Transition kinetics of mixed lipid:photosurfactant assemblies studied by time-resolved small angle X-ray scattering.

HYPOTHESIS: Photoswitchable surfactants are used in the design of many light-responsive colloids and/or self-assemblies. Photo-isomerization enables to control molecular equilibrium, and triggers transient reorganizations with possibly out-of-equilibrium intermediate states that have been overlooked. Here, we address this question by an in depth structural investigation of intermediate lipid-surfactant assemblies that occur during fast isothermal photo-triggered transition in lipid:surfactant mixtures. EXPERIMENTS: The structural parameters of mixed assemblies of azobenzene-containing cationic surfactant (AzoTMA) and dioleoylphosphatidylcholine (DOPC) lipids were studied by light scattering and time-resolved small angle X-ray scattering. Structural and compositional information about the assemblies and unimers in bulk were determined at the photostationary states, as well as at intermediate kinetic states formed during UV or blue light illumination. FINDINGS: DOPC:AzoTMA systems form mixed assemblies representative of phospholipid:cationic surfactant mixtures, that evolve from spheroid, to rod-like micelles, and vesicles with increasing DOPC fraction. Transient assemblies detected during the photo-triggered kinetics are similar to the ones found in stationary states. But changes of AzoTMA unimers in bulk can be considerably faster than mass reorganizations of the mixed assemblies, suggesting that out-of-equilibrium conditions are transiently reached. Mass reorganization of the surfactant-enriched assemblies is much faster than in the lipid enriched ones, providing insight into the role of lipids in a slow reorganization of the assemblies.

Perfusion-weighted techniques in MRI grading of pediatric cerebral tumors: efficiency of dynamic susceptibility contrast and arterial spin labeling.

PURPOSE: Dynamic susceptibility contrast (DSC) and arterial spin labeling (ASL) perfusion MRI are applied in pediatric brain tumor grading, but their value for clinical daily practice remains unclear. We explored the ability of ASL and DSC to distinguish low- and high-grade lesions, in an unselected cohort of pediatric cerebral tumors. METHODS: We retrospectively compared standard perfusion outcomes including blood volume, blood flow, and time parameters from DSC and ASL at 1.5T or 3T MRI scanners of 46 treatment-naive patients by drawing ROI via consensus by two neuroradiologists on the solid portions of every tumor. The discriminant abilities of perfusion parameters were evaluated by receiver operating characteristic (ROC) over the entire cohort and depending on the tumor location and the magnetic field. RESULTS: ASL and DSC parameters showed overall low to moderate performances to distinguish low- and high-grade tumors (area under the curve: between 0.548 and 0.697). Discriminant abilities were better for tumors located supratentorially (AUC between 0.777 and 0.810) than infratentorially, where none of the metrics reached significance. We observed a better differentiation between low- and high-grade cancers at 3T than at 1.5-T. For infratentorial tumors, time parameters from DSC performed better than the commonly used metrics (AUC ≥ 0.8). CONCLUSION: DSC and ASL show moderate abilities to distinguish low- and high-grade brain tumors in an unselected cohort. Absolute value of K2, TMAX, tMIP, and normalized value of TMAX of the DSC appear as an alternative to conventional parameters for infratentorial tumors. Three Tesla evaluation should be favored over 1.5-Tesla.

[Computer-assisted therapy and video games in psychosocial rehabilitation for schizophrenia patients]. / L'utilisation des thérapies assistées par ordinateur et des jeux vidéo à visée thérapeutique dans les soins de réhabilitation psychosociale chez les sujets souffrant de schizophrénie, revue de la littérature.

OBJECTIVES: Video games and virtual reality have recently become used by clinicians for training or information media or as therapeutic tools. The purpose is to review the use of these technologies for therapy destined for schizophrenia patients. METHODS: We conducted a review in October 2016 using Pubmed, Scopus and PsychInfo using the following Medical Subject Headings (MESH): "video games", "virtual reality" and "therapy, computer-assisted/methods", each associated with "schizophrenia". Papers were included in the review if: (a) they were published in an English, Spanish or French-language peer-reviewed journal, (b) the study enrolled patients with schizophrenia or schizo-affective disorder, (c) the patients used a therapeutic video game or therapeutic virtual reality device. RESULTS: Eighteen publications were included. The devices studied are mainly therapeutic software developed specifically for therapeutic care. They can be classified according to their therapeutic objectives. These targets corresponded to objectives of psychosocial rehabilitation: improvement of residual symptomatology, cognitive remediation, remediation of cognition and social skills, improvement of everyday life activities, support for occupational integration. Very different devices were proposed. Some researchers analysed programs developed specifically for patients with schizophrenia, while others were interested in the impact of commercial games. Most of the studies were recent, preliminary and European. The impact of these devices was globally positive, particularly concerning cognitive functions. CONCLUSIONS: Computer-assisted therapy, video games and virtual reality cannot replace usual care but could be used as adjunctive therapy. However, recommending their use seems premature because of the recent and preliminary character of most studies. Moreover, a link is still lacking between this field of research in psychiatry and other fields of research, particularly game studies. Finally, it might be interesting to analyse more precisely the neuropsychological impact of existing commercial games which could potentially be useful for psychosocial rehabilitation.

[Demons and Meigs syndromes and pseudosyndromes today]. / Syndromes et pseudosyndromes de Demons et Meigs aujourd'hui.

There is a total confusion between Demons or Meigs syndromes and pseudosyndromes.The need for greater precision in publications titles has become an emergency. We have analysed 297 observations gathered in litterature from 1904 to 2004. The increase in the number of Meigs pseudosyndromes based on diverse associated condition means that we must include under the name Demons syndrome, as he did himself, all tumours of the female genital tract, providing they are benign, wherever the effusion takes place, reserve the name Demons Meigs because it has been used historically and because it was Meigs wish, solely for fibrothecomas of the ovary and for tumours of the granulosa bring together under the name Demons pseudosyndrome all other non tumoral benign entities. Malignant tumours, with or without malignant cells in the effusions are not pseudosyndromes but authentic neoplastic lesions. An over-lax definition of pseudosyndromes runs the risk of the name simply becoming a catch-all term. On the other hand we can say that 100years later diagnosis is not earlier, a bilateral tumor is not a rarity, mechanisms of effusions genesis remain mysterious and the treatment has been enriched with coeliosurgery.

The occurrence of acidic drugs and caffeine in sewage effluents and receiving waters from three coastal watersheds in Atlantic Canada.

Pharmaceuticals, by design, induce biological responses in animals and humans at very low doses, making their presence in the aquatic environment an issue of concern. Prescription and over-the-counter drugs commonly found in wastewater are discharged on a continuous basis into the waters of two coastal watersheds in Atlantic Canada. Ten acidic drugs and caffeine were observed in the final effluents of sewage treatment facilities in Millcove (Halifax watershed), and Trenton (Pictou watershed), Nova Scotia. Naproxen and ibuprofen, two highly used non-steroidal anti-inflammatory drugs (NSAIDs), and caffeine, were the predominant compounds. Naproxen, ibuprofen, salicylic acid (metabolite of acetylsalicylic acid), diclofenac (NSAID) and gemfibrozil (lipid regulator) were also detected in the low ng/L range in the receiving waters of treated and untreated sewage outflows. Acidic drugs were not detected in the marine waters of the Cocagne watershed located in southeast New Brunswick. This watershed was evaluated for the possibility of contamination of near-shore coastal waters from domestic septic systems in the vicinity of a densely populated cottage area. The observation of traces of caffeine suggests some organic pollution in the area.

Broadband supercontinuum interferometer for high-resolution profilometry.

In this paper, it is shown that a white light supercontinuum source generated in an air-silica microstructured optical fiber pumped with picosecond pulses offers the possibility to improve fringes visibility in interferometric acquisitions. Consequently, this source combined with a spectral interferometer, reaches high-resolution profilometric measurements. Phase calculation based on seven point algorithm can perform theoretically a subnanometer resolution. This method provides a one line profile of large surfaces from the analysis of a single shot image, without any mechanical scanning.

Backscattered speckle size as a function of polarization: influence of particle-size and- concentration.

This report about backscattering measure-ments of the speckle produced by strongly-scattering liquid media shows that the size of the backscattered speckle depends on scattering and anisotropy coefficients. These measurements were aimed at assessing the effects of polarization characteristics of the incident laser beam and of the scattered light on speckle size. The samples under study consisted of monodisperse polystyrene microspheres in solutions, mixtures of different sized-microspheres, milk, blood and pig skin. Such measurements of speckle size in polarization give information on strongly scattering media, allow their discrimination and enable one to characterize the undergone changes.

Scattering through fluids: speckle size measurement and Monte Carlo simulations close to and into the multiple scattering.

We report on measurements in transmission of the speckle produced by scattering liquid media: diluted milk and water solutio ns of polystyrene-microspheres of different diameters. The speckle size is affected not only by scattering parameters such as the optical thickness, but also by the dimensions of the scatters. From the speckle measurement, we propose a method to differentiate media. Moreover, a calculation of the transmitted light profile by Monte Carlo simulation allowed us to get a better insight on the speckle size evolution versus scattering.

Imaging through a scattering medium with an interferential spectrometer by selection of an amplitude modulation correlator.

Low-coherence interferometric systems provide three-dimensional imaging through scattering media by measurement of the object's temporal response. An optical correlator is presented that allows direct recording of the signal issued from the object under reflection. The filtering technique enhances the image visibility and allows one to obtain an image with a good signal-to-noise ratio. The performance of two particular imaging systems, point-to-point and vertical-slice imaging, is discussed with an object comprising two cover plates that are attached.

Impact of a commercial peat moss operation on water quality and biota in a small tributary of the Richibucto River, Kent County, New Brunswick, Canada.

The St-Charles Plain (Kent County, New Brunswick, Canada) commercial peat moss operation has been ongoing since 1983. To process the peat, a dry extraction method is used that requires extensive drainage of the peat bog. The water is directed toward sedimentation ponds, where it drains into a small brook, which feeds into a river affected by tidal salt water. Water discharge from the bog contains large amounts of peat particles that deposit in the surrounding watershed. As a result, the pH of the freshwater sites that receive the drainage water from the commercial operation, is fairly acidic (pH 3.9-4.7). Water samples from or near the peat moss operation have a higher concentration of total phosphorous and total organic carbon. The peat particles contain relatively high levels of total mercury, as reflected by analysis of peat sediments. However, the water samples contained low levels of dissolved mercury. Indigenous samples of biota-namely, sand shrimps (Crangon septemspinosa) and mummichogs (Fundulus heteroclitus)-did not contain mercury levels higher in the impacted sites than in the reference sites. Introduced blue mussels (Mytilus edulis) did not accumulate significant amounts of mercury during a 62-day exposure in the study area. Overall, the data suggest that although relatively large amounts of mercury-containing peat particles are discharged into the ecosystem, bioaccumulation of mercury in the biota does not occur.

Partial combination applied to phylogeny of European cyprinids using the mitochondrial control region.

Previous molecular phylogenies of European cyprinids led to some solid facts and some uncertainties. This study is based on a stretch of more than 1 kb in the mitochondrial control region newly sequenced for 35 European cyprinids and on previous cytochrome b and 16S rDNA data. The trees based on the control region are more accurate and robust than those obtained from the two other genes. Character incongruence among the three genes was tested using the incongruence length difference (ILD) test. Iterative removals of individual sequences followed by new ILD tests identified two sequences responsible for statistically significant incongruence. A partial combination was conducted, that is, a combination of the three data sets, removing the two sequences previously identified. The phylogenetic analysis of this partial combination gives a more robust and resolved picture of subfamilial interrelationships. The Rasborinae are the sister group of all other cyprinids. The monophyletic Cyprininae emerges next. Tinca tinca first and then Rhodeus are the sister groups of all the remaining nonrasborine and noncyprinine species. Gobio is the sister group of the Leuciscinae, in which the Phoxinini are the sister group of the Leuciscini. Within the Leuciscini, the genus Leuciscus and the subfamily Alburninae are both paraphyletic. The Rasborinae are the most basal cyprinid subfamily and the Tincinae are not the sister group of the Cyprininae. These two results challenge only two anatomical characters, which need to be reinterpreted or considered as homoplastic in cyprinid evolution: the modification of the first pleural rib and its parapophysis and the bony composition of the interorbital septum.

High-resolution optical correlation imaging in a scattering medium.

An optical correlation setup is used to image transparent objects through scattering media, and 10-mum longitudinal and 2.5-mum transverse resolution are achieved. Spectral-bandwidth sampling of the light source is made possible by a tunable dye laser and leads to signal enhancement as a result of sampling interferogram filtering. An optical system allows observation of sample slices without the need for a translation stage.

Performance of 18S rDNA helix E23 for phylogenetic relationships within and between the Rotifera-Acanthocephala clades.

The species diversity of the phylum Rotifera has been largely studied on the basis of morphological characters. However, cladistic relationships within this group are poorly resolved due to extensive homoplasy in morphological traits, substantial phenotypic plasticity and a poor fossil record. We undertook this study to determine if a phylogeny based on partial 18S rDNA, which included the helix E23 of 18S rDNA sequence, was concordant with established taxonomic relationships within the order Ploimida (class: Monogononta). We also estimated the level of polymorphism within clones and populations of Ploimida 'species'. Finally, we included the Cycliophora Symbion pandora as outgroup and the variable helix E23 region to examine the influence of their signal on the evolutionary relationships among Acanthocephala, Bdelloidea and Ploimida. Phylogenetic reconstruction was performed using maximum parsimony, neighbour joining and maximum likelihood methods. We found 1) that morphologically similar Ploimida 'species' show vastly different 18S E23 rDNA sequences; 2) inclusion of the helix E23 of 18S rDNA and its secondary structure analysis results in better resolution of family level relationships within the Ploimida; 3) an impact of Symbion pandora as an outgroup with inclusion of the helix E23 on the relationships between the Rotifera and the Acanthocephala; and 4) partial incongruence and differential substitution rate between conserved region and helix E23 region of the 18S rDNA gene depending on the taxomic group studied.

Long-term results and prognostic factors in patients with epithelial ovarian cancer.

OBJECTIVES: The aim of this study was to evaluate long-term results and to assess prognostic factors which have an impact on overall survival in patients with epithelial ovarian cancer. METHODS: A retrospective analysis of 287 patients treated between 1975 and 1995 was performed. All operations were performed by senior surgeons. Histologic sections were reviewed by the same pathologist. Successive adjuvant chemotherapy regimens are described. Survival was evaluated in 1997. Follow-up lasted 25-260 months (median 90). Statistical methods included Kaplan-Meier survival curves, log-rank test, and multivariate analysis. RESULTS: The 5-year survival rates were 76, 42, 21, and 6% for patients with stage I, II, III, and IV disease, respectively. Age, FIGO stage, cytology of ascites, histologic type and grade, extent of surgery, and number of residual tumors were significant prognostic indicators in univariate analysis. Multivariate analysis showed that the risk of mortality according to FIGO stage was 2.8, 95% CI [1.2-6.3], P = 0.01 for FIGO II, 5.6, 95% CI [2.9-10.8], P < 0.001 for FIGO III, and 10.5, 95% CI [4.9-22. 1], P < 0.001 for FIGO IV in comparison with FIGO I. Patients with a serous epithelial carcinoma had a 1.7-fold higher risk of mortality than patients with other histologic types: RR = 1.7, 95% CI [1.1-2. 8], P < 0.001. Patients whose tumors distribution permitted optimal surgery had a 2.3-fold lower risk of mortality than patients treated with sub- or nonoptimal surgery: RR = 0.43, 95% CI [0.29-0.64], P < 0.001. The risk of mortality for patients treated with alkylating agents, platinum-based combination chemotherapy without taxanes, or carboplatin plus paclitaxel regimens compared with patients who did not receive treatment was reduced by 47%, 95% CI [8-69%], P = 0.025, 55%, 95% CI [22-74%], P = 0.005, and 70%, 95% CI [35-86%], P = 0.002, respectively. CONCLUSION: Our study confirms the benefit of cytoreductive surgery and the efficacy of platinum plus paclitaxel first-line chemotherapy which has recently been recognized as the standard treatment for advanced epithelial ovarian cancer.

Unusual regulation of cyclin D1 and cyclin-dependent kinases cdk2 and cdk4 during in vivo mitotic stimulation of olfactory neuron progenitors in adult mouse.

The molecular mechanisms underlying cell cycle control in neuronal progenitors have been investigated with adult mouse olfactory epithelium as a model system. Odor receptive neurons of mammalian olfactory epithelium are short-lived and renewed in the adult by mitotic division of intrinsic neuronal progenitors. Ablation of the synaptic target, olfactory bulb, induces sequentially extensive apoptosis of sensory neurons and then stimulation of progenitor proliferation, peaking at 36 h and 4 days, respectively, postlesion. Known molecular effectors of G1 phase entry have been assessed on protein extracts of olfactory organs sampled at various postbulbectomy times in adult mice. The decay of betaIII-tubulin and olfactory marker protein levels and the rise of proliferating cell nuclear antigen (PCNA) levels, starting 1 and 3 days, respectively, postlesion, provided the kinetic frame of neuronal dynamics. Cyclin D1, cyclin E, and cyclin-dependent kinase cdk2 levels, low in olfactory organ of intact mice, increased 3 days after bulbectomy in parallel with PCNA levels; cdk4 content was initially high and unaffected by lesioning. Western blots of the known cdk inhibitors revealed proliferation-related decreases of p18, p21, and p27 from high expression in intact organs. Immunoprecipitation of cdk2 and cdk4 fractions of protein extracts at 4 days postlesion (mitotic reaction peak) versus control, followed by cyclin D1 immunoblotting, and vice versa, revealed that levels of both cyclin D1/cdk2 and cyclin D1/cdk4 complexes, as well as their kinase activities, were dramatically increased after lesion. In vivo proliferation of olfactory neuronal lineage cells thus involves functional binding of cyclin D1 with cdk2 and cdk4, with differential activation mechanisms for cdk2 and cdk4. In addition, the RT-PCR-detected cyclin D1 mRNA level remained unaffected after bulbectomy, which indicated that the cyclin D1 rise should involve posttranscriptional mechanisms in this in vivo neuronal system. These observations are discussed, along with their relevance to cell cycle control and to olfactory neuron dynamics.

[Prognostic factors for survival of ovarian epithelial cancers: apropos of 287 cases]. / Facteurs pronostiques de survie des cancers épithéliaux de l'ovaire: à propos de 287 cas.

OBJECTIVES: To evaluate survival and assess prognostic factors in patients with epithelial ovarian cancer. METHODS: Retrospective analysis of 287 patients treated between 1975 and 1995. All operations were performed by senior surgeons. Histologic sections were reviewed by the same pathologist. Successive adjuvant chemotherapy regimens are described. Survival was evaluated in 1997. Follow-up lasted 25-260 months (median 90). Statistical methods included Kaplan-Meier survival curves, logrank test and multivariate analysis. RESULTS: The five-year survival rates 76%, 42%, 21% and 6% for patients with stage I, II, III and IV disease, respectively. Age, FIGO stage, cytology of ascites, histologic type and grade, extent of surgery and number of residual tumors were significant prognostic indicators in univariate analysis. Multivariate analysis showed that the risk of mortality was reduced by 57% for patients whose tumor distribution permitted optimal surgery (RR = 0.43, 95% CI [0.29-0.64]; P < 0.001). The risk of mortality according to FIGO stage was 2.8 (95% CI [1.2-6.3]; P = 0.01) for FIGO II, 5.6 (95% CI [2.9-10.8]; P < 0.001) for FIGO III and 10.5 (95% CI [4.9-22.1]; P < 0.001) for FIGO IV in comparison with FIGO I. The risk of mortality for patients treated with alkylating agents, platinum-based combination chemotherapy taxanes or carboplatin plus paclitaxel regimen compared with patients who did not receive treatment was reduced by 47% (95% CI [8%-69%]; P = 0.025), 55% (95% CI [22%-74%]; P = 0.005) and 70% (95% CI [35%-86%]; P = 0.002), respectively. Patients with a serous epithelial carcinoma had a 1.7-fold higher risk of mortality than patients with other histologic types (RR = 1.7, 95% CI [1.1-2.8]; P = 0.02). CONCLUSION: Our study confirms the benefit of cytoreductive surgery and the efficacy of platinum plus paclitaxel first-line chemotherapy, which has recently been recognized as the standard treatment for advanced epithelial ovarian cancer.

FGF7/KGF triggers cell transformation and invasion on immortalised human prostatic epithelial PNT1A cells.

Fibroblast growth factor 7 (FGF7/KGF) is synthesized exclusively by fibroblasts in normal tissues; it acts as a potent mitogen on epithelial cells, through interaction with the FGF7-specific receptor FGFR2/IIIb. To examine the importance of this growth factor both to prostate physiology and to prostate-cancer progression, we have tested the exogenous effect of FGF7. Thus, by mimicking the paracrine pathway (on proliferation, growth in soft agar and invasion) on the human prostatic epithelial cell line PNT1A positively checked for FGFR2/IIIb expression, FGF7 significantly enhanced cell proliferation at an optimal concentration of 7.5 x 10(-11) M, but no significant invasion or growth in soft agar were observed. To confirm FGF7 properties on human prostatic epithelial cells, we constitutively expressed FGF7 by transfecting PNT1A cells with FGF7-cDNA. The FGF7-transfected clones, PNT1A/ FGF7-T5 and PNT1A/FGF7-T6, were stable and expressed FGF7. Analysis of the FGF7-autocrine loop on the non-tumorigenic epithelial cells PNT1A showed acquired invasive potential in in vitro extracellular-matrix migration assays, specifically inhibited by an FGF7-neutralizing antibody, and over-expressed factors implicated in the migration process: the metalloproteinase MMP-1 and the plasminogen activator uPA. Taken together, these results demonstrate a role for FGF7 in triggering invasion of human prostatic epithelial cells. Furthermore, these FGF7-transfected clones exhibited functional and physiological differences from the original PNT1A cell line: anchorage-independent growth, growth in serum-free media and increased proliferation. These data confirm the oncogenic function of FGF7 in prostate progression potentially acting through paracrine and/or autocrine regulatory pathways.

Regulation of cdc2 gene expression by the upstream stimulatory factors (USFs).

cdc2 gene expression is under the control of multiple factors. Although E2F/DP proteins have been reported to play a central role, they cannot account for all aspects of the fine modulation of cdc2 gene expression during cell cycle and embryonic development. To characterize the transcription factors that control cdc2 gene expression during nerve cell differentiation in avians, we have previously cloned the quail cdc2 gene promoter region. We had identified an octamer (CAGGTGGC) containing an E-box, which has important activity in regulating cdc2 transcription. Using in vivo genomic footprinting experiments, we show here that this motif, currently named IG, is the target of binding proteins at different stages of neuroretina development, confirming its importance as a regulatory response element for cdc2 gene expression. A subset of Helix-Loop-Helix family of transcription factors, known as Upstream Stimulatory Factors (USFs) specifically bind to this sequence as dimers. Moreover, our results indicate that USFs transactivate the promoter of cdc2 via the IG motif. These data may help to better understand the mechanisms that control cell division in differentiating nerve cells.