RESUMEN
Herein, a quadruple biomagnetic nanocomposite of cross-linked chitosan-ethylene glycol diglycidyl ether/organo-nanoclay (MCH-EGDE/ORNC) was designed for the uptake of remazol brilliant blue R (RBBR) dye from aqueous environment. The adsorption process was systematically improved via the Box-Behnken design (BBD) to determine the influence of key uptake parameters, including MCH-EGDE/ORNC dosage, pH, and time, on the RBBR removal. The highest RBBR removal of 87.5 % was achieved at the following conditions: MCH-EGDE/ORNC dosage: 0.1 g/100 mL; pH: 4.0; contact time: 25 min. The findings of the kinetics and equilibrium studies revealed an excellent fit to the pseudo-second order and the Freundlich models, respectively. The adsorption capacity of the MCH-EGDE/ORNC for RBBR was found to be 168.4 mg/g, showcasing its remarkable adsorption capability. The present work highlights the potential of MCH-EGDE/ORNC biomaterial as an advanced adsorbent and lays the foundation for future applications in water purification and environmental remediation.
Asunto(s)
Quitosano , Nanocompuestos , Compuestos Azo , Concentración de Iones de HidrógenoRESUMEN
In order to assess the impact of nanoplastics on marine species, polystyrene nanoparticles (PS NPs) have been largely used as model particles. Here we studied the effects of 50 nm amino-modified PS-NH2 on Mediterranean sea urchin Paracentrotus lividus immune system cells (coelomocytes) in the presence of celomic fluid (CF) and at different NP concentrations (1, 5, 10, and 25 µg mL-1) and experimental conditions (absence or presence of EDTA). PS-NH2 acquired a protein corona once incubated with CF, dominated by the toposome precursor protein (TPP). In short-term cultures, a significant concentration- and time-dependent decrease in lysosomal membrane stability and apoptotic-like nuclear alterations were observed in phagocytes upon exposure to PS-NH2 (10 and 25 µg mL-1) in CF but they resulted abolished in the presence of EDTA confirming the role of TPP in triggering PS-NH2-coelomocytes interaction and toxicity. PS-NH2 did not alter MXR phenotype but the observed dose-dependent decrease in calcein accumulation suggests the ability of PS-NH2 to affect pump's efflux activity. Overall results encourage additional studies on positively charged nanoplastics, since the observed effects on sea urchin coelomocytes as well as the TPP corona formation might represent a first step for addressing their impact on sensitive marine species.
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Nanopartículas/toxicidad , Paracentrotus/efectos de los fármacos , Poliestirenos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Cationes , Nanopartículas/química , Paracentrotus/inmunología , Poliestirenos/química , Contaminantes Químicos del Agua/químicaRESUMEN
We investigated the association between environmental exposure to radiofrequency electromagnetic fields (RF-EMF) and risk of lymphoma subtypes in a case-control study comprised of 322 patients and 444 individuals serving as controls in Sardinia, Italy in 1998-2004. Questionnaire information included the self-reported distance of the three longest held residential addresses from fixed radio-television transmitters and mobile phone base stations. We georeferenced the residential addresses of all study subjects and obtained the spatial coordinates of mobile phone base stations. For each address within a 500-meter radius from a mobile phone base station, we estimated the RF-EMF intensity using predictions from spatial models, and we performed RF-EMF measurements at the door in the subset of the longest held addresses within a 250-meter radius. We calculated risk of lymphoma and its major subtypes associated with the RF-EMF exposure metrics with unconditional logistic regression, adjusting by age, gender and years of education. In the analysis of self-reported data, risk associated with residence in proximity (within 50 meters) to fixed radio-television transmitters was likewise elevated for lymphoma overall [odds ratio = 2.7, 95% confidence interval = 1.5-4.6], and for the major lymphoma subtypes. With reference to mobile phone base stations, we did not observe an association with either the self-reported, or the geocoded distance from mobile phone base stations. RF-EMF measurements did not vary by case-control status. By comparing the self-reports to the geocoded data, we discovered that the cases tended to underestimate the distance from mobile phone base stations differentially from the controls ( P = 0.073). The interpretation of our findings is compromised by the limited study size, particularly in the analysis of the individual lymphoma subtypes, and the unavailability of the spatial coordinates of radio-television transmitters. Nonetheless, our results do not support the hypothesis of a link between environmental exposure to RF-EMF from mobile phone base stations and risk of lymphoma subtypes.
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Campos Electromagnéticos/efectos adversos , Linfoma/etiología , Neoplasias Inducidas por Radiación/etiología , Exposición a la Radiación/efectos adversos , Ondas de Radio/efectos adversos , Adulto , Anciano , Estudios de Casos y Controles , Teléfono Celular , Femenino , Humanos , Linfoma/epidemiología , Masculino , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/epidemiología , Medición de RiesgoRESUMEN
Dried herbal preparations, based on "Zornia latifolia," are commonly sold on web, mainly for their supposed hallucinogenic properties. In this work, we demonstrate that these commercial products contain a different Fabacea, i.e., Stylosanthes guianensis, a cheaper plant, widely cultivated in tropical regions as a fodder legume. We were provided with plant samples of true Zornia latifolia from Brazil, and carried out a thorough comparison of the two species. The assignment of commercial samples was performed by means of micro-morphological analysis, DNA barcoding, and partial phytochemical investigation. We observed that Z. latifolia contains large amounts of flavonoid di-glycosides derived from luteolin, apigenin, and genistein, while in S. guianensis lesser amounts of flavonoids, mainly derived from quercetin, were found. It is likely that the spasmolytic and anxiolytic properties of Z. latifolia, as reported in traditional medicine, derive from its contents in apigenin and/or genistein.
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Contaminación de Medicamentos , Fabaceae/química , Flavonoides/análisis , Extractos Vegetales/análisis , Apigenina , Brasil , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Luteolina , Plantas , QuercetinaRESUMEN
Creatine, a compound that is critical for energy metabolism of nervous cells, crosses the blood-brain barrier (BBB) and the neuronal plasma membrane with difficulty, and only using its specific transporter. In the hereditary condition where the creatine transporter is defective (creatine transporter deficiency) there is no creatine in the brain, and administration of creatine is useless lacking the transporter. The disease is severe and incurable. Creatine-derived molecules that could cross BBB and plasma membrane independently of the transporter might be useful to cure this condition. Moreover, such molecules could be useful also in stroke and other brain ischemic conditions. In this paper, we investigated three creatine salts, creatine ascorbate, creatine gluconate and creatine glucose. Of these, creatine glucose was ineffective after transporter block with guanidine acetic acid (GPA) administration. Creatine ascorbate was not superior to creatine in increasing tissue creatine and phosphocreatine content after transporter impairment, however even after such impairment it delayed synaptic failure during anoxia. Finally, creatine gluconate was superior to creatine in increasing tissue content of creatine after transporter block and slowed down PS disappearance during anoxia, an effect that creatine did not have. These findings suggest that coupling creatine to molecules having a specific transporter may be a useful strategy in creatine transporter deficiency. In particular, creatine ascorbate has effects comparable to those of creatine in normal conditions, while being superior to it under conditions of missing or impaired creatine transporter.
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Ácido Ascórbico/farmacología , Creatina/farmacología , Gluconatos/farmacología , Glucosa/farmacología , Fármacos Neuroprotectores/farmacología , Animales , Ácido Ascórbico/química , Creatina/química , Evaluación Preclínica de Medicamentos , Potenciales Evocados/efectos de los fármacos , Potenciales Evocados/fisiología , Gluconatos/química , Glucosa/química , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipoxia Encefálica/tratamiento farmacológico , Hipoxia Encefálica/metabolismo , Masculino , Proteínas de Transporte de Membrana/metabolismo , Ratones Endogámicos ICR , Estructura Molecular , Fármacos Neuroprotectores/química , Técnicas de Cultivo de TejidosRESUMEN
Cannabinoids, endogenous and exogenously administered, are known to positively regulate food intake and energy balance. Since CB1 receptor antagonists reduce food intake and antagonize overweight, we developed a new CB1 receptor antagonist in an attempt to identify a compound with potential application in overeating disorders. The newly developed SM-11 compound dose-dependently decreases food intake in rats by 15-20%. Moreover, SM-11 reduces self-administration of palatable food in both food restricted and ad libitum fed rats, suggesting an action on the hedonic component of food intake. Thus, we next tested the effect of SM-11 on the stimulating properties of the CB1 receptor agonist WIN55,212-2 (WIN) on the electrophysiological activity of Nucleus Accumbens-projecting dopaminergic neurons of the ventral tegmental area (VTA). SM-11 fully and readily antagonized the WIN-induced increments in single spiking and burst firing of antidromically-identified dopamine neurons. When administered to naïve (no WIN-pretreated) rats, SM-11 did not alter basal neuronal activity, thereby suggesting a pure antagonistic profile. SM-11 thus appears as a promising candidate in the search of potential anti-obesity medications.
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Antagonistas de Receptores de Cannabinoides/farmacología , Dopamina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Animales , Benzoxazinas/farmacología , Cannabinoides/farmacología , Neuronas Dopaminérgicas/metabolismo , Masculino , Morfolinas/farmacología , Naftalenos/farmacología , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor Cannabinoide CB1/metabolismo , Área Tegmental Ventral/efectos de los fármacos , Área Tegmental Ventral/metabolismoRESUMEN
Brainstem dysfunctions are associated to high risk of developing severe disability in patients with multiple sclerosis (PwMS), often undetected by conventional routine assessments. In this view, the purpose of this study was to monitor brainstem function over a short-term period in PwMS, comparing clinical and magnetic resonance imaging (MRI) examinations with evoked potentials (EPs) and brainstem reflexes (BSRs). Forty-five PwMS were evaluated at baseline and after 15.1 ± 4.2 months through Expanded Disability Status Scale (EDSS) score, MRI, EPs, vestibulo-masseteric (VMR), acoustic-masseteric (AMR), vestibulo-collic (VCR) and trigemino-collic (TCR) reflexes. At baseline, brainstem alterations were detected by EDSS, MRI, EPs and BSRs in 40, 77.8, 84.4 and 82.2 % of patients, respectively. At follow-up, EDSS and MRI remained unchanged, while EP and BSR deteriorated in 86.7 and 91.1 % of patients, respectively. Changes from 1 to 3 altered EPs and from 1 to 4 altered BSRs were significant only for EPs (p = 0.028). The analysis of grading severity for each test disclosed significant worsening of the VMR, AMR, TCR and P14 wave of the median somatosensory EP. Combined EP/BSR recordings were significantly more sensitive than paired EDSS/MRI assessments at baseline (93.3 versus 80 %; p = 0.006) and follow-up (97.8 versus 82.2 %; p = 0.008). In the short-term VMR, AMR, TCR and P14 wave disclosed a significant functional brainstem deterioration by detecting lesions that remained clinically and MRI silent. Our findings provide evidence for a valuable role of neurophysiological methods, especially BSRs, in investigating and monitoring brainstem dysfunctions in MS, in comparison with the standard clinical and MRI procedures.
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Tronco Encefálico/fisiopatología , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/patología , Reflejo/fisiología , Estimulación Acústica , Adulto , Alcaloides , Tronco Encefálico/diagnóstico por imagen , Evaluación de la Discapacidad , Estimulación Eléctrica , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Estadística como Asunto , Adulto JovenRESUMEN
Anorexia-cachexia associated with cancer and other diseases is a common and often fatal condition representing a large area of unmet medical need. It occurs most commonly in advanced cancer and is probably a consequence of molecules released by tumour cells, or tumour-associated interstitial or immune cells. These may then act directly on muscle to cause atrophy and/or may cause anorexia, which then leads to loss of both fat and lean mass. Although the aetiological triggers for this syndrome are not well characterized, recent data suggest that MIC-1/GDF15, a transforming growth factor-beta superfamily cytokine produced in large amounts by cancer cells and as a part of other disease processes, may be an important trigger. This cytokine acts on feeding centres in the hypothalamus and brainstem to cause anorexia leading to loss of lean and fat mass and eventually cachexia. In animal studies, the circulating concentrations of MIC-1/GDF15 required to cause this syndrome are similar to those seen in patients with advanced cancer, and at least some epidemiological studies support an association between MIC-1/GDF15 serum levels and measures of nutrition. This article will discuss its mechanisms of central appetite regulation, and the available data linking this action to anorexia-cachexia syndromes that suggest it is a potential target for therapy of cancer anorexia-cachexia and conversely may also be useful for the treatment of severe obesity.
Asunto(s)
Anorexia/etiología , Caquexia/etiología , Factor 15 de Diferenciación de Crecimiento/metabolismo , Terapia Molecular Dirigida , Neoplasias/complicaciones , Obesidad/complicaciones , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Anorexia/psicología , Anorexia/terapia , Apetito/efectos de los fármacos , Apetito/genética , Biomarcadores/metabolismo , Caquexia/psicología , Caquexia/terapia , Metabolismo Energético/efectos de los fármacos , Metabolismo Energético/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Factor 15 de Diferenciación de Crecimiento/efectos de los fármacos , Humanos , Terapia Molecular Dirigida/tendencias , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/psicología , Obesidad/genética , Obesidad/metabolismo , Obesidad/psicología , Factor de Crecimiento Transformador beta1/efectos de los fármacos , Aumento de Peso/efectos de los fármacosRESUMEN
Creatine, an ergogenic compound essential for brain function, is very hydrophilic and needs a transporter to cross lipid-rich cells' plasma membranes. Hereditary creatine transporter deficiency is a severe incurable neurological disease where creatine is missing from the brain. Creatine esters are more lipophylic than creatine and may not need the transporter to cross plasma membranes. Thus, they may represent a useful therapy for hereditary creatine transporter deficiency. Creatine ethyl ester (CEE) is commercially available and widely used as a nutritional supplement. It was reported that it enters the cells of patients lacking the transporter but was not useful when administered in vivo, by oral route, to affected patients. In this paper we investigated the effects of CEE in in vitro brain slices before and after biochemical block of the creatine transporter. We found that CEE is rapidly degraded in the aqueous incubation medium to creatinine, however it remains in solution long enough to cause an increase in tissue content of creatine and, more prominently, phosphocreatine. Both CEE and creatine delayed the anoxia-induced failure of synaptic transmission, and there was no difference between the two compounds. Contrary to what we expected, CEE did not increase tissue creatine content after the creatine transporter was blocked. We confirm that CEE is probably not an effective treatment for hereditary creatine transporter deficiency. Two factors seem to affect the possibility for creatine esters to be exploited in the therapy of creatine transporter deficiency. First, the size of their alcohol moiety should be increased since this would increase the lipophilicity of the compound and improve its ability to diffuse through biological membranes. Second, creatine esters should be further modified to slow their degradation to creatinine and increase their half-life in aqueous solutions. Moreover, we should not forget the possibility that they are degraded in vivo by plasma esterases.
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Creatina/análogos & derivados , Hipocampo/metabolismo , Proteínas de Transporte de Membrana/deficiencia , Animales , Cromatografía Líquida de Alta Presión , Creatina/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Técnicas de Cultivo de Órganos , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
A modified Poisson-Boltzmann analysis is made of the double layer interaction between two silica surfaces and two alumina surfaces in chloride electrolyte. The analysis incorporates nonelectrostatic ion-surface dispersion interactions based on ab initio ionic excess polarizabilities with finite ion sizes. A hydration model for the tightly held hydration shell of kosmotropic ions is introduced. A direct Hofmeister series (K > Na > Li) is found at the silica surface while the reversed series (Li > Na > K) is found at alumina, bringing theory in line with experiment for the first time. Calculations with unhydrated ions also suggest that surface-induced dehydration may be occurring at the alumina surface.
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Metales Alcalinos/química , Agua/química , Óxido de Aluminio/química , Cloruros/química , Electrólitos/química , Concentración de Iones de Hidrógeno , Sales (Química)/química , Dióxido de Silicio/química , Electricidad Estática , Propiedades de SuperficieRESUMEN
We constructed a single-chain variable fragment miniantibody (G11-scFv) directed toward the transactivation domain of c-Myc, which is fused with the internalization domain Int of Antennapedia at its carboxyl terminus (a cargo-carrier construct). In ELISA experiments, an EC(50) for binding saturation was achieved at concentrations of G11-scFv-Int(-) of approximately 10(-8) M. Internalization of a fluoresceinated Fl-G11-scFv-Int(+) construct was observed in intact human cultured cells with confocal microscopy. After 5 h of incubation in medium containing 1 microM Fl-G11-scFv-Int(+) or Fl-G11-scFv-Int(-), fluorescence intensity was determined in individual cells, both for cytoplasmic and nuclear compartments: concentration levels of Fl-G11-scFv-Int(+), relative to the extracellular culture medium concentration, were 4-5 times higher in the cytoplasm, 7-8 times higher in the nucleus, and 10 times higher in the nucleoli. In the same experimental conditions, the Fl-G11-scFv-Int(-) construct was 3-4 times more concentrated outside of the cells than inside. Cell membranes kept their integrity after 5 h of incubation. The antiproliferative activity of our miniantibody was studied on HCT116 cells. Incubation with 4 microM G11-scFv-Int(+) for 4 days induced very significant statistical and biological growth inhibition, whereas Int alone was completely inactive. Miniantibodies capable of penetrating cell membranes dramatically broaden the potential for innovative therapeutic agents and attack of new targets.
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Proteína con Homeodominio Antennapedia/química , Anticuerpos Monoclonales/metabolismo , Región Variable de Inmunoglobulina/metabolismo , Proteínas Proto-Oncogénicas c-myc/antagonistas & inhibidores , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Núcleo Celular/metabolismo , Células HCT116 , Humanos , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Estructura Terciaria de Proteína , Proteínas Proto-Oncogénicas c-myc/inmunología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
PURPOSE: This article discusses the possible pathophysiological conditions responsible for magnetic resonance imaging (MRI) finding of transient focal lesions in the splenium of the corpus callosum on the basis of our experience and a review of the literature. MATERIALS AND METHODS: In six patients undergoing computed tomography (CT) and MRI examinations, focal nonhemorrhagic lesions of the splenium of the corpus callosum were incidentally discovered. Patients had been referred for suspected encephalitis (n=2), dural sinus thrombosis (n=1) and multiple sclerosis (n=3). MRI examinations were repeated after 4, 8 and 12 weeks and in two cases also after 6 and 9 months. MRI and medical records were retrospectively reviewed with respect to patients' clinical history, medication and laboratory findings to define lesion aetiology. RESULTS: In all patients, the lesions were isolated, reversible and with no contrast enhancement. In four patients, the lesion disappeared after complete remission of the underlying disease, whereas in two patients, they persisted for 6 and 9 months, respectively. CONCLUSIONS: To our knowledge and according to previous reports, the fact that these lesions are detected in a relatively large number of conditions with heterogeneous etiopathogenetic factors leads to the hypothesis that a common underlying pathophysiological mechanism that, considering signal characteristic, reversibility and white matter location, could be represented by vasogenic oedema.
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Encefalopatías/patología , Cuerpo Calloso/patología , Imagen por Resonancia Magnética , Adolescente , Adulto , Femenino , Humanos , MasculinoRESUMEN
Peptides corresponding to three alpha helices present in the C-terminal region of the human prion protein have been synthesized and their structural autonomy analyzed by circular dichroism (CD) and NMR spectroscopy. The results obtained indicate that the protein fragment corresponding to the alpha 3-helix, in contrast to alpha 1 and alpha 2 peptides, shows a complete structural autonomy. The chemical shifts values found for NH and CHalpha resonance of the isolated alpha 3 peptide, formed by 30 aminoacid residues, were markedly and surprisingly similar to the corresponding values of the alpha 3-helix in the protein. The structural autonomy of the alpha 3-helix is profoundly determined by the presence of the conserved capping box and, in part, by the ionic bond formed between Glu200 and Lys204. On the basis of these observations a novel PrP consensus pattern, centered on the alpha 3-helix region, has been defined. The data indicate that this autonomous and highly conserved region of the PrPc likely plays a critical role in folding and stability. This gives an explanation of why many of pathogenic mutations occur in this part of the molecule, sharing relevant effects on the overall protein conformation. In particular the D202N capping mutation almost completely destabilizes the isolated alpha 3 peptide. While it is well known that the D202N substitution is associated with a GSS disease, the possible structural basis of this fatal pathology has never been investigated. We propose that a lower alpha 3-helical propensity leading to a major destabilization of the PrPc molecule initiates the pathogenic process associated with D202N capping mutation.
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Mutación/fisiología , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Priones/genética , Priones/metabolismo , Secuencia de Aminoácidos , Animales , Dicroismo Circular , Humanos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Molecular , Datos de Secuencia Molecular , Fragmentos de Péptidos/síntesis química , Priones/síntesis química , Conformación ProteicaRESUMEN
Studies of the oxidation of beta-nicotinamide adenine dinucleotide (NADH) at glassy carbon (GCEs) electrode surfaces, modified with nonconventional conducting polymer nanotubules, are reported. In contrast to the situation with conventional carbon electrodes, chemical reversibility of the NADH oxidation reaction was achieved by means of poly(1,2-diaminobenzene) conducting nanotubule coatings. A Delta E(p) of 425 mV (vs Ag/AgCl; pH 7.0) was observed. The NADH amperometric response of the conducting nanotubule modified GCEs was shown to be extremely stable, with 98% of the initial response remaining after 48 h of stirring in the presence of 1 x 10(-4) M NADH solutions (compared to 14% at the poly(1,2-diaminobenzene) modified GCEs). The nonconventional conducting polymer nanotubule-coated electrodes, when tested in amperometric mode for NADH electrochemical oxidation at an applied potential of 450 mV, showed a sensitivity of 99 nA/mM, an operational stability for 2 days, a storage stability of 2 weeks at 4 degrees C, a linearity from 5 x 10(-5) to 1 x 10(-3) M, and good NADH chemical reversibility, all of which make them useful tools for dehydrogenase enzyme probe assembly.
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Técnicas Biosensibles , Carbono/química , Electrodos , NAD/análisis , Nanotubos/química , Polímeros/química , ElectroquímicaRESUMEN
PURPOSE: To test the effect of temporary caval filtration on pulmonary emboli when a mechanical thrombolytic device is used to treat venous thrombosis and to test the effects of a modified device on caval patency at 30-day follow-up. MATERIALS AND METHODS: In a canine model of iliocaval subacute thrombosis, mechanical thrombolysis was performed with use of an 8-F over-the-wire Arrow-Trerotola Percutaneous Thrombolytic Device (PTD) with a 9-mm (iliac) or 15-mm (inferior vena cava [IVC]) basket. In six procedures, the device was made of nitinol monofilament, and in another six, it was made of braided stainless steel. All procedures were performed with a nitinol expandable sheath (temporary filter) in the suprarenal IVC. Low-molecular-weight heparin was given daily after the procedure. Venography, pulmonary arteriography, measurement of blood gases, and pulmonary artery (PA) pressure measurement were performed before and after the procedure and at 30-day follow-up. Pulmonary arteriograms from the group treated with stainless-steel devices were compared to those from an earlier group of animals in which the identical procedure was performed without caval filtration. The IVC was examined histologically. RESULTS: Thrombolysis was successful in all animals. Rare segmental and subsegmental pulmonary emboli (PE) were seen arteriographically; compared to procedures without filters, there was a significant reduction in PE (P <.002). However, a mild increase in pulmonary artery pressure, decrease in pH, and increase in pCO(2) were observed postprocedurally. At 30-day follow-up (n = 11), IVC patency was preserved in 45% (n = 5) of animals overall. Caval patency was significantly better in animals in which the combination of stainless-steel devices was used (five of six = 83% vs zero with nitinol device; P =.015). Histologically, the stainless-steel device caused little intimal injury and fibrosis-less than that seen with the nitinol device. CONCLUSIONS: Temporary filtration reduces, but does not completely eliminate, PE during mechanical thrombolysis. The stainless-steel device results in less intimal injury and better caval patency than the nitinol device.
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Filtros de Vena Cava , Trombosis de la Vena/terapia , Animales , Análisis de los Gases de la Sangre , Modelos Animales de Enfermedad , Perros , Diseño de Equipo , Estudios de Seguimiento , Embolia Pulmonar/prevención & control , Radiografía , Vena Cava Inferior/patología , Trombosis de la Vena/diagnóstico por imagenRESUMEN
RATIONALE AND OBJECTIVES: The authors performed this study to evaluate the mortality and morbidity associated with a simple technique for inducing diabetes in dogs--suprarenal intraarterial infusion of alloxan and streptozotocin during balloon occlusion of the juxtarenal abdominal aorta. MATERIALS AND METHODS: The authors attempted to induce diabetes in six purpose-bred dogs. After the dogs were fasted for 12 hours, the abdominal aorta at the level of the origin of the renal arteries was occluded with an angioplasty balloon introduced by means of a femoral approach. A 3-F microcatheter (n = 1) or infusion wire (n = 5) was introduced via the percutaneous transluminal angioplasty catheter and positioned at the level of the celiac axis, and a mixture of streptozotocin (20-25 mg/kg) and alloxan (20-25 mg/kg) was infused. Diabetes was considered to have been induced if the dogs experienced sustained hyperglycemia. RESULTS: There were no deaths during the follow-up period (range, 7 months to 2 1/2 years). A diabetes-like state was induced in five of the six dogs, and no nephrotoxicity was seen. Diabetes was not induced in one dog owing to caudal migration of an undersized balloon during the infusion; this also resulted in reversible renal damage. CONCLUSION: This simple technique is effective for inducing diabetes in dogs, and morbidity and mortality rates are lower than those reported in the literature with other described techniques.
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Aloxano/administración & dosificación , Aorta Abdominal/fisiología , Oclusión con Balón , Diabetes Mellitus Experimental/inducido químicamente , Infusiones Intraarteriales/métodos , Estreptozocina/administración & dosificación , Animales , Diabetes Mellitus Experimental/mortalidad , Perros , FemeninoAsunto(s)
Fístula Arteriovenosa/diagnóstico por imagen , Fístula Arteriovenosa/terapia , Embolización Terapéutica , Bazo/lesiones , Arteria Esplénica/lesiones , Vena Esplénica/lesiones , Accidentes de Tránsito , Adolescente , Fístula Arteriovenosa/etiología , Diagnóstico Diferencial , Humanos , Masculino , Motocicletas , Bazo/diagnóstico por imagen , Arteria Esplénica/diagnóstico por imagen , Vena Esplénica/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/complicaciones , Heridas no Penetrantes/diagnóstico por imagenRESUMEN
Missed lung cancer is an important medicolegal issue and is the second leading cause for malpractice actions against radiologists. Contributing factors to overlooked lung cancer can be ascribed to observer performance, lesion characteristics, and technical considerations. Of these, errors related to observer performance are probably the most important. Missed lung cancer does not necessarily constitute malpractice, but lesions of high conspicuity are more likely to be associated with an adverse legal outcome. Multiple strategies have been advocated to reduce the frequency of missed lung cancer. Several studies have emphasized the importance of careful comparison of the current radiograph with one or more prior examinations.
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Medicina Legal , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Competencia Clínica , Errores Diagnósticos , Estudios de Seguimiento , Humanos , Mala Praxis/legislación & jurisprudencia , Radiografía Torácica , Radiología/legislación & jurisprudencia , Nódulo Pulmonar Solitario/diagnóstico por imagen , Tecnología RadiológicaRESUMEN
High quality arteriographic studies of the iliopudendal vascular tree are mandatory for the correct examination of arteriogenic impotence patients before revascularization procedures. Twenty-three patients with chronic erectile dysfunctions due to stenosis or occlusive arteries diseases of the iliac arteries were treated with percutaneous transluminal angioplasty (PTA) in our Department. A positive clinical result was obtained in 15 of 23 cases (65.2%). The maneuver was successful in 8 of 14 patients with vascular lesions of the common and/or external iliac artery (57%). The erectile dysfunction was resolved in 4 of 6 patients with stenosis of the external iliac artery associated with a stenosis of the hypogastric artery (66.6%). The erectile dysfunction was also resolved in 3 patients with a single vascular lesion in the hypogastric artery. No major post-angioplasty complications were observed. PTA is a repeatable and not very invasive method with a low complication rate and could represent a valuable alternative to surgical revascularization in the patients with associated impotence and claudication of leg and hip. Moreover, it makes the treatment of choice in the patients with erectile dysfunctions due to isolated lesions of the hypogastric arteries.