The differential hippocampal phosphoproteome of Apodemus sylvaticus paralleling spatial memory retrieval in the Barnes maze

Protein phosphorylation is a well-known and well-documented mechanism in memory processes. Although a large series of protein kinases involved in memory processes have been reported, information on phosphoproteins is limited. It was therefore the aim of the study to determine a partial and differential phosphoproteome along with the corresponding network in hippocampus of a wild caught mouse strain with excellent performance in several paradigms of spatial memory. Apodemus sylvaticus mice were trained in the Barnes maze, a non-invasive test system for spatial memory and untrained mice served as controls. Animals were sacrificed 6h following memory retrieval, hippocampi were taken, proteins extracted and in-solution digestion was carried out with subsequent iTRAQ double labelling. Phosphopeptides were enriched by a TiO2-based method and semi-quantified using two fragmentation principles on the LTQ-orbitrap Velos. In hippocampi of trained animals phosphopeptide levels representing signalling, neuronal, synaptosomal, cytoskeletal and metabolism proteins were at least twofold reduced or increased. Furthermore, a network revealing a link to pathways of ubiquitination, the androgen receptor, small GTPase Rab5 and MAPK signaling as well as synucleins was constructed. This work is relevant for interpretation of previous work and the design of future studies on protein phosphorylation in spatial memory.

Blood transfusions using 27 gauge PICC lines: a retrospective clinical study on safety and feasibility

BACKGROUND

Blood transfusions are required by most extremely low birth weight (ELBW) infants, but sometimes an adequate peripheral venous access cannot be achieved. Under these circumstances, we used 27 Gauge (G) peripherally inserted central catheter (PICC) lines that are routinely inserted on the second day of life. Due to their narrow lumen, hemolysis of transfused erythrocytes was a major concern. We therefore performed a retrospective study in ELBW infants to analyze the incidence, safety and feasibility of PRBC transfusions via 27 G PICC lines.

METHODS

ELBW infants admitted from 08/2011-07/2012 were screened for packed red blood cell (PRBC) transfusions. Those applied via 27 G PICC lines were identified. For analysis of transfusion safety (hemolysis), hemoglobin and potassium levels as well as cardiovascular variables (invasive mean arterial blood pressure and heart rate) were evaluated before and after transfusion. For analysis of transfusion feasibility, catheter removal after transfusion and the reason for removal were recorded.

RESULTS

A total of 648 transfusions were applied in 110 ELBW infants. 27 infants (24%) received no transfusion. In 12/83 (14.5%) infants who received PRBCs, transfusions were applied using a 27 G PICC line (38/648, 5.9%). Patients who received PRBCs via the PICC line were smaller at birth (582 g [range 380-752 g] vs. 710 g [430-972 g]; 23+6 [23+1-27+6] vs. 26+0 [23+1-31+4]) and required a higher number of PRBC transfusions (n=13 vs. n=5) overall. Transfusion analysis showed an appropriate increase of blood hemoglobin levels and stable potassium levels as well as cardiovascular parameters. 4/38 of PICC lines were removed within 24 h after transfusion, one due to occlusion (15 h after transfusion).

CONCLUSIONS

We conclude that PRBC transfusions via 27 G PICC lines were feasible and performed without signs of hemolysis in ELBW infants. Our findings may help clinicians in the management of ELBW infants requiring transfusions if a peripheral venous access is not achievable.

Safety of blood transfusions using 27 gauge neonatal PICC lines: an in vitro study on hemolysis

Blood transfusions are required by the majority of extremely premature infants. Packed red blood cells (PRBCs) are usually applied via simple peripheral cannulas. In situations where no peripheral venous access is achievable, 27 Gauge (G) neonatal PICC lines - that are ideally exclusively dedicated to application of parenteral nutrition - may represent a useful alternative access for PRBC transfusions. However, transfusion via small scaled catheters may damage PRBCs and lead to hemolysis. We here evaluate whether transfusion of irradiated PRBCs via 27 G PICC lines leads to hemolysis in vitro.Experimental transfusions of gamma-irradiated PRBCs were performed at increasing velocities (2.5, 3.7, 5 ml/h; full force manual push approximating 30 ml/h) via 27 G PICC lines of 20 and 30 cm length. Parameters of hemolysis (lactate dehydrogenase, potassium and free hemoglobin) were measured from the supernatants of transfused PRBCs and the percentage of hemolysis was calculated.Potassium and lactate dehydrogenase after transfusion at increasing velocities did not differ significantly from negative controls. Free hemoglobin levels showed a small but significant increase at the slowest transfusion speed (2.5 ml/h) using the 30 cm 27 G PICC line, with a relative hemolysis of only 0.13%. A manual push (approximating 30 ml/h) showed no significant changes of parameters from baseline.We conclude that transfusion of gamma-irradiated PRBCs using a 27 G neonatal PICC line does not cause clinically relevant hemolysis in vitro. Clinical studies are needed to confirm the feasibility and safety of the approach in vivo.

Safety Evaluation of Piperacillin/Tazobactam in Very Low Birth Weight Infants

An open, non-comparative study was designed to evaluate the safety and tolerance of parenteral piperacillin/tazobactam in very low birth weight infants. Twenty-seven patients were included for nosocomial sepsis with gram-negative bacteria (n = 4), nosocomial sepsis not responding to the empirical antibiotic regimen (n = 3), suspected necrotizing enterocolitis (n = 17), and infection after abdominal surgery for reasons other than necrotizing enterocolitis (n = 3). No clinical adverse events considered related to the study drug were noted, in particular, no cases of phlebitis, rash or stool changes. Several possibly related, mild and transitory abnormalities of laboratory parameters were observed. No long-lasting effect on the intestinal flora was detected. Seventeen patients (63%) were considered to have a favorable clinical response. This study demonstrates that piperacillin/tazobactam is a safe and well tolerated drug for preterm infants with bacterial infections, particularly those involving the gastrointestinal tract. Comparative clinical trials are warranted to further clarify the microbiological efficacy of piperacillin/tazobactam in this particular patient population.

The early prediction of neonatal morbidity and mortality in singleton small for gestational age infants with a birthweight < 1,500 g

OBJECTIVE

Identify factors for discrimination of "high" and "low risk" small for gestational age infants.

STUDY DESIGN

Singleton infants born small for gestational age with a birthweight  <1,500 g between 1999 and 2007 were included. Maternal, placental, and infant related factors were analyzed with regard to mortality and morbidity. Patients who died or suffered from complications were defined "high risk" as opposed to "low risk". Parameters associated with "high risk" were identified and an equation established to predict the minimal expected probability to die or suffer from neonatal morbidity.

RESULTS

Around 231 patients showed a mortality rate of 12.6 %, respiratory distress syndrome in 35.5 %, necrotizing enterocolitis in 8.2 % and neurological morbidities in 6.5 %. Of these, 58.9 % survived without complications. The factors for discrimination of "high" and "low risk" were Z-score of birth weight, gestational age, and pH.

CONCLUSION

We facilitate prognostication by classifying small for gestational age preterms into "low" and "high risk".

Successful implementation of a neonatal pain and sedation protocol at 2 NICUs

OBJECTIVE

To evaluate the implementation of a neonatal pain and sedation protocol at 2 ICUs.

METHODS

The intervention started with the evaluation of local practice, problems, and staff satisfaction. We then developed and implemented the Vienna Protocol for Neonatal Pain and Sedation. The protocol included well-defined strategies for both nonpharmacologic and pharmacologic interventions based on regular assessment of a translated version of the Neonatal Pain Agitation and Sedation Scale and titration of analgesic and sedative therapy according to aim scores. Health care staff was trained in the assessment by using a video-based tutorial and bedside teaching. In addition, we performed reevaluation, retraining, and random quality checks. Frequency and quality of assessments, pharmacologic therapy, duration of mechanical ventilation, and outcome were compared between baseline (12 months before implementation) and 12 months after implementation.

RESULTS

Cumulative median (interquartile range) opiate dose (baseline dose of 1.4 [0.5-5.9] mg/kg versus intervention group dose of 2.7 [0.4-57] mg/kg morphine equivalents; P = .002), pharmacologic interventions per episode of continuous sedation/analgesia (4 [2-10] vs 6 [2-13]; P = .005), and overall staff satisfaction (physicians: 31% vs 89%; P < .001; nurses: 17% vs 55%; P < .001) increased after implementation. Time on mechanical ventilation, length of stay at the ICU, and adverse outcomes were similar before and after implementation.

CONCLUSIONS

Implementation of a neonatal pain and sedation protocol at 2 ICUs resulted in an increase in opiate prescription, pharmacologic interventions, and staff satisfaction without affecting time on mechanical ventilation, length of intensive care stay, and adverse outcomes.

Homozygous SALL1 mutation causes a novel multiple congenital anomaly-mental retardation syndrome

OBJECTIVE

To delineate a novel autosomal recessive multiple congenital anomaly-mental retardation (MCA-MR) syndrome in 2 female siblings of a consanguineous pedigree and to identify the disease-causing mutation.

STUDY DESIGN

Both siblings were clinically characterized and homozygosity mapping and sequencing of candidate genes were applied. The contribution of nonsense-mediated messenger RNA (mRNA) decay to the expression of mutant mRNA in fibroblasts of a healthy carrier and a control was studied by pyrosequencing.

RESULTS

We identified the first homozygous SALL1 mutation, c.3160C > T (p.R1054*), in 2 female siblings presenting with multiple congenital anomalies, central nervous system defects, cortical blindness, and absence of psychomotor development (ie, a novel recognizable, autosomal recessive MCA-MR). The mutant SALL1 transcript partially undergoes nonsense-mediated mRNA decay and is present at 43% of the normal transcript level in the fibroblasts of a healthy carrier.

CONCLUSION

Previously heterozygous SALL1 mutations and deletions have been associated with dominantly inherited anal-renal-radial-ear developmental anomalies. We identified an allelic recessive SALL1-related MCA-MR. Our findings imply that quantity and quality of SALL1 transcript are important for SALL1 function and determine phenotype, and mode of inheritance, of allelic SALL1-related disorders. This novel MCA-MR emphasizes SALL1 function as critical for normal central nervous system development and warrants a detailed neurologic investigation in all individuals with SALL1 mutations.

Preterm neonates display altered plasmacytoid dendritic cell function and morphology

Bacterial and viral infections cause high rates of morbidity and mortality in premature newborns. In the setting of viral infection, pDCs play a key role as strong producers of IFN-α upon TLR9 activation. We analyzed pDC frequency, phenotype, morphology, and function in CB of preterm and term newborns in comparison with adults. Whereas all age groups show similar pDC numbers, BDCA-2, CD123, and TLR9 levels, the expression of BDCA-4 and capacity to produce IFN-α upon TLR9 challenge were decreased significantly in preterm neonates. Furthermore, we show by means of electron microscopy that pDCs from preterm newborns exhibit a distinct, "immature" morphology. Taken together, these findings suggest decreased functionality of pDCs in the premature newborn. The reduced capacity to produce IFN-α is likely to render such infants more susceptible to viral infections.

Evaluation of serological prenatal screening to detect Toxoplasma gondii infections in Austria

BACKGROUND

In Austria, a nationally mandated prenatal serological congenital toxoplasmosis screening program was introduced in 1974 in response to a high incidence of 7.8 per 1,000 infected infants. Maternal prenatal recognition of acute gestational infection and early treatment of infants with congenital infection are important because prenatal and accurate postnatal antibiotic therapy improves the outcomes of infected infants.

OBJECTIVE

To determine the impact of additional maternal and/or fetal cord blood serology at birth on improving current prenatal maternal screening in detecting congenital toxoplasmosis.

METHODS

In this prospective observational study, 5,545 consecutive women were included over a 19-month period. Routine prenatal maternal toxoplasmosis serology screening was performed along with additional cord blood serology screening at delivery. Fetal cord blood serology included Sabin-Feldman dye and IgM immunosorbent agglutination assay testing.

RESULTS

Based on the initial prenatal maternal screening serology results, there was evidence of a prior chronic infection manifest in 1,830 (33.0%) women and 3,708 (66.9%) were not infected. Seven (0.13%) were diagnosed with acute toxoplasma infection based on seroconversion. Of these, 4 manifested transmission, and 3 did not. Of the seven infected women, routine prenatal maternal screening identified acute infection in only 2 of the women, 1 of whom had an infected fetus with abnormal prenatal ultrasound. Fetal cord blood serology screening identified an additional 5 women, 3 with infected fetuses.

CONCLUSIONS

Identification of Toxoplasma gondii infection by prenatal maternal serological testing is significantly improved by the addition of maternal and/or fetal serological testing at birth.

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.

Perspectives on immunomodulation early in life

The immune system early in life is characterized by immature activation and function of immune cells and a preponderance of Th2 cytokines. Together with other factors such as genetics and epigenetics, these immature immune responses might prone newborns susceptible to severe infections as well as allergic diseases. Immunomodulation therapy may have potential as therapeutic strategy against those disorders and might have implication in early-life interventions in the future. In this review, we will focus on two immunomodulatory substance classes, Toll-like receptor (TLR) ligands and sphingolipids, which are the focus of extensive research to date. Both TLRs and sphingolipid receptors have a very distinct distribution pattern and function on immune cells. Therefore, they can potentially modulate and balance immune responses, which might be in particular beneficial for the immaturity of the immune response early in life.

Scopolamine administration modulates muscarinic, nicotinic and NMDA receptor systems

Studies on the effect of scopolamine on memory are abundant but so far only regulation of the muscarinic receptor (M1) has been reported. We hypothesized that levels of other cholinergic brain receptors as the nicotinic receptors and the N-methyl-D-aspartate (NMDA) receptor, known to be involved in memory formation, would be modified by scopolamine administration.

C57BL/6J mice were used for the experiments and divided into four groups. Two groups were given scopolamine 1 mg/kg i.p. (the first group was trained and the second group untrained) in the multiple T-maze (MTM), a paradigm for evaluation of spatial memory. Likewise, vehicle-treated mice were trained or untrained thus serving as controls. Hippocampal levels of M1, nicotinic receptor alpha 4 (Nic4) and 7 (Nic7) and subunit NR1containing complexes were determined by immunoblotting on blue native gel electrophoresis.

Vehicle-treated trained mice learned the task and showed memory retrieval on day 8, while scopolamine-treatment led to significant impairment of performance in the MTM. At the day of retrieval, hippocampal levels for M1, Nic7 and NR1 were higher in the scopolamine treated groups than in vehicle-treated groups.

The concerted action, i.e. the pattern of four brain receptor complexes regulated by the anticholinergic compound scopolamine, is shown. Insight into probable action mechanisms of scopolamine at the brain receptor complex level in the hippocampus is provided. Scopolamine treatment is a standard approach to test cognitive enhancers and other psychoactive compounds in pharmacological studies and therefore knowledge on mechanisms is of pivotal interest.

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 β-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.

Blocking mTORC1 activity by rapamycin leads to impairment of spatial memory retrieval but not acquisition in C57BL/6J mice

Although the involvement of the mTOR (mammalian target of rapamycin) system in memory processes has been reported, information on the effect of rapamycin on spatial learning and memory is limited. It was therefore the aim of the study to show the effect of parenteral rapamycin administration to C57BL/6J mice on performance in the multiple T-maze (MTM) and to determine hippocampal mTOR activity. Rapamycin-treated and -untreated/trained/probed mice are the main part of the experiment considering retrieval and acquisition or consolidation of spatial memory. Six hours following euthanasia hippocampi were extirpated and used for evaluation of mTOR activity as represented by hippocampal levels of S6 protein and its phosphorylated active form (phospho S6 protein, S240,244), a read out of mTOR complex 1 activity. Mice given i.p. rapamycin learned the task of the MTM but failed at the probe trial, showing absence of the phosphorylated active form of S6 protein, indicating inhibition of mTOR activity. Herein, impairing effects of rapamycin on retrieval but not on acquisition or consolidation of spatial memory are shown. Deficient memory retrieval was paralleled by inhibition of mTOR complex 1 activity. The current study extends knowledge on rapamycin in memory mechanisms and challenges work on deeper insights into the role of mTOR in different phases of memory formation and retrieval.

Hippocampal AMPA-type receptor complexes containing GluR3 and GluR4 are paralleling training in the Multiple T-Maze

Although it is well-known that AMPA receptors are involved in spatial learning and memory, published data on GluR3 and GluR4 are limited. Moreover, there is no information about GluR3 and GluR4 receptor complex levels in spatial memory training. It was therefore the aim of the study to determine the above-mentioned receptor levels following training in the Multiple T-Maze (MTM). Results from the MTM and hippocampal membrane proteins from C57BL/6J mice were taken from an own previous study and GluR3 and GluR4 receptor complexes were run on blue native gel electrophoresis followed by immunoblotting and quantification of bands. Subsequently, GluR3 and GluR4 were identified under denaturing conditions from two-dimensional gels by mass spectrometry (nano-LC-ESI-MS/MS). Hippocampal levels of GluR3 containing complexes (apparent molecular weight between 480 and 720) were decreased while GluR4 containing complexes (apparent molecular weight between 480 and 720) were increased. GluR4 complex levels in trained mice were correlating with latency and speed. Mass spectrometry unambiguously identified the two receptor subunits. The findings show that GluR3 and GluR4 may have different functions in the processes of spatial memory training in the MTM and indeed, different neurobiological functions of the two receptor subunits have been already reported. GluR3 and GluR4 receptor complex rather than subunit levels are paralleling training in the MTM and GluR4 complex levels were even linked to memory training, which may be of relevance for understanding molecular memory processes, interpretation of previous work or for design of future AMPA receptor studies.

In vitro comparison of noise levels produced by different CPAP generators

INTRODUCTION

Minimization of noise exposure is an important aim of modern neonatal intensive care medicine. Binasal continuous positive airway pressure (CPAP) generators are among the most important sources of continuous noise in neonatal wards. The aim of this study was to find out which CPAP generator creates the least noise.

METHOD

In an experimental setup, two jet CPAP generators (Infant Flow® generator and MediJet®) and two conventional CPAP generators (Bubble CPAP® and Baby Flow®) were compared. Noise production was measured in decibels in an A-weighted scale [dB(A)] in a closed incubator at 2 mm lateral distance from the end of the nasal prongs. Reproduction of constant airway pressure and air leak was achieved by closure of the nasal prongs with a type of adhesive tape that is semipermeable to air.

RESULTS

The noise levels produced by the four generators were significantly different (p < 0.001). Values measured at a continuous constant flow rate of 8 l/min averaged 83 dB(A) for the Infant Flow® generator with or without sound absorber, 72 dB(A) for the MediJet®, 62 dB(A) for the Bubble CPAP® and 55 dB(A) for the Baby Flow®.

CONCLUSION

Conventional CPAP generators work more quietly than the currently available jet CPAP generators.