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1.
Neurogastroenterol Motil ; 30(9): e13371, 2018 09.
Article in English | MEDLINE | ID: mdl-29781137

ABSTRACT

BACKGROUND: Primary chronic intestinal pseudo-obstruction (CIPO) is a rare, potentially life-threatening disorder characterized by severely impaired gastrointestinal motility. The objective of this study was to examine the contribution of ACTG2, LMOD1, MYH11, and MYLK mutations in an Australasian cohort of patients with a diagnosis of primary CIPO associated with visceral myopathy. METHODS: Pediatric and adult patients with primary CIPO and suspected visceral myopathy were recruited from across Australia and New Zealand. Sanger sequencing of the genes encoding enteric gamma-actin (ACTG2) and smooth muscle leiomodin (LMOD1) was performed on DNA from patients, and their relatives, where available. MYH11 and MYLK were screened by next-generation sequencing. KEY RESULTS: We identified heterozygous missense variants in ACTG2 in 7 of 17 families (~41%) diagnosed with CIPO and its associated conditions. We also identified a previously unpublished missense mutation (c.443C>T, p.Arg148Leu) in one family. One case presented with megacystis-microcolon-intestinal hypoperistalsis syndrome in utero with subsequent termination of pregnancy at 28 weeks' gestation. All of the substitutions identified occurred at arginine residues. No likely pathogenic variants in LMOD1, MYH11, or MYLK were identified within our cohort. CONCLUSIONS AND INFERENCES: ACTG2 mutations represent a significant underlying cause of primary CIPO with visceral myopathy and associated phenotypes in Australasian patients. Thus, ACTG2 sequencing should be considered in cases presenting with hypoperistalsis phenotypes with suspected visceral myopathy. It is likely that variants in other genes encoding enteric smooth muscle contractile proteins will contribute further to the genetic heterogeneity of hypoperistalsis phenotypes.


Subject(s)
Actins/genetics , Genetic Predisposition to Disease/genetics , Intestinal Pseudo-Obstruction/genetics , Adolescent , Adult , Australasia , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Mutation, Missense , Young Adult
2.
J Biol Chem ; 291(9): 4442-52, 2016 Feb 26.
Article in English | MEDLINE | ID: mdl-26740628

ABSTRACT

DNA damage must be repaired in an accurate and timely fashion to preserve genome stability. Cellular mechanisms preventing genome instability are crucial to human health because genome instability is considered a hallmark of cancer. Collectively referred to as the DNA damage response, conserved pathways ensure proper DNA damage recognition and repair. The function of numerous DNA damage response components is fine-tuned by posttranslational modifications, including ubiquitination. This not only involves the enzyme cascade responsible for conjugating ubiquitin to substrates but also requires enzymes that mediate directed removal of ubiquitin. Deubiquitinases remove ubiquitin from substrates to prevent degradation or to mediate signaling functions. The Saccharomyces cerevisiae deubiquitinase Ubp7 has been characterized previously as an endocytic factor. However, here we identify Ubp7 as a novel factor affecting S phase progression after hydroxyurea treatment and demonstrate an evolutionary and genetic interaction of Ubp7 with DNA damage repair pathways of homologous recombination and nucleotide excision repair. We find that deletion of UBP7 sensitizes cells to hydroxyurea and cisplatin and demonstrate that factors that stabilize replication forks are critical under these conditions. Furthermore, ubp7Δ cells exhibit an S phase progression defect upon checkpoint activation by hydroxyurea treatment. ubp7Δ mutants are epistatic to factors involved in histone maintenance and modification, and we find that a subset of Ubp7 is chromatin-associated. In summary, our results suggest that Ubp7 contributes to S phase progression by affecting the chromatin state at replication forks, and we propose histone H2B ubiquitination as a potential substrate of Ubp7.


Subject(s)
Chromatin/enzymology , Fungal Proteins/metabolism , S Phase , Saccharomycetales/enzymology , Ubiquitin-Specific Proteases/metabolism , Chromatin/drug effects , Chromatin/metabolism , Cisplatin/pharmacology , Cross-Linking Reagents/pharmacology , DNA Repair , DNA Replication/drug effects , Fungal Proteins/genetics , Gene Deletion , Genomic Instability/drug effects , Histones/metabolism , Hydroxyurea/pharmacology , Microbial Viability/drug effects , Nucleic Acid Synthesis Inhibitors/pharmacology , S Phase/drug effects , Saccharomycetales/cytology , Saccharomycetales/drug effects , Saccharomycetales/growth & development , Ubiquitin-Specific Proteases/genetics
3.
Encephale ; 41(6): 493-8, 2015 Dec.
Article in French | MEDLINE | ID: mdl-26548617

ABSTRACT

BACKGROUND: The prevalence of psychiatric disorders in epileptic patients remains unclear. OBJECTIVE: This study was conducted in order to determine the prevalence and nature of the psychiatric disorders and the associated factors in patients with idiopathic epilepsy. METHODS: A cross-sectional study was conducted over a period of eighteen months in the psychiatric unit of the University Hospital Hassan II of Fez (Morocco). A questionnaire was completed by the included patients, which specified: the socio-demographic data, personal and family history, and the clinical features of epilepsy and its management. Psychiatric disorders were identified by the Mini International Neuropsychiatric Interview test (MINI). The severity of the depression and anxiety symptoms was investigated using the Beck Depression Inventory (BDI) and the Hamilton Rating Scale. RESULTS: Eighty-nine patients met the inclusion criteria. The average age of patients was 29.7±10.8years. Mood disorders were the leading psychiatric comorbidity: 32.6% among which 25.8% of major depressive episodes, 15.7% of dysthymia and 2.2% of hypomanic episodes. Anxiety disorders came second: 28.1% (among which 19.1% panic disorder, 13.5% agoraphobia, 12.4% generalized anxiety disorder, 10.1% social phobia and 4.5% post-traumatic stress disorder). Female gender, unemployment and poor compliance to antiepileptic drugs are all risk factors for the occurrence of psychiatric disorders in this population.


Subject(s)
Anxiety Disorders/complications , Epilepsy/psychology , Mood Disorders/complications , Adult , Anxiety Disorders/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Mood Disorders/epidemiology , Morocco/epidemiology , Prevalence , Psychiatric Status Rating Scales , Risk Factors , Sex Factors , Surveys and Questionnaires , Unemployment , Young Adult
4.
Nat Commun ; 6: 7834, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26215801

ABSTRACT

The conserved budding yeast Rad51 paralogues, including Rad55, Rad57, Csm2 and Psy3 are indispensable for homologous recombination (HR)-mediated chromosome damage repair. Rad55 and Rad57 are associated in a heterodimer, while Csm2 and Psy3 form the Shu complex with Shu1 and Shu2. Here we show that Rad55 bridges an interaction between Csm2 with Rad51 and Rad52 and, using a fully reconstituted system, demonstrate that the Shu complex synergizes with Rad55-Rad57 and Rad52 to promote nucleation of Rad51 on single-stranded DNA pre-occupied by replication protein A (RPA). The csm2-F46A allele is unable to interact with Rad55, ablating the ability of the Shu complex to enhance Rad51 presynaptic filament assembly in vitro and impairing HR in vivo. Our results reveal that Rad55-Rad57, the Shu complex and Rad52 act as a functional ensemble to promote Rad51-filament assembly, which has important implications for understanding the role of the human RAD51 paralogues in Fanconi anaemia and cancer predisposition.


Subject(s)
Adenosine Triphosphatases/metabolism , DNA Repair Enzymes/metabolism , DNA, Single-Stranded/metabolism , DNA-Binding Proteins/metabolism , Rad51 Recombinase/metabolism , Rad52 DNA Repair and Recombination Protein/metabolism , Recombinational DNA Repair , Replication Protein A/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Cell Cycle Proteins/metabolism , In Vitro Techniques , Microscopy, Electron , Nuclear Proteins/metabolism , Saccharomyces cerevisiae , Schizosaccharomyces pombe Proteins/metabolism
5.
Clin Genet ; 88(6): 573-8, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25529940

ABSTRACT

An MYH2 mutation p.(Glu706Lys) was originally described in a family with autosomal dominant inheritance, where the affected family members presented with multiple congenital contractures and ophthalmoplegia, progressing to a proximal myopathy in adulthood. Another patient with a dominant mutation p.(Leu1870Pro) was described, presenting as a congenital myopathy with ophthalmoplegia. Here, we present a patient with symptoms beginning at age 16 years, of prominent distal but also proximal weakness, bulbar involvement and ophthalmoplegia. Initially, clinically classified as oculopharyngodistal myopathy, the patient was found to carry a novel, de novo MYH2 mutation c.5630T>C p.(Leu1877Pro). This expands the phenotype of dominant MYH2 myopathies with the clinical phenotype overlapping the oculopharyngodistal myopathy spectrum.


Subject(s)
Genetic Predisposition to Disease/genetics , Muscular Diseases/genetics , Mutation, Missense , Myosin Heavy Chains/genetics , Ophthalmoplegia/genetics , Amino Acid Sequence , Humans , Male , Molecular Sequence Data , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Young Adult
6.
ScientificWorldJournal ; 2014: 806252, 2014.
Article in English | MEDLINE | ID: mdl-24982998

ABSTRACT

Adsorption of Cd(2+) on two types of Egyptian soils: clay (alluvial) and sandy loam (calcareous), was studied. Effect of changing the matrix electrolyte type and concentration was used to mimic the natural soil salts. Kinetics and thermodynamic parameters of the adsorption were calculated at two different electrolyte concentrations: 0.05 N and 0.15 N. The adsorption was described by Langmuir and Freundlich isotherms. Results showed that lower concentration of the NaCl or Na2SO4 electrolytes (0.05 N) had higher adsorption capacity. Also, the maximum adsorption of cadmium when using sulfate counter ion is about two to three times higher than that when using chloride (544 µg/g for alluvial soil and 170 µg/g for calcareous soil when using 0.05 N). Using NaCl as matrix electrolyte, Freundlich isotherms showed bi-linear fits that probably mean a two energy level adsorption. This might be explained by either the competition of Cd(2+) with Na(+) or its complexation with Cl(-).


Subject(s)
Aluminum Silicates/chemistry , Cadmium/chemistry , Chlorides/chemistry , Ions , Silicon Dioxide/chemistry , Soil/chemistry , Sulfates/chemistry , Adsorption , Clay , Kinetics , Temperature
7.
Rev Neurol (Paris) ; 167(8-9): 615-8, 2011.
Article in French | MEDLINE | ID: mdl-21190704

ABSTRACT

INTRODUCTION: Air embolism is a rare complication of various invasive medical procedures. Venous cerebral air embolism is usually the consequence of paradoxical embolism. We report a case of isolated cerebral air embolism resulting from a non-paradoxical mechanism. CASE REPORT: A few minutes after his central venous catheter had been accidentally disconnected, a 63-year-old man developed left-sided rhythmic jerking movements followed by left hemiplegia. There were no associated cardiologic or pulmonary signs. Brain CT showed air bubbles in the right frontal cortical sulci. The brain MRI DWI and FLAIR sequences showed a high intensity right frontal cortical lesion without reduction in ADC. Transesophageal echocardiogram did not find a patent foramen ovale. CONCLUSIONS: In this case of venous cerebral air embolism, the lack of any cardiopulmonary manifestation, the lack of a patent foramen ovale and the neuroradiological findings are not in favor of the hypothesis of paradoxical embolism. The hypothesis of retrograde venous cerebral air embolism is discussed.


Subject(s)
Embolism, Air/etiology , Iatrogenic Disease , Brain/pathology , Catheterization, Central Venous/adverse effects , Cerebral Cortex/diagnostic imaging , Cerebral Cortex/pathology , Echocardiography, Transesophageal , Electroencephalography , Embolism, Air/pathology , Hemiplegia/etiology , Humans , Image Processing, Computer-Assisted , Lung Diseases/etiology , Magnetic Resonance Imaging , Male , Medical Errors , Middle Aged , Prefrontal Cortex/pathology , Radionuclide Imaging , Tomography, X-Ray Computed
8.
Respir Med ; 104(4): 510-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19944581

ABSTRACT

BACKGROUND: The role of combination ICS/LABA as initial controller therapy in mild, persistent asthma is uncertain. Therefore, the objective of this study was to compare the efficacy of initial controller therapy with fluticasone propionate (FP) 100 microg twice daily to the efficacy of fluticasone propionate/salmeterol xinafoate (FSC) 100/50 microg twice daily in patients with persistent asthma symptoms while using as-needed SABA alone. METHODS: This randomized, double-blind, parallel-group study was conducted at 45 general practice and 15 specialist centers. A total of 526 adult patients were randomized to receive FP or FSC for 24 weeks. The primary efficacy endpoint was change in morning peak expiratory flow (PEF) from baseline. Secondary efficacy endpoints included symptom- and rescue-free days; asthma exacerbation rate; asthma-related health-care utilization; and the onset of effect. Safety was assessed by monitoring adverse events. RESULTS: Mean morning PEF was significantly greater in the FSC versus the FP group (P<0.001); this greater effect was evident as early as the first week of treatment (P<0.001). The percentages of symptom-free days and rescue-free days in the FSC group were 7.7% (P=0.009) and 8.4% (P=0.001) higher than the FP group, respectively. Trends toward lower exacerbation-related health care-utilization for FSC versus FP were not statistically significant and exacerbation rates were not significantly different. The incidence of adverse events was low with both treatments. CONCLUSIONS: :Treatment with FSC was a more effective initial controller therapy than FP monotherapy in ICS-naïve patients who had uncontrolled asthma while using as-needed SABA alone.


Subject(s)
Adrenergic beta-Agonists/administration & dosage , Albuterol/analogs & derivatives , Androstadienes/administration & dosage , Asthma/drug therapy , Bronchodilator Agents/administration & dosage , Adolescent , Adult , Aged , Albuterol/administration & dosage , Asthma/epidemiology , Asthma/physiopathology , Canada/epidemiology , Child , Dose-Response Relationship, Drug , Double-Blind Method , Female , Fluticasone , Forced Expiratory Volume/drug effects , Humans , Male , Middle Aged , Salmeterol Xinafoate , Severity of Illness Index , Treatment Outcome , Young Adult
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