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A Domínguez

Publications and source records attributed to A Domínguez.

At least 73 records · Page 4Linked to original sources
PubMed2001

The seroepidemiology of B. pertussis infection in Catalonia, Spain.

A survey of the seroprevalence of pertussis antibodies in a representative sample of the population from Catalonia was carried out. Ninety-seven municipalities and 30 schools were randomly selected to recruit the 2126 subjects who participated in the study. A serum sample was obtained from all individuals participating in the study in order to determine levels of pertussis toxin (PT) and filamentous hemagglutinin (FHA) antibodies by ELISA test. Sociodemographic data were collected for all subjects. The prevalence of PT antibodies was 75% and that of FHA antibodies 89%. Significant increments were observed with age, both in the prevalence of PT (P < 0.0001) and of FHA (P = 0.018). Of the sociodemographic variables studied, only urban habitat was significantly associated to PT antibodies. The agreement observed among the two types of antibodies studied was weak (K = 0.264). Routine revaccination with the acellular vaccine in children over 7 years of age, in adolescents and adults seems a reasonable strategy to prevent the appearance of cases of pertussis in the community.

Adhesins, Bacterial↗
PubMed2001

Prevalence of Neisseria meningitidis carriers in the school population of Catalonia, Spain.

The aim of this study was to determine the prevalence of healthy Neisseria meningitidis pharyngeal carriers in a representative sample of the Catalonian school population, as well as its associated factors. The sample was divided into age groups: < or = 5, 6-7 and 13-14 years old. Parents were given a questionnaire to collect information on sociodemographic and epidemiological variables. Oropharyngeal swabs were collected with a cotton-tipped swab in an Amies transport medium and cultured on Thayer Martin plates at 35 degrees C in 5% CO2. The isolates were serogrouped and sero/subtyped. Of the 1406 children studied, 75 (5.34%) meningococcal carriers were detected: 63 B (4.5%), 9 non groupable (0.7%), 2 29E (0.1%) and 1X (0.07%). No serogroup C meningococci were found in this study, probably due to the high A+C vaccination coverage of up to 68.9% in children 6-7 years old. Bivariate analysis identified six statistically significant risk factors for meningococcal carriage: increasing age, recent upper respiratory tract infection, previous antibiotic treatment, number of students in the class, size of the classroom and social class. Multivariate analysis found that only age and previous antibiotic treatment remained statistically significant when the other factors were controlled.

Adolescent↗
PubMed2001

Estimated varicella incidence on the basis of a seroprevalence survey.

Varicella is a disease caused by varicella-zoster virus. It is transmitted via the respiratory route, is highly communicable and mainly affects young children. An effective vaccine is now available, whose routine use is advised by health authorities in the USA and which can prevent severe disease, although breakthrough infections do occur. In deciding whether or not to include a vaccine in the routine vaccination schedule, knowledge of the morbidity of the disease in question is fundamental. Although reporting of varicella is compulsory in Catalonia, doctors only have to report the weekly number of cases diagnosed, and not their age distribution. Given that recent data on the prevalence of the infection in Catalonia according to age groups is available, it was considered that, using these data, an estimation of age-related incidence could be made. The objective of the present study was to estimate the incidence of varicella in Catalonia on the basis of the available seroprevalence data. A curve was fitted to the observed prevalence and point prevalence estimates for all ages were obtained. The incidence was derived by smoothed prevalence for each of these age groups. Estimated variance of the estimated incidence was obtained by the delta method. Predicted prevalence in the 0-4 years age group was calculated by the smoothed prevalence. The model that best fitted the sample prevalence was the exponential function. The estimated number of varicella cases in this study was 46,419 (95% CI 40,507-52,270). As the population in Catalonia in 1996 was 6,090,040, the previous results give an incidence rate of 762.2 per 100,000 persons/year with their 95% CI (666.1-858.3). The method described may be applied to the study of incidence rates in relation to the prevalence of diseases if we accept that the infection produces permanent immunity; the risk of mortality is the same for infected and non-infected subjects and that the disease incidence and population remain constant in time.

Adolescent↗
PubMed2001

Utilisation of lignocellulosic wastes for lignin peroxidase production by semi-solid-state cultures of Phanerochaete chrysosporium.

In the present work, the production of ligninolytic enzymes by semi-solid-state cultures of Phanerochaete chrysosporium BKM-F-1767 (ATCC 24725), employing different lignocellulosic wastes as support, was investigated. The waste materials employed were grape seeds, wheat straw and wood shavings. Maximum lignin peroxidase activities of 1,620 +/- 123 U/l,364 +/- 35 U/l and 571 +/- 42 U/l were attained, respectively. Nevertheless, low manganese-dependent peroxidase activities were found, being insignificant in the grape seed cultures. Moreover, the in vivo decolourisation of a model dye compound, the polymeric dye Poly R-478 (polyvinylamine sulfonate anthrapyridone), by the above-mentioned cultures was monitored to assess the degrading capability of the extracellular liquid secreted by such cultures. The percentage of biological decolourisation attained by grape seed and wood shaving cultures was around 74% and 63%, respectively, whereas it was rather low (40%) in the wheat straw ones.

Carbohydrates↗
PubMed2001

Carriers of Neisseria meningitidis in household contacts of meningococcal disease cases in Catalonia (Spain).

A population-based study was carried out in Catalonia (Spain) from May 1998 to April 1999 to determine the prevalence of Neisseria meningitidis strains in meningococcal disease (MD) cases and their contacts, as well as the prevalence of meningococci in close contacts of patients with MD, and risk factors for its carriage. A total of 364 close contacts of 87 patients with MD were studied. Throat samples were collected by hospital staff before rifampicin chemoprophylaxis was begun. For each contact, a questionnaire was completed for sociodemographic and epidemiological data. A total of 61 contacts (an overall prevalence of 16.8%) were carriers of meningococcal strains (40 B, 10 C, 1 Z and 10 non-groupable isolates). This prevalence is two to three times higher than in the general population (5-10%). In 33/61 microbiologically confirmed cases (54%) and in 9/26 probable cases (35%), contacts carrying N. meningitidis were found. In 22/33 confirmed cases with carrier contacts, it was possible to study the phenotype of the carrier and patient strains (sero-group, serotype and serosubtype). In 14 cases (64%), both strains were identical, in four cases, only a minor change was observed, in three cases, some strain (from the case or from his contact) was non-serotypable and non-serosubtypable, and in one case, both isolates were completely different. Bivariate analysis identified five statistically significant risk factors for meningococcal carriage: age (5-9 years old), meningococcal A+C vaccination, severe household overcrowding, social class and heavy active smoking (>20 cigarettes a day). Multivariate analysis revealed that of these five variables, only heavy active smoking remained statistically significant when the other factors were controlled.

Adolescent↗
PubMed2001

Dramatic decline of serogroup C meningococcal disease incidence in Catalonia (Spain) 24 months after a mass vaccination programme of children and young people.

STUDY OBJECTIVES: The objective of this study was to evaluate the effectiveness of a mass vaccination programme carried out in Catalonia (Spain) in the last quarter of 1997 in response to an upsurge of serogroup C meningococcal disease (SCMD). DESIGN: Vaccination coverage in the 18 month to 19 years age group was investigated by means of a specific vaccination register. Vaccination effectiveness was calculated using the prospective cohort method. Cases of SCMD were identified on the basis of compulsory reporting and microbiological notification by hospital laboratories. Vaccination histories were investigated in all cases. Unadjusted and age adjusted vaccination effectiveness referred to the time of vaccination and the corresponding 95% confidence intervals (CI) were estimated at 6, 12, 18 and 24 months of follow up. SETTING: All population aged 18 months to 19 years of Catalonia. MAIN RESULTS: A total of seven cases of SCMD were detected at six months of follow up (one in the vaccinated cohort), 12 cases at 12 months (one in the vaccinated cohort), 19 cases at 18 months (two in the vaccinated cohort) and 24 at 24 months (two in the vaccinated cohort). The age adjusted effectiveness was 84% (95%CI 30, 97) at six months, 92% (95%CI 63, 98) at 12 months, 92% (95% CI 71, 98) at 18 months and 94% (95%CI 78, 98) at 24 months. In the target population, cases have been reduced by more than two thirds (68%) two years after the vaccination programme. In the total population the reduction was 43%. CONCLUSION: Vaccination effectiveness has been high in Catalonia, with a dramatic reduction in disease incidence in the vaccinated cohort accompanied by a relevant reduction in the overall population. Given that vaccination coverage was only 54.6%, it may be supposed that this vaccination effectiveness is attributable, in part, to the herd immunity conferred by the vaccine.

Adolescent↗
PubMed2001

C282Y and H63D mutations of the haemochromatosis gene in patients with iron overload.

OBJECTIVE: To determine the relevance of C282Y and H63D mutations of HEF gene in patients with iron overload. PATIENTS AND METHODS: Patients with iron overload referred to our Liver Unit were included in the study. The association of mutations to different diagnosis and their impact on the severity of the hepatopathy were explored. Sensitivity, specificity and positive and negative predictive values of mutations for the diagnosis of haemochromatosis were determined. RESULTS: The study included 78 patients with iron overload. The control group included 21 patients of similar age and sex ratio without iron overload nor hepatopathy. Twenty three patients had haemochromatosis, 22 alcoholic liver disease and 33 other diseases unrelated to iron metabolism. Seventy three per cent of patients with haemochromatosis were homozygous for the C282Y mutation. All the C282Y homozygous subjects had also haemochromatosis. Fifty three per cent of patients with alcoholic hepatopathy had some kind of mutation. This has been also observed in 70% of patients with iron-unrelated diseases. Such percentage was significantly greater than in the control group (24% with H63D mutation). C282Y homozygosity in patients with iron overload had a sensitivity of 73.9%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 89.6%. CONCLUSIONS: In our population, as in all the Western countries, haemochromatosis is mainly associated to homozygous C282Y mutation. The high frequency of mutations in patients with iron overload and without haemochromatosis suggests the involvement of such mutations in iron overload.

Female↗
PubMed2001

Confirmed interruption of indigenous measles transmission in Catalonia.

From November 1998 to December 2000, 84 suspected measles cases were reported in Catalonia (6 090 040 inhabitants). Of the 73 laboratory tested cases (87%), 20 showed IgM antibodies specific to measles and 3 were epidemiologically linked to a confirmed case. Among these 23 confirmed cases, 13 were indigenous, the last two cases reported dating back from June 1999 and July 2000. These results confirm the success of the measles elimination programme implemented in 1998 in Catalonia.

Antibodies, Viral↗
PubMed2000

Hepatitis A and B in children and adolescents--what can we learn from Puglia (Italy) and Catalonia (Spain)?

Viral hepatitis remains a major contributor to the global disease burden. Mass immunisation strategies against hepatitis B have been adopted by more than 90 developing and industrialised countries. Countries with low hepatitis A endemicity are experiencing cyclical outbreaks and an epidemiological shift, with larger numbers of individuals at risk of infection at an older age, resulting in increased morbidity. The high cost of outbreaks in these countries has made immunisation strategies cost-effective. The development of a vaccine against hepatitis A and a combined vaccine against hepatitis A and hepatitis B offers potentially exciting opportunities for a preventative approach in areas of both low and high endemicity. Existing mass immunisation programmes against hepatitis B will facilitate the adoption of joint strategies illustrated by the examples of Puglia (Italy) and Catalonia (Spain).

Adolescent↗
PubMed2000

Seroepidemiology of varicella-zoster virus infection in Catalonia (Spain). Rationale for universal vaccination programmes.

With the aim of designing a strategy for vaccination against varicella-zoster virus (VZV), the results of a seroepidemiological survey on VZV infection carried out in a sample of the population of Catalonia are presented. Representative samples from schoolchildren (30 schools) and adults (97 municipal areas) were obtained by random cluster sampling. In the study, 883 children and 1253 adults were included. Age, gender, place of birth, place of residence, educational level and occupation were investigated in the study subjects. An ELISA test was used to measure varicella antibodies. The prevalence of varicella antibodies increased with age, being 85% in the 5-9 years age group, 92% in the 10-14 years age group, 94% in the 15-34 years age group and almost 100% in people over 35. No association was found between sociodemographic variables studied and prevalence levels of antibodies. These results suggest that the best vaccination strategy in Catalonia would be to add a temporary vaccination programme of pre-adolescents at 12 years to routine vaccination at 15 months.

Adolescent↗
PubMed2000

[Norwalk virus-like food poisoning after eating oysters].

BACKGROUND: The aim of this study was to conduct a clinical-epidemiological and microbiological investigation into an outbreak of food-borne disease due to the consumption of oysters. PATIENTS AND METHODS: A historic cohort study was conducted into the consumption of 15 food items and clinical symptoms. The influence of each foodstuff was assessed by Mantel-Haenzel stratified relative risk (RRM-H) at 95% confidence intervals, and was confirmed by dose-response analysis with a chi 2 test tendency. We investigated sample stools from 5 patients and 2 food-handlers. RESULTS: The overall attack rate was 38.0% (19/50). The median period of incubation was 39.0 h (maxim 62 and minimum 3 h). The symptoms were: fever 17.6% (3/17), diarrhoea 57.9% (11/19), vomits 84.2% (16/19), nausea 89.5% (17/19) and abdominal pain 89.5% (17/19). In stratified analysis, the Mantel-Haenzel method revealed a statistically risk for oysters (RRM-H = 3.3; IC 95%: 1.1-8.7), while the RRM-H value for sea snails was not significant (RRM-H = 2.8; IC 95%: 0.9-41.1). For oyster consumption, the dose-response test was statistically significant (p = 0.005). Examination by electron microscopy revealed small round structured viruses compatible with Norwalk-like virus. The oyster contamination was reported to the public health authority. CONCLUSIONS: This research highlights the usefulness of dose-response analysis in presenting epidemiological evidence, reveals the potential role of oyster consumption in food-borne disease such us Norwalk-like virus and show the need for monitoring production centres and oyster beds in order to prevent further cases of contamination.

Adult↗
PubMed2000

Changes in the seroepidemiology of hepatitis B infection in Catalonia 1989-1996.

The objective of this study was to investigate the prevalence of hepatitis B markers in a representative sample of 2142 subjects in Catalonia, Spain, and to compare it with previous studies. Multiple logistical regression analysis was carried out to determine variables associated with the markers studied. The prevalence of anti-HBc and HBsAg was 9.1% and 1.2%, respectively. Male gender, urban habitat, birth place outside Catalonia and lower social class were associated with the presence of anti-HBc. Carrier status was only associated with male gender. Between 1989 and 1996 there was a decrease of 46% in the prevalence of serum HBV markers mainly in the 25-44 (P<0.0001) and 35-64 year (P=0.0002) age groups, in those born in Catalonia (P=0.003) and in those in the higher social classes (P<0.0001). These decreases can be explained by the improved socioeconomic conditions and, partially, by the routine pre-adolescent and risk group programmes of immunization.

Adolescent↗
PubMed2000

Cell cycle regulated expression and phosphorylation of hpttg proto-oncogene product.

We recently isolated a cDNA for hpttg, the human homolog of rat pituitary tumor transforming gene. Now we have analysed the expression of hpttg as a function of cell proliferation. hPTTG protein level is up-regulated in rapidly proliferating cells, is down-regulated in response to serum starvation or cell confluence, and is regulated in a cell cycle-dependent manner, peaking in mitosis. In addition, we show that hPTTG is phosphorylated during mitosis. Immunodepletion and in vitro phosphorylation experiments, together with the use of a specific inhibitor, indicate that Cdc2 is the kinase that phosphorylates hPTTG. These results suggest that hpttg is induced by, and may have a role in, regulatory pathways involved in the control of cell proliferation.

Amino Acid Sequence↗
PubMed2000

Optimization of culture medium for the continuous cultivation of the microalga Haematococcus pluvialis.

The freshwater microalga Haematococcus pluvialis is one of the best microbial sources of the carotenoid astaxanthin, but this microalga shows low growth rates and low final cell densities when cultured with traditional media. A single-variable optimization strategy was applied to 18 components of the culture media in order to maximize the productivity of vegetative cells of H. pluvialis in semicontinuous culture. The steady-state cell density obtained with the optimized culture medium at a daily volume exchange of 20% was 3.77 x 10(5) cells ml(-1), three times higher than the cell density obtained with Bold basal medium and with the initial formulation. The formulation of the optimal Haematococcus medium (OHM) is (in g l(-1)) KNO3 0.41, Na2HPO4 0.03, MgSO4 x 7H2O 0.246, CaCl2 x 2H2O 0.11, (in mg l(-1)) Fe(III)citrate x H2O 2.62, CoCl2 x 6H2O 0.011, CuSO4 x 5H2O 0.012, Cr2O3 0.075, MnCl2 x 4H2O 0.98, Na2MoO4 x 2H2O 0.12, SeO2 0.005 and (in microg l(-1)]) biotin 25, thiamine 17.5 and B12 15. Vanadium, iodine, boron and zinc were demonstrated to be non-essential for the growth of H. pluvialis. Higher steady-state cell densities were obtained by a three-fold increase of all nutrient concentrations but a high nitrate concentration remained in the culture medium under such conditions. The high cell productivities obtained with the new optimized medium can serve as a basis for the development of a two-stage technology for the production of astaxanthin from H. pluvialis.

Chlorophyta↗
PubMed2000

Prevalence of Haemophilus influenzae carriers in the Catalan preschool population. Working Group on Invasive Disease Caused by Haemophilus influenzae.

This study was designed to determine the prevalence of healthy Haemophilus influenzae carriers in a random sample of the preschool population in Catalonia. Oropharyngeal swabs were collected and cultured on chocolate agar supplemented with 260 microg/ml of bacitracin. Four hundred two of the 734 (54.8%) children studied were detected as Haemophilus influenzae carriers: 7 (0.9%) carried serotype b, 14 (1.9%) serotype e, 6 (0.8%) serotype f, and 375 (51%) carried nontypable strains. The results show that, although the prevalence of Haemophilus influenzae carriers is similar to figures reported from other countries, the prevalence of Haemophillus influenzae serotype b carriers is lower and corresponds with the low incidence of invasive disease observed in the Catalan community.

Carrier State↗
PubMed2000

Estimation of microsatellite mutation rates in Drosophila melanogaster.

Microsatellite mutations were studied in a set of 175 mutation accumulation lines, all of them independently derived from a completely homozygous population of Drosophila melanogaster and maintained under strong inbreeding during 80 generations. We assayed 28 microsatellites and detected two mutations. One mutation consisted of a single addition of a dinucleotide repeat and the other was a deletion of five trinucleotide repeats. The average mutation rate was 5.1 x 10(-6), in full agreement with previous estimates from two different sets of mutation accumulation lines.

Animals↗
PubMed2000

Prevalence of Haemophilus influenzae pharyngeal carriers in the school population of Catalonia. Working Group on invasive disease caused by Haemophilus influenzae.

The objective of this study was to determine the prevalence of healthy Haemophilus influenzae (Hi) pharyngeal carriers in a representative sample of the Catalonian school population, as well as the factors associated. A two-stage cluster sampling was carried out. Parents were given a questionnaire to collect information on sociodemographic and epidemiological variables. A pharyngeal swab was performed on children when informed consent was given by parents, and was cultured on chocolate agar with 260 microg/ml bacitracin. Of the 1212 children studied, 316 (26%) H. influenzae carriers were detected: 5 (0.4%) serotype b, 1 (0.08%) serotype c, 6 (0.5%) serotype e, 5 (0.4%) serotype f, and 299 (24.7%) non-typable. Age, gender and geographical location were the only variables associated with H. influenzae carrier status. The prevalence of non-typable H. influenzae carriers was similar to that of studies carried out in other countries, while that of serotype b carriers was similar to the remainder of H. influenzae capsulates, and lower than that described in previous studies. These data are in accordance with the low incidence of the disease observed in our context, although the possibility that the vaccine coverage may have affected the results of this study cannot be dismissed.

Adolescent↗