Cephalexin degradation initiated by OH radicals: theoretical prediction of the mechanisms and the toxicity of byproducts.

In this work, the density functional theory is used to study the local reactivity of cephalexin (CLX) to radical attack and explain the mechanism of the reaction between CLX and hydroxyl radical attack leading to degradation byproducts. The reaction between •OH and CLX is supposed to lead to either an addition of a hydroxyl radical or an abstraction of a hydrogen. The results showed that the affinity of cephalexin for addition reactions increases as it passes from the gas to the aqueous phase and decreases as it passes from the neutral to the ionized form. Thermodynamic data confirmed that OH addition radicals (Radd) are thermodynamically favored over H abstraction radicals (Rabs). The ecotoxicity assessments of CLX and its byproducts are estimated from the acute toxicities toward green algae, Daphnia, and fish. The formation of byproducts is safe for aquatic organisms, and only one byproduct is harmful to Daphnia.

[Vascular calcification in pseudoxanthoma elasticum in children]. / Calcifications vasculaires dans le pseudoxanthome élastique chez l'enfant.

INTRODUCTION: Vascular calcifications are associated with several diseases that affect vascular connective tissue and skin and cause considerable morbidity and mortality. The prototype of these conditions is pseudoxanthoma elasticum. We report, in this study, 4 pediatric cases of vascular calcifications diagnosed as elastic pseudoxanthoma. OBSERVATIONS: These 4 children were 2-11 years old and presented variable clinical features. Vascular involvement and arterial hypertension was observed in all patients, skin involvement in 2 cases, gastrointestinal involvement in 2 cases, neurological impairment in one case, and cardiac involvement in one case. Demonstration of ABCC6 gene mutations provided diagnostic confirmation in all cases. CONCLUSION: Pseudoxanthoma elasticum is a rare genetic disease, which can lead to many complications. Appropriate knowledge and early diagnosis are essential.

[Moyamoya disease associated with kidney angiodysplasia in a child]. / Maladie de Moya-Moya associée à une angiodysplasie rénale chez un enfant.

INTRODUCTION: Moyamoya disease is a progressive, chronic occlusive vascular disease of the circle of Willis arteries leading to the development of collateral circulation to compensate the occlusion. CASE REPORT: An 11-year-old girl presented an abrupt loss of consciousness and a right-sided motor deficit. Clinical examination found hypertension with 220/120mmHg arterial blood pressure. Brain magnetic resonance imaging showed a large left hemispheric ischemic lesion. Cerebral arteriography demonstrated an abnormal anastomotic vascular network with fine arteriolar ends in several territories, with a "wisp of smoke" aspect arguing in favor of moyamoya disease. Renal arteriography revealed dysplasia of the upper polar branches of the right kidney. CONCLUSION: Moyamoya disease is a rare cause of stroke in children. Its association with renal angiodysplasia is unusual and may be responsible for malignant hypertension. Cognitive impairment and social dependence have recently been recognized as an important unresolved social issue. Affected children require medical-surgical, social, and psychological care.

[Pseudoxanthoma elasticum: A rare cause of gastrointestinal bleeding in children]. / Pseudo-xanthome élastique : une cause rare d'hémorragies digestives chez l'enfant.

INTRODUCTION: Pseudoxanthoma elasticum (PXE) is a rare autosomal recessive connective tissue disorder, characterized by calcification and progressive fragmentation of elastic fibers. Gastrointestinal lesions are rare in children and may be responsible for serious complications. This article reports two pediatric cases of PXE revealed by gastrointestinal bleeding. CASE REPORTS: An 11-year-old boy and a 12-year-old girl were hospitalized for gastrointestinal bleeding. Digestive endoscopy showed hemorrhagic gastroenteritis bulbitis in the first case and it was normal in the second. Abdominal ultrasound showed diffuse linear calcifications in both cases. The diagnosis of PXE was retained based on the presence of vascular disease in both patients, a skin lesion in the girl, and an ocular lesion in the boy. The genetic study confirmed the diagnosis of PXE identifying two ABCC6 mutations in the composite state in the boy: the c.2263G> A (p.G755R) mutation on exon 18 and the c.3421C> T (pR1141X) mutation on exon 24 and the 4021G> A (R1164Q) mutation in the homozygous state of ABCC6 exon 24 in the girl. CONCLUSION: Digestive manifestations are unusual ; however, pseudoxanthoma elasticum should be considered in all cases of gastrointestinal bleeding for no apparent reason. Early diagnosis allows prevention and measures to control the risk factors and limit the progression of complications.

[Not isolated ventricular compaction in an infant]. / Non compaction ventriculaire isolée chez un nourrisson.

UNLABELLED: Not isolated ventricular compaction cardiomyopathy is a rare deasese described both in children than in adults. It due to the interruption of the embryogenic compaction process of the normal myocardium. We report a pediatric observation of noncompaction of the left ventricle. CASE REPORT: This is a 4-month girl who was admitted to an array of heart failure with systolic murmur to FM. Chest radiography showed cardiomegaly. The ECG showed repolarization disorder. The echocardiography objectified dilated left cavities with thickened wall and anechoic areas (sinusoidal), a mitral regurgitation GII and minimal tricuspid regurgitation. CONCLUSION: NCVI is a rare cause of heart failure in infants. The management is based on guidelines for various clinical symptomatology. Its discovery in children should lead to screening of first-degree relative.

[Psoriasis in infants about five cases]. / Le psoriasis chez le nourrisson à propos de cinq cas.

INTRODUCTION: Psoriasis is a skin disease very common. The diagnosis is clinical with a scaly erythema. Given the increasing frequency of cases of psoriasis of the child, we are interested in studying the role of this disease especially in infants. We report five cases of psoriasis collected in units of pediatric dermatology at Children's Hospital of Rabat. RESULTS: It is about a girl and four boys ranging in age between 41 days and 2 years. There is in three cases a family history of autoimmune disease, in two cases a notion of family atopée. Three cases among the five cases have plaque psoriasis, a case of psoriasis vulgaris, and one case of psoriatic diaper rash. All cases in our series were treated with emollients and topical corticosteroids. The outcome was favorable in five cases. CONCLUSION: Psoriasis is a multifactorial disease complex, multiple mechanisms, not well known, with combination of genetic, immunological and environmental factors. Treatment is in the light with corticosteroids, anti-inflammatory and immunomodulators obtained by genetic engineering techniques raises considerable hope in severe forms.

[Recurrent flaccid paralysis indicative of acute intermittent porphyria in a child]. / Paralysie flasque récidivante révélatrice d'une porphyrie aiguë intermittente chez un enfant.

UNLABELLED: Porphyrias are inherited metabolic diseases characterized by accumulation and increased excretion of porphyrins due to enzyme deficiencies involved in the biosynthesis of heme. Porphyrias are monogenic autosomal and mostly dominant disorders. CASE REPORT: A 10-year-old boy was diagnosed with acute intermittent porphyria on the basis of recurrent flaccid paralysis with red urine. Confirmation was obtained by measurement of urinary porphyrin precursors and chromatography of porphyrins. CONCLUSION: Acute intermittent porphyria is a severe form of hereditary porphyria with severe neurological complications during an acute episode. Specific investigations should be performed early and urgently in the presence of suggestive signs in a child.