Superfluid high REynolds von Kármán experiment.

The Superfluid High REynolds von Kármán experiment facility exploits the capacities of a high cooling power refrigerator (400 W at 1.8 K) for a large dimension von Kármán flow (inner diameter 0.78 m), which can work with gaseous or subcooled liquid (He-I or He-II) from room temperature down to 1.6 K. The flow is produced between two counter-rotating or co-rotating disks. The large size of the experiment allows exploration of ultra high Reynolds numbers based on Taylor microscale and rms velocity [S. B. Pope, Turbulent Flows (Cambridge University Press, 2000)] (Rλ > 10000) or resolution of the dissipative scale for lower Re. This article presents the design and first performance of this apparatus. Measurements carried out in the first runs of the facility address the global flow behavior: calorimetric measurement of the dissipation, torque and velocity measurements on the two turbines. Moreover first local measurements (micro-Pitot, hot wire,…) have been installed and are presented.

Liquid helium inertial jet for comparative study of classical and quantum turbulence.

We present a new cryogenic wind tunnel facility developed to study the high Reynolds number developed classical or quantum turbulence in liquid (4)He. A stable inertial round jet flow with a Reynolds number of 4 × 10(6) can be sustained in both He I and He II down to a minimum temperature of 1.7 K. The circuit can be pressurized up to 3.5 × 10(5) Pa. The system has been designed to exploit the self-similar properties of the jet far field in order to adapt to the spatial resolution of the existing probes. Multiple and complementary sensors can be simultaneously installed to obtain spatial and time resolved measurements. The technical difficulties and design details are described and the system performance is presented.

Surgical treatment of large vestibular schwannomas (stages III and IV).

OBJECTIVE: Study the results of surgical treatment of large vestibular schwannomas. MATERIAL AND METHODS: Between January 1995 and December 2005, 87 stage III and IV unilateral vestibular schwannomas (Koos classification) were operated. RESULTS: The approach used was for the most part translabyrinthine. Nine patients were operated in two phases. Tumor exeresis was total in 79% of the cases, nearly total in 17%, and subtotal in 3.6%. Good facial function was preserved in 63% of the patients. Mortality was zero. Tumor control after a mean follow-up of 45 months was 86%. CONCLUSIONS: Surgery for large vestibular schwannomas should have a 0% mortality rate and low morbidity. Otoneurosurgical collaboration, with a preference for the translabyrinthine approach, with surgery undertaken in several phases if need be, provides maximum safety and good functional results as well as an acceptable residual tumor rate.

[Recurrent giant cystic vestibular schwannomas: role of cystoperitoneal shunt]. / Schwannomes vestibulaires kystiques géants: intérêt du drainage kystopéritonéal.

INTRODUCTION: Surgical removal of giant cystic vestibular schwannomas is difficult because of adherences between the cyst membrane, brainstem, and the VII-VIII nerve complex. The recurrence of the cyst is frequent and requires reoperation. The aim of this study was to analyze the role of the palliative cystoperitoneal shunt in giant cystic vestibular schwannomas. MATERIALS AND METHODS: Eighty-eight patients with a diagnosis of stage III or IV vestibular schwannoma were managed surgically from January 2000 to December 2005 in our department. Six schwannomas were deemed to be cystic according to the following criteria: a voluminous cystic component with mass effect causing symptoms as well as radiological and intraoperative identification of cystic elements. RESULTS: Complete tumor removal was achieved in two patients. After a follow-up of 5 and 7 years, these patients were asymptomatic. In four cases, we performed cyst drainage. For three patients, we implanted a permanent cystoperitoneal shunt. These patients were asymptomatic with a mean follow-up of 19.7 months. CONCLUSIONS: The cystoperitoneal shunt with no valve is a valid palliative surgical solution to remove brain stem compression. Neuronavigation allows proper positioning of the drain and secures the procedure.

[Atypical laryngo-tracheal post-intubation complications: three case reports]. / Complications laryngo-trachéales post-intubation atypiques: à propos de 3 cas.

Endotracheal intubation can induce iatrogenic laryngeal and tracheal complications, particularly when the intubation lasts for a long time. The ENT pratician's job is not only to cure the laryngeal sequelaes but also to prevent and diagnose them. Authors report three atypical cases of laryngeal and tracheal post-intubation complications (laryngeal bilateral immobility, interarythenoidal synechia, oesotracheal fistulae) and discuss them regarding medical literature data.

Phosphoproteomic analysis of Syk kinase signaling in human cancer cells reveals its role in cell-cell adhesion.

The spleen tyrosine kinase Syk has predominantly been studied in hematopoietic cells in which it is involved in immunoreceptor-mediated signaling. Recently, Syk expression was evidenced in numerous nonhematopoietic cells and shown to be involved in tumor formation and progression. The Syk downstream signaling effectors in nonhematopoietic cells remain, however, to be uncovered, and were investigated using MS-based quantitative phosphoproteomics. Two strategies, based on the inhibition of the Syk catalytic activity and on the loss of Syk expression were employed to identify phosphotyrosine-dependent complexes. Quantitative measurements were obtained on 350 proteins purified with phosphotyrosine affinity columns using the SILAC method. Forty-one proteins are dependent on both Syk expression and catalytic activity and were selected as signaling effectors. They are involved in a variety of biological processes such as signal transduction, cell-cell adhesion and cell polarization. We investigated the functional involvement of Syk in cell-cell adhesion and demonstrated the phosphorylation of E-cadherin and alpha-catenin. In addition, Syk is localized at cell-cell contacts, and Syk-mediated phosphorylation of E-cadherin seems to be important for the proper localization of p120-catenin at adherens junctions. Identification of the biochemical pathways regulated by Syk in human cancer cells will help to uncover its role in tumor formation and progression.

[Long-term results of facial palsy's rehabilitation by end-to-end hypoglossal-facial anastomosis]. / Résultats à long terme de la réhabilitation des paralysies faciales périphériques par anastomose hypoglosso-faciale termino-terminale.

OBJECTIVE OF THE STUDY: To evaluate the long term functional and esthetical results of the patients who underwent a facial palsy rehabilitation surgery by a hypoglossal-facial anastomosis. PATIENTS AND METHODS: In this retrospective study, 11 patients (8 males and 3 females) with a complete facial palsy (grade VI House-Brackmann) due to an otoneurosurgery performed between 1985 and 2006 (6 vestibular schwannomas, 1 facial schwannoma of the geniculate ganglion and 4 meningiomas) were evaluated (with the help of an auto-questionnary, a physical exam and electromyography) between July and september in 2008. RESULTS: The voluntary palpebral closure was obtained in 8 cases out 11 (grade III of House-Brackmann). The lingual hemiatrophy was constant. It was major for the patients who didn't take part in a specific re-education. In these cases patients had troubles during feeding and elocution. CONCLUSION: The hypoglossal-facial is a dynamic surgical rehabilitation of choice for the facial palsy. It nearly achived 80% of good palpebral results. The end-to-end anastomosis gives a lingual hemiatrophy which is not the case with a side to end anastomosis. This atrophy can be reduced with an intensive and specific reeducation. Moreover this re-education improves the functionnal and the esthetical results for the patients who underwent an hypoglossal-facial anastomosis. This lingual hemiatrophy was then responsible for troubles for feeding and elocution.

[Cat scratch disease: a diagnosis to be aware of!]. / Maladie des griffes du chat: un diagnostic a ne pas méconnaître!

Subacute cervical lymphadenopathy among young adults may be of an infectious or malignant aetiology. We report two cases of young males with chronic cervical lymphadenopathy. A diagnosis of Cat scratch disease (CSD) was made by serological and molecular studies. CSD is one of the most frequent infectious lymphadenopathies among young people. Diagnosis of CSD is dependent on clinical, epidemiological, molecular and histological criteria. The detection of antibodies to Bartonella Henselae and the amplification of its DNA by Polymerase Chain Reaction (PCR) are the two main methods of laboratory diagnosis. The evolution of CSD is usually benign; however therapeutic management remains problematic, particularly in atypical forms.

[Positron emission tomography in head and neck squamous cell carcinomas]. / La tomographie par émission de positons dans les carcinomes épidermoïdes de la tête et du cou.

18F-Fluorodeoxyglucose positron emission tomography (PET) is an imaging modality which is becoming increasingly esential in oncology, especially in the management of head and neck squamous cell carcinomas (SCC). The most common uses of the PET are listed in this thematic study: initial staging, cervical lymph node metastases from an unknown primary tumor and post-therapeutic follow-up. The advantages and drawbacks of this imaging tool are exposed here according to both our experience and data from the literature. Decision schemes are suggested for each use so as to optimize the use of this imaging modality in the management of these SCC. Other fields of application for the PET are mentioned, such as the in-progress evaluation of response to chemotherapy, the interest of this imaging tool in radiotherapy as well as current biochemical developments concerning new tracers.

Cryopreservation of Crassostrea gigas vesicular cells: viability and metabolic activity.

Cryopreservation is widely used for long-term conservation of various tissues, embryos or gametes. However, few studies have described cryopreservation of invertebrate primary cell cultures and more particularly of marine invertebrate somatic cells. This technique would however be of great interest to facilitate the study of various metabolic processes which vary seasonally. The aim of the present study was to develop a protocol for cryopreservation of Crassostrea gigas vesicular cells. Different parameters were adjusted to improve recovery of cells after freezing. The most efficient cryoprotectant agent was a mix of Me(2)SO, glycerol, and ethylene glycol (4% each). The optimal cooling rate was -1 degrees Cmin(-1) down to -70 degrees C before transfer into liquid nitrogen. In these conditions the percentage of viable cells reached 70% of the control. The glucose metabolism of thawed cells was evaluated using radioactive glucose as a tracer. Immediately after thawing, glucose uptake involving membrane transporters was greatly reduced (24% of control) whereas glucose incorporation into glycogen was less affected (68% of control).

'Suicide' of crickets harbouring hairworms: a proteomics investigation.

Despite increasing evidence of host phenotypic manipulation by parasites, the underlying mechanisms causing infected hosts to act in ways that benefit the parasite remain enigmatic in most cases. Here, we used proteomics tools to identify the biochemical alterations that occur in the head of the cricket Nemobius sylvestris when it is driven to water by the hairworm Paragordius tricuspidatus. We characterized host and parasite proteomes during the expression of the water-seeking behaviour. We found that the parasite produces molecules from the Wnt family that may act directly on the development of the central nervous system (CNS). In the head of manipulated cricket, we found differential expression of proteins specifically linked to neurogenesis, circadian rhythm and neurotransmitter activities. We also detected proteins for which the function(s) are still unknown. This proteomics study on the biochemical pathways altered by hairworms has also allowed us to tackle questions of physiological and molecular convergence in the mechanism(s) causing the alteration of orthoptera behaviour. The two hairworm species produce effective molecules acting directly on the CNS of their orthoptera hosts.

Acute laryngeal paralysis induced by the migration of a totally implantable venous access device's catheter tip.

The authors report a case of acute vagus nerve paralysis that appeared during a course of chemotherapy. The drugs had been administered through a totally implantable venous access device (TIVAD), whose catheter tip had migrated into the right internal jugular vein (IJV) and was surrounded by a complete venous thrombosis. The supposed aetiology of this paralysis was a leakage of the cytotoxic drug (5-fluorouracil) from the vessel wall into the surrounding carotid space, because of the stagnation of the chemotherapeutic agent above the thrombosis. Four months after cessation of chemotherapy, the laryngeal paralysis was still evident.

[Postoperative quality of life for patients with a vestibular schwannoma]. / Qualité de vie chez les patients opérés d'un schwannome vestibulaire.

OBJECTIVES: To determine the prognoses criteria of quality of life's impairment after vestibular schwannoma surgery. STUDY DESIGN: Our study includes retrospectively 104 consecutive patients operated between 1991 & 2000 of a vestibular schwannoma. Patients with bilateral tumors were not included, neither patients lost of follow-up. The french version of the Short Form-36 self assessment questionnaire was sent to all patients. RESULTS: The response rate was 68% (71 patients). The patients' postoperative quality of life was lower of the norm, especially for psychical dimensions. This impairing of health whatever age, tumor size, operative approach or follow-up time. Sex and 2nd surgery were the only factors associated with a lower score. Women had worse rating of physical functioning. CONCLUSION: To operate small tumors should not assume that the impact on patients'life would be necessary less than following the removal of larger tumors. Women should have particularly clear explications before surgery and while follow-up.

Influence of cryoprotective agent and cooling rate on frozen and thawed hemocytes from the Mollusk Haliotis tuberculata.

Cultures of circulating cells from abalone (Haliotis tuberculata) may be used in fundamental research or in biotechnology. This paper describes attempts to develop a cryoconservation method for these hemocytes in order to constitute a standardized cell stock. Among a panel of five distinct cryoprotective solutions, 10% v/v glycerol ('G solution') was the most effective and better post-thaw recovery was achieved after cooling at 1 degrees C/min than after more rapid cooling (3 degrees C or 9 degrees C/min). In 2-day-old cultures, cell viability, assessed by DNA or protein content, was 83 and 78%, respectively, and metabolic activity, measured by the MTT reduction assay, reached 96%. Viability rates were only slightly reduced after 6 days of culture, suggesting a low proportion of damaged cells among the surviving hemocytes. This study identified a cryoprotective solution and a freezing protocol that allow thawed hemocytes to recover a large part of their viability.

[Susac syndrome or microangiopathy of the cochlea, brain and retina]. / Syndrome de Susac ou microangiopathie cochléo-encéphalo-rétinienne.

OBJECTIVES: Susac syndrome, also called SICRET syndrome (small infarction of cochlear, retinal, and encephalic tissue) is a rare condition difficult to diagnose. Sudden deafness may be the inaugural sign. MATERIAL AND METHODS: A female patient developed subacute encephalopathy, bilateral sensorineural hearing loss, and ischemic retinopathy. The patient was given cyclophosphamid and methylprednisolone for six months, followed by prednisone for eight months. RESULTS: Signs of encephalopathy had totally regressed by month 14 and retinal arteries were free of obstruction. Deafness remained unchanged. CONCLUSION: Diagnosis of this microangiopathy involving the inner ear, the brain, and the retina is suggested by the clinical triad and established on the basis of tonal audiometry, fundus examination, fluorescein angiography, examination of the cerebrospinal fluid, magnetic resonance imaging. Multiple sclerosis is the main differential diagnosis. The pathogenesis remains unknown. We observed transient-evoked otoacoustic emissions. There is no consensus concerning treatment. Many advocate combining corticosteroids and immunosuppressors. Otolaryngologists should be aware that an ophthalmological examination is required for patients with central or visual disorders associated with hearing loss.

[Current aspects of laryngeal tuberculosis: a report of four cases]. / Aspects actuels de la tuberculose laryngée. A propos de 4 cas.

OBJECTIVE: Laryngeal tuberculosis is a rare condition. This new clinical pattern of tuberculosis should be recognized by clinicians. METHODS: We report our experience with four cases of laryngeal tuberculosis. RESULTS: The principal differences in the disease pattern are an increase in the number of cases of primary laryngeal tuberculosis without any evident pulmonary involvement and the declining number of pseudotumor forms with an larger number of nonspecific laryngeal localizations. CONCLUSION: Tuberculosis should be entertained as a possible diagnosis in patients with nonspecific laryngeal disease. The diagnosis is confirmed by identification of granulomatous inflammation and acid-fast bacilli. New culture techniques and molecular biology methods such as polymerase chain reaction allow early identification of Mycobacterium tuberculosis.

Cryopreservation of mantle dissociated cells from Haliotis tuberculata (Gastropoda) and postthawed primary cell cultures.

Dissociated mantle cells from the gastropod mollusc Haliotis tuberculata were cultured after a freezing-thawing procedure using either 10% dimethyl sulfoxide (Me(2)SO) or 10% glycerol (Gly) as a cryoprotector. The survival rate of 2-day-old cultured cryopreserved cells after thawing, based on analysis of DNA and protein contents, was nearly 80% in comparison with 2-day-old cultured fresh cells. Cells thawed after cryopreservation exhibited the maintenance of all tested physiological activities. Metabolic activity (measured by the MTT test) and the activity of alkaline phosphatase (a plasma membrane-bound enzyme) were not decreased in comparison to those in cultured fresh cells. In addition, cryopreserved cultured cells maintained a physiological stimulation ability in response to treatment with growth factors. These results taken together represent one of the most convincing demonstrations of the survival and of the recovery of intact functional activities of molluscan cells after a freeze-thawing procedure. Our results suggest that in the future primary cultures of cryopreserved mantle cells will be able to be used for fundamental research, in toxicity tests, or in the field of biotechnology.

[Cephalic vein access for implantable venous access devices. Technique and long-term follow-up]. / Veine céphalique et chambre à cathéter implantable. Technique et suivi à long terme.

OBJECTIVE: To evaluate 1) the advantages and drawbacks of the cephalic vein access for totally implantable venous access devices (TIVAD); 2) the complications of such devices at long-term follow-up. PATIENTS AND METHODS: A retrospective study of a series of 107 cephalic vein accesses attempted on 105 patients from January 1997 to December 2001, in our department. They were 87 men and 18 women, aged from 25 to 85 years (mean: 59). The authors evaluated in each case the surgical technique, the preoperative incidents, the side of surgery, and the short-term and long-term complications. The total follow-up reached 41 284 days. RESULTS: The cephalic vein access attempt failed in 12 cases (11%). These failures were due to intravenous blockade of the flexible catheter or to misroutine of the catheter in 5 cases and to a too thin vein in 7 cases. There was no statistically significant difference between the right and left sides. There was no technique-related complication. There were 18 postoperative complications (19%) out of the 95 devices that were implanted: 6 venous thrombosis, 7 infections, 4 catheter disconnections including 3 intra-cardiac migrations, 1 catheter occlusion. In 12 of these cases, the whole device had to be withdrawn. In the whole series, the devices were withdrawn at mean of 435 days after implantation. CONCLUSION: The use of a TIVAD is necessary when a chemotherapy must be delivered for treatment of a cancer. Cephalic vein access appears to be easy, quick and relatively safe. Postoperatively, serious complications can be encountered like with any type of TIVAD. These complications must be well-known if one wants to manage them well.