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Biomedical subjects

F Cabello

Publications and source records attributed to F Cabello.

At least 19 recordsLinked to original sources
PubMed2006

Multiple origins of cultivated grapevine (Vitis vinifera L. ssp. sativa) based on chloroplast DNA polymorphisms.

The domestication of the Eurasian grape (Vitis vinifera ssp. sativa) from its wild ancestor (Vitis vinifera ssp. sylvestris) has long been claimed to have occurred in Transcaucasia where its greatest genetic diversity is found and where very early archaeological evidence, including grape pips and artefacts of a 'wine culture', have been excavated. Whether from Transcaucasia or the nearby Taurus or Zagros Mountains, it is hypothesized that this wine culture spread southwards and eventually westwards around the Mediterranean basin, together with the transplantation of cultivated grape cuttings. However, the existence of morphological differentiation between cultivars from eastern and western ends of the modern distribution of the Eurasian grape suggests the existence of different genetic contribution from local sylvestris populations or multilocal selection and domestication of sylvestris genotypes. To tackle this issue, we analysed chlorotype variation and distribution in 1201 samples of sylvestris and sativa genotypes from the whole area of the species' distribution and studied their genetic relationships. The results suggest the existence of at least two important origins for the cultivated germplasm, one in the Near East and another in the western Mediterranean region, the latter of which gave rise to many of the current Western European cultivars. Indeed, over 70% of the Iberian Peninsula cultivars display chlorotypes that are only compatible with their having derived from western sylvestris populations.

DNA, Chloroplast↗
PubMed2004

The MELISSA pilot plant facility as as integration test-bed for advanced life support systems.

The different advances in the Micro Ecological Life Support System Alternative project (MELISSA), fostered and coordinated by the European Space Agency, as well as in other associated technologies, are integrated and demonstrated in the MELISSA Pilot Plant laboratory. During the first period of operation, the definition of the different compartments at an individual basis has been achieved, and the complete facility is being re-designed to face a new period of integration of all these compartments. The final objective is to demonstrate the potentiality of biological systems such as MELISSA as life support systems. The facility will also serve as a test bed to study the robustness and stability of the continuous operation of a complex biological system. This includes testing of the associated instrumentation and control for a safe operation, characterization of the chemical and microbial safety of the system, as well as tracking the genetic stability of the microbial strains used. The new period is envisaged as a contribution to the further development of more complete biological life support systems for long-term manned missions, that should be better defined from the knowledge to be gained from this integration phase. This contribution summarizes the current status of the Pilot Plant and the planned steps for the new period.

Biodegradation, Environmental↗
PubMed2003

Characterization of Spanish grapevine cultivar diversity using sequence-tagged microsatellite site markers.

A broad germplasm bank collection containing most of the autochthonous Spanish grapevine cultivars was analyzed using six sequence-tagged microsatellite site (STMS) loci: VVS2, VVMD5, VVMD7, ssrVrZAG47, ssrVrZAG62, and ssrVrZAG79. The number of alleles obtained ranged from 9 in ssrVrZAG47 to 13 in VVS2, and the observed genotypes per locus varied between 24 (ssrVrZAG47) and 41 (VVSS2). A total of 57 unique genotypes were obtained considering all 6 loci, and 40 varieties presented at least 1 of these specific genotypes. The genotypic combinations for the 6 loci have generated 163 different profiles in the 176 cultivars. Ten pairs of accessions and one group of four Garnacha's cultivars can not be differentiated. The observed heterozygosity varied between 75.6 (VVMD7) and 90.9% (VVMD5), without significant differences from the expected values for any loci. The VVMD5 locus was the most informative, and also showed the highest discrimination power. The cumulative discrimination power for all six loci was practically 1; however, in fact, these STMS loci have differentiated only about 93% of the accessions, probably owing to high relatedness of the plant material. Usefulness of this STMS set for characterization of a Spanish grapevine collection is emphasized, as well as the elaboration of databases with these molecular markers.

Gene Frequency↗
PubMed2002

MELISSA: a loop of interconnected bioreactors to develop life support in space.

The development of a loop of interconnected continuous bioreactors, aimed to provide life support in space, is reported. The complete loop concept consists of four bioreactors and one higher plant compartment. For its realization the continuous and controlled operation of the bioreactors is characterized, up to the pilot scale level, first for each individual reactor, second for the interconnected reactor operation. The results obtained with the two more advanced bioreactors in the Micro Ecological Life Support System Alternative (MELISSA) loop are described more specifically. These reactors consist of a packed-bed reactor working with an immobilized co-culture of Nitrosomonas and Nitrobacter cells, and an external loop gas-lift photobioreactor for the culture of the cyanobacteria Spirulina platensis. Their individual operation for long duration runs has been achieved and characterized, and their interconnected operation at pilot scale is reported.

Bioreactors↗
PubMed2001

Value of high-performance liquid chromatographic analysis of anthocyanins in the differentiation of red grape cultivars and red wines made from them.

A HPLC method that allows the separation of several anthocyanins present in red grapes and red wines, using a linear gradient of acetonitrile in water at pH 1.3, using perchloric acid as an acid modifier, is described. Data clearly show that the anthocyanins profile of red grapes may be complex, but quite different for each cultivar studied. Thus, those molecules may be used as chemotaxonomic markers for classifying red grape cultivars. However, the anthocyanin profile of red wines clearly differs from that presented by grapes employed in making it, because red wine contains a higher relative amount of malvidin-3-O-glucoside than grapes, and the relative amount of other anthocyanins in wines is usually lower than in grapes. Therefore, the use of anthocyanins present in wines to determine the grape cultivar used for winemaking needs a careful evaluation of the influence of different technological procedures on the anthocyanins fingerprint.

Anthocyanins↗
PubMed1999

Assessment of the native electrophoretic analysis of total grape must proteins for the characterization of Vitis vinifera L. cultivars.

The findings of an ampelographic analysis of vines belonging to a Germoplasm Bank were compared to the results of native electrophoresis of the total proteins in their musts. Cluster analysis of the data from the morphological description produced correct groupings, in terms of variety, for all samples. When cluster analysis was performed on the electrophoretic data, 10 of the 11 musts studied were grouped correctly. Electrophoresis was also performed on 30 musts made from a mixture of grapes from large vineyards. In the cluster analysis of the electrophoretic data on the proteins of the 41 musts studied, all the musts are grouped correctly in terms of variety. Electrophoretic analysis of proteins is a simple technique that can be used routinely, provides complementary information to morphological analysis for varietal characterization of vines, and in the majority of cases, makes it possible to ascertain the grape variety from which musts originate.

Electrophoresis, Polyacrylamide Gel↗
PubMed1997

Antibiotic-resistant Salmonella typhi from two outbreaks: few ribotypes and IS200 types harbor Inc HI1 plasmids.

To investigate factors that could be involved in the emergence of antibiotic resistant S. typhi, we characterized R plasmids and antibiotic resistant S. typhi strains from two outbreaks of typhoid in Peru and Chile. Differences in the Inc HI1 plasmids of Peruvian and Chilean strains were identified by conjugation and incompatibility studies and plasmid DNA characterization. Antibiotic-resistant S. typhi harboring Inc HI1 plasmids belonged to a reduced number of Pst1 and Cla1 ribotypes and IS200 types, in contrast to the high genetic diversity found among epidemic antibiotic-susceptible S. typhi. The low diversity of antibiotic-resistant S. typhi suggests that they may express properties that are related to both their ability to harbor Inc HI1 R plasmids and to disseminate.

Bacteriophage Typing↗
PubMed1997

[Emergent diseases: old and new diseases. Etiological and climatic aspects. Socioeconomic and cultural influences].

During recent years the world has experienced the reemergence of old communicable diseases and the emergence of new ones caused by novel pathogens such as the HIV virus and Borrelia burgdorferi. The problem consists mostly in the reemergence of old diseases but specially in industrialized countries new pathogens have also been described. Although the emergence of these infections in rare instances is due to genetic changes of pathogens to more virulent forms, most commonly they are due to changes in the environment and the host. Rapidly deteriorating living standards, disintegration of sanitation and public health infrastructure, cultural changes, migration and variations in behavior are some of the factors involved in the worldwide increase of infectious diseases. The degradation of natural habitats including forests and marine niches accompanied by climatic changes, are also playing an increasing role in the detrimental evolution of these diseases. The global emergence of these diseases calls into question the doctrine of epidemiological transition and directs us to scrutinize the paradigm that bases the prevention of these diseases solely on vaccination. The current situation also highlights the limitations of classical epidemiology in dealing with unexpected problems, and strongly suggests that this discipline should incorporate into its analysis findings from other fields, including ecological, climatological, and economical information. As most of the negative social and economical developments that impinge on the detrimental evolution of these diseases are increasing world-wide, it can be predicted that the problems posed by these infections will continue and perhaps worsen in the near future.

Chile↗
PubMed1997

[Typhoid fever in Chile 1977-1990: an emergent disease].

The emergence of old and new communicable diseases is becoming an important public health problem in industrialized and developing countries worldwide. Chile experienced, at the end of the seventies and during the eighties, epidemics of several emergent communicable infectious diseases whose relevance as public health problems had steadily decreased in the previous 25 years. The most striking of these epidemics was a severe outbreak of typhoid fever that lasted at least 10 years. The majority of the cases occurred in the urban setting of Santiago. Several investigators suggested, in light of apparently good sanitation statistics, that factors responsible for this outbreak of typhoid were an increase in the number of chronic carriers of Salmonella typhi, the lack of microbiological food controls and the consumption of vegetables irrigated with waste water contaminated with S typhi. However, there is a dearth of epidemiological information and field work confirming the role of these factors in this typhoid outbreak. Moreover, the sudden, massive and urban characteristics of this epidemic, coupled to contemporary information regarding shortcomings on the preparation of drinking water and on decreased availability of drinking water to the population in Santiago regardless of good sanitation statistics, suggest that this outbreak may have been partially waterborne. The beginning of this typhoid outbreak also coincided with increased rain fall, with rapidly deteriorating economic and social conditions manifested in high rates of unemployment, and with decreased government investment on social services, including sanitation and health. All these factors are known to influence the epidemiology of typhoid and other emergent diseases worldwide.

Chile↗
PubMed1994

Role of cardiopulmonary exercise testing and the criteria used to determine disability in patients with severe chronic obstructive pulmonary disease.

The aim of this study was to evaluate the precision and variability with which resting pulmonary function tests (resting PFTs) can be used to predict the capacity in exercise, and the usefulness of the different measurements of pulmonary function in the evaluation of impairment/disability in patients with chronic obstructive pulmonary disease (COPD). We studied 78 patients with stabilized COPD (FEV1 45.1 +/- 17.1%). Of these, 39 suffered severe impairment according to the resting PFTs. Both the group with severe impairment (maximal oxygen consumption [VO2,max]: 16.22 +/- 5 ml/kg/min; maximal minute ventilation [VEmax]: 31.87 +/- 7.1 L/min; maximal heart rate [HRmax]: 133.8 +/- 10.9 beats/min) and the group with nonsevere impairment according to the resting PFTs (VO2max: 22.55 +/- 7.9 ml/kg/min; VEmax: 42.11 +/- 10.9 L/min; HRmax: 138 +/- 13.7 beats/min) showed ventilatory limitation during exercise. FEV1 was the most prevalent criterion for the determination of severe impairment (FEV1 < 40%), and was the variable best correlated to VO2max (r = 0.52 with VO2max as absolute value and r = 0.54 with VO2max expressed as a percentage of the reference value), but the resting PFTs were not predictive of exercise performance including patients with severe COPD. Evaluation of working capacity (based on VO2max) revealed a significant number of inaccurate predictions among the results of the resting PFTs. Sensitivity and specificity analysis were used to compare the different criteria used to evaluate the severity of disability. They reveal that the classification will be different according to the criteria used.(ABSTRACT TRUNCATED AT 250 WORDS)

Disability Evaluation↗
PubMed1993

Lipopolysaccharide-independent radioimmunoprecipitation and identification of structural and in vivo induced immunogenic surface proteins of Salmonella typhi in typhoid fever.

The humoral response to Salmonella typhi is important for protective immunity against typhoid fever, as indicated by the protection obtained with killed cell vaccines and component vaccines (outer membrane proteins, Vi antigen) in animals and human beings. Nonetheless, analysis and interpretation of host humoral immune response to S. typhi surface antigens have been difficult because of the complex structure of the S. typhi envelope and the lack of purified reagents for detection of immune response to individual surface components. Normal and convalescent human sera from typhoid fever patients were absorbed with S. typhi lipopolysaccharide. These sera were used in radioimmunoprecipitation assays of whole S. typhi cells and S. typhi membranes labelled with either 125I or 35S-methionine. This strategy has permitted the unequivocal identification of a humoral immune response to structural and in vivo induced outer membrane proteins of S. typhi. In this manner, we have identified the porins, lipoprotein, the iron-starvation-induced proteins, and three proteins of 30, 18.5 and 15 kDa as surface-exposed immunogens of S. typhi in patients with typhoid fever. These studies suggest that further experimental work is needed to characterize the relevance of both anti-S. typhi outer membrane protein and antilipopolysaccharide antibodies in recovery from S. typhi infections and protective immunity.

Antibodies, Bacterial↗
PubMed1991

Antiborrelial activity of serum from rats injected with the Lyme disease spirochete.

The functional properties of humoral factors generated in rats immunized against Borrelia burgdorferi were investigated. After Lewis strain rats were injected intraperitoneally with live B. burgdorferi or in the footpad with dead borreliae incorporated in complete Freund's adjuvant, they produced high-titered antisera. At a dilution of less than or equal to 1:10, sera from immunized or infected rats but not control sera inhibited growth of B. burgdorferi in vitro. Neutralization of growth of three different strains of B. burgdorferi by posttreatment sera was dose-dependent and was detected equally well by direct microscopic counts or by measuring incorporation of tritiated adenine into newly synthesized nucleic acids. These findings provide direct evidence that infection or immunization with the Lyme disease spirochete induces the formation of serum factors capable of preventing the growth of B. burgdorferi in vitro.

Animals↗
PubMed1991

Use of plasmid profiles in the investigation of a patient with Helicobacter pylori infection and peptic ulcer disease.

Plasmids may effect bacterial virulence and antibiotic resistance, and serve as epidemiologic markers. In this study, plasmid DNA profiles of serial isolates of Helicobacter pylori showed persistence of an identical strain of this organism in a patient with duodenal ulcer disease. Three control strains of H. pylori isolated from other patients contained plasmids different from each other and from that of the original patient; two of these strains had two plasmids each. These data have important implications for further study of the epidemiology and pathogenesis of H. pylori-related diseases.

DNA, Bacterial↗
PubMed1989

ColV increases the virulence of Escherichia coli K1 strains in animal models of neonatal meningitis and urinary infection.

Isogenic Escherichia coli strains, differing in their expression of K1 antigen and ColV plasmid, were studied for their ability to produce disease. Newborn rats were used to test the ability of these strains to colonize the intestine and to produce bacteremia and meningitis; adult rats were used to test their ability to produce urinary tract infection. Colonization of intestine and bladder by K1+ ColV+ E. coli was associated with rapid induction of bacteremia and higher mortalities compared with colonization with K1+ ColV- strains. These findings suggest that the ColV plasmid could play a role in the pathogenesis of human infections.

Animals↗