Organochlorine residues in fishes from two rivers in Cantabria, Spain: implications for a program of otter (Lutra lutra) reintroduction.
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Animals↗
Biomedical subjects
M Rodríguez
Publications and source records attributed to M Rodríguez.
Involvement of adenovirus in clinical mononucleosis-like syndromes in young children.
Although Epstein-Barr virus (EBV) commonly causes infectious mononucleosis (IM) or IM-like syndromes, other agents can be implicated. In this study, viral and parasitic screening was performed to determine the etiological agent of pediatric IM-like syndromes in 38 children. Adenovirus was the agent most frequently detected (47.3%), followed by EBV (31.5%) and cytomegalovirus (2.6%). Although the statistically significant difference between viral detection rates observed in patients who fulfilled clinical and hematological criteria and detection rates in those who presented clinical symptoms only (91.6% vs. 64.3%) indicates that hematological abnormalities are common in viral IM-like syndromes, the existence of syndromes of viral etiology without hematological criteria cannot be discarded. A further analysis showed an absence of lymphocytosis in adenovirus infections as well as a low number (14.3%) of EBV infections associated with increased neutrophils. These data suggest the usefulness of appropriate virological techniques for the detection of adenovirus in pediatric IM-like syndromes.
Adenovirus Infections, Human↗
Patency and structural changes in cryopreserved arterial grafts used as vessel substitutes in the rat.
OBJECTIVE: To evaluate the patency and structural changes that occur in the short- and mid-term when cryopreserved syngenic arterial grafts are implanted in an experimental animal model. MATERIAL AND METHODS: Segments of iliac artery from the Spraque-Dawley rat were cryopreserved in a biological freezer according a controlled, computerized freezing protocol whereby the specimens are cooled at a rate of 1 degrees C/min. After storage at -145 degrees C in liquid N2 vapor for 30 days, the cryografts were slowly thawed. These vessels were grafted to the common iliac artery in syngenic animals. The following study groups were established: group I (GI), non-implanted cryografts; group II (GII), autografts; and group III (GIII), cryoisografts. The control group (CG) was comprised of fresh iliac arteries. The animals were sacrificed 14, 30, or 90 days post-surgery. At each of these follow-up times, graft specimens were morphologically evaluated by light and scanning and transmission electron microscopy and immunolabeling of endothelial cells (vWf). Cell damage attributed to the cryopreservation or grafting process was also determined. RESULTS: At the time of sacrifice, graft patency was 100% for the autografts, while 26.6% of the cryoisografts showed fully occlusive thrombosis. Among other complications, two pseudoaneurysms were detected. After cryopreservation, the grafts (GI) showed patches of endothelial denudation and good cellularity of the medial layer. The intimal hyperplasia observed in autografts implanted for 14 days (GII) was significantly delayed until day 30 when the graft was cryopreserved (GIII). Cryoisografts showed general thinning of the arterial wall and degeneration accompanied by medial layer cell loss. These grafts showed most cell damage at 90 days post-implant. Expression of the vWf in all specimens showing intimal hyperplasia was confined to the outermost graft layer. CONCLUSIONS: Cryopreservation modified the reparative response of the grafts. Owing to faster degeneration of the medial layer and a delay in the appearance of intimal hyperplasia, arterial wall thickness was reduced relative to that of the non-cryopreserved autografts. This thinning, at least in the short-term (90 days), does not seem to give rise to aneurysms owing to the generation of a neointima that stabilizes the vessel wall.
Animals↗
Development of a rat model of spinal cord injury and cellular transplantation.
BACKGROUND AND PURPOSE: Intravenously or intraspinally delivered human umbilical cord blood (UCB) cells and mesenchymal stem cells have been previously shown to improve the functional recovery of spinal cord-injured rats. Obtaining an animal model in the laboratory setting is critical for the development of experimental therapies. We have established a rat model of spinal cord injury (SCI) with basic histological and functional evaluations, ready to use for cell transplantation experiments. METHODS: In the first phase 10 Sprague-Dawley (SD) rats were used to standardize the laminectomy at D9-D10 without secondary lesions. In a second phase, 28 SD rats were laminectomized and injured at D9 by spinal cord compression for 3 to 5 seconds with an aneurysmal clip. Open-field behavior was assessed at days 2 and 7 postoperatively, and weekly until their sacrifice, using the Basso, Beattie, and Bresnahan locomotor rating scale. Two weeks postinjury, 14 immunosuppressed rats received a double intraspinal cell transplant of previously frozen UCB mononuclear cells (MNCs). Using a Hamilton syringe, 2.5 x 10(5) unlabelled MNCs in 10 microL medium were transplanted, rostrally and caudally to the lesion site. Rats were sacrificed at 4 weeks posttransplant by transcardial perfusion with 4% paraformaldehyde, and spinal cords were dissected and further fixated for histological analysis. RESULTS: No wound infections were observed. Thirteen rats developed urinary tract infections and two animals showed autophagia grade 3. We observed a common spontaneous mobility improvement until a certain limit, depending on the degree of lesion and intrinsic characteristics of the animal. CONCLUSIONS: An animal model of SCI has been established. Critical parameters in the survival and correct functional analysis are continuous animal care postinjury, urinary tract infections, autophagia, and weight loss. In addition, electrophysiological measures might be necessary to properly assess functional modifications.
Animals↗
Positron emission tomography use in the diagnosis and follow up of Takayasu's arteritis.
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Adult↗
Muscle-derived stem cells in tissue engineering: defining cell properties suitable for construct design.
The terms construct or tissue equivalent refer to neotissue produced by tissue engineering techniques. The elements forming the construct are scaffolds on which cells are "recreated" to form an engineered-tissue sensitive to certain cell signals. The ability of the cells to expand and differentiate on the scaffold is determined by properties such as fixation, adhesion, proliferation and migration. Among the cell types that seem to be most promising for designing constructs are tissue-residing, or adult, stem cells, which show two main features: a capacity to differentiate into many cell lineages and the power of self-renewal. These features make them good candidates for cell replacement therapies. Here, we report the identification, isolation and culture of muscle stem cells aimed at establishing the ideal culture in terms of defining when the cultured cell population would show optimal characteristics for transfer to the scaffold to obtain a particular construct. Stem cells harvested from the dorsal muscle of white New Zealand rabbits were cultured in vitro and characterized 5 to 14 days after the start of culture. Fibroblasts obtained from the same experimental animal served as controls. The stem cells were examined by light and scanning electron microscopy. For stem cell identification, we used the antibodies anti-m-cadherin, anti-CD34 and anti-Myf-5. The markers of muscle differentiation used were: anti-vimentin, anti-alpha-actin, anti-desmin and anti-myosin. The expression profiles of the different markers of muscle differentiation and TGFbeta1 in the cell cultures were confirmed by Western blotting. Proliferation rates were determined by monitoring tritiated thymidine incorporation. The thymidine incorporation rate was substantially higher for the population of undifferentiated cells than for control fibroblasts obtained from the same animal. During the first five days of culture, most cells were negative for all the markers examined, with the exception of m-cadherin, CD34 and Myf-5, although discrete signs of vimentin expression started to emerge. After 14 days of culture, the adult stem cells showed vimentin (94.2%) and desmin (33.8%) expression yet scarce labeling for myosin (16.2%) and alpha-actin (8.3%). Control fibroblasts showed intense labeling for vimentin (99.3%) and alpha-actin (62.2%), while less than 2% of the population expressed myosin (0.9%) and desmin (1.6%). After two weeks of culture, muscle-derived stem cells show good proliferative and adhesion properties as they initiate differentiation. These conditions seem ideal for obtaining the desired construct.
Actins↗
Pairing gap and in-gap excitations in trapped fermionic superfluids.
We consider trapped atomic Fermi gases with Feshbach-resonance enhanced interactions in pseudogap and superfluid temperatures. We calculate the spectrum of radio-frequency (or laser) excitations for transitions that transfer atoms out of the superfluid state. The spectrum displays the pairing gap and also the contribution of unpaired atoms, that is, in-gap excitations. The results support the conclusion that a superfluid, in which pairing is a manybody effect, was observed in recent experiments on radio-frequency spectroscopy of the pairing gap.
Journal Article↗
Signatures of superfluidity for Feshbach-resonant Fermi gases.
We consider atomic Fermi gases where Feshbach resonances can be used to study the whole BCS-Bose-Einstein condensate crossover. We show how a probing field transferring atoms out of the superfluid can be used to detect the onset of the superfluid transition in the high-T(c) and BCS regimes. The number of transferred atoms, as a function of the energy given by the probing field, peaks at the gap energy. The shape of the peak is asymmetric due to the single particle excitation gap. Since the excitation gap also includes a pseudogap contribution, the asymmetry alone is not a signature of superfluidity. The incoherent nature of the noncondensed pairs leads to broadening of the peak. The broadening decays below the critical temperature, causing a drastic increase in the asymmetry. This provides a signature of the transition.
Journal Article↗
Radioecological software package: an interactive computational system to simulate the behaviour of radionuclides in semi-natural environments.
RSP (Radioecological Software Package) is an interactive support system that simulates the behaviour of radionuclides in semi-natural environments and the consequences on the population in terms of the external exposure. RSP consists of three modules: the first one, soil mobility, simulates the vertical transport of radionuclide in soil using the mathematical model RABES. The second module, soil -to-plant transfer, simulates the radionuclide soil-to-plant transfer factor reported in the literature. Soil properties, vegetation types and environmental conditions are taken into consideration in the simulation process. In the third module, dose assessment, the dose-rate factor in air at a height of 1 m above ground can be calculated for sources distributed in a slab of finite thickness dn sources which are exponentially distributed with depth. The calculations are performed using DAGES Model, a Monte Carlo algorithm developed to simulated the photon transport for the soil/air configuration. A free copy of RSP can be downloaded from the website: http://imasl-apat.unsl.edu.ar.
Air Pollutants, Radioactive↗
Function of cryopreserved pig aortas.
OBJECTIVES: This paper analyzes the influence of storage in the gas phase or liquid phase on grafts, together with the thawing method (15 degrees C/min or 100 degrees C/min) on the postthawing activity of pig cryopreserved arterial grafts (aortas). MATERIALS AND METHODS: Obtainment of arterial grafts (aortas) was from pigs with an ischemic time not greater than 2 h. Each aorta was divided into five fragments and assigned randomly to one control group of fresh aorta and four groups of cryopreserved aortas: group 1: gas phase/slow thawing; group 2: gas phase/rapid thawing; group 3: liquid phase/slow thawing; and group 4: liquid phase/rapid thawing. After the incubation in antibiotic solution, the cryopreservation in RPMI medium +10% DMSO was carried out and the level of cooling used was a reduction of 1 degrees C/min. The contraction and relaxation responses of the fresh and frozen/thawed arteries were carried out in organ baths. RESULTS: After thawing, the sensitivity to various agonists and maximal responses to the endothelium-dependent and independent relaxant agents were decreased. The maximal responses to the tested vasoconstrictors (KCl and noradrenaline) were, respectively, 13% and 24% of the responses obtained in unfrozen aortas. The endothelium-independent relaxant responses to sodium nitroprusside (SNP) were reduced and important reductions of the endothelium-dependent relaxant responses to acetylcholine were produced. CONCLUSIONS: The cryopreservation of pig aortas under the conditions used in this study led to a decrease in the contractility of the pig aortas, as well as a decrease in the endothelium-independent relaxant responses. On the other hand, no apparent preservation of the endothelium-dependent relaxant responses was observed.
Animals↗
Application of the Max-Lloyd quantizer for ECG compression in diving mammals.
This article presents a practical implementation of an ECG compression algorithm using a Max-Lloyd quantizer, to optimize the low resources of an ECG acquisition and transmission system (telemetry system) for dolphins and human divers. The algorithm scheme is based on a first-order differential pulse code modulation (DPCM) and uses a Max-Lloyd quantizer to code the difference between the current and predicted samples. The use of the non-uniform quantizer instead of a uniform quantizer improves the percent root mean-square difference (PRD), thereby producing a low distortion in the reconstructed signals. Due to its low computational complexity, the compression process can be accomplished on-line during the ECG acquisition process.
Algorithms↗
Production and biochemical characterization of the recombinant Boophilus microplus Bm95 antigen from Pichia pastoris.
The new antigen Bm95 from the cattle tick Boophilus microplus was recently isolated, cloned and expressed in the methylotrophic yeast Pichia pastoris. The recombinant protein has shown to induce protection in cattle against infestations of B. microplus under controlled and production conditions. In this paper we report the production and large-scale purification of the Bm95 protein, following a simple and cost-effective process. The antigen was obtained highly aggregated, forming particles ranging from 26 to 30 nm and with purity higher than 80%. The process yield was 0.55 g of pure Bm95 protein per liter of culture. The 98% of the primary structure of the recombinant protein was verified by mass spectrometry. Three amino acid changes in comparison with the sequence deduced from cDNA were detected by LC-MS/MS. The antigen was also obtained N-glycosylated, as previously reported for heterologous protein expression in P. pastoris.
Amino Acid Sequence↗
[Changing epidemiology of smoking: Barcelona, 2000-2001].
CONTEXT: In recent years various initiatives of prevention and social changes have been carried out that should have an effect on epidemiology of smoking in our area. Their real effect is little known, however, because of methodological changes in the existing population surveys. In this work the data on smoking in the last city of Barcelona health survey (ESBA 2000-01) are analyzed, with reference to the cumulative information obtained along 18 years from the first survey in 1983. METHOD: ESBA 2000-01 is an interview health survey carried out on a weighted sample with 10,030 people. Data relative to tobacco use are showed for people 15-year-old or older included in the survey, stratified by age, sex, and class. Consumption context variables are also showed, and the tobacco consumption quitting among people who have smoked is analyzed. RESULTS: The proportion of daily smokers in the population over 14 years of age is 29 %, while that of former smokers is 21 % and 2.2 % in this population are occasional smokers. The prevalence is maximum in the 35-44 year-old group, and the prevalence is reduced drastically after this age. Stratified analysis by age, sex, and occupational category shows interesting differences among daily smokers. A strong gradient is observed according to occupational category in males. The situation is more complex in women. The typical smoker began when 17-year-old, and now consumes 16 cigarettes a day. Consumption is somewhat higher in males and is maximum in the 35-44 year-old group. Two-third of the smokers (65.7 %) want to quit smoking and more than one third (36 %) has attempted it along the last year. Almost half of smokers (48.1 %) have received advice to quit smoking from their physician. One of every four (24.9 %) smokers has been warned for smoking in some places. Almost half smokers are the only smoker in their home, and barely a third are the only smokers at work. The proportion of quitting increases with age in both sexes, and nowadays the differences in the probability of quitting smoking are few when the data are stratified by age groups. CONCLUSIONS: These results show the changing pattern of tobacco epidemiology in Barcelona: smoking is no longer the main behavior in no age and sex group, and the only social group in which more than half of its members smoke are 25-44 year-old not qualified worker males. This situation has occurred because of two processes: an important proportion of early quitting (demonstrated even in young adults) and a decrease in the beginning of the habit. Real differences are not observed between males and females with regard to the probability of quitting smoking. These data correct recent estimates that could be influenced by methodological changes in the instruments used.
Adolescent↗
Effect of milking pipeline height on machine milking efficiency and milk quality in sheep.
This experiment studied the effect of milking pipeline height (mid- vs. low-level milking system) on milking efficiency and milk composition. The experiment was of 8 wk duration: 2 wk preexperimental period and 6 wk experimental, in crossover design (2 x 2). Ewes were milked in a 2 x 12 milking parlor with 2 milking pipelines set at a milking vacuum of 36 kPa with a pulsation rate of 180 cycle/min and ratio of 50%. Height of the milkline had no effect on yield of milk at the time of milking, yield after stripping, milk composition, SCC, and number of teatcup fall-offs. Nor did milkline height have any effect on milk lipolysis or on the distribution of fatty acids. The level of free fatty acids was higher in evening than in morning milk (60.5 vs. 25.6 mg/L). Likewise, the increase in the degree of lipolysis between the receiver (40.4 mg/L) and the refrigeration tank (45.8 mg/L) underlines the importance of the milk delivery line design. The parameters (time and flow rate) that define the first peak in the milk emission kinetics were statistically different between lines, so care must be taken when comparing milk emission curves from both types of pipeline.
Animals↗
Characterization of molds from dry-cured meat products and their metabolites by micellar electrokinetic capillary electrophoresis and random amplified polymorphic DNA PCR.
Molds are common contaminants of dry-cured meat products in which mycotoxins could be synthesized if stored under favorable conditions. Thus, efficient and accurate characterization of the toxigenic molds from dry-cured meat products is necessary. A micellar electrokinetic capillary chromatography (MECC) method was tested to analyze secondary metabolites produced by 20 mold strains commonly found in dry-cured meat products. In addition, their random amplified polymorphic DNA (RAPD) genotypes were determined by using a PCR method. Although peak profiles of the secondary metabolites differed among mold strains of different species, they were similar in the same species. MECC analysis showed that 10 of the 20 molds tested produced mycotoxins, including patulin, penicillic acid, cyclopiazonic acid, mycophenolic acid, aflatoxin B1, sterigmatocystin, and griseofulvin. The RAPD analysis yielded a different pattern for each of the mold species tested. However, strains of the same species showed similar RAPD profiles. A high correlation between RAPD analysis and MECC was observed, since strains of the same species that showed similar RAPD patterns had similar profiles of secondary metabolites. RAPD patterns with primer GO2 and MECC profiles, either singly or combined, could be of great interest to distinguish toxigenic from nontoxigenic molds in dry-cured meat products.
Chromatography, Micellar Electrokinetic Capillary↗
The need for specialized adolescence units.
Adolescence is the period of life of transition from childhood to adulthood; it includes not only sexual maturation but also physical and psychological maturation. The chronological age when this transition occurs is imprecise and not exactly defined. There are specific diseases that appear during this period of life that deserve specialized medical care. This article deals with the need to create specialized adolescence units with the direct participation of pediatricians. The transition through adolescence into adulthood is complicated by physical, psychological and social issues, and the transfer of adolescent patients to adult departments should be done gradually. There is a need for consensus guidelines about this issue.
Adolescent↗
[Peripartum myocardiopathy in a woman with acquired immunodeficiency syndrome].
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Adult↗
[Vascular calcification mechanisms in uremia].
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Calcinosis↗