Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Thromb Haemost ; 14(5): 964-72, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26845754

RESUMEN

UNLABELLED: Essentials The association of superficial vein thrombosis (SVT) with venous thromboembolism (VTE) is variable. We performed a meta-analysis to assess the prevalence of concomitant VTE in patients with SVT. Deep vein thrombosis was found in 18.1%, and pulmonary embolism in 6.9%, of SVT patients. Screening for VTE may be worthy in some SVT patients to plan adequate anticoagulant treatment. SUMMARY: Background Some studies have suggested that patients with superficial vein thrombosis (SVT) have a non-negligible risk of concomitant deep vein thrombosis (DVT) or pulmonary embolism (PE) at the time of SVT diagnosis. Unfortunately, the available data on this association are widely variable. Objectives To perform a systematic review and meta-analysis of the literature in order to evaluate the prevalence of concomitant DVT/PE in patients with SVT of the lower limbs. Methods Studies reporting on the presence of DVT/PE in SVT patients were systematically searched for in the PubMed, Web of Science, Scopus and EMBASE databases. The weighted mean prevalence (WMP) of DVT and PE was calculated by use of the random effect model. Results Twenty-one studies (4358 patients) evaluated the prevalence of DVT and 11 studies (2484 patients) evaluated the prevalence of PE in patients with SVT. The WMP of DVT at SVT diagnosis was 18.1% (95%CI: 13.9%, 23.3%) and the WMP of PE was 6.9% (95%CI: 3.9%, 11.8%). Heterogeneity among the studies was substantial. Selection of studies including outpatients only gave similar results (WMP of DVT, 18.2%, 95% CI 12.2-26.3%; and WMP of PE, 8.2%, 95% CI 3.3-18.9%). Younger age, female gender, recent trauma and pregnancy were inversely associated with the presence of DVT/PE in SVT patients. Conclusions The results of our large meta-analysis suggest that the prevalence of DVT and PE in patients presenting with SVT is not negligible. Screening for a major thromboembolic event may be worthwhile in some SVT patients, in order to allow adequate anticoagulant treatment to be planned. Other high-quality studies are warranted to confirm our findings.


Asunto(s)
Anticoagulantes/uso terapéutico , Extremidad Inferior/irrigación sanguínea , Embolia Pulmonar/diagnóstico , Tromboembolia Venosa/tratamiento farmacológico , Trombosis de la Vena/diagnóstico , Anciano , Recolección de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Embarazo , Complicaciones Cardiovasculares del Embarazo , Prevalencia , Análisis de Regresión , Factores de Riesgo
2.
Tech Coloproctol ; 17(6): 625-30, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23754346

RESUMEN

We carried out a systematic review of the literature to identify the association between the use of drain and the incidence of infections and recurrences after surgery. MEDLINE, SCOPUS and ISI databases were searched up to September 2012. The two outcomes of this meta-analysis were wound infection and recurrence. Postoperative wound infection occurred in 50 of the 604 (8.28 %) patients who underwent drainage and in 68 of the 598 (11.4 %) patients who did not, with a resulting odds ratio (OR) of 0.71 (95 % CI: 0.48-1.03). Recurrence of pilonidal sinus occurred in 41 of the 604 (6.79 %) patients who underwent drainage and in 50 of the 598 (8.36 %) patients who did not, with a resulting OR of 0.80 (95 % CI: 0.52-1.23). The results suggest that, despite a trend toward a reduction in infectious complications and recurrence, drainage was not associated with a better outcome. However, because of the present literature's limitations, further studies are needed to address this issue.


Asunto(s)
Drenaje , Seno Pilonidal/cirugía , Infección de la Herida Quirúrgica/epidemiología , Humanos , Incidencia , Recurrencia , Técnicas de Cierre de Heridas
3.
Biochim Biophys Acta ; 1830(9): 4365-73, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23220699

RESUMEN

BACKGROUND: There is no doubt that future discoveries in the field of biochemistry will depend on the implementation of novel biosensing techniques, able to record biophysiological events with minimal biological interference. In this respect, organic electronics may represent an important new tool for the analysis of structures ranging from single molecules up to cellular events. Specifically, organic field-effect transistors (OFET) are potentially powerful devices for the real-time detection/transduction of bio-signals. Despite this interest, up to date, the experimental data useful to support the development of OFET-based biosensors are still few and, in particular, n-type (electron-transporting) devices, being fundamental to develop highly-performing circuits, have been scarcely investigated. METHODS: Here, films of N,N'-1H,1H-perfluorobutyldicyanoperylene-carboxydi-imide (PDIF-CN2) molecules, a recently-introduced and very promising n-type semiconductor, have been evaporated on glass and silicon dioxide substrates to test the biocompatibility of this compound and its capability to stay electrically-active even in liquid environments. RESULTS: We found that PDIF-CN2 transistors can work steadily in water for several hours. Biocompatibility tests, based on in-vitro cell cultivation, remark the need to functionalize the PDIF-CN2 hydrophobic surface by extra-coating layers (i.e. poly-l-lysine) to favor the growth of confluent cellular populations. CONCLUSIONS: Our experimental data demonstrate that PDIF-CN2 compound is an interesting organic semiconductor to develop electronic devices to be used in the biological field. GENERAL SIGNIFICANCE: This work contributes to define a possible strategy for the fabrication of low-cost and flexible biosensors, based on complex organic complementary metal-oxide-semiconductor (CMOS) circuitry including both p- (hole-transporting) and n-type transistors. This article is part of a Special Issue entitled Organic Bioelectronics-Novel Applications in Biomedicine.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/estadística & datos numéricos , Electrónica Médica/instrumentación , Electrónica Médica/métodos , Imidas/química , Perileno/análogos & derivados , Semiconductores , Transistores Electrónicos , Animales , Células CHO , Adhesión Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cricetinae , Ensayo de Materiales/métodos , Metales/química , Nitrilos/química , Óxidos/química , Perileno/química , Agua/química
4.
Eur Biophys J ; 41(2): 249-56, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22237602

RESUMEN

Impedance spectroscopy (IS) is a powerful technique for analysis of the complex electrical impedance of a large variety of biological systems, because it is sensitive both to surface phenomena and to changes of bulk properties. A simple and convenient method of analysis of cell properties by IS is described. An interdigitated electrodes configuration was used for the measurements; human epithelial cells were grown on the device to investigate the complex dielectric response as a function of frequency, in order to test the suitability of the device for use as a label-free biosensor. To test the ability of the device to detect channels in the cell membrane, the effect of drugs known to affect membrane integrity was also investigated. The frequency response of the admittance (i.e. the reciprocal of the impedance) can be well fitted by a model based on very simple assumptions about the cells coating the device surface and the current flow; from the calculations, membrane-specific capacitance and information about cell adhesion can be inferred. These preliminary efforts have shown that our configuration could lead to a label-free non-invasive technique for biosensing and cellular behavior monitoring which might prove useful in investigation of the basic properties of cells and the effect of drugs by estimation of some fundamental properties and modification of the electrical characteristics of the device.


Asunto(s)
Técnicas Biosensibles/métodos , Espectroscopía Dieléctrica/métodos , Integración de Sistemas , Técnicas Biosensibles/instrumentación , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Electrodos , Células HeLa , Humanos , Nistatina/farmacología , Octoxinol/farmacología
5.
Talanta ; 62(3): 523-30, 2004 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-18969327

RESUMEN

Beauvericin (BEA), a supercritical fluid extraction with supercritical carbon dioxide from maize was investigated. Extraction efficiencies under several different extraction conditions were examined. Pressure, temperature, extraction time, organic modifier and water matrix content (10%) were investigated. The best extraction conditions were at a temperature of 60 degrees C, 3200psi, for 30min static extraction time and methanol as modifier solvent. Extraction recovery of 36% without modifier by adding water to the matrix in the extraction vessel (reproducibility relative standard deviations (R.S.D.)=3-5%) were recorded. Extraction recovery of 76.9% with methanol as co-solvent (reproducibility R.S.D.=3-5%) was obtained. Data shows that SFE gives a lower BEA recovery compared to conventional extraction protocol with organic solvents while SFE with modifier and conventional extraction yields are comparable. BEA extract contents were determined by high pressure liquid chromatography (HPLC) with a diode array detector (DAD) at 205nm and BEA peak confirmed by LC-MS. Acetonitrile-water as mobile phase and column C-18 were both tested. Instrumental and analytical parameters were optimized in the range linear interval from 1 to 500mgkg(-1) and reached a detection limit of 2ng.

6.
J Agric Food Chem ; 48(10): 4723-7, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11052724

RESUMEN

The phytonutrient intake associated with tomato consumption depends also on cultivar and fruit ripening stage. This work associates the antioxidative ability, the level of carotenoids, and the amount of glycoalkaloids to the main carpometric characteristics of four different typologies of tomatoes: "cherry", "cluster", "elongated," and "salad". These typologies have different weights and shapes, and they are usually consumed in the Mediterranean area at different ripening stages. Results showed that the considered tomato typologies also differ in their antioxidative ability and their carotenoid and glycoalkaloid contents. Growing conditions are also important in determining fruit characteristics: the analysis of the same cultivar of cherry tomato produced under the influence of moderate salt stress showed increases in the lipophilic antioxidative ability and the amount of carotenoid, whereas the level of glycoalkaloid decreased.


Asunto(s)
Antioxidantes/análisis , Carotenoides/análisis , Solanum lycopersicum/química , Tomatina/análisis , Solanum lycopersicum/anatomía & histología , Solanum lycopersicum/crecimiento & desarrollo
7.
J Agric Food Chem ; 47(12): 5252-6, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10606604

RESUMEN

A new supercritical extraction methodology was applied to extract azadirachtin A (AZA-A) from neem seed kernels. Supercritical and liquid carbon dioxide (CO(2)) were used as extractive agents in a three-separation-stage supercritical pilot plant. Subcritical conditions were tested too. Comparisons were carried out by calculating the efficiency of the pilot plant with respect to the milligrams per kilogram of seeds (ms/mo) of AZA-A extracted. The most convenient extraction was gained using an ms/mo ratio of 119 rather than 64. For supercritical extraction, a separation of cuticular waxes from oil was set up in the pilot plant. HPLC and electrospray mass spectroscopy were used to monitor the yield of AZA-A extraction.


Asunto(s)
Insecticidas/aislamiento & purificación , Limoninas , Semillas/química , Árboles , Triterpenos/aislamiento & purificación , Animales , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas
8.
Anticancer Drug Des ; 12(7): 555-76, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9365502

RESUMEN

Two pyrazole analogs structurally related to the antitumor agents adozelesin and U-71,184 respectively were synthesized. By using a polymerase chain reaction approach, both compounds show selective binding to A + T rich sequences exactly as reference compound U-71,184. In in vitro assays, against L1210 cell lines, both derivatives showed cytotoxicity in the pM range, values comparable with the natural target compound (+)-CC-1065. The most active compound showed very high antitumor activity in mice implanted with L1210 cells (ILS% 363).


Asunto(s)
Antineoplásicos/química , Ácidos Ciclohexanocarboxílicos/química , Indoles/química , Pirazoles/síntesis química , Animales , Benzofuranos , Sitios de Unión , Ciclohexenos , Duocarmicinas , Leucemia L1210/patología , Espectroscopía de Resonancia Magnética , Ratones , Trasplante de Neoplasias , Reacción en Cadena de la Polimerasa , Pirazoles/metabolismo , Pirazoles/farmacología , Espectrofotometría Infrarroja
9.
Comput Appl Biosci ; 11(2): 167-71, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7620989

RESUMEN

We employed the Codonusage database to analyze the codon usage pattern in 31 organisms from all the main biological taxa. We tested the similarity in codon usage pattern between each organism and all the others by the Pearson linear correlation coefficient. The 465 values obtained were located in a 31 x 31 triangular matrix from which a correlation distance matrix was calculated. An evolutionary dendrogram was then constructed from these distances. The results showed a fair correlation between codon usage patterns and phylogenetic relationships, at least for organisms which diverged in rather recent times (end of Jurassic--beginning of Cretaceous).


Asunto(s)
Codón , Filogenia , Animales , Humanos , Microcomputadores , Especificidad de la Especie
10.
Ann Hum Biol ; 19(4): 371-85, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1616292

RESUMEN

The distribution of surnames in the population of the town of Ferrara, as it existed in the memory banks of the Municipality Computer in June 1990, was studied by sex, age and place of birth of residents. Random isonymy was studied separately in persons born before 1901, and in persons born in the nine decades thereafter, ending with the period 1981-90. Isonymy was higher in the older age groups studied. Also other indicators of the abundance of surnames in the distribution, the common ecological indexes derived from entropy, were calculated and compared between age groups. It was found that redundancy, as isonymy, is larger in older age classes than in younger classes. Surname effective number was defined as the inverse of isonymy corrected for sample size, and it was observed that it is practically identical with Fisher's alpha. It was then possible to separate random isonymy into two components, so that for sample size N its formulation becomes Ir = 1/alpha + 1/N It was found that in Ferrara alpha increased significantly in time, indicating enrichment of surnames in the population in the century 1890-1990.


Asunto(s)
Bases de Datos Factuales/tendencias , Genética de Población/historia , Nombres , Factores de Edad , Emigración e Inmigración , Femenino , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Italia , Masculino , Factores Sexuales , Factores de Tiempo
11.
Mutat Res ; 267(2): 173-82, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1376419

RESUMEN

The statistical methods for the analysis of mutagenicity and carcinogenicity underwent considerable theoretical-practical development following the need for assessing the mutagenic and carcinogenic potential of substances. Antimutagenicity is investigated through the analysis of respondents in dose-response assays, when two different molecules are administered separately and as a mixture to a respondent system. When the number of respondent units is high, and doses are orthogonal, it is possible to apply simple models such as analysis of variance. This is not always possible or common, and alternative approaches have been developed, based on multiple regression and on tables of proportions. In this work, some of the most frequently used methods for the assessment of joint responses are reviewed, particularly those based on multiple regression, such as the method of Shaeffer et al. and the method of Hass et al. In order to illustrate these methods, joint responses of perylene and cyclopentapyrene, of N-acetylcysteine and dinitropyrene, and of N-acetylcysteine and extracts from diesel exhausts were analyzed. An antagonistic effect of perylene on the action of CPP was detected by the algorithm of Shaeffer et al. The effect is not multiplicative, i.e., it is not proportional to the product of doses. The antimutagenic effect of N-acetylcysteine on dinitropyrene is multiplicative, as detected by the method of Hass et al. The latter reveals that the inhibition by N-acetylcysteine on the mutagenic effect of extracts from diesel exhausts is also multiplicative.


Asunto(s)
Antimutagênicos/farmacología , Acetilcisteína/farmacología , Interacciones Farmacológicas , Mutágenos/toxicidad , Perileno/farmacología , Pirenos/toxicidad , Emisiones de Vehículos/toxicidad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...