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Biomedical subjects

A Aguilar

Publications and source records attributed to A Aguilar.

At least 37 records · Page 2Linked to original sources
PubMed2004

Levels of organochlorine compounds in spotted dolphins from the Coiba archipelago, Panama.

Blubber and skin samples from 63 spotted dolphins (Stenella attenuata) (18 males, 40 females and 5 of unknown sex) were collected by biopsy techniques in the waters of the Coiba archipelago. Blubber was analyzed for organochlorine compounds and skin for gender determination. Mean levels of HCB (hexachlorobenzene), tPCB (polychlorinated biphenyls) and tDDT (dichlorodiphenyltrichloroethane) were 0.064, 2.30 and 6.4 mgkg(-1), respectively. These levels are low and are not considered to represent a threat to the S. attenuata population. No significant differences either in concentrations of HCB, tPCB and tDDT or in PCB profiles were observed between males and females. The ratio tDDT/tPCB was 2.69, indicating predominantly agrarian versus industrial activities in the area. The ratio ppDDE/tDDT was 0.83, a high figure that suggests both a local reduction of DDT inputs and a high rate of DDT degradation. Significant quantitative and qualitative differences were observed between two schools, suggesting intra-population heterogeneity in organochlorine exposure possibly due to demographic segregation.

Adipocytes↗
PubMed2003

[Evaluation of lercanidipine in the general practice setting].

OBJECTIVE: To determine the efficacy and tolerability of a long-acting dihydropyridine in the clinical settings of general practice. MATERIAL AND METHODS: 110 essential hypertensives were included (age 62.3 +/- 10.8 years, 51 men and 53 women, 38/ obese -IMC >30 kg/m2, ten diabetics). 104 patients ended the followup. Patients were treated with lercanidipine 10 mg once daily in the morning. Follow-up lasted 6 months. When blood pressure was not controlled (BP < 140/90 mmHg) in any visit, a second drug was added, excluding calcium channel blockers. Antiadrenergic drugs were recommended. If patients were not controlled ittwo consecutive visits they were excluded from follow-up. RESULTS: Significant reductions in both systolic (baseline 157.4 +/- 11.7 vs 131.1 +/- 6.8 mmHg, p < 0,001) and diastolic BP (baseline 94.7 +/- 5.8 vs 80.0 +/- 5.5 mmHg, p < 0,001) were attained at six months. Mean SBP decrease was 26.7 mmHg and mean DBP reduction was 15.6 mmHg. At the study end, 84.3/ of the patients achieved a BP < 140/90 mmHg. Thirty patients needed a second drug to become controlled (26 at the study end). The overall incidence of adverse effects was 4,4/ (n=6) and just three patients withdrew the treatment due to untoward effects. Plasmatic cholesterol lowered from 225.3 +/- 41.0 to 216.7 +/- 25.3 mg/dl (p = 0,03) and urate decreased from 5.6 +/- 1.6 to 5.1 +/- 1.4 mgldl, p = 0,03). CONCLUSIONS: Lercanidipine is a calcium channel blockers of high efficacy and low incidence of adverse effects in the clinical settings of general practice. It seems to have a positive metabolic effects on plasmatic levels of cholesterol and urate.

Aged↗
PubMed2002

Experimental link of photoionization of Sc2+ to photorecombination of Sc3+: an application of detailed balance in a unique atomic system.

The principle of microscopic time reversal of physical processes, detailed balance, is widely used and depended upon in the theoretical community as a connection between photorecombination (PR) and photoionization (PI). This paper reports on a novel use of detailed balance and the comparison of experimental results obtained by two very distinct techniques to determine both the metastable fraction of an ion beam and partial Sc3+ PR cross sections and partial Sc2+ PI cross sections for the ground state and for two metastable states. The Sc2+ to Sc3+ system presents a unique opportunity to obtain comprehensive state-selective information by combining results from PR and PI experiments.

Journal Article↗
PubMed2002

Geographical and temporal variation in levels of organochlorine contaminants in marine mammals.

The interpretation of the spatial and temporal patterns of variation in organochlorine concentrations in marine mammal populations is complex because of the lack of wide-scale, long-term surveys. Therefore the results from several surveys must be combined and this causes undesired heterogeneity due to differences in the sampling and analytical techniques used and in the biological characteristics of the individuals sampled. Moreover, information is not homogeneously distributed in either space or in time. Most research is concentrated in western Europe, northern America and certain areas of Asia, while it is extremely limited or non-existent in Africa and most regions of the southern hemisphere. Marine mammals from the temperate fringe of the northern hemisphere, particularly fish-eating species which inhabit the mid-latitudes of Europe and North America, show the greatest organochlorine loads; noteworthy are the extremely high levels found in the Mediterranean Sea and certain locations on the western coasts of the United States. Concentrations in the tropical and equatorial fringe of the northern hemisphere and throughout the southern hemisphere are low or extremely low. The polar regions of both hemispheres showed the lowest concentrations of DDTs and PCBs, although levels of HCHs, chlordanes and HCB were moderate to high in the cold waters of the North Pacific. During recent decades, concentrations have tended to decrease in the regions where pollution was initially high but they have increased in regions located far from the pollution source as a consequence of atmospheric transport and redistribution. It is expected that the Arctic and, to a lesser extent, the Antarctic, will become major sinks for organochlorines in the future; this process may already be significant for some compounds such as HCB and HCHs. Effort should be devoted to both assessment of organochlorine trends in the now highly polluted populations of the temperate fringe of the northern hemisphere and to the implementation of long-term monitoring of marine mammal populations inhabiting polar regions.

Animals↗
PubMed2002

Pre- and post-natal protein malnutrition alters the effect of rapid eye movements sleep-deprivation by the platform-technique upon the electrocorticogram of the circadian sleep-wake cycle and its frequency bands in the rat.

Selective deprivation of paradoxical (or rapid eye movements) sleep (REMS) in protein malnourished young male rats, results in circadian and homeostatic alterations. By means of electrocorticographic recordings, we have examined the sleep-wake cycle as a functional maturity index, and its circadian and homeostatic mechanisms in prenatal (PM) and chronically (CM) protein malnourished young male rats. The effects of rapid eye movements sleep-deprivation (REMS-D), by the platform technique in a "conflict experiment" (i.e. recovery from REMS-D begun during the circadian phase of activity), revealed that in PM animals, wake (WAK) was increased significantly during recovery days 1 and 2 (RD1, RD2); and slow wave sleep (SWS) was reduced significantly during these days. Prenatal protein-malnutrition altered the phase of WAK and REMS rhythms, and the amplitude of SWS rhythm was decreased. The REMS compensatory increase after REMS-D (REMS rebound) was confined to the first 4-h block of the activity phase in all experimental groups and 24 h later another REMS rebound was displayed in PM animals. The paradoxical sleep-rebound in CM animals was significantly higher than control and PM rats and it was only shown at the first 4-h block after REMS-D. Before and after REMS-D the circadian distribution of both sleep states, and the electrocortical frequency bands showed different circadian phases at the same day-time in control, PM and CM rats. The aforementioned indicates that protein malnutrition exerts important effects on the circadian and homeostatic mechanisms driving sleep. Therefore, the temporal structure of the malnourished rats may not allow proper synchronization of some sleep parameters, particularly REMS, to the environmental time cues.

Animals↗
PubMed2001

Photoionization of metastable O+ ions: experiment and theory.

High-resolution absolute experimental measurements and two independent theoretical calculations were performed for photoionization of O+ ions from the 2P(o) and 2D(o) metastable levels and from the 4S(o) ground state in the photon energy range 30-35.5 eV. This is believed to be the first comparison of experiment and theory to be reported for photoionization from metastable states of ions. While there is correspondence between the predicted and measured positions and relative strengths of the resonances, the cross-section magnitudes and fine structure are sensitive to the choice of basis states.

Journal Article↗
PubMed2001

Impact of epitope permutations in the antibody response of mice to a multi-epitope polypeptide of the V3 loop of human immunodeficiency virus type 1.

Our group have produced in Escherichia coli and evaluated the immunogenicity of different multi-epitope polypeptides (MEPs) bearing one copy of V3 loop sequential B cell epitopes from several isolates of human immunodeficiency virus type 1 (HIV-1) gp120. One of these MEPs called TAB9 comprises the 15 central amino acids of the V3 loop from isolates LR150, JY1, RF, MN, BRVA and IIIB in this order. Antibodies against all V3 regions were elicited after immunization of rabbits, macaques and humans with TAB9. In contrast, mice immunized with this protein only developed antibodies against epitopes JY1, LR150 and MN in that order (JY1>LR150>MN>>>RF, BRVA, IIIB) resembling an immunodominant gradient from the N-terminus to the C-terminal portion of this construction. To assess what role the location of the V3 epitopes in TAB9 could play, we constructed the protein TAB16, by altering the position of V3 epitopes in TAB9 primary structure and compared the pattern of antibodies elicited by both MEPs in H-2(d) Balb/c mice. The MEP TAB16 elicited antibody titers comparable to that of the sera from mice immunized with TAB9. There were no statistical differences in antibody titers between both groups (P>0.05). JY1, LR150 and MN V3 epitopes were again immunodominant in mice immunized with TAB16 fusion protein. The highest antibody titers detected in both groups among V3 epitopes corresponded to JY1, now located at the C-terminus of the permuted chimera. Antibodies against V3 epitopes RF, BRVA and IIIB were again not detected. Additionally, the MN V3 epitope showed to be significantly more immunogenic in its new orientation in TAB16, possibly as a result of a higher degree of accessibility in the surface of the protein. The results of the present investigation strongly suggest that the sequential order or the intramolecular position of V3 epitopes inside the primary structure of TAB9 and TAB16 MEPs does not interfere with the global immunogenicity or with the hierarchy of immunodominance of these regions.

Amino Acid Sequence↗
PubMed2001

Bioaccumulation of polychlorinated biphenyls (PCBs) and dichlorodiphenylethane (DDE) methyl sulfones in tissues of seal and dolphin morbillivirus epizootic victims.

Polychlorinated biphenyl (PCB) and dichlorodiphenylethane (DDE) methyl sulfone (MSF) metabolites possess high affinities for binding two homologous 16,000 Da homodimeric receptor proteins in the lung (Clara cell secretory protein, CCSP) and the uterus (uteroglobin, UG), leading to selective bioaccumulation of MSFs in these tissues. As marine mammals are highly exposed to organochlorines, concentrations of PCBs, PCB MSFs, DDT, and DDE MSF were analyzed in blubber, lung, and uterus samples from harbor seal (Phoca vitulina) and striped dolphin (Stenella coeruleoalba) morbillivirus epizootic victims to investigate uterine and lung MSF accumulation. Mean uterus concentrations of PCB MSFs and DDE MSF in harbor seals were 0.61 and 0.04 microg/g lipid weight and in striped dolphins 0.05 and 0.01 microg/g lipid weight. Mean lung concentrations of PCB MSFs and DDE MSF in harbor seals were 0.96 and 0.02 microg/g lipid weight and in striped dolphins 0.16 and 0.01 microg/g lipid weight. To ascertain whether uterine and lung bioaccumulation of MSFs is possible due to the presence of CCSP and UG in seals, CCSP and UG proteins in uterine flushings and in uterine and lung and epithelial tissue from Baltic gray and ringed seals were characterized using gel electrophoresis and Western blotting techniques. UG- and CCSP-like proteins with molecular weights of 16,000 Da were resolved in all samples. This is the first demonstration of this protein in any marine mammalian species. The toxicological implications of MSF binding with UG and CCSP in marine mammals are discussed.

Adipose Tissue↗
PubMed2001

Organochlorine compounds in common dolphins (Delphinus delphis) from the Atlantic and Mediterranean waters of Spain.

Blubber of free-ranging common dolphins (Delphinus delphis) from the northwestern coast of Spain (Atlantic), sampled in 1984 and 1996, and of common dolphins entangled in fishing nets in the southwestern Mediterranean, sampled during 1992 1994, was analysed for organochlorine pollutants. In the Atlantic, concentration of all pollutants was significantly higher in males than in females. The overall tPCB/tDDT ratio in this area was 3.35, which indicates a predominance of industrial inputs over those associated with agriculture. Individuals sampled in 1996 showed significantly lower DDT concentrations but a higher ppDDE/tDDT ratio than those sampled in 1984, which reflects the aging of the environmental load. In the same period, tPCB concentration remained constant and, as a consequence, the tPCB/tDDT ratio more than doubled. In the Mediterranean, the reduced sample size of adult individuals precluded proper statistical investigation of sex-related variation. The overall tPCB/tDDT ratio was 1.12, suggesting a higher contribution of pollutants of agricultural origin. Individuals had significantly higher levels of all DDT forms and a higher ppDDE/tDDT ratio than their counterparts from the Atlantic, but similar PCB concentrations. However, the relative frequency of the different congeners in relation to the total PCB load was different in the two areas. This indicates that the two populations do not mix, at least in the short- or medium-term. Organochlorine levels in both areas are at the mid to low end of the range of concentrations detected in other common dolphin populations and in that of other Delphinidae species from the same region. Although the impact of the organochlorine concentrations on the common dolphin populations surveyed cannot be assessed, it is considered unlikely that they have played a significant role in the decline that the species has suffered in recent decades in the western Mediterranean.

Adipose Tissue↗
PubMed2001

[Thrombopenia associated to localized scleroderma].

Two patients are reported with localized scleroderma who developed thrombocytopenia. One of these patients had a positive antinuclear antibody (ANA) and Anti-DNA antibodies tests. The occurrence of thrombocytopenia in localized scleroderma suggests an autoimmune mechanism, by the response to steroids and the presence of positive autoantibodies. This possible association emphasizes the need to look for hematologic disorders in patients with systemic, as well as localized scleroderma.

Adolescent↗
PubMed2000

Proliferating trichilemmal cyst with focal invasion: report of a case and a review of the literature.

Proliferating trichilemmal cyst (PTC) is a rare but morphologically distinctive tumor that usually occurs in the scalp of elderly women. Furthermore, only 30 well-documented examples of so-called malignant PTC have been reported. Alternatively, some authors have recently proposed that PTC is squamous cell carcinoma. We describe a case of PTC with focal invasion that was indistinguishable from squamous cell carcinoma in areas, and we review the literature. This debate should be considered in PTCs to provide adequate treatment (wide local excision) and follow-up (long term), particularly in large and long-standing lesions.

Aged↗
PubMed2000

Validation of the Minnesota Leisure Time Physical Activity Questionnaire In Spanish Women. Investigators of the MARATDON Group.

PURPOSE: Regular physical activity (PA) is associated with lower risk for several chronic diseases. It is important to validate PA measurement instruments in different populations. The objective was to validate the Minnesota leisure time PA questionnaire among Spanish women. METHODS: A cross-sectional study with quota sampling was designed. Two PA groups (active, expending less than 301 MET-min x d(-1) in PA, and very active, expending more than 300 MET-min x d(-1)) and two age groups (18-40 and 41-60 yr) were defined. The Minnesota questionnaire was administered to obtain total energy expenditure in leisure time PA (EEPAtotal) and classified according to the intensity of the different types of PA (EEPAheavy, EEPAmoderate, and EEPAlight). The 250 women recruited performed an exercise test to assess fitness. RESULTS: Spearman correlation coefficients among EEPAtotal, EEPAheavy, EEPAmoderate, EEPAlight, and fitness were 0.39, 0.51, 0.13, and 0.02, respectively. Multiple linear regression model adjusted by the different EEPAs and age accounted for 46% of fitness variability. Besides age, only EEPAmoderate and EEPAheavy were associated with fitness. CONCLUSION: The Spanish version of the Minnesota questionnaire is a valid instrument for measuring leisure time PA performed in the last year in Spanish women aged 18-60 yr. Moderate and heavy physical activity are adequately assessed whereas light physical activity practice assessment may be questionable.

Adolescent↗
PubMed2000

Cloning, sequencing, and role in serum susceptibility of porin II from mesophilic Aeromonas hydrophila.

We cloned and sequenced the structural gene for Aeromonas hydrophila porin II from strain AH-3 (serogroup O:34). The genetic position of this gene, like that of ompF in Escherichia coli, is adjacent to aspC and transcribed in the same direction. However, upstream of the porin II gene no similarities with E. coli were found. We obtained defined insertion mutants in porin II gene either in A. hydrophila (O:34) or A. veronii sobria (serogroup O:11) serum-resistant or -sensitive strains. Furthermore, we complemented these mutants with a plasmid harboring only the porin II gene, which allowed us to define the role of porin II as an important surface molecule involved in serum susceptibility and C1q binding in these strains.

Aeromonas hydrophila↗
PubMed2000

Clinical and bacteriologic efficacy of amoxycillin b.d. (45 mg/kg/day) versus amoxycillin t.d.s (40 mg/kg/day) in children with group A beta-hemolytic streptococcal tonsillopharyngitis.

This randomized, observer-blind, multicenter, parallel-group study compared the clinical and bacteriologic efficacy and safety of amoxycillin, 45 mg/kg/day b.d. and amoxycillin, 40 mg/kg/day t.d.s. after 7 days of treatment in 517 children with acute bacterial tonsillopharyngitis. At the end of treatment, a successful clinical response was recorded in more than 96% of patients in each of the treatment groups. A similar result was obtained at follow-up. Among those patients who were bacteriologically evaluable at the end of treatment, a successful bacteriologic response was achieved in more than 94% in each treatment group. Both treatments were well tolerated. Drug-related adverse events were recorded in just 12 patients (4.6%) in the b.d. group and six (2.4%) in the t.d.s. group. The study demonstrated that a twice-daily regimen of amoxycillin, 45 mg/kg/day, was as effective and as well tolerated as the standard three-times-daily regimen of amoxycillin, 40 mg/kg/day, in the treatment of acute bacterial tonsillopharyngitis in children.

Adenoids↗
PubMed2000

Transgrediens et progrediens palmoplantar keratoderma (Greither's disease) with particular histopathologic findings.

We describe a patient with transgrediens et progrediens palmoplantar keratoderma (Greither's disease). Ten of the 25 members of this patient's family in six consecutive generations were affected by the disorder. The pedigree was consistent with an autosomal dominant inheritance pattern, with variable penetrance. The proband's physical examination showed typical signs of Greither's disease. The most striking findings were seen in histopathologic study and consisted of round, focal areas of orthohyperkeratosis located on delled areas of the epidermis. These histopathologic features were present in both the lesions of the palms and dorsum of the hands. We review the clinical manifestations and histopathologic findings of this particular variant of palmoplantar keratoderma and the differential diagnosis.

Biopsy, Needle↗