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D Núñez

Publications and source records attributed to D Núñez.

16 recordsLinked to original sources
PubMed2005

Operational and microbiological aspects of a bioaugmented two-stage biotrickling filter removing hydrogen sulfide and dimethyl sulfide.

A two-stage biotrickling filter was developed for removing dimethyl sulfide (DMS) and hydrogen sulfide (H2S). The first biotrickling filter (ABF) was inoculated with Acidithiobacillus thiooxidans and operated without pH control, while the second biotrickling filter (HBF) was inoculated with Hyphomicrobium VS and operated at neutral pH. High DMS elimination capacities were observed in the HBF (8.2 g DMS m(-3) h(-1) at 90% removal efficiency) after 2 days. Maximal observed elimination capacities were 83 g H2S m(-3) h(-1) (100% removal efficiency) and 58 g DMS m(-3) h(-1) (88% removal efficiency) for the ABF and the HBF, respectively. The influence of a decreasing empty bed residence time (120 down to 30 sec) and the robustness of the HBF towards changing operational parameters (low pH, starvation, and DMS and H2S peak loadings) were investigated. Suboptimal operational conditions rapidly resulted in lower DMS removal efficiencies, but recovery of the HBF was mostly obtained within a few days. The H2S removal efficiency in the ABF, however, was not influenced by varying operational conditions. In both reactors, microbial community dynamics of the biofilm and the suspended bacteria were investigated, using denaturing gradient gel electrophoresis (DGGE). After a period of gradual change, a stable microbial community was observed in the HBF after 60 days, although Hyphomicrobium VS was not the dominant microorganism. In contrast, the ABF biofilm community was stable from the first day and only a limited bacterial diversity was observed. The planktonic microbial community in the HBF was very different from that in the biofilm.

Acidithiobacillus thiooxidans↗
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↗
PubMed1990

[The relationships between cholesterol and arterial pressure in the Málaga-86 study. Something more than a casual association?].

The frequent association of this vascular risk factors implies not just a potentiation of the vascular risk, but also the need for a wider therapeutical approach on this patients not only regarding the control of the arterial hypertension but also other risk factors. After a cross-sectional study of the prevalence of various vascular risk factors in the province of Málaga (Spain), we analysed the results as for the cholesterolemia and blood pressure in normotensives and hypertensives. In the hypertensive population we observed a tendency to present a higher levels of cholesterol as well as a higher prevalence of hypercholesterolemia (p less than 0.001); on the other hand, hypercholesterolemic people versus normocholesterolemics showed similar data related to their blood pressure and prevalence of hypertension. Finally we discussed the likely etiopathogenetic interrelationships between both vascular risk factors.

Adult↗
PubMed1989

Effects of bile salts on energy metabolism and acid secretion by the isolated toad gastric mucosa.

The effects of bile salts on energy metabolism and acid secretion were investigated in the amphibian gastric mucosa in vitro. Serosal exposure to deoxycholate (0.2-2 mM), cholate (2-8 mM), or taurocholate (4-80 mM), at pH 7.4, decreased acid secretion depending on the concentration and time of exposure. Mucosal application of cholate and taurocholate at pH 5.6 caused a more pronounced reduction in the apparent rate of acid secretion. Oxygen uptake and substrate oxidations were significantly inhibited by bile salts in a dose-dependent manner. At pH 7.4, 1 mM deoxycholate inhibited the respiration by 49% and the rates of oxidation by 51%, 52%, 78%, 74%, and 54% of control values, for glucose, pyruvate, succinate, acetate, and butyrate, respectively. Cholate and taurocholate were found to be less potent than deoxycholate. Tissue adenosine triphosphate concentration was decreased by 13%, 57%, and 67% with 0.5, 1, and 2 mM deoxycholate, respectively. We believe the impairment of energy metabolism could be involved in the mechanism of bile salt injury to the gastric mucosa.

Animals↗
PubMed1986

Review of computed tomography findings in thrombosis of the major abdominal venous pathways.

Computed tomography is commonly the first diagnostic modality to detect venous thrombosis. The relatively constant location and anatomic relations of the major abdominal veins allow for their proper recognition and differentiation from other tubular structures. Whether the occlusion is secondary to blood clot or tumor extension, the vessels demonstrate a characteristic appearance. The presence of adjacent tumor mass is the single most important factor to differentiate the two types of thrombi. Invaluable aid is provided by computed tomography in the management of this clinical situation. Uncommonly, the diagnosis remains unclear and venography must be done. Selected examples of major abdominal venous thrombosis are presented.

Abdomen↗
PubMedDate not supplied

[The diagnosis of traumatic cervical lesions: a decade of evidence-based change].

The growing awareness of the need for emergency centers specializing in the care of trauma patients, together with advances in diagnostic imaging technology, have led to the occasional indiscriminate use of diagnostic methods to the detriment of ordering diagnostic tests based on the risk of fracture and of the clinical examination itself. In many institutions, this practice is carried out without appropriate controls and without analyzing the risks and benefits of a particular clinical conduct. This is particularly true in cases of multiple trauma with suspected traumatic lesions of the cervical spine. For many years, radiological examination was based on plain-film radiography, with CT playing a complementary role. Over the last decade, since the introduction of helical CT, and more recently multidetector CT scanners, the diagnostic approach has undergone rapid, significant changes. This article summarizes the experience based on publications centered on establishing the diagnostic effectiveness of CT in comparison to plain-film radiography and the importance of recognizing risk factors when determining the diagnostic strategy. On the other hand, the importance of avoiding unnecessary tests and excessive radiation in providing appropriate and efficient medical care is stressed. In general, the evidence indicates that CT should be the first-line approach in high-risk patients and plain-film radiography should be reserved for the initial evaluation of patients with a low risk of traumatic lesions.

Cervical Vertebrae↗
PubMedDate not supplied

[Present situation and future perspectives of the epidemic of HIV and AIDS in Spain].

Until 1997 Spain was the European country with the highest incidence of AIDS, due mainly to transmission between users of injected drugs. Since early 1990 there has been a fall in the rate of diagnoses of HIV infection in the Spanish autonomous communities where this information is available, and in 2004 this rate was situated below that of several western European countries. New infections in users of intravenous drugs have declined, and although heterosexual transmission has not undergone significant changes, it has become the prime cause of new HIV infections. The rate of diagnoses of HIV has fallen in both the indigenous population and immigrants; however, demographic changes have meant an increase in the percentage of HIV diagnoses in immigrants. In homosexual men there have been descriptions of a recent increase in the incidence of syphilis and gonococcus, which are a warning of possible increases in the transmission of HIV in this group. The number of people who live with HIV in Spain remains between 100,000 and 150,000 (2.4 to 3.6 per 1,000 inhabitants). In spite of the improvement in prognosis due to antiretroviral treatments, there are annually in Spain over 2,000 cases of AIDS (4.8 per 100,000 inhabitants) and over 1,600 deaths from AIDS (3.8 per 100,000). One third of the people who developed AIDS in 2004 had not until then been diagnosed with HIV, which prevented starting the antiretroviral treatment in time.

Acquired Immunodeficiency Syndrome↗