RESUMEN
Elective cerclage is a rare procedure, but is reported to be relatively more common in developing countries. This variation in rate may be reflected in a multi-ethnic population as seen in London. Our study analysed the epidemiology and rate of elective cerclage performed in a London district general hospital. Factors contributing to the outcome of the procedures were also reviewed. A total of 41 elective cerclages were performed in the hospital between 2000 and 2007. Data from these were collected retrospectively, including maternal history, operative details, and gestational age at delivery. Fisher's exact test was used for statistical analysis. Of the 41 cases, 19 pregnancies were carried to term (>or=37 weeks' gestation), nine were pre-term (24-36 weeks' gestation) and seven miscarried (<24 weeks' gestation); six cases had not yet delivered. All of the patients were immigrants from developing countries but ethnicity did not affect the operative outcome (p = 0.89, Fisher's exact). The other factors studied were also noted to have no significant impact on success. These included cervical length at insertion (p = 1.00, Fisher's exact), type of suture (p = 0.90, Fisher's exact) and average gestation at insertion (p = 0.20, Fisher's exact). In conclusion, all patients requiring intervention in this study originated from developing countries. This is a disproportionately high figure relative to the demographic breakdown of the study population. Such a finding may be due to geographical variation of risk factors for cervical incompetence but may also be influenced by observer bias. Additional studies are needed to further investigate the influence of ethnicity on the rate of elective cerclage. None of the variables analysed in this study significantly affected the outcome of the procedure.
Asunto(s)
Cerclaje Cervical/estadística & datos numéricos , Procedimientos Quirúrgicos Electivos/estadística & datos numéricos , Emigrantes e Inmigrantes/estadística & datos numéricos , Países en Desarrollo , Femenino , Hospitales Generales/estadística & datos numéricos , Humanos , Londres/epidemiología , Embarazo , Estudios RetrospectivosRESUMEN
A new procedure was devised for reversibly removing the flavin from flavocytochrome b2. It allowed reconstitution with selectively enriched 13C- and 15N-labelled FMN for an NMR analysis of the chemical shifts of the enriched positions as well as that of 31P. From these measurements, it was possible to deduce information about the hydrogen-bonding pattern of FMN in the protein, the hybridization states of the nitrogen atoms and (in part) the pi-electron distribution. The carbonyl groups at C(2) and C(4) and the nitrogen atoms N(1) and N(5) form hydrogen bonds to the apoenzyme in both redox states. Nevertheless, according to 15N-chemical shifts, the bond from the protein to N(3) is very weak in both redox states, whereas that to N(5) is strong for the oxidized state, and is weakened upon flavin reduction. On the other hand, the 13C-NMR results indicate that the C(2) and C(4) carbonyl oxygens form stronger hydrogen bonds with the enzyme than most other flavoproteins in both redox states. From coupling constant measurements it is shown that the N(3) proton is not solvent accessible. Although no N-H coupling constant could be measured for N(5) in the reduced state due to lack of resolution, N(5) is clearly protonated in flavocytochrome b2 as in all other known flavoproteins. With respect to N(10), it is more sp3-hybridized in the oxidized state than in free FMN, whereas the other nitrogen atoms show a nearly planar structure. In the reduced state, N(5) and N(10) in bound FMN are both more sp3-hybridized than in free FMN, but N(5) exhibits a higher degree of sp3-hybridization than N(10), which is only slightly shifted out of the isoalloxazine plane. In addition, two-electron reduction of the enzyme leads to anion formation on N(1), as indicated by its 15N-chemical shift of N(1) and characteristic upfield shifts of the resonances of C(2), C(4) and C(4a) compared to the oxidized state, as observed for most flavoproteins. 31P-NMR measurements show that the phosphate geometry has changed in enzyme bound FMN compared to the free flavin in water, indicating a strong interaction of the phosphate group with the apoenzyme.
Asunto(s)
Mononucleótido de Flavina/química , Mononucleótido de Flavina/metabolismo , L-Lactato Deshidrogenasa/química , L-Lactato Deshidrogenasa/metabolismo , Sitios de Unión , Isótopos de Carbono , Clonación Molecular , Escherichia coli , Flavina-Adenina Dinucleótido/metabolismo , Flavoproteínas/química , Flavoproteínas/metabolismo , Enlace de Hidrógeno , L-Lactato Deshidrogenasa (Citocromo) , Conformación Molecular , Isótopos de Nitrógeno , Resonancia Magnética Nuclear Biomolecular/métodos , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Riboflavina/química , Riboflavina/metabolismo , Saccharomyces cerevisiae/enzimologíaAsunto(s)
Cromatografía en Agarosa/métodos , Mononucleótido de Flavina/aislamiento & purificación , Flavina-Adenina Dinucleótido/aislamiento & purificación , Flavinas/aislamiento & purificación , Flavoproteínas/química , Flavoproteínas/metabolismo , L-Lactato Deshidrogenasa/química , L-Lactato Deshidrogenasa/metabolismo , L-Lactato Deshidrogenasa (Citocromo)RESUMEN
Cyclosporine A (CyA) has been recommended for the treatment of severe steroid-resistant ulcerative colitis, however, long-term results are scarce. We prospectively followed a treatment plan in 14 patients with severe ulcerative colitis receiving intravenous CyA after failure to respond to at least eight days of standard therapy with prednisolone (1-1.5 mg/kg/day). CyA was delivered in a daily dose of 5 mg/kg i.v. for a mean of 14 days (range 7-28) in addition to ongoing medical therapy. CyA whole blood levels were monitored by HPLC and maintained between 100 ng/ml and 400 ng/ml. Responders were switched to oral CyA (5-7.5 mg/kg/day) for a mean of two months, and steroids were gradually tapered. Eleven patients (79%) initially responded to i.v. CyA, three patients failed to respond and underwent urgent colectomy. Time until response averaged seven days (range 3-13). Four of the eleven responders underwent colectomy because of severe relapse after one, eleven, twelve and 13 months of follow-up. The remaining seven patients were followed for a median of 48 months. During the first year of follow-up three out of seven had a severe relapse and responded to steroids (two patients) or to a further course of i.v. CyA (one patient). During CyA therapy one patient developed staphylococcal sepsis, other adverse events were mild and reversible. The results confirm that CyA is effective in severe steroid-refractory ulcerative colitis. Severe relapse and colectomy are uncommon after the first year of follow-up and the colon preserving effect of CyA can be maintained in up to 50% of patients over a period of four years.
Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Ciclosporina/administración & dosificación , Inmunosupresores/administración & dosificación , Adulto , Colectomía , Colitis Ulcerosa/inmunología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Prednisolona/administración & dosificación , Prednisolona/efectos adversos , Estudios Prospectivos , Recurrencia , Insuficiencia del Tratamiento , Resultado del TratamientoRESUMEN
Spiral CT venography is a technical innovation in vascular imaging that can optimize vessel contrast in the deep venous system and, therefore, is an accurate diagnostic tool to detect deep venous thrombosis. Compared with conventional venography, the amount of contrast material can be reduced by 80%. While using spiral CT as the primary imaging technique for the detection of pulmonary embolism, the cause of embolism can be evaluated within a short period of additional imaging time without further patient mobilization. This review outlines fundamental techniques in spiral CT venography and summarizes our clinical experience at Vienna University Medical Center.
Asunto(s)
Tromboflebitis/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Medios de Contraste , Femenino , Estudios de Seguimiento , Humanos , Procesamiento de Imagen Asistido por Computador , Yohexol , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Flebografía , Recurrencia , Reproducibilidad de los Resultados , Estudios RetrospectivosAsunto(s)
Desulfovibrio vulgaris/enzimología , Flavoproteínas/química , L-Lactato Deshidrogenasa/química , L-Lactato Deshidrogenasa/metabolismo , Conformación Proteica , Mononucleótido de Flavina/metabolismo , Flavoproteínas/metabolismo , Enlace de Hidrógeno , L-Lactato Deshidrogenasa (Citocromo) , Espectroscopía de Resonancia Magnética/métodos , Modelos Estructurales , Oxidación-Reducción , Estructura Secundaria de ProteínaRESUMEN
Consumption of a plant-based diet can prevent the development and progression of chronic diseases that are associated with extensive neovascularization; however, little is known about the mechanisms. To determine whether prevention might be associated with dietary-derived angiogenesis inhibitors, we have fractionated urine of healthy human subjects consuming a plant-based diet and examined the fractions for their abilities to inhibit the proliferation of vascular endothelial cells. Using gas chromatography-mass spectrometry, we showed that one of the most potent fractions contained several isoflavonoids, which we subsequently synthesized. Of all synthetic compounds, the isoflavonoid genistein was the most potent and inhibited endothelial cell proliferation and in vitro angiogenesis at concentrations giving half-maximal inhibition of 5 and 150 microM, respectively. As we have previously demonstrated, genistein concentrations in urine of subjects consuming a plant-based diet are in the micromolar range, while those of subjects consuming a traditional Western diet are lower by a factor of > 30. The high excretion of genistein in urine of vegetarians and our present results suggest that genistein may contribute to the preventive effect of a plant-based diet on chronic diseases, including solid tumors, by inhibiting neovascularization. Thus, genistein may represent a member of a new class of dietary-derived anti-angiogenic compounds.
Asunto(s)
Dieta Vegetariana , Endotelio Vascular/efectos de los fármacos , Inhibidores de Crecimiento/orina , Isoflavonas/farmacología , Isoflavonas/orina , Neovascularización Patológica , Corteza Suprarrenal/irrigación sanguínea , Animales , Capilares , Bovinos , División Celular/efectos de los fármacos , Células Cultivadas , Circulación Cerebrovascular , Cromatografía por Intercambio Iónico , Células Clonales , Endotelio Vascular/citología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Genisteína , Inhibidores de Crecimiento/farmacología , Humanos , Isoflavonas/aislamiento & purificación , Estructura Molecular , Glycine maxRESUMEN
Partially purified urine of healthy human subjects contains several fractions able to inhibit the proliferation of cultured human neuroblastoma cells. One of the most active fractions was further analysed by gas chromatography-mass spectrometry and shown to contain genistein, a substance formed in the human body from precursors obtained by diet. Synthetic genistein was able to inhibit the proliferation of human neuroblastoma cells with a half-maximal effect at 5-10 mumol l-1 concentrations. Genistein displayed similar potencies in inhibiting the proliferation of cells derived from various other solid pediatric tumours. Our results suggest that genistein is a natural antineoplastic agent present in diet and that it could be useful for the therapy of paediatric tumours.
Asunto(s)
Inhibidores de Crecimiento/orina , Isoflavonas/orina , Neoplasias/orina , División Celular/efectos de los fármacos , Niño , Genisteína , Inhibidores de Crecimiento/química , Inhibidores de Crecimiento/farmacología , Humanos , Isoflavonas/química , Isoflavonas/farmacología , Estructura Molecular , Neuroblastoma/tratamiento farmacológico , Relación Estructura-Actividad , Células Tumorales Cultivadas/efectos de los fármacosRESUMEN
We have examined the effect of human basic fibroblast growth factor (bFGF) on the proliferation of human neuroblastoma cells with normal and enhanced MYCN oncogene expression. bFGF stimulated the proliferation of the neuroblastoma cells with enhanced, but not normal, MYCN expression. Both cell species express FGFR-1, but not FGFR-2, receptors and both harbor FGF receptor species of Mr 145.000, but they differ in their pattern of lower and higher-molecular weight FGF receptor species. Our results demonstrate that enhanced MYCN expression confers to neuroblastoma cells the ability to respond to bFGF, possibly by inducing functional FGF receptors. This mechanism may contribute to the advanced malignant phenotype of human neuroblastomas with enhanced MYCN expression.
Asunto(s)
División Celular/efectos de los fármacos , Factor 2 de Crecimiento de Fibroblastos/farmacología , Regulación Neoplásica de la Expresión Génica , Genes myc , Receptores de Superficie Celular/genética , Northern Blotting , Línea Celular , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Humanos , Cinética , Neuroblastoma , ARN Neoplásico/genética , ARN Neoplásico/aislamiento & purificación , Receptores de Superficie Celular/metabolismo , Receptores de Factores de Crecimiento de FibroblastosRESUMEN
A non-histone chromosomal protein of Mr = 75,000 was isolated from Drosophila embryos. The distribution pattern of this protein was determined by indirect immunofluorescence on salivary gland chromosomes of Drosophila melanogaster third instar larvae and compared with the distribution pattern of RNA polymerase II. Despite its preferential association with transcriptionally active regions of the chromosomes there was in many cases an almost inverse correlation with the RNA polymerase II content of a given locus. We postulate a function of the Mr = 75,000 protein in posttranscriptional regulation of gene expression by storing the newly synthesized RNA.
Asunto(s)
Proteínas Cromosómicas no Histona/aislamiento & purificación , Drosophila melanogaster/genética , Animales , Núcleo Celular , Proteínas Cromosómicas no Histona/análisis , Mapeo Cromosómico , Electroforesis en Gel de Poliacrilamida , Larva , ARN Polimerasa II/análisis , Conejos , Transcripción GenéticaRESUMEN
The distribution patterns of chromosomal proteins from Drosophila can be observed by immunofluorescent staining of the polytene chromosomes from larval salivary glands. We have purified a non-histone chromosomal protein of Mr = 69,000 molecular weight which has a high affinity for DNA with little sequence specificity. Immunofluorescent staining indicates that this protein is preferentially associated with the inactive portions of the genome, including the centric heterochromatin and the condensed bands within the euchromatic arms of the chromosomes. Observation of both the heat shock loci 87A and 87C and the developmentally regulated loci 74EF and 75B shows an inverse correlation between immunofluorescent staining for the Mr = 69,000 protein and for RNA polymerase. The presence of this protein appears to be correlated with the packaging of the chromatin in an inactive form.
Asunto(s)
Proteínas Cromosómicas no Histona/aislamiento & purificación , Drosophila melanogaster/metabolismo , Animales , Proteínas Cromosómicas no Histona/metabolismo , Cromosomas/metabolismo , ADN/metabolismo , Drosophila melanogaster/genética , Genes , Peso MolecularRESUMEN
Previous work from this laboratory had shown that Leguminosa seed extracts contain lectin-bound proteins. In the present paper, the isolation of protein bodies from the seeds of 7 Leguminosa species (Canavalia ensiformis, Lens culinaris, Pisum sativum, Glycine max, Sophora japonica, Wisteria floribunda and Phaseolus vulgaris) is described. Protein bodies were characterized microscopically and by their constituents, storage proteins, lectins and some glycosidases. From the protein bodies, lectin-bound proteins were isolated and were shown to be identical with those from whole seed extracts. This indicates a common localization of lectin-bound proteins and of lectins. Lectin-bound proteins belong to the storage proteins and to the proteins with glycosidase activity. The common localization of these proteins and interactions between them suggest a biological role of seed lectins: during maturation they may act as a packaging aid for storage proteins and enzymes into developing protein bodies. Lectins thus may contribute to an ordered construction and degradation of protein bodies.
Asunto(s)
Lectinas/metabolismo , Proteínas de Plantas/metabolismo , Electroforesis en Gel de Poliacrilamida , Fabaceae/metabolismo , Glicósido Hidrolasas/aislamiento & purificación , Glicósido Hidrolasas/metabolismo , Lectinas/aislamiento & purificación , Peso Molecular , Lectinas de Plantas , Proteínas de Plantas/aislamiento & purificación , Plantas Medicinales , Unión Proteica , Semillas/metabolismo , Especificidad de la EspecieRESUMEN
Two lectins from the seeds of Robinia pseudoacacia were isolated and resolved in a single affinity chromatography run using immobilized ovomucoid by successive elution with different buffers. The lectins were characterized by their subunit sizes, total molecular masses and isoelectric points as well as by their ability to bind to ConA-Sepharose and to stimulate mitosis in murine lymphocytes.
Asunto(s)
Lectinas/aislamiento & purificación , Animales , Cromatografía de Afinidad , Electroforesis en Gel de Poliacrilamida , Hemaglutinación , Activación de Linfocitos , Linfocitos/citología , Ratones , Ratones Endogámicos BALB C , Mitosis , Peso Molecular , OvomucinaRESUMEN
Two affinity adsorbents of general applicability for isolating of plant lectins are presented. The isolation of 30 lectins from 27 plants is described. The method works quickly and is inexpensive. In particular, mixtures of different lectins occurring in some plants may be resolved in one run.
Asunto(s)
Proteínas del Huevo/análisis , Lectinas/aislamiento & purificación , Mucinas/análisis , Ovomucina/análisis , Animales , Antígenos de Grupos Sanguíneos , Cromatografía de Afinidad , Electroforesis en Gel de Poliacrilamida , Peso Molecular , PorcinosRESUMEN
A new fast-working one-step method for the resolution of the Phaseolus vulgaris isolectins is described which requires inexpensive materials.
Asunto(s)
Fitohemaglutininas/aislamiento & purificación , Cromatografía de Afinidad , Electroforesis en Gel de Poliacrilamida , Humanos , Técnicas In Vitro , Activación de Linfocitos , Fitohemaglutininas/farmacologíaRESUMEN
The larynx may be involved in patients with systemic sarcoidosis or may be the first or only manifestation of the disease. The symptoms depend on the degree of involvement of the larynx, and include a sensation of lump in the throat, dysphagia, hoarseness, cough, stridor and dyspnea. The supraglottis is the most frequently affected area. There are pale pink, edematous, diffuse hypertrophy of the supraglottic structures or granular areas of the glottic and subglottic region. The diagnosis is made by the characteristic appearance of the larynx, histologic and laboratory findings and exclusion of other granulomatous diseases. Laryngeal sarcoidosis may cause life-threatening upper airway obstruction. Systemic corticosteroid therapy is the treatment of choice in most cases, but surgical excision or local steroid injections are useful in selected cases.
Asunto(s)
Enfermedades de la Laringe/diagnóstico , Sarcoidosis/diagnóstico , Adulto , Terapia Combinada , Diagnóstico Diferencial , Femenino , Radioisótopos de Galio , Humanos , Enfermedades de la Laringe/diagnóstico por imagen , Enfermedades de la Laringe/terapia , Laringoscopía , Prednisolona/uso terapéutico , Cintigrafía , Sarcoidosis/diagnóstico por imagen , Sarcoidosis/terapia , Prueba de TuberculinaRESUMEN
The distribution of DNA topoisomerase I within Drosophila polytene chromosomes was observed by immunofluorescent staining with affinity-purified antibodies. The enzyme is preferentially associated with active loci, as shown by prominent staining of puffs. The heat shock loci 87A-87C are stained after, but not before, heat shock induction. A detailed comparison of the distribution of topoisomerase I with that of RNA polymerase II reveals a similar, although not identical, pattern of association. Topoisomerase I is also found in association with the nucleolus, the site of transcription by RNA polymerase I.