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N Sans

Publications and source records attributed to N Sans.

At least 19 recordsLinked to original sources
PubMed2000

A developmental change in NMDA receptor-associated proteins at hippocampal synapses.

The membrane-associated guanylate kinases [Chapsyn-110/postsynaptic density-93 (PSD-93), synapse-associated protein-90 (SAP-90)/PSD-95, and SAP-102] are believed to cluster and anchor NMDA receptors at the synapse and to play a role in signal transduction. We have investigated the developmental changes in expression of these proteins in rat hippocampus using biochemical analyses and quantitative immunogold electron microscopy. At postnatal day 2 (P2), SAP-102 was highly expressed, whereas PSD-93 and PSD-95 were low. SAP-102 expression increased during the first week, stayed stable through P35, and showed a reduced expression at 6 months. From P2 through 6 months, PSD-93 and PSD-95 increased. For PSD-95, the percent of labeled synapses increased almost threefold with age, whereas the number of gold particles per labeled synapse did not change significantly, suggesting that the increase in PSD-95 is attributable primarily to an increase in the number of synapses containing PSD-95. In contrast, for SAP-102, both percent labeled synapses and the number of gold particles per labeled synapse decreased during this time. From Western blots of hippocampus and immunogold analysis of CA1 synapses, the high expression of NR2B at P2 coincides with the high level of SAP-102 at synapses, whereas the later expression of NR2A coincides with that of PSD-93 and PSD-95. To determine whether the changes in PSD-93/95 and SAP-102 reflect preferred associations with NR2A and NR2B, respectively, we measured co-immunoprecipitation in the adult hippocampus. These studies suggest that there is a preference for complexes of NR2A/PSD-93/95 and NR2B/SAP-102. These results indicate that individual receptor-associated proteins may have specific functions that are critical to synapse development.

Aging↗
PubMed2000

PDZ domain suppression of an ER retention signal in NMDA receptor NR1 splice variants.

The NMDA receptor NR1 subunit has four splice variants that differ in their C-terminal, cytoplasmic domain. We investigated the contribution of the C-terminal cassettes, C0, C1, C2, and C2', to trafficking of NR1 in heterologous cells and neurons. We identified an ER retention signal (RRR) in the C1 cassette of NR1, which is similar to the RXR motif in ATP-sensitive K(+) channels (Zerangue et al., 1999). We found that surface expression of NR1-3, which contains C1, is due to a site on the C2' cassette, which includes the terminal 4 amino acid PDZ-interacting domain. This site suppresses ER retention of the C1 cassette and leads to surface expression. These findings suggest a role for PDZ proteins in facilitating the transition of receptors from an intracellular pool to the surface of the neuron.

Alternative Splicing↗
PubMed2000

[Carney's triad: update and report of one case].

The Carney's syndrome associates three different tumors on the same subject, a young woman generally: a gastric leiomyosarcoma, a pulmonary chondroma and a non adrenal paraganglioma. The authors report a new case of that unfrequent syndrome of unexplained pathogeny.

Adrenal Gland Neoplasms↗
PubMed2000

[Capsular retraction of shoulder: prospective study of imaging benefits in 20 patients].

PURPOSE: To evaluate the contribution of principal imaging techniques in diagnosis and treatment in adhesive capsulitis of the shoulder. MATERIALS AND METHODS: In 20 patients presenting adhesive capsulitis of shoulder since mean of 6,7 months, the following examinations were performed: radiographies, angioscintigraphy, MRI as well as an opaque arthrography and a bursography associated with corticosteroid injection. Patients were followed during one year. RESULTS: The opaque arthrography was to affirm the adhesive capsulitis for the inclusion of the patients. Radiographies (patchy demineralization) and scintigraphy (hyperfixation) were often pathological. In MRI, T1 fat-saturated sequences after contrast injection almost always showed enhancement of the articular capsula, the synovia, the miscellaneous bone or the sub-acromial bursa. The latter was often modified and retracted at bursography. In 19 of 20 cases, a functional improvement was observed after the opacifications. CONCLUSION: Therapeutic effect of both arthrography and bursography is almost proved. Post contrast MRI confirms presence of vascular troubles in all the shoulder structures even at this advanced stage.

Adult↗
PubMed2000

[Thoracic ultrasound].

Ultrasound exploration of the thorax is a very useful imaging method in children. For adults, it is useful for pleural effusion, study of the diaphragm and to guide percutaneous puncture of targeted pleuro-parietal, mediastinal or peripheral parenchymal sites. Thoracic ultrasound remains underused, particularly as a bedside exploration technique or in emergency or intensive care situations.

Adult↗
PubMed2000

[HASTE sequence and cine-MRI evaluation of the cervical spinal canal: evaluation in 11 healthy subjects].

PURPOSE: We studied 11 healthy subjects were evaluated using cine MR imaging comparing HASTE and gradient echo sequences. Materials and methods :HASTE is a high-speed turbo-spin echo T2-weighted sequence. All examinations were performed using dynamic MRI using a simple process allowing acquisition of images at different stages during flexion and extension. The cine MR evaluation was obtained by rebuilding a cine-loop sequence. RESULTS: HASTE sequence provides a myelographic effect of the cervical spine. The size, the pattern and the movements of the cervical spine, the spinal cord, as well as the functional reserve of cerebro-spinal fluid are analysable. CONCLUSION: Because of its very high speed, HASTE sequence is particularly useful for cine MR imaging.

Adult↗
PubMed2000

[The lumbar epidural space. Radio-anatomical study].

The epidural space which extends along the spine, surrounds the dural sac and is bounded by the bony and ligamentous structures of the vertebral canal. The knowledge of the anatomy of this region is important because the high frequency of the pathological processes in this area (tumoral, infections, vascular). The purpose of this presentation is to present the normal radio-anatomy of the lumbar epidural space and then the main pathological processes of this region.

Epidural Space↗
PubMed1999

Is capsular retraction a specific CT sign of malignant liver tumor?

The aim of this study was to assess if a liver capsular retraction is a specific CT sign in malignant hepatic tumors. The authors reviewed retrospectively 320 hepatic CT scans obtained in 300 patients during a 3-year period. These patients presented with benign (n = 64) or malignant (n = 236) hepatic tumors. In 7 patients we found retraction of the capsule surrounding the tumor. All these tumors were histologically proven as malignant lesions: 4 metastases (none being chemically treated), 2 peripheral cholangiocarcinomas, and 1 epithelioid hemangioendothelioma. The prevalence of this sign was 2.18% (7 of 320) in this series. This capsular retraction pattern has never been found in hepato-cellular carcinomas (no fibrolamellar in this series) and benign lesions. Liver capsular retraction is an uncommon but specific (100%) sign in malignant hepatic tumors; however, a larger and prospective series is needed.

Humans↗
PubMed1999

[Percutaneous drainage of infected pancreatic necrosis: an alternative to surgery].

AIM OF THE STUDY: To describe a technique of percutaneous CT guided catheter drainage of infected pancreatic necrosis and to report the results of this technique compared with those of the conventional surgical treatment and of other percutaneous drainage series. PATIENTS AND METHODS: Between 1992 and 1997, the series included 32 patients who had a severe acute necrotizing pancreatitis with a mean Ranson score of 4.6, scored into grade D (n = 10), and grade E (n = 22), according to the Balthazar radiological staging. Modified Van Sonnenberg 24 F double lumen catheters were used for continuous irrigation and aspiration. RESULTS: Forty-nine drains were inserted for 41 infected necroses and eight abscesses. Among the 32 patients, the proof of infected necrosis was obtained in 26 patients by fine needle aspiration and culture (enterococcus, staphylococcus, pseudomonas). The average delay of catheter insertion was 23 days after onset of pancreatitis; the mean duration of drainage was 43 days, and an average of three catheters per patient was required. Five patients (15%) died, and among the survivors, 16 (59%) presented 21 complications including 14 enterocutaneous or pancreatic fistulas. A subsequent surgical procedure including two necrosectomies was necessary in six patients. CONCLUSION: This study demonstrates that percutaneous drainage of infected pancreatic necrosis with a 15% mortality and 70% success rate, represents an interesting alternative to conventional surgery.

Abscess↗
PubMed1999

Cloning and expression of succinic semialdehyde reductase from human brain. Identity with aflatoxin B1 aldehyde reductase.

The neuromodulator gamma-hydroxybutyrate is synthesized in vivo from gamma-aminobutyrate by transamination to succinic semialdehyde and subsequent reduction of the aldehyde group. In human brain, succinic semialdehyde reductase is thought to be responsible for the conversion of succinic semialdehyde to gamma-hydroxybutyrate. In the present work, we cloned the cDNA coding for succinic semialdehyde reductase and expressed it in Escherichia coli. A data bank search indicated that the enzyme is identical with aflatoxin B1-aldehyde reductase, an enzyme implicated in the detoxification of xenobiotic carbonyl compounds. Structurally, succinic semialdehyde reductase thus belongs to the aldo-keto reductase superfamily. The recombinant protein was indistinguishable from native human brain succinic semialdehyde reductase by SDS/PAGE. In addition to succinic semialdehyde, it readily catalyzed the reduction 9,10-phenanthrene quinone, phenylglyoxal and 4-nitrobenzaldehyde, typical substrates of aflatoxin B1 aldehyde reductase. The results suggest multiple functions of succinic semialdehyde reductase/aflatoxin B1 aldehyde reductase in the biosynthesis of gamma-hydroxybutyrate and the detoxification of xenobiotic carbonyl compounds, respectively.

Aldehyde Reductase↗
PubMed1999

Osteoid osteoma: CT-guided percutaneous resection and follow-up in 38 patients.

PURPOSE: To reevaluate at medium term the results of computed tomography (CT)-guided percutaneous resection of osteoid osteomas. MATERIALS AND METHODS: Thirty-eight patients who had undergone treatment by means of this technique were reexamined with a mean follow-up of 3.7 years. The short- and medium-term clinical course and histologic features of the resection specimens were analyzed. RESULTS: The bone fragment could be analyzed in all cases, and the diagnosis of osteoid osteoma was confirmed in 28 patients (74%). A different diagnosis was made in six patients: mucoid cyst, subchondral arthritic geode, fibrous dysplastic lesion, focal osteochondritis, or focal chronic osteomyelitis. Cure was obtained in 32 patients (84%), whatever the cause. Complications, generally minor and transient, were observed in nine patients (24%). The most severe complications were two femoral fractures and one focal chronic osteomyelitis due to Staphylococcus aureus infection. CONCLUSION: The results of this study confirm the efficacy of percutaneous resection of osteoid osteomas and the possibility of using this method for successful treatment of other small bone lesions.

Adolescent↗
PubMed1999

[Lateral view of the thorax: the profile].

The lateral view of the chest is a complementary incidence performed less frequently nowadays with the great frequency of chest CT. In fact, this lateral radiograph has important potential and can even give some exclusive information. With the 3-dimensional visualization provided by CT, the lateral radiograph of the chest is even easier to understand. Following in the footsteps of our great predecessors (Felson, Heitzman, Proto) we propose the left lateral view and offer our opinion about indications, techniques and results. The left lateral view can be performed with perfect perpendicular orientation or with a slight lateral shift that can be chosen with the right shoulder forwards (shifted right anterior lateral) or the contrary (shifted left anterior lateral). The left lateral view, like the antero-posterior view must be interpreted in a circular-concentric fashion.

Heart Diseases↗
PubMed1999

[Snapping scapula: the value of 3D imaging].

Snapping scapula is a rare and poorly known cause of shoulder pain and is related to mechanical impingement between the scapula and the rib cage. We present a case in which CT scan was valuable, as a complement to clinical evaluation, for demonstrating the bony component of this entity. 3D reconstructions greatly facilitated diagnosis.

Adult↗
PubMed1999

[Percutaneous resection under computed tomography guidance of osteoid osteoma. Mid-term follow-up of 38 cases].

PURPOSE: To evaluate the mid-term outcome following CT-guided percutaneous resection of osteoid osteoma. MATERIALS AND METHODS: 38 patients who had been treated by CT-guided percutaneous resection were included. The mean follow-up of 3.7 years. Early and mid-term outcome and histology were analyzed. RESULTS: Histological samples were adequate in 92% of cases and a diagnosis of osteoid osteoma was confirmed in 73.7% of cases. In 6 cases, the lesion was not an osteoid osteoma: 2 mucoid cysts, 1 benign fibrous dysplasia, 1 fibromucoid lesion, 1 focal osteochondritis, 1 osteomyelitis. Cure was achieved in 84.2% of patients. Minor transient complications occurred in 23.7% of cases. The most serious complications included: 1 intramuscular hematoma, 2 femoral fractures, and 1 case of S. aureus osteomyelitis. CONCLUSION: This study confirms that CT-guided percutaneous resection of osteoid osteomas is effective and shows that other small lesions can also be treated using this technique.

Adolescent↗