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1.
Rev Med Liege ; 75(12): 767-769, 2020 Dec.
Article in French | MEDLINE | ID: mdl-33331698

ABSTRACT

A young patient consulted in our physical and rehabilitation medicine department following the onset of pain on the scapula area and at the base of his right upper limb after carrying a heavy load. After a couple of weeks, the patient also developed cervical pain. Fortuitously, the cervical scanner displayed a right C6 spondylolysis. Further evaluation by bone scan confirmed that this lesion was not recent and so probably not the cause of the symptoms. Cervical isthmic spondylolysis is a rare condition, much more common at the lumbar level and often ignored at the cervical one. The etiology, pahophysiology, imaging and treatment options for this cervical pathology are discussed in this article.


Un jeune patient a consulté en médecine physique pour des douleurs aux niveaux de l'omoplate et de la racine du membre supérieur droit apparues suite au port d'une charge lourde. Après quelques semaines, le patient se plaignait également de cervicalgies. Un scanner du rachis cervical a objectivé fortuitement une spondylolyse C6 droite. Un bilan complémentaire par scintigraphie osseuse a révélé que la lésion était ancienne et qu'elle n'était probablement pas la cause de la symptomatologie. La lyse isthmique cervicale est une pathologie peu répandue. Très connue à l'étage lombaire, la spondylolyse est rare et souvent ignorée au niveau cervical. L'étiologie, la physiopathologie, l'imagerie et la prise en charge de cette pathologie cervicale sont discutées dans cet article.


Subject(s)
Spondylolysis , Tomography, X-Ray Computed , Humans , Lumbar Vertebrae , Neck , Spondylolysis/diagnostic imaging
2.
Opt Lett ; 43(15): 3574-3577, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-30067627

ABSTRACT

We develop a pulsed hard x-ray Kα source at 17.4 keV produced by the interaction of a multi-terawatt peak power infrared femtosecond laser pulse with a thick molybdenum (Mo) target at a 100 Hz repetition rate. We measure the highest Mo Kα photon production reported to date corresponding to a Kα photon flux of 1×1011 ph/(sr·s) and an estimated peak brightness of ∼2.5×1017 ph/(s·mm2·mrad2(0.1% bandwidth)) at ∼5×1018 W/cm2 driving laser intensity.

3.
Phys Rev Lett ; 116(5): 053002, 2016 Feb 05.
Article in English | MEDLINE | ID: mdl-26894708

ABSTRACT

Probing electronic wave functions of polyatomic molecules is one of the major challenges in high-harmonic spectroscopy. The extremely nonlinear nature of the laser-molecule interaction couples the multiple degrees of freedom of the probed system. We combine two-dimensional control of the electron trajectories and vibrational control of the molecules to disentangle the two main steps in high-harmonic generation-ionization and recombination. We introduce a new measurement scheme, frequency-resolved optomolecular gating, which resolves the temporal amplitude and phase of the harmonic emission from excited molecules. Focusing on the study of vibrational motion in N_{2}O_{4}, we show that such advanced schemes provide a unique insight into the structural and dynamical properties of the underlying mechanism.

4.
Br J Cancer ; 111(7): 1454-62, 2014 Sep 23.
Article in English | MEDLINE | ID: mdl-25101568

ABSTRACT

BACKGROUND: Although there are solid findings regarding the detrimental effect of alcohol consumption, the existing evidence on the effect of other dietary factors on breast cancer (BC) risk is inconclusive. This study aimed to evaluate the association between dietary patterns and risk of BC in Spanish women, stratifying by menopausal status and tumour subtype, and to compare the results with those of Alternate Healthy Index (AHEI) and Alternate Mediterranean Diet Score (aMED). METHODS: We recruited 1017 incident BC cases and 1017 matched healthy controls of similar age (±5 years) without a history of BC. The association between 'a priori' and 'a posteriori' developed dietary patterns and BC in general and according to menopausal status and intrinsic tumour subtypes (ER+/PR+ and HER2-; HER2+; and ER-/PR- and HER2-) was evaluated using logistic and multinomial regression models. RESULTS: Adherence to the Western dietary pattern was related to higher risk of BC (OR for the top vs the bottom quartile 1.46 (95% CI 1.06-2.01)), especially in premenopausal women (OR=1.75; 95% CI 1.14-2.67). In contrast, the Mediterranean pattern was related to a lower risk (OR for the top quartile vs the bottom quartile 0.56 (95% CI 0.40-0.79)). Although the deleterious effect of the Western pattern was similarly observed in all tumour subtypes, the protective effect of our Mediterranean pattern was stronger for triple-negative tumours (OR=0.32; 95% CI 0.15-0.66 and Pheterogeneity=0.04). No association was found between adherence to the Prudent pattern and BC risk. The associations between 'a priori' indices and BC risk were less marked (OR for the top vs the bottom quartile of AHEI=0.69; 95% CI 0.51-0.94 and aMED=0.74; 95% CI 0.46-1.18)). CONCLUSIONS: Our results confirm the harmful effect of a Western diet on BC risk, and add new evidence on the benefits of a diet rich in fruits, vegetables, legumes, oily fish and vegetable oils for preventing all BC subtypes, and particularly triple-negative tumours.


Subject(s)
Diet, Mediterranean , Triple Negative Breast Neoplasms/etiology , Case-Control Studies , Female , Humans , Incidence , Risk , Spain , Triple Negative Breast Neoplasms/epidemiology
5.
J Bodyw Mov Ther ; 39: 525-530, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38876679

ABSTRACT

The Askling's H-test is considered a useful return to play criterion after a hamstring muscle injury (HMI). However, it assesses only the active and passive flexibility of posterior thigh muscles. This may lead the practitioner to underestimate a compensation or abnormal movement pattern. The aim of this study was to analyze these kinematic aspects and their reliability, and evaluate the hamstring (HM) and gluteus maximus (GM) muscles' activities. Twelve healthy male volunteers were tested during two session of three trials for passive and active tests. Dynamic flexibility (97.2 ± 6.0°) was significantly greater than the passive one (70.5 ± 14.7°) (p < 0.001), and good intra-individual reproductibility for most kinematic characteristics was observed. Biceps Femoris long head, semitendinosus and GM mean activities (20.1 ± 11.2%; 14.3 ± 7.3% and 25.2 ± 22.1%, respectively) were found to be low to moderate, indicating that only a moderate level of activity occurred during the active H-test, in comparison to other movements such as sprinting itself. In addition, the activity of the posterior thigh muscles during the active H-test appeared to be variable among the volunteers. These findings suggest that the H-test should be interpreted on an individual basis rather than relying on general characteristics, and be considered as an intermediate tool before more strenuous activities such as returning to sprint. With this comprehensive approach, clinicians can gain a more accurate understanding of their patients' progress and make more informed decisions about their readiness to return to play.


Subject(s)
Electromyography , Hamstring Muscles , Thigh , Humans , Male , Electromyography/methods , Biomechanical Phenomena/physiology , Hamstring Muscles/physiology , Adult , Thigh/physiology , Young Adult , Range of Motion, Articular/physiology , Muscle, Skeletal/physiology , Reproducibility of Results
6.
Phys Rev Lett ; 110(8): 083902, 2013 Feb 22.
Article in English | MEDLINE | ID: mdl-23473148

ABSTRACT

High order harmonic generation from clusters is a controversial topic: conflicting theories exist, with different explanations for similar experimental observations. From an experimental point of view, separating the contributions from monomers and clusters is challenging. By performing a spectrally and spatially resolved study in a controlled mixture of clusters and monomers, we are able to isolate a region of the spectrum where the emission purely originates from clusters. Surprisingly, the emission from clusters is depolarized, which is the signature of statistical inhomogeneous emission from a low-density source. The harmonic response to laser ellipticity shows that this generation is produced by a new recollisional mechanism, which opens the way to future theoretical studies.

7.
Neurologia ; 28(2): 103-18, 2013 Mar.
Article in English, Spanish | MEDLINE | ID: mdl-21163212

ABSTRACT

INTRODUCTION: In the current population, strokes are one of the most important causes of morbidity and mortality, to which new risk factors are increasingly being attributed. Of late, there is increased interest in the relationship between sleep disorders and strokes as regards risk and prognosis. DEVELOPMENT: This article presents the changes in sleep architecture and brain activity in stroke patients, as well as the interaction between stroke and sleep disorders, including those which may also influence the outcome and recovery from strokes. The different treatments discussed in the literature are also reviewed, as correct treatment of such sleep disorders may not only improve quality of life and reduce after-effects, but can also increase life expectancy. CONCLUSIONS: Sleep disorders are becoming increasingly associated with stroke. In addition to being a risk factor, they can also interfere in the outcome and recovery of stroke patients. This article aims to present an exhaustive and current review on strokes and their relationship with sleep alterations and sleep disorders.


Subject(s)
Sleep Wake Disorders/complications , Sleep Wake Disorders/physiopathology , Sleep/physiology , Stroke/etiology , Stroke/physiopathology , Brain/physiopathology , Circadian Rhythm/physiology , Disorders of Excessive Somnolence/etiology , Electroencephalography , Humans , Nocturnal Myoclonus Syndrome/etiology , Parasomnias/etiology , Prognosis , Risk Assessment , Sleep Apnea Syndromes/complications , Sleep Apnea Syndromes/physiopathology , Sleep Initiation and Maintenance Disorders/etiology , Sleep Stages
8.
Reanimation ; 22(1): 3-13, 2013.
Article in French | MEDLINE | ID: mdl-32288730

ABSTRACT

Usually, intensivists do not focus on atypical bacteria and viruses in severe community-acquired pneumonia (CAP). Only Legionella pneumophila and influenza virus, following the recent H1N1 influenza pandemic, are routinely suggested as responsible agents. However, CAP due to atypical bacteria may represent up to 44% of all CAP. Viral CAP is considered less severe than the usual bacterial ones, although 25% of them warrant hospitalization and 15% result in severe sepsis. Even though L. pneumophila is the most frequently atypical pathogen involved in severe cases, Mycoplasma pneumoniae may be responsible for multiorgan failure. To date, tools including detection of Legionella antigen in urine and Mycoplasma using polymerase chain reaction (PCR) allow rapid and accurate diagnosis. The treatment is based on macrolides and fluoroquinolones that can be associated in severe Legionnaire diseases. The presence of virus in CAP, either alone or in association with bacteria, has been demonstrated using molecular biology tests. These techniques also allowed the identification of several new viruses in CAP. However, the exact role of these detected viruses in CAP as well as the efficiency of antiviral therapy still represent major unsolved concerns.

9.
Prog Urol ; 23(3): 195-202, 2013 Mar.
Article in French | MEDLINE | ID: mdl-23446284

ABSTRACT

PURPOSE: Prospective evaluation of bladder tumor targeting by Hexvix(®) fluorescence. PATIENTS AND METHODS: From September 2008 to April 2012, 107 patients have been evaluated using Hexvix(®) technique (blue light) for typically papillary bladder tumor or suspected bladder tumor. Clinical and pathological data have been collected prospectively and patients have been classified using EORTC score. RESULTS: From the 107 patients, 67 have been identified with bladder cancer and 328 samples have shown positive fluorescence in blue light. Compared to white light, 13 additional tumors have been diagnosed by Hexvix(®) for 11 patients: Cis (n=6), LMP (n=3), pTa low grade (n=3), pT1 low grade (n=1) (P=0.003). The false positive rate for Hexvix(®) was 53.4% versus 52% for white light. Previous TCC history, multifocality and EORTC score for recurrence and progression have been associated with better bladder cancer targeting by Hexvix(®) (P=0.007; P=0.01; P=0.03; P=0.04). CONCLUSION: In our experience, Hexvix(®) targeting was associated with better diagnosis for bladder cancer with 9% (13/144) of new positive samples (P=0.003). In our study, false positive rate is a critical point (53.4%). Multifocality, previous TCC, and EORTC score for recurrence and progression might allow selecting patients to be targeted by Hexvix(®).


Subject(s)
Aminolevulinic Acid/analogs & derivatives , Cystoscopy/methods , Light , Photosensitizing Agents , Urinary Bladder Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Female , Fluorescence , France , Humans , Male , Middle Aged , Neoplasm Invasiveness , Neoplasm Staging , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity , Survival Analysis , Urinary Bladder Neoplasms/diagnosis , Urinary Bladder Neoplasms/mortality
10.
Br J Anaesth ; 109(3): 330-8, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22735299

ABSTRACT

BACKGROUND: We evaluated the ability of an infrared photoplethysmography arterial waveform (continuous non-invasive arterial pressure, CNAP) to estimate arterial pulse pressure variation (PPV). We compared the ability of non-invasive PPV to predict fluid responsiveness with invasive PPV, respiratory variation of pulse contour-derived stroke volume, and changes in cardiac index induced by passive leg raising (PLR) and end-expiratory occlusion (EEO) tests. METHODS: We measured the responses of cardiac index (PiCCO) to 500 ml of saline in 47 critically ill patients with haemodynamic failure. Before fluid administration, we recorded non-invasive and invasive PPVs, stroke volume variation, and changes in cardiac index induced by PLR and by 15 s EEO. Logistic regressions were performed to investigate the advantage of combining invasive PPV, stroke volume variation, PLR, and EEO when predicting fluid responsiveness. RESULTS: In eight patients, CNAP could not record arterial pressure. In the 39 remaining patients, fluid increased cardiac index by ≥15% in 17 'responders'. Considering the 195 pairs of measurements, the bias (sd) between invasive and non-invasive PPVs was -0.6 (2.3)%. The areas under the receiver operating characteristic (ROC) curves for predicting fluid responsiveness were 0.89 (95% confidence interval, 0.78-1.01) for non-invasive PPV compared with 0.89 (0.77-1.01), 0.84 (0.70-0.96), 0.95 (0.88-1.03), and 0.97 (0.91-1.03) for invasive pulse pressure, stroke volume variations, PLR, and EEO tests (no significant difference). Combining multiple tests did not significantly improve the area under the ROC curves. CONCLUSIONS: Non-invasive assessment of PPV seems valuable in predicting fluid responsiveness.


Subject(s)
Blood Pressure , Fluid Therapy , Adult , Aged , Aged, 80 and over , Critical Illness/therapy , Humans , Logistic Models , Middle Aged , Photoplethysmography , ROC Curve , Stroke Volume
11.
J Chem Phys ; 137(22): 224303, 2012 Dec 14.
Article in English | MEDLINE | ID: mdl-23248999

ABSTRACT

We study theoretically and experimentally the electronic relaxation of NO(2) molecules excited by absorption of one ∼400 nm pump photon. Semiclassical simulations based on trajectory surface hopping calculations are performed. They predict fast oscillations of the electronic character around the intersection of the ground and first excited diabatic states. An experiment based on high-order harmonic transient grating spectroscopy reveals dynamics occurring on the same time scale. A systematic study of the detected transient is conducted to investigate the possible influence of the pump intensity, pump wavelength, and rotational temperature of the molecules. The quantitative agreement between measured and predicted dynamics shows that, in NO(2), high harmonic transient grating spectroscopy encodes vibrational dynamics underlying the electronic relaxation.

12.
Sci Rep ; 11(1): 23318, 2021 Dec 02.
Article in English | MEDLINE | ID: mdl-34857801

ABSTRACT

The size of a hard Kα x-ray source ([Formula: see text] = 17.48 keV) produced by a high intensity femtosecond laser interacting with a solid molybdenum target is experimentally investigated for a wide range of laser intensity (I ~ 1017-2.8 × 1019 W/cm2) and for four values of the temporal contrast ratio (6.7 × 107 < CR < 3.3 × 1010). Results point out the size enlargement of the x-ray source with the increase of laser intensity and with the deterioration of temporal contrast. It amounts up to sixteen times the laser spot size at the highest laser intensity and for the lowest temporal contrast ratio. Using hydrodynamic simulations, we evaluate the density scale length of the pre-plasma L/λ just before the main pulse peak. This allows us to show that a direct correlation with the laser absorption mechanisms is not relevant to explain the large size broadening. By varying the thickness of the molybdenum target down to 4 µm, the impact of hot electron scattering inside the solid is also proved irrelevant to explain the evolution of both the x-ray source size and the Kα photon number. We deduce that the most probable mechanism yielding to the broadening of the source size is linked to the creation of surface electromagnetic fields which confine the hot electrons at the solid surface. This assumption is supported by dedicated experiments where the evolution of the size enlargement of the x-ray source is carefully studied as a function of the laser focal spot size for the highest contrast ratio.

13.
Clin Transl Oncol ; 23(5): 922-930, 2021 May.
Article in English | MEDLINE | ID: mdl-33405052

ABSTRACT

Soft-tissue sarcomas constitute an uncommon and heterogeneous group of tumors of mesenchymal origin. Diagnosis, treatment, and management should be performed by an expert multidisciplinary team. MRI/CT of the primary tumor and biopsy is mandatory before any treatment. Wide surgical resection with tumor-free tissue margin is the mainstay for localized disease. Radiotherapy is indicated in large, deep, high-grade tumors, or after marginal resection not suitable for re-excision. Perioperative chemotherapy should be discussed for high-risk sarcomas of the extremities and trunk-wall. In the case of oligometastatic disease, patients should be considered for local therapies. First-line treatment with anthracyclines (or in combination with ifosfamide) is the treatment of choice. Other drugs have shown activity in second-line therapy and in specific histological subtypes but options are limited and thus, a clinical trial should always be discussed.


Subject(s)
Sarcoma/diagnosis , Sarcoma/therapy , Soft Tissue Neoplasms/diagnosis , Soft Tissue Neoplasms/therapy , Anthracyclines/therapeutic use , Antineoplastic Agents/therapeutic use , Checklist , Chemotherapy, Adjuvant/methods , Dermatofibrosarcoma/therapy , Female , Fibromatosis, Aggressive/genetics , Fibromatosis, Aggressive/therapy , Humans , Magnetic Resonance Imaging , Male , Medical Oncology , Neoadjuvant Therapy/methods , Radiotherapy/methods , Retroperitoneal Neoplasms/therapy , Sarcoma/diagnostic imaging , Sarcoma/pathology , Societies, Medical , Soft Tissue Neoplasms/diagnostic imaging , Soft Tissue Neoplasms/pathology , Solitary Fibrous Tumors/drug therapy , Spain , Tomography, X-Ray Computed , Uterine Neoplasms/therapy
14.
Sci Rep ; 10(1): 6766, 2020 04 21.
Article in English | MEDLINE | ID: mdl-32317682

ABSTRACT

This study explores the ability of a hard Kα x-ray source (17.48 keV) produced by a 10 TW class laser system operated at high temporal contrast ratio and high repetition rate for phase contrast imaging. For demonstration, a parametric study based on a known object (PET films) shows clear evidence of feasibility of phase contrast imaging over a large range of laser intensity on target (from ~1017 W/cm2 to 7.0 × 1018 W/cm2). To highlight this result, a comparison of raw phase contrast and retrieved phase images of a biological object (a wasp) is done at different laser intensities below the relativistic intensity regime and up to 1.3 × 1019 W/cm2. This brings out attractive imaging strategies by selecting suitable laser intensity for optimizing either high spatial resolution and high quality of image or short acquisition time.

15.
J Intern Med ; 265(1): 58-66, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19093960

ABSTRACT

Mucosal surfaces of the body serve as the major portal of entry for human immunodeficiency virus (HIV). These tissues also house a majority of the body's lymphocytes, including the CD4(+) T cells that are the major cellular target for HIV infection. Mucosal surfaces are defended by innate and adaptive immune mechanisms, including secreted antibodies and CD8(+) cytotoxic T cells (CTL). CTL in mucosal lymphoid tissues may serve to limit viral replication, decreasing the host's viral burden as well as reducing the likelihood of sexual transmission to a naïve host. This review summarizes recent literature on HIV-specific T-cell responses in mucosal tissues, with an emphasis on the gastrointestinal tract.


Subject(s)
HIV Infections/immunology , HIV/immunology , Intestinal Mucosa/immunology , T-Lymphocytes/immunology , Animals , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , HIV Seronegativity/immunology , Humans
16.
Rev Med Interne ; 30(7): 630-3, 2009 Jul.
Article in French | MEDLINE | ID: mdl-18950905

ABSTRACT

Acquired haemophilia is a rare disorder caused by the development of autoantibody to factor VIII. It is sometimes associated with malignancies, and usually appears during disease course. In rare instances, acquired haemophilia is the presenting manifestation of a malignant disease. We report a 76-year-old man, who presented with spontaneous haematomas of his four limbs. A factor VIII inhibitor was found and the patient diagnosed with acquired haemophilia. Initial etiologic diagnostic workup including a thoracic and abdominal computed tomographic scan was negative. Factor VIII inhibitor disappeared on corticosteroids and factor VIII level normalized. Seven months later, the patient died from a multimetastatic cancer. About 15% of acquired haemophilia are associated with malignant disease (malignant lymphoma or solid neoplasia). Although rare, the development of a factor VIII inhibitor few months before the diagnosis of the malignant disease raised the issue of the appropriate initial investigations and further monitoring to recommend these patients. We propose a regular clinical monitoring and a thoracic and abdominal computed tomographic scan at six-month follow-up to screen for malignant disease.


Subject(s)
Hemophilia A/etiology , Neoplasm Metastasis/diagnosis , Paraneoplastic Syndromes/etiology , Aged , Autoantibodies/blood , Factor VIII/immunology , Humans , Male
17.
Rev Mal Respir ; 26(7): 783-7, 2009 Sep.
Article in French | MEDLINE | ID: mdl-19953022

ABSTRACT

We report the case of a 61-year old man in whom a deep venous thrombosis was the presenting feature of disseminated lung carcinoma. A few days later, an arterial thrombosis occurred necessitating amputation. Within a few weeks, the lung cancer progressed dramatically and the patient died. While the association between venous thrombosis and cancer is well known, the relationship between cancer and arterial thrombosis has been less explored. This observation allows discussion of the pathophysiological and clinical aspects of this association, as well as the implications for patient care.


Subject(s)
Carcinoma, Large Cell/complications , Femoral Artery , Femoral Vein , Iliac Artery , Lung Neoplasms/complications , Thrombophilia/complications , Thrombosis/etiology , Venous Thrombosis/etiology , Amputation, Surgical , Angiography , Biopsy , Carcinoma, Large Cell/diagnostic imaging , Carcinoma, Large Cell/pathology , Humans , Leg/blood supply , Leg/surgery , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Pleural Effusion/diagnostic imaging , Pleural Effusion/pathology , Radiography, Thoracic , Thrombosis/diagnostic imaging , Tomography, X-Ray Computed
20.
Sci Rep ; 8(1): 4119, 2018 Mar 07.
Article in English | MEDLINE | ID: mdl-29515179

ABSTRACT

We present an extended experimental study of the absolute yield of Kα x-ray source (17.48 keV) produced by interaction of an ultrahigh intensity femtosecond laser with solid Mo target for temporal contrast ratios in the range of 1.7 × 107-3.3 × 109 and on three decades of intensity 1016-1019 W/cm². We demonstrate that for intensity I ≥ 2 × 1018 W/cm² Kα x-ray emission is independent of the value of contrast ratio. In addition, no saturation of the Kα photon number is measured and a value of ~2 × 1010 photons/sr/s is obtained at 10 Hz and I ~1019 W/cm². Furthermore, Kα energy conversion efficiency reaches the same high plateau equal to ~2 × 10-4 at I = 1019 W/cm² for all the studied contrast ratios. This original result suggests that relativistic J × B heating becomes dominant in these operating conditions which is supposed to be insensitive to the electron density gradient scale length L/λ. Finally, an additional experimental study performed by changing the angle of incidence of the laser beam onto the solid target highlights a clear signature of the interplay between collisionless absorption mechanisms depending on the contrast ratio and intensity.

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