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1.
Artículo en Inglés | MEDLINE | ID: mdl-38642342

RESUMEN

OBJECTIVES: The finding of an abdominal cyst during pregnancy has an estimated prevalence of 1 in 1000 pregnancies, mostly in second and third trimester. The detection of a fetal abdominal cyst during the first trimester scan is a rare event, whose natural history and prognosis are often unknown and unpredictable as these anomalies can be related to various underlying conditions and originate from different structures. The aim of this study is to evaluate the outcome of fetal abdominal cysts detected in the first trimester in order to understand their possible clinical significance and to offer the proper management according to the available data. METHODS: We present a case report of a first trimester fetal abdominal cyst detected with subsequent diagnosis of congenital multiple arthrogryposis and we performed a systematic review of the literature to identify the incidence and the outcomes of similar cases. The systematic literature review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement 25 and registered with PROSPERO (CRD42023491729). RESULTS: A total of 60 cases of first trimester abdominal cysts were included. Of these, 35% were associated with concurrent or late onset structural anomalies, as in our case report, and 65% were isolated. In pregnancies with isolated fetal abdominal cysts, 56% had a completely normal outcome. CONCLUSIONS: The finding of an abdominal cyst during the first trimester of pregnancy is in most cases an isolated event with a moderate to good prognosis but it could also be an early sign of other associated abnormalities, including arthrogryposis. Increased ultrasound surveillance and additional genetic testing to rule out possible associated anomalies are pivotal to assess the risk of adverse pregnancy outcomes and to provide appropriate counselling to the patient. This article is protected by copyright. All rights reserved.

2.
Genome ; 57(2): 111-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24702068

RESUMEN

Thirty-seven grapevine accessions, collected in Central Italy, were characterized by morphological and genetic analysis, according to guidelines developed by European Union programs of grapevine research and standardization. Traditional denominations of some sampled varieties were revealed to be incorrect; moreover, 10 synonymies and 12 homonymies were recognized. Ampelographic and ampelometric measurements of leaf characters were performed. These data generated a phenotypic similarity matrix and a relative diagram showing morphological differences between specimens. Many samples presented different morphology even in the presence of the same genotype, probably as a result of various environmental pressures. Grapevines were typed by 12 microsatellite loci and then compared with the CRA-VIT genetic resource database. Twenty-five SSR profiles were clearly identified as well-known cultivars, while nine genotypes did not find a direct correspondence: these samples could represent putative new autochthonous Latial Vitis vinifera cultivars or hybrid varieties. The genetic approach also detected three new (169 and 173 in VVMD27 locus; 179 in ISV2 locus) and seven rare allelic variants. Plant sample classification by oral history, morphological observations, and molecular results were compared and discussed. Scions of samples were planted in the Botanic Garden of the University of Rome "Tor Vergata", to preserve grapevine biodiversity and to protect possible new autochthonous varieties.


Asunto(s)
ADN de Plantas/genética , Vitis/clasificación , Vitis/genética , Alelos , Variación Genética , Genética de Población , Genotipo , Repeticiones de Microsatélite/genética , Filogenia , Hojas de la Planta/clasificación
3.
Plant Biol (Stuttg) ; 16(4): 792-800, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24118651

RESUMEN

Environmental antibiotic contamination is due mainly to improper and illegal disposal of these molecules that, yet pharmacologically active, are excreted by humans and animals. These compounds contaminate soil, water and plants. Many studies have reported the bioaccumulation of antibiotics in plants and their negative effects on photosynthesis, cell growth and oxidative balance. Therefore, the principal objective of this paper was the study of antibiotic accumulation sites in plants and its uptake modality. Iberis sempervirens L., grown in soil and in agar in the presence or absence of tetracycline, were used as a model system. Using confocal and transmission electron microscopy, we demonstrated that tetracycline was absorbed and propagated in plants through apoplastic transport and also accumulated in intercellular spaces. Tetracycline was rarely detected inside cells (in cytoplasm and mitochondria where, coherent to its pharmacological activity, it probably affected ribosomes), except in stomata. Moreover, we verified and clarified further the phytotoxic effects of tetracycline on plants. We observed that the antibiotic induced a large reduction in plant growth and development and inhibition of photosynthetic activity. As tetracycline may lead to oxidative stress in plants, plant cells tried to balance this disequilibrium by increasing the amount and activity of some endogenous enzyme antioxidant agents (superoxide dismutase 1 and catalase) and levels of antiradical secondary metabolites.


Asunto(s)
Transporte Biológico/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Tetraciclina/metabolismo , Tetraciclina/farmacología , Brassicaceae/efectos de los fármacos , Brassicaceae/metabolismo , Microscopía Confocal , Microscopía Electrónica de Transmisión
6.
Eur Phys J E Soft Matter ; 27(4): 365-73, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19015903

RESUMEN

The process of re-crystallization in poly(ethylene terephthalate) is studied by means of X-ray diffraction (SAXS and WAXS) and dynamical mechanical thermal analysis. Samples cold-crystallized for 9h at the temperatures T(c) = 100°C and T (c) = 160°C, i.e. in the middle of the alpha relaxation region and close to its upper bound, respectively, are analyzed. During heating from room temperature, a structural rearrangement of the stacks is always found at T (r) approximately T (c) + 20°C. This process is characterized by a decrease of the linear crystallinity, irrespective of T(c); on the other hand, the WAXS crystallinity never increases with T below T(c+30)°C. The lamellar thickness in the low-T(c) sample decreases significantly after the structural transition, whereas in the high-T(c) sample the lamellar thickness remains almost unchanged. In both, high- and low-T(c), the interlamellar thickness increases above T(r). Moreover, the high-T(c) sample shows a lower rate of decrease of the mechanical performance with increasing T as the threshold T(r) is crossed. This result is interpreted in terms of the formation of rigid amorphous domains where the chains are partially oriented. The presence of these domains would determine i) the stabilization of the crystalline lamellae from the thermodynamic point of view and ii) the increase of the elastic modulus of the amorphous interlamellar regions. This idea is discussed by resorting to a phase diagram. An estimation of the chemical-potential increase of the interlamellar amorphous regions, due to the enhancement of the structural constraints hindering segmental mobility, is offered. Finally, previous calculations developed within the framework of the Gaussian chain model (F.J. Baltá Calleja et al., Phys. Rev. B 75, 224201 (2007)) are used here to estimate the degree of chain orientation induced by the structural transition of the stacks.

7.
Am J Physiol Renal Physiol ; 294(6): F1381-7, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18385273

RESUMEN

Chronic kidney disease with hyperphosphatemia is associated with accelerated atherosclerosis and endothelial dysfunction. However, the contribution of high serum phosphate levels to endothelial injury is incompletely understood. The aim of this work was to evaluate the responses of endothelial cells to elevated levels of extracellular phosphate in vitro. High phosphate in concentrations similar to those observed in uremia-associated hyperphosphatemia (>2.5 mM) induced apoptosis in two endothelial cell lines (EAhy926 cells and GM-7373 cells). This effect was enhanced when cells were incubated for 24 h in the presence of 2.8 mM calcium instead of 1.8 mM. By treating cells with 0.5 or 1.0 mM phosphonoformic acid, an inhibitor of the phosphate transporter, death was completely prevented. The process of phosphate-induced apoptosis was further characterized by increased oxidative stress, as detected by increased ROS generation and disruption of the mitochondrial membrane potential at approximately 2 h after treatment, followed by caspase activation. These findings show that hyperphosphatemia causes endothelial cell apoptosis, a process that impairs endothelial integrity. Endothelial cell injury induced by high phosphate concentrations may be an initial event leading to vascular complications in patients with chronic kidney disease.


Asunto(s)
Apoptosis/efectos de los fármacos , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Hiperfosfatemia/patología , Fosfatos/farmacología , Clorometilcetonas de Aminoácidos/farmacología , Aterosclerosis/metabolismo , Aterosclerosis/patología , Calcio/farmacología , Inhibidores de Caspasas , Células Cultivadas , Inhibidores de Cisteína Proteinasa/farmacología , Expresión Génica/efectos de los fármacos , Humanos , Hiperfosfatemia/metabolismo , Técnicas In Vitro , Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/patología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Proteínas Cotransportadoras de Sodio-Fosfato/genética , Venas Umbilicales/citología
8.
J Appl Microbiol ; 105(5): 1694-702, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19149767

RESUMEN

AIMS: In this study, we evaluated the removal efficiency of fuel hydrocarbons from a jet fuel contaminated area using bioaugmentation treatment in biopile. METHODS AND RESULTS: The hydrocarbon analysis of the sample revealed total hydrocarbons mainly constituted by benzene, toluene, ethylbenzene, xylenes (BTEX) and heavy aliphatic hydrocarbons. Enrichments of soil sample were performed with BTEX, pristane and fuel JP-5, respectively, selected hydrocarbon-degrading strains, namely Acinetobacter sp., Pseudomonas sp. and Rhodococcus sp. Three hundred litres of culture containing 10(8) cell ml(-1) of each strain and nutrients sprayed on the biopile allowed a removal of 90% of total hydrocarbons in 15 days. Bioremediation process was monitored by observation of the respiration rate and the bacterial abundance and GC-MS analysis. CONCLUSIONS: The efficiency of the treatment in the biopile was considerable. The assessment of microbial activity during the experiment is necessary for interventions targeted to improve environmental parameters such as humidity, temperature, pH and nutrients for optimization of the bioremediation process. SIGNIFICANCE AND IMPACT OF THE STUDY: A better knowledge of microbial successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in biopile study improve our understanding of processes occurring during oil pollution.


Asunto(s)
Bacterias/metabolismo , Restauración y Remediación Ambiental/métodos , Hidrocarburos/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Bacterias/crecimiento & desarrollo , Benceno/metabolismo , Derivados del Benceno/metabolismo , Biodegradación Ambiental , Recuento de Colonia Microbiana/métodos , Respiración , Tolueno/metabolismo , Xilenos/metabolismo
9.
Rev Sci Instrum ; 78(10): 103702, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17979423

RESUMEN

We present a method to produce sharp gold tips for applications in apertureless near-field optical microscopy and spectroscopy. Thin gold wires are tapered by chemical etching in aqua regia, covered by an isooctane protective layer. Tips with apical radii of curvature of <50 nm are obtained with a 40% yield. The tip performances have been checked by shear-force imaging of amyloid fibrils samples and compared to optical fiber probes. The analysis of the tip morphology, carried out by scanning electron microscopy, shows the existence of two different etching processes occurring in bulk and at the liquid-liquid interface. A simple analytical model is presented to describe the dynamics of the tip formation at the liquid-liquid meniscus interface that fits remarkably well the experimental results in terms of tip shape and length.


Asunto(s)
Galvanoplastia/métodos , Oro/química , Microscopía de Sonda de Barrido/instrumentación , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/instrumentación , Transductores , Diseño de Equipo , Análisis de Falla de Equipo , Microscopía de Sonda de Barrido/métodos , Nanotecnología/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Propiedades de Superficie
10.
J Mater Sci Mater Med ; 18(12): 2331-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17569008

RESUMEN

Calcium phosphate cement (CPC) samples have been prepared with a mixture of monocalciumphosphate monohydrate (MCPM) and calcium carbonate (CC) powders, in stechiometric moles ratio 1:2.5 to obtain a Ca/P ratio of about 1.67 typical of hydroxyapatite (HAp), with or without addition of HAp. All specimens are incubated at 30 degrees C in a steam saturated air environment for 3, 6 and 15 days respectively, afterwards dried and stored under nitrogen. The calcium phosphate samples have been characterized by X-ray diffraction (XRD), Vickers hardness test (HV), diametral compression (d.c.), strength compression, and porosity evaluation. MCPM/CC mixture has a 30% HAp final concentration and is characterized by higher porosity (amount 78%) and mechanical properties useful as filler in bone segments without high mechanical stress.


Asunto(s)
Materiales Biocompatibles/síntesis química , Fosfatos de Calcio/síntesis química , Cementos para Huesos , Sustitutos de Huesos , Carbonato de Calcio/química , Fosfatos de Calcio/química , Durapatita/química , Materiales Manufacturados/análisis , Polvos/síntesis química , Polvos/química , Difracción de Rayos X
11.
Kidney Int ; 69(6): 974-80, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16528246

RESUMEN

Hyperactivation of systemic renin-angiotensin system (RAS) during sepsis is well documented. However, the behavior of intrarenal RAS in the context of endotoxemia is yet to be defined. The present study evaluates the direct effect of Escherichia coli lipopolysaccharide (LPS) on immortalized human mesangial cell (HMC) RAS. Quiescent HMC were incubated with vehicle or LPS (1-100 microg/ml), and levels of angiotensin I and II (Ang I and II) and their metabolites were analyzed by high-performance liquid chromatography. In addition, angiotensin-converting enzyme (ACE) and renin activity were also investigated. Cell lysate and extracellular medium levels of Ang II were rapidly reduced (1 h) in a time- and concentration-dependent manner, reaching a significant -9 fold-change (P<0.001) after 3 h of LPS incubation. Similar results were obtained for Ang I levels (-3 fold-change, P<0.001). We ruled out Ang I and II degradation, as levels of their metabolic fragments were also significantly decreased by LPS. ACE activity was slightly increased following LPS incubation. On the other hand, renin activity was significantly inhibited, as Ang I concentration elevation following exogenous angiotensinogen administration was blunted by LPS (-60% vs vehicle, P<0.001). Renin and angiotensinogen protein levels were not affected by LPS according to Western blot analysis. Taken together, these data demonstrate for the first time that LPS significantly downregulates HMC RAS through inhibition of renin or renin-like activity. These findings are potentially related to the development of and/or recovery from acute renal failure in the context of sepsis.


Asunto(s)
Angiotensina II/metabolismo , Escherichia coli/química , Lipopolisacáridos/análisis , Lipopolisacáridos/farmacología , Células Mesangiales/efectos de los fármacos , Renina/efectos de los fármacos , Angiotensina I/análisis , Angiotensina I/metabolismo , Angiotensina II/análisis , Angiotensinógeno/farmacología , Western Blotting , Línea Celular , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Endotoxemia/fisiopatología , Humanos , Células Mesangiales/química , Células Mesangiales/fisiología , Peptidil-Dipeptidasa A/análisis , Peptidil-Dipeptidasa A/fisiología , Renina/análisis , Renina/antagonistas & inhibidores , Renina/fisiología , Sistema Renina-Angiotensina/efectos de los fármacos , Sistema Renina-Angiotensina/fisiología , Factores de Tiempo
13.
Braz J Med Biol Res ; 38(4): 577-82, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15962183

RESUMEN

The objective of the present study was to evaluate the role of physical exercise as well as the influence of hydration with an isotonic sports drink on renal function in male Wistar rats. Four groups were studied over a period of 42 days: 1) control (N = 9); 2) physical exercise (Exe, N = 7); 3) isotonic drink (Drink, N = 8); 4) physical exercise + isotonic drink (Exe + Drink, N = 8). Physical exercise consisted of running on a motor-driven treadmill for 1 h/day, at 20 m/min, 5 days a week. The isotonic sports drink was a commercial solution used by athletes for rehydration after physical activity, 2 ml administered by gavage twice a day. Urine cultures were performed in all animals. Twenty-four-hour urine samples were collected in metabolic cages at the beginning and at the end of the protocol period. Urinary and plasma parameters (sodium, potassium, urea, creatinine, calcium) did not differ among groups. However, an amorphous material was observed in the bladders of animals in the Exe + Drink and Drink groups. Characterization of the material by Western blot revealed the presence of Tamm-Horsfall protein and angiotensin converting enzyme. Physical exercise and the isotonic drink did not change the plasma or urinary parameters measured. However, the isotonic drink induced the formation of intravesical matrix, suggesting a potential lithogenic risk.


Asunto(s)
Bebidas/efectos adversos , Soluciones Isotónicas/efectos adversos , Cálculos Renales/inducido químicamente , Riñón/fisiología , Condicionamiento Físico Animal , Soluciones para Rehidratación/efectos adversos , Animales , Biomarcadores/sangre , Biomarcadores/orina , Western Blotting , Masculino , Mucoproteínas/orina , Ratas , Ratas Wistar , Factores de Riesgo , Uromodulina
14.
Braz. j. med. biol. res ; 38(4): 577-582, Apr. 2005. tab
Artículo en Inglés | LILACS | ID: lil-398185

RESUMEN

The objective of the present study was to evaluate the role of physical exercise as well as the influence of hydration with an isotonic sports drink on renal function in male Wistar rats. Four groups were studied over a period of 42 days: 1) control (N = 9); 2) physical exercise (Exe, N = 7); 3) isotonic drink (Drink, N = 8); 4) physical exercise + isotonic drink (Exe + Drink, N = 8). Physical exercise consisted of running on a motor-driven treadmill for 1 h/day, at 20 m/min, 5 days a week. The isotonic sports drink was a commercial solution used by athletes for rehydration after physical activity, 2 ml administered by gavage twice a day. Urine cultures were performed in all animals. Twenty-four-hour urine samples were collected in metabolic cages at the beginning and at the end of the protocol period. Urinary and plasma parameters (sodium, potassium, urea, creatinine, calcium) did not differ among groups. However, an amorphous material was observed in the bladders of animals in the Exe + Drink and Drink groups. Characterization of the material by Western blot revealed the presence of Tamm-Horsfall protein and angiotensin converting enzyme. Physical exercise and the isotonic drink did not change the plasma or urinary parameters measured. However, the isotonic drink induced the formation of intravesical matrix, suggesting a potential lithogenic risk.


Asunto(s)
Animales , Masculino , Ratas , Bebidas/efectos adversos , Soluciones Isotónicas/efectos adversos , Cálculos Renales/inducido químicamente , Riñón/fisiología , Condicionamiento Físico Animal , Soluciones para Rehidratación/efectos adversos , Western Blotting , Biomarcadores/sangre , Biomarcadores/orina , Mucoproteínas/orina , Ratas Wistar , Factores de Riesgo
15.
Environ Microbiol ; 7(1): 78-87, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15643938

RESUMEN

The distribution of bacterial communities terminal restriction fragment length polymorphism (T-RFLP) fingerprint patterns was evaluated at three proximal hydrocarbon-contaminated sites located within the harbour of Messina. In order to analyse the short-term variability of the individual terminal restriction fragment (T-RF) patterns, water samples were collected at the three sites on three occasions within 3 months (T(0), T(90) and T(91)). Four sample sizes, from 50 to 1000 ml for each collected sample, were analysed separately (36 total analysed samples) to evaluate the relationship between the sample size and the bacterial diversity estimates. The dominant T-RF groups mostly belonged to signatures of putative hydrocarbon-degrading bacteria, as revealed by the virtual analysis of the obtained bands. In order to test whether significant differences were occurring between the analysed samples, the Kruskal-Wallis non-parametric test was applied to the T-RF data set. Neither significant influence of the sample size nor short spatial variability within the three sampled sites was detected for each sampling time. On the contrary, significant temporal changes in the diversity of the bacterial communities were observed. These results were confirmed by the non-metric multidimensional scales (nMDS) analysis of the whole set of samples, which indicated three main groups corresponding to the three different sampling times. In summary, the T-RFLP technique, although a polymerase chain reaction-based method, proved to be a suitable technique for monitoring polluted marine environments, typically characterized by low diversity and high relative abundances of a few dominant groups.


Asunto(s)
Bacterias/clasificación , Hidrocarburos/análisis , Polimorfismo de Longitud del Fragmento de Restricción , Agua de Mar/microbiología , Contaminación del Agua , Bacterias/genética , Bacterias/aislamiento & purificación , Dermatoglifia del ADN/métodos , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Ecosistema , Hidrocarburos/metabolismo , Italia , Petróleo/análisis , Petróleo/metabolismo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
16.
Rev Laryngol Otol Rhinol (Bord) ; 120(1): 35-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10371863

RESUMEN

Adenocarcinoma "not otherwise specified" of the larynx appears to be extremely rare. We report a case of adenocarcinoma "NOS" arising in the larynx of a 72 year-old white man. The neoplasia was ALCIAN and PAS negative. Immuno-histochemical studies revealed negative immunoreactivity from NSE, chromogranins and S100; cytokeratin was positive. Electron microscopy revealed electrodense granules of varying sizes, but with no obvious central core surrounded by a limiting membrane. The patient underwent a total laryngectomy and functional neck dissection, with mandibular extension. And he is free of tumor after 4 years postoperatively.


Asunto(s)
Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patología , Adenocarcinoma/cirugía , Anciano , Humanos , Inmunohistoquímica , Neoplasias Laríngeas/cirugía , Laringectomía , Masculino , Microscopía Electrónica
17.
J Med Virol ; 58(1): 26-34, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10223542

RESUMEN

To evaluate the efficacy of a 12-month course of recombinant interferon alpha (IFN-alpha2b), and to assess predictive factors of successful response to IFN therapy in chronic active hepatitis C (HCV CAH), 242 patients with histologically proven HCV CAH were assigned randomly to two groups, one treated with IFN-alpha2b (3 MU three times weekly, intramuscularly), the other untreated. To determine the efficacy of IFN-alpha2b 12 months after therapy, a second liver biopsy was carried out on 100 treated patients and 27 untreated patients. The biochemical, virological, and serological response of patients followed up for at least 50 months after treatment was also evaluated to confirm the efficacy of IFN-alpha2b. The genotypes of infecting HCV, anti-HCV core IgM, and HCV-RNA concentrations were also analysed and the predictors of response determined by univariate and multivariate analyses. Response was defined in terms of the normalisation of aminotransferase activities and the disappearance of HCV-RNA. The overall long-term response was 39.4%. Anti-HCV core IgM levels were significantly lower in long-term responders. Patients with increased levels of IgM anti HCV core (>3.8 sample/cut-off), infected with genotype 1b were nonresponders. Liver histology improved significantly in patients with long-term response. Multivariate analysis identified three independent predictors of the likelihood of long-term response to IFN therapy: age younger than 40 years, basal anti-HCV core IgM levels < or = 3.8, and genotypes other than 1b. These data indicate that the treatment with IFN-alpha2b used in this randomised controlled trial is effective in HCV CAH. Anti-HCV core IgM was the strongest predictor of long-term response in the present study.


Asunto(s)
Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Femenino , Hepacivirus/genética , Hepacivirus/inmunología , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C Crónica/sangre , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/patología , Humanos , Interferón alfa-2 , Hígado/patología , Hígado/virología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , ARN Viral/sangre , Proteínas Recombinantes , Factores de Tiempo , Resultado del Tratamiento
18.
Pathologica ; 90(3): 302-5, 1998 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-9774862

RESUMEN

Cystic mesothelioma of peritoneum is a rare neoplasia that was identified as a individual entity by ultrastructural and immunoistochemical studies. It is more frequent in young woman and often it tends to recur. Because of its rarity and difficulty in differential diagnosis, the Authors describe a case of cystic mesothelioma observed.


Asunto(s)
Mesotelioma Quístico/patología , Neoplasias Peritoneales/patología , Adulto , Femenino , Humanos
19.
J Hypertens ; 16(12 Pt 2): 1971-8, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9886885

RESUMEN

OBJECTIVE: The aims of this study were to purify and characterize a neutral endopeptidase-like enzyme (NEP-like) in human urine and propose a rapid, sensitive and specific assay for this enzyme using the fluorogenic substrate Abz-FDQ-EDDnp, where Abz = O-aminobenzoic acid and EDDnp = N-(2,4-dinitrophenyl)ethylenediamine. METHODS: Soluble urinary NEP was purified from human urine using a DEAE-cellulose Cellex D column and gel filtration on an AcA-44 column. NEP-like activity was assayed by its ability to hydrolyse bradykinin (BK) and the fluorogenic substrates Abz-BKQ-EDDnp and Abz-FDQ-EDDnp. The Km was determined using Abz-FDQ-EDDnp as a substrate. The hydrolysis products of BK and Abz-FDQ-EDDnp were analysed by high-performance liquid chromatography (HPLC). The mol. wt was estimated by polyacrylamide gel electrophoresis and the enzyme analysed by Western blot using the antibody obtained from purified recombinant NEP expressed in Pichia pastoris yeast. RESULTS: The NEP-like was purified from human urine until homogeneity and presented a mol. wt of 94000. The substrate Abz-FDQ-EDDnp was selectively hydrolysed at the F-D bond by NEP-like and by recombinant NEP. For this substrate, the NEP-like activity was maximal at pH 7.0, although a small peak of activity was observed at pH 8.0, and the determined Km was 14 microM. The enzymatic activity was inhibited by thiorphan and phosphoramidon. In Western blot analysis, NEP-like reacted strongly with a polyclonal antibody for NEP. CONCLUSION: A NEP-like enzyme was purified from human urine. Based on the mol. wt of the isolated NEP-like enzyme, it was concluded that this enzyme was produced in the kidney. In the kidney, this enzyme may cleave the kinins filtered through the glomerulus and also the kinins produced in the distal nephron. An internally quenched fluorogenic peptide, Abz-FDQ-EDDnp, was selectively hydrolysed by NEP-like and by recombinant NEP.


Asunto(s)
Neprilisina/orina , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Inhibidores Enzimáticos/farmacología , Colorantes Fluorescentes , Humanos , Concentración de Iones de Hidrógeno , Inmunoquímica , Riñón/enzimología , Cinética , Peso Molecular , Neprilisina/antagonistas & inhibidores , Neprilisina/aislamiento & purificación , Especificidad por Sustrato
20.
Anal Chem ; 70(23): 5019-23, 1998 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21644681

RESUMEN

Oxygen quenching of the luminescence of mononuclear and dinuclear Ir(III) cyclometalated complexes immobilized in the pPEGMA matrixes has been studied. Linear Stern-Volmer plots, even when experiments at different emission wavelengths have been performed, were evidenced. Despite the different luminescence lifetimes of the chromophores in the absence of quencher, similar Stern-Volmer slopes have been calculated. This behavior was tentatively interpreted by taking into account the size and charge of the chromophores. Increased sizes and lower charges seem to enhance the sensitivity of the systems. Such findings could be of interest for the design of new solid-state luminescent oxygen sensors with improved performance.

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