Transcranial sonographic measurement of the third ventricle to detect hydrocephalus in children population: Correlation to computed tomography.

BACKGROUND: In neuro-intensive care, transcranial temporal ultrasound is used in adults and children to monitor brain-injured patients. It is accepted as a valuable tool for exploring brain structures. Our study aims to establish a correlation between the measurement of the third ventricle (V3) by transcranial ultrasound via temporal window and a reference method, computed tomography (CT), which could validate the method for hydrocephalus detection in the children population. DESIGN: This is a prospective double-blind study of 34 children under 15 years. Two consultants in intensive care performed the ultrasound while a radiologist performed the CT measurements. RESULTS: Of the 34 patients included, the V3 could be measured in 88% of cases. Among these 30 patients, there is a good correlation between CT and ultrasound measurements with a Spearman correlation coefficient of 0.773. This correlation is more important as the diameter of the V3 increases. We could determine a threshold of 3.65 mm in diameter to identify hydrocephalus on ultrasound with a detection sensitivity of 100%, and a specificity of 94.1%. CONCLUSION: Measuring the diameter of the V3 by trans-cranial sonography remains a simple, reproducible, non-invasive tool and has a good correlation with reference examinations such as CT.

Cherubism: a rare case report with literature review.

Cherubism is an autosomal dominant disorder caused by a mutation of the gene encoding the binding protein SH3BP2. However, non-hereditary forms are observed, probably related to a de novo mutation. It is clinically manifested by an enlargement or a deformation of the jaw associated with a malposition of the teeth. In severe forms, these deformations can have a psychological impact, associated with ocular complications, as well as a reduction of the pharynx lumen and phonation disorders. The appearance of the lesions on imaging is not very specific, however it remains essential for the mapping of the lesions. We report a case of cherubism in a 12-year-old boy with no family history. This case report's objective is to identify the radiological aspect of this pathology and establish an early diagnosis to oriented therapeutic interventions.

Eye of the Tiger Sign in Pantothenate Kinase-Associated Neurodegeneration.

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare disorder associated with brain iron accumulation caused by a recessive mutation in pantothenate kinase 2 gene (PANK2). We present a case of an 11 year-old boy presenting extrapyramidal signs and developmental regression. T2-weighted images showed the classic eye of the tiger sign seen in pantothenate kinase-associated neurodegeneration.

Low solvothermal synthesis and characterization of hollow nanospheres molybdenum sulfide.

Hollow nanospheres of molybdenum disulfide have been synthesized by a novel solvothermal method under low temperature (180 degrees C). These nanomaterials were characterized by X-ray diffraction (XRD), Fourier transformation infra-red spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM, HRTEM) and X-ray Photoelectron Spectroscopy (XPS). A mechanism for the synthesis reaction is tentatively proposed and discussed.

[Typical form of Mayer-Rokitansky-Küster-Hauser syndrome and ectopic kidney. A rare association]. / Forme typique du syndrome de Mayer-Rokitansky-Küster-Hauser et rein ectopique : association rare.

The Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a spectrum of Müllerian anomalies characterized by congenital vaginal aplasia and absent uterus or a rudimentary one in female subjects with normal endocrine status. The ovaries and fallopian tubes are present. The prime feature is a primary amenorrhea in women presenting normally developed secondary sexual characteristics and normal external genitalia. The etiology remains unknown. This syndrome is subdivided in two types. It may be isolated (type I) or associated with other malformations (type II). Type I is less frequent than type II. We report a case of MRKH syndrome in a 21-year-old woman who presented a primary amenorrhea studied with transabdominal and pelvic ultrasonography and pelvic magnetic resonance, which demonstrated a complete agenesis of uterus, a functional cyst in the right ovary, and a left pelvic ectopic kidney. We studied the MRKH syndrome with review of the literature.

[Tuberculosis of the sternum]. / Localisation sternale de la tuberculose osseuse.

Isolated involvement of the sternum is rare, representing less than 1% of tuberculosis osteomyelitis. Only a few cases of sternal tuberculosis have been reported in the pediatric literature. The authors report the case of a 10 year old boy presenting with a 6 month history of presternal swelling and pain. Computed tomography (CT) showed a ring-enhancing hypodense soft tissue mass surrounding the sternum, with marked cortical thickening. Treatment included both surgical intervention and medical therapy.

[Sub occipital Pott's disease: report of 8 cases]. / Tuberculose de la jonction caranio-rachidienne. A propos de 8 observations.

Craniocervical Pott's disease remains exceptional, and may cause spinal instability and severe cervicomedullary complications. We report eight cases of tuberculous spondylodiscitis at the craniocervical junction revealed by signs of spinal cord compression, torticollis and dysphagia. The value of CT and MR imaging is discussed.

The ratio between CcdA and CcdB modulates the transcriptional repression of the ccd poison-antidote system.

The ccd operon of the F plasmid encodes CcdB, a toxin targeting the essential gyrase of Escherichia coli, and CcdA, the unstable antidote that interacts with CcdB to neutralize its toxicity. Although work from our group and others has established that CcdA and CcdB are required for transcriptional repression of the operon, the underlying mechanism remains unclear. The results presented here indicate that, although CcdA is the DNA-binding element of the CcdA-CcdB complex, the stoichiometry of the two proteins determines whether or not the complex binds to the ccd operator-promoter region. Using electrophoretic mobility shift assays, we show that a (CcdA)2-(CcdB)2 complex binds DNA. The addition of extra CcdB to that protein-DNA complex completely abolishes DNA retardation. Based on these results, we propose a model in which the ratio between CcdA and CcdB regulates the repression state of the ccd operon. When the level of CcdA is superior or equal to that of CcdB, repression results. In contrast, derepression occurs when CcdB is in excess of CcdA. By ensuring an antidote-toxin ratio greater than one, this mechanism could prevent the harmful effect of CcdB in plasmid-containing bacteria.

[An unusual cerebral hydatid cyst]. / Un kyste hydatique cérébral particulier.

Hydatid cysts of the brain are very rare. Typically, the cyst is large, spherical, with sharply defined borders. Its may calcify, and there is no surrounding edema and no rim enhancement. Sometimes, one side of the cyst wall is very close to the calvarium, with thinning of the internal table. We report a case of hydatid cyst of the brain with particular scanographic signs, bilobular with thin membranes in the posterior component. There was a destruction of the opposite calvarium with exteriorisation into hypodermic soft tissue.

[A rare primitive neuroectodermal tumor: the medulloepithelioma]. / Une tumeur neuroectodermique primitive rare: le medulloepitheliome.

Primitive neuroectodermal tumors (PNET) is a name used to describe rare and highly malignant tumors composed of undifferentiated cells resembling germinal or matrix cells of the embryonic neural tube. These tumors occur most commonly in the first decade of life, and have a particular radiological, histological and evolution features. We report a case of a PNET in an 8-year-old boy who presented intracranial hypertension studied with computed tomography scan, which demonstrated a sharply circumscribed expansive mass in the frontoparietal deep white matter, with a large cystic component, which was considered at first as a glial tumor. It was treated by total excision, and the histologic study demonstrated a medulloepithelioma. We studied the concept of PNET and their pathological, radiological and prognostic features.

Interactions of CcdB with DNA gyrase. Inactivation of Gyra, poisoning of the gyrase-DNA complex, and the antidote action of CcdA.

The F plasmid-carried bacterial toxin, the CcdB protein, is known to act on DNA gyrase in two different ways. CcdB poisons the gyrase-DNA complex, blocking the passage of polymerases and leading to double-strand breakage of the DNA. Alternatively, in cells that overexpress CcdB, the A subunit of DNA gyrase (GyrA) has been found as an inactive complex with CcdB. We have reconstituted the inactive GyrA-CcdB complex by denaturation and renaturation of the purified GyrA dimer in the presence of CcdB. This inactivating interaction involves the N-terminal domain of GyrA, because similar inactive complexes were formed by denaturing and renaturing N-terminal fragments of the GyrA protein in the presence of CcdB. Single amino acid mutations, both in GyrA and in CcdB, that prevent CcdB-induced DNA cleavage also prevent formation of the inactive complexes, indicating that some essential interaction sites of GyrA and of CcdB are common to both the poisoning and the inactivation processes. Whereas the lethal effect of CcdB is most probably due to poisoning of the gyrase-DNA complex, the inactivation pathway may prevent cell death through formation of a toxin-antitoxin-like complex between CcdB and newly translated GyrA subunits. Both poisoning and inactivation can be prevented and reversed in the presence of the F plasmid-encoded antidote, the CcdA protein. The products of treating the inactive GyrA-CcdB complex with CcdA are free GyrA and a CcdB-CcdA complex of approximately 44 kDa, which may correspond to a (CcdB)2(CcdA)2 heterotetramer.

Association of mutations in grlA and gyrA topoisomerase genes with resistance to ciprofloxacin in epidemic and sporadic isolates of methicillin-resistant Staphylococcus aureus.

The types of topoisomerase alterations in genomically diverse epidemic and sporadic strains of methicillin- and fluoroquinolone-resistant Staphylococcus aureus isolated from European hospitals between 1984 and 1994 were characterized. Convergent dual mutations in gyrA (codon 83, 84, or 88) and grlA (codon 79 and/or 80) were found in all strains exhibiting high-level resistance to ciprofloxacin (MIC, 16 to > or = 128 microg/ml). In some epidemic strains, the resistant phenotype and genotype appeared in the 1990s and persisted thereafter.