Context- and Prosody-Driven ERP Markers for Dialog Focus Perception in Children.

The development of language proficiency extends late into childhood and includes not only producing or comprehending sounds, words and sentences, but likewise larger utterances spanning beyond sentence borders like dialogs. Dialogs consist of information units whose value constantly varies within a verbal exchange. While information is focused when introduced for the first time or corrected in order to alter the knowledge state of communication partners, the same information turns into shared knowledge during the further course of a verbal exchange. In many languages, prosodic means are used by speakers to highlight the informational value of information foci. Our study investigated the developmental pattern of event-related potentials (ERPs) in three age groups (12, 8 and 5 years) when perceiving two information focus types (news and corrections) embedded in short question-answer dialogs. The information foci contained in the answer sentences were either adequately marked by prosodic means or not. In so doing, we questioned to what extent children depend on prosodic means to recognize information foci or whether contextual means as provided by dialog questions are sufficient to guide focus processing.Only 12-year-olds yield prosody-independent ERPs when encountering new and corrective information foci, resembling previous findings in adults. Focus processing in the 8-year-olds relied upon prosodic highlighting, and differing ERP responses as a function of focus type were observed. In the 5-year-olds, merely prosody-driven ERP responses were apparent, but no distinctive ERP indicating information focus recognition. Our findings reveal substantial alterations in information focus perception throughout childhood that are likely related to long-lasting maturational changes during brain development.

Feasibility of non-invasive pressure support ventilation in infants with respiratory failure after extubation: a pilot study.

OBJECTIVE: To evaluate the feasibility and effects of non-invasive pressure support ventilation (NIV) on the breathing pattern in infants developing respiratory failure after extubation. DESIGN: Prospective pilot clinical study; each patient served as their own control. SETTING: A nine-bed paediatric intensive care unit of a tertiary university hospital. PATIENTS: Six patients (median age 5 months, range 0.5-7 months; median weight 4.2 kg, range 3.8-5.1 kg) who developed respiratory failure after extubation. INTERVENTIONS: After a period of spontaneous breathing (SB), children who developed respiratory failure were treated with NIV. MEASUREMENTS AND RESULTS: Measurements included clinical dyspnoea score (DS), blood gases and oesophageal pressure recordings, which were analysed for respiratory rate (RR), oesophageal inspiratory pressure swing (dPes) and oesophageal pressure-time product (PTPes). All data were collected during both periods (SB and NIV). When comparing NIV with SB, DS was reduced by 44% (P < 0.001), RR by 32% (P < 0.001), dPes by 45% (P < 0.01) and PTPes by 57% (P < 0.001). A non-significant trend for decrease in PaCO(2) was observed. CONCLUSION: In these infants, non-invasive pressure support ventilation with turbine flow generator induced a reduction of breathing frequency, dPes and PTPes, indicating reduced load of the inspiratory muscles. NIV can be used with some benefits in infants with respiratory failure after extubation.

Urinary D-lactate excretion in infants receiving Lactobacillus johnsonii with formula.

BACKGROUND/AIMS: Supplementation with certain probiotics can improve gut microbial flora and immune function but should not have adverse effects. This study aimed to assess the risk of D-lactate accumulation and subsequent metabolic acidosis in infants fed on formula containing Lactobacillus johnsonii (La1). METHODS: In the framework of a double-blind, randomized controlled trial enrolling 71 infants aged 4-5 months, morning urine samples were collected before and 4 weeks after being fed formulas with or without La1 (1 x 10(8)/g powder) or being breastfed. Urinary D- and L-lactate concentrations were assayed by enzymatic, fluorimetric methods and excretion was normalized per mol creatinine. RESULTS: At baseline, no significant differences in urinary D-/L-lactate excretion among the formula-fed and breastfed groups were found. After 4 weeks, D-lactate excretion did not differ between the two formula groups, but was higher in both formula groups than in breastfed infants. In all infants receiving La1, urinary D-lactate concentrations remained within the concentration ranges of age-matched healthy infants which had been determined in an earlier study using the same analytical method. Urinary L-lactate also did not vary over time or among groups. CONCLUSIONS: Supplementation of La1 to formula did not affect urinary lactate excretion and there is no evidence of an increased risk of lactic acidosis.

Bilateral Sequential NAION: A Comparison of Visual Outcomes in Fellow Eyes Using Quantitative Analysis of Goldmann Visual Fields

Purpose: Previous studies of the visual outcome in bilateral non-arteritic anterior ischemic optic neuropathy (NAION) have yielded conflicting results, specifically regarding congruity between fellow eyes. Prior studies have used measures of acuity and computerized perimetry but none has compared Goldmann visual field outcomes between fellow eyes. In order to better define the concordance of visual loss in this condition, we reviewed our cases of bilateral sequential NAION, including measures of visual acuity, pupillary function and both pattern and severity of visual field loss.Methods: We performed a retrospective chart review of 102 patients with a diagnosis of bilateral sequential NAION. Of the 102 patients, 86 were included in the study for analysis of final visual outcome between the affected eyes. Visual function was assessed using visual acuity, Goldmann visual fields, color vision and RAPD. A quantitative total visual field score and score per quadrant was analyzed for each eye using the numerical Goldmann visual field scoring method previously described by Esterman and colleagues. Based upon these scores, we calculated the total deviation and pattern deviation between fellow eyes and between eyes of different patients. Statistical significance was determined using nonparametric tests.Results: A statistically significant correlation was found between fellow eyes for multiple parameters, including logMAR visual acuity (P = 0.0101), global visual field (P = 0.0001), superior visual field (P = 0.0001), and inferior visual field (P = 0.0001). In addition, the mean deviation of both total (P = 0.0000000007) and pattern (P = 0.000000004) deviation analyses was significantly less between fellow eyes ("intra"-eyes) than between eyes of different patients ("inter"-eyes).Conclusions: Visual function between fellow eyes showed a fair to moderate correlation that was statistically significant. The pattern of vision loss was also more similar in fellow eyes than between eyes of different patients. These results may help allow better prediction of visual outcome for the second eye in patients with NAION. These findings may also be useful for evaluating efficacy of therapeutic interventions.

Surgical treatment of temporoparietooccipital cortical dysplasia in infants: report of two cases.

PURPOSE: Extensive multilobar cortical dysplasia in infants commonly is first seen with catastrophic epilepsy and poses a therapeutic challenge with respect to control of epilepsy, brain development, and psychosocial outcome. Experience with surgical treatment of these lesions is limited, often not very encouraging, and holds a higher operative risk when compared with that in older children and adults. METHODS: Two infants were evaluated for surgical control of catastrophic epilepsy present since birth, along with a significant psychomotor developmental delay. Magnetic resonance imaging showed multilobar cortical dysplasia (temporoparietooccipital) with a good electroclinical correlation. They were treated with a temporal lobectomy and posterior (parietooccipital) disconnection. RESULTS: Both infants had excellent postoperative recovery and at follow-up (1.5 and 3.5 years) evaluation had total control of seizures with a definite "catch up" in their development, both motor and cognitive. No long-term complications have been detected to date. CONCLUSIONS: The incorporation of disconnective techniques in the surgery for extensive multilobar cortical dysplasia in infants has made it possible to achieve excellent seizure results by maximizing the extent of surgical treatment to include the entire epileptogenic zone. These techniques decrease perioperative morbidity, and we believe would decrease the potential for the development of long-term complications associated with large brain excisions.

Factors affecting visual analysis in single-case designs

Visual inspection remains the most frequently applied method for detecting treatment effects in single-case designs. The advantages and limitations of visual inference are here discussed in relation to other procedures for assessing intervention effectiveness. The first part of the paper reviews previous research on visual analysis, paying special attention to the validation of visual analysts" decisions, inter-judge agreement, and false alarm and omission rates. The most relevant factors affecting visual inspection (i.e., effect size, autocorrelation, data variability, and analysts" expertise) are highlighted and incorporated into an empirical simulation study with the aim of providing further evidence about the reliability of visual analysis. Our results concur with previous studies that have reported the relationship between serial dependence and increased Type I rates. Participants with greater experience appeared to be more conservative and used more consistent criteria when assessing graphed data. Nonetheless, the decisions made by both professionals and students did not match sufficiently the simulated data features, and we also found low intra-judge agreement, thus suggesting that visual inspection should be complemented by other methods when assessing treatment effectiveness.

Development of projections from auditory to visual areas in the cat.

In newborn kittens, cortical auditory areas (including AI and AII) send transitory projections to ipsi- and contralateral visual areas 17 and 18. These projections originate mainly from neurons in supragranular layers but also from a few in infragranular layers (Innocenti and Clarke: Dev. Brain Res. 14:143-148, '84; Clarke and Innocenti: J. Comp. Neurol. 251:1-22, '86). The postnatal development of these projections was studied with injections of anterograde tracers (wheat germ agglutinin-horseradish peroxidase [WGA-HRP]) in AI and AII and of retrograde tracers (WGA-HRP, fast blue, diamidino yellow, rhodamine-labeled latex beads) in areas 17 and 18. It was found that the projections are nearly completely eliminated in development, this, by the end of the first postnatal month. Until then, most of the transitory axons seem to remain confined to the white matter and the depth of layer VI; a few enter it further but do not appear to form terminal arbors. As for other transitory cortical projections the disappearance of the transitory axons seems not to involve death of their neurons of origin. In kittens older than 1 month and in normal adult cats, retrograde tracer injections restricted to, or including, areas 17 and 18 label only a few neurons in areas AI and AII. Unlike the situation in the kitten, nearly all of these are restricted to layers V and VI. A similar distribution of neurons projecting from auditory to visual areas is found in adult cats bilaterally enucleated at birth, which suggests that the postnatal elimination of the auditory-to-visual projection is independent of visual experience and more generally of information coming from the retina.

Visual cortex in Alzheimer's disease: occurrence of neuronal death and glial proliferation, and correlation with pathological hallmarks.

Visual areas 17 and 18 were studied with morphometric methods for numbers of neurons, glia, senile plaques (SP), and neurofibrillary tangles (NFT) in 13 cases of Alzheimer's disease (AD) as compared to 11 controls. In AD cases, the mean neuronal density was significantly decreased by about 30% in both areas 17 and 18, while the glial density was increased significantly only in area 17. The volume of area 17 was unchanged in AD cases but its total number of neurons was decreased by 33% and its total number of glia increased by 45% compared to controls. In AD the number of SP was similar in areas 17 and 18, while that of NFT was significantly higher in area 18. The number of neurons with NFT was only 2% in area 17 and about 10% in area 18. The discrepancy between the loss of neurons and the amount of NFT suggests that neuronal loss can occur without passing through NFT degeneration. The deposition of SP was correlated with glial proliferation, but not with neuronal loss or neurofibrillary degeneration.

Organ volume measurements: comparison between MRI and autopsy findings in infants following sudden unexpected death.

OBJECTIVE: To assess the accuracy of a semiautomated 3D volume reconstruction method for organ volume measurement by postmortem MRI. METHODS: This prospective study was approved by the institutional review board and the infants' parents gave their consent. Postmortem MRI was performed in 16 infants (1 month to 1 year of age) at 1.5 T within 48 h of their sudden death. Virtual organ volumes were estimated using the Myrian software. Real volumes were recorded at autopsy by water displacement. The agreement between virtual and real volumes was quantified following the Bland and Altman's method. RESULTS: There was a good agreement between virtual and real volumes for brain (mean difference: -0.03% (-13.6 to +7.1)), liver (+8.3% (-9.6 to +26.2)) and lungs (+5.5% (-26.6 to +37.6)). For kidneys, spleen and thymus, the MRI/autopsy volume ratio was close to 1 (kidney: 0.87±0.1; spleen: 0.99±0.17; thymus: 0.94±0.25), but with a less good agreement. For heart, the MRI/real volume ratio was 1.29±0.76, possibly due to the presence of residual blood within the heart. The virtual volumes of adrenal glands were significantly underestimated (p=0.04), possibly due to their very small size during the first year of life. The percentage of interobserver and intraobserver variation was lower or equal to 10%, but for thymus (15.9% and 12.6%, respectively) and adrenal glands (69% and 25.9%). CONCLUSIONS: Virtual volumetry may provide significant information concerning the macroscopic features of the main organs and help pathologists in sampling organs that are more likely to yield histological findings.

Pneumocystis-carinii-Pneumonie bei Säuglingen mit vertikaler HIV-Infektion in der Schweiz [Pneumocystis carinii pneumonia in infants with vertically acquired HIV infection in Switzerland]

OBJECTIVE: Review of incidence, clinical picture, therapy, and outcome of Pneumocystis carinii pneumonia (PCP) in infants with vertically-acquired HIV infection in Switzerland. METHODS: Inquiry among members of the Swiss Pediatrics AIDS Group, review of the data base of the Swiss Neonatal HIV Study and retrospective analysis of the charts from infants with PCP. RESULTS: Since 1986 PCP has been diagnosed in 10 out of 107 infants with vertically-acquired HIV infection. PCP occurred in 7 infants at the age of 3-6 months and in 3 at the age of 9-11 months. 4 infants showed symptoms related to HIV infection before developing PCP. Before the development of PCP, infection with HIV had been ascertained in 6 infants. In 2 the diagnosis was still unclear and in the 2 remaining the risk of HIV infection was not known. None of the infants was on primary prophylaxis against PCP. Signs and symptoms of PCP included cough and tachypnea (100%) as well as high fever up to 40 degrees C (90%). Transcutaneous oxygen saturation was 70-95%. Chest X-rays revealed interstitial infiltrates in 6 infants, localized infiltrates in 2 and interstitial as well as localized infiltrates in 2. The CD4+ cell count was, with one exception, < 1500/microliters, i.e. below the normal value for age. Side effects of high dose cotrimoxazole were noted in 6 patients. 5 infants required intubation and mechanical ventilation. 4 infants died due to PCP, including 3 of those who required intubation and mechanical ventilation. CONCLUSIONS: PCP in infants with vertically-acquired HIV infection preferentially occurs at the age of 3 to 6 months and is often lethal, especially in patients requiring intubation. Evaluation for HIV infection should be done as early as possible in order to introduce primary PCP prophylaxis in infants at risk for this opportunistic infection.

Reduction in the use of diagnostic tests in infants with risk factors for early-onset neonatal sepsis does not delay antibiotic treatment.

Despite a low positive predictive value, diagnostic tests such as complete blood count (CBC) and C-reactive protein (CRP) are commonly used to evaluate whether infants with risk factors for early-onset neonatal sepsis (EOS) should be treated with antibiotics. We investigated the impact of implementing a protocol aiming at reducing the number of diagnostic tests in infants with risk factors for EOS in order to compare the diagnostic performance of repeated clinical examination with CBC and CRP measurement. The primary outcome was the time between birth and the first dose of antibiotics in infants treated for suspected EOS. Among the 11,503 infants born at ≥35 weeks during the study period, 222 were treated with antibiotics for suspected EOS. The proportion of infants receiving antibiotics for suspected EOS was 2.1% and 1.7% before and after the change of protocol (p = 0.09). Reduction of diagnostic tests was associated with earlier antibiotic treatment in infants treated for suspected EOS (hazard ratio 1.58; 95% confidence interval [CI] 1.20-2.07; p <0.001), and in infants with neonatal infection (hazard ratio 2.20; 95% CI 1.19-4.06; p = 0.01). There was no difference in the duration of hospital stay nor in the proportion of infants requiring respiratory or cardiovascular support before and after the change of protocol. Reduction of diagnostic tests such as CBC and CRP does not delay initiation of antibiotic treatment in infants with suspected EOS. The importance of clinical examination in infants with risk factors for EOS should be emphasised.

Patient-ventilator asynchrony during noninvasive pressure support ventilation and neurally adjusted ventilatory assist in infants and children.

OBJECTIVES: To document the prevalence of asynchrony events during noninvasive ventilation in pressure support in infants and in children and to compare the results with neurally adjusted ventilatory assist. DESIGN: Prospective randomized cross-over study in children undergoing noninvasive ventilation. SETTING: The study was performed in a PICU. PATIENTS: From 4 weeks to 5 years. INTERVENTIONS: Two consecutive ventilation periods (pressure support and neurally adjusted ventilatory assist) were applied in random order. During pressure support (PS), three levels of expiratory trigger (ETS) setting were compared: initial ETS (PSinit), and ETS value decreased and increased by 15%. Of the three sessions, the period allowing for the lowest number of asynchrony events was defined as PSbest. Neurally adjusted ventilator assist level was adjusted to match the maximum airway pressure during PSinit. Positive end-expiratory pressure was the same during pressure support and neurally adjusted ventilator assist. Asynchrony events, trigger delay, and cycling-off delay were quantified for each period. RESULTS: Six infants and children were studied. Trigger delay was lower with neurally adjusted ventilator assist versus PSinit and PSbest (61 ms [56-79] vs 149 ms [134-180] and 146 ms [101-162]; p = 0.001 and 0.02, respectively). Inspiratory time in excess showed a trend to be shorter during pressure support versus neurally adjusted ventilator assist. Main asynchrony events during PSinit were autotriggering (4.8/min [1.7-12]), ineffective efforts (9.9/min [1.7-18]), and premature cycling (6.3/min [3.2-18.7]). Premature cycling (3.4/min [1.1-7.7]) was less frequent during PSbest versus PSinit (p = 0.059). The asynchrony index was significantly lower during PSbest versus PSinit (40% [28-65] vs 65.5% [42-76], p < 0.001). With neurally adjusted ventilator assist, all types of asynchronies except double triggering were reduced. The asynchrony index was lower with neurally adjusted ventilator assist (2.3% [0.7-5] vs PSinit and PSbest, p < 0.05 for both comparisons). CONCLUSION: Asynchrony events are frequent during noninvasive ventilation with pressure support in infants and in children despite adjusting the cycling-off criterion. Compared with pressure support, neurally adjusted ventilator assist allows improving patient-ventilator synchrony by reducing trigger delay and the number of asynchrony events. Further studies should determine the clinical impact of these findings.