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Missing data is a common problem in scientific research. The availability of extensive environmental time series is usually laborious and difficult, and sometimes unexpected failures are not detected until samples are processed. Consequently, environmental databases frequently have some gaps with missing data in it. Applying an interpolation method before starting the data analysis can be a good solution in order to complete this missing information. Nevertheless, there are several different approaches whose accuracy should be considered and compared. In this study, data from 6 aerobiological sampling stations were used as an example of environmental data series to assess the accuracy of different interpolation methods. For that, observed daily pollen/spore concentration data series were randomly removed, interpolated by using different methods and then, compared with the observed data to measure the errors produced. Different periods, gap sizes, interpolation methods and bioaerosols were considered in order to check their influence in the interpolation accuracy. The moving mean interpolation method obtained the highest success rate as average. By using this method, a success rate of the 70% was obtained when the risk classes used in the alert systems of the pollen information platforms were taken into account. In general, errors were mostly greater when there were high oscillations in the concentrations of biotic particles during consecutive days. That is the reason why the pre-peak and peak periods showed the highest interpolation errors. The errors were also higher when gaps longer than 5 days were considered. So, for completing long periods of missing data, it would be advisable to test other methodological approaches. A new Variation Index based on the behaviour of the pollen/spore season (measurement of the variability of the concentrations every 2 consecutive days) was elaborated, which allows to estimate the potential error before the interpolation is applied.
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Polen , Bases de Datos Factuales , Estaciones del AñoRESUMEN
Cadaver decomposition islands around animal carcasses can facilitate establishment of various plant life. Facultative scavengers have great potential for endozoochory, and often aggregate around carcasses. Hence, they may disperse plant seeds that they ingest across the landscape towards cadaver decomposition islands. Here, we demonstrate this novel mechanism along a gradient of wild tundra reindeer carcasses. First, we show that the spatial distribution of scavenger faeces (birds and foxes) was concentrated around carcasses. Second, faeces of the predominant scavengers (corvids) commonly contained viable seeds of crowberry, a keystone species of the alpine tundra with predominantly vegetative reproduction. We suggest that cadaver decomposition islands function as endpoints for directed endozoochory by scavengers. Such a mechanism could be especially beneficial for species that rely on small-scale disturbances in soil and vegetation, such as several Nordic berry-producing species with cryptic generative reproduction.
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Dispersión de Semillas , Animales , Aves , Ericaceae , Heces , Conducta Alimentaria , Zorros , Noruega , Reno , SemillasRESUMEN
Air quality is a major issue for humans owing to the fact that the content of particles in the atmosphere has multiple implications for life quality, ecosystem dynamics and environment. Scientists are therefore particularly interested in discovering the origin of airborne particles. A new method has been developed to model the relationship between the emission surface and the total amount of airborne particles at a given distance, employing olive pollen and olive groves as examples. A third-degree polynomial relationship between the air particles at a particular point and the distance from the source was observed, signifying that the nearest area to a point is not that which is most correlated with its air features. This work allows the origin of airborne particles to be discovered and could be implemented in different disciplines related to atmospheric aerosol, thus providing a new approach with which to discover the dynamics of airborne particles.
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Contaminantes Atmosféricos/análisis , Atmósfera/análisis , Monitoreo del Ambiente/métodos , Modelos Teóricos , Humanos , Olea , Polen , España , Análisis Espacio-TemporalRESUMEN
Desert dust intrusions cause the transport of airborne particulate matter from natural sources, with important consequences for climate regulation, biodiversity, ecosystem functioning and dynamics, human health, and socio-economic activities. Some effects of desert intrusions are reinforced or aggravated by the bioaerosol content of the air during these episodes. The influence of desert intrusions on airborne bioaerosol content has been very little studied from a scientific point of view. In this study, a systematic review of scientific literature during 1970-2021 was carried out following the standard protocol Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). After this literature review, only 6% of the articles on airborne transport from desert areas published in the last 50 years are in some way associated with airborne pollen, and of these, only a small proportion focus on the study of pollen-related parameters. The Iberian Peninsula is affected by Saharan intrusions due to its proximity to the African continent and is seeing an increasing trend the number of intrusion events. There is a close relationship among the conditions favouring the occurrence of intrusion episodes, the transport of particulate matter, and the transport of bioaerosols such as pollen grains, spores, or bacteria. The lack of linearity in this relationship and the different seasonal patterns in the occurrence of intrusion events and the pollen season of most plants hinders the study of the correspondence between both phenomena. It is therefore important to analyse the proportion of pollen that comes from regional sources and the proportion that travels over long distances, and the atmospheric conditions that cause greater pollen emission during dust episodes. Current advances in aerobiological techniques make it possible to identify bioaerosols such as pollen and spores that serve as indicators of long-distance transport from remote areas belonging to other bioclimatic and biogeographical units. A greater incidence of desert intrusion episodes may pose a challenge for both traditional systems and for the calibration and correct validation of automatic aerobiological monitoring methods.
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Contaminantes Atmosféricos , Polvo , Humanos , Polvo/análisis , Incidencia , Ecosistema , Monitoreo del Ambiente , Polen/química , Material Particulado , Estaciones del Año , Contaminantes Atmosféricos/análisisRESUMEN
INTRODUCTION: Negative symptoms are nuclear features of schizophrenia that may be present from the onset of the disease. In recent years, it has been described 2 subdomains of negative symptoms: experiential and expressive deficits. The aim of the study is to examine the relationship between negative symptoms and demographic and clinical variables in patients with first-episode psychosis. Also, to explore whether there are differences in the association among these variables and negative symptoms when divided into both subdomains. MATERIAL AND METHODS: A cross-sectional study was performed in 160 patients (52 females and 108 males) with a diagnosis of a first episode psychosis. A questionnaire was administered to collect demographic and clinical variables. RESULTS: A backward stepwise linear regressions analysis was performed in order to observe potential associations between demographic and clinical variables and the presence of negative symptoms. All three models are predicted by worse PSP score, a higher CDSS, a higher disorganized factor score and a lower excited factor score. A longer duration of untreated psychosis (DUP) is associated to a higher score in the experiential deficit subdomain only. CONCLUSIONS: Our work highlights some clinical and phenomenological differences between experiential and expressive deficits. We think that taking into account both subdomains in future studies may lead to more accurate clinical assessment and interventions.
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Trastornos Psicóticos , Esquizofrenia , Masculino , Femenino , Humanos , Estudios Transversales , Trastornos Psicóticos/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológicoRESUMEN
OBJECTIVE: To study the prevalence and the type of childhood trauma (CT) in a first-episode psychosis (FEP) cohort and in a healthy control (HC) sample. To study which clinical and sociodemographic variables in the onset of the FEP are related to having suffered some traumatic experience in childhood. METHOD: 100 FEP patients and 94 HC participated in the study. The Childhood Traumatic Questionnaire (CTQ) was used to evaluate CT. The Positive and Negative Syndrome Scale (PANSS), the Personal and Social Performance (PSP), the Suicide Risk Scale of Plutchik (SRSP), and the Perceived Stress Scale (PSS) were also administered. RESULTS: 61% of FEP patients and 17% of HC reported having experienced some kind of CT. FEP showed more CT than controls in all subscales, except in sexual abuse. The most frequent CT was emotional abuse. For the FEP group, younger age, more years of education, have a first-degree family history, more positive and negative symptoms, more perceived stress and more personal and social functioning were the variables more influenced by having suffered some kind of CT. CONCLUSIONS: There is a high prevalence of CT in FEP patients. Having a first-degree family history of mental illness, more positive symptoms, and more perception of stress at the time of hospital admission were related to having suffered CT. More research is needed to find out the best way to detect CT and its role in psychosis to be able to implement interventions to improve the evolution of these patients.
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Experiencias Adversas de la Infancia , Trastornos Psicóticos , Humanos , Prevalencia , Trastornos Psicóticos/epidemiología , Trastornos Psicóticos/psicología , Encuestas y CuestionariosRESUMEN
Olea pollen concentrations have been studied in relation to the typology of air masses, pollen grain sources and marine nature during advections in a coastal enclave in the south-eastern Iberian Peninsula. Since Spain is the world's leading olive producer, and olive growing extends throughout the Mediterranean basin, this location is ideal for the study of long-distance transport events (LTD) during the main pollen season (MPS). The air masses were classified using the calculation of 48-h back trajectories at 250, 500 and 750 m above ground level using the HYSPLIT model. After that, the frequency of LDT events from Africa and Europe was found to be 8.7% of the MPS days. In contrast, regional air masses were found in 38.6% of the MPS days. This was reflected in pollen concentrations, with significantly higher concentrations (p-value <0.05) on days with regional air masses compared to days with European air masses. Regarding the source areas, the importance of nearby sources with intense olive cultivation was confirmed (i.e., Andalusia). This proximity was relevant beyond the attenuations observed when the advections acquired a marine nature as the air mass back trajectories moved over the sea (p-value <0.001). The review of air mass typologies, source areas and pollen concentrations resulted in establishing peak dates and the detection of LDT associated with these peak dates. Distortions in the typical path of each air mass explained alterations in pollen concentrations on consecutive days. The recirculation and loops of the air mass back trajectories varied the pollen load that every type of air mass could originally contain.
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Contaminantes Atmosféricos , Olea , Contaminantes Atmosféricos/análisis , Alérgenos/análisis , Monitoreo del Ambiente , Polen/química , Estaciones del Año , EspañaRESUMEN
People with first episode of psychosis (FEP) show deficits in social cognition, which have been linked to several sociodemographic, clinical, and psychosocial variables. The aim of the present research was to study social cognition as a whole measure in people with FEP comparing it with a healthy control sample, to study gender differences, and to examine the relationship between sociodemographic, clinical, and psychosocial variables and social cognition in the onset of psychosis. A descriptive, cross-sectional study was performed. The study sample consisted of 63 people (18 females; 45 males) with a diagnosis of FEP and a healthy control group (78 participants: 38 females; 40 males). All the participants were assessed with the social cognitive domain of the MATRICS Consensus Cognitive Battery (MCCB) and several questionnaires related to studied variables. Our results indicated that compared with healthy controls, people with FEP showed social cognition deficits. Furthermore, premorbid IQ was the most relevant variable in social cognition performance in FEP sample. The findings of the present research may be taken into account in clinical practice to improve the intervention with people with FEP.
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Trastornos Psicóticos , Cognición Social , Cognición , Estudios Transversales , Femenino , Humanos , Masculino , Trastornos Psicóticos/epidemiología , Factores SexualesRESUMEN
Our aim was to evaluate whether fatty liver index (FLI) is associated with the risk of type 2 diabetes (T2DM) development within the Spanish adult population and according to their prediabetes status; additionally, to examine its incremental predictive value regarding traditional risk factors. A total of 2260 subjects (Prediabetes: 641 subjects, normoglycemia: 1619 subjects) from the Di@bet.es cohort study were studied. Socio-demographic, anthropometric, clinical data and survey on habits were recorded. An oral glucose tolerance test was performed and fasting determinations of glucose, lipids and insulin were made. FLI was calculated and classified into three categories: Low (< 30), intermediate (30-60) and high (> 60). In total, 143 people developed diabetes at follow-up. The presence of a high FLI category was in all cases a significant independent risk factor for the development of diabetes. The inclusion of FLI categories in prediction models based on different conventional T2DM risk factors significantly increase the prediction power of the models when all the population was considered. According to our results, FLI might be considered an early indicator of T2DM development even under normoglycemic condition. The data also suggest that FLI could provide additional information for the prediction of T2DM in models based on conventional risk factors.
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Glucemia/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Adulto , Biomarcadores/metabolismo , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Our aim is to examine differences in sexual functioning (SF) between patients with drug-naïve first episode psychosis (FEP) and healthy controls (HC). We will also examine correlations between prolactin levels, testosterone levels and psychotic symptomatology with SF from a gender perspective. METHODS: Cross-sectional study. We included 68 FEP patients and 50 HC. A blood sample was extracted. We used the Positive and Negative Syndrome Scale to assess symptom severity, using the five factor structure according to Emsley. The Changes in Sexual Function Questionnaire (CSFQ) was administered. RESULTS: We found significantly better SF in HC than in patients (in CSFQ total score (p = 0.032) and in CSFQ Desire (p = 0.032)). A significant correlation between prolactin or testosterone and SF was not observed. We found a negative significant correlation between the disorganised subscale of the EMSLEY and total CSFQ (p = 0.027; r = -0.329), CSFQ Desire (p = 0.028; r = -0.329) and CSFQ Arousal (p = 0.026; r = -0.332) in the patient sample. In a regression model, we found sex (p = 0.003) and disorganized symptoms (p = 0.034) as significant predictors. CONCLUSIONS: We found evidence for better SF in HC than in FEP patients. We could not confirm an association between prolactin or testosterone and SF. Disorganized symptomatology could be a relevant factor in SF.
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Prolactina/sangre , Trastornos Psicóticos/sangre , Trastornos Psicóticos/diagnóstico , Caracteres Sexuales , Disfunciones Sexuales Fisiológicas/sangre , Disfunciones Sexuales Fisiológicas/diagnóstico , Adolescente , Adulto , Biomarcadores/sangre , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Psicóticos/epidemiología , Disfunciones Sexuales Fisiológicas/epidemiología , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Recent studies have found hyperprolactinemia in first episode psychotic patients that had not previously received antipsychotic treatment (drug-naïve). Our goal was to learn whether there were differences in baseline prolactin concentrations between drug-naïve psychotic patients and healthy controls, as well as to study possible gender differences in the prolactin elevation. A cross-sectional study was conducted that included 61 drug-naïve psychosis patients and 45 healthy controls (aged between 14-55 years old). A blood sample was extracted between 8 and 10 a.m. Prolactin levels and TSH were determined. The Perceived Stress Scale (PSS) was conducted across the sample. This study showed significantly higher levels of prolactin in drug-naïve patients compared to healthy controls. These results were maintained after controlling prolactin levels for sex, age, THC consumption, baseline TSH, and PSS. A significant correlation between prolactin and PSS was not observed. Significant differences in prolactin levels between men and women were not observed. These results are clinically important because if elevated baseline prolactin levels are detected in these patients, it will be necessary to initiate neuroleptics that do not increase this hormone. There was no evidence that stress was related to an increase in prolactin at the onset of psychosis.
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Hiperprolactinemia/psicología , Prolactina/sangre , Trastornos Psicóticos/sangre , Factores Sexuales , Adolescente , Adulto , Antipsicóticos/uso terapéutico , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Hiperprolactinemia/sangre , Masculino , Persona de Mediana Edad , Trastornos Psicóticos/complicaciones , Adulto JovenRESUMEN
Nafcillin imprinted sol-gels were used as specific binding materials for the room temperature phosphorescence (RTP) recognition of nafcillin using a flow injection system. Selective and reversible binding of the template to imprinted sol-gels could be observed by tailoring the hydrophobic/hydrophilic balance of the materials. Also, the possibility of minimizing non-specific interactions was evaluated by end-capping with trimethyl silyl groups. Control experiments were performed with non imprinted reference sol-gels. The recognition mechanism and the analytical potential of these materials for developing stable, selective and sensitive approaches for nafcillin recognition in real samples are outlined.
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Técnicas Biosensibles/instrumentación , Análisis de Inyección de Flujo/instrumentación , Mediciones Luminiscentes/instrumentación , Nafcilina/análisis , Dióxido de Silicio/química , Técnicas Biosensibles/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Análisis de Inyección de Flujo/métodos , Mediciones Luminiscentes/métodos , Óptica y Fotónica/instrumentación , Gel de Sílice , Propiedades de Superficie , TemperaturaRESUMEN
Aerobiological monitoring of Olea europaea L. is of great interest in the Mediterranean basin because olive pollen is one of the most represented pollen types of the airborne spectrum for the Mediterranean region, and olive pollen is considered one of the major cause of pollinosis in this region. The main aim of this study was to develop an airborne-pollen map based on the Pollen Index across a 4-year period (2008-2011), to provide a continuous geographic map for pollen intensity that will have practical applications from the agronomical and allergological points of view. For this purpose, the main predictor variable was an index based on the distribution and abundance of potential sources of pollen emission, including intrinsic information about the general atmospheric patterns of pollen dispersal. In addition, meteorological variables were included in the modeling, together with spatial interpolation, to allow the definition of a spatial model of the Pollen Index from the main olive cultivation areas in the Mediterranean region. The results show marked differences with respect to the dispersal patterns associated to the altitudinal gradient. The findings indicate that areas located at an altitude above 300ma.s.l. receive greater amounts of olive pollen from shorter-distance pollen sources (maximum influence, 27km) with respect to areas lower than 300ma.s.l. (maximum influence, 59km).
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Contaminantes Atmosféricos/análisis , Alérgenos/análisis , Monitoreo del Ambiente/métodos , Olea , Polen , Clima , Región Mediterránea , Rinitis Alérgica Estacional , Estaciones del AñoRESUMEN
Airborne pollen monitoring is an effective tool for studying the reproductive phenology of anemophilous plants, an important bioindicator of plant behavior. Recent decades have revealed a trend towards rising airborne pollen concentrations in Europe, attributing these trends to an increase in anthropogenic CO2 emissions and temperature. However, the lack of water availability in southern Europe may prompt a trend towards lower flowering intensity, especially in herbaceous plants. Here we show variations in flowering intensity by analyzing the Annual Pollen Index (API) of 12 anemophilous taxa across 12 locations in the Iberian Peninsula, over the last two decades, and detecting the influence of the North Atlantic Oscillation (NAO). Results revealed differences in the distribution and flowering intensity of anemophilous species. A negative correlation was observed between airborne pollen concentrations and winter averages of the NAO index. This study confirms that changes in rainfall in the Mediterranean region, attributed to climate change, have an important impact on the phenology of plants.
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Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente , Polen , Alérgenos/análisis , Cambio Climático , Europa (Continente) , Portugal , Estaciones del Año , EspañaRESUMEN
A flow-through optosensor for warfarin is described. The sensor is developed in conjunction with flow analysis systems and uses a commercial bound beta-cyclodextrin material as the sensing phase. A strong fluorescence signal was observed as a result of the formation of an inclusion complex between warfarin and beta-cyclodextrin. The analytical performance characteristics of the proposed sensor for analysis of low levels of warfarin were as follows: the detection limits for continuous and flow injection analysis systems were 2 and 19 ppb, respectively; the observed relative standard deviations at 0. 5 ppm warfarin level were less than 2.3%. A study of the interference of other naphthalenic toxic substances was carried out. The continuous flow method was satisfactorily applied to the determination of the rodenticide in natural waters.
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Ciclodextrinas , Rodenticidas/análisis , Análisis Espectral/instrumentación , Warfarina/análisis , Contaminación Química del Agua/análisis , Agua/química , Agricultura/métodos , Animales , Humanos , Ratas , Sensibilidad y EspecificidadRESUMEN
A study has been made on the spectrophotometric determination of the beta-lactamic antibiotics, amoxicillin and ampicillin, in micellar media using Cu ions as catalyst. Batch and flow injection approaches were compared. Multisimplex design was used to determine the optimal values of the flow injection analysis (FIA) system. Chemical (buffer, pH and Cu(II) concentrations) and physical (flow rate, temperature and reaction coil length) variables were considered. The analytical performance characteristics were as follows: the detection limits for batch and flow-through systems were 2.5 x 10(-7) and 2 x 10(-6) M, respectively, and a relative standard deviation less than 1% was found for both methods. The proposed FIA methodology was satisfactorily applied to the determination of the antibiotics in pharmaceutical formulations.
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Amoxicilina/análisis , Ampicilina/análisis , Antibacterianos/análisis , Análisis de Inyección de Flujo/métodos , Calibración , Cobre/química , Concentración de Iones de Hidrógeno , Micelas , Espectrofotometría/instrumentación , Espectrofotometría/métodos , Tensoactivos/química , TemperaturaRESUMEN
A survey on the quality of drugs-of-abuse testing in European laboratories was performed in 1993 (Part I) and 1994 (Part II). A total of 195 laboratories participated in Part I and 228 in Part II. There were 154 repeater laboratories. In each part of the survey, six urine samples were sent for analysis under routine conditions. A set of reference materials, including deuterated drug-standard solutions, was provided in Part II of the survey for optimization of analytical procedures. Screening for groups of substances was mainly performed by immunological techniques. Rates of false-positive (FP) results were 0 and 0.5%, respectively, in Parts I and II, and rates of false-negative (FN) results were 7.7% in Part I and 3.4% in Part II. Identification and quantitation of specific substances was mainly carried out by chromatographic methods, particularly gas chromatography coupled to mass spectrometry. Application of chromatographic methods showed a lack of sensitivity (14.9% and 16.7% FN in Parts I and II, respectively) and a lack of specificity (0.8% FP in Part I versus 1.1% in Part II). Repeater laboratories improved their results (17.4% FN in Part I versus 14.2% Part II). The improvement of repeater laboratories emphasizes the need of external quality control programs. The experience is being used as a basis for a recommendation on drug-testing guidelines by a group of European toxicologists.
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Técnicas de Laboratorio Clínico/normas , Unión Europea , Detección de Abuso de Sustancias/normas , Recolección de Datos , Reacciones Falso Positivas , Cromatografía de Gases y Espectrometría de Masas , Humanos , Drogas Ilícitas , Inmunoensayo , Control de CalidadRESUMEN
We investigated the usefulness of immunological methods for presumptive detection of stimulants found in sports drug testing. The ingestion of substances that show no cross-reactivity in tests commercially available for the detection of amphetamines can produce positive results in the urine. Human metabolism contributes to the positive results of some urine samples when the parent compound does not cross-react with the antibodies of the assay. Urine samples from healthy volunteers given stimulants were tested by chromatographic methods and by two different fluorescence polarization immunoassays (FPIA) from Abbott Laboratories for the analysis of amphetamines. According to the results obtained, we classified stimulants into four groups: detectable stimulants that gave rise to amphetamine by human metabolism (group 1); detectable ephedrines and related compounds, appearing in the urine either as parent compounds or originated by metabolism (group 2); detectable stimulants that displayed actual cross-reactivity with amphetamine tests (group 3); and stimulants not detected by FPIA (group 4). Most of the true doping cases due to the ingestion of stimulants may be detected by FPIA. The specificity of the results may be increased by combining immunological assays with different antibodies.
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Estimulantes del Sistema Nervioso Central/orina , Doping en los Deportes , Anfetamina/administración & dosificación , Anfetamina/orina , Anfetaminas/administración & dosificación , Anfetaminas/orina , Especificidad de Anticuerpos , Depresores del Apetito/administración & dosificación , Depresores del Apetito/metabolismo , Estimulantes del Sistema Nervioso Central/administración & dosificación , Cromatografía de Gases , Reacciones Cruzadas , Efedrina/administración & dosificación , Efedrina/orina , Inmunoensayo de Polarización Fluorescente , Humanos , Masculino , Metanfetamina/administración & dosificación , Metanfetamina/análogos & derivados , Metanfetamina/orina , Reproducibilidad de los Resultados , Relación Estructura-Actividad , Teofilina/administración & dosificación , Teofilina/análogos & derivados , Teofilina/orinaRESUMEN
Nineteen patients with pneumonia caused by Legionella, who did not need to be admitted to ICU were treated with 500 mg/day of azithromycin. The etiological diagnosis was made retrospectively by detecting Legionella pneumophila in the urine of nine patients and/or by serology (seroconversion or single titer 1/256) in 19 cases. None of them met the criteria for ICU admittance nor had received prior treatment with antibiotics which were potentially active against L. pneumophila. Serology tests and radiography of the thorax were carried out on all the patients in the study during their convalescence period. The average age (+/- SD) of the group was 58.5 +/- 16.2 years. The average respiratory frequency (+/- SD) 26 +/- 6 breaths per minute; the radiologic extension was of one lobule in 18 cases and two lobules in one case. No patients showed bilateral disease. Arterial gasometry (FiO2 0.21) showed a pO2 average of (+/- SD) 53 +/- 14 mmHg and the hemogram an average of 6.700 leukocytes/mm3 (range: 4,200-41-800). All the patients progressed favorably. The average duration of fever was 1.8 days; the average stay (+/- SD) was 6.1 +/- 2 days. The treatment was well tolerated. One month after discharge radiographies were clear for all patients. There were no relapses. In conclusion, 3-day administration of azithromycin was found to be a useful guide in the treatment of community acquired pneumonia caused by Legionella in patients whose clinical situation does not require ICU administration and allows for oral administration.