Outcomes of rescue procedures in the management of locally recurrent ampullary tumors: A Pancreas 2000/EPC study

BACKGROUND

Ampullary lesions are rare and can be locally treated either with endoscopic papillectomy or transduodenal surgical ampullectomy. Management of local recurrence after a first-line treatment has been poorly studied.

METHODS

Patients with a local recurrence of an ampullary lesion initially treated with endoscopic papillectomy or transduodenal surgical ampullectomy were retrospectively included from a multi-institutional database (58 centers) between 2005 and 2018.

RESULTS

A total of 103 patients were included, 21 (20.4%) treated with redo endoscopic papillectomy, 14 (13.6%) with transduodenal surgical ampullectomy, and 68 (66%) with pancreaticoduodenectomy. Redo endoscopic papillectomy had low morbidity with 4.8% (n = 1) severe to fatal complications and a R0 rate of 81% (n = 17). Transduodenal surgical ampullectomy and pancreaticoduodenectomy after a first procedure had a higher morbidity with Clavien III and more complications, respectively, 28.6% (n = 4) and 25% (n = 17); R0 resection rates were 85.7% (n = 12) and 92.6% (n = 63), both without statistically significant difference compared to endoscopic papillectomy (P = .1 and 0.2). Pancreaticoduodenectomy had 4.4% (n = 2) mortality. No deaths were registered after transduodenal surgical ampullectomy or endoscopic papillectomy. Recurrences treated with pancreaticoduodenectomy were more likely to be adenocarcinomas (79.4%, n = 54 vs 21.4%, n = 3 for transduodenal surgical ampullectomy and 4.8%, n = 1 for endoscopic papillectomy, P < .0001). Three-year overall survival and disease-free survival were comparable.

CONCLUSION

Endoscopy is appropriate for noninvasive recurrences, with resection rate and survival outcomes comparable to surgery. Surgery applies more to invasive recurrences, with transduodenal surgical ampullectomy rather for carcinoma in situ and early cancers and pancreaticoduodenectomy for more advanced tumors.

Tomography of irregular rough particles using the error-reduction algorithm with multi-views interferometric particle imaging

This work reports the 3D reconstruction of a particle from a set of three simulated interferometric images of this particle (from three perpendicular angles of view). The reconstruction of each view from its corresponding interferometric pattern uses the error-reduction (ER) algorithm. The 3D reconstruction enables an estimation of the volume of the particle. The method is tested on a dendrite-like particle. An experimental demonstration of the technique is done using a digital micromirror device (DMD) that generates the interferometric images of "programmable" rough particles.

Management of colorectal peritoneal metastases: Expert opinion

When peritoneal metastases are diagnosed (strong agreement of experts): (i) seek advice from a multidisciplinary coordination meeting (MCM) with large experience in peritoneal disease (e.g. BIG RENAPE network); (ii) transfer (or not) the patient to a referral center with experience in hyperthermic intraperitoneal chemotherapy (HIPEC), according to the advice of the MCM. With regard to systemic chemotherapy (strong agreement of experts): (i) it should be performed both before and after surgery, (ii) for no longer than 6 months; (iii) without postoperative anti-angiogenetic drugs. With regard to cytoreductive surgery (strong agreement of experts): (i) Radical surgery requires a xiphopubic midline incision; (ii) no cytoreductive surgery via laparoscopy. With regard to HIPEC: HIPEC can be proposed for trials outside an HIPEC referral center (weak agreement between experts): (i) if surgery is radical; (ii) if the expected morbidity is "reasonable"; (iii) if the indication for HIPEC was suggested by a MCM, and; (iv) mitomycin is preferred to oxaliplatin (which cannot be recommended) for this indication.

3D-reconstructions for the estimation of ice particle's volume using a two-views interferometric out-of-focus imaging set-up

The characterization of ice crystals has important applications in airborne research and civil aviation. Interferometric out-of-focus imaging is a promising technique. We investigate in this study the impact of the 3D shape reconstruction of the particles from a pair of interferometric images on the estimation of the ice particle's volume. An interferometric image gives indeed the 2D autocorrelation of the particle's shape. As different shapes can exhibit a similar 2D autocorrelation, particles of different shapes can have similar interferometric images. In this study, the volume of ice particles is estimated from a pair of interferometric images (with two perpendicular angles of view). The relative error in the particle's volume estimation is shown to be around ΔV V≈30% depending on the choice of the initial 3D particle's shape. It appears that the choice of the shape of the particle for both angles of view has a lower impact on the estimation of the particle's volume than the other sources of errors due to image acquisitions themselves.

Interferometric particle imaging of ice particles using a multi-view optical system

Interferometric particle imaging enables particle size estimation in a wide range [from 10 μm to a few millimeters] depending on the optical system design. With a multi-view optical system, it is possible to extract more information about the 3D morphology of the particle. In this study, multi-view interferometric out-of-focus imaging of ice particles is performed in a backward-scattering configuration. It is used to estimate ice particle volume and thus to reduce uncertainty concerning particle size estimation. It is further used to better analyze the presence of nearby particles whose images overlap.

Beat note stabilization in dual-polarization DFB fiber lasers by an optical phase-locked loop

A fully fibered microwave-optical source at 1.5 µm is studied experimentally. It is shown that the beat note between two orthogonally polarized modes of a distributed-feedback fiber laser can be efficiently stabilized using an optical phase-locked loop. The pump-power-induced birefringence serves as the actuator. Beat notes at 1 GHz and 10 GHz are successfully stabilized to a reference synthesizer, passing from the 3 kHz free-running linewidth to a stabilized sub-Hz linewidth, with a phase noise as low as -75 dBc/Hz at 100 Hz offset from the carrier. Such dual-frequency stabilized lasers could provide compact integrated components for RF and microwave photonics applications.

Growth kinetics and morphology of snowflakes in supersaturated atmosphere using a three-dimensional phase-field model

Simulating ice crystal growth is a major issue for meteorology and aircraft safety. Yet, very few models currently succeed in reproducing correctly the diversity of snow crystal forms, and link the model parameters to thermodynamic quantities. Here, we demonstrate that the new three-dimensional phase-field model developed in Demange et al. [npj Comput. Mater. 3, 1 (2017)2057-396010.1038/s41524-017-0015-1] is capable of reproducing properly the morphology and growth kinetics of snowflakes in supersaturated atmosphere. Aside from that, we show that the growth dynamics of snow crystals satisfies the selection theory, consistently with previous experimental observations. Finally, we link the parameters of the phase-field model to atmospheric parameters.

Instrumentation for ice crystal characterization in laboratory using interferometric out-of-focus imaging

Airborne characterization of ice crystals has important applications. The extreme difficulty of realizing in situ tests requires the development of a complete instrumentation in the laboratory. Such an installation should enable design, development, test, and calibration of instruments in conditions as close as possible to real ones. We present a set of numerical and experimental tools that have been developed to realize ice crystal sensors based on interferometric particle imaging. The set of tools covers the development of complementary simulators for crystal growth and interferometric particle imaging predictions, experimental generation of "programmable" ice crystals, and instrumentation of a freezing column where different techniques as in-focus imaging, out-of-focus imaging, and digital in-line holography can be combined simultaneously for test and calibration.

Digital micromirror device as programmable rough particle in interferometric particle imaging

The 2D autocorrelation of the projection of an irregular rough particle can be estimated using the analysis of its interferometric out-of-focus image. We report the development of an experimental setup that creates speckle-like patterns generated by "programmable" rough particles of desired-shape. It should become an important tool for the development of new setups, configurations, and algorithms in interferometric particle imaging.

3D-shape recognition and size measurement of irregular rough particles using multi-views interferometric out-of-focus imaging

We realize simplified-tomography experiments on irregular rough particles using interferometric out-of-focus imaging. Using two angles of view, we determine the global 3D-shape, the dimensions, and the 3D-orientation of irregular rough particles whose morphologies belong to families such as sticks, plates, and crosses.

Interferometric out-of-focus imaging of ice particles with overlapping images

It is shown that the size and relative positions of two irregular rough particles can be analyzed using interferometric out-of-focus imaging despite the overlapping of their out-of-focus images. Simulations are confirmed by experiments done with ice particles generated in a freezing column.

Dual-wavelength digital holography for 3D particle image velocimetry: experimental validation

A multi-exposure digital in-line hologram of a particle field is recorded by two successive pulses of different wavelengths. During the reconstruction step, each recording can be independently analyzed by selecting a given wavelength. This procedure enables avoiding the superimposition of particle images that may be close to each other.

Simultaneous 3D location and size measurement of bubbles and sand particles in a flow using interferometric particle imaging

We present a system to characterize a triphasic flow in a 3D volume (air bubbles and solid irregular particles in water) using only one CCD sensor. A cylindrical interferometric out-of-focus imaging setup is used to determine simultaneously the 3D position and the size of bubbles and irregular sand particles in a flow. The 3D position of the particles is deduced from the ellipticity of their out-of-focus image. The size of bubbles is deduced from analysis of interference fringes. The characteristics of irregular sand particles are obtained from analysis of their speckle-like pattern. Experiments are confirmed by simulations.

Measuring the universal synchronization properties of driven oscillators across a Hopf instability

When a driven oscillator loses phase-locking to a master oscillator via a Hopf bifurcation, it enters a bounded-phase regime in which its average frequency is still equal to the master frequency, but its phase displays temporal oscillations. Here we characterize these two synchronization regimes in a laser experiment, by measuring the spectrum of the phase fluctuations across the bifurcation. We find experimentally, and confirm numerically, that the low frequency phase noise of the driven oscillator is strongly suppressed in both regimes in the same way. Thus the long-term phase stability of the master oscillator is transferred to the driven one, even in the absence of phase-locking. The numerical study of a generic, minimal model suggests that such behavior is universal for any periodically driven oscillator near a Hopf bifurcation point.

Long time exposure digital in-line holography for 3-D particle trajectography

One advantage of digital in-line holography is the ability for a user to know the 3-D location of a moving particle recorded at a given time. When the time exposure is much larger than the time required for grabbing the particle image at a given location, the diffraction pattern is spread along the trajectory of this particle. This can be seen as a convolution between the diffraction pattern and a blurring function resulting from the motion of the particle during the camera exposure. This article shows that the reconstruction of holograms recorded under such conditions exhibit traces that could be processed for extracting 3D trajectories.

Lidar-radar velocimetry using a pulse-to-pulse coherent rf-modulated Q-switched laser

An rf-modulated pulse train from a passively Q-switched Nd:YAG laser has been generated using an extra-cavity acousto-optic modulator. The rf modulation reproduces the spectral quality of the local oscillator. It leads to a high pulse-to-pulse phase coherence, i.e., phase memory, over thousands of pulses. The potentialities of this transmitter for lidar-radar are demonstrated by performing Doppler velocimetry on indoor moving targets. The experimental results are in good agreement with a model based on elementary signal processing theory. In particular, we show experimentally and theoretically that lidar-radar is a promising technique that allows discrimination between translation and rotation movements. Being independent of the laser internal dynamics, this scheme can be applied to any Q-switched laser.

Reverse saturable Absorption in Organically Doped Xerogels

Pd and Zn - tetraphenyltetrabenzoporphyrins (PdTPTBP and ZnTPTBP), hexacyanin 3 (HITCI), and substituted phthalocyanines were incorporated in solid-state matrices (xerogels) using a sol-gel process. Nonlinear reverse saturable absorption was observed with those materials when they were illuminated with nanosecond laser pulses at 532 nm, or other wavelengths in the visible spectrum (between 450 nm and 630 nm). PdTPTBP doped xerogels exhibit a nonlinear activation threshold of about 10 mJ/cm , which is much lower than the value of 80 mJ/cm2 obtained under similar conditions with classical Al phthalocyanine chloride, or HITCI molecules. Solid state “red active” reverse saturable absorbers can be obtained with substituted phthalocyanines doped xerogels. The different experimental results are discussed using classical 4- energy level diagrams.

Dual-polarization mode-locked Nd:YAG laser

A mode-locked solid-state laser containing a birefringent element is shown to emit synchronously two frequency combs associated to the two polarization eigenstates of the cavity. An analytical model predicts the polarization evolution of the pulse train, which is determined by the adjustable intracavity birefringence. Experiments realized with a Nd:YAG laser passively mode locked by a semiconductor saturable absorber mirror are in perfect agreement with the model. Locking between the two combs arises for particular values of their frequency difference, e.g., half the repetition rate, and the pulse train polarization sequence is then governed by the relative overall phase offset of the two combs.

Non-linear optoelectronic phase-locked loop for stabilization of opto-millimeter waves: towards a narrow linewidth tunable THz source

We propose an optoelectronic phase-locked loop concept which enables to stabilize optical beat notes at high frequencies in the mm-wave domain. It relies on the use of a nonlinear-response Mach-Zehnder modulator. This concept is demonstrated at 100 GHz using a two-axis dual-frequency laser turned into a voltage controlled oscillator by means of an intracavity electrooptic crystal. A relative frequency stability better than 10⁻¹¹ is reported. This approach of optoelectronic down conversion opens the way to the realization of continuously tunable ultra-narrow linewidth THz radiation.

Resonance assisted synchronization of coupled oscillators: frequency locking without phase locking

Frequency locking without phase locking of two coupled nonlinear oscillators is experimentally demonstrated. This synchronization regime is found for two coupled laser modes, beyond the phase-locking range fixed by Adler's equation, because of a resonance mechanism. Specifically, we show that the amplitudes of the two modes exhibit strong fluctuations that produce average frequency synchronization, even if the instantaneous phases are unlocked. The experimental results are in good agreement with a theoretical model.

Beat note stabilization of a 10-60 GHz dual-polarization microlaser through optical down conversion

Down-conversion of a high-frequency beat note to an intermediate frequency is realized by a Mach-Zehnder intensity modulator. Optically-carried microwave signals in the 10-60 GHz range are synthesized by using a two-frequency solid-state microchip laser as a voltage-controlled oscillator inside a digital phase-locked loop. We report an in-loop relative frequency stability better than 2.5×10⁻¹¹. The principle is applicable to beat notes in the millimeter-wave range.

Structural, Optical and Electrical Properties of μc-Si:H Very Thin Films Deposited by the VHF-GD Technique. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-336-511]

In this paper we present new results for very thin <p> μc-Si:H films (< 350 Å) deposited at low temperature (170 C) by the Very High Frequency - Glow Discharge technique (VHF-GD) at 70 MHz. First, the effect of boron doping on the growth and electrical properties of μc-Si:H very thin films is investigated, leading to an optimised value of about 0.6 % (B2H6/SiH4). Structural properties of an optimised thickness series ranging from 100 to 350 Å are studied using TEM, Raman, grazing angle X-ray diffraction/reflection and spectroscopie ellipsometry. Further, a columnar structure growth model for these very thin <p>-type μc-Si:H films will be proposed.

Suppression of the Moiré effect in sub-picosecond digital in-line holography

Digital in-line holography is widely used in flow studies where the 3D position, size and velocity of particles or fibers have to be known at a given time. When holograms are recorded by using a sub-picosecond laser the enlargement of the spectral distribution acts as a spatial low-pass filter over the intensity distribution of the diffraction pattern. This is not a disadvantage as regards to the spatial sampling. Indeed, the Moiré effect, due to the sub-sampling of the fringe pattern is naturally reduced. Experimental results are provided.

Generation of parabolic bound pulses from a Yb-fiber laser

We report the observation of self-similar propagation of bound-state pulses in an ytterbium-doped double-clad fiber laser. A bound state of two positively chirped parabolic pulses with 5.4 ps duration separated by 14.9 ps is obtained, with 1.7 nJ of energy per pulse. These pulses are extra-cavity compressed to 100 fs. For higher pumping power and a different setting of the intra-cavity polarization controllers, the laser generates a bound state of three chirped parabolic pulses with different time separations and more than 1.5 nJ energy per pulse. Perturbation of this bound state by decreasing pump power results in the generation of a single pulse and a two-pulse bound state both structures traveling at the same velocity along the cavity. A possible explanation of the zero relative speed by a particular phase relation of the bound states is discussed.

Application of the fractional Fourier transformation to digital holography recorded by an elliptical, astigmatic Gaussian beam

The authors have studied the diffraction pattern produced by a particle field illuminated by an elliptic and astigmatic Gaussian beam. They demonstrate that the bidimensional fractional Fourier transformation is a mathematically suitable tool to analyse the diffraction pattern generated not only by a collimated plane wave [J. Opt. Soc. Am A 19, 1537 (2002)], but also by an elliptic and astigmatic Gaussian beam when two different fractional orders are considered. Simulations and experimental results are presented.

Functional results after the Orr-Loygue transabdominal rectopexy for complete rectal prolapse

PURPOSE

The aim of this study was to assess functional results after Orr-Loygue transabdominal rectopexy for complete rectal prolapse.

METHODS

Thirty-one consecutive patients operated on for complete rectal prolapse between 1995 and 1998 were evaluated preoperatively and postoperatively with regard to anal incontinence, constipation, evacuation difficulties, and overall satisfaction with a standardized questionnaire. Anal continence assessment was based on a clinical scoring system.

RESULTS

After a mean follow-up of 28 +/- 13 (range, 12-57) months, no prolapse recurred. Preoperative and postoperative rates of incontinence were 81 percent (25/31) and 55 percent (17/31), respectively (P < 0.03). Continence improved in 24 (96 percent) of the 25 patients who were incontinent before surgery. The mean incontinence score decreased from 11.7 +/- 7.8 preoperatively to 3.2 +/- 4.2 postoperatively (P < 0.001). The self-reported constipation rate was 61 percent (19/31) before surgery and 71 percent (22/31) after surgery (P = nonsignificant). Constipation appeared or worsened in 16 patients (52 percent), whereas it disappeared or improved in 8 (26 percent; P = nonsignificant). Evacuation difficulties increased significantly after surgery from 23 percent (7/31) to 61 percent (19/31; P < 0.003). Ninety-seven percent of patients reported good or very good satisfaction.

CONCLUSIONS

Transabdominal Orr-Loygue rectopexy resulted in improved continence and a high satisfaction level. Despite a significant postoperative increase in evacuation difficulties, only a 10 percent (nonsignificant) increase in the self-reported constipation rate was observed.

Two-frequency Er-Yb:glass microchip laser passively Q switched by a Co:ASL saturable absorber

Passive Q switching of a two-frequency Er3+-Yb3+:glass laser at 1.55 microm with a new Co2+:La(x)Sr(1 - x)Mg(x - y)Co(y)Al(12 - x)O19 crystal as a saturable absorber is demonstrated. We show that, with an extended cavity setup, the beat frequency between the orthogonally polarized laser eigenstates is continuously tunable by adjustment of the retardance of an intracavity birefringence. A similarly built microchip laser emits two-frequency pulses of 6-ns duration with a beat frequency of as much as 19 GHz. Moreover, two-frequency pulses at 777 nm are obtained by second-harmonic generation in a periodically poled lithium niobate crystal. Such pulses can be useful for applications such as Doppler lidar radar.

Lever-assisted two-noise stochastic resonance

A critical interplay of two correlated noises in a nonlinear symmetrical two-well potential system is experimentally demonstrated. One state can become completely noise free, leading to an infinite Kramers time. If an independent lever breaks the potential symmetry, stochastic resonance is recovered. In this new regime, we obtain a plateau, i.e., a high signal-to-noise ratio even for vanishing forcing signals.

Stochastic resonances in an optical two-order parameter vectorial system

We show experimentally that optical two-dimensional systems such as vectorial lasers can exhibit novel stochastic resonances. All optical noise and modulation of this system allows the isolation of so-called inhibitional and rotational stochastic resonances. In particular, incoherent rotational tunneling is shown to be sensitive enough to be also induced by Faraday noise and by quantum noise, i.e., external spontaneous emission.

Characterization of chirped pulses with the fractional-order Fourier transformation

We show that the fractional-order Fourier transformation (FRT) is a suitable method to describe chirped pulses submitted to group-velocity dispersion in a linear dispersive medium. Amplitudes exhibiting different chirp coefficients are easily separated with the FRT, although they are temporally superposed.

?erenkov-based radiation from superluminal excitation in microdroplets by ultrashort pulses

We demonstrate from a generalized Lorenz-Mie theory that ultrashort pulses can induce superluminal excitation in microdroplets. A ?erenkov-like effect can thus be expected for sufficiently intense ultrashort pulses.

Aspergillus niger I-1472 and Pycnoporus cinnabarinus MUCL39533, selected for the biotransformation of ferulic acid to vanillin, are also able to produce cell wall polysaccharide-degrading enzymes and feruloyl esterases

The filamentous fungal strains Aspergillus niger I-1472 and Pycnoporus cinnabarinus MUCL39533, previously selected for the bioconversion of ferulic acid to vanillic acid and vanillin respectively, were grown on sugar beet pulp. A large spectrum of polysaccharide-degrading enzymes was produced by A. niger and very few levels of feruloyl esterases were found. In contrast, P. cinnabarinus culture filtrate contained low amount of polysaccharide-degrading enzymes and no feruloyl esterases. In order to enhance feruloyl esterases in A. niger cultures, feruloylated oligosaccharide-rich fractions were prepared from sugar beet pulp or cereal bran and used as carbon sources. Number of polysaccharide-degrading enzymes were induced. Feruloyl esterases were much higher in maize bran-based medium than in sugar beet pulp-based medium, demonstrating the ability of carbon sources originating from maize to induce the synthesis of feruloyl esterases. Thus, A. niger I-1472 could be interesting to release ferulic acid from sugar beet pulp or maize bran.

Primary Hyperparathyroidism and Lymphoproliferative Diseases: Three Case Reports

Pathophysiologic mechanisms of malignancy-associated hypercalcemia are varied. The association of neoplasia and primary hyperparathyroidism (PHP) has been illustrated by clinical cases and by epidemiologic studies which have pointed to an increased risk of different malignancies during PHP. The authors report two cases of monoclonal gammapathy and one case of chronic lymphocytic leukemia (CLL) associated with PHP. A 58-year-old man presented with hypercalcemia due to PHP after remission for multiple plasmacytoma was obtained. A 70-year-old man was hospitalized for malaise, studies showed major hypercalcemia and benign monoclonal gammapathy. In the two cases, resolution of hypercalcemia was obtained by parathyroidectomy. The third patient was a 84-year-old woman with CLL who continued to deteriorate despite response to therapy, further studies confirmed hyperparathyroidism Physiopathogenic mechanisms of this association are discussed. The PHP-malignancy association should be considered ifthe symptoms or outcome of anyone of the two diseases are atypic.

Parovirus B19 infection in an HIV-infected patient with febrile pancytopenia and acute hepatitis

The case of a 34-year-old male patient with HIV infection referred for severe febrile pancytopenia is reported. Clinical and laboratory evaluations revealed acute hepatitis B infection and concomitant parvovirus B19 infection. The patient died just before treatment with immune globulin was to be administered. Parvovirus B19 has been found to cause a wide variety of hematologic disorders such as neutropenia, thrombocytopenia, pancytopenia, and hemophagocytic syndrome. The role of parvovirus B19 in the pathogenesis of bone marrow or liver involvement is briefly discussed.

Hemophagocytic Syndrome Induced by HIV

Hemophagocytic syndrome is an unusual illness due to the proliferation of activated macrophages phagocyting the hematopoietic cells. This syndrome has been reported in association with infectious agents, lymphoproliferative diseases, immunosuppressive conditions or auto-immune illnesses. Cytokines secreted by activated or neoplastic lympho-cytes activate the macrophages. Autocrine and paracrine mechanisms take over and could explain resistance to therapy. Some viruses, including EBV, could upregulate cytokine genes. This report describes an adult with HIV-infection presenting with severe hemophagocytic syndrome in whom an extensive evaluation did not reveal opportunistic disease and suggests that the cause was the HIV. The outcome was fatal and highlights the poor prognosis of hemophagocytic syndrome in this context.

X-ray diffraction from perfect silicon crystals distorted by surface acoustic waves

High-resolution X-ray diffraction measurements were carried out on ZnO/Si devices under surface acoustic wave excitation and revealed some very clear satellite diffraction peaks that are obtained from the sinusoidal modulation of the near-surface region. This experiment shows that the propagation of a Rayleigh surface acoustic wave in a perfect crystal acts as a dynamical diffraction grating. The variation of the acoustic velocity has been followed across the crystal surface from the acoustic source region (beneath the ZnO film) to the far field region (not covered by the ZnO film).