Stand up to better pay attention, sit down to better subtract: a new perspective on the advantage of cognitive-motor interactions

The Stroop task and subtraction rely on the different cognitive processes and cerebral regions, but both these cognitive functions interact with posture. The study of cognitive-motor interactions falls under the concept of sharing resources, implying that resources for processing are limited. Researchers try to understand this interaction by constructing dual task (DT) paradigms. None have investigated the Stroop and subtraction tasks in three inherently simple postures in two groups of young adults. This study aimed to test whether a given posture benefits a given cognitive function when cognitive and postural tasks are not overly demanding and are underpinned by common cerebral structures. This study presents the results of 60 healthy young adults performing a subtraction task in three postures (sitting, standing, and walking) and 57 healthy young adults performing the Stroop task in the same three postures. Our results showed that performance at the Stroop task, in terms of number of correct answers and interference, are better while standing or even walking compared to sitting while subtraction is better sitting compared to standing and walking. Moreover, static postural parameters did not vary when in DT compared to single task. This means that there was no additional cost on posture when achieving the cognitive activity simultaneously. The absence of impact of the DT on postural parameters in static postures and the changes in the gait pace when walking suggest that cognitive tasks can be achieved in various postures, without being too costly on posture.

Down syndrome regression disorder, a case series: Clinical characterization and therapeutic approaches

Down syndrome (DS) is one of the most frequent genetic disorders and represents the first cause of intellectual disability of genetic origin. While the majority of patients with DS follow a harmonious evolution, an unusual neurodevelopmental regression may occur, distinct from that described in the context of autism spectrum disorders, called down syndrome regression disorder (DSRD). Based on four patients, two males and two females, with age range between 20 and 24, treated at the Reference Center for Rare Psychiatric Disorders of the GHU Paris Psychiatry and Neurosciences [Pôle hospitalo-universitaire d'Évaluation Prévention et Innovation Thérapeutique (PEPIT)], we describe this syndrome, discuss its etiologies and propose therapeutic strategies. DSRD often occurs in late adolescence. There is a sudden onset of language disorders, loss of autonomy and daily living skills, as well as behavioral symptoms such as depression, psychosis, or catatonia. These symptoms are non-specific and lead to an overlap with other diagnostic categories, thus complicating diagnosis. The etiologies of the syndrome are not clearly identified but certain predispositions of patients with trisomy 21 have suggested an underlying immune-mediated mechanism. Symptomatic therapeutic approaches (serotonergic antidepressants, atypical antipsychotics, benzodiazepines) were not effective, and generally associated with poor tolerance. Etiological treatments, including anti-inflammatory drugs and corticosteroids, led to partial or good recovery in the four cases. Early recognition of regressive symptoms and rapid implementation of adapted treatments are required to improve the quality of life of patients and their families.

Assessment of arterial damage in vascular Ehlers-Danlos syndrome: a retrospective multicentric cohort

Background

Vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited connective tissue disorder due to pathogenic variants in the COL3A1 gene, leading to medium-size artery (MSA) dissection, aneurysm, and rupture with a poor prognosis. Conversely, aortic lesions are rarer and less investigated.

Purpose

To describe the association between the distribution of MSA and aortic lesions and the type of COL3A1 variants in a multicentric cohort of vEDS patients.

Methods

Analysis of the 330 vEDS adult patients from the French RaDiCO SEDVASC registry. At the time of the study, 87% were alive, 60.3% were index cases and 60.0% females. Median age at molecular diagnosis was 36 years (IQR 24.3–46.8). COL3A1 variants were identified using NGS and/or Sanger sequencing and classified according to their functional consequences: 80.6% dominant-negative (DN) and 19.4% leading to haplo-insufficiency (HI). Computed tomography angiography (CTA) was systematically performed during the initial work-up of patients. Carotid mechanics was also assessed by echotracking in a subgroup of 133 patients.

Results

Arterial lesion history was reported in 82.4% of the patients (N=272), with 227/272 patients (83.5%) having MSA lesions alone, 9 (3.3%) aortic lesions alone and 36 (13.2%) both. DN variant was associated with higher prevalence of arterial lesions than HI variant (P 0.044), especially on supra-aortic trunks and renal arteries (P 0.018 and P 0.0003 respectively). Importantly, the higher prevalence of aortic lesions observed in HI patients with arterial lesions versus DN patients (P 0.027) was not significantly different when adjusted for age (P 0.559). Carotid Young's modulus was lower in DN than HI patients (P 0.014), in association with the higher incidence of MSA lesions in this genotype group.

Conclusion

The prevalence of aortic lesions is not influenced by the COL3A1 genotype when adjusted for age. vEDS patients with DN variants have a higher frequency of MSA lesions especially in supra-aortic trunks which is associated with a lower carotid stiffness, suggesting a need for an optimal care for this subgroup of patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): French National Research Agency under the specific programme “Investments for the Future”, cohort grant-agreement ANR-l0-COHO-03-01

From neglect to earlier diagnosis: a qualitative meta-synthesis of psycho-social factors associated with consultation delay in advanced basal cell carcinoma

Local malignant potential of basal cell carcinoma (BCC) can lead at advanced stages to the destruction of underlying tissues and significant morbidity. The primary risk factor for progression of advanced basal cell carcinoma (aBCC) is the long duration of the tumour, which results from delay in seeking medical care. To assess the implication of psycho-social factors in the delay before the first medical consultation among patients with aBCC, in order to identify potentially targetable factors enabling earlier diagnosis. Three-step qualitative meta-synthesis: (1) systematic review of the literature; (2) structured qualitative analysis of these documents; (3) construction of a logical model. After screening, 81 articles were included. Self-neglect and denial in patients are roundly put forward as the main obstacles to consultation. We found that avoidance behaviour, mistaken interpretation and banalisation of symptoms, and fear of treatment all played a role. The strongest motivation to seek help comes from the realisation that new symptoms may be dangerous; the role of interpersonal surroundings is highlighted as helpful. Patient delay has multifactorial origins in aBCC, especially self-neglect ranging from denial of tumours to conscious refusal of treatment.

Pseudoxanthoma elasticum overlaps hereditary spastic paraplegia type 56

PURPOSE

Pseudoxanthoma elasticum (PXE) is a recessive disorder involving skin, eyes and arteries, mainly caused by ABCC6 pathogenic variants. However, almost one fifth of patients remain genetically unsolved despite extensive genetic screening of ABCC6, as illustrated in a large French PXE series of 220 cases. We searched for new PXE gene(s) to solve the ABCC6-negative patients.

METHODS

First, family-based exome sequencing was performed, in one ABCC6-negative PXE patient with additional neurological features, and her relatives. CYP2U1, involved in hereditary spastic paraplegia type 56 (SPG56), was selected based on this complex phenotype, and the presence of two candidate variants. Second, CYP2U1 sequencing was performed in a retrospective series of 46 additional ABCC6-negative PXE probands. Third, six additional SPG56 patients were evaluated for PXE skin and eye phenotype. Additionally, plasma pyrophosphate dosage and functional analyses were performed in some of these patients.

RESULTS

6.4% of ABCC6-negative PXE patients (n = 3) harboured biallelic pathogenic variants in CYP2U1. PXE skin lesions with histological confirmation, eye lesions including maculopathy or angioid streaks, and various neurological symptoms were present. CYP2U1 missense variants were confirmed to impair protein function. Plasma pyrophosphate levels were normal. Two SPG56 patients (33%) presented some phenotypic overlap with PXE.

CONCLUSION

CYP2U1 pathogenic variants are found in unsolved PXE patients with neurological findings, including spastic paraplegia, expanding the SPG56 phenotype and highlighting its overlap with PXE. The pathophysiology of ABCC6 and CYP2U1 should be explored to explain their respective role and potential interaction in ectopic mineralization.

Epigenetics in bipolar disorder: a critical review of the literature

INTRODUCTION

Bipolar disorder (BD) is a chronic, disabling disease characterised by alternate mood episodes, switching through depressive and manic/hypomanic phases. Mood stabilizers, in particular lithium salts, constitute the cornerstone of the treatment in the acute phase as well as for the prevention of recurrences. The pathophysiology of BD and the mechanisms of action of mood stabilizers remain largely unknown but several pieces of evidence point to gene x environment interactions. Epigenetics, defined as the regulation of gene expression without genetic changes, could be the molecular substrate of these interactions. In this literature review, we summarize the main epigenetic findings associated with BD and response to mood stabilizers.

METHODS

We searched PubMed, and Embase databases and classified the articles depending on the epigenetic mechanisms (DNA methylation, histone modifications and non-coding RNAs).

RESULTS

We present the different epigenetic modifications associated with BD or with mood-stabilizers. The major reported mechanisms were DNA methylation, histone methylation and acetylation, and non-coding RNAs. Overall, the assessments are poorly harmonized and the results are more limited than in other psychiatric disorders (e.g. schizophrenia). However, the nature of BD and its treatment offer excellent opportunities for epigenetic research: clear impact of environmental factors, clinical variation between manic or depressive episodes resulting in possible identification of state and traits biomarkers, documented impact of mood-stabilizers on the epigenome.

CONCLUSION

Epigenetic is a growing and promising field in BD that may shed light on its pathophysiology or be useful as biomarkers of response to mood-stabilizer.

Simple Method for Quantifying Alpha-Tocopherol in Low-Density+Very-Low-Density Lipoproteins and in High-Density Lipoproteins

We assessed the distribution of alpha-tocopherol in serum lipoprotein samples after separating the lipoprotein fractions by either sequential ultracentrifugation or selective precipitation with sodium phosphotungstate-magnesium chloride reagent. alpha-Tocopherol concentrations were determined by reversed-phase high-performance liquid chromatography. After ultracentrifugation, we found that in men, low- and very-low-density serum lipoproteins (LDL-VLDL) contained 53.6% of alpha-tocopherol vs 46.4% in high-density lipoproteins (HDL). In women, serum LDL-VLDL contained 45.6% alpha-tocopherol after ultracentrifugation vs 54.4% in HDL. After selective precipitation, the proportions of alpha-tocopherol in men were 56.1% in LDL-VLDL vs 43.9% in HDL, and in women, 45.4% in LDL-VLDL vs 54.6% in HDL. After selective precipitation, alpha-tocopherol recovery from whole lipoprotein fractions was 97% to 100% vs 80% after ultracentrifugation, thus allowing more accurate alpha-tocopherol quantification than after separation by ultracentrifugation.

Socio-economics status and metabolic syndrome: A meta-analysis

OBJECTIVE

The metabolic syndrome (MetS) is responsible for an increased risk of type 2 diabetes, cardiovascular diseases and is associated with all-cause and cardiovascular mortality. Economic and social vulnerability is not an easy concept to grasp, but some studies investigate the association between MetS and socioeconomic and demographic factors, deprivation (more often correlations rather than causal one due to data). This work aims to assess the association between MetS and socio-economic gradient (SEG) in the literature by performing a meta-analysis.

DESIGN

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement for systematic reviews were followed.

SETTING

The raw list of studies extracted from PubMed as regard to the inclusion/exclusion criteria was imported in Word. Studies were filed with regard to our three definitions of SEG and their title.

PARTICIPANTS

Subgroup analysis were performed considering several definitions of Mets: NCEP-ATPIII and IDF2006.

RESULTS

The overall multivariable-adjusted OR showed that the risk of MetS was significantly increased in association with SEG The results of the subgroup analysis showed an increased risk of MetS in association with SEG when IDF definition was considered.

CONCLUSIONS

Targeted interventions must be implemented in a specific way as prevention campaigns aimed at the general population are generally not adapted to this particular vulnerable population.

Improving image quality of mid-trimester fetal sonography in obese women: role of ultrasound propagation velocity

OBJECTIVE

The quality of ultrasound images is impaired in obese patients. All ultrasound scanners are calibrated for an ultrasound propagation velocity of 1540 m/s, but the propagation in fatty tissue is slower (in the order of 1450 m/s). The main objective of this study was to evaluate the quality of images obtained with different ultrasound propagation velocity settings during the mid-trimester fetal ultrasound examination in obese patients.

METHODS

This was a cross-sectional study using image sets of four recommended scanning planes collected from 32 obese pregnant women during their mid-trimester fetal scan. Each image set comprised three images obtained successively at three different propagation velocity settings (1540 m/s, 1480 m/s and 1420 m/s). A panel of 114 experts assessed the quality of 100 image sets, grading them from A (most acceptable) to C (least acceptable). Scanning-plane-specific indicators of adiposity (fatty layer thickness, probe-to-organ distance) were analyzed for each scanning plane.

RESULTS

The experts had a mean of 18.1 ± 10.2 years of experience. The grade distribution (A, B, C) differed significantly (P < 0.0001) between the three propagation velocity settings tested; at the lower speed of 1480 m/s, images were most often graded A, while at the conventional speed of 1540 m/s, they were most often graded C. Regardless of the scanning plane, the thicker the fatty layer of the abdominal wall in a given plane, the lower the preferred speed (P < 0.0001).

CONCLUSION

The construction of images taking into account ultrasound propagation velocities lower than 1540 m/s can improve significantly the quality of images obtained during mid-trimester fetal ultrasonography in obese women. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Systematic study of the impact of MOF densification into tablets on textural and mechanical properties

Densification process of MOF powders (HKUST-1, UiO-66, UiO-66-NH₂, and UiO-67) into mechanically resistant pellets with maintained microporosity and enhanced volumetric uptake.

[Treatment of stable COPD : GOLD 2017 and the associations…]

GOLD 2017 Report highlights the importance of patient symptoms and exacerbation risks in influencing some therapeutic decisions for individualized patient care. Assessment of the severity of airway obstruction is now separated from the " ABCD " groups but remains a key step for the diagnosis, prognostication and nonpharmacological therapies of COPD patients. Inhaled long-acting bronchodilators, alone or in combination, have a central role in the treatment of COPD patients. Their prolonged action allows a significant improvement not only of FEV1, but also of dyspnoea and health status. A clinically important effect was more frequently reached with LABA+LAMA combination than with either medication alone. LAMAs have a greater effect on exacerbation reduction compared to LABAs and LABA+LAMA combination reduces exacerbations compared to monotherapy or LABA+ICS combination. As regular treatment with ICS increases the risk of pneumonia, LABA+ICS combination is not a primary choice excepted in selected cortico-sensitive patients. When appropriate, withdrawal of ICS is achievable without significant harm using LABA+LAMA combination. Studies determining the precise place of LABA+LAMA+ICS combination in the treatment strategy are underway.

Country-specific chemical signatures of persistent organic pollutants (POPs) in breast milk of French, Danish and Finnish women

The present study compares concentrations and chemical profiles of an extended range of persistent organic pollutants (dioxins, polychlorobiphenyls, brominated flame retardants and organochlorine pesticides) in breast milk samples from French (n = 96), Danish (n = 438) and Finnish (n = 22) women. Median exposure levels observed in French women (WHO-TEQ₂₀₀₅ PCDD/F = 6.1 pg/g l.w., WHO-TEQ₂₀₀₅ dl-PCB = 4.3 pg/g l.w., sum of 6 ndl-PCB = 85.2 ng/g l.w., sum of 7 i-PBDE = 1.5 ng/g l.w.) appeared overall lower than in Danish and Finnish women for all examined POPs, except for α-HBCD (2-fold higher level at 0.6 ng/g l.w.). Furthermore, the observed exposure levels of dioxins and PCBs were higher in Danish women (WHO-TEQ₂₀₀₅ PCDD/F = 13.2 pg/g l.w., WHO-TEQ₂₀₀₅ dl-PCB = 6.6 pg/g l.w., sum of 6 ndl-PCB = 162.8 ng/g l.w.) compared to Finnish women (WHO-TEQ₂₀₀₅ PCDD/F = 9.0 pg/g l.w., WHO-TEQ₂₀₀₅ dl-PCB = 4.6 pg/g l.w., sum of 6 ndl-PCB = 104.0 ng/g l.w.), whereas the concentrations of PBDEs were similar for Danish and Finnish women (sum of 7 i-PBDE = 4.9 and 5.2 ng/g l.w. respectively). The organochlorine (OC) pesticide contamination profile, determined in a subset of French samples, was dominated by p,p'-DDE (56.6%), followed by β-HCH (14.2%), HCB (9.7%) and dieldrin (5.2%), while other compounds were only minor contributors (<5%). The three countries appeared to be discriminated by the observed contamination patterns of the PCDD/F versus PCB, and the 1,2,3,6,7,8-HxCDD versus 1,2,3,4,7,8-HxCDD ratios, in addition to the relative contributions of specific congeners to the contamination profile (PCBs #118 and #156, PBDEs #28, #47, #99 and #153). In conclusion, unique chemical signatures were observed for each country on the basis of some POP congeners. Future biomonitoring studies will need to consider the high variability of individual exposure profiles in relation to multiple exposure sources but also physiological and metabolic differences.

Phenotypic variability and diffuse arterial lesions in a family with Loeys-Dietz syndrome type 4

Syndromic thoracic aortic aneurysm and dissection (TAAD) can suggest Marfan, vascular Ehlers-Danlos or Loeys-Dietz (LDS) syndromes. Several of the TGFβ-pathway-related genes predispose to different types of LDS. Heterozygous loss-of-function variations in TGFβ2 have been shown to be responsible for a novel form of syndromic TAAD associated with an impairment of the mitral valve and cerebrovascular disease called Loeys-Dietz syndrome type 4 (LDS4). We report the clinical characterization of a LDS4 French family with sudden deaths and diffuse vascular lesions, caused by a frameshift mutation in TGFβ2 gene: c.[995del]; p.(Leu332TrpfsTer27). Clinical characteristics include aneurysm of aortic sinus, skeletal and cutaneous features compatible with a syndromic form of TAAD (joint hypermobility, scoliosis, and easy bruises), intracranial aneurysms and rare mitral valve involvement. Iliac aneurysms, systemic medium caliber arteries dissections, and mild developmental delay were present in the family, and have not been described in LDS4. Phenotypic variability was also an important finding, including absence of clinical vascular events at advanced age in one case. Our data expand the phenotype of LDS4: we confirm that TGFβ2 mutations are responsible for true LDS syndrome with non-specific features of connective tissue disorders and diffuse vascular lesions. Adapted vascular follow up and prevention has to be proposed for these patients.

Electron transfers in a TiO2-containing MOR zeolite: synthesis of the nanoassemblies and application using a probe chromophore molecule

New assemblies constituted by a microporous matrix of mordenite (MOR) zeolite on which TiO2 nanoclusters are deposited were synthesized using ionic oxalate complexes and TiCl3 titanium precursors. The samples were used to investigate the transfer of electrons produced by spontaneous or photo-induced ionization of a guest molecule (t-stilbene, t-St) occluded in the porous volume towards the conduction band of a conductive material placed nearby, in the pores or at least close to their entrance. The reaction mechanisms were compared in these Ti-rich solids and in a Ti-free mordenite sample. The characterization by XRD, N2 physisorption, TEM, XPS and DRIFT spectroscopy of the supramolecular TiO2/MOR systems before t-St adsorption showed the preservation of the crystalline structure after Ti addition and thermal activation treatments. They also revealed that titanium is mainly located at the external surface of the zeolite grains, in the form of highly dispersed and/or aggregated anatase. After incorporation of the guest molecule in the new assemblies, diffuse reflectance UV-visible and EPR spectroscopies indicate that the electron transfer processes are similar with and without TiO2 but strongly stabilized t-St˙(+) radicals are detected in the TiO2-MOR samples whereas such species were never detected earlier in TiO2-free mordenite using these techniques. The stabilization process is found to be more efficient in the sample prepared with TiCl3 as the precursor than with titanium oxalates. It is proposed that the proximity of TiO2 with the formed t-St˙(+) radicals provokes the stabilization of the radical through capture of the ejected electron by the semi-conductor and that confinement effects can also play a role.

[Comparison of two protocols of febrile urinary tract infection management in children]

PURPOSE

To compare two first febrile urinary tract infection (UTI) management protocols with regards to the diagnosis of high-grade vesicoureteral reflux (VUR) and cost.

METHODS

This study compared two cohorts of children under 16 years of age, admitted for a first episode of febrile UTI. The first group (in 2005) was managed according to previous recommendations (IV treatment and cystography performed for all children under 3 years of age). The second group (in 2006) was managed according to age and procalcitonin level. High-grade VUR frequency, UTI recurrence, hospitalization rate, and cost were compared between the two cohorts.

RESULTS

A total of 225 children were included in 2005 and 116 in 2006. High-grade VUR was found in 6.2 and 9.5% of the patients in 2005 and 2006, respectively (P=0.274). There was no statistically significant difference in the UTI recurrence rate between the two cohorts (5.3% in 2005 and 8.6% in 2006; P=0.237). The mean cost of an episode of febrile UTI was not significantly different in 2005 and 2006 (€2235 in 2005, €2256 in 2006; P=0.902), but was lower for children older than 6 months in 2006 (€1292 versus €1882 in 2005; P=0.0042).

CONCLUSION

Our management protocol for a first febrile UTI episode in children based on procalcitonin levels seems to be suitable for the diagnosis of high-grade VUR. The hospitalization rate and the mean cost of management for children older than 6 months of age was significantly reduced in 2006. The management guidelines for a first occurrence of febrile UTI in children should be reconsidered.

Liposomes for gene transfer and expression in vivo

A recombinant plasmid encoding rat preproinsulin I was encapsulated in large liposomes and injected intravenously into rats. Glycaemia and blood, splenic and hepatic insulin were assayed from 6 h after inoculation. Control animals received (i) empty liposomes, (ii) liposomes carrying the Escherichia coli pBR 322 plasmid, (iii) the free rat insulin I gene, or (iv) no injection. All controls showed unchanged glucose and insulin levels. Six hours after inoculation the treated rats had 72 +/- 5 mg glucose/100 ml of blood, compared with 107 +/- 2 mg/ml for controls. Radioimmunoassay of blood insulin gave 61 +/- 8 microunits/ml (43 +/- 5 microunits/ml for controls). Spleen and liver values were 242 +/- 22 and 204 +/- 20 microunits/g of tissue, respectively (112 +/- 20 and 87 +/- 15 microunits/g in controls). The kinetics and extent of uptake of liposomes by spleen and liver were studied by external gamma-camera imaging after injection of 111In-labelled liposomes. The results paralleled insulin synthesis in the two organs. The insulin gene was localized in liver cells after injection of liposomes containing the plasmid encoding the gene. Livers were processed 4 h after inoculation for isolation of hepatocytes, Kupffer cells and endothelial cells. DNA was purified and exogenous DNA detected by Southern blotting. Kupffer cells were the primary target for gene incorporation with liposomes consisting of phospholipids and cholesterol. Targeting of liposomes to other liver cells was attempted by including lactosylceramide in the liposomes. This increased the amount of the exogenous gene in hepatocytes and particularly in endothelial cells. The efficiency of liposome-mediated gene transfer in vivo is high, since a few per cent of the transferred DNA is taken up by the liver cells and detected.

Two silent substitutions in the PDHA1 gene cause exon 5 skipping by disruption of a putative exonic splicing enhancer

BACKGROUND

Synonymous mutations within exons may cause aberrant splicing by disrupting exonic splicing enhancer (ESE) motifs in the vicinity of non consensus splice sites. Mutational analysis of PDHA1 revealed only one silent single nucleotide substitution in exon 5 in two unrelated boys and a girl (c.483C>T and c.498C>T variants, respectively). For both patients, pyruvate dehydrogenase complex activity was low and the immunoreactive E1alpha protein was defective in cultured fibroblasts.

METHODS AND RESULTS

One of the boys was a somatic mosaic for the c.483C>T variant, as shown by the variable ratio of mutant to normal alleles in fibroblast, lymphocyte and single hair root DNA. Transcript analysis in fibroblasts from the three patients revealed the presence of both normal and truncated cDNAs, with the splicing out of exon 5 predicted to result in a frame shift and premature termination (p.Arg141AlafsX11). The treatment of fibroblasts with emetine before harvesting to prevent nonsense mRNA-mediated decay increased the amount of mutant mRNA. In silico analysis revealed that each variant disrupted a putative SRp55 binding site and that the intron 5 donor splice site (5'ss) contained a weak splicing signal. Transient transfection of COS-7 or Hela cells with hybrid minigene constructs containing wild-type or mutant PDHA1 exon 5, followed by RT-PCR demonstrated that each variant resulted in the incomplete inclusion of PDHA1 exon 5, and that this defect was corrected following the restoration of a perfect consensus sequence for the 5' splice site by site-directed mutagenesis.

CONCLUSION

These two synonymous mutations expand the spectrum of rare PDHA1 splicing mutations, all of which are located in non canonical splice sites.

Beclin 1 mRNA strongly correlates with Bcl-XLmRNA expression in human hepatocellular carcinoma

Beclin 1 physically associates with Bcl-x(L) and is considered as a haploinsufficient tumor suppressor. As the role of Beclin 1 in hepatocellular carcinoma (HCC) is unknown, we determined Beclin 1 mRNA expression in 27 pairs of tumoral/nontumoral (T/NT) liver samples. The Beclin 1 mRNA T/NT ratio was less than 0.5 in 2 tumors and more than 2 in 1 tumor, and was positively correlated with the Bcl-X(L) mRNA T/NT ratio (P < 0.001), but not with the proliferating cell nuclear antigen mRNA T/NT ratio. Coregulation of Beclin 1 and Bcl-X(L) expression in HCC may suggest cooperation in the regulation of apoptosis.

Oxidative stress implication in a new phenotype of amyotrophic quadricipital syndrome with cardiac involvement due to lamin A/C mutation

This study aimed at evaluating OS in an amyotrophic quadricipital syndrome with cardiac impairment in a family of 80 members with a mutation in lamin A/C gene. Twelve patients had cardiac involvement (5 cardiac and skeletal muscles impairment). OS was evaluated in blood samples (thiobarbituric acid-reactive substances (TBARS), carbonylated proteins (PCO)) 6 "affected patients" with phenotypic and genotypic abnormalities without heart failure and 3 "healthy carrier" patients. OS was higher in affected patients than in healthy, as shown by the higher TBARS and PCO values. Patients with cardiac and peripheral myopathy exhibited a higher OS than patients with only cardiac disease (TBARS: 1.73 +/- 0.05 vs. 1.51 +/- 0.04 mmol/l (p = 0.051), PCO: 2.73 +/- 0.34 vs. 0.90 +/- 0.10 nmol/mg protein (p = 0.47)), and with healthy carriers patients (TBARS: 1.73 +/- 0.05 vs. 1.16 +/- 0.14 mmol/l (p = 0.05), PCO: 2.73 +/- 0.34 vs. 0.90 +/- 0.20 nmol/mg protein (p = 0.47)). OS may thus contribute to the degenerative process of this laminopathy. ROS production occurs, prior to heart failure symptoms. We suggest that the extent activation may also promote the variable phenotypic expression of the disease.

L'entropie: un moyen d'apprécier le défaut d'analgésie?

OBJECTIVE

Comparison between BIS (Bispectral Index) and state (SE) and response (RE) entropy during laparotomy for inflammatory bowel disease patients (IBD) and evaluation of the variations of RE and SE during nociceptive stimulation.

STUDY DESIGN

Prospective, observational study.

PATIENTS AND METHODS

Fourteen IBD's patients undergoing laparotomy were included. Anaesthesia aimed to maintain BIS between 40 and 60 by isoflurane and nitrous oxide. Analgesia was performed by sufentanil bolus administrated according to an increase of 20% of systolic blood pressure (SBP) and heart rate compared with the baseline values. BIS, RE and SE were measured at each nociceptive stimulation. A variance analysis (Anova) was used to assess BIS, RE and SE variations throughout surgery (p<0.05 as significant). Relationship between BIS, RE and SE was assessed by Pearson correlation (p<0.01 as significant). The ability for SE and RE to predict depth of anaesthesia and intraoperative analgesia was performed by calculating area under the receiver operated curves (AUC).

RESULTS

BIS and entropy parameters had strictly the same evolution during anaesthesia. SBP increased significantly during nociceptive stimulation while no variation of RE was observed. A significant correlation was shown between BIS, RE and SE. The evaluation of anaesthesia depth was good for RE (AUC: 0.932+/-0.26) and SE (AUC: 0.926+/-0.27). There was however no difference between RE and SE to predict analgesic requirement.

CONCLUSION

Because RE includes muscular frequency analysis, it does not allow analgesic requirement evaluation in paralyzed patients.

[Cellular sources of reactive oxygen and nitrogen species. Roles in signal transcription pathways]

The history of studies regarding reactive oxygen and nitrogen species (ROS/RNS) is approximatively of 50 years. ROS were shown initially for their deleterious effects on marcormolecules such as DNA and proteins, leading to deterioration of cellular functions as an oxidative stress. On the other hand, recent studies have demonstrated that ROS/RNS act as oxidative signalling in cells, resulting in various gene expressions. This brief review focuses on the main cellular origins of ERO/ERN, such as mitochondrial respiratory chain, NAD(P)H oxidase and NO synthases, and describe the modulation by the reactive species of two major signal transduction pathways, NF-KB and AP-1 pathways.

Metformin reduces angiotensin-mediated intracellular production of reactive oxygen species in endothelial cells through the inhibition of protein kinase C

Oxidative stress plays a major role in the pathogenesis and in the onset of macrovascular complications of diabetes. We previously reported that the antihyperglycaemic drug metformin was able to decrease significantly intracellular reactive oxygen species (ROS) production of bovine aortic endothelial cells (BAEC) activated by high levels of glucose and angiotensin II (ANG). The aim of the present study was to investigate whether the antioxidant effect of metformin on BAEC could be mediated through a modulation of protein kinase C (PKC) activity, which plays a key role in the pathophysiology of diabetes. The effects of metformin on intracellular ROS production, PKC translocation and activity were studied on endothelial cells stimulated by PMA (a direct PKC activator), ANG or high levels of glucose as pathophysiological stimuli of endothelial dysfunction in diabetes. We showed that metformin decreased ROS production on PMA-, ANG- and glucose-stimulated BAEC in a similar manner to that obtained by PKC specific inhibitors (calphostin C, chelerythrine) alone. On the other hand, metformin reduced both PKC membrane translocation and kinase activity in ANG-stimulated cells. In PMA-activated cells, metformin reduced membrane PKC activity but we did not observe any alteration of PKC membrane translocation. Finally, in vitro incubation with purified PKC indicated that metformin had no direct effect on PKC activity. Taken together, our results suggest that metformin exerted intracellular antioxidant properties by decreasing ROS production through the inhibition of PKC activity.

First characterization of a large deletion of the PDHA 1 gene

Pyruvate dehydrogenase complex (PDC) deficiency is one of the major recognized causes of congenital lactic acidosis. The most common form is due to PDHA 1 gene (Xp22.12) defects. Here, we report the case of a Polynesian girl presenting with delayed neurological development, cortical atrophy, and posterior corpus callosum agenesis. Elevated lactate and pyruvate levels in blood and cerebrospinal fluid suggested PDC deficiency. However, PDC activity was within the normal range in lymphocytes and the direct sequencing of the 11 exons and intron-exon junctions of the PDHA 1 gene did not show any changes. Long-range PCR amplification of the whole gene (16 kb) from blood DNA revealed a heterozygous deletion of approximately 4.2kb. Fine mapping of the deletion breakpoint was achieved using purified long-range PCR products for restriction enzyme analysis and direct sequencing. The deletion removed a 4,227 bp region covering part of intron 5 to part of intron 9 [g.10,145_14,371 del 4,227]. The deletion breakpoint contained a short direct repeat (GTAG), which may be derived either from the upstream or the downstream homologous sequence. The presence of a GAG triplet and inverted repeats in the vicinity of the deletion suggest replication slippage at a polymerase alpha arrest site. This is the first time that a large intragenic deletion of the PDHA 1 gene has been characterized.

Deoxyguanosine kinase mutations and combined deficiencies of the mitochondrial respiratory chain in patients with hepatic involvement

The activity of deoxyguanosine kinase (DGUOK), a mitochondrial enzyme involved in the anabolism of mitochondrial (mt) deoxyribonucleotides, governs the maintenance of the mtDNA. Deleterious mutations of the DGUOK gene are thus associated with mtDNA depletion and result in combined deficiencies of mtDNA-encoded respiratory chain enzymes. With the aim to estimate the prevalence of DGUOK mutations in a cohort of 30 patients with hepatocerebral disease and combined respiratory chain deficiencies, we studied the DGUOK gene and identified previously unreported mutations in five families. Two patients and their affected sibs, born to non-consanguineous parents, were homozygous for a missense mutation (M1T, and L250S, respectively). One patient presented a homozygous 4 pb insertion (796 insTGAT) and two other patients, and their affected sibs, were compound heterozygous (E165V/L266R and E211G/L266R, respectively). These findings allowed us to propose prenatal diagnosis in two families. In conclusion, we observed a high prevalence of DGUOK mutations (17%) in patients with hepatic involvement and combined respiratory chain deficiencies with hepatic involvement.

[Perioperative management of asplenic patients]

OBJECTIVE

In 2003, asplenia had involved 250000 patients in France. These patients are at risk of severe infection, mostly with capsulated bacteria as pneumococci, meningococci and Haemophilus. The higher mortality and morbidity due to infection in asplenic patient led in June 2003 a French expert committee to propose preventive management based on vaccination and antibioprophylaxis.

STUDY DESIGN

Update article.

DATA SYNTHESIS

For vaccination, two vaccines against pneumococci are available. The first one, the antipolysaccharide (Pneumo 23) is recommended for adults. It is effective for the majority of the serotypes even if its efficacy can be variable. The second one a conjugated pneumococcal vaccine (Prenevar) is used for children under two years because it has higher activity on antibiotic resistant strains therefore increasing antibiotic prophylaxis efficiency. When splenectomy is required, vaccination against pneumococci, Haemophilus (b type) and C meningococci must be performed at least 15 days before surgery, in order to get better immune stimulation. In case of emergency, vaccines have to be administrated within 30 days after surgery. Antibioprophylaxis is based on cefazolin injection before splenectomy and by postoperative intravenous amoxicillin administration. As soon as oral intake is allowed, antibioprophylaxis is continued for at least two years in adults and five years in children. Both antibiotic and vaccination have been reported to reduce pneumococcus infections.