Extraction of homogeneous lignin oligomers by ozonation of Miscanthus giganteus and vine shoots in a pilot scale reactor.

Lignin, a complex phenolic polymer crucial for plant structure, is mostly used as fuel but it can be harnessed for environmentally friendly applications. This article explores ozonation as a green method for lignin extraction from lignocellulosic biomass, aiming to uncover the benefits of the extracted lignin. A pilot-scale ozonation reactor was employed to extract lignin from Miscanthus giganteus (a grass variety) and vine shoots (a woody biomass). The study examined the lignin extraction and modification of the fractions and identified the generation of phenolic and organic acids. About 48 % of lignin was successfully extracted from both biomass types. Phenolic monomers were produced, vine shoots yielding fewer monomers than Miscanthus giganteus. Ozonation generated homogeneous lignin oligomers, although their molecular weight decreased during ozonation, with vine shoot oligomers exhibiting greater resistance to ozone. Extracted fractions were stable at 200 °C, despite the low molecular weight, outlining the potential of these phenolic fractions.

Fiebre aguda por mordedura de rata / Acute fever due to rats

La mordedura de rata puede transmitir diversos microorganismos, no obstante el desarrollo de medidas sanitarias y las mejores condiciones de habitabilidad de las viviendas han permitido que las enfermedades infecciosas transmitidas por agresiones de estos animales sean infrecuentes en los países industrializados. En circunstancias ocasionales este tipo de agresiones aún puede producirse, especialmente en zonas desfavorecidas de la periferia de grandes ciudades y en locales no habitados, siendo recomendable tener presente esta posibilidad. Se presenta un caso de fiebre por mordedura de rata en un paciente agredido mientras realizaba la limpieza de un local industrial. La evolución del cuadro fue típica, aislándose Streptobacillus moniliformis como agente causal, y el cuadro se controló sin presentar complicaciones con doxiciclina (AU)

[Acute fever due to rats]. / Fiebre aguda por mordedura de rata.

The bite of a rat can transmit diverse micro-organisms; however, the development of health measures and the improved conditions of habitability of homes have meant that the infectious diseases transmitted by the aggressions of these animals are infrequent in industrialised countries. In occasional circumstances this type of aggression can still take place, especially in depressed areas on the periphery of big cities and in uninhabited premises, this being a possibility that it is advisable to bear in mind. The case is presented of fever due to a rat bite in a patient who was attacked while cleaning an industrial premise. The evolution of the clinical picture was typical, with Streptobacillus moniliformis isolated as the causal agent, and the picture was controlled with doxicycline without complications arising.

ATR-FTIR sensor development for continuous on-line monitoring of chlorinated aliphatic hydrocarbons in a fixed-bed bioreactor.

This article describes the continuous on-line monitoring of a dechlorination process by a novel attenuated total reflection-Fourier transform infrared (ATR-FTIR) sensor. This optical sensor was developed to measure noninvasively part-per-million (ppm) concentrations of trichloroethylene (TCE), tetrachloroethylene (PCE), and carbon tetrachloride (CT) in the aqueous effluent of a fixed-bed dechlorinating bioreactor, without any prior sample preparation. The sensor was based on an ATR internal reflection element (IRE) coated with an extracting hydrophobic polymer, which prevented water molecules from interacting with the infrared (IR) radiation. The selective diffusion of chlorinated compound molecules from aqueous solution into the polymer made possible their detection by the IR beam. With the exclusion of water the detection limits were lowered, and measurements in the low ppm level became possible. The best extracting polymer was polyisobutylene (PIB) in the form of a 5.8-microm thick film, which afforded a detection limit of 2, 3, and 2. 5 mg/L (ppm) for TCE, PCE, and CT, respectively. Values of the enrichment factors between the polymer coating and the water matrix of these chloro-organics were determined experimentally and were compared individually with predictions obtained from the slopes of absorbance/concentration curves for the three analytes. Before coupling the ATR-FTIR sensor to the dechlorinating bioreactor, preliminary spectra of the chlorinated compounds were acquired on a laboratory scale configuration in stop-flow and flow-through closed-loop modes. In this way, it was possible to study the behavior and direct response of the optical sensor to any arbitrary concentration change of the analytes. Subsequently, the bioreactor was monitored with the infrared sensor coupled permanently to it. The sensor tracked the progression of the analytes' spectra over time without perturbing the dechlorinating process. To calibrate the ATR-FTIR sensor, a total of 13 standard mixtures of TCE, PCE and CT at concentrations ranging from 0 to 60 ppm were selected according to a closed symmetrical experimental design derived from a 3(2) full-factorial design. The above range of concentrations chosen for calibration reflected typical values during normal bioreactor operation. Several partial least squares (PLS) calibration models were generated to resolve overlapping absorption bands. The standard error of prediction (SEP) ranged between 0.6 and 1 ppm, with a relative standard error of prediction (RSEP) between 3 and 6% for the three analytes. The accuracy of this ATR-FTIR sensor was checked against gas chromatography (GC) measurements of the chlorocompounds in the bioreactor effluents. The results demonstrate the efficiency of this new sensor for routine continuous on-line monitoring of the dechlorinating bioreactor. This strategy is promising for bioprocess control and optimization.

Angiosarcomas radioinducidos / Radioinducted angiosarcomas

Se contribuye a la casuística con la presentación de 2 casos de angiosarcoma radioinducido, diagnosticados ambos, en pacientes de sexo femenino que previamente habían recibido dosis total de radioterapia, uno por presentar un linfoma tipo Hodgkin, y otro por carcinoma ductal de mama. En una de las pacientes el tiempo de latencia fue de 10 años, mientras que en la otra fue de 25 años. La evolución fue dispar, ya que mientras una tiene un año de evolución sin evidencias de enfermedad, la otra falleció debido a metástasis pulmonares y complicaciones cardíacas al año de ser operada

[Sweet's syndrome. Presentation of six cases and review of the literature]. / Síndrome de Sweet. Presentacíon de 6 casos y revisión de literatura.

The acute febrile neutrophilic dermatosis or Sweet syndrome, initially described in 1964 by Robert Sweet (1). It is characterized fever, neutrophilic leucocytosis, abrupt appearance of erythematous, painful, cutaneous plaquets and dense dermal infiltrate consisting of mature neutrophils without vasculitis sings. Malignancy has been described in the 10-15% of the reported cases. We report our series of 6 patients diagnosticated of this illness in our department. One of this patients has Sweet syndrome associated with a malignancy disorder. All of them had diagnostic criteria of the described disease and had good response to corticotherapy. We also report a bibliographic review of this infrequent syndrome.

[HELLP syndrome: case report and review of the literature]. / Síndrome de HELLP: a propósito de un caso y revisión de la literatura.

The case of a 32-years-old primipara in her thirty-second week of pregnancy who presented acute epigastric pain, citopenia, elevation in hepatic enzymes and analytical signs of hemolysis is presented. Ultrasonography demonstrated multiple hyperechogenic nodular images in the liver leading to a wide differential diagnosis. Liver biopsy findings, together with the mentioned clinico-biological alterations were indicative of the HELLP syndrome. Following caesarean, the patient presented rapid and total, symptomatic and analytical, improvement. Based on this case, a review of this entity in the literature and its prognostic implications and possible therapeutic approaches are reported.