Biomedical subjects

J Ballesteros

Publications and source records attributed to J Ballesteros.

At least 19 recordsLinked to original sources

PubMed2006

Doñana National Park survey using crayfish (Procambarus clarkii) as bioindicator: esterase inhibition and pollutant levels.

Utility of carboxylesterase and acetylcholinesterase inhibition as pesticide exposure biomarker was studied at Doñana National Park (SW Spain) in crayfish (Procambarus clarkii). Activities were measured in animals from reference sites or potentially exposed to pesticides, and their reactivation studied after dilution or 2-PAM treatment. Crayfish from affected sites had significantly less carboxylesterase and acetylcholinesterase activity than reference ones. No significant differences were found after dilution or 2-PAM treatment, showing that inhibition was irreversible. High pesticide levels were found in water and/or soil at rice growing sites, and lower levels at other affected places. High metal levels existed at rice growing sites and lower at other affected and at both reference sites. A combined effect on esterase inhibition of pesticides and metals is proposed. This field study suggest that the rice growing areas near Guadiamar stream are most polluted, followed by strawberry and citrics growing zones near Partido and Rocina streams. However, no correlation exist between the pesticide concentration at different sites and the extent of esterase inhibition, indicating that other factors could affect esterase response of animals from polluted sites.

Acetylcholinesterase↗

PubMed2006

Oncogenic human papillomavirus (HPV) type distribution and HPV type 16 E6 variants in two Spanish population groups with different levels of HPV infection risk.

The aim of this study is to determine oncogenic human papillomavirus (HPV) types and HPV type 16 (HPV16) variant distribution in two Spanish population groups, commercial sex workers and imprisoned women (CSW/IPW) and the general population. A multicenter cross-sectional study of 1,889 women from five clinical settings in two Spanish cities was conducted from May to November 2004. Oncogenic HPV infection was tested by an Hybrid Capture II (HC2) test, and positive samples were genotyped by direct sequencing using three different primer sets in L1 (MY09/11 and GP5+/GP6+) and E6/E7. HPV16 variants were identified by sequencing the E6, E2, and L1 regions. Four hundred twenty-five samples were positive for the HC2 test, 31.5% from CSW/IPW and 10.7% from the general population. HPV16 was the most frequent type. Distinct profiles of oncogenic HPV type prevalence were observed across the two populations. In order of decreasing frequency, HPV types 16, 31, 58, 66, 56, and 18 were most frequent in CSW/IPW women, and types 16, 31, 52, 68, 51, and 53 were most frequent in the general population. We analyzed HPV16 intratype variants, and a large majority (78.7%) belonged to the European lineage. AA variants were detected in 16.0% of cases. African variants belonging to classes Af1 (4.0%) and Af2 (1.3%) were detected. Different HPV types and HPV16 intratype variants are involved in oncogenic HPV infections in our population. These results suggest that HPV type distribution differs in CSW/IPW women and in the general population, although further analysis is necessary.

Adolescent↗

PubMed2005

Influence of age and geographical origin in the prevalence of high risk human papillomavirus in migrant female sex workers in Spain.

OBJECTIVES: To estimate the prevalence and risk factors of high risk human papillomavirus (HPV) infection in migrant female sex workers (FSW) according to age and geographical origin. METHODS: Cross sectional study of migrant FSW attending a sexually transmitted infection (STI) clinic in Madrid during 2002. Information on sociodemographic characteristics, reproductive and sexual health, smoking, time in commercial sex work, history of STIs, HIV, hepatitis B, hepatitis C, syphilis, and genitourinary infections was collected. High risk HPV Infection was determined through the Digene HPV Test, Hybrid Capture II. Data were analysed through multiple logistic regression. RESULTS: 734 women were studied. Overall HPV prevalence was 39%; 61% in eastern Europeans, 42% in Ecuadorians, 39% in Colombians, 29% in sub-Saharan Africans, and 24% in Caribbeans (p = 0.057). HPV prevalence showed a decreasing trend by age; 49% under 20 years, 35% in 21-25 years,14% over 36 years% (p<0.005). In multivariate analyses, area of origin (p = 0.07), hormonal contraception in women not using condoms (OR 19.45 95% CI: 2.45 to 154.27), smoking, age, and an interaction between these last two variables (p = 0.039) had statistically significant associations with HPV prevalence. STI prevalence was 11% and was not related to age or geographical origin. CONCLUSIONS: High risk HPV prevalence in migrant FSW is elevated and related to age, area of origin, and use of oral contraceptives in women not using condoms. These data support the role of acquired immunity in the epidemiology of HPV infection and identifies migrant FSW as a priority group for sexual health promotion.

Adolescent↗

PubMed2004

Reliability of the methods applied to assess age minority in living subjects around 18 years old. A survey on a Moroccan origin population.

We present a review of a population of 114 immigrant Moroccan males for which an age estimation was requested. The subjects' real chronological age was confirmed by the Moroccan Embassy in Spain. The confirmed age range was between 13 and 25, with an average age of 18.1 years and a standard deviation of 2.03. The following tests were performed to arrive at the forensic estimation of age: general physical examination, carpus X-ray (Greulich and Pyle method) and dental orthopantomography to determine the degree of maturity of the third inferior molars (Demirjian's method). Carpus X-ray (skeletal age) was the most useful method, followed by Demirjian's method (dental age), as prediction factors of a chronological age of over or under 18. The combination of skeletal and dental age variables represented a significant improvement in the prediction of the chronological age of the subjects in this population, reducing the number of ethically unacceptable test errors to a minimum.

Adolescent↗

PubMed2004

Evolution of biological effects of Aznalcóllar mining spill in the Algerian mouse (Mus spretus) using biochemical biomarkers.

The status of Guadiamar stream, polluted in 1998 by metals spilled from a pyrite tailings dam, was monitored from 1999 to 2001 to assess possible biological effects in terrestrial ecosystems of Doñana National Park (DNP) (Andalusia, SW Spain). The Algerian mouse (Mus spretus) was used as bioindicator at different Guadiamar and Doñana sites. Eleven biochemical parameters, including the activities of antioxidative and biotransforming enzymes and oxidative damages to biomolecules, were assayed in liver as biomarkers responsive to metals and organic pollutants. In 2001, metals were also determined in kidney and their possible correlation with biomarker responses was studied. Contents of Pb, Cd and As significantly correlated with several antioxidative enzymes. Biomarkers responsive to oxidative stress indicate the presence of transition metals in the high and medium Guadiamar course, and their response diminished with the distance to the collapsed dam. The high ethoxyresorufin-O-deethylase (EROD) activity of mice from the medium and low Guadiamar course point to organic pollutants, such as the pesticides used in intensive crops grown in areas nearby Doñana. The increasing responses of several biomarkers at reference sites may suggest a progressive pollution of key Doñana ecosystems.

Animals↗

PubMed2004

Differences among auxin treatments on haploid production in durum wheat x maize crosses.

Three doubled haploid lines of durum wheat [Triticum turgidum ssp. durum (Desf.) Husn.] were crossed with maize (Zea mays L.), and five hormone treatments were applied to test their effect on the production of caryopses, embryos and haploid plants. The auxin treatments consisted of 100 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D), 5 mg/l or 50 mg/l dicamba and two combination mixtures of 95/5 mg/l and 50/50 mg/l 2,4-D plus dicamba, respectively. Hormones were added to the culture medium of the detached tillers. Differences were not observed among the four hormone treatments that contained dicamba, nevertheless, these treatments significantly increased the production of caryopses, embryos and haploid plants. On average, 8.9 caryopses, 2.6 embryos and 1.3 haploid plants per spike were obtained following the treatment with 100 mg/l 2,4-D, and 15.0 caryopses, 6.0 embryos and 3.0 haploid plants per spike were obtained following the various treatments with dicamba. We propose the application of dicamba alone, or dicamba plus 2,4-D, as a means for improving the yield of haploid plants of durum wheat through crosses with maize.

2,4-Dichlorophenoxyacetic Acid↗

PubMed2003

Principal components of mania.

OBJECTIVE: An alternative to the categorical classification of psychiatric diseases is the dimensional study of the signs and symptoms of psychiatric syndromes. To date, there have been few reports about the dimensions of mania, and the existence of a depressive dimension in mania remains controversial. The aim of this study was to investigate the dimensions of manic disorder by using classical scales to study the signs and symptoms of affective disorders. METHODS: One-hundred and three consecutively admitted inpatients who met DSM IV criteria for bipolar disorder, manic or mixed were rated with the Young Mania Rating Scale (YMRS) and the Hamilton Depression Rating Scale (HDRS-21). A principal components factor analysis of the HDRS-21 and the YMRS was carried out. RESULTS: Factor analysis showed five independent and clinically interpretable factors corresponding to depression, dysphoria, hedonism, psychosis and activation. The distribution of factor scores on the depressive factor was bimodal, whereas it was unimodal on the dysphoric, hedonism and activation factors. Finally, the psychosis factor was not normally distributed. LIMITATIONS: Patients of the sample were all medicated inpatients. CONCLUSIONS: Mania seems to be composed of three core dimensions, i.e. hedonism, dysphoria and activation, and is frequently accompanied by a psychotic and a depressive factor. The existence of a depressive factor suggests that it is essential to evaluate depression during mania, and the distribution of the depressive factor supports the existence of two different states in mania.

Adolescent↗

PubMed2002

Introgression of 1Dx5+1Dy10 into tritordeum.

The uses of hexaploid tritordeum as a crop for human consumption require improvement of its bread-making quality. For this purpose chromosome 1D of bread wheat with the Glu-D1 allele encoding for high-molecular-weight glutenin subunits Dx5+Dy10 was introgressed into tritordeum. Different primary tritordeums were crossed with wheats carrying subunits Dx5+Dy10. The hybrids were backcrossed to tritordeum and seeds for the next backcross (or selfing) were selected for the presence of chromosome 1D using SDS-PAGE. Forty two chromosome plants carrying subunits Dx5+Dy10 were obtained after two backcrosses and selfing. Chromosome characterization of these plants using fluorescence in situ hybridisation (FISH) proved that either chromosome substitution 1H(ch)/1D or 1A/1D had been obtained. A homozygous plant with a translocation of the entire 1DL arm to 1H(ch)S was also obtained. The complete chromosome substitution lines have better agronomic characteristics than the lines with translocations.

Alleles↗

PubMed2002

[HIV prevalence among homosexual and bisexual men in Spain, 1992-2000].

BACKGROUND: Our purpose was to describe the time trend in HIV seroprevalence among homo/ bisexual men. SUBJECTS AND METHOD: We analyzed 9,383 homo/ bisexual men who had a first voluntary test for HIV in 10 Spanish clinics from 1992 to 2000. RESULTS: HIV prevalence decreased from 20.3% in 1992 to 8.4% in 2000. In the multivariate analysis this decline appeared independently associated with the testing year and the birth cohort. CONCLUSIONS: New generations of voluntarily tested homo/bisexual men are less infected by HIV, but it is yet necessary to intensify the prevention programs.

Adolescent↗

PubMed2002

Quality of life in patients with schizophrenia in five European countries: the EPSILON study.

OBJECTIVE: To compare subjective quality of life (QOL) and objective QOL indicators in patients with schizophrenia from five European sites: Amsterdam, Copenhagen, London, Santander and Verona. METHOD: A representative sample of 404 patients with schizophrenia, in contact with mental health services, was randomly selected and evaluated with the Lancashire Quality of Life Profile (EU). RESULTS: The level of satisfaction in certain domains, religion, family and social relations appears to be associated with local style of living and culture while work, finances, and safety were more independent from local variations. In addition to the severity of symptoms, frequency of contacts with family, friendship and age appear as predictors of QOL, all of them influenced by the characteristics of the surroundings. CONCLUSION: The centres participating in the study presented differences in subjective measures of QOL, objective indicators and also in service provision and styles of living.

Adult↗

PubMed2001

Differential [(3)H]idazoxan and [(3)H]2-(2-benzofuranyl)-2-imidazoline (2-BFI) binding to imidazoline I(2) receptors in human postmortem frontal cortex.

[(3)H]2-(2-benzofuranyl)-2-imidazoline (2-BFI) and [(3)H]idazoxan are the most used tools to characterise imidazoline I(2) receptors. We evaluated the binding of both radioligands to human postmortem frontal cortex membranes. Saturation binding analyses revealed that [(3)H]idazoxan (in the presence of 2 microM efaroxan to avoid radioligand binding to alpha(2)-adrenoceptors and imidazoline I(1) receptors) and [(3)H]2-BFI bound with high affinity to an apparent single population of sites. However, in competition studies whereas [(3)H]idazoxan (10 nM) binding was displaced monophasically by idazoxan and 2-BFI, both drugs displayed biphasic curves for [(3)H]2-BFI (1 nM). The proportion of the low-affinity binding site increased from 17% to 25% when 10 nM [(3)H]2-BFI was displaced by idazoxan. Amiloride inhibited [(3)H]2-BFI (10 nM) binding with low affinity and in a monophasic way. These data indicate that [(3)H]2-BFI recognises in human postmortem brain membranes a second binding site different from the imidazoline I(2) receptors labelled by [(3)H]idazoxan.

Adrenergic alpha-Antagonists↗

PubMed2001

Time trend in incidence of HIV seroconversion among homosexual men repeatedly tested in Madrid, 1988--2000.

An open cohort of 2670 homosexual men repeatedly tested for HIV at a Madrid clinic has registered 8050 person-years (PY) of follow-up and 157 seroconversions from 1988 to 2000. After declining from 1988 (4.71 per 100 PY), the incidence rate began a significant upward trend, reaching a figure of 2.16 per 100 PY in 2000. These findings ought to alert surveillance systems and prevention programmes.

AIDS Serodiagnosis↗

PubMed2001

Herpes simplex virus type 2 seroepidemiology in Spain: prevalence and seroconversion rate among sexually transmitted disease clinic attendees.

BACKGROUND: Only limited data on the seroprevalence of herpes simplex virus type 2 (HSV-2) are available from European countries. Until recently, serologic tests for HSV-2 serotyping have been hampered by cross-reactivity to type-common antigens. The present study aims at providing data on the prevalence of HSV-2 infection in a group of STD clinic attendees using a reliable type-specific immunoassay. GOAL: To evaluate the seroprevalence of HSV-2 and the accumulated incidence of clinical genital herpes infection in a sample of Spanish sexually transmitted disease (STD) clinic attendees. STUDY DESIGN: The study consisted of two parts. First, a cross-sectional study of HSV-2 seroprevalence was conducted in patients with STDs. Second, a prospective cohort study was undertaken to evaluate the accumulated incidence of infection by HSV-2 and of clinical episodes of genital herpes in HSV-2-negative patients included in the first study during a follow-up period of 6 to 18 months. RESULTS: Of the 374 patients (129 men, 245 women) studied, 25% were seropositive for HSV-2 (12% of men, 30% of women). Antibodies to HSV-2 were related to female gender (odds ratio, 2.7; P < 0.001) and to the number of sexual partners (odds ratio, 4.1; P < 0.001). Fifty-two percent of patients (145 of 281 patients) who were initially seronegative returned to the clinic for a second serologic testing, of whom 1% (2 of 145 patients) had seroconverted. None of the patients developed genital herpes during the follow-up period. CONCLUSION: The relatively high seroprevalence (25%) and the low rate (4%) of HSV-2 previously reported in the general population in Spain suggest that the virus circulation may be restricted to certain risk groups. Therefore, future healthcare measures may target specific groups, such as patients with STDs.

Antibodies, Viral↗

PubMed2001

Prospects for exploitation of disease resistance from Hordeum chilense in cultivated cereals.

Hordeum chilense is a South American wild barley with high potential for cereal breeding given its high crossability with other members of the Triticeae. In the present paper we consider the resistance of H. chilense to several fungal diseases and the prospects for its transference to cultivated cereals. All H. chilense accessions studied are resistant to the barley, wheat and rye brown rusts, the powdery mildews of wheat, barley, rye and oat, to Septoria leaf blotch, common bunt and to loose smuts, which suggests that H. chilense is a non-host of these diseases. There are also lines resistant to wheat and barley yellow rust, stem rust and to Agropyron leaf rust, as well as lines giving moderate levels of resistance to Septoria glume blotch, tan spot and Fusarium head blight. Some H. chilense lines display pre-appressorial avoidance to brown rust. Lines differ in the degree of haustorium formation by rust and mildew fungi they permit, and in the degree to which a hypersensitive response occurs after haustoria are formed. Unfortunately, resistance of H. chilense to rust fungi is not expressed in tritordeum hybrids, nor in chromosome addition lines in wheat. In tritordeum, H. chilense contributes quantitative resistance to wheat powdery mildew, tan spot and loose smut. The resistance to mildew, expressed as a reduced disease severity, is not associated with macroscopically visible necrosis. Hexaploid tritordeums are immune to Septoria leaf blotch and to common bunt although resistance to both is slightly diluted in octoploid tritordeums. Studies with addition lines in wheat indicate that the resistance of H. chilense to powdery mildew, Septoria leaf blotch and common bunt is of broad genetic basis, conferred by genes present on various chromosomes.

Fusarium↗

PubMed2001

Identification of intergenomic translocations involving wheat, Hordeum vulgare and Hordeum chilense chromosomes by FISH.

Intergenomic translocations between wheat, Hordeum chilense and Hordeum vulgare have been obtained in tritordeum background. Advanced lines from the crosses between three disomic chromosome addition lines for chromosome 2Hv, 3Hv, and 4Hv of barley (Hordeum vulgare) in Triticum aestivum cv. Chinese Spring (CS) and hexaploid tritordeum (2n = 6x = 42, AABBHchHch) were analyzed. Multicolor FISH using both genomic DNA from H. chilense and H. vulgare were used to establish the presence and numbers of H. vulgare introgressions into tritordeum. Interspecific H. vulgare/H. chilense and intergeneric wheat/H. vulgare and wheat/H. chilense translocations were identified. Frequencies of plants containing different kinds of intergenomic translocations between chromosome arms are presented. These lines can be useful for introgressing into tritordeum characters of interest from H. vulgare.

Chromosomes↗

PubMed2001

G protein-coupled receptor drug discovery: implications from the crystal structure of rhodopsin.

G protein-coupled receptors (GPCRs) are a functionally diverse group of membrane proteins that play a critical role in signal transduction. Because of the lack of a high-resolution structure, the heptahelical transmembrane bundle within the N-terminal extracellular and C-terminal intracellular region of these receptors has initially been modeled based on the high-resolution structure of bacterial retinal-binding protein, bacteriorhodopsin. However, the low-resolution structure of rhodopsin, a prototypical GPCR, revealed that there is a minor relationship between GPCRs and bacteriorhodopsins. The high-resolution crystal structure of the rhodopsin ground state and further refinements of the model provide the first structural information about the entire organization of the polypeptide chain and post-translational moieties. These studies provide a structural template for Family 1 GPCRs that has the potential to significantly improve structure-based approaches to GPCR drug discovery.

Amino Acid Sequence↗

PubMed2000

Structural probing of a microdomain in the dopamine transporter by engineering of artificial Zn2+ binding sites.

Previously, we have identified three Zn(2+) binding residues in an endogenous Zn(2+) binding site in the human dopamine transporter (hDAT): (193)His in extracellular loop 2 (ECL 2), (375)His at the external end of transmembrane segment (TM) 7, and (396)Glu at the external end of TM 8. Here we have generated a series of artificial Zn(2+) binding sites in a domain situated around the external ends of TMs 7 and 8 by taking advantage of the well-defined structural constraints for binding of the zinc(II) ion. Initially, we found that the Zn(2+)-coordinating (193)His in ECL 2 could be substituted with a histidine inserted at the i - 4 position relative to (375)His in TM 7. In this mutant (H193K/M371H), Zn(2+) potently inhibited [(3)H]dopamine uptake with an IC(50) value of 7 microM as compared to a value of 300 microM for the control (H193K). These data are consistent with the presence of an alpha-helical configuration of TM 7. This inference was further corroborated by the observation that no increase in the apparent Zn(2+) affinity was observed following introduction of histidines at the i - 2, i - 3, and i - 5 positions. In contrast, introduction of histidines at positions i + 2, i + 3, and i + 4 all resulted in potent inhibition of [(3)H]dopamine uptake by Zn(2+) (IC(50) = 3-32 microM). These observations are inconsistent with continuation of the helix beyond position 375 and indicate an approximate boundary between the end of the helix and the succeeding loop. In summary, the data presented here provide new insight into the structure of a functionally important domain in the hDAT and illustrate how engineering of Zn(2+) binding sites can be a useful approach for probing both secondary and tertiary structure relationships in membrane proteins of unknown structure.

Amino Acid Sequence↗

PubMed2000

I2-Imidazoline receptors and monoamine oxidase B enzyme sites in human brain: covariation with age.

An association between monoamino oxidase B enzyme (MAO-B) sites and I(2)-imidazoline receptors (I(2)-IR) has been established in human brain on the basis of correlational studies of radiolabelled binding sites. Because both MAO-B and I(2)-IR densities increase with aging, the age at death could be partially involved in the observed correlations. The evaluation of two independent but similar datasets demonstrated that the linear correlation between MAO-B and I(2)-IR densities dropped from 0.70 (P=0.02) and 0.41 (P=0.14) in the crude analyses to the negligible values of 0.07 (P=0.84) and 0.09 (P=0.75) when the age at death was controlled for in the statistical analyses. The results lead to conclude, contrary to former interpretations, that there is not any statistical association linking both MAO-B catalytic unit sites and I(2)-IR densities in the human brain.

Adolescent↗