Downregulation of ceramide synthase-6 during epithelial-to-mesenchymal transition reduces plasma membrane fluidity and cancer cell motility.

Epithelial-to-mesenchymal transition (EMT) promotes cell motility, which is important for the metastasis of malignant cells, and blocks CD95-mediated apoptotic signaling triggered by immune cells and chemotherapeutic regimens. CD95L, the cognate ligand of CD95, can be cleaved by metalloproteases and released as a soluble molecule (cl-CD95L). Unlike transmembrane CD95L, cl-CD95L does not induce apoptosis but triggers cell motility. Electron paramagnetic resonance was used to show that EMT and cl-CD95L treatment both led to augmentation of plasma membrane fluidity that was instrumental in inducing cell migration. Compaction of the plasma membrane is modulated, among other factors, by the ratio of certain lipids such as sphingolipids in the membrane. An integrative analysis of gene expression in NCI tumor cell lines revealed that expression of ceramide synthase-6 (CerS6) decreased during EMT. Furthermore, pharmacological and genetic approaches established that modulation of CerS6 expression/activity in cancer cells altered the level of C16-ceramide, which in turn influenced plasma membrane fluidity and cell motility. Therefore, this study identifies CerS6 as a novel EMT-regulated gene that has a pivotal role in the regulation of cell migration.

Search for dinucleon decay into kaons in Super-Kamiokande.

A search for the dinucleon decay pp → K+ K+ has been performed using 91.6 kton·yr data from Super-Kamiokande-I. This decay provides a sensitive probe of the R-parity-violating parameter λ112''. A boosted decision tree analysis found no signal candidates in the data. The expected background was 0.28±0.19 atmospheric neutrino induced events and the estimated signal detection efficiency was 12.6%±3.2%. A lower limit of 1.7×10(32) years has been placed on the partial lifetime of the decay O16 → C14K+ K+ at 90% C.L. A corresponding upper limit of 7.8×10(-9) has been placed on the parameter λ112''.

Death receptors as targets in cancer.

UNLABELLED: Anti-tumour therapies based on the use pro-apoptotic receptor agonists, including TNF-related apoptosis-inducing ligand (TRAIL) or monoclonal antibodies targeting TRAIL-R1 or TRAIL-R2, have been disappointing so far, despite clear evidence of clinical activity and lack of adverse events for the vast majority of these compounds, whether combined or not with conventional or targeted anti-cancer therapies. This brief review aims at discussing the possible reasons for the lack of apparent success of these therapeutic approaches and at providing hints in order to rationally design optimal protocols based on our current understanding of TRAIL signalling regulation or resistance for future clinical trials. LINKED ARTICLES: This article is part of a themed section on Emerging Therapeutic Aspects in Oncology. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-8.

Guideline on the design and conduct of cystic fibrosis clinical trials: the European Cystic Fibrosis Society-Clinical Trials Network (ECFS-CTN).

We describe the rationale for disease specific research networks in general as well as the aims and function of the European Cystic Fibrosis Society-Clinical Trials Network (ECFS-CTN) specifically. The ECFS-CTN was founded in 2009 with the aim of improving the quality and quantity of clinical research in the area of cystic fibrosis (CF) in Europe. A network of 18 clinical trial sites in 8 European countries was established according to uniform state-of-the-art quality criteria. To support the ECFS-CTN in the acquisition, planning and conduct of clinical trials, the network is equipped with a coordinating centre, steering and executive committees, and committees for protocol review, standardization, training and networking as well as a data safety monitoring board. A strong partnership with European CF patient parent organizations aims to increase awareness of the need for efficient clinical research and the participation of patients in clinical trials.

Search for differences in oscillation parameters for atmospheric neutrinos and antineutrinos at Super-Kamiokande.

We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) and is consistent with the overall Super-K measurement.

[Is bariatric surgery in adolescents appropriate?]. / La chirurgie bariatrique chez l'adolescent est-elle légitime?

Current recommendations for bariatric surgery are limited to patients older than 18 years. Two studies in 2007 showed that bariatric surgery improves survival in adults. Medical management of severe obesity in adolescents is all too often ineffective. For these reasons, early surgical intervention for adolescents with morbid obesity may be expected to prevent or avoid comorbidities, decrease mortality, and improve the quality of life. Several studies have demonstrated the feasibility of adolescent bariatric surgery with morbidity comparable to that seen in adult series. The earlier the surgery, the better the result in terms of prevention or reversal of comorbid conditions. In the USA, a consensus definition of adolescents eligible for bariatric surgery specifies attainment of Tanner Stage IV of sexual maturity and achievement of 95% of axial growth. Just as in adults, bariatric surgery in adolescents requires prolonged follow-up; it is important that such surgery be performed in centers specialized in adult bariatric surgery having the necessary multidisciplinary structure.

Search for proton decay via p-->e+pi0 and p-->micro+pi0 in a large water Cherenkov detector.

We have searched for proton decays via p-->e;{+}pi;{0} and p-->micro;{+}pi;{0} using data from a 91.7 kt.yr exposure of Super-Kamiokande-I and a 49.2 kt.yr exposure of Super-Kamiokande-II. No candidate events were observed with expected backgrounds induced by atmospheric neutrinos of 0.3 events for each decay mode. From these results, we set lower limits on the partial lifetime of 8.2 x 10;{33} and 6.6 x 10;{33} years at 90% confidence level for p-->e;{+}pi;{0} and p-->micro;{+}pi;{0} modes, respectively.

A "self adhering" prosthesis for hernia repair: experimental study.

BACKGROUND: Prosthetic reinforcement is now routine in the management of inguinal and incisional hernia, and it significantly reduces the risk of recurrence. After surgery, chronic pain is often attributed to the characteristics of the mesh and to the method of fixation in the wound, with a potential risk of nerve or muscle injuries. AIM: To evaluate the properties of a new "self adhering" prosthesis in an experimental animal study. MATERIALS AND METHODS: The self adhering prosthesis, a lightweight (40 mg/m(2)) polypropylene mesh coated with a synthetic glue on one side, was implanted laparoscopically in pigs. Removal of the prosthesis was performed at one day, one week and one month post operatively. A macroscopic and microscopic evaluation was performed. The results, using a quantitative score, were compared to those of a control group using the same polypropylene mesh without glue, but fixed by staples. RESULTS: The operative time was significantly lower in the self adhering group: 23 min (15-32) versus 31 min (21-40) (P = 0.01). The average time interval from the introduction of the mesh into the preperitoneal space until the appearance of the first tough adhesion was 3 min (2-4). In the control group, the mesh handling time was 8.3 min (5-14) (P = 0.01). At the time of implantation, the score was at a maximum value in all cases for the self adhering prostheses, especially concerning handling and adhesiveness. Upon removal, this score was noted to be good or very good in 90-100% of the cases. There was a good integration in the muscle confirmed histologically, and there was no shrinkage, no mobilisation and no migration. At one month, the thickness of the fibrosis at the limits of the meshes was significantly higher for the self adhering prostheses (P = 0.02). CONCLUSION: In this experimental study, the self adhering prosthesis demonstrated its adhesive properties and its ability to be well tolerated, with a good macroscopic and microscopic integration into the abdominal wound. This should allow us to perform a clinical prospective study in an open and laparoscopic approach with the double objective of reducing post operative pain induced by mechanical fixation and decreasing the cost of these procedures by reducing the operative time and by eliminating staple fixation.

[Evaluation of stress in surgical trainees: prospective study of heart rate during laparoscopic cholecystectomy]. / Stress des chirurgiens en formation: Etude prospective de la cardio-fréquence lors de cholécystectomies laparoscopiques.

INTRODUCTION: Surgical training is stressful, particularly in the operating room setting. The purpose of the study is to evaluate and quantitate intra-operative stress in surgical trainees. MATERIAL: and methods: Cardiac rate was used as a measure of stress during surgical cases; surgical residents serving as the primary surgeon and assistant during 21 laparoscopic cholecystectomies underwent telemetry monitoring. RESULTS: Intra-operative cardiac rate increased by 4-10%, particularly in the resident serving as primary surgeon. The most stressful moments of the procedure were the draping of the surgical field, trocar placement, clip application, and extraction of the gallbladder. CONCLUSION: This study offers a measure of the stress of surgical residents in the operating room. Heart rate is not the ideal parameter of stress, yet it gives a good idea of the level of stress. The identification of stress-inducing factors may help residents to deal with difficult situations.

[Value of the informed consent in digestive surgery? Prospective study 259 cases]. / Le consentement éclairé: quelle est sa valeur en chirurgie digestive? Etude prospective sur 259 cas.

SITUATION: In 1997 the Supreme Court of Justice decreed that "the doctor is responsible for giving his patient certain information and is obliged to prove that the information has been given". French surgical societies recommend using a form of informed consent signed by the patient applicable to all practices. AIMS: To evaluate a step taken systematically since 1999 in our department. PATIENTS AND METHODS: A prospective study was put into place for 259 patients candidate for elective surgery. All patients signed and returned the "informed consent" before surgery. The day of leaving the hospital, they answered a post-operative questionnaire to evaluate what they remembered of the "informed consent form" and the quality of information. RESULTS: Ninety three per cent of them remembered it. Eight per cent signed it without reading it. Eighty two per cent of the patients think that this document is useful for their medical records. Among the patients who did not read the informed consent form: 38% wished it gave more information, whereas only 16% of those who had read it, considered the given information inadequate. This difference is statistically (p=0.03) significant. CONCLUSION: The informed consent form gives a lot of information to the patients, but the surgeon is still obliged to do likewise. Patients who did not read the consent were less satisfied with the given information than those who had read it. The positive reaction of the patients in favour of the form makes it evident that the existence of the form reassures them.

Measurement of atmospheric neutrino flux consistent with tau neutrino appearance.

A search for the appearance of tau neutrinos from nu(mu) <--> nu(tau) oscillations in the atmospheric neutrinos has been performed using 1489.2 days of atmospheric neutrino data from the Super-Kamiokande-I experiment. A best fit tau neutrino appearance signal of 138+/-48(stat)-32(+15)(syst) events is obtained with an expectation of 78+/-26(syst). The hypothesis of no tau neutrino appearance is disfavored by 2.4 sigma.

Trans-metastasis hepatectomy: results of a 21-case study.

AIM: The aim of this study was to report the feasibility and efficiency of a new approach, called post-RF trans-metastasis hepatectomy (PRFTMH). This technique consists in using RF to first ablate an ill-located liver metastasis (LM) along the planned hepatectomy resection line, the only one possible for volumetric reasons, and then to perform the hepatectomy passing via this initially ablated LM. MATERIAL AND METHODS: Twenty-one patients were treated with PRFTMH between January 2000 and May 2004. Thirteen of them had a primary colorectal tumour, four had a primary endocrine tumour and four had miscellaneous primaries. The mean number of LMs per patient was 13.8 (10.7 for primary colorectal tumours and 22.2 for primary endocrine tumours). Pre-operative hypertrophy of the future remaining liver was obtained by selective portal vein embolisation in 11 patients. RESULTS: One patient died post-operatively (4.7%) and five developed complications (24%). No local recurrence has occurred at the site of PRFTMH after a median follow-up of 19.4 months (range: 47-7), demonstrating the efficacy of this technique. All patients, except the patient who died post-operatively, are currently alive, and the median survival rate has not yet been attained, after a median follow-up of 19.4 months. CONCLUSION: PRFTMH combining RF ablation and trans-metastasis hepatectomy is a new and safe technique, allowing a curative approach to be proposed to some patients with unresectable bilateral LMs.

Metabolic approach of absence seizures in a genetic model of absence epilepsy, the GAERS: study of the leucine-glutamate cycle.

We suggest that a dysregulation of energy metabolism in the brain of genetic absence epilepsy rats from Strasbourg (GAERS) could create a specific cerebral environment that would favor the expression of spike-and-wave discharges (SWD) in the thalamocortical loop, largely dependent on glutamatergic and gamma-aminobutyric acid (GABA)-ergic neurotransmissions. We tested several aspects of metabolic activity in the brain of GAERS compared to a genetic strain of nonepileptic (NE) rats. Glucose metabolism was higher in all brain regions of GAERS compared to those of NE rats along the whole glycolytic and aerobic pathways, as assessed by regional histochemical measurement of lactate dehydrogenase and cytochrome oxidase activities. Branched-chain amino acids (BCAA) and alpha-ketoisocaproate (alpha-KIC), the ketoacid of leucine, when injected intraperitoneally, increased the number of SWD in GAERS but had only a slight effect on their duration. These data speak in favor of a BCAA- or alpha-KIC-induced change in neuronal excitability. Leucine and alpha-KIC decreased the concentration of glutamate in thalamus and cortex without affecting GABA concentrations. Thus, BCAA and alpha-KIC, by decreasing glutamatergic neurotransmission, could favor GABAergic neurotransmission, which is known to increase the occurrence of seizures in GAERS. Finally, the transport of [1-(14)C]alpha-KIC in freshly isolated cortical neurons was lower in GAERS than in NE rats, and this difference was shown to be of metabolic origin. The addition of gabapentin, a specific inhibitor of BCAA transaminase (BCAT), reduced the transport of [1-(14)C]alpha-KIC in GAERS and NE rats to a level that became identical in both strains. This strain-dependent change was not related to a difference in the activity of BCAT, which was identical in GAERS and NE rats. The exact origin of this apparent metabolic dysregulation of energy metabolism in GAERS that could underlie the origin of seizures in that strain remains to be explored further.

Modulation of absence seizures by branched-chain amino acids: correlation with brain amino acid concentrations.

The occurrence of absence seizures might be due to a disturbance of the balance between excitatory and inhibitory neurotransmissions in the thalamo-cortical loop. In this study, we explored the consequences of buffering the glutamate content of brain cells on the occurrence and duration of seizures in Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a genetic model of generalized non-convulsive epilepsy. Branched-chain amino acids (BCAAs) and alpha-ketoisocaproate (alpha-KIC), the ketoacid of leucine were repeatedly shown to have a critical role in brain glutamate metabolism. Thus, GAERS were injected by intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) route with these compounds, then the effects on seizures were evaluated on the electroencephalographic recording. We also measured the concentration of amino acids in thalamus and cortex after an i.p. injection of leucine or alpha-KIC. Intracerebroventricular injections of leucine or alpha-KIC did not influence the occurrence of seizures, possibly because the substances reached only the cortex. BCAAs and alpha-KIC, injected intraperitoneally, increased the number of seizures whereas they had only a slight effect on their duration. Leucine and alpha-KIC decreased the concentration of glutamate in thalamus and cortex without affecting GABA concentrations. Thus, BCAAs and alpha-KIC, by decreasing the effects of glutamatergic neurotransmission could facilitate those of GABAergic neurotransmission, which is known to increase the occurrence of seizures in GAERS.

Modulation of pentylenetetrazol-induced seizure activity by branched-chain amino acids and alpha-ketoisocaproate.

Branched-chain amino acids, and mainly leucine act as nitrogen donors in the cerebral glutamate-glutamine cycle, thereby reducing brain excitability. Rats equipped with cortical electrodes received 300 mg/kg of leucine, isoleucine, valine or the ketoacid of leucine, alpha-ketoisocaproate at 2 h before the induction of seizures by 40 mg/kg pentylenetetrazol. Control groups received saline or a commercial mixture of amino acids, Vamine(R). Leucine and isoleucine increased the latency to absence-like and tonic-clonic seizures but did not influence the duration of the tonic-clonic seizure. Vamine(R), valine and alpha-ketoisocaproate had no effect. These data are consistent with the role of leucine in buffering brain glutamate concentration.

Increased cathepsin D level in the serum of patients with metastatic breast carcinoma detected with a specific pro-cathepsin D immunoassay.

BACKGROUND: An increased cathepsin D (cath-D) level in breast carcinoma cytosol has been proposed as a prognostic parameter. However, no increase had been previously detected in serum when assaying total cath-D concentration. METHODS: The authors compared 2 radioimmunoassays of total cath-D and pro-cath-D in the serum of 3 groups of patients: those with metastatic breast carcinomas (n = 30), those with nonmetastatic breast carcinomas (n = 24), and healthy women (n = 21). RESULTS: There was a significant increase of total cath-D and pro-cath-D in the serum of 18 of the 30 patients with metastatic breast carcinoma. No increase was observed in any of the patients with nonmetastatic disease compared with healthy women. Moreover, the level of pro-cath-D was often superior to that of total cath-D in the same patients, suggesting that the total cath-D assay in serum underestimates the actual concentration of pro-cath-D. This is not believed to be due to the masking of cath-D with the circulating mannose-6-phosphate/insulin-like growth factor II receptor because the purified receptor did not interfere in the binding of the monoclonal antibodies used in the assay to cath-D. CONCLUSIONS: An increased level of cath-D in the serum of breast carcinoma patients is a late event observed only in patients with metastatic disease. This increased circulating level is more likely due to increased secretion of the proenzyme rather than to tumor cell lysis.

Isolation of 10 differentially expressed cDNAs in p53-induced apoptosis: activation of the vertebrate homologue of the drosophila seven in absentia gene.

We report the isolation of 10 differentially expressed cDNAs in the process of apoptosis induced by the p53 tamor suppressor. As a global analytical method, we performed a differential display of mRNA between mouse M1 myeloid leukemia cells and derived clone LTR6 cells, which contain a stably transfected temperature-sensitive mutant of p53. At 32 degrees C wild-type p53 function is activated in LTR6 cells, resulting in programmed cell death. Eight genes are activated (TSAP; tumor suppressor activated pathway), and two are inhibited (TSIP, tumor suppressor inhibited pathway) in their expression. None of the 10 sequences has hitherto been recognized as part of the p53 signaling pathway. Three TSAPs are homologous to known genes. TSAP1 corresponds to phospholipase C beta 4. TSAP2 has a conserved domain homologous to a multiple endocrine neoplasia I (ZFM1) candidate gene. TSAP3 is the mouse homologue of the Drosophila seven in absentia gene. These data provide novel molecules involved in the pathway of wild-type p53 activation. They establish a functional link between a homologue of a conserved developmental Drosophila gene and signal transduction in tumor suppression leading to programmed cell death.

[Cellular senescence and survival of T lymphocytes]. / Sénescence cellulaire et survie des lymphocytes T.

In order to study cellular senescence in T lymphocytes and its link with aging, we have undertaken long-term cultures from adult individuals (aged from 20 to 40) and centenarians. The proliferative advantage of CD4+ over CD8+ T cells is reversed after the second stimulation. Periodically stimulated cultures remained exponentially growing during nearly 200 days, whereas 2 of them that were continued for 300 days stopped proliferating. However, once this phase of senescence is reached, the cells do not die out. Six other cultures remained viable for 34 months without proliferation but with conservation of the cell number. Three of these cultures have clonal karyotypic abnormalities: trisomy 2 and telomeric fusions.

Increased synthesis of extracellular spleen glycosaminoglycans in an experimental myeloproliferative syndrome.

The changes occurring in the hematopoietic extracellular matrix in an experimental myeloproliferative syndrome were explored by comparing the glycosaminoglycan (GAG) composition of normal mouse spleens and spleens infected with myeloproliferative sarcoma virus (MPSV). Large quantities of hyaluronate and of sulfated GAGs accumulated in the extracellular matrix of infected spleens, as shown by histoimmunoassay and alcian blue staining, respectively. The splenic GAGs were either labeled with 35S-sulfate injected in vivo or unlabeled. The spleens were fractionated to separate hematopoietic cells from the stromal component containing extracellular matrix material and fibroblasts, and the GAGs were extracted from each fraction. Specific degradative treatments and electrophoresis indicated that sulfated GAGs were mostly chondroitin sulfate and heparan sulfate. Three hours after in vivo injection of 35S-sulfate, the amount of 35S-GAGs was increased approximately fivefold per mg stromal proteins. The bulk of these 35S-GAGs (70%) was recovered in the stromal fraction. The higher amount of sulfated GAGs in leukemic spleen was due both to the presence of more producer cells (infected fibroblasts and hematopoietic cells) and to a stimulation of GAG synthesis per cell, as evidenced 35S-labeling in in vitro experiments. Chondroitin sulfate was the main sulfated GAG present in the culture medium of both hematopoietic and fibroblastic cells and in the pericellular material released by trypsin from fibroblastic cells. High amounts of chondroitin sulfate, which has a possible role in the detachment of hematopoietic cells from the stromal cells, may favour the release of hematopoietic cells from the spleen into the peripheral blood. Heparan sulfate was produced by fibroblastic cells and it was principally present in their pericellular material. Considering the capacity of heparan sulfate to retain cytokines, as demonstrated by others in vitro, large amounts of heparan sulfate may result in the retention of large amounts of the cytokines, which production is enhanced in the infected spleen. This phenomenon may contribute to promote the hematopoietic stem cell proliferation characteristic of the MPSV-induced myeloproliferative disease.