Multiple acyl-CoA dehydrogenase deficiency (MADD) as a cause of late-onset treatable metabolic disease.

INTRODUCTION: Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is a rare, treatable, beta-oxidation disorder responsible for neuromuscular symptoms in adults. This case series describes the clinical and biochemical features of 13 French patients with late-onset MADD. METHODS AND RESULTS: Thirteen ambulant patients (eight women, five men), with a median age at onset of 27 years, initially experienced exercise intolerance (n=9), isolated muscle weakness (n=1) and a multisystemic pattern with either central nervous system or hepatic dysfunction (n=3). During the worsening period, moderate rhabdomyolysis (n=5), a pseudomyasthenic pattern (n=5) and acute respiratory failure (n=1) have been observed. Weakness typically affected the proximal limbs and axial muscles, and there was sometimes facial asymmetry (n=3). Moderate respiratory insufficiency was noted in one case. Median baseline creatine kinase was 190IU/L. Lactacidemia was sometimes moderately increased at rest (3/10) and after exercise (1/3). The acylcarnitine profile was characteristic, with increases in all chain-length acylcarnitine species. Electromyography revealed a myogenic pattern, while muscle biopsy showed lipidosis, sometimes with COX-negative fibers (n=2). The mitochondrial respiratory chain was impaired in five cases, with coenzyme Q10 decreased in two cases. All patients harbored mutations in the ETFDH gene (four homozygous, seven compound heterozygous, two single heterozygous), with nine previously unidentified mutations. All patients were good responders to medical treatment, but exercise intolerance and/or muscular weakness persisted in 11 of them. CONCLUSION: Late-onset forms of MADD may present as atypical beta-oxidation disorders. Acylcarnitine profiling and muscle biopsy remain the most decisive investigations for assessing the diagnosis. These tests should thus probably be performed more widely, particularly in unexplained cases of neuromuscular and multisystemic disorders.

Neurodevelopmental long-term outcome in children with hydrocephalus requiring neonatal surgical treatment.

PURPOSE: To assess long-term neurodevelopmental outcome in children with hydrocephalus requiring neurosurgical treatment during the neonatal period. METHODS: This prospective longitudinal population-based study included 43 children with neonatal shunted hydrocephalus. The 43 children were prospectively reviewed in the presence of their parents at the outpatient clinic. Cognitive and motor outcomes were assessed respectively using different Wechsler scales according to age and Gross Motor Function Classification System (GMFCS). Postoperative MRI was routinely performed. RESULTS: The mean gestational age at birth of the 43 consecutive children with neonatal hydrocephalus (sex ratio M/F: 1.39) was 34.5±5.4 weeks of gestation. At mean follow-up of 10.4±4 years, mean total IQ was 73±27.7, with equivalent results in mean verbal and mean performance IQ. Of the 33 children with IQ evaluation, 18 presented an IQ≥85 (41.9%). Efficiency in walking without a mobility device (GMFCS≤2) was obtained in 37 children (86%). Only severity of postoperative ventricular dilation was significantly associated with unfavorable outcome (Evans index>0.37; odds ratio: 0.16, P=0.03). CONCLUSION: This information could be provided to those families concerned who often experience anxiety when multi-disciplinary management of neonatal hydrocephalus is required.

[Course and neurological/behavioral development of preterm children]. / Parcours et développement neurologique et comportemental de l'enfant prématuré

Preterm birth remains a public health priority given that one child out of ten is born before 37 weeks of gestation. Survival without major neonatal morbidity has increased in high-income countries, in particular in France and in cases of extreme preterm birth before 27 weeks of gestation. Rate of severe handicaps, such as cerebral palsy, is probably decreasing, but specific cognitive disabilities in a variety of domains remain frequent, interfering with normal learning abilities at school and explaining the high rate of special education needs. Prevalence of sequelae increases when gestational age at birth decreases. However, because there are more moderate to late preterm children compared to very preterm children, the absolute number of children with specific cognitive or neurological disabilities is equivalent in these two groups. Better characterization of the development in a recent cohort of very preterm children is necessary to improve the early detection of variations in normal neurodevelopment and to propose trials with remediation actions targeting working memory and language for example. These protocols could decrease the rates of learning disabilities at school.

Molecular mechanisms involved in HIV-1 transcriptional latency and reactivation: implications for the development of therapeutic strategies.

The persistence of latently HIV-infected cellular reservoirs, despite prolonged treatment with ART (antiretroviral therapy), represents the major hurdle to virus eradication. These latently infected cells are a permanent source for virus reactivation and lead to a rebound of the viral load after interruption of ART. Therefore, a greater understanding of the molecular mechanisms regulating viral latency and reactivation should lead to rational strategies aimed at purging the latent HIV reservoirs. Our laboratory is studying elements critical for the mechanisms of viral transcriptional reactivation including: 1) the transcription factor NF-kB, which is induced by proinflammatory cytokines (such as TNFalpha) and binds to two sites kB in the HIV-1 promoter region; 2) the specific remodeling of a single nucleosome (called nuc-1 and located immediately downstream of the HIV transcription start site under latency conditions) upon activation of the HIV-1 promoter; 3) post-translational acetylation of histones and of non-histone proteins (following treatment with deacetylase inhibitors [HDACi]), which induces viral transcription and nuc-1 remodeling. Recently, we have identified a new regulatory link between the first (NF-kB) and the third (protein acetylation) element by demonstrating a strong synergistic activation of HIV-1 promoter activity by TNFalpha (an inducer of NF-kB) and HDACi. In addition to the prototypical subtype B promoter, we have observed the TNFalpha/HDACi synergism with viral promoters from subtypes A through G of the HIV-1 major group, with a positive correlation between the number of kB sites present in the respective promoters and the amplitude of the TNFalpha/HDACi synergism. Importantly, the physiological relevance of this synergism was shown on HIV-1 replication in both acutely and latently HIV-infected cell lines. Therefore, our results open new therapeutic strategies aimed at administrating deacetylase inhibitor(s) together with continuous ART in order to force viral expression and decrease the pool of latently HIV-infected cellular reservoirs.

Fetal and neonatal cerebral infarcts.

Focal arterial infarction in the full-term newborn is an important cause of acquired cerebral lesions in the perinatal period. Clinical motor seizures, most often unifocal, are the nearly constant disclosing symptom confirmed by focal EEG abnormalities. A multifactorial physiopathology is usual, including genetic and perinatal environmental factors. In the past decade, various acquired or genetic thrombophilias have been discussed as risk factors. For several of the involved mechanisms, the excitotoxic cascade could represent a common final pathway leading to neuronal cell death. Early magnetic resonance imaging studies and EEG help to identify the newborns with strokes who are likely to develop hemiplegia and disabilities at school. Protection of the human fetal brain remains difficult, since the triggering factor initiating the excitotoxic cascade is rarely observed. Treatment of seizures is nevertheless necessary, because it seems that they accelerate anoxia-induced neuronal death in animal models of focal hypoxic ischemia.

[MRI of the brain in the evaluation of children with developmental delay]. / Apport de l'IRM cérébrale à l'exploration des retards psychomoteurs de l'enfant.

PURPOSE: To analyze the diagnostic value of MRI in children with developmental delay. Materials and Methods. From 1991 to 1997, 224 examinations were performed. Retrospective analysis of clinical findings and diagnostic yield was carried out. RESULTS: MRI was abnormal in 109 cases. It never resulted in any patient care modification. 55 malformations, 12 cases of cerebral atrophy, 7 cases of white matter disease and 2 patients with phakomatose were identified. Myelination delay (26 cases), increased signal of posterior white matter on T2-weighted images (9 cases) or widened Virchow-Robin spaces (3 cases) were frequently encountered, but it remained unclear whether they represented normal variants or true abnormalities. Post ischemic lesions were identified in 10 cases. Frequency of abnormal studies was significantly lower in children with developmental delay and behavioral disorders than in patients with other clinical presentation. CONCLUSION: Diagnostic yield of cerebral MRI can justify its performance by comparison to other imaging modalities. It should be correlated with other investigations performed in a specialized unit. Its main interest is for classification and research. Risk of sedation or anesthesia should also be taken in account. Risk can be lowered using adequately equipped MR units and organizing procedures in collaboration with anesthesiologists.

HIV-1 tat transcriptional activity is regulated by acetylation.

The human immunodeficiency virus (HIV) trans- activator protein, Tat, stimulates transcription from the viral long-terminal repeats (LTR) through an RNA hairpin element, trans-activation responsive region (TAR). We and others have shown that trans-activator protein (Tat)-associated histone acetyltransferases (TAHs), p300 and p300/CBP-associating factor (PCAF), assist functionally in the activation of chromosomally integrated HIV-1 LTR. Here, we show that p300 and PCAF also directly acetylate Tat. We defined two sites of acetylation located in different functional domains of Tat. p300 acetylated Lys50 in the TAR RNA binding domain, while PCAF acetylated Lys28 in the activation domain of Tat. In support of a functional role for acetylation in vivo, histone deacetylase inhibitor (trichostatin A) synergized with Tat in transcriptional activation of the HIV-1 LTR. Synergism was TAR-dependent and required the intact presence of both Lys28 and Lys50. Mechanistically, acetylation at Lys28 by PCAF enhanced Tat binding to the Tat-associated kinase, CDK9/P-TEFb, while acetylation by p300 at Lys50 of Tat promoted the dissociation of Tat from TAR RNA that occurs during early transcription elongation. These data suggest that acetylation of Tat regulates two discrete and functionally critical steps in transcription, binding to an RNAP II CTD-kinase and release of Tat from TAR RNA.

[Recurrence of herpes simplex encephalitis]. / Rechute d'encéphalite herpétique.

UNLABELLED: Herpes simplex encephalitis (HSE) rarely occurs in children, is not easily diagnosed, and has a poor prognosis. CASE REPORT: We report a pediatric case with a relapse on the 29th day despite conventional acyclovir therapy. As the relapse mechanism is not clearly understood, antiviral and immunosuppressive therapy was administered. CONCLUSION: This case underlines the importance of clinical examination and the necessity of accurate testing prior stopping antiviral treatment. A better understanding of the relapse mechanism is required in order to propose more efficient treatment.

[Localized neonatal convulsions and cerebral arterial infarction]. / Convulsions néonatales focalisées et infarctus artériel cérébral.

BACKGROUND: Stroke is a rare cause of neonatal seizures. CASE REPORTS: During a 5-year period, eight full-term infants were admitted to hospital for seizures due to a stroke. Seizures began shortly after birth and were always one-sided. Early CT scans showed cerebral infarctions. Motor disabilities such as hemiparesis were found in three out of seven cases; language difficulties were observed in the same proportion; however all the children had not reached school age. CONCLUSION: Neonatal localized seizures may be symptomatic of a stroke and therefore justify a computerized tomography (CT) scan. Motor and cognitive sequelae require early management.

[Paraplegia due to medullary ischemia after repair of coarctation of the aorta in an infant]. / Paraplégie par ischémie médullaire après cure chirurgicale d'une coarctation de l'aorte.

UNLABELLED: Paraplegia after repair of coarctation of the aorta is uncommon. CASE REPORT: A 2-month-old boy underwent excision of the coarctation area and primary anastomosis because of persistent heart failure. Spastic paraplegia was noted some hours after surgery. Motor deficit partially improved, but bladder dysfunction appeared some months after. Medullary magnetic resonance imaging (MRI) revealed an ischemia-related narrowing of the medullary diameter. CONCLUSION: Paraplegia after repair of coarctation of the aorta, described in adults and infants, is also seen in neonates. Prevention by preoperative monitoring of somatosensory evoked potentials is effective in adults, but difficult to perform in very young children.

An interferon regulatory factor binding site in the U5 region of the bovine leukemia virus long terminal repeat stimulates Tax-independent gene expression.

Bovine leukemia virus (BLV) replication is controlled by both cis- and trans-acting elements. The virus-encoded transactivator, Tax, is necessary for efficient transcription from the BLV promoter, although it is not present during the early stages of infection. Therefore, sequences that control Tax-independent transcription must play an important role in the initiation of viral gene expression. This study demonstrates that the R-U5 sequence of BLV stimulates Tax-independent reporter gene expression directed by the BLV promoter. R-U5 was also stimulatory when inserted immediately downstream from the transcription initiation site of a heterologous promoter. Progressive deletion analysis of this region revealed that a 46-bp element corresponding to the 5' half of U5 is principally responsible for the stimulation. This element exhibited enhancer activity when inserted upstream or downstream from the herpes simplex virus thymidine kinase promoter. This enhancer contains a binding site for the interferon regulatory factors IRF-1 and IRF-2. A 3-bp mutation that destroys the IRF recognition site caused a twofold decrease in Tax-independent BLV long terminal repeat-driven gene expression. These observations suggest that the IRF binding site in the U5 region of BLV plays a role in the initiation of virus replication.

[Antineoplastic chemotherapy and Wernicke's encephalopathy]. / Chimiothérapie anticancéreuse et encéphalopathie de Gayet-Wernicke.

BACKGROUND: Wernicke's encephalopathy is usually seen in alcoholic adults. It is rare in childhood and usually discovered in a context of several pathological events. We report here a typical case of a teenager. CASE REPORT: A 15-year-old girl with acute leukemia was given chemotherapy that resulted in profound aplasia and serious infection. She exhibited abnormal eye movements, ataxia, lethargy, enuresis and amnesia. MR examination showed T2-weighted images with increased signal in the thalami (pulvinar) and periaqueducal region. The symptoms improved dramatically with thiamine therapy. Omission of the usual vitamin supplementation between the courses of chemotherapy was responsible for this encephalopathy. CONCLUSION: Thiamine deficiency can lead to death or amnesia. Rapid efficacy of vitamin supplementation helps diagnosis and prevents sequelae.

[Actimetry: simplified analysis of wake-sleep rhythms in the newborn. Preliminary results]. / Actimétrie: analyse simplifiée des rythmes veille-sommeil chez le nouveau-né. Résultats préliminaires.

Actimetry in newborns is relevant if two actimeters are placed, one on each ankle. This study has been conducted on nine normal three days old newborns. It has shown an indisputable link between the lack of activity and the observed sleep during the night that was missing during the day. The longest period of wake was recorded during the day and the longest period of sleep or inactivity was during the night. This study has confirmed the existence of an ultradian rhythm of quiet sleep and wake. It is also possible that a beginning of a circadian rest-activity rhythm exists already in the neonatal period, that is still discussed in the literature.

Syngeneic adoptive transfer of anti-human immunodeficiency virus (HIV-1)-primed lymphocytes from a vaccinated HIV-seronegative individual to his HIV-1-infected identical twin.

Immunotherapy by adoptive transfer of lymphocytes was attempted in identical twins, one who was virus-free and the other who was infected with human immunodeficiency virus-1 (HIV-1), at the stage of acquired immunodeficiency syndrome. The noninfected twin was vaccinated by priming with a recombinant vaccinia virus expressing the envelope glycoprotein of one of his brother's viruses and boosting with the same purified gp160 adsorbed on alum. Vaccination elicited major histocompatibility complex class I-restricted CD8+ cytolytic T lymphocytes specific for HIV-1, but no antibody response. The diseased brother, a 38-year-old homosexual who had developed repeated opportunistic infections since 1990 and had a CD4+ count reduced to practically zero, was treated by infusions of lymphocytes collected from the vaccinated brother by lymphopheresis. After a first transfer of the whole lymphocyte population, no changes were observed in the clinical status and biologic or virologic parameters. A second transfer was then applied with activation of the cells with purified envelope glycoprotein before infusion. The outcome of the treatment was an increase in total lymphocytes, in CD4+ and activated CD8+ DR+ cell counts, and in proliferative responses to HIV antigens. A marked but transient 3-log increase in cellular and plasmatic virus loads was also observed after the second adoptive transfer. These observations will be considered with attention to improve the future adoptive transfer protocols, especially in patients with severe CD4+ depletion.

Ontogeny of surfactant proteins and lipid-synthesizing enzymes in cultured fetal lung epithelial cells.

Fetal rat lung epithelial cells were isolated on gestational day 17 (term is 22), separated from fibroblasts, and cultured up to 6 days in a serum-free medium on a basement membrane matrix. Surfactant protein (SP) A, barely detectable by immunostaining at the beginning of the culture, considerably increased in cells and subsequently in the lumen of the epithelial cell clusters. SP-A mRNA, already detectable at culture initiation, progressively increased. By contrast, SP-B and its mRNA appeared after 2-3 days. SP-C mRNA appeared only after 4 days of culture. Cells cultured 6 days had a phospholipid composition similar to that of freshly isolated adult rat type II cells. The enhancement of lipid synthesis between the first and the sixth culture days, reported earlier to occur in these cells, was found to be accompanied by a two- to fivefold increase in amount of mRNAs of lipogenic enzymes and choline phosphate cytidylyltransferase. In conclusion, alveolar epithelial type II cells appear to be capable of full differentiation in vitro, and components of the surfactant system are all regulated developmentally at a pretranslational level.