RESUMEN
In this work, the aerobic biodegradability of the process water (PW) produced by hydrothermal carbonization (HTC) of dewatered anaerobic digested sludge and the toxicity assessment in regard to the heterotrophic activated biomass of a conventional activated sludge systems, are described. Such assessments are not yet reported in other scientific papers, so this paper seeks to contribute to the increase of knowledge regarding the valorization of the HTC process applied in a wastewater treatment plant (WWTP). For such purpose, two different respirometric techniques were applied - multi-OUR respirometry and manometric respirometry. PW resulted highly biodegradable: 83% of total COD was biodegradable, with a 58% of readily biodegradable (rbCOD) fraction. The BOD5/COD ratio was 0.42. Further, it was characterized by a high concentration of volatile fatty acids (VFAs) (i.e. 2031 mg/L), of which the major constituent was acetic acid (i.e. 80%), an easily degradable intermediate of many biological processes. Both the respirometric techniques showed that the assessed PW, after being diluted accordingly with the WWTP real operational conditions, did not imply short-term toxic effects on the activated sludge, neither using fresh biomass nor keeping the same one. According to these results, the recirculation of PW at the water line of WWTPs represents a promising approach not affected by specific toxicity issues, especially when the HTC process is integrated into a WWTP scheme.
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Aguas del Alcantarillado , Agua , Biomasa , Ácidos Grasos Volátiles , Aguas ResidualesRESUMEN
The impact force experienced by a runner when his/her foot makes contact with the ground has been the subject of much research. This force is called the ground reaction force (GRF), and has been measured by several groups. In parallel with this, mathematical models have been developed to simulate GRFs in order to investigate various effects on this, such as the parameters of the human body and types of running shoe soles. Lumped parameter models have been developed by several researchers with limited success, because they are either constrained to model translational motion, or become complicated if they include rotational motion. This paper proposes a new approach based on modes of vibration, which encompasses the simplicity of the lumped parameter approach, without the motion constraints. The GRF is decomposed into contributions due to the various vibration modes of the system. To achieve this, a linear system is required, so a Zener model, which is used to model viscoelastic materials, is employed as the ground reaction model. The modal modelling approach is described in detail using established lumped parameter models used to predict the GRF. It is then applied to four experimental data sets from the literature, where it is shown that at most three modes are required to model GRF data accurately. Two of these modes are oscillatory modes and one is a non-oscillatory exponentially decaying mode. In general, it is shown that the modal model can capture the dynamics of each measured GRF independently of speed and running style.
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Marcha , Carrera , Fenómenos Biomecánicos , Femenino , Pie , Humanos , Masculino , ZapatosRESUMEN
We calculate auroral energy flux and Joule heating in the high-latitude ionosphere for 27 geomagnetically active days using two-dimensional maps of field-aligned currents determined by the Active Magnetosphere and Planetary Response Experiment. The energy input to the ionosphere due to Joule heating increases more rapidly with geomagnetic activity than that due to precipitating particles. The energy flux varies more smoothly with time than Joule heating, which is impulsive in nature on time scales from minutes to tens of minutes. These impulsive events correlate well with recoveries in the Sym-H index, with the maximum correlation when compared to Sym-H recoveries 70 min later. Because of prior studies that have associated transient recoveries of Sym-H with substorm expansions, the delay found here suggests that dissipation of energy in the ionosphere occurs during the substorm growth phase prior to the release of magnetic energy caused by diversion of tail currents.
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Dendritic regression of striatal spiny projection neurons (SPNs) is a pathological hallmark of Parkinson's disease (PD). Here we investigate how chronic dopamine denervation and dopamine replacement with L-DOPA affect the morphology and physiology of direct pathway SPNs (dSPNS) in the rat striatum. We used a lentiviral vector optimized for retrograde labeling (FuG-B-GFP) to identify dSPNs in rats with 6-hydroxydopamine (6-OHDA) lesions. Changes in morphology and physiology of dSPNs were assessed through a combination of patch-clamp recordings and two photon microscopy. The 6-OHDA lesion caused a significant reduction in dSPN dendritic complexity. Following chronic L-DOPA treatment, dSPNs segregated into two equal-sized clusters. One group (here called "cluster-1"), showed sustained dendritic atrophy and a partially normalized electrophysiological phenotype. The other one ("cluster-2") exhibited dendritic regrowth and a strong reduction of intrinsic excitability. Interestingly, FosB/∆FosB induction by L-DOPA treatment occurred preferentially in cluster-2 dSPNs. Our study demonstrates the feasibility of retrograde FuG-B-GFP labeling to study dSPNs in the rat and reveals, for the first time, that a subgroup of dSPNs shows dendritic sprouting in response to chronic L-DOPA treatment. Investigating the mechanisms and significance of this response will greatly improve our understanding of the adaptations induced by dopamine replacement therapy in PD.
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Neuronas/patología , Enfermedad de Parkinson/fisiopatología , Degeneración Estriatonigral/fisiopatología , Animales , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Discinesia Inducida por Medicamentos/metabolismo , Femenino , Levodopa/farmacología , Ratones , Ratones Transgénicos , Neostriado/metabolismo , Fenotipo , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D1/metabolismoRESUMEN
Papillomas are uncommon tumors of the sinonasal tract histologically derived from the Schneiderian membrane. Three distinctive variants are described, the exophytic, the inverting and the oncocytic types. On physical examination, their appearance varies from exophytic-fungiform seen in the exophytic variant, to polypoid-papillary in both the inverting and oncocytic variant. The presence of an asymptomatic mass or epistaxis and unilateral nasal obstruction are the typical presenting symptoms. Clinically they tend to recur and, although benign, they may erode the bone laminas by pressure, especially the inverting type, causing proptosis and other co-morbidities. Malignant transformation is seen both synchronously, on a pre-existing papilloma, and metachronously after several recurrences of papilloma. Schneiderian papillomas are at a date a topic of controversy regarding their etiology, pathogenesis and biological behavior. Furthermore, histologic criteria to assess dysplasia and malignant transformation are ill-defined. The present study aims to comparatively review the histologic types of papillomas, their etiology, the currently available criteria for malignant transformation, their treatment and prognosis.
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Neoplasias Nasales , Papiloma , Transformación Celular Neoplásica , Humanos , Mucosa Nasal , Recurrencia Local de Neoplasia , Neoplasias Nasales/diagnóstico , Neoplasias Nasales/etiología , Neoplasias Nasales/terapia , Papiloma/diagnóstico , Papiloma/etiología , Papiloma/terapia , PronósticoRESUMEN
A two-stage thermophilic anaerobic digestion process for the concurrent production of hydrogen and methane through the treatment of the source-sorted organic fraction of municipal solid waste was carried out over a long-term pilot scale experience. Two continuously stirred tank reactors were operated for about 1 year. The results showed that stable production of bio-hythane without inoculum treatment could be obtained. The pH of the dark fermentation reactor was maintained in the optimal range for hydrogen-producing bacteria activity through sludge recirculation from a methanogenic reactor. An average specific bio-hythane production of 0.65 m(3) per kg of volatile solids fed was achieved when the recirculation flow was controlled through an evaporation unit in order to avoid inhibition problems for both microbial communities. Microbial analysis indicated that dominant bacterial species in the dark fermentation reactor are related to the Lactobacillus family, while the population of the methanogenic reactor was mainly composed of Defluviitoga tunisiensis. The archaeal community of the methanogenic reactor shifted, moving from Methanothermobacter-like to Methanobacteriales and Methanosarcinales, the latter found also in the dark fermentation reactor when a considerable methane production was detected.
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Reactores Biológicos , Aguas del Alcantarillado , Residuos Sólidos , Eliminación de Residuos Líquidos/métodos , Anaerobiosis , Archaea/clasificación , Archaea/genética , Archaea/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Calor , Filogenia , Proyectos Piloto , Factores de TiempoRESUMEN
Studies on the detection of animal by-products in poultry meat are rare and practically nonexistent in chicken meat. With the development of the technique of stable isotopes for traceability purposes and the certification of broiler diet patterns, it has been necessary to know the behavior of the isotopic signature of different tissues in birds, in case of a potential replacement of a diet containing animal ingredients with a strictly vegetable one and vice versa. Thus, this study, carried out at the São Paulo State University, Botucatu Campus, Brazil, aimed to evaluate meat from the breast, thigh, drumstick, and wings to trace the presence of poultry offal meal (OM) in broiler feed using the analysis of stable isotopes of carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) by mass spectrometry. In total, 720 one-d-old chicks were distributed into 6 groups: vegetable diet (VD) from 1 to 42 d; 8% poultry offal meal (OM) diet from 1 to 42 d; VD from 1 to 21 d and 8% OM diet from 22 to 42 d; VD from 1 to 35 d and 8% OM diet from 36 to 42 d; 8% OM diet from 1 to 21 d and VD from 22 to 42 d; and 8% OM diet from 1 to 35 d and VD from 36 to 42 d. Through the analysis of C and N, it is possible to trace the use of OM in broiler feeding when this ingredient is part of the feeding throughout the breeding phase or when it substitutes a strictly VD even up to 35 d. When an OM diet is substituted by a VD, the animal ingredient has to be part of the feeding for 21 d or longer to be detected by this method.
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Alimentación Animal/análisis , Carbono/metabolismo , Dieta/veterinaria , Nitrógeno/metabolismo , Productos Avícolas/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Isótopos de Carbono/metabolismo , Pollos , Masculino , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Isótopos de Nitrógeno/metabolismoRESUMEN
Neuropeptide Y (NPY) has been extensively studied in relation to anxiety and depression but of the seven NPY receptors known to date, it is not yet clear which one is mainly involved in mediating its effects in emotional behavior. Mice lacking the NPY-Y2 receptors were previously shown to be less anxious due to their improved ability to cope with stressful situations. In the present study, the behavioral phenotype including the response to challenges was analyzed in NPY-Y2 knockout (KO) mice backcrossed in to congenic C57BL/6 background. In the elevated plus-maze (EPM) and the forced swim test (FST), the anxiolytic-like or antidepressant-like phenotype of the NPY-Y2 KO mice could not be confirmed, although this study differs from the previous one only with regard to the genetic background of the mice. In addition, no differences in response to acute stress or to the antidepressant desipramine in the FST were detected between wild type (WT) and NPY-Y2 KO animals. These results suggest that the genetic background of the animals appears to have a strong influence on the behavioral phenotype of NPY-Y2 KO mice. Additionally, to further characterize the animals by their biochemical response to a challenge, the neurochemical changes induced by the anxiogenic compound yohimbine were measured in the medial prefrontal cortex (mPFC) of NPY-Y2 KO and compared to WT mice. Dopamine (DA) levels were significantly increased by yohimbine in the WT but unaffected in the KO mice, suggesting that NPY-Y2 receptor exerts a direct control over both the tonic and phasic release of DA and that, although the anxiety-like behavior of these NPY-Y2 KO mice is unaltered, there are clear modifications of DA dynamics. However, yohimbine led to a significant increase in noradrenaline (NA) concentration and a slight reduction in serotonin concentration that were identical for both phenotypes.
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Ansiedad/genética , Conducta Animal/fisiología , Encéfalo/metabolismo , Receptores de Neuropéptido Y/genética , Antagonistas de Receptores Adrenérgicos alfa 2/farmacología , Animales , Ansiedad/metabolismo , Encéfalo/efectos de los fármacos , Química Encefálica , Dopamina/metabolismo , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microdiálisis , Norepinefrina/metabolismo , Fenotipo , Receptores de Neuropéptido Y/deficiencia , Receptores de Neuropéptido Y/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Yohimbina/farmacologíaRESUMEN
This research was conducted in Porto Alegre, Rio Grande do Sul, with a sample of battered women selected from a government shelter called the "Casa Viva Maria". We analyzed data on 110 women staying at the shelter during the previous two years (January 1996-June 1998). The profile of the women was as follows: abused women were young (mean age 29 years), all had low socioeconomic status, 12% were illiterate, 21% were black, 80% reported frequent abuse by their partners, and 18% had returned to violent homes. The researchers visited 34 former lodgers from the shelter and invited them to participate in a series of evaluation workshops. A total of 118 persons, including mothers and children, attended three evaluation meetings. During this process, researchers encouraged participants to express opinions, perceptions, and feelings about their past experience in the shelter and their own concept of violence. Finally, a focal group was organized with the "Viva Maria" staff members. Female workers reported how their job had been helpful for their personal development and had helped change their own lives.
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Atención a la Salud , Violencia Doméstica , Casas de Salud , Salud de la Mujer , Adolescente , Adulto , Brasil , Niño , Violencia Doméstica/psicología , Femenino , Grupos Focales , Humanos , Masculino , Persona de Mediana Edad , Maltrato ConyugalRESUMEN
BACKGROUND: The aim of this study was to evaluate the appropriateness and utility rates of echocardiograms performed in 309 patients in an outpatient clinical setting. METHODS: Data were collected by means of a questionnaire filled in by the cardiologists who performed the examinations. Appropriateness was evaluated according to international guidelines and scored as class I: appropriate, class II: doubtful appropriateness, class III: inappropriate; the exam was deemed useful if it was able to influence the clinical decision-making; normalcy rate was also checked. The relationship between both the referring physicians and motivation of the exam and its appropriateness, and the relationship between appropriateness and both the normalcy rate and utility of the exam were assessed. RESULTS: An echocardiogram was requested by the cardiologist in 46% of patients; the more common reasons for the exam were arterial hypertension (26%), cardiac murmur (18%), palpitations (15%), and known coronary artery disease (10%). The echocardiogram was appropriate (class I) in 25% of patients, doubtfully appropriate (class II) in 39% of patients and inappropriate (class III) in 36% of patients. The appropriateness rate between the cardiologists was similar to that of other prescribing clinicians (p = NS). The highest class III rate was found in patients with hypertension, while the highest class I rate was found in patients with a cardiac murmur (p < 0.01). Normalcy rate was lower in class I than in class II and III exams (p < 0.001). The utility rate was higher in class I (76%) than in class II (13%) and III (< 1%) exams (p < 0.01). CONCLUSIONS: International guidelines can be used effectively and safely to identify (not to prescribe) the useless echocardiograms.
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Ecocardiografía/estadística & datos numéricos , Revisión de Utilización de Recursos/métodos , Distribución de Chi-Cuadrado , Costos y Análisis de Costo , Ecocardiografía/economía , Humanos , Italia , Encuestas y CuestionariosRESUMEN
A 53-year-old woman being treated for a vaginal yeast infection experienced ecchymosis. Laboratory evaluation revealed a prolonged prothrombin time. It is possible that the bleeding was due to an interaction between warfarin and miconazole. Health care professionals should be aware of the potential for drug interactions with vaginally administered miconazole, especially in women receiving anticoagulation therapy.
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Anticoagulantes/efectos adversos , Antifúngicos/efectos adversos , Miconazol/efectos adversos , Vaginitis/tratamiento farmacológico , Warfarina/efectos adversos , Administración Intravaginal , Antifúngicos/administración & dosificación , Sinergismo Farmacológico , Equimosis/inducido químicamente , Femenino , Humanos , Miconazol/administración & dosificación , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial , SupositoriosRESUMEN
BACKGROUND: Microalbuminuria could be a possible coronary risk factor: AIM: To study the association between microalbuminuria, serum lipid levels and coronary heart disease in non-insulin-dependent diabetics. PATIENTS AND METHODS: We studied 104 non-insulin-dependent diabetics, who were separated in four groups according to the presence of microalbuminuria, defined as a 24 h albumin excretion of 30-300 mg/24 h and according the history of coronary artery disease. Total, HDL and LDL cholesterol, triglycerides, alpha, beta, prebeta lipoproteins, lipoprotein (a), apoproteins A and B were measured in all. RESULTS: Twenty patients with and 32 without coronary artery disease had normal albumin excretion and the same number of patients had a urinary albumin 30-300 mg/24 h. All four groups were comparable in terms of metabolic control, nutritional status, blood pressure and creatinine levels. Patients with coronary artery disease had higher urinary albumin excretion than patients without the disease 91 (32-173) and 34 (5-97) mg/24 h respectively p < 0.01. Patients with coronary artery disease and microalbuminuria had higher triglycerides, beta, pre beta lipoproteins, Apo B, Lp(a) and lower Apo B and alpha lipoproteins. This group also had a higher frequency of abnormal pre beta and alpha lipoprotein levels, when compared with coronary patients with normal albumin excretion. In coronary patients there was a positive association between urinary albumin levels and triglycerides (r = 0.24), pre beta lipoproteins (r = 0.27) and Apo B (r = 0.3); there was also a negative association with HDL cholesterol (r = 0.25) and alpha lipoproteins (r = -0.41). CONCLUSIONS: In this group of non-insulin-dependent diabetics, an association among microalbuminuria, abnormal serum lipid levels and coronary artery disease was detected.
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Albuminuria/etiología , Enfermedad Coronaria/etiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Lípidos/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Humanos , Persona de Mediana Edad , Factores de Riesgo , Triglicéridos/sangreRESUMEN
A cDNA clone encoding a transglutaminase (TGase) was isolated from a cDNA library prepared from the larval stage of Ciona intestinalis. The cDNA sequence has an open reading frame encoding a protein of 696 amino acids and is about 36% identical to 11 other TGase sequences. In addition, the critical residues thought to form the catalytic center are conserved. The Ciona TGase (CiTGase) has an extension of 39 amino acids in the NH2-terminal region similar to that reported for keratinocyte TGases. A phylogenetic analysis among other types of TGases demonstrated that CiTGase represents a new type of the enzyme.
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Ciona intestinalis/enzimología , Transglutaminasas/química , Transglutaminasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Northern Blotting , Ciona intestinalis/genética , Clonación Molecular , Secuencia Conservada , ADN Complementario , Evolución Molecular , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Larva/enzimología , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN , Transglutaminasas/metabolismoRESUMEN
Huntington's disease (HD) is a neurodegenerative disorder associated with CAG repeat expansion. We measured transglutaminase (TGase) activity in lymphocytes from 35 HD patients and from healthy individuals to ascertain whether it was altered in this condition. TGase activity was above maximum control levels in 25% of HD patients; it was correlated with the age of the patient and inversely correlated with the CAG repeat length. These results suggest that: (1) HD could be biochemically heterogeneous, and (2) the length of the CAG repeat expansion/TGase ratio could be important in the manifestation of HD.
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Enfermedad de Huntington/genética , Transglutaminasas/genética , Adulto , Edad de Inicio , Anciano , Femenino , Humanos , Enfermedad de Huntington/enzimología , Linfocitos/enzimología , Masculino , Persona de Mediana Edad , Secuencias Repetitivas de Ácidos Nucleicos , Transglutaminasas/metabolismoAsunto(s)
Antagonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/uso terapéutico , Angina de Pecho/tratamiento farmacológico , Bradicardia/prevención & control , Ensayos Clínicos como Asunto , Regulación hacia Abajo/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Humanos , Lipoproteínas/sangre , Lipoproteínas/efectos de los fármacosRESUMEN
Transglutaminase inhibitor (1,3,4,5-tetramethyl-2-[(2-oxopropyl)thio]imidazolium chloride or L-682777) affected the appearance of the fertilization envelope (FE) and subsequent development in Sphaerechinus granularis and Arbacia punctulata in a concentration-dependent manner. Abnormalities were first visible in forming FE's at the lowest concentration (0.001 mM) of the inhibitor used. The wrinkled appearance of FE's suggested that the treatment prevented the I-T transition, whereas the finding of numerous denuded cells and empty FE's indicated that the inhibitor acted by rendering the FE's very fragile. Cell division by the 2-cell stage was also affected by this active-site-directed transglutaminase inhibitor. With 0.05 mM of the inhibitor, about 50% of all cells were polynucleated. In view of earlier findings that other transglutaminase inhibitors can produce abnormalities with regard to FE wrinkling and deranged cell division, it can be suggested that different forms of transglutaminases might be involved at various stages in embryonic development.
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Fertilización , Óvulo/crecimiento & desarrollo , Transglutaminasas/antagonistas & inhibidores , Animales , División Celular , Equinodermos , Femenino , Imidazoles/farmacología , Óvulo/enzimologíaRESUMEN
Among sea anemone neurotoxins, calitoxin, recently isolated from Calliactis parasitica, is a highly toxic peptide of 46 amino acids (aa), whose sequence differs greatly from that of all sea anemone toxins isolated so far. In this study, two genes (clx-1 and clx-2) coding for two highly homologous calitoxins were isolated and characterized from a C. parasitica genomic library. The clx-1 gene encodes the already known calitoxin sequence, named CLX-I, whereas a single bp substitution in the coding region of clx-2 is responsible for a single Glu6-->Lys replacement in a new peptide named CLX-II. The structural organization of the two genes is very similar: two introns and three exons, whose sequences are highly homologous for clx-1 and clx-2 (95% identity). The open reading frame (ORF) of both clx-1 and clx-2 codes for a precursor peptide of 79 aa, whose N-terminus has the feature of a single peptide, while the C-terminus corresponds to the sequences of mature CLX-I and CLX-II. The finding that a pair of basic aa is located upstream from the sequence of both mature toxins strongly suggests that proteolytic events, at specific cleavage sites, are responsible for the release of neurotoxins from their respective precursor molecules.
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Venenos de Cnidarios/genética , Anémonas de Mar/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Venenos de Cnidarios/biosíntesis , ADN/genética , Cartilla de ADN , Datos de Secuencia Molecular , Neurotoxinas/biosíntesis , Poli A/aislamiento & purificación , Poli A/metabolismo , Reacción en Cadena de la Polimerasa , ARN/aislamiento & purificación , ARN/metabolismo , ARN Mensajero , Mapeo Restrictivo , Homología de Secuencia de Ácido NucleicoRESUMEN
The chemistry, pharmacology, pharmacokinetics, clinical efficacy, adverse effects, and dosage of sotalol hydrochloride are reviewed. The chemical name of sotalol hydrochloride is 4'-[1-hydroxy-2-(isopropylamino)ethyl]methanesulfonanilide monohydrochloride. Sotalol is a class III antiarrhythmic that prolongs the action potential and refractoriness of cardiac tissue and has potent nonselective beta-blocking activity. Sotalol is well absorbed after oral administration. The pharmacokinetics of sotalol can be described by an open, linear, two-compartment model. The drug is eliminated primarily by the kidneys; mean elimination half-life is 12 hours. Sotalol has been found to be effective in controlling life-threatening ventricular arrhythmias, including sustained ventricular tachycardia, ventricular fibrillation, and premature ventricular complexes. Although sotalol has FDA-approved labeling for use in the treatment of ventricular arrhythmias only, it is also effective against a variety of supraventricular arrhythmias. Noncardiac adverse effects include fatigue, impotence, depression, headache, nausea, diarrhea, and increased triglyceride levels. Cardiovascular adverse effects include atrioventricular block, bradycardia, hypotension, exacerbation of heart failure, and polymorphic ventricular tachycardia. Overall, 11-21% of patients experience adverse effects; 6-18% of these patients have reactions serious enough to warrant the discontinuation of sotalol therapy. The initial dosage of oral sotalol hydrochloride in adults is 80 mg twice daily or 160 mg once daily; the dosage can be increased every three to four days in increments of 40-160 mg/day to a maximum of 480 mg/day. Sotalol is useful in the control of intractable, life-threatening ventricular arrhythmias, as well as a variety of supraventricular arrhythmias, in patients who do not respond to or are intolerant of more conventional antiarrhythmics.