17,368). The positive predictive values were 32% (95% CI 16-52), 80% (28-99), and 50% (7-93), respectively. Mutational analysis detected predominantly missense mutations associated with a late-onset phenotype. INTERPRETATION: The combined overall proportion of infants carrying a mutation for lysosomal storage disorders was higher than expected. Neonatal screening for lysosomal storage disorders is likely to raise challenges for primary health-care providers. Furthermore, the high frequency of late-onset mutations makes lysosomal storage disorders a broad health problem beyond childhood. FUNDING: Austrian Ministry of Health, Family, and Women.

Two site evaluation of the performance of a new generation point-of-care glucose meter for use in a neonatal intensive care unit.

BACKGROUND: Monitoring of blood glucose in neonatal intensive care unit (NICU) patients is important in maintaining normoglycaemia and reducing the risk of hypoglycaemia. Point-of-care testing (POCT) glucose meters provide short turnaround times but some have been reported to be affected by haematocrit interference and other biochemical or biological substances in their accuracy and performance. The aim of this study was to assess the performance of a new POCT glucose meter in a challenging preterm neonatal population. METHODS: The new Nova Biomedical StatStrip™ (Nova Biomedical) was tested on 159 heparinised whole blood samples from NICU patients obtained for blood gas analysis. Accuracy (bias) of the meter and analytical interferences were evaluated by comparing the results of the meter with the results of the blood gas analyser routinely used for glucose measurements in this NICU setting. RESULTS: The results of the StatStrip glucose meter correlated very well with the reference routine method across a wide glucose concentration range (13-389 mg/dL) and were not affected by the level of haematocrit, by sample pH or by medication. CONCLUSIONS: The StatStrip meter showed good clinical accuracy and performance for measuring and monitoring glucose levels in NICU patients, with special respect to preterm infants, and therefore can act as a perfect alternative to a blood gas analyser for measuring blood glucose in NICU patients.

Constant darkness induces IL-6-dependent depression-like behavior through the NF-κB signaling pathway.

Substantial experimental evidence indicates a major role for the circadian system in mood disorders. Additionally, proinflammatory cytokines have been proposed to be involved in the pathogenesis of depression. However, the molecular elements determining the functional interplay between these two systems in depression have not been described as yet. Here we investigate whether long-term light deprivation in the constant darkness (DD) paradigm affects depression-like behavior in mice and concomitantly modulates the levels of proinflammatory cytokines. We find that after 4 weeks of DD, mice display depression-like behavior, which is paralleled by reduced hippocampal cell proliferation. This chronobiologically induced depressive state is associated with elevated levels of plasma IL-6 (interleukin-6) and IL-6 and Il1-R1 (interleukin 1 receptor, type I) protein levels in the hippocampus and also alters hippocampal protein levels of the clock genes per2 and npas2. Using pharmacological blockers of the NF-κB pathway, we provide evidence that the effects of DD on depression-like behavior, on hippocampal cell proliferation, on altered expressional levels of brain and plasma IL-6, and on the modulation of clock gene expression are mediated through NF-κB signaling. Moreover, NF-κB activity is enhanced in hippocampal tissue of DD mice. Mice with a deletion of IL-6, one of the target genes of NF-κB, are resistant to DD-induced depression-like behavior, which suggests a pivotal role for this cytokine in the constant darkness mouse model of depression. We here first describe some of the molecular elements bridging chronobiological and inflammatory processes in the constant darkness mouse model of depression.

The predictive value of immature granulocyte count and immature myeloid information in the diagnosis of neonatal sepsis.

BACKGROUND: To determine the predictive value of the immature granulocyte count and the immature myeloid information in neonatal early onset sepsis we examined 133 blood samples of patients admitted to our neonatal intensive care unit. METHODS: Measurements were performed using the Sysmex XE-2100, an automated hematological analyzer. Patients were divided into two groups: 1) symptomatic neonates with diagnosis of early onset sepsis; and 2) controls including asymptomatic neonates who were admitted because of prematurity, low birth weight, or delayed postnatal transition. RESULTS: The number of immature granulocytes and the immature myeloid information were significantly elevated in neonates with early onset sepsis compared to controls (median 280/µL vs. 50/µL, p=0.049 and 639/µL vs. 89/µL, p<0.0001, respectively). CONCLUSIONS: Automated determinations of immature granulocytes and immature myeloid information seem to be useful adjunctive methods in the diagnosis of neonatal early onset sepsis.

Simplified newborn screening protocol for lysosomal storage disorders.

BACKGROUND: Interest in lysosomal storage disorders, a collection of more than 40 inherited metabolic disorders, has increased because of new therapy options such as enzyme replacement, stem cell transplantation, and substrate reduction therapy. We developed a high-throughput protocol that simplifies analytical challenges such as complex sample preparation and potential interference from excess residual substrate associated with previously reported assays. METHODS: After overnight incubation (16-20 h) of dried blood spots with a cassette of substrates and deuterated internal standards, we used a TLX-2 system to quantify 6 lysosomal enzyme activities for Fabry, Gaucher, Niemann-Pick A/B, Pompe, Krabbe, and mucopolysaccharidosis I disease. This multiplexed, multidimensional ultra-HPLC-tandem mass spectrometry assay included Cyclone P Turbo Flow and Hypersil Gold C8 columns. The method did not require offline sample preparation such as liquid-liquid and solid-phase extraction, or hazardous reagents such as ethyl acetate. RESULTS: Obviating the offline sample preparation steps led to substantial savings in analytical time (approximately 70%) and reagent costs (approximately 50%). In a pilot study, lysosomal enzyme activities of 8586 newborns were measured, including 51 positive controls, and the results demonstrated 100% diagnostic sensitivity and high specificity. The results for Krabbe disease were validated with parallel measurements by the New York State Screening Laboratory. CONCLUSIONS: Turboflow online sample cleanup and the use of an additional analytical column enabled the implementation of lysosomal storage disorder testing in a nationwide screening program while keeping the total analysis time to <2 min per sample.

In utero exposure to Ureaplasma spp. is associated with increased rate of bronchopulmonary dysplasia and intraventricular hemorrhage in preterm infants.

AIMS: We determined the association between short-term neonatal morbidities, such as bronchopulmonary dysplasia (BPD) and intraventricular hemorrhage (IVH), and Ureaplasma spp. in amniotic fluid, placental and amniotic membrane of preterm infants. METHODS: This study enrolled 257 patients who were born by cesarean section at <34 weeks' gestation. Patients were divided into two groups according to detection of Ureaplasma spp. by culture-based and/or polymerase chain reaction (PCR) techniques. RESULTS: Significant differences were observed between both groups for all IVH (P=0.032) and IVH grades III or IV (P=0.013), as wells as for BPD [odds ratio (OR) 5.46, 95% confidence interval (CI) 2.02-14.77], oxygen requirement at 28 days postnatal age (OR 1.93, 95% CI 1.00-3.70), and for death between 28 days and 36 postmenstrual weeks or BPD (OR 4.20, 95% CI 1.77-9.96). Ureaplasma spp. was a significant predictor (P<0.001) of BPD after correcting for birth weight (P=0.003) and positive pressure ventilation (P=0.001). CONCLUSIONS: In our study population Ureaplasma spp. was associated with BPD and IVH in preterm infants even after adjustment for multiple risk factors.

Effect of daily intake of yoghurt and bread enriched with biologically active substances on blood lipids and vitamin A in adolescents and young adults.

OBJECTIVE: The aim was to investigate whether the daily intake of special nutrients, enriched with supplements from natural origins, has any effect on blood parameters. DESIGN AND SUBJECTS: In this double-blind placebo-controlled clinical trial, 80 healthy subjects (mean age 26.3 years) were statistically assigned to two groups. Group I had to eat two special yoghurt and bread products a day. The other probands represented the control group (II). SETTING: Plasma concentrations of blood parameters were measured at the beginning and at the end of the study, and dietary intake was calculated. RESULTS: In group I, total cholesterol decreased. This was due to a significant drop of low-density lipoprotein-cholesterol from 106.0 to 99.0 mg/dl. A significant reduction of the apolipoprotein B and an increase of vitamin A in group I were also observed. CONCLUSION: Regular intake of specially fortified food influences parameters, especially lipids and lipoproteins.

Differential protein levels and post-translational modifications in spinal cord injury of the rat.

Although changes in protein expression in spinal cord injury (SCI) would be of pivotal interest, information so far is limited. It was therefore the aim of the study to determine protein levels and post-translational modifications in the early phase following SCI in the rat. SCI was induced in Sprague-Dawley rats and sham operated rats served as controls. A gel-based proteomic approach using two-dimensional gel electrophoresis followed by quantification with specific software and subsequent identification of differentially expressed proteins by nano-ESI-LC-MS/MS was applied. Proteins of several pathways and cascades were dysregulated in SCI: 14-3-3 epsilon protein, dynein light chain 1, and tubulin beta-5 chain showed higher levels in SCI, whereas adenylyl cyclase associated protein 1, dihydropyrimidinase-related protein 2, F-actin capping protein subunit beta, glyceraldehyde-3-phosphate dehydrogenase, stress-induced phosphoprotein 1 and transthyretin showed lower levels in the injured tissue. Post-translational modifications indicated free oxygen radical attack on proteins in SCI. The occurrence of stress is indicated by deranged stress-induced phosphoprotein 1 and signaling abnormalities are reflected by adenylyl cyclase-associated protein 1 and 14-3-3 epsilon protein. The findings propose the involvement of the corresponding cascades and challenge further work into aberrant signaling and oxidative stress in SCI, which may form the basis for experimental intervention for spinal cord trauma.

Evaluation of the Vitros ECiQ immunodiagnostic system for detection of anti-Toxoplasma immunoglobulin G and immunoglobulin M antibodies for confirmatory testing for acute Toxoplasma gondii infection in pregnant women.

Infection with Toxoplasma gondii is often asymptomatic and, when acquired during pregnancy, may lead to connatal toxoplasmosis in the offspring. The newly introduced Vitros anti-Toxoplasma immunoglobulin G (IgG) and IgM assays, designed for the Vitros ECiQ immunodiagnostic system, a fully automated system based on chemiluminescence, were evaluated as a screening method for the serological detection of acute and chronic Toxoplasma infections in the sera of 719 pregnant women. The combination of the Vitros IgG and IgM assays demonstrated a sensitivity and a specificity of 100% for the successful detection of all acute T. gondii infections by comparison with the Sabin-Feldman dye test as the reference test. The Vitros IgG assay parameter revealed a sensitivity of 95.0%, a specificity of 100.0%, a positive predictive value of 100.0%, a negative predictive value of 86.2%, and an overall agreement of 96.2% by comparison with the dye test. Comparison of the Vitros Toxoplasma IgM assay with the immunosorbent agglutination assay yielded values of 77.1%, 99.0%, 97.7%, 88.5%, and 91.1%, respectively. Subsequent receiver operating characteristic curve analysis for the accurate detection of Toxoplasma IgM in acute (n = 90) and chronic (n = 461) infections demonstrated high sensitivity (92.2%) and specificity (81.6%). The combination of a Toxoplasma-specific IgG assay with specific IgM antibody detection has improved the diagnosis of T. gondii infection by decreasing follow-up testing. Nonetheless, positive Toxoplasma IgM test results during pregnancy necessitate confirmatory testing by a reference laboratory to ensure fast and, above all, accurate test results.

Caffeine monitoring in infants: comparison of automated (VITROS 5, 1 FS) chemistry system versus HPLC analysis.

This is the first study comparing the caffeine testing by HPLC to the MicroTip Technology patented by Ortho-Clinical Diagnostics. For the determination of the precision for intra-run and day to day variances, control materials with concentration ranges between 2.3 microg/mL and 23.3 microg/mL were used. Test evaluation was done using plasma samples. The coefficient of variation for intra-run precision was calculated to range from 4.3% to 2.1%. The coefficients of variation for the day-to-day precision were between 4.9% and 2.3%. A coefficient of correlation of 0.99% was calculated for the comparison of the two methods. In the statistical analysis of the comparison of the methods. Differences between + 4.5% and - 0.92% could be found. The HPLC system must be ready for use at any time necessitating maintenance and increased costs. This, in addition to the low sample throughput for caffeine analysis and the findings of this study favour the use of an automated clinical chemistry system.

Evaluation of the VITROS 5,1 FS chemistry system in a large pediatric laboratory.

The VITROS 5,1 FS analytical system was evaluated. The measurement of the serum proteins and HDL cholesterol with the newly developed MicroTip technology was compared with other nephelometric and turbidimetric methods. The within-run imprecision for apolipoprotein A1, apolipoprotein B, complement 3, complement 4, transferrin, immunoglobulin A, immunoglobulin M, immunoglobulin G and HDL cholesterol showed coefficients of variation between 0.4% and 4.7%. The day-to-day imprecision showed coefficients of variation between 0.5% and 4.0%. The correlation with the comparative methods (nephelometric or turbidimetric) was good, with Pearson correlation coefficients of between 0.959 and 0.995. The comparison of apolipoprotein Al showed a slope of about 0.76. An explanation for the difference could not be found. The VITROS 5,1 FS analytical system is a reliable routine instrument which fits into a large pediatric laboratory of a university.

Behavioral testing upregulates pCaMKII, BDNF, PSD-95 and egr-1 in hippocampus of FVB/N mice.

Several protein cascades are proposed to be involved in the formation of synaptic plasticity and have been linked to neuronal information processing and storage. Although modified expression of specific proteins following behavioral testing has been shown, no systematic approach for their concomitant determination has been reported. We therefore determined hippocampal expression of signaling proteins, transcription factors and synaptosomal-associated proteins representing key elements of neuronal plasticity in mice following behavioral training. Male FVB/N mice, 12 weeks of age, were used for behavioral testing. After completion of tests mice were sacrificed and hippocampi were dissected. Levels of total and autophosphorylated (T286) alphacalcium-calmodulin dependent kinase II (CaMKII, pCaMKII), total and phosphorylated mitogen-activated protein kinase (MAPK, pMAPK), total and phosphorylated calcium-responsive element binding (creb, pcreb), early-growth response protein 1 (egr-1), brain derived neurotrophic factor (BDNF), tyrosine kinase receptor B (trk B), drebrin and postsynaptic density-95 (PSD-95) were quantified in hippocampi of behavior trained animals (n=7) and naïve caged controls (n=7). Expression of pCaMKII, BDNF, PSD-95 and egr-1 was significantly increased in the behavior-trained group. Expression of total CaMKII, total and pMAPK, total and pcreb, trk B and drebrin was comparable between groups. Detection of significantly increased pCaMKII, BDNF, PSD-95 and egr-1 induced by behavioral training at the protein level per se is intriguing and supports the proposed importance of these molecules for neuronal information storage.

Strain-dependent regulation of plasticity-related proteins in the mouse hippocampus.

Inbred mouse strains have different genetic backgrounds that can result in impairment of synaptic plasticity and memory. Strain-dependent performance in behavioral and cognitive tasks is well-documented. Hippocampal long-term potentiation (LTP), an activity-dependent enhancement of synaptic transmission that may underlie some forms of learning and memory has been shown to differ significantly between inbred mouse strains. However, an effect of strain on the expression of proteins, critically involved in synaptic plasticity, learning and memory has not been described yet. We have been addressing this question by determining expressional levels of a panel of proteins involved in neuronal information processing in hippocampus of five mouse strains by immunoblotting. Four inbred strains (FVB/N, C57Bl/6J, 129S2/Sv and Balb/c), commonly used for generating genetically modified mice and for conventional experiments in pharmacology and toxicology and one outbred strain (OF1) have been selected. A significant effect of strain was detected for total and phosphorylated calcium-calmodulin dependent kinase IIalpha (CaMKII, pCaMKII), phosphorylated mitogen-activated protein kinase (pMAPK), total and phosphorylated calcium-responsive element binding 1 (creb, pcreb), early-growth response protein 1 (egr 1), brain derived neurotrophic factor (BDNF), drebrin and postsynaptic density-95 (PSD-95). These results may indicate genetic determination of synaptic plasticity-related mechanisms relevant for the molecular events mediating hippocampal information processing and storage. Data presented herein highlight the importance of careful selection of the mouse strain for studies of synaptic plasticity.

Overexpression of activin beta(C) or activin beta(E) in the mouse liver inhibits regenerative deoxyribonucleic acid synthesis of hepatic cells.

Activins are dimeric growth factors composed of beta-subunits, four of which have been isolated so far. Whereas activin beta(A) and beta(B) are expressed in many tissues, the expression of activin beta(C) and beta(E) is confined to the liver. To date no biological role or activity has been assigned to activins formed from beta(C) or beta(E) subunits (activin C and E). Because activin A (beta(A)beta(A)), among its various functions in other tissues, appears to be a negative regulator of liver growth, we hypothesized a similar role for activin C and E. Using a nonviral gene transfer system we specifically delivered genes encoding activin beta(C), beta(E), or beta(A) to the mouse liver. The mRNA analysis and reporter gene coexpression both indicated a reproducible temporal and spatial transgene expression pattern. The effects of activin overexpression were studied in the context of a regenerative proliferation of hepatic cells, a result of the tissue damage associated with the hydrodynamics based gene transfer procedure. Activin beta(C), beta(E), or beta(A) expression, all temporarily inhibited regenerative DNA synthesis of hepatocytes and nonparenchymal cells, though to a varying degree. This first report of a biological activity of activin C and E supports an involvement in liver tissue homeostasis and further emphasizes the role of the growing activin family in liver physiology.

Cellular gene dose and kinetics of gene expression in mouse livers transfected by high-volume tail-vein injection of naked DNA.

Direct gene transfer to mammalian tissues has significant potential for biomedical research and gene therapy. Recently, the efficient transfer of naked plasmid DNA to the mouse liver by a rapid high-volume tail-vein injection was reported. We carried out a systematic analysis of the dose and time dependence of the expression of the Escherichia coli beta-galactosidase gene transferred by this technique. Surprisingly, the DNA concentration of the administered solution determined primarily the cellular gene dose and, hence, the expression of the transgene in individual hepatocytes, while the number of transfected cells was largely independent of the supplied plasmid mass. Transgene expression was transient: after a rapid onset and a peak at 8 h past injection, it gradually declined and was no longer detectable 4 weeks later. Although gene transfer was accompanied by tissue damage and subsequent regenerative proliferation, the decline in transgene expression was not due to increased hepatocyte turnover or to promoter downregulation, but instead cells apparently lost the plasmid DNA. Furthermore, we show that "nakedness" of the injected DNA is indeed a prerequisite for efficient transfer by the hydrodynamics-based procedure. Our data provide important clues for the successful use of this gene transfer technique, and may point directions for studies on the underlying mechanisms.

Antineutrophil cytoplasmic autoantibody-negative antiproteinase 3 syndrome presenting as vasculitis, endocarditis, polyneuropathy and Dupuytren's contracture.

Antiproteinase 3 antibodies (antiPR3) are assumed to be subtypes of antineutrophil cytoplasmic autoantibodies (ANCA), with a high specificity for active Wegener's granulomatosis and microscopic polyangiitis. Thus, antiPR3 positivity in ELISA, together with negativity in indirect immunofluorescence (IIF) is a rare finding. A 56-year-old man with Dupuytren's contracture and polyneuropathy was admitted for leukocytoclastic vasculitis. Echocardiography, performed because of fever and dyspnea, detected aortic valve endocarditis. Because of severe aortic insufficiency the valve was replaced. Blood cultures and bacteriologic investigations of the explanted valve were negative. AntiPR3 were elevated (123-163 U/ml; normal <6 U/ml), together with negativity in IIF. This case shows that antiPR3 elevation with negative ANCA may be associated with vasculitis, endocarditis, polyneuropathy and Dupuytren's contracture. A causal relationship between the clinical presentation and antiPR3 elevation is likely. In order not to miss such cases of vasculitis, combined screening by IIF and ELISA is recommended in selected cases.

Peritoneal transport kinetics of proteins in children on chronic peritoneal dialysis.

OBJECTIVE: This study describes a modified 4-hour peritoneal equilibration test (PET) for analyzing peritoneal transport characteristics of proteins with different molecular weights and predicting daily peritoneal protein losses in children on chronic peritoneal dialysis (PD). DESIGN: Cross-sectional study. SETTING: A single regional pediatric dialysis unit in a teaching hospital. PATIENTS: 9 stable pediatric dialysis patients; 4 were on continuous ambulatory PD, 5 were on continuous cycling PD. MAIN OUTCOME MEASURES: Serum and dialysate concentrations of IgG, albumin, beta2-microglobulin, and transferrin were determined during a PET. Changes in dialysate-to-plasma (D/P) ratios were determined hourly. Agreement between PET-derived and measured daily peritoneal protein losses was examined. RESULTS: The D/P ratio decreased with increased molecular radius (p < 0.0001). Many children had low plasma levels of IgG, albumin, and transferrin, but elevated levels of beta2-microglobulin. The D/P ratio increased linearly during the PET for all measured proteins, regardless of molecular weight. There was close correlation between 4-hour PET protein losses and 24-hour losses during routine PD. CONCLUSIONS: Proteins are lost through the peritoneum according to their size, demonstrating linear transport kinetics during a 4-hour PET. The PET-derived data predicted daily protein losses in children on chronic PD. This approach might help to eliminate inaccuracies due to incomplete dialysate collection.

Molecular detection of late-onset neonatal sepsis in premature infants using small blood volumes: proof-of-concept.

BACKGROUND: Conventional blood culture is still the gold standard for sepsis diagnosis but results are not immediately available and pathogens are only detected in approximately 25% of cases. New molecular assays for the detection of blood stream pathogens are promising diagnostic tools. OBJECTIVES: The aim of the study was to adapt and evaluate a multiplex PCR system using 100 µl blood. - METHODS: 46 blood specimens of very low birth weight infants (818 ± 242 g) with suspected sepsis were analyzed using the Roche SeptiFast MGRADE PCR with a modified DNA extraction protocol and software handling tool for decreased blood volume requirements. RESULTS: In the non-infected group, 5/21 infants had a positive PCR result with coagulase-negative staphylococci. All pathogens detected in the blood culture positive group (n = 15) were also detected by PCR. In addition, 4/6 patients had a positive PCR result in the clinical sepsis group (clinical and laboratory signs of sepsis but negative blood culture). Overall, the PCR was demonstrated to have a higher sensitivity (90.5%; 95%CI 68.2-98.3%) in comparison to blood culture (71.4%; 95%CI 47.7-87.8%) including clinical sepsis cases, even though it had a lower specificity (80.0%; 95%CI 58.7-92.4% versus 100.0%; 95%CI 83.4-100.0%). CONCLUSIONS: These first data demonstrate the usability and potential benefit of this multiplex PCR using a modified DNA extraction for the rapid detection of nosocomial sepsis in preterm infants in addition to blood culture.

DNA methylation pattern of CALCA in preterm neonates with bacterial sepsis as a putative epigenetic biomarker.

Diagnosis of bacterial sepsis in preterm neonates can be difficult when using serum markers that rely on physiological changes because these changes may not necessarily be the result of bacterial infections alone. This retrospective investigation explores the potential use of the DNA methylation pattern of CpG sites in the promoter region of the calcitonin-related polypeptide α (CALCA) gene as an epigenetic biomarker for bacterial sepsis in preterm newborns. Four novel changes in the DNA methylation of eight CpG sites were detected in this gene and are present only in neonates with bacterial sepsis: (1) partial methylation at -769 CpG in gram-negative or gram-positive early onset sepsis (EOS) and late onset sepsis (LOS) episodes; (2) demethylation of 8 CpGs in gram-negative EOS followed by LOS (ELS) and in gram-negative EOS; (3) demethylation of 7 CpGs in gram-positive ELS and gram-positive EOS; (4) -771 C:G>T:A; 5' de novo -778 CpG mutation on both alleles in EOS. These changes were not detected in birth weight and gestational age matched controls or in newborns with isolated infections. Our results indicate that the DNA methylation pattern of the promoter region of the CALCA gene varies in different types of bacterial preterm sepsis, thus suggesting a potential use as an epigenetic biomarker. A prospective confirmation of these results is essential.