14 research outputs found

    Goodbye Hartmann trial: a prospective, international, multicenter, observational study on the current use of a surgical procedure developed a century ago

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    Background: Literature suggests colonic resection and primary anastomosis (RPA) instead of Hartmann's procedure (HP) for the treatment of left-sided colonic emergencies. We aim to evaluate the surgical options globally used to treat patients with acute left-sided colonic emergencies and the factors that leading to the choice of treatment, comparing HP and RPA. Methods: This is a prospective, international, multicenter, observational study registered on ClinicalTrials.gov. A total 1215 patients with left-sided colonic emergencies who required surgery were included from 204 centers during the period of March 1, 2020, to May 31, 2020. with a 1-year follow-up. Results: 564 patients (43.1%) were females. The mean age was 65.9 ± 15.6 years. HP was performed in 697 (57.3%) patients and RPA in 384 (31.6%) cases. Complicated acute diverticulitis was the most common cause of left-sided colonic emergencies (40.2%), followed by colorectal malignancy (36.6%). Severe complications (Clavien-Dindo ≥ 3b) were higher in the HP group (P < 0.001). 30-day mortality was higher in HP patients (13.7%), especially in case of bowel perforation and diffused peritonitis. 1-year follow-up showed no differences on ostomy reversal rate between HP and RPA. (P = 0.127). A backward likelihood logistic regression model showed that RPA was preferred in younger patients, having low ASA score (≤ 3), in case of large bowel obstruction, absence of colonic ischemia, longer time from admission to surgery, operating early at the day working hours, by a surgeon who performed more than 50 colorectal resections. Conclusions: After 100 years since the first Hartmann's procedure, HP remains the most common treatment for left-sided colorectal emergencies. Treatment's choice depends on patient characteristics, the time of surgery and the experience of the surgeon. RPA should be considered as the gold standard for surgery, with HP being an exception

    Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

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    : The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

    Physicochemical and Thermodynamic Characterization of the Encapsulation of Methyl Jasmonate by Natural and Modified Cyclodextrins Using Reversed-Phase High-Pressure Liquid Chromatography

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    Although the combinations of methyl jasmonate (MeJA) and cyclodextrins (CDs) have been used by different authors to stimulate the production of several metabolites, no study has been published about the possible formation of MeJA–CD complexes when these two molecules are added together to the reaction medium as elicitors. For this reason and because knowledge of the possible complexation process of MeJA with CD under different physicochemical conditions is essential if these two molecules are to be used in cell cultures, this paper looks at the complexation of MeJA with natural and modified CDs using a reversed-phase high-pressure liquid chromatography (RP-HPLC) system. The interaction of MeJA with β-CD was more efficient than with α- and γ-CDs. However, a modified CD, HP-β-CD, was the most effective of all of the CDs tested. Moreover, MeJA formed complexes with CD with a 1:1 stoichiometry, and the formation constants of these complexes were strongly dependent upon the temperature of the mobile phase used but not the pH. To obtain information about the mechanism of the affinity of MeJA for CD, the thermodynamic parameters Δ<i>G</i>°, Δ<i>H</i>°, and Δ<i>S</i>° were calculated. Finally, molecular modeling studies were carried out to propose which molecular interactions are established in the complexation process

    Water-Dependent Micromechanical and Rheological Properties of Silica Colloidal Crystals Studied by Nanoindentation

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    Here we show the suitability of nanoindentation to study in detail the micromechanical response of silica colloidal crystals (CCs). The sensitivity to displacements smaller than the submicrometer spheres size, even resolving discrete events and superficial features, revealed particulate features with analogies to atomic crystals. Significant robustness, long-range structural deformation, and large energy dissipation were found. Easily implemented temperature/rate-dependent nanoindentation quantified the paramount role of adsorbed water endowing silica CCs with properties of wet granular materials like viscoplasticity. A novel “nongranular” CC was fabricated by substituting capillary bridges with silica necks to directly test water-independent mechanical response. Silica CCs, as specific (nanometric, ordered) wet granular assemblies with well-defined configuration, may be useful model systems for granular science and capillary cohesion at the nanoscale

    Experimental Analysis and Numerical Modeling of a Shell and Tube Heat Storage Unit with Phase Change Materials

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    Thermal storages are part of highly integrated energy systems. The development of accurate and reduced models is critical for efficient simulations on a system-level and the analysis of the storage design, control, and integration. We present the experimental analysis and numerical modeling of a lab-scale shell and tube latent heat thermal energy storage (LHTES) unit with a (latent) storage capacity of about 10–15 kWh. The phase change material (PCM) is a high density polyethylene (HD-PE) with phase change temperatures between 120 and 135 °C. An efficient 2D numeric storage model is derived which accounts for design and material parameters of PCM, storage, and heat transfer fluid (HTF). Different probability distribution functions are used to model the PCM apparent specific heat capacity. From these functions the state of charge (SOC) can be predicted, which indicates the extent to which a LHTES is charged relative to storeable latent heat. Model predictions are fitted to experimental data from thermophysical measurements and from LHTES operation with partial and full charging/discharging. The storage model agrees well with experimental results. However, thermosphysical material analysis and storage operation indicated that the temperature range of phase transition is noticeable affected by storage loading operating condition, i.e., heating and cooling rates, which is not considered in the model. With this simplification it turns out that the model is limited by the quality of prediction of internal storage PCM temperatures

    Tamm Plasmon Resonance in Mesoporous Multilayers: Toward a Sensing Application

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    A novel optical sensor is proposed, based on the normal-incidence excitation of Tamm plasmons at the interface between a multilayer of porous SiO<sub>2</sub> and TiO<sub>2</sub>, acting as a permeable Bragg reflector, and a flat gold film. Transmittance spectra reveal a sharp Tamm mode within the stop-band of the distributed Bragg reflector, the spectral position of which was monitored upon exposure to various solvents, demonstrating the sensitivity of the device to changes of refractive index

    Centimeter-Scale Synthesis of Ultrathin Layered MoO<sub>3</sub> by van der Waals Epitaxy

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    We report on the large-scale synthesis of highly oriented ultrathin MoO<sub>3</sub> layers using a simple and low-cost atmospheric pressure, van der Waals epitaxy growth on muscovite mica substrates. By this method, we are able to synthesize high quality centimeter-scale MoO<sub>3</sub> crystals with thicknesses ranging from 1.4 nm (two layers) up to a few nanometers. The crystals can be easily transferred to an arbitrary substrate (such as SiO<sub>2</sub>) by a deterministic transfer method and be extensively characterized to demonstrate the high quality of the resulting crystal. We also study the electronic band structure of the material by density functional calculations. Interestingly, the calculations demonstrate that bulk MoO<sub>3</sub> has a rather weak electronic interlayer interaction, and thus, it presents a monolayer-like band structure. Finally, we demonstrate the potential of this synthesis method for optoelectronic applications by fabricating large-area field-effect devices (10 μm × 110 μm in lateral dimensions) and find responsivities of 30 mA W<sup>–1</sup> for a laser power density of 13 mW cm<sup>–2</sup> in the UV region of the spectrum and also as an electron acceptor in a MoS<sub>2</sub>-based field-effect transistor
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