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BACKGROUND: Clinical trials have shown reduced incisional hernia rates 1 year after elective median laparotomy closure using a short-stitch technique. With hernia development continuing beyond the first postoperative year, we aimed to compare incisional hernias 3 years after midline closure using short or long stitches in patients from the ESTOIH trial. METHODS: The ESTOIH trial was a prospective, multicenter, parallel-group, double-blind, randomized-controlled study of primary elective midline closure. Patients were randomized to fascia closure using a short- or long-stitch technique with a poly-4-hydroxybutyrate-based suture. A predefined 3-year follow-up analysis was performed with the radiological imaging-verified incisional hernia rate as the primary endpoint. RESULTS: The 3-year intention-to-treat follow-up cohort consisted of 414 patients (210 short-stitch and 204 long-stitch technique) for analysis. Compared with 1 year postoperatively, incisional hernias increased from 4.83% (20/414 patients) to 9.02% (36/399 patients, p = 0.0183). The difference between the treatment groups at 3 years (short vs. long stitches, 15/198 patients (7.58%) vs. 21/201 (10.45%)) was not significant (OR, 1.4233; 95% CI [0.7112-2.8485]; p = 0.31). CONCLUSION: Hernia rates increased significantly between one and 3 years postoperatively. The short-stitch technique using a poly-4-hydroxybutyrate-based suture is safe in the long term, while no significant advantage was found at 3 years postoperatively compared with the standard long-stitch technique. TRIAL REGISTRY: NCT01965249, registered on 18 October 2013.
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Técnicas de Cierre de Herida Abdominal , Procedimientos Quirúrgicos Electivos , Hernia Incisional , Técnicas de Sutura , Humanos , Femenino , Masculino , Hernia Incisional/cirugía , Persona de Mediana Edad , Estudios de Seguimiento , Método Doble Ciego , Anciano , Estudios Prospectivos , Hernia Ventral/cirugía , Hidroxibutiratos , Suturas , PoliésteresRESUMEN
PURPOSE: The short-stitch technique for midline laparotomy closure has been shown to reduce hernia rates, but long stitches remain the standard of care and the effect of the short-stitch technique on short-term results is not well known. The aim of this study was to compare the two techniques, using an ultra-long-term absorbable elastic suture material. METHODS: Following elective midline laparotomy, 425 patients in 9 centres were randomised to receive wound closure using the short-stitch (USP 2-0 single thread, n = 215) or long-stitch (USP 1 double loop, n = 210) technique with a poly-4-hydroxybutyrate-based suture material (Monomax®). Here, we report short-term surgical outcomes. RESULTS: At 30 (+10) days postoperatively, 3 (1.40%) of 215 patients in the short-stitch group and 10 (4.76%) of 210 patients in the long-stitch group had developed burst abdomen [OR 0.2830 (0.0768-1.0433), p = 0.0513]. Ruptured suture, seroma and hematoma and other wound healing disorders occurred in small numbers without differences between groups. In a planned Cox proportional hazard model for burst abdomen, the short-stitch group had a significantly lower risk [HR 0.1783 (0.0379-0.6617), p = 0.0115]. CONCLUSIONS: Although this trial revealed no significant difference in short-term results between the short-stitch and long-stitch techniques for closure of midline laparotomy, a trend towards a lower rate of burst abdomen in the short-stitch group suggests a possible advantage of the short-stitch technique. TRIAL REGISTRY: NCT01965249, registered October 18, 2013.
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Técnicas de Cierre de Herida Abdominal , Abdomen , Técnicas de Cierre de Herida Abdominal/efectos adversos , Herniorrafia , Humanos , Laparotomía/efectos adversos , Laparotomía/métodos , Técnicas de Sutura , SuturasRESUMEN
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The extended Bose-Hubbard model captures the essential properties of a wide variety of physical systems including ultracold atoms and molecules in optical lattices, Josephson junction arrays, and certain narrow band superconductors. It exhibits a rich phase diagram including a supersolid phase where a lattice solid coexists with a superfluid. We use quantum Monte Carlo to study the supersolid part of the phase diagram of the extended Bose-Hubbard model on the simple cubic lattice. We add disorder to the extended Bose-Hubbard model and find that the maximum critical temperature for the supersolid phase tends to be suppressed by disorder. But we also find a narrow parameter window in which the supersolid critical temperature is enhanced by disorder. Our results show that supersolids survive a moderate amount of spatial disorder and thermal fluctuations in the simple cubic lattice.
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Heavily electron-doped iron-selenide high-transition-temperature (high-T c) superconductors, which have no hole Fermi pockets, but have a notably high T c, have challenged the prevailing s ± pairing scenario originally proposed for iron pnictides containing both electron and hole pockets. The microscopic mechanism underlying the enhanced superconductivity in heavily electron-doped iron-selenide remains unclear. Here, we used neutron scattering to study the spin excitations of the heavily electron-doped iron-selenide material Li0.8Fe0.2ODFeSe (T c = 41 K). Our data revealed nearly ring-shaped magnetic resonant excitations surrounding (π, π) at â¼21 meV. As the energy increased, the spin excitations assumed a diamond shape, and they dispersed outward until the energy reached â¼60 meV and then inward at higher energies. The observed energy-dependent momentum structure and twisted dispersion of spin excitations near (π, π) are analogous to those of hole-doped cuprates in several aspects, thus implying that such spin excitations are essential for the remarkably high T c in these materials.The microscopic mechanism underlying an enhanced superconductivity in electron-doped iron selenide superconductor remains unclear. Here, Pan et al. report the spin excitations of Li0.8Fe0.2ODFeSe, revealing analogous momentum structure and dispersion to hole-doped cuprates.
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Bulk rutile RuO_{2} has long been considered a Pauli paramagnet. Here we report that RuO_{2} exhibits a hitherto undetected lattice distortion below approximately 900 K. The distortion is accompanied by antiferromagnetic order up to at least 300 K with a small room temperature magnetic moment of approximately 0.05µ_{B} as evidenced by polarized neutron diffraction. Density functional theory plus U (DFT+U) calculations indicate that antiferromagnetism is favored even for small values of the Hubbard U of the order of 1 eV. The antiferromagnetism may be traced to a Fermi surface instability, lifting the band degeneracy imposed by the rutile crystal field. The combination of high Néel temperature and small itinerant moments make RuO_{2} unique among ruthenate compounds and among oxide materials in general.
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BACKGROUND: Exposure to trauma was found to increase later violent behaviours in youth but the underlying psychopathological mechanisms are unclear. This study aimed to test whether posttraumatic stress disorder (PTSD) is related to violent behaviours and whether PTSD symptoms mediate the relationship between the number of trauma experiences and violent behaviours in adolescents. METHOD: The present study is based on a nationally representative sample of 9th grade students with 3434 boys (mean age=15.5 years) and 3194 girls (mean age=15.5 years) in Switzerland. Lifetime exposure to traumatic events and current PTSD were assessed by the use of the University of California at Los Angeles Posttraumatic Stress Disorder Reaction Index (UCLA-RI). Logistic regression was used to assess associations between PTSD and violent behaviours, and structural equation modelling (SEM) was used to examine the meditation effects of PTSD. RESULTS: PTSD (boys: OR=7.9; girls: OR=5.5) was strongly related to violent behaviours. PTSD symptoms partially mediated the association between trauma exposure and violent behaviours in boys but not in girls. PTSD symptoms of dysphoric arousal were positively related to violent behaviours in both genders. Anxious arousal symptoms were negatively related to violent behaviours in boys but not in girls. CONCLUSIONS: In addition to trauma, posttraumatic stress is related to violent outcomes. However, specific symptom clusters of PTSD seem differently related to violent behaviours and they do not fully explain a trauma-violence link. Specific interventions to improve emotion regulation skills may be useful particularly in boys with elevated PTSD dysphoric arousal in order to break up the cycle of violence.
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Agresión/psicología , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/psicología , Estudiantes/psicología , Violencia/psicología , Adolescente , Ansiedad/diagnóstico , Nivel de Alerta/fisiología , Estudios Transversales , Emociones , Femenino , Humanos , Masculino , Psicología del Adolescente , Estudiantes/estadística & datos numéricos , SuizaRESUMEN
In unconventional superconductors, understanding the form of the pairing interaction is the primary goal. In this regard, Raman spectroscopy is a very useful tool, as it identifies the ground state and also the subleading pairing channels by probing collective modes. Here, we propose a general theory for a multiband Raman response and identify new features in the spectrum that can provide a robust test for a pairing theory. We identify multiple Bardasis-Schrieffer type collective modes and connect the weights of these modes to the subleading gap structures within a microscopic pairing theory. While our conclusions are completely general, we apply our approach to interpret the specific case of B_{1g} Raman scattering in hole-doped BaFe_{2}As_{2}.
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In the traditional Bardeen-Cooper-Schrieffer theory of superconductivity, the amplitude for the propagation of a pair of electrons with momentum k and -k has a log singularity as the temperature decreases. This so-called Cooper instability arises from the presence of an electron Fermi sea. It means that an attractive interaction, no matter how weak, will eventually lead to a pairing instability. However, in the pseudogap regime of the cuprate superconductors, where parts of the Fermi surface are destroyed, this log singularity is suppressed, raising the question of how pairing occurs in the absence of a Fermi sea. Here we report Hubbard model numerical results and the analysis of angular-resolved photoemission experiments on a cuprate superconductor. In contrast to the traditional theory, we find that in the pseudogap regime the pairing instability arises from an increase in the strength of the spin-fluctuation pairing interaction as the temperature decreases rather than the Cooper log instability.
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Moulds or non-dermatophyte moulds (NDM) are being increasingly isolated as causative agent of onychomycoses. Known causes of a NDM-OM are Scopulariopsis brevicaulis, Fusarium, Aspergillus, Acremonium, Neoscytalidium dimidiatum, Arthrographis kalrae, and Chaetomium. In this article, 5 patients with suspected nail infection due to Onychocola canadensis are reported for the first time in Germany. Systemic antifungal agents are not considered to be effective in NDM onychomycosis. In individual cases, however, terbinafine seems to be effective in Onychocola canadensis infection of the nails. Treatment of choice represents, however, nontraumatic nail avulsion using 40 % urea ointment followed by antifungal nail lacquer with ciclopirox olamine or amorolfine.
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Naftalenos/uso terapéutico , Onicomicosis/diagnóstico , Onicomicosis/tratamiento farmacológico , Onygenales/aislamiento & purificación , Anciano , Antifúngicos/uso terapéutico , Enfermedades Transmisibles Emergentes/diagnóstico , Enfermedades Transmisibles Emergentes/tratamiento farmacológico , Enfermedades Transmisibles Emergentes/microbiología , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Onicomicosis/microbiología , Terbinafina , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: The cation channel transient receptor potential canonical (TRPC) 6 has been associated with several pathologies including focal segmental glomerulosclerosis, pulmonary hypertension and ischaemia reperfusion-induced lung oedema. We set out to discover novel inhibitors of TRPC6 channels and investigate the therapeutic potential of these agents. EXPERIMENTAL APPROACH: A library of potential TRPC channel inhibitors was designed and synthesized. Activity of the compounds was assessed by measuring intracellular Ca(2+) levels. The lead compound SAR7334 was further characterized by whole-cell patch-clamp techniques. The effects of SAR7334 on acute hypoxic pulmonary vasoconstriction (HPV) and systemic BP were investigated. KEY RESULTS: SAR7334 inhibited TRPC6, TRPC3 and TRPC7-mediated Ca(2+) influx into cells with IC50 s of 9.5, 282 and 226 nM, whereas TRPC4 and TRPC5-mediated Ca(2+) entry was not affected. Patch-clamp experiments confirmed that the compound blocked TRPC6 currents with an IC50 of 7.9 nM. Furthermore, SAR7334 suppressed TRPC6-dependent acute HPV in isolated perfused lungs from mice. Pharmacokinetic studies of SAR7334 demonstrated that the compound was suitable for chronic oral administration. In an initial short-term study, SAR7334 did not change mean arterial pressure in spontaneously hypertensive rats (SHR). CONCLUSIONS AND IMPLICATIONS: Our results confirm the role of TRPC6 channels in hypoxic pulmonary vasoregulation and indicate that these channels are unlikely to play a major role in BP regulation in SHR. SAR7334 is a novel, highly potent and bioavailable inhibitor of TRPC6 channels that opens new opportunities for the investigation of TRPC channel function in vivo.
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Diglicéridos/farmacología , Descubrimiento de Drogas , Indanos/farmacología , Canales Catiónicos TRPC/antagonistas & inhibidores , Células Cultivadas , Diglicéridos/síntesis química , Diglicéridos/química , Relación Dosis-Respuesta a Droga , Humanos , Indanos/síntesis química , Indanos/química , Datos de Secuencia Molecular , Estructura Molecular , Relación Estructura-Actividad , Canales Catiónicos TRPC/metabolismoRESUMEN
We consider the effect of glide-plane symmetry of the Fe-pnictogen/chalcogen layer in Fe-based superconductors on pairing in spin fluctuation models. Recent theories have proposed that so-called η-pairing states with nonzero total momentum can be realized and possess exotic properties such as odd parity spin singlet symmetry and time-reversal symmetry breaking. Here we show that η pairing is inevitable when there is orbital weight at the Fermi level from orbitals with even and odd mirror reflection symmetry in z; however, by explicit calculation, we conclude that the gap function that appears in observable quantities is identical to that found in earlier, 1 Fe per unit cell pseudocrystal momentum calculations.
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We show that for ultracold magnetic lanthanide atoms chaotic scattering emerges due to a combination of anisotropic interaction potentials and Zeeman coupling under an external magnetic field. This scattering is studied in a collaborative experimental and theoretical effort for both dysprosium and erbium. We present extensive atom-loss measurements of their dense magnetic Feshbach-resonance spectra, analyze their statistical properties, and compare to predictions from a random-matrix-theory-inspired model. Furthermore, theoretical coupled-channels simulations of the anisotropic molecular Hamiltonian at zero magnetic field show that weakly bound, near threshold diatomic levels form overlapping, uncoupled chaotic series that when combined are randomly distributed. The Zeeman interaction shifts and couples these levels, leading to a Feshbach spectrum of zero-energy bound states with nearest-neighbor spacings that changes from randomly to chaotically distributed for increasing magnetic field. Finally, we show that the extreme temperature sensitivity of a small, but sizable fraction of the resonances in the Dy and Er atom-loss spectra is due to resonant nonzero partial-wave collisions. Our threshold analysis for these resonances indicates a large collision-energy dependence of the three-body recombination rate.
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BACKGROUND AND OBJECTIVES: After permanent make-up treatments, eczematous and granulomatous reactions may occur which need anti-inflammatory treatment. For the definite diagnosis oftentimes biopsies are recommended. In vivo imaging such as reflectance confocal microscopy (RCM) and high-definition optical coherence tomography (HD-OCT) has been successfully used in the non-invasive diagnosis of various dermatoses before. METHODS: Here, we report on non-invasive imaging of a reaction towards permanent make-up in a 40-year-old woman by using HD-OCT and RCM. RESULTS: Both in HD-OCT and in RCM subepidermal pigment and granulomatous changes could be visualized and correlated with the histopathological findings. Regression of the lesions in response to topical steroids and intralesional injections of steroids and 5-fluorouracil is reported and treatment options are discussed. CONCLUSION: Non-invasive imaging techniques such as HD-OCT and RCM allow the visualization and localization of exogenous pigment and help in the evaluation of adverse reactions due to permanent make-up tattooing.
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Cosméticos , Microscopía Confocal , Tomografía de Coherencia Óptica , Adulto , Femenino , HumanosRESUMEN
BACKGROUND: Lately, various smartphone applications have been introduced as diagnostic self-monitoring tools in the evaluation of pigmented moles, but most of these techniques have not been evaluated systematically. OBJECTIVES: The purpose of this study was to evaluate prospectively the sensitivity and specificity of a recently developed smartphone application using fractal image analysis for the risk evaluation algorithm in the diagnosis of malignant melanoma compared to clinical diagnosis and histopathological result. METHODS: Consecutive patients with melanocytic lesions were recruited and clinical and dermoscopical diagnosis was documented by two dermatologists independently. Imaging and analysis with the smartphone application was performed prior to excision of lesions. The findings were compared to the histological results as gold standard. RESULTS: Of 195 included lesions histopathological analysis revealed 40 melanomas, 42 dysplastic nevi and 113 benign nevi. The sensitivity of the diagnosis melanoma by fractal image analysis using smartphone images was 73%, the specificity was 83% compared to a sensitivity of 88% and specificity of 97% regarding the clinical diagnosis by the dermatologists. CONCLUSION: The smartphone application using fractal analysis might be a promising tool in the pre-evaluation of pigmented moles by laypersons, while it is to date inferior to the diagnostic evaluation by a dermatologist.
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Fractales , Procesamiento de Imagen Asistido por Computador , Melanoma/patología , Aplicaciones Móviles , Nevo Pigmentado/patología , Neoplasias Cutáneas/patología , Teléfono Inteligente , Algoritmos , Dermoscopía , Humanos , Melanoma/cirugía , Nevo Pigmentado/cirugía , Estudios Prospectivos , Medición de Riesgo/métodos , Sensibilidad y Especificidad , Neoplasias Cutáneas/cirugíaRESUMEN
BACKGROUND: High-definition optical coherence tomography scanners have recently been developed. OBJECTIVES: To assess the diagnostic performance of HD-OCT in the differentiation of benign melanocytic skin lesions (MSL) and cutaneous melanoma (CM). METHODS: Patients with MSL were assessed by HD-OCT. All diagnoses were histopathologically confirmed. One blinded observer evaluated both slice and en-face HD-OCT images and diagnosed MLS on the basis of an algorithm adopted from reflectance confocal microscopy, recent HD-OCT reports, and conventional OCT. RESULTS: A total of 93 MSL were studied comprising 66 benign MSL and 27 CM. The sensitivity of HD-OCT was 74.1% [95% confidence interval (CI) 53.7-88.8%)], specificity was 92.4% (95% CI 83.2-97.5%). The positive predictive value was 80%, the negative predictive value 89.7%. The performance of HD-OCT depended on tumour thickness and the presence of borderline lesions indicated by high false negative rates in very thin melanomas and high false positive rates in dysplastic naevi. CONCLUSIONS: In the distinction of MSL, HD-OCT applied in an investigator blinded fashion has a moderate diagnostic performance. The diagnostic performance of HD-OCT of MSL should be reassessed in other clinical settings.
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Melanoma/diagnóstico , Nevo Pigmentado/diagnóstico , Neoplasias Cutáneas/diagnóstico , Tomografía de Coherencia Óptica , Diagnóstico Diferencial , Humanos , Proyectos PilotoRESUMEN
We present our technique to create a magneto-optical trap (MOT) for dysprosium atoms using the narrow-line cooling transition at 626 nm to achieve suitable conditions for direct loading into an optical dipole trap. The MOT is loaded from an atomic beam via a Zeeman slower using the strongest atomic transition at 421 nm. With this combination of two cooling transitions we can trap up to 2.0·10(8) atoms at temperatures down to 6 µK. This cooling approach is simpler than present work with ultracold dysprosium and provides similar starting conditions for a transfer to an optical dipole trap.
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BACKGROUND: In 1969, Kolipp and Hoffmann isolated Trichophyton (T.) thuringiense spec. nov. Koch when they performed their thesis dealing with the distribution and epidemiology of dermatophytes and keratinophilic fungi in mice and other small mammals. At that time, T. thuringiense was detected as saprophytic fungus of the skin of different mice species (e.g. Mus musculus) both in rural and urban settings in the area of Thuringia in Germany. There were no further reports on this dermatophyte species until now, neither in animals, nor in man. PATIENT, METHODS AND RESULTS: Currently, we were able to isolate this geophilic fungus for the first time from a human being. A 58 year old patient baker by trade and living in a rural setting (village) suffered from nail changes like hyperkeratosis and thickening of the nail plate of his big toe. From his nail samples grew a dermatophyte with peripheral radiating and flat colonies which were a bit cottony in the centre. On Sabouraud's 4 % dextrose agar the thallus of the fungus was white to purple stained, the reverse side showed a dark red to brown color. In a typical manner, macroconidia were cylindrical to clavate, microconidia obovoidal to short-clavate with broad base. The species identification of T. thuringiense was done and confirmed by sequence analysis of the internal transcribed spacer (ITS) region of the ribosomal DNA. Antifungal treatment has been refused from the patient. CONCLUSION: In conclusion, this is the second description of the geophilic dermatophyte T. thuringiense, which could be isolated for the first time from a human being, in particular from nail sample of the big toe under the suspicion of onychomycosis. However, it is still uncertain if this fungus should be considered either as secondary colonization of the nail plate, or as causative agent of tinea unguium or onychomycosis.
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Arthrodermataceae/clasificación , Arthrodermataceae/aislamiento & purificación , Tiña/microbiología , Trichophyton/clasificación , Trichophyton/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Raras/diagnóstico , Enfermedades Raras/microbiología , Tiña/diagnósticoRESUMEN
BACKGROUND: Micrographic surgery is an established, but time-consuming operating procedure for facial basal cell carcinoma (BCC). A new high-definition (HD) optical coherence tomography (OCT) with high lateral and axial resolution in a horizontal (en-face) and vertical (slice) imaging mode allows a fast and non-invasive in vivo examination of BCC. OBJECTIVES: To compare the diagnosis of BCC in excised tissue ex vivo by high-definition optical coherence tomography (HD-OCT) with the findings of frozen-section histology in micrographic surgery. METHODS: Twenty freshly excised BCC were examined by HD-OCT in the en-face and slice imaging mode divided into four sections each in concordance with the four excision margins of histography, and subsequently processed for conventional micrographic evaluation. RESULTS: A total of 80 HD-OCT images of 20 BCCs were evaluated and in 45% (9/20) HD-OCT correlated perfectly with the histography results. The sensitivity and specificity for the 80 evaluated HD-OCT images were 74% and 64% respectively. CONCLUSIONS: High-definition optical coherence tomography allows the postoperative identification of BCC in excised tissue ex vivo, but has still limitations in the recognition of tumour margins in comparison with the micrographic evaluation of frozen sections.