TFG binds LC3C to regulate ULK1 localization and autophagosome formation.

The early secretory pathway and autophagy are two essential and evolutionarily conserved endomembrane processes that are finely interlinked. Although growing evidence suggests that intracellular trafficking is important for autophagosome biogenesis, the molecular regulatory network involved is still not fully defined. In this study, we demonstrate a crucial effect of the COPII vesicle-related protein TFG (Trk-fused gene) on ULK1 puncta number and localization during autophagy induction. This, in turn, affects formation of the isolation membrane, as well as the correct dynamics of association between LC3B and early ATG proteins, leading to the proper formation of both omegasomes and autophagosomes. Consistently, fibroblasts derived from a hereditary spastic paraparesis (HSP) patient carrying mutated TFG (R106C) show defects in both autophagy and ULK1 puncta accumulation. In addition, we demonstrate that TFG activity in autophagy depends on its interaction with the ATG8 protein LC3C through a canonical LIR motif, thereby favouring LC3C-ULK1 binding. Altogether, our results uncover a link between TFG and autophagy and identify TFG as a molecular scaffold linking the early secretion pathway to autophagy.

Balancing emotional processing with ongoing cognitive activity: the effects of task modality on intrusions and rumination.

In the present paper we aimed to show that competition for resources between post-emotional processes and the execution of a cognitive task will result in two possible effects: (1) an impairment of the cognitive task in the short run and (2) an elongation of intrusions and rumination in the long run. The outcome of this competition is influenced by the interaction of the modality (verbal vs. visuospatial) of cognitive tasks run in the aftermath of an emotional experience and the nature (verbal vs. visuospatial) of the same experience. Non-clinical participants were given a working memory task (OSPAN vs. an analog Visual task) before and after the presentation of negative vs. neutral material (a novel excerpt in Experiment 1 and a video clip in Experiment 2). Intrusions and rumination were measured after a 24-h delay. Rumination was also assessed immediately after the experimental induction. Results showed that exposure to verbal negative material impaired verbal performance (Experiment 1); by contrast, exposure to visual negative material impaired both verbal and visuospatial performance (Experiment 2). Intrusions were only affected by the emotional valence of the original experience, while performing a visuospatial task resulted in enhanced rumination only after exposure to verbal emotional material. The findings of both experiments suggest that emotional processing spreads over time in balance with ongoing cognitive activities, and, in such a balance, the visuospatial processing mode tends to prevail over verbal engagements.

Magnetic resonance imaging of the preterm infant brain.

Despite improvements in neonatal care, survivors of preterm birth are still at a significantly increased risk of developing life-long neurological difficulties including cerebral palsy and cognitive difficulties. Cranial ultrasound is routinely used in neonatal practice, but has a low sensitivity for identifying later neurodevelopmental difficulties. Magnetic Resonance Imaging (MRI) can be used to identify intracranial abnormalities with greater diagnostic accuracy in preterm infants, and theoretically might improve the planning and targeting of long-term neurodevelopmental care; reducing parental stress and unplanned healthcare utilisation; and ultimately may improve healthcare cost effectiveness. Furthermore, MR imaging offers the advantage of allowing the quantitative assessment of the integrity, growth and function of intracranial structures, thereby providing the means to develop sensitive biomarkers which may be predictive of later neurological impairment. However further work is needed to define the accuracy and value of diagnosis by MR and the techniques's precise role in care pathways for preterm infants.

Development of the optic radiations and visual function after premature birth.

INTRODUCTION: Visual impairment in preterm infants at term equivalent age (TEA) is associated with impaired microstructural development in the optic radiation, measured as reduced fractional anisotropy (FA) by Diffusion Tensor Imaging (DTI). We tested the hypothesis that these abnormalities develop during the late preterm period. METHODS: DTI was performed in 53 infants born at a median (range) of 30(+1) (25(+4)-34(+6)) weeks post-menstrual age (PMA), 22 of whom were imaged twice. RESULTS: FA in the optic radiation at TEA was related to: visual function (p = .003); PMA at birth (p = .015); and PMA at scan (p = .008); while a significant interaction between PMA at birth and scan (p = .019) revealed an effect of the period of premature extra-uterine life additional to the degree of prematurity. We explored this further in a sub-group of 22 infants who were studied twice. FA increased from mean (95% CI) .174 (.164-.176) on the first image at 32(+5) (29(+5)-36) weeks PMA, to .198 (.190-.206) on the second image at 40(+6) (39(+2)-46) weeks PMA. Visual function was not predicted by FA on the images obtained in the early neonatal period, but was significantly related to the rate of increase in FA between scans (p = .027) and to FA on the second image (p = .015). CONCLUSION: Microstructural maturation during the late preterm period is thus required for normal visual function, suggesting that interventions applied after 30 weeks PMA might reduce impairment in preterm infants.

Effects of carbohydrate counting on glucose control and quality of life over 24 weeks in adult patients with type 1 diabetes on continuous subcutaneous insulin infusion: a randomized, prospective clinical trial (GIOCAR).

OBJECTIVE: Few studies have assessed the efficacy of carbohydrate counting in type 1 diabetes, and none have validated its efficacy in patients who are treated with continuous subcutaneous insulin infusion (CSII). The aim of our study was to test the effect of carbohydrate counting on glycemic control and quality of life in adult patients with type 1 diabetes who are receiving CSII. RESEARCH DESIGN AND METHODS: Sixty-one adult patients with type 1 diabetes treated with CSII were randomly assigned to either learning carbohydrate counting (intervention) or estimating pre-meal insulin dose in the usual empirical way (control). At baseline and 12 and 24 weeks, we measured HbA(1c), fasting plasma glucose, BMI, waist circumference, recorded daily insulin dose, and capillary glucose data, and administered the Diabetes-Specific Quality-of-Life Scale (DSQOLS) questionnaire. RESULTS: Intention-to-treat analysis showed improvement of the DSQOLS score related to diet restrictions (week 24 - baseline difference, P = 0.008) and reduction of BMI (P = 0.003) and waist circumference (P = 0.002) in the intervention group compared with control subjects. No changes in HbA(1c), fasting plasma glucose, daily insulin dose, and hypoglycemic episodes (<2.8 mmol/L) were observed. Per-protocol analysis, including only patients who continuously used carbohydrate counting and CSII during the study, confirmed improvement of the DSQOLS score and reduction of BMI and waist circumference, and showed a significant reduction of HbA(1c) (-0.35% vs. control subjects, P = 0.05). CONCLUSIONS: Among adult patients with type 1 diabetes treated with CSII, carbohydrate counting is safe and improves quality of life, reduces BMI and waist circumference, and, in per-protocol analysis, reduces HbA(1c).

Diffusion tensor imaging in preterm infants with punctate white matter lesions.

Our aim was to compare white matter (WM) microstructure in preterm infants with and without punctate WM lesions on MRI using tract-based spatial statistics (TBSS) and probabilistic tractography. We studied 23 preterm infants with punctate lesions, median GA at birth 30 (25-35) wk, and 23 GA- and sex-matched preterm controls. TBSS and tractography were performed to assess differences in fractional anisotropy (FA) between the two groups at term equivalent age. The impact of lesion load was assessed by performing linear regression analysis of the number of lesions on term MRI versus FA in the corticospinal tracts in the punctate lesions group. FA values were significantly lower in the posterior limb of the internal capsule, cerebral peduncles, decussation of the superior cerebellar peduncles, superior cerebellar peduncles, and pontine crossing tract in the punctate lesions group. There was a significant negative correlation between lesion load at term and FA in the corticospinal tracts (p = 0.03, adjusted r² = 0.467). In conclusion, punctate lesions are associated with altered microstructure in the WM fibers of the corticospinal tract at term equivalent age.

A dynamic 4D probabilistic atlas of the developing brain.

Probabilistic atlases are widely used in the neuroscience community as a tool for providing a standard space for comparison of subjects and as tissue priors used to enhance the intensity-based classification of brain MRI. Most efforts so far have focused on static brain atlases either for adult or pediatric cohorts. In contrast to the adult brain the rapid growth of the neonatal brain requires an age-specific spatial probabilistic atlas to provide suitable anatomical and structural information. In this paper we describe a 4D probabilistic atlas that allows dynamic generation of prior tissue probability maps for any chosen stage of neonatal brain development between 29 and 44 gestational weeks. The atlas is created from the segmentations of 142 neonatal subjects at different ages using a kernel-based regression method and provides prior tissue probability maps for six structures - cortex, white matter, subcortical grey matter, brainstem, cerebellum and cerebro-spinal fluid. The atlas is publicly available at www.brain-development.org.

Emergence of resting state networks in the preterm human brain.

The functions of the resting state networks (RSNs) revealed by functional MRI remain unclear, but it has seemed possible that networks emerge in parallel with the development of related cognitive functions. We tested the alternative hypothesis: that the full repertoire of resting state dynamics emerges during the period of rapid neural growth before the normal time of birth at term (around 40 wk of gestation). We used a series of independent analytical techniques to map in detail the development of different networks in 70 infants born between 29 and 43 wk of postmenstrual age (PMA). We characterized and charted the development of RSNs from recognizable but often fragmentary elements at 30 wk of PMA to full facsimiles of adult patterns at term. Visual, auditory, somatosensory, motor, default mode, frontoparietal, and executive control networks developed at different rates; however, by term, complete networks were present, several of which were integrated with thalamic activity. These results place the emergence of RSNs largely during the period of rapid neural growth in the third trimester of gestation, suggesting that they are formed before the acquisition of cognitive competencies in later childhood.

An optimised tract-based spatial statistics protocol for neonates: applications to prematurity and chronic lung disease.

Preterm birth is associated with altered white matter microstructure, defined by metrics derived from diffusion tensor imaging (DTI). Tract-based spatial statistics (TBSS) is a useful tool for investigating developing white matter using DTI, but standard TBSS protocols have limitations for neonatal studies. We describe an optimised TBSS protocol for neonatal DTI data, in which registration errors are reduced. As chronic lung disease (CLD) is an independent risk factor for abnormal white matter development, we investigate the effect of this condition on white matter anisotropy and diffusivity using the optimised protocol in a proof of principle experiment. DTI data were acquired from 93 preterm infants (48 male) with a median gestational age at birth of 28(+5) (23(+4)-35(+2))weeks at a median postmenstrual age at scan of 41(+4) (38(+1)-46(+6))weeks. Nineteen infants developed CLD, defined as requiring supplemental oxygen at 36weeks postmenstrual age. TBSS was modified to include an initial low degrees-of-freedom linear registration step and a second registration to a population-average FA map. The additional registration steps reduced global misalignment between neonatal fractional anisotropy (FA) maps. Infants with CLD had significantly increased radial diffusivity (RD) and significantly reduced FA within the centrum semiovale, corpus callosum and inferior longitudinal fasciculus (p<0.05) compared to their peers, controlling for degree of prematurity and age at scan. The optimised TBSS protocol improved reliability for neonatal DTI analysis. These data suggest that potentially modifiable respiratory morbidity is associated with widespread altered white matter microstructure in preterm infants at term-equivalent age.

Antepartum and intrapartum risk factors for neonatal encephalopathy at term.

We investigated antepartum and intrapartum risk factors for neonatal encephalopathy (NE) in term infants. We performed a case-controlled study in which characteristics of singleton term infants who developed NE from 1993 to 2003 were compared with those of randomly selected controls. Antenatal risk factors (including obesity, diabetes, thyroid dysfunction, previous cesarean delivery, preeclampsia, fetal growth restriction, abnormal amniotic fluid volume, and abnormal fetal heart rate [FHR] tracing before labor) and intrapartum risk factors (acute intrapartum sentinel events and other risk factors like suspicious or ominous FHR tracing and clinical chorioamnionitis) were related to occurrence of NE. From the study cohort of 30,580 infants, 27 (0.09%) developed NE and were compared with 100 controls. Neonates with encephalopathy had more frequent antepartum (74% versus 18%, P < 0.001) and intrapartum (67% versus 19%, P < 0.001) risk factors, including acute intrapartum events (33% versus 2%, P < 0.001), than controls. On the whole, 26% of cases of NE had only antepartum risk factors, 22% had only intrapartum risk factors, and 44% had a combination of the two. In 2/27 (7%) cases, no risk factors were recognizable. In conclusion, 44% of cases of NE following term deliveries can be attributed to a combination of antepartum and intrapartum variables.

Developmental change in fetal response to repeated low-intensity sound.

The aim of this study was to investigate developmental changes in heart rate response to repeated low-intensity (85 dB) sound stimulation in fetuses between 32 and 37 weeks of gestation. We measured amplitude changes in heart rate as our index of fetal response. At 35 to 37 weeks of gestation, the majority of fetuses showed a deceleratory response at the first trial. Amplitude decreased with further trials using the same stimulus before recovering when exposed to another type of stimulation. In contrast, responses in fetuses at 32 to 34 weeks of gestation were variable across trials and there was no recovery with exposure to another type of stimulation. Our results suggest that fetal habituation of cardiac response changes with developmental age.

Factors affecting survival in infants weighing 750 g or less.

OBJECTIVE: To assess which factors independently affect survival in infants weighing 750g or less. STUDY DESIGN: We reviewed the obstetric, neonatal, and placental pathology information of all non-malformed neonates with birth weight of 750g or less from January 1998 to December 2002. Logistic regression analysis was used to control for the effect of confounding variables. A P<0.05 was considered significant. RESULTS: Fifty nine neonates fulfilled the inclusion criteria; 30 (51%) survived the perinatal period. Surviving neonates were more frequently born after steroid administration (P=0.03) and from indicated delivery (P=0.01), had greater birth weight (P=0.001), gestational age at delivery (P<0.001), and 5-min Apgar scores of 7 or more (P=0.04) than those who died. There were no significant differences in placental pathology between survivors and neonates who died. Stepwise logistic regression analysis showed that gestational age (P=0.01), birth weight (P=0.004), female sex (P=0.03), 5-min Apgar score (0.026), and steroid administration (P=0.04) were independent predictors of survival. Cumulatively these five predictors explained 69% of neonatal survival. CONCLUSIONS: The predictors of survival among micropremies are the same as those reported for older preterm neonates. The type of preterm delivery (spontaneous versus indicated) and placental pathology do not independently affect survival.

Gestational age at preterm premature rupture of membranes: a risk factor for neonatal white matter damage.

OBJECTIVE: Gestational age at delivery and spontaneous prematurity are independent risk factors for white matter damage (WMD). However, among infants delivered spontaneously after preterm premature rupture of membranes (PPROM), latency of PPROM has been inconsistently correlated with risk of WMD. We have explored whether gestational age at membrane rupture is independently associated with WMD. STUDY DESIGN: Using a cohort of 196 liveborn singleton nonanomalous neonates born at 24.0 to 33.6 weeks from January 1993 to December 2002 after pPROM and who survived 7 days, we compared the characteristics of those who developed WMD (n = 15) with those who did not (n = 181) using Fisher exact test, Student t test, and logistic regression analysis, with a 2-tailed P < .05 or odds ratio (OR) with 95% CI not inclusive of the unity considered significant. RESULTS: Stepwise logistic regression analysis demonstrated that gestational age at PPROM (P < .001, OR 0.79) was significantly associated with WMD. The association was independent of corticosteroid administration (P = .016), latency interval (P = .69), gestational age at delivery (P = .99), and birth weight (P = .62). CONCLUSION: Among premature infants born at <34 weeks after pPROM, gestational age at diagnosis is independently associated with WMD.

Intraventricular hemorrhage and periventricular leukomalacia in preterm infants.

OBJECTIVE: To evaluate whether intraventricular hemorrhage and periventricular leukomalacia are characterized by different risk factors. METHODS: In a cohort of 653 consecutive singleton neonates born after preterm membrane rupture, spontaneous preterm labor, or indicated preterm delivery at 24 to 33 weeks of gestation from January 1, 1993, to December 31, 2002, we evaluated the obstetric and histopathologic placental variables in reference to the development of intraventricular hemorrhage (n = 44), periventricular leukomalacia (n = 19), or no ultrasonographic cerebral lesion (n = 589). Excluded were stillbirths and congenital anomalies. Statistical analysis included Fisher exact test, Student t test, and stepwise logistic regression analysis with a 2-tailed P <.05 considered significant. RESULTS: Multivariate analysis showed that occurrence of neonatal intraventricular hemorrhage and periventricular leukomalacia were associated only with spontaneous prematurity (odds ratio = 1.9; 95% confidence interval 1.1-3.4) and gestational age at delivery in weeks (odds ratio = 0.8; 95% confidence interval 0.7-0.9). Neonates with intraventricular hemorrhage did not differ from those with periventricular leukomalacia in any obstetric or neonatal variable, but there was a higher risk of neurodevelopmental delay associated with periventricular leukomalacia. CONCLUSION: Among premature infants born at less than 34.0 weeks of gestation, intraventricular hemorrhage and periventricular leukomalacia share common clinical characteristics, with spontaneous preterm delivery and gestational age at delivery as the only independent antenatal predictors.