RESUMEN
Experiments were conducted to determine the mechanisms of interaction with chromium of Aspergillus niger var tubingensis strain Ed8 in batch culture and in bioreactor experiments. Results obtained in this work showed that the interaction of A. niger var tubingensis Ed8 with Cr(VI) is based mainly in a reduction process and also, secondly, in a sorption process. Using electron microscopy techniques the ultrathin sections obtained from the mycelium biomass produced by the fungus in batch cultures showed the ability to incorporate Cr intracellulary, into low electron-dense inclusions, but not extracellularly. On the other hand, cultures without Cr(VI) of A. niger var tubingensis Ed8, grown in a bubble column bioreactor, reduced Cr(VI) immediately after repeated addition of this oxyanion; after six loads, 460 mg Cr(VI) was reduced to Cr(III) in 60 h, corresponding to a reduction rate of 2.62 mg Cr(VI)g(-1) dry biomass h(-1).
Asunto(s)
Aspergillus niger/efectos de los fármacos , Cromo/farmacología , Biomasa , Reactores Biológicos , Microscopía Electrónica de Transmisión , Espectrometría por Rayos XRESUMEN
A 51-year-old man with septic shock underwent three consecutive sessions of coupled plasma filtration-adsorption each lasting 12 hours. Sublingual microvascular perfusion was assessed using the orthogonal polarisation spectral imaging technique at three different times: immediate pre-coupled plasma filtration-adsorption phase, two hours following commencement and two hours after its termination. The video images of the sublingual microcirculation were analysed by an investigator blinded to the time of image acquisition. The De Backer's score was calculated. During the coupled plasma filtration-adsorption, the number of perfused vessels increased compared with the pre-coupled plasma filtration-adsorption period, but decreased again after its termination. It is arguable that the elimination of septic mediators during the procedure could account for the observed variations.
Asunto(s)
Microcirculación/fisiología , Plasma , Choque Séptico/fisiopatología , Choque Séptico/terapia , Lesión Renal Aguda/fisiopatología , Adsorción , Endotelio Vascular/fisiología , Fascitis Necrotizante/complicaciones , Fibrinolíticos/administración & dosificación , Fibrinolíticos/uso terapéutico , Filtración , Hemodinámica/efectos de los fármacos , Heparina/administración & dosificación , Heparina/uso terapéutico , Humanos , Inflamación/etiología , Inflamación/prevención & control , Masculino , Persona de Mediana Edad , Suelo de la Boca/irrigación sanguínea , Flujo Sanguíneo Regional/fisiología , Extremidad Superior , Grabación en VideoRESUMEN
Fungal peroxidases and phenoloxidases are widely used in aromatic toxic compounds degradation. Peroxidases, such as lignin peroxidase and manganese peroxidase, as well as laccases are mainly produced by basidiomycetes and to a lower extent by other fungi, such as ascomycetes. Peroxidase-encoding genes have been described and homologous expression has been achieved in basidiomycetes. Heterologous expression has also been achieved in some non-producing peroxidase ascomycetes, like Penicillium and Aspergillus. In this work, heterologous expression of peroxidase-encoding genes, lignin peroxidase, and manganese peroxidase was achieved in a zygomycete producing only phenoloxidases (Amylomyces rouxii), aimed at coupling two different pathways used in nature for PCP removal in only one microbial strain. The ability of PCP removal was assayed with one of the obtained transformants, resulting in increased activity with respect to the ability of the parental strain cultured free of the inducer tyrosine (95% and 45%, respectively, of the initial PCP (12.5 mg L(-1)) in 120 h, or 100% and 49%, respectively, of the initial PCP after 144 h of liquid culture).
Asunto(s)
Contaminantes Ambientales/metabolismo , Mucorales/enzimología , Pentaclorofenol/metabolismo , Peroxidasas/metabolismo , Phanerochaete/enzimología , Biodegradación Ambiental , Biomasa , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Cinética , Redes y Vías Metabólicas , Mucorales/genética , Peroxidasas/genéticaRESUMEN
AIMS: To investigate the effect of pH regulation and nutrient concentration on cephalosporin C (CPC) production in solid-state fermentation (SSF), using sugarcane bagasse as inert support, impregnated with liquid medium. METHODS AND RESULTS: Solid-state fermentation using different initial pH values, buffer and nutrient concentrations were performed. Results revealed pH as a key parameter in CPC SSF, as it hampered the antibiotic production not only above 7.8, but also under 6.4. Using initial pH lower than 6.8 and PB in the solid medium, it was possible to keep pH within the production range, increase the production period (from 1 to 3 days) and hence the CPC yield from 468 to 3200 microg gdm(-1) (g(-1) of dry matter). CONCLUSION: Parameters that help to keep pH in adequate values for CPC production in SSF, such as initial pH, buffering system and nutrient concentration, can greatly increase the production time and CPC yields in this fermentation technique. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first work on CPC production on impregnated support, and the only one revealing pH as a key parameter; it is also shown that high nutrient concentration can improve CPC yields in SSF as long as pH is kept under control.
Asunto(s)
Acremonium/metabolismo , Cefalosporinas/metabolismo , Fermentación , Acremonium/efectos de los fármacos , Acremonium/crecimiento & desarrollo , Medios de Cultivo/farmacología , Concentración de Iones de HidrógenoRESUMEN
Amylomyces rouxii eliminated 85% of initial pentachlorophenol (PCP) at 12.5 mg l(-1) when grown with 0.1 g tyrosine l(-1), but only 55% without tyrosine. Addition of tyrosine in the culture medium increased the monophenolase activity by 1.8-fold. Tyrosinase is thus indicated to be the phenoloxidase involved in PCP degradation by A. rouxii .
Asunto(s)
Proteínas Fúngicas/química , Hongos/enzimología , Monofenol Monooxigenasa/química , Pentaclorofenol/química , Biodegradación AmbientalRESUMEN
Three series of 5-day submerged cultures with Pediococcus pentosaceus MITJ-10 and Lactobacillus acidophilus Hansen 1748 were carried out in starch-based media, and the effect of cultural factors on the changes of starch, diacetyl and amylase activity determined. In axenic cultures, Ped. pentosaceus MITJ-10 produced more diacetyl (63.27 mg l(-1)) by adding glucose, yeast extract and CaCO3 (P < 0.01), at 28 degrees C (P < 0.05); but more starch was consumed (18.4 g l(-1)) in the absence of glucose (P < 0.01). Lact. acidophilus Hansen 1748 consumed more starch (26.56 g l(-1)) at 28 degrees C, with CaCO3, glucose (P < 0.01) and yeast extract (P < 0.05); however, the amylolytic activity (10077U l(-1)) was favoured at 35 degrees C (P < 0.01). Little starch was consumed in mixed cultures due to the low pH; nevertheless, diacetyl content rose to 135.76 mg l(-1) at 32 degrees C (P < 0.01). Therefore, both studied strains might be useful to produce aromatic extensors from starchy substrates. These natural aromatic extensors are of interest to the food industry.
Asunto(s)
Diacetil/metabolismo , Lactobacillus acidophilus/crecimiento & desarrollo , Pediococcus/crecimiento & desarrollo , Almidón/metabolismo , Amilasas/metabolismo , Técnicas Bacteriológicas , Carbonato de Calcio/farmacología , Cromatografía de Gases , Medios de Cultivo , Lactobacillus acidophilus/metabolismo , Pediococcus/metabolismo , TemperaturaRESUMEN
Despite the wide number of diseases currently or previously treated with plasma exchange and plasmapheresis, the clinical effectiveness of these treatments has been established by large, controlled clinical trials only in few clinical conditions. The firmly accepted and the possible indications for these techniques in critically ill patients are reviewed and discussed, as well as their complications and possible side effects.
Asunto(s)
Cuidados Críticos , Plasmaféresis/métodos , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/terapia , Ensayos Clínicos Controlados como Asunto , Enfermedad Crítica , Humanos , Enfermedades del Sistema Inmune/terapia , Insuficiencia Multiorgánica/terapia , Miastenia Gravis/terapia , Intercambio Plasmático/efectos adversos , Intercambio Plasmático/métodos , Plasmaféresis/efectos adversos , Polirradiculoneuropatía/terapia , Púrpura Trombocitopénica Trombótica/terapia , Síndrome de Respuesta Inflamatoria Sistémica/terapiaRESUMEN
Mediastinitis is a life-threatening complication of cardiac, neck and oesophageal surgery. It has also been reported following upper digestive and respiratory procedures and as a consequence of oesophageal perforation following the ingestion of foreign bodies. Much more infrequently, mediastinitis can occur in association with oropharyngeal or cervical infections. We describe the case of a patient with fatal mediastinitis and septic shock. The onset of mediastinitis was preceded by a 2-day course of sore throat and other flu-like symptoms.
Asunto(s)
Mediastinitis/microbiología , Faringitis/microbiología , Infecciones Estreptocócicas/microbiología , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Resultado Fatal , Femenino , Humanos , Mediastinitis/diagnóstico por imagen , Insuficiencia Multiorgánica/microbiología , Choque Séptico/microbiología , Infecciones Estreptocócicas/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
To evaluate the symptoms, the associated lesions, the treatment and the outcome of patients with blunt carotid injury (BCI), we reviewed the records of all patients admitted to our intensive care unit with head trauma between May 1991 and May 1995. A patient's assessment included the commonly used severity scores and cranial computed tomography (CT). Other diagnostic investigations were performed according to the clinical setting. Four patients (2 males, 2 females, age 29 +/- 13 years) out of 145 were diagnosed to have BCI. At admission, the Glasgow Coma Scale (GCS) was > or = 12 in all patients, and was associated with hemiparesis in three of them; the fourth became paretic 48 hours later. No pathological elements were demonstrated at the initial CT scan, whilst subsequent examinations showed signs of ischaemia after a variable interval from admission. In every patient the radiologic investigations demonstrated a thrombotic obstruction of the internal carotid artery (ICA), associated with an intimal dissection in two cases. Three patients were discharged with only minor neurologic symptoms. The fourth patient was referred to our ICU after the development of a massive hemispheric infarction, and died 3 days after admission.
Asunto(s)
Traumatismos de las Arterias Carótidas , Heridas no Penetrantes/diagnóstico por imagen , Adolescente , Adulto , Angiografía de Substracción Digital , Resultado Fatal , Femenino , Escala de Coma de Glasgow , Hemiplejía/etiología , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Evaluación de Resultado en la Atención de Salud , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/complicaciones , Heridas no Penetrantes/terapiaRESUMEN
The case of posttraumatic patient with persistent vegetative state and severe and prolonged hyperthermia (T = 39-40 degrees C for more than 20 days), in absence of infection, is described. Diffuse muscular rigidity, treated with L-dopa, slightly preceded the onset of hyperthermia, which was treated with several antipyretics, including phenotiazines. The withdrawal of these drugs and the administration of dantrolene and bromocriptine was followed by the restoration of the normal body temperature.
Asunto(s)
Temperatura Corporal/efectos de los fármacos , Fiebre/inducido químicamente , Levodopa/efectos adversos , Adulto , Bromocriptina/efectos adversos , Estudios de Seguimiento , Humanos , Masculino , Factores de TiempoRESUMEN
The authors reports the case of a patient with quadriplegia associated with respiratory failure. A few days before, a paralysis of the oculomotor nerves appeared, which rapidly spreads in cranio-caudal fashion. The occurrence of a similar symptomatology in a patients' relative addressed the diagnosis toward a possible Clostridium botulinum intoxication. Other possible differential diagnoses are reviewed and discussed.
Asunto(s)
Botulismo , Botulismo/complicaciones , Botulismo/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oftalmoplejía/diagnóstico , Oftalmoplejía/etiologíaRESUMEN
The authors report the case of a patient who developed irreversible cardiovascular collapse during a laparoscopic cholecystectomy. The abrupt onset of shock and the rapid deterioration of the hemodynamic conditions prevented a thorough diagnostic workup. Possible differential diagnoses of hypotension occurring during laparoscopic procedures are reviewed and discussed.