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Aldol addition of α-triisopropylsilyl-α-diazoacetone (TIPS-diazoacetone), promoted by excess lithium diisopropylamide (LDA), was developed and applied to the synthesis of original C-TIPS diazoaldols, C-TIPS diazoketols, and a related Mannich-type product. An unprecedented mechanistic pathway has been proposed, involving a lithiated triazene intermediate resulting from the nucleophilic addition of LDA on the diazo moiety, supported by experimental results and DFT calculations.

α-Triisopropylsilyl-α-diazoacetone (TIPS-diazoacetone) underwent high-yielding “diazo-side” Mukaiyama aldol-type addition with a range of aryl and alkyl aldehydes when subjected to stoichiometric amount of tetrabutylammonium fluoride at −16 °C, in Et2O. Robustness of the TIPS group makes TIPS-diazoacetone a stable surrogate for α-triethylsilyl-α-diazoacetone, on which generation of the corresponding carbanion can still be efficiently achieved under nucleophilic, weakly basic and practical conditions. These results highlight the synthetic potential that can be expected from TIPS-diazoacetone, promising building block for the convergent elaboration of highly functionalised versatile diazocarbonyl compounds.

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Aldol-type addition of α-triethylsilyl-α-diazoacetone was achieved under nucleophilic activation by tetrabutylammonium fluoride (TBAF). The use of a semistoichiometric amount of TBAF (protocol P1) provided the corresponding β-hydroxy-α-diazoacetone as the sole product. Alternatively, the use of a catalytic amount of TBAF led to a mixture of β-hydroxy- and β-silyloxy-α-diazoacetone products, which was cleanly desilylated with Et3N·3HF (protocol P2). The weakly basic conditions employed tolerate a wide range of substrates and constitute a high-yielding, convenient complementary procedure to the low-temperature LDA-promoted aldol-type addition of diazoacetone.

While the involvement of the central nervous system in clinical phenotype of patients with Charcot Marie Tooth (CMT) disease has been reported in the past, the association with epilepsy has rarely been described. Only a few patients with CMT disease were reported in the literature to have epilepsy. We report the observation of a patient with CMT1A who also developed epileptic seizures. It is interesting to describe this case to show whether CMT and epilepsy are two different expressions of the same genetic abnormality or two different entities occurring together.

Rett syndrome is a monogenic X-linked dominant neurodevelopmental disorder related to mutation in MECP2, which encodes the methyl-CpG–binding protein MeCP2. The aim of this study was to search for mutations of MECP2 gene in Tunisian Rett patients and to evaluate the impact of the found variants on structural and functional features of MeCP2. The result of mutation analysis revealed that 3 Rett patients shared the same novel heterozygous point mutation c.175G>C (p.A59P). The p.A59P mutation was located in a conserved amino acid in the N-terminal segment of MeCP2. This novel mutation confers a phenotypic variability with different clinical severity scores (3, 8, and 9) and predicted by Sift and PolyPhen to be damaging. Modeling results showed that p.A59P adds 2 hydrogen bonds and changes the structural conformation of MeCP2 with a significant root mean square deviation value (9.66 Å), suggesting that this mutation could probably affect the conformation, function and stability of MeCP2.

Primary peritonitis is defined as peritoneal infection without an evident intra peritoneal septic focus. In the absence of these conditions, primary peritonitis is exceptional, and only few cases were reported in the literature. Here we report two cases of primary peritonitis in immunocompetent children. Although rarely encountered, primary peritonitis should be included in the differential diagnosis of acute abdominal pain in children.

Ovarian masses requiring surgical intervention are uncommon in the pediatric population. Our aim is to report results of a multicentric Tunisian study concerning the clinical practice and the management of pediatric ovarian masses and to identify the factors that are associated with ovarian preservation. Between January 2000 and December 2015, 98 pediatric patients (14 years) were surgically treated for ovarian masses at the five pediatric surgery departments in Tunisia. Ninety-eight patients were included in this study. The mean age of the patients at time of surgery was 8.46 ± 4.87 years. Sixty-three ovarian masses (64.3%) were non-neoplastic lesions, 24 (24.5%) were benign tumors, and 11 (11.2%) were malignant neoplasms. Conservative surgery (ovarian-preserving surgery) was successfully performed in 72.4% of the benign lesions, whereas only three patients (27.3%) with malignant tumors underwent ovary-sparing tumor resection (p .001). The mean diameter of the tumors in the patients who underwent oophorectomy was significantly larger than that in the patients who underwent conservative surgery (7.8 ± 3.9 cm vs. 5.7 ± 2.9 cm, respectively, p = .001). In our study, the risk factors for oophorectomy were a malignant pathology and large tumor size. In accordance with the Gynecologic Cancer Intergroup consensus, we recommend that surgical management of ovarian masses in children should be based on ovarian-preserving surgery.

Perinatal testicular torsion (PTT) is a rare entity. The management of PTT is controversial, due to the low viability of the testis and the possibility of bilateral torsion. This is a review of our experience with six cases of PTT, highlighting diagnostic and therapeutic difficulties of this condition.

Summary Charcot-Marie-Tooth (CMT) disease constitutes a clinically and genetically heterogeneous group of hereditary neuropathies characterized by progressive muscular and sensory loss in the distal extremities with chronic distal weakness, deformation of the feet, and loss of deep tendon reflexes. CMT4H is an autosomal recessive demyelinating subtype of CMT, due to mutations in FGD4/FRABIN, for which nine mutations are described to date. In this study, we describe three patients from a consanguineous Tunisian family, presenting with severe, early onset, slowly progressive, autosomal recessive demyelinating CMT, complicated by mild to severe kyphoscoliosis, consistent with CMT4H. In these patients, we report the identification of a novel homozygous frameshift mutation in FGD4: c.514_515insG; p.Ala172Glyfs ∗ 27. Our study reports the first mutation identified in FGD4 in Tunisian patients affected with CMT. It further confirms the important clinical heterogeneity observed in patients with mutations in FGD4 and the lack of phenotype/genotype correlations in CMT4H. Our results suggest that FGD4 should be screened in other early-onset CMT subtypes, regardless of the severity of the phenotype, and particularly in patients of consanguineous descent. In Tunisians, as in other populations with high consanguinity rates, screening of genes responsible for rare autosomal recessive CMT subtypes should be prioritized.

Enterobius vermicularis (EV) is the most common helminthic infection in the world. This small parasite is predominant in the pediatric population. The presence of EV in the appendix can cause or mimick appendicitis. The aim of our study was to compare patients with EV infection and those without EV infection, and to identify predictive factors that may help the diagnosis of EV infection in patients presenting with right iliac fossa pain and avoid negative appendectomy.A retrospective analysis of all the appendices removed between January 2012 and December 2016 was conducted at the department of pediatric surgery, Hedi Chaker Hospital, Sfax, Tunisia. According to the final histopathological diagnosis, patients with EV infection were compared to those without EV infection. Data including age, sex, white blood cell (WBC) count, neutrophil count, eosinophil count, C-reactive protein, and ultrasound results for both groups were analyzed and compared. The study protocol was approved by the local hospital ethics committee. Statistical analysis was performed using IBM SPSS, version 20. Descriptive analysis in the form of mean and standard deviation was performed on demographic information. Differences between groups were assessed using the student t-test for continuous variables and the χ2 test and Fisher exact test where appropriate for categorical variables.In total, 540 pediatric appendectomies were performed. Overall, 63.5% of patients were male and 36.5% were female. Mean age was 9.28 ± 2.77 years. 22.2% of procedures were completed laparoscopically, 76.5% were open and 1.3% were converted. The negative appendectomy rate was 11.1%. EV was present in 9.8% of cases. Comparison of clinical, biological, and ultrasound findings between two groups of patients with EV (EV+) and those without EV (EV-) shows a statistical significance for pruritus ani (P0.001), WBC count (P0.001), neutrophil count (P0.001), C-reactive protein (CRP) (P = 0.001), positive ultrasound (P0.001), perforation rate (P = 0.009), and negative appendectomy rate (P0.001). No significant difference between the two groups was seen when comparing gender (P = 0.271), vomiting (P = 0.130), eosinophil count (P = 0.915), and procedure (P = 0.536).EV was seen in 9.8% of pediatric appendectomies in our study. Pruritus ani, normal WBC count, normal neutrophil count, and normal CRP level at presentation could predict EV infection in children who present with right iliac fossa pain.

Introduction Le syndrome de Parry-Romberg (SPR) est caracterise par une atrophie hemifaciale acquise progressive touchant la peau, le tissu sous-cutane, les muscles et les structures osteocartilagineuses. Les manifestations neuro-ophtalmologiques sont rares. Objectifs Analyser les caracteristiques cliniques, radiologiques et biologiques d’une serie de 3 enfants suivis pour SPR. Methodes C’est une etude retrospective transversale des dossiers de 3 patients suivis au service de neurologie pediatrique au CHU Hedi Chaker de Sfax-Tunisie pour un SPR. Chaque patient a beneficie d’un examen neurologique, ophtalmologique et somatique complet ainsi qu’une imagerie cerebrale et osseuse. Resultats L’âge moyen de debut etait 8 ans par une hypotrophie hemifaciale, une deficience intellectuelle, ataxie, syndrome quuadripyramidal et une epilepsie focale. Une enophtalmie etait presente chez 2 patients et une retinite pigmentaire chez un. L’IRM cerebrale avait objective une atteinte inflammatoire la substance blanche (SB) chez un et une atteinte retractile de la SB hemispherique et du noyau thalamique homolateral chez un. L’asymetrie osseuse etait objectivee au scanner facial et le bilan immunologique etait negatif chez tous. Discussion Les manifestations neurologiques representent les manifestations systemiques les plus frequentes au cours du SPR (15 %) suivies par l’atteinte ophtalmologique. Chez nos patients l’atteinte neuro-ophtalmologique est presente dans 100 % des cas. Ces manifestations peuvent etre concomitantes aux manifestations cutanees ou tardives. Il a ete propose de considerer SPR comme un syndrome neurocutane. Conclusion SPR est une affection rare de physiopathologie inconnue. Il est associe a diverses atteintes systemiques avec un retentissement fonctionnel neurologique. Le traitement est non consensuel reposant sur corticoide et immunosuppresseur.

Aldol-type addition of α-triethylsilyl-α-diazoacetone was achieved under nucleophilic activation by tetrabutylammonium fluoride (TBAF). The use of a semistoichiometric amount of TBAF (protocol P1) provided the corresponding β-hydroxy-α-diazoacetone as the sole product. Alternatively, the use of a catalytic amount of TBAF led to a mixture of β-hydroxy- and β-silyloxy-α-diazoacetone products, which was cleanly desilylated with Et3N·3HF (protocol P2). The weakly basic conditions employed tolerate a wide range of substrates and constitute a high-yielding, convenient complementary procedure to the low-temperature LDA-promoted aldol-type addition of diazoacetone.

In this paper, multichannel image processing using an adaptive approach is the subject of our study. Thus, we have proposed a new Adaptive Vector Directional Distance Filter (VDDF). Simulation results illustrate that this new proposed filter outperforms the classic Vector Directional Distance Filterwhen images are contaminated with impulsive noise. In addition, efficiency of this filter is proven since it provides an excellent balance between the noise attenuation and the signal-details preservation.

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Learning disorders are increasingly a concern for Tunisians parents. These difficulties are divided into two groups: specific learning disabilities and non-specific learning disorders.Our work is part of a federated research project. Our aim is to determine the incidence, etiology and management of learning disorders in the region of Sfax.We conducted a descriptive cross-sectional study on a population of 304 children assessed by their teachers as having academic difficulty. A multidisciplinary assessment including a neurological examination, an assessment of score of intelligence and language assessment has been performed for 209 children.Referring to our sample, learning disorders affect 21.3% of children in the region Sfax. The frequency of specific learning disorder is estimated at 10.3% (reading disorder 5.9%, dyscalculia 2.4%, reading disorder associated with dyscalculia 2%). Non-specific learning disorders were found in 11% of children. Etiologies in this group were dominated by mental retardation (2.1%), inappropriate education (2.3%).Our study revealed the high frequency of learning difficulties. It allows us to distinguish between specific learning disabilities and non specific learning disorders secondary to neurological or precarious socio-economic conditions. However, the profile and severity of specific learning disorders could not be studied due to the lack of standardized Arabic tests in Tunisia. In countries with a lack of professional and specialized unit care as in Tunisia, reading interventions in school should be proposed. Only children with remaining difficulties after this training will be sent to specialized professionals.

Charcot-Marie-Tooth (CMT) disease constitutes a clinically and genetically heterogeneous group of hereditary neuropathies characterized by progressive muscular and sensory loss in the distal extremities with chronic distal weakness, deformation of the feet, and loss of deep tendon reflexes. CMT4H is an autosomal recessive demyelinating subtype of CMT, due to mutations in FGD4/FRABIN, for which nine mutations are described to date. In this study, we describe three patients from a consanguineous Tunisian family, presenting with severe, early onset, slowly progressive, autosomal recessive demyelinating CMT, complicated by mild to severe kyphoscoliosis, consistent with CMT4H. In these patients, we report the identification of a novel homozygous frameshift mutation in FGD4: c.514_515insG; p.Ala172Glyfs*27. Our study reports the first mutation identified in FGD4 in Tunisian patients affected with CMT. It further confirms the important clinical heterogeneity observed in patients with mutations in FGD4 and the lack of phenotype/genotype correlations in CMT4H. Our results suggest that FGD4 should be screened in other early-onset CMT subtypes, regardless of the severity of the phenotype, and particularly in patients of consanguineous descent. In Tunisians, as in other populations with high consanguinity rates, screening of genes responsible for rare autosomal recessive CMT subtypes should be prioritized.