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We report on the observation of spontaneously drifting coupled spin and quadrupolar density waves in the ground state of laser driven Rubidium atoms. These laser-cooled atomic ensembles exhibit spontaneous magnetism via light mediated interactions when submitted to optical feedback by a retroreflecting mirror. Drift direction and chirality of the waves arise from spontaneous symmetry breaking. The observations demonstrate a novel transport process in out-of-equilibrium magnetic systems.
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We present experimental and theoretical results on formation of quantum vortices in a laser beam propagating in a nonlinear medium. Topological constrains richer than the mere conservation of vorticity impose an elaborate dynamical behavior to the formation and annihilation of vortex-antivortex pairs. We identify two such mechanisms, both described by the same fold-Hopf bifurcation. One of them is particularly efficient although it is not observed in the context of liquid helium films or stationary systems because it relies on the compressible nature of the fluid of light we consider and on the nonstationarity of its flow.
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BACKGROUND: A comparison of fusion rates and clinical outcomes of instrumented transforaminal interbody fusion (TLIF) between polyetheretherketone (PEEK) and titanium-coated PEEK (Ti-PEEK) cages is not well documented. METHODS: A single-centre, prospective, randomised study included patients who underwent one-level TLIF between L3-S1 segments. Patients were randomised into one of two groups: TLIF surgery with the PEEK cage and TLIF surgery with the Ti-PEEK cage. Clinical results were measured. All patients were assessed by repeated X-rays and 3D CT scans. Cage integration was assessed using a modified Bridwell classification. The impact of obesity and smoking on fusion quality was also analysed. Patients in both groups were followed up for 2 years. RESULTS: Altogether 87 patients were included in the study: of these 87 patients, 81 (93.1%) completed the 2-year follow-up. A significant improvement in clinical outcome was found in the two measurements scales in both groups (RM: p = 0.257, VAS: p = 0.229). There was an increase in CobbS and CobbL angle in both groups (p = 0.172 for CobbS and p = 0.403for CobbL). Bony fusion was achieved in 37 of 40 (92.5%) patients in the TiPEEK group and 35 of 41 (85.4%) in the PEEK group (p = 0.157). Cage subsided in 2 of 40 patients (5%) in the TiPEEK group and 11 of 41 (26.8%) in the PEEK group (p = 0.007). Body mass index > 30 and smoking were not predictive factors of bony fusion achievement. CONCLUSION: There is no significant advantage of TiPEEK cages over PEEK cages in clinical outcome and fusion rate 2 years after surgery.
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Benzofenonas , Polímeros , Fusión Vertebral , Titanio , Humanos , Vértebras Lumbares/cirugía , Estudios Prospectivos , Fusión Vertebral/métodos , Polietilenglicoles , Cetonas , Resultado del TratamientoRESUMEN
INTRODUCTION: It is often questioned whether to perform replantation or revision amputation for amputation injuries in elderly patients and smokers. According to the current indication criteria, neither old age nor smoking in the absence of other risk factors are considered to be risk factors for replantation failure. However, many microsurgeons still may make the decision not to perform digital replantation based solely on these factors. MATERIAL AND METHODS: In order to evaluate the influence of both factors, we provided univariate and multivariate analyses of patients who underwent replantation at our centre during a 10-year period. We divided patients in two groups according to age (< and ≥ 60 years) and smoking status. RESULTS: In the univariate analysis, there were no differences in immediate results between the two age groups. In the multivariate analysis, no statistical difference was found in neither long-term nor short-term results between the two age groups and between smokers and non-smokers. CONCLUSION: Smoking and age should not be considered the only risk factors when deciding whether to perform digital replantation.
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Fumar , Fumar Tabaco , Anciano , Humanos , Persona de Mediana Edad , Fumar/efectos adversos , Fumar/epidemiología , Análisis Multivariante , Amputación Quirúrgica , ReimplantaciónRESUMEN
PURPOSE OF THE STUDY This article presents the evidence and the rationale for the recommendations for surgical treatment of degenerative lumbar stenosis (DLS) and spondylolisthesis that were recently developed as a part of the Czech Clinical Practice Guideline (CPG) "The Surgical Treatment of the Degenerative Diseases of the Spine". MATERIAL AND METHODS The Guideline was drawn up in line with the Czech National Methodology of the CPG Development, which is based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. We used an innovative GRADE-adolopment method that combines adoption and adaptation of the existing guidelines with de novo development of recommendations. In this paper, we present three adapted recommendations on DLS and a recommendation on spondylolisthesis developed de novo by the Czech team. RESULTS Open surgical decompression in DLS patients has been evaluated in three randomized controlled trials (RCTs). A recommendation in favour of decompression was made based on a statistically significant and clinically evident improvement in the Oswestry Disability Index (ODI) and leg pain. Decompression may be recommended for patients with symptoms of DLS in the event of correlation of significant physical limitation and the finding obtained via imaging. The authors of a systematic review of observational studies and one RCT conclude that fusion has a negligible role in the case of a simple DLS. Thus, spondylodesis should only be chosen as an adjunct to decompression in selected DLS patients. Two RCTs compared supervised rehabilitation with home or no exercise, showing no statistically significant difference between the procedures. The guideline group considers the post-surgery physical activity beneficial and suggests supervised rehabilitation in patients who have undergone surgery for DLS for the beneficial effects of exercise in the absence of known adverse effects. Four RCTs were found comparing simple decompression and decompression with fusion in patients with degenerative lumbar spondylolisthesis. None of the outcomes showed clinically significant improvement or deterioration in favour of either intervention. The guideline group concluded that for stable spondylolisthesis the results of both methods are comparable and, when other parameters are considered (balance of benefits and risks, or costs), point in favour of simple decompression. Due to the lack of scientific evidence, no recommendation has been formulated regarding unstable spondylolisthesis. The certainty of the evidence was rated as low for all recommendations. DISCUSSION Despite the unclear definition of stable/unstable slip, the inclusion of apparently unstable cases of DS in stable studies limits the conclusions of the studies. Based on the available literature, however, it can be summarized that in simple degenerative lumbar stenosis and static spondylolisthesis, fusion of the given segment is not justified. However, its use in the case of unstable (dynamic) vertebral slip is undisputable for the time being. CONCLUSIONS The guideline development group suggests decompression in patients with DLS in whom previous conservative treatment did not lead to improvement, spondylodesis only in selected patients, and post-surgical supervised rehabilitation. In patients with degenerative lumbar stenosis and spondylolisthesis with no signs of instability, the guideline development group suggests simple decompression (without fusion). Key words: degenerative lumbar stenosis, degenerative spondylolisthesis, spinal fusion, Clinical Practice Guideline, GRADE, adolopment.
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Fusión Vertebral , Estenosis Espinal , Espondilolistesis , Humanos , Espondilolistesis/complicaciones , Espondilolistesis/cirugía , Constricción Patológica/cirugía , Estenosis Espinal/cirugía , Vértebras Lumbares/cirugía , Descompresión Quirúrgica/métodos , Resultado del TratamientoRESUMEN
AIMS: To evaluate the efficacy and safety of nintedanib plus docetaxel in patients with advanced adenocarcinoma non-small cell lung cancer (NSCLC) who progressed after chemotherapy and immune checkpoint inhibitor (ICI) therapy. MATERIALS AND METHODS: VARGADO (NCT02392455) is an ongoing, prospective, non-interventional, real-world study of nintedanib plus docetaxel after first-line chemotherapy in the routine clinical treatment of patients with locally advanced, metastatic or locally recurrent adenocarcinoma NSCLC. Data were collected during routine visits. We report the results from cohort B (n = 80), who received third-line nintedanib plus docetaxel after first-line chemotherapy and second-line ICI therapy. RESULTS: The median duration of follow-up was 12.4 months. Median progression-free survival from initiation of third-line nintedanib plus docetaxel was 6.4 months (95% confidence interval 4.8, 7.3); median overall survival was 12.1 months (95% confidence interval 9.4, 13.5). The 1-year overall survival rate after initiation of third-line nintedanib plus docetaxel treatment (primary end point) was 52% (95% confidence interval 38.0%, 64.4%). Among 64 patients with a documented response, the objective response rate was 50% (n = 32; one complete response and 31 partial responses) and the disease control rate was 86% (n = 55). There were no new safety signals or unexpected toxicities. Among all treated patients, 74% (n = 59) experienced drug-related adverse events, most commonly (nintedanib-related/docetaxel-related) diarrhoea (34%/24%), a decreased white blood cell count (11%/19%) and nausea (13%/16%). CONCLUSIONS: Nintedanib plus docetaxel demonstrated a high response rate and disease stabilisation in the third-line setting after failure of prior chemotherapy and ICI treatment, with a manageable safety profile. These results suggest that nintedanib plus docetaxel represents an efficient treatment option after failure of prior ICIs. The ongoing VARGADO study provides valuable real-world data to inform clinical decision-making regarding treatment sequencing after chemotherapy and ICI failure in patients with adenocarcinoma NSCLC.
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Adenocarcinoma , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adenocarcinoma/patología , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/patología , Docetaxel , Humanos , Inhibidores de Puntos de Control Inmunológico , Indoles , Neoplasias Pulmonares/patología , Recurrencia Local de Neoplasia/tratamiento farmacológico , Estudios Prospectivos , Resultado del TratamientoRESUMEN
We report the first measurement of the average of the electron-proton and positron-proton elastic scattering cross sections. This lepton charge-averaged cross section is insensitive to the leading effects of hard two-photon exchange, giving more robust access to the proton's electromagnetic form factors. The cross section was extracted from data taken by the OLYMPUS experiment at DESY, in which alternating stored electron and positron beams were scattered from a windowless gaseous hydrogen target. Elastic scattering events were identified from the coincident detection of the scattered lepton and recoil proton in a large-acceptance toroidal spectrometer. The luminosity was determined from the rates of Møller, Bhabha, and elastic scattering in forward electromagnetic calorimeters. The data provide some selectivity between existing form factor global fits and will provide valuable constraints to future fits.
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We report on an experimental study of photon thermalization and condensation in a semiconductor microresonator in the weak-coupling regime. We measure the dispersion relation of light and the photon mass in a single-wavelength, broad-area resonator. The observed luminescence spectrum is compatible with a room-temperature, thermal-equilibrium distribution. A phase transition, identified by a saturation of the population at high energies and a superlinear increase of the occupation at low energy, takes place when the phase-space density is of order unity. We explain our observations by Bose-Einstein condensation of photons in equilibrium with a particle reservoir and discuss the relation with laser emission.
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Dipole-dipole interactions are at the origin of long-lived collective atomic states, often called subradiant, which are explored for their potential use in novel photonic devices or in quantum protocols. Here, we study subradiance beyond the single-excitation regime and experimentally demonstrate a 200-fold increase in the population of these modes, as the saturation parameter of the driving field is increased. We attribute this enhancement to a mechanism similar to optical pumping through the well-coupled superradiant states. The lifetimes are unaffected by the pump strength, as the system is ultimately driven toward the single-excitation sector. Our study is a new step in the exploration of the many-body dynamics of large open systems.
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PURPOSE: To predict the course of immune recovery (IR) in HIV-1-infected patients after initiation of combined antiretroviral therapy (cART) by determination of the plasma concentration of Torque Teno Virus (TTV). TTV has been identified as marker for risk assessment in immunosuppressed patients after transplantation procedures. Here, TTV was analyzed in HIV-1-infected therapy-naïve patients to evaluate its use as predictor of the course of IR for guidance of individualized treatment. METHODS: TTV DNA was quantified in plasma samples of 301 therapy-naïve HIV-1-infected patients and correlated to CD4+ cell count, HIV viral load, presence of the herpes viruses CMV, EBV and HHV-8, age and sex. Patients were classified according to their initial CD4+ cell count and to the extent of CD4+ T-cell increase within the first year of cART. RESULTS: TTV DNA was detectable in 96% of the patients' plasma samples with a median TTV plasma concentration of 5.37 log10 cop/ml. The baseline CD4+ cell count was negatively correlated with TTV plasma concentration (p = 0.003). In patients with a CD4+ cell recovery < 50 cells/µl, the median TTV plasma concentration was significantly higher compared to patients with a CD4+ cell recovery of > 200 CD4+ cells/µl (5.68 log10 cop/ml versus 4.99 log10 cop/ml; p = 0.011). TTV plasma concentration in combination with baseline CD4+ cell count were significantly correlated to CD4+ cell recovery (p = 0.004). For all other parameters considered, no significant correlation for CD4+ cell recovery was found. CONCLUSION: Within the cohort, the significantly elevated TTV plasma concentration in patients with diminished CD4+ cell recovery indicates a more profound immune defect. Baseline TTV plasma concentrations and CD4+ cell count are predictive for the course of immune recovery in HIV-1-infected patients with severe immunodeficiency.
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Infecciones por Virus ADN , Infecciones por VIH , Torque teno virus , Biomarcadores , ADN Viral , Infecciones por VIH/tratamiento farmacológico , Humanos , Inmunocompetencia , Torque teno virus/genética , Carga ViralRESUMEN
We show that induced dipole-dipole interactions allow for photon blockade in subwavelength ensembles of two-level, ground-state neutral atoms. Our protocol relies on the energy shift of the single-excitation, superradiant state of N atoms, which can be engineered to yield an effective two-level system. A coherent pump induces Rabi oscillation between the ground state and a collective bright state, with at most a single excitation shared among all atoms. The possibility of using clock transitions that are long-lived and relatively robust against stray fields, alongside new prospects on experiments with subwavelength lattices, makes our proposal a promising alternative for quantum information protocols.
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BACKGROUND: Pre-treatment drug resistance (PDR) among antiretroviral drug-naïve people living with HIV (PLHIV) represents an important indicator for the risk of treatment failure and the spread of drug resistant HIV variants. We assessed the prevalence of PDR and treatment outcomes among adults living with HIV-1 in Lilongwe, Malawi. METHODS: We selected 200 participants at random from the Lighthouse Tenofovir Cohort Study (LighTen). Serum samples were drawn prior to treatment initiation in 2014 and 2015, frozen, and later analyzed for the presence of HIV-1 drug resistance mutations. Amplicons were sequenced and interpreted by Stanford HIVdb interpretation algorithm 8.4. We assessed treatment outcomes by evaluating clinical outcome and viral suppression at the end of the follow-up period in October 2019. RESULTS: PDR testing was successful in 197 of 200 samples. The overall NNRTI- PDR prevalence was 13.7% (27/197). The prevalence of intermediate or high level NNRTI- PDR was 11.2% (22/197). The most common mutation was K103N (5.6%, 11/197), followed by Y181C (3.6%, 7/197). In one case, we detected an NRTI resistance mutation (M184V), in combination with multiple NNRTI resistance mutations. All HIV-1 isolates analyzed were of subtype C. Of the 27 patients with NNRTI- PDR, 9 were still alive, on ART, and virally suppressed at the end of follow-up. CONCLUSION: The prevalence of NNRTI- PDR was above the critical level of 10% suggested by the Global Action Plan on HIV Drug Resistance. The distribution of drug resistance mutations was similar to that seen in previous studies from the region, and further supports the introduction of integrase inhibitors in first-line treatment in Malawi. Furthermore, our findings underline the need for continued PDR surveillance and pharmacovigilance in Sub-Saharan Africa.
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Farmacorresistencia Viral/genética , VIH-1/efectos de los fármacos , VIH-1/genética , Población Urbana/estadística & datos numéricos , Adulto , Fármacos Anti-VIH/uso terapéutico , Estudios de Cohortes , Esquema de Medicación , Femenino , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Malaui/epidemiología , Masculino , Persona de Mediana Edad , Mutación , Prevalencia , Insuficiencia del Tratamiento , Resultado del Tratamiento , Carga Viral/efectos de los fármacosRESUMEN
The main goal of this comprehensive paper is to clarify the way of thoracolumbar spine The main goal of this summary paper is to describe the way of thoracolumbar spine injury classification development and to provide a detailed description of two of the most commonly used classifications - the Thoracolumbar Injury Classification and Severity Scale (TLICS) and the AOSpine Classification for Traumatic Fracture of the Thoracolumbar Spine, including their comparison and clarification of the merits introduced by the second one. The paper also formulates a recommendation of a simple algorithm enabling even less experienced clinicians to distinguish between an injury indicated for conservative treatment and one that requires surgery.
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Fracturas de la Columna Vertebral/cirugía , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/lesiones , Tratamiento Conservador , Humanos , Puntaje de Gravedad del Traumatismo , Vértebras Lumbares/diagnóstico por imagenRESUMEN
INTRODUCTION: Chronic back pain (CBP) is a very common symptom. Multiple modalities are used in its evaluation. However, according to current evidence, none of them can be used with certainty to predict the success of fusion surgery. Given the growing experience with bone tissue examination using the methods of nuclear medicine, we have used this possibility in patients with CBP without disc herniation, degenerative spinal stenosis or instability. CASE REPORTS: We present case reports of 11 patients who underwent lumbar fusion (during two years period) for degenerative disc disease or facet arthropathy with adequate activity on PET or SPECT/CT examination. Rolland-Morris Questionnaire (RMQ), Oswestry Disability Index (ODI), and Visual Analogue Scale (VAS) were filled out pre-operatively and 24 months after surgery. RESULTS: Six patients after one-level stabilization for active osteochondrosis and one for active facet arthropathy improved on average by 82% (64-92%) in RMQ, by 72% (48-100%) in ODI and 75% (55-100%) in VAS. Results in cases after multilevel stabilizations were slightly worse, but still very significant in most parameters. Only one patient with the most severe morphological and clinical findings did not benefit from surgery. CONCLUSION: In 10 out of 11 patients, the lower back pain and quality of life improved significantly after lumbar fusion performed in levels diagnosed by PET or SPECT/CT. These methods certainly have their place in the evaluation of CBP, especially in the case of unclear findings or multiple degenerative changes.
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Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/cirugía , Medicina Nuclear , Fusión Vertebral , Estenosis Espinal/cirugía , Humanos , Vértebras Lumbares/diagnóstico por imagen , Calidad de Vida , Resultado del TratamientoRESUMEN
Using a model system, we demonstrate both experimentally and theoretically that coherent scattering of light can be robust in hot atomic vapors despite a significant Doppler effect. By operating in a linear regime of far-detuned light scattering, we also unveil the emergence of interference triggered by inelastic Stokes and anti-Stokes transitions involving the atomic hyperfine structure.
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High-performance thin-layer chromatography (HPTLC) methods were developed to determine glycerol, gluconic acid, amino acids and sugars for in-process quality control of wine. Twenty wine samples (Pfalz region, Germany) were diluted with methanol and used for quantitative analysis without any further sample preparation. The developed amino acid method provided quantitative and characteristic fingerprints of wine varieties. The amino acid assignments were verified by HPTLC-MS. The developed gluconic acid method was primarily used to control the threshold, indicating a Botrytis cinerea infection of grapes. However, this method also enabled the detection of further organic acids like malic, tartaric and citric acids. A glycerol method was developed for control of the grape must fermentation (spontaneous/regular) and for fraud detection (glycerol adulteration). The HPTLC results of the sugar contents in the wine samples were similar to those of the well-known Luff-Schoorl method. The combined use of these developed HPTLC methods allowed the fermentation control (e.g., alcoholic and malolactic fermentation) and the monitoring of the grapes' overall health status. Without modification, the HPTLC methods for sugar and amino acid analysis could be transferred to circular micro planar chromatography (µ-PLC), showing its potential and benefits in terms of an inexpensive alternative for wineries and distributors.
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Cromatografía en Capa Delgada , Análisis de los Alimentos/métodos , Control de Calidad , Vino/análisis , Vino/normas , Botrytis/química , Carbohidratos/análisis , Fermentación , Alemania , Glicerol/análisis , Vitis/química , Vitis/microbiologíaRESUMEN
We report the experimental observation of collective multimode vacuum Rabi splitting in free space. In contrast to optical cavities, the atoms couple to a continuum of modes, and the optical thickness of the cloud provides a measure of this coupling. The splitting, also referred as normal mode splitting, is monitored through the Rabi oscillations in the scattered intensity, and the results are fully explained by a linear-dispersion theory.
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Meralgia paresthetica is a compression neuropathy of the lateral femoral cutaneous nerve. Despite its rarity, it is the most common nerve entrapment of the lower limbs. It produces similar symptoms as those associated with the more common L4 or L5 radiculopathy. Therefore, it is often diagnosed late (sometimes only after several years of latency) or not at all. This diagnosis should be considered especially in patients with obesity and diabetes who have chronic irritation of the ventrolateral areas of the thigh not responding to conservative therapy and a negative finding on lumbar MRI. We present our experience with surgical nerve decompression in three patients with pain, paresthesias, and sensory loss within the distribution of the lateral cutaneous nerve of the thigh. They all suffered from severe abdominal obesity. All conservative treatments, including weight reduction attempts, were unsuccessful. Nerve release caused an immediate effect in two cases. One patient experienced a temporary worsening of pain, which gradually improved within one month. In spite of the controversy surrounding the surgical treatment of meralgia (neurolysis or nerve resection), it can be concluded that nerve decompression has a good effect. Nerve resection is, in our view, considered to be a reserve option when primary surgery fails. Key words: meralgia paresthetica - nerve entrapment - peripheral nerve.
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Neuropatía Femoral , Síndromes de Compresión Nerviosa , Neuropatía Femoral/diagnóstico , Neuropatía Femoral/terapia , Humanos , Plexo Lumbosacro , Síndromes de Compresión Nerviosa/diagnóstico , Síndromes de Compresión Nerviosa/terapia , Parestesia , MusloRESUMEN
Computational fluid dynamics (CFD) simulations and isothermal approximation were applied for the interpretation of experimental measurements of the C10H7Br pyrolysis efficiency in the high-temperature microreactor and of the pressure drop in the flow tube of the reactor. Applying isothermal approximation allows the derivation of analytical relationships between the kinetic, gas flow, and geometrical parameters of the microreactor, which, along with CFD simulations, accurately predict the experimental observations. On the basis of the obtained analytical relationships, a clear strategy for measuring rate coefficients of (pseudo) first-order bimolecular and unimolecular reactions using the microreactor was proposed. The pressure- and temperature-dependent rate coefficients for the C10H7Br pyrolysis calculated using variable reaction coordinate transition state theory were invoked to interpret the experimental data on the pyrolysis efficiency.