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Abstract: Aims: Classical microbiology techniques are the gold standard for probiotic enumeration. However, these techniques are limited by parameters of time, specificity and incapacity to detect viable but nonculturable (VBNC) micro‐organisms and nonviable cells. The aim of the study was to evaluate flow cytometry as a novel method for the specific quantification of viable and nonviable probiotics in multistrain products. Methods and Results: Custom polyclonal antibodies were produced against five probiotic strains from different species (Bifidobacterium bifidum R0071, Bifidobacterium longum ssp. infantis R0033, Bifidobacterium longum ssp. longum R0175, Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011). Evaluation of specificity confirmed that all antibodies were specific at least at the subspecies level. A flow cytometry method combining specific antibodies and viability assessment with SYTO®24 and propidium iodide was applied to quantify these strains in three commercial products. Analyses were conducted on two flow cytometry instruments by two operators and compared with classical microbiology using selective media. Results indicated that flow cytometry provides higher cell counts than classical microbiology (P < 0·05) in 73% of cases highlighting the possible presence of VBNC. Equivalent performances (repeatability and reproducibility) were obtained for both methods. Conclusions: This study showed that flow cytometry methods can be applied to probiotic enumeration and viability assessment. Combination with polyclonal antibodies can achieve sufficient specificity to differentiate closely related strains. Significance and Impact of the Study: Flow cytometry provides absolute and specific quantification of viable and nonviable probiotic strains in a very short time (<2 h) compared with classical techniques (>48 h), bringing efficient tools for research and development and quality control. [ABSTRACT FROM AUTHOR]

Unlabelled: The European Paediatric Regulation mandated the European Commission to fund research on off-patent medicines with demonstrated therapeutic interest for children. Responding to this mandate, five FP7 project calls were launched and 20 projects were granted. This paper aims to detail the funded projects and their preliminary results. Publicly available sources have been consulted and a descriptive analysis has been performed. Twenty Research Consortia including 246 partners in 29 European and non-European countries were created (involving 129 universities or public-funded research organisations, 51 private companies with 40 SMEs, 7 patient associations). The funded projects investigate 24 medicines, covering 10 therapeutic areas in all paediatric age groups. In response to the Paediatric Regulation and to apply for a Paediatric Use Marketing Authorisation, 15 Paediatric Investigation Plans have been granted by the EMA-Paediatric Committee, including 71 studies of whom 29 paediatric clinical trials, leading to a total of 7,300 children to be recruited in more than 380 investigational centres.Conclusion: Notwithstanding the EU contribution for each study is lower than similar publicly funded projects, and also considering the complexity of paediatric research, these projects are performing high-quality research and are progressing towards the increase of new paediatric medicines on the market. Private-public partnerships have been effectively implemented, providing a good example for future collaborative actions. Since these projects cover a limited number of off-patent drugs and many unmet therapeutic needs in paediatrics remain, it is crucial foreseeing new similar initiatives in forthcoming European funding programmes. [ABSTRACT FROM AUTHOR]

The European Paediatric Regulation mandated the European Commission to fund research on off-patent medicines with demonstrated therapeutic interest for children. Responding to this mandate, five FP7 project calls were launched and 20 projects were granted. This paper aims to detail the funded projects and their preliminary results. Publicly available sources have been consulted and a descriptive analysis has been performed. Twenty Research Consortia including 246 partners in 29 European and non-European countries were created (involving 129 universities or public-funded research organisations, 51 private companies with 40 SMEs, 7 patient associations). The funded projects investigate 24 medicines, covering 10 therapeutic areas in all paediatric age groups. In response to the Paediatric Regulation and to apply for a Paediatric Use Marketing Authorisation, 15 Paediatric Investigation Plans have been granted by the EMA-Paediatric Committee, including 71 studies of whom 29 paediatric clinical trials, leading to a total of 7,300 children to be recruited in more than 380 investigational centres. Conclusion: Notwithstanding the EU contribution for each study is lower than similar publicly funded projects, and also considering the complexity of paediatric research, these projects are performing high-quality research and are progressing towards the increase of new paediatric medicines on the market. Private-public partnerships have been effectively implemented, providing a good example for future collaborative actions. Since these projects cover a limited number of off-patent drugs and many unmet therapeutic needs in paediatrics remain, it is crucial foreseeing new similar initiatives in forthcoming European funding programmes. [ABSTRACT FROM AUTHOR]

In the present work, the coupling of adsorption and electrochemical oxidation on a boron-doped diamond (BDD) electrode to treat solutions containing dyes is studied. This coupling may be convenient for the treatment of diluted pollutant that is limited by the low rate of electrooxidation due to mass-transfer limitation. A pre-concentration step by adsorption could minimize the design of the electrochemical reactor. The adsorbent chosen was mixed with softwood sawdust, and methylene blue was chosen as the model dye molecule. Isotherms of adsorption and kinetics were investigated as well as the effects of current density and regeneration time. The BDD electrochemical oxidation of methylene blue adsorbed onto sawdust led simultaneously to its degradation and sawdust regeneration for the next adsorption. It was observed that multiple adsorption and electrochemical regeneration cycles led to an enhancement of adsorption capacity of the sawdust. This study demonstrated that adsorption-electrochemical degradation coupling offers a promising approach for the efficient elimination of organic dyes from wastewater. [ABSTRACT FROM AUTHOR]

Background: Use of the antiepileptic drug vigabatrin is associated with an elevated risk of visual field loss.Objective: To determine the frequency of, and risk factors for, vigabatrin-attributed visual field loss (VAVFL) in the setting of a large-scale, multinational, prospective, observational study.Study Design: A comparative, open-label, parallel-group, multicentre study.Setting: Hospital outpatient clinics at 46 centres in five countries.Patients: 734 patients with refractory partial epilepsy, divided into three groups and stratified by age (8-12 years; >12 years) and exposure to vigabatrin. Group I comprised patients treated with vigabatrin for > or =6 months. Group II comprised patients previously treated with vigabatrin for > or =6 months who had withdrawn from the drug for > or =6 months. Group III comprised patients never treated with vigabatrin. Patients underwent perimetry at either 4- or 6-month intervals, for up to 36 months. Visual field outcome was evaluated masked to drug exposure.Intervention: Perimetry.Main Outcome Measure: The visual field outcome at each of four analysis points: (i) at enrolment (i.e. baseline, all patients); (ii) for patients exhibiting a conclusive outcome at the initial visual field examination; (iii) for patients exhibiting at least one conclusive outcome to the visual field examinations; and (iv) at the last conclusive outcome to the visual field examinations.Results: Of the 734 patients, 524 yielded one or more conclusive visual field examinations. For Group I, the frequency of VAVFL at the last conclusive examination was 10/38 (26.3%) for those aged 8-12 years and 65/150 (43.3%) for those aged >12 years. For Group II, the respective frequencies were 7/47 (14.9%) and 37/151 (24.5%). One case resembling VAVFL was present amongst the 186 patients in Group III at the last conclusive examination. The frequency of VAVFL in Groups I and II combined was 20.0% for those aged 8-12 years and 33.9% for those aged >12 years. VAVFL was associated with duration of vigabatrin therapy (odds ratio [OR] up to 15.2; 95% CI 4.4, 51.7), mean daily dose of vigabatrin (OR up to 26.4; 95% CI 2.4, 291.7) and male gender (OR 2.51; 95% CI 1.5, 4.1). VAVFL was more frequently detected with static than with kinetic perimetry (OR up to 0.43; 95% CI 0.24, 0.75).Conclusions: Since the probability of VAVFL is positively associated with treatment duration, careful assessment of the risk-benefit ratio of continuing treatment with vigabatrin is recommended in patients currently receiving this drug. All patients continuing to receive vigabatrin should undergo visual field examination at least every 6 months for the duration of treatment. We recommend two-level (three-zone), gradient-adapted, suprathreshold static perimetry of the peripheral field together with threshold perimetry of the central field out to 30 degrees from fixation. The frequency of ophthalmological and perimetric examinations should be increased in the presence of VAVFL. [ABSTRACT FROM AUTHOR]

Abstract We have determined the properties of seizures induced in vitro during the first postnatal days using intact rat cortico-hippocampal formations (CHFs) and extracellular recordings. Two main patterns of activity were generated by nominally Mg2+ -free ACSF in hippocampal and cortical regions: ictal-like events (ILEs) and late recurrent interictal discharges (LRDs). They were elicited at distinct developmental periods and displayed different pharmacological properties. ILEs were first observed in P1 CHFs 52 ± 7 min after application of low-Mg2+ ACSF (frequency 1.5 ± 0.3 h-1 , duration 86 ± 3 s). There is a progressive age-dependent maturation of ILEs characterized by a decrease in their onset and an increase in their frequency and duration. ILEs were abolished by d-APV and Mg2+ ions. From P7, ILEs were followed by LRDs that appeared 89 ± 8 min after application of low-Mg2+ ACSF (frequency ≈ 1 Hz, duration 0.66 s, amplitude 0.31 ± 0.03 mV). LRDs were no longer sensitive to d-APV or Mg2+ ions and persisted for at least 24 h in low-Mg2+ or in normal ACSF. ILEs and LRDs were synchronized in limbic and cortical regions with 10–40 ms latency between the onsets of seizures. Using a double chamber that enables independent superfusion of two interconnected CHFs, we report that ILEs and LRDs generated in one CHF propagated readily to the other one that was being kept in ACSF. Therefore, at a critical period of brain development, recurrent seizures induce a permanent form of hyperactivity in intact brain structures and this preparation provides a unique opportunity to study the consequences of seizures at early developmental stages. [ABSTRACT FROM AUTHOR]

In children with medically intractable lesional epilepsy, surgery is deemed successful if the epileptogenic focus can be removed while major neurological functions are spared. Current techniques rely on invasive intracranial recordings. The new developments in functional imaging offer the possibility of localizing the epileptogenic focus noninvasively (PET/SPECT) and mapping cognitive functions (fMRI). Ictal SPECT shows hyperperfusion in the focus and has proved to have better localizing value than interictal PET or SPECT, which show focal hypometabolism or hypoperfusion. Ictal SPECT is useful for deciding on the placement of intracranial electrodes in extratemporal epilepsies, particularly in young children. Functional MRI has proved highly accurate for localizing motor and language networks, thus offering the possibilities of replacing the Wada test (language hemispheric lateralization) and studying postlesional brain plasticity. Despite the difficulties of functional imaging in children owing to the limited cooperation that can be expected, ethical constraints, and poor normative data, SPECT/PET and fMRI provide clinically useful information for presurgical work-up of childhood epilepsies. [ABSTRACT FROM AUTHOR]

Objectives: Intraventricular astrocytomas (subependymal giant cell astrocytomas) of tuberous sclerosis have a poor prognosis due to the obstruction of CSF flow. The aim of this study was to determine whether they could be differentiated during childhood and at an early preclinical stage, from subependymal nodules without any growing potential.Methods: The first two MRIs of all children referred to this neuropaediatric centre between 1987 and 1996 were retrospectively blindly reviewed.Results: Out of 60 patients, 24 disclosed subependymal nodules localised near the foramen of Monro, and eight of the 24 developed astrocytomas. Subependymal nodules were first detectable on MRI from 1 year of age in all cases and the first MRI evidence of growth occurred between 1 and 9 years (mean 4 years). At an early stage, subependymal nodules had different characteristics in patients who developed subependymal giant cell astrocytomas from those who did not. The nodules over 5 mm in diameter that were incompletely calcified and enhanced by gadolinium were at higher risk of growing, particularly in children with a familial history of tuberous sclerosis. To detect the subependymal giant cell astrocytomas earlier in tuberous sclerosis, it is advisible to systematically perform an MRI examination before 2 years of age and to repeat it every year if the patient has risk factors for developing astrocytomas. [ABSTRACT FROM AUTHOR]

Objectives: Autistic disorder is a developmental handicap with an unknown neurological basis. Current neuropsychological models for autism suggest an abnormal construction of visual perceptual representation or a deficit in executive functions. These models predict cerebral lesions in the temporo-occipital or frontal regions of autistic patients. The present study aimed at studying the presence of symptoms of autism and visual agnosia in a 13 year old girl who had a right temporo-occipital cortical dysplasia that was surgically removed at the age of 7.Methods: Neuropsychological evaluation included Wechsler and Kaufman intelligence scales, a test of word fluency, digit span, Corsi block, California verbal learning, Trail making, Benton facial recognition, Snoodgrass object recognition tests, Rivermead face learning subtest, and developmental test of visual perception. The ADI-R was used to show current and retrospective diagnosis of autistic disorder. Neuroimagery included brain MRI, single photon emission computed tomography (SPECT), and PET.Results: Brain MRI showed a right occipital defect and an abnormal hyperintensity of the right temporal cortex. PET and SPECT disclosed a left frontal hypometabolism together with the right occipital defect. Neuropsychological testing showed a visual apperceptive agnosia and executive function deficits. Psychiatric study confirmed the diagnosis of autistic disorder.Conclusions: Although the possibility that autism and visual agnosia were dissociable factors in this patient cannot be excluded, the finding of both deficits supports the possibility that occipito-temporal lesions can predispose to the development of autism. [ABSTRACT FROM AUTHOR]

Objectives: Functional cerebral imaging PET and SPECT have shown hypometabolism and hypoperfusion in the area of vascular malformation in children with epilepsy due to Sturge-Weber syndrome. However, data are scarce in infants and do not exist in patients with Sturge-Weber disease without epilepsy. The pattern of perfusion during the first two years of life was studied including patients before the onset of seizures.Methods: Twenty two infants with later confirmed Sturge-Weber disease underwent SPECT examination using TOMOMATIC 564 (Medimatic) and xenon-133 at ages ranging from 8 days to 25 months. Twelve had never had seizures before SPECT and seven underwent a second SPECT a mean seven months later. Cerebral blood flow (CBF) was measured in the whole hemisphere and in the part of the cortex involved in the vascular malformation on both sides as well as a "pathological to normal" index for the hemisphere and vascular malformation. These values were compared with normal age paired values.Results: Compared with controls, CBF and the indices in the hemisphere and vascular malformation were significantly decreased in patients who already had had seizures before SPECT, whereas they were significantly increased in 75% of the patients who had never had any seizures. On second SPECT, the indices were decreased in all patients, including the four who still remained non-epileptic.Conclusions: SPECT therefore detects CBF asymmetry in infants with Sturge-Weber disease, which tends to shift with age. The cortex involved in the vascular malformation is hyperperfused during the first year of life before first seizures. The classic hypoperfusion appears after one year of age, even in non-epileptic patients. [ABSTRACT FROM AUTHOR]

Neuronal migration disorders can now be recognised by MRI. This paper reports two families in which the mothers had subcortical laminar heterotopia and four of their children had either similar heterotopia (two girls) or severe pachygyria or lissencephaly (two boys). Laminar heterotopia was more evident on MRI T2 weighted images. The patients had mild to severe epilepsy and mental retardation depending on the extent of cortical abnormalities. In these families, subcortical laminar heterotopia, pachygyria, and lissencephaly seem to share the same X linked or autosomal dominant gene. No chromosomal abnormalities, especially of chromosome 17, could be identified. For appropriate genetic counselling of the family of a child with lissencephaly or subcortical laminar heterotopia, MRI should be performed in parents or siblings with mental retardation or epilepsy. [ABSTRACT FROM AUTHOR]

Regional cerebral blood flow (rCBF) was studied using SPECT (single photon emission computed tomography) with 133-Xenon in 13 patients with confirmed Sturge-Weber disease, aged 9 months to 18 years. CT scan, performed at the same time, showed evident cerebral angioma in 10 but not in three. A marked hypoperfused area was found in all patients, ranging from -32% to -72% and of the same location as the CT signs. The hypoperfusion seems to result from post ictal phenomenon as well as from chronic ischaemia. SPECT imaging is therefore a sensitive method for visualising intracranial angioma in Sturge-Weber disease and it provides an aid for diagnosis when a CT scan is not reliable. [ABSTRACT FROM AUTHOR]

Objective: To study the relationship between the plasma concentration of stiripentol (STP), a new antiepileptic drug, and its inhibitory effect on the formation of carbamazepine epoxide (CBZE) in epileptic children treated with carbamazepine (CBZ) either alone or in combination with another antiepileptic drug. Methods: Minimum plasma concentration of antiepileptic drugs was measured before initiation of STP therapy (day 0) and on days 28 (STP 60 mg⋅kg⋅day) and 84 (STP 90 mg⋅kg⋅day) by HPLC. Results: The CBZE/CBZ plasma concentration ratio decreased exponentially with increasing minimum plasma STP concentration ( r = 0.80). The asymptote of the curve allowed the calculation of the minimum plasma STP concentration required to obtain the maximum inhibitory effect, i.e. 6.7 mg⋅l. Conclusion: The inhibitory effect of STP on CBZ metabolism expressed as the CBZE/CBZ plasma concentration ratio is dependent on STP plasma concentration, with a maximum effect at an average of 7 mg⋅l. The present data suggest that in order to evaluate the anticonvulsant efficacy of STP as add-on therapy, the minimum plasma STP concentration should be maintained above 7 mg⋅l and the dosage of CBZ should simultaneously be decreased in steps by more than 50% to minimize the change in CBZ plasma concentration. [ABSTRACT FROM AUTHOR]

1. The pharmacokinetics of the enantiomers of vigabatrin were investigated after oral administration of a single 50 mg kg-1 dose of the racemate to two groups of six epileptic children (I: 5 months-2 years, II: 4-14 years). 2. The mean (+/− s.d.) values of maximum plasma concentration and area under the plasma concentration-time curve of the R(-) enantiomer were significantly higher than those of S(+) vigabatrin in both groups: R(-) Cmax: 21 +/− 6.6 (I)-41.3 +/− 13.9 (II) vs S(+) Cmax: 13.9 +/− 4.5 (I)-23.8 +/− 12.2 (II) mg l-1; R(-) AUC: 106 +/− 28.5 (I)-147 +/− 34 (II) vs S(+) AUC: 90.9 +/− 27.9 (I)-117 +/− 26 (II) mg l-1 h. In group I, the half-life of the R(-) isomer was significantly shorter than that of the S(+) isomer; in group II, the half-lives were comparable. 3. For the R(-) enantiomer the area under the curve, and the elimination half-life increased linearly with age. 4. During chronic administration (50 mg kg-1 vigabatrin racemate twice a day for 4 days), the morning trough plasma drug concentrations did not increase. [ABSTRACT FROM AUTHOR]

The prognosis of Sturge-Weber syndrome (SWS) is partly related to early occurrence of seizures but the diagnosis of this phakomatosis may be difficult during the 1st year of life. We have performed a retrospective study of seven patients with confirmed SWS (age 7 days to 3 months). None of the patients was asymptomatic at the time of the study. They all underwent MRI (T1 and T2 sequences) and single photon emission computed tomography (SPECT) at the same time. Regional cerebral blood flow was measured using xenon-133. In all cases, myelination appeared to be accelerated in the areas underlying the leptomeningeal angioma on both MRI sequences. In five cases, SPECT showed hyperperfusion in the damaged hemisphere. In one case, the SPECT was symmetrical and in another it showed hypoperfusion in the damaged hemisphere which was already atrophied. These data suggest that the accelerated myelination is not related to ischemia but to transient hyperperfusion. This MRI pattern can be helpful for the early diagnosis of SWS, which is of utmost importance for preventive antiepileptic treatment. [ABSTRACT FROM AUTHOR]

The antiepileptic drug vigabatrin (VGB) is a selective irreversible inhibitor of GABA-transaminase. It is administered as a racemic R(−), S(+) mixture, but the pharmacological activity of vigabatrin resides in the S(+) enantiomer and the R(−) enantiomer is inactive. The pharmacokinetic parameters of the two enantiomers have been studied after administration of a single oral 125 mg dose of the racemate to six neonates. The mean values of Cmax and AUC of the S(+) enantiomer were significantly lower ( Cmax : 14.0±4.3 mg l−1; AUC: 143±44 mg l−1 h) than those of the R(−) enantiomer ( Cmax: 34.1±9.5 mg l−1; AUC: 231±88 mg l−1 h), whereas no significant difference in the time to reach Cmax (S(+): 2.1±1.1 h; R(−): 2.2±1 h) was observed between the two enantiomers. During chronic administration (125 mg twice daily over 4 days), there was no evidence of accumulation of either enantiomer. [ABSTRACT FROM AUTHOR]