In situ electromagnet with active cooling for real-time magneto-optic Kerr effect spectroscopy.

We present a compact in situ electromagnet with an active cooling system for use in ultrahigh vacuum environments. The active cooling enhances the thermal stability and increases the electric current that can be applied through the coil, promoting the generation of homogeneous magnetic fields, required for applications in real-time deposition experiments. The electromagnet has been integrated into a reflectance difference magneto-optic Kerr effect (RD-MOKE) spectroscopy system that allows the synchronous measurement of the optical anisotropy and the magneto-optic response in polar MOKE geometry. Proof of principle studies have been performed in real time during the deposition of ultra-thin Ni films on Cu(110)-(2 × 1)O surfaces, corroborating the extremely sharp spin reorientation transition above a critical coverage of 9 monolayers and demonstrating the potential of the applied setup for real-time and in situ investigations of magnetic thin films and interfaces.

Efficacy of needleless transcutaneous electroacupuncture in synchronization with breathing for symptomatic idiopathic gastroparesis: A blinded and controlled acute treatment trial.

BACKGROUND: Needleless transcutaneous electroacupuncture (TEA) improves nausea and myoelectrical activity in diabetic gastroparesis (GP). Synchronized TEA (STEA), which combines synchronized breathing with TEA, is more potent than TEA in enhancing vagal activity in healthy subjects. AIMS: To investigate whether STEA improves symptoms, electrogastrogram (EGG) and vagal activity in idiopathic gastroparesis (IGP). METHODS: Eighteen IGP subjects underwent 2 randomized visits (sham at non-acupoints or real STEA at acupoints) consisted of a 30-minute baseline, an Ensure challenge to provoke nausea, followed by 60-minute treatment with sham or real STEA, and 15-minute observation period. Severity of nausea, EGG, and vagal activity (based on electrocardiogram and serum Pancreatic Polypeptide, PP) were recorded. RESULTS: In sham or STEA, the nausea scores of 2.7 ± 0.5 and 1.9 ± 0.5 at fasting baseline, respectively, increased to 5.9 ± 0.4 and 5.8 ± 0.3 during Ensure test (P < .05, vs baseline), subsequently reduced to 3.4 ± 0.6 with sham or 3.6 ± 0.6 with STEA, respectively (P < .05, vs Ensure period). Experiments with sham and STEA started with similar % of normal waves on EGG (66.4 ± 3.9 and 61.8 ± 3.0, respectively); decreased to 63. 5 ± 4.1 and 58.2 ± 2.8 during the Ensure test. After STEA, there was ~24% increase in % of normal waves, significantly different from the sham (6.0%) (P < .01). In sham or STEA, vagal activity was identical at baseline and after the Ensure. STEA induced a 3-fold increase in vagal activity compared with sham (P < .01). Ensure increased serum PP levels, and both treatments decreased the PP CONCLUSIONS: In IGP, STEA is not superior to Sham in decreasing nausea, but is more effective in improving gastric dysrhythmia.

Response to pneumococcal polysaccharide vaccine in children with asthma, and children with recurrent respiratory infections, and healthy children.

BACKGROUND: To analyse specific immune response to the 23-valent pneumococcal polysaccharide vaccine by measuring pneumococcal antibodies in children with asthma and with respiratory recurrent infection (RRI) as compared to healthy children. METHODS: The study included 60 children, divided into three groups: 20 with asthma, 20 with RRI, and 20 healthy controls. Post-vaccination specific IgG antibodies against 10 pneumococcal serotypes (S1, S3, S4, S5, S6B, S9V, S14, S18C, S19F, and S23F) contained in the 23-valent pneumococcal polysaccharide vaccine (PPV) were measured. A specific IgG concentration ≥1.3µg/mL was considered a protective response to the vaccine. For statistical analysis, levels of specific IgG antibodies against each of the 10 pneumococcal serotypes were compared across the three groups of children using the x(2) test. RESULTS: All of the children showed antipneumococcal antibody levels >1.3µg/mL for over 70% of the serotypes, considered within the normal range of response. Average IgG antibody levels and percentages of children protected were statistically comparable among the three groups studied. CONCLUSION: The asthmatic children without RRI had pneumococcal antibody levels and percentages of serotype-specific protection to PPV comparable to those of healthy children. Asthmatic children with recurrent infections should be evaluated for specific antibody deficiency (SAD). Because asthma patients are at high risk for invasive pneumococcal infections, it would be worthwhile to explore systematic administration of PPV in children over the age of two years who have not received a pneumococcal conjugate vaccine, considering the positive response to PPV reported here.

Polarization-dependent differential reflectance spectroscopy for real-time monitoring of organic thin film growth.

By monitoring the reflectance of a sample surface during deposition of a thin organic film, one can obtain information with submonolayer resolution in real-time. A special kind of optical spectroscopy is Differential Reflectance Spectroscopy (DRS), which compares the reflectance before and during deposition of a thin film or any other change of the surface optical properties. In this work, we present an extended DRS setup that allows monitoring simultaneously both linear polarization states (s and p) of the reflected light. We implement polarization-dependent DRS to monitor the growth of perflouropentacene thin films on a Ag(110) single crystal. The setup allows us to deduce the optical anisotropy of the sample and, in particular, the preferred orientation of the molecules on the surface.

Specific antibody deficiency with normal immunoglobulin concentration in children with recurrent respiratory infections.

BACKGROUND: Response to polysaccharide antigens is a test to evaluate the immunological competence of children with recurrent respiratory infections (RRI) of unknown cause and no other immune system abnormality. In order to detect specific antibody deficiency (SAD), a group of children with RRI without other immunodeficiency were prospectively studied. METHODS: We included 20 children (12 male), age range 3-14 years, with six or more annual episodes of respiratory infections (RI); one or more monthly episodes of RI during the winter months; or three or more annual episodes of lower RI. The children were immunised with 23-valent polysaccharide anti-pneumococcal vaccine, and ELISA was used to measure anti-polysaccharide IgG antibody levels for 10 pneumococcal serotypes at baseline (T0), and 45 days (T1) and one year post-immunisation (T2). Post-immunisation response above 1.3 µg/ml for more than 50% of the serotypes was considered normal for children 2-5 years, and for more than 70% of the serotypes in children older than 5 years. RESULTS: At T1 19/20 children showed a normal response for their age, and only one patient showed a deficient response, suggestive of classic moderate SAD. At T2, 8/20 patients showed deficient responses, suggestive of impaired persistence of specific antibodies. There was a noteworthy association between deficient response and asthma and allergic rhinitis. CONCLUSIONS: We propose first ruling out local or systemic causes, then performing serum immunoglobulin IgM, IgG, IgA, IgE and IgG subclass levels, and finally measuring response to polysaccharide pneumococcal antigens for detection of SAD.

Morphological characteristics of the temporomandibular joint articular surfaces in patients with temporomandibular deisorders / Características morfológicas de las superficies articulares de la articulación temporomandibular de pacientes con trastornos temporomandibulares

The knowledge of the anatomical characteristics of the temporomandibular joint (TMJ) articular surfaces is essentital to enable physicians and dentists to recognize the morphological changes that occur in this articulation in patients with temporomandibular disorders (TMD). Several researchers associate the TMD with changes of TMJ articular surfaces. The careful identification of bone changes related to TMJ is critical, since these abnormalities are associated with signs and symptoms of TMD and the knowledge of TMD signs and symptoms is fundamental for correctly diagnosing and for adequate treatment planning. The aim of this study was to evaluate the morphological characteristics of the TMJ articular surfaces in patients with TMD diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). In addition, therelationship between increasing age-osteoarthrosis was evaluated. For the sample we selected 19 patients, 17 female and 2 male, referred to the "Unidad de Trastornos Cráneo Cérvico Mandibulares (UCRACEM) - Universidad de Talca, Chile". The imaging assessment was carried out by Cone-Beam Computed Tomography (CBCT). In the imaging analysis of the articular surfaces 11 joints (28.94 percent) showed normal morphology. The bone changes found were: sclerosis, flattening, erosion, osteoarthrosis, osteophytes, subcondral cysts. We found statistically significant difference between increasing age-osteoarthrosis (p=0.00). Considering our results we concluded that bone changes of the TMJ articular surfaces in patients with TMD are very common, with sclerosis as the most frequent finding. It was also possible to conclude that there was a significant association between increasing age-osteoarthrosis.

El conocimiento de las características anatómicas de las superficies articulares de la articulación temporomandibular (ATM) es fundamental para que clínicos y odontólogos reconozcan las alteraciones morfológicas que ocurren en la articulación de pacientes con trastornos temporomandibulares (TTM). Diversos investigadores asocian los TTMs con alteraciones en las superficies articulares de la ATM. La identificación de los cambios óseos relacionados con la ATM es crítica, ya que estos se asocian a signos y síntomas de TTM, y el conocimiento de estos es fundamental para el correcto diagnóstico y adecuada planificación de tratamiento. El objetivo fue analizar las características morfológicas de las superficies articulares de la ATM en pacientes con diagnóstico de TTM, diagnosticado de acuerdo a los Criterios Diagnósticos para Investigación de los Trastornos Temporomandibulares (CDI/TTM), junto con analizar la relación existente entre incremento de edad-osteoartrosis. Fueron seleccionados 19 pacientes, 17 mujeres y 2 hombres, de la Unidad de Trastornos Cráneo Cérvico Mandibulares (UCRACEM) - Universidad de Talca, Chile. La evaluación imagenológica se realizó mediante el examen de Tomografía Computarizada Cone-Beam (TCCB). En el análisis de las superficies articulares, 11 (28,94 por ciento) presentaron morfología normal. Los cambios óseos encontrados fueron: esclerosis, aplanamiento de la cabeza de la mandíbula, erosión, osteoartrosis, osteofitos y quiste subcondral. Hubo relación estadística significativa entre incremento de edad-osteoartrosis (p=0,00). Nuestros hallazgos nos permiten concluir que los cambios óseos en las caras articulares de la ATM en pacientes con TTM son frecuentes, y la esclerosis el hallazgo más común. También se encontró asociación entre incremento de edad y osteoartrosis.

Percepción del nivel cognoscitivo sobre manejo postural continuo en cuidadores de pacientes en silla de ruedas / Perception of cognition level about continuous postural management in caregivers of patients in wheelchairs

Introducción: Los pacientes con alteraciones neurológicas severas dependen del cuidado de terceros, muchas veces son las familias quienes asumen este rol, pero se desconoce cuánto logran integrar del manejo postural continuo. Objetivo: Determinar la percepción del nivel cognoscitivo de los cuidadores, en relación al manejo postural continuo, de pacientes en silla de ruedas, que asisten al Instituto Teletón Concepción, durante el año 2011. Pacientes y Métodos: Se realizó un estudio cualitativo fenomenológico con muestra de casos tipos en 8 cuidadores, que permitió profundizar en las experiencias individuales de estos, a través de entrevistas semi-estructuradas. Se realizó análisis semántico estructural sobre el discurso de los cuidadores. Resultados: Se estableció los códigos principales bajo los cuales los cuidadores comprenden el manejo postural continuo, el cual se entendió por el concepto de alineación corporal, la condición muscular del paciente y las expectativas de rehabilitación. Hay un mayor reconocimiento de los padres a la información entregada por sus pares, dándole mayor valor emocional. Las experiencias particulares de cada cuidador pueden ser una fuente positiva de refuerzo del programa de manejo postural continuo. Conclusiones: Los cuidadores refieren poseer amplios conocimientos del manejo postural continuo, pero no son capaces de detallar los aspectos básicos del mismo, evidenciando una falta de integración del conocimiento en esta área.

Introduction: Patients with severe neurological disorders depend on a third party for their care. Usually it is within their own families, that someone takes over that role, however, it is unknown to what extent they are able to integrate “continuous postural management”. Objective: To determine caregivers’ cognitive perception level with regards to “continuous postural management”, of patients who use wheelchairs and who attended Teletón Institute at Concepción, Chile, during the year 2011. Patients and Method: A phenomenological qualitative research using type cases samples in 8 caregivers was carried out. This made possible to go in depth with their individual experiences by conducting semi-structured interviews. A structural semantic analysis about the caregivers’ speech was done. Outcomes: Main codes under which caregivers understand “continuous postural management” were established. This was understood as the concept of body or corporal alignment, patients’ muscular condition and rehabilitation expectancies. There is greater acknowledgment from parents regarding information provided by their peers, which adds greater emotional value. Therefore, each caregiver’s individual experience may become a constructive strengthening source for the “continuous postural management” program. Conclusions: Caregivers reported having broad knowledge regarding “continuous posture management”, however they were unable to provide details about its basic characteristics, thus showing lack of knowledge integration in this area.

Transmitted drug-resistance in human immunodeficiency virus-infected adult population in El Salvador, Central America.

El Salvador harbours one of the largest Central American human immunodeficiency virus (HIV) epidemics, but few studies have analysed it in depth. Here, we describe the presence of transmitted drug resistance (TDR) and HIV variants in the HIV-infected adult population in El Salvador. Dried blood spots from 119 HIV-infected antiretroviral-naive adults attended in El Salvador were collected in 2011. The TDR was assessed according to the list recommended by the WHO. HIV-1 variants were described using phylogeny. Pol sequences could be amplified in 88 patients (50.6% men), with a mean age of 35 years. Almost all (96.7%) were infected with HIV through sexual practice and 58.7% were recently diagnosed. The mean CD4(+) count was 474 cells/mm(3) and 43.1% and 15.5% of patients showed moderate (<500 CD4 cells) or severe (<200) immune suppression, respectively. HIV-1 viral load was >100 000 copies/mL in 24.7% of patients and <2000 copies/mL in 9.1%. Five samples (5.7%) harboured any TDR mutation: 2.3% for nucleoside reverse transcriptase inhibitor (NRTI) and non-nucleoside reverse transcriptase inhibitor (NNRTI), and 1.4% for protease inhibitor (PI). All showed only one TDR single-class resistance mutation: M184I (two cases) for NRTI, K101E and K103N for NNRTI and L23I for PI. All viruses excepting one (URF_BG) belonged to subtype B. No phylogenetic TDR networks were found. In conclusion, we report a TDR prevalence of 5.7% in El Salvador, lower than in other Central American studies. Periodical studies are essential to monitor and prevent TDR emergence in low-income and middle-income regions. Also, more efforts are needed to promote early diagnosis and prevention of infection in El Salvador.

Hallazgos en radiografías panorámocas de adultos mayores de Talca, Chile / Radiological findings in panoramic radiograhs of elderly people of Talca, Chile

El objetivo del presente estudio fue determinar la prevalencia de hallazgos radiográficos en pacientes mayores de 60 años, atendidos en el Servicio de Radiología del Centro de Clínicas Odontológicas de la Universidad de Talca entre los meses de marzo y octubre del año 2010. Se evaluaron 190 radiografías panorámicas digitales de pacientes mayores de 60 años de edad. Se determinó la presencia de lesiones radiolúcidas (RL), lesiones radiopacas (RO), restos radiculares (RR), lesiones apicales (LA), cuerpos extraños (CE), dientes incluidos (DI), calcificaciones en tejidos blandos (CTB) y calcificaciones del complejo estilohioídeo (CCE). El 58,9 % del total de la muestra tuvo hallazgos. En pacientes edéntulos totales, el 51,4% de las radiografías tuvieron algún hallazgo, mientras que en edéntulos parciales, el porcentaje el 60,6% presentaron hallazgos radiográficos. Estos en el total de la muestra se encontraron en orden decreciente fueron CCE 25,26%; CTB 24,21%; LA 19%; RO 11,05%; RR 7,36%; PI 4,21%; RL 3,68%. No se encontró cuerpos extraños. La mayoría de los hallazgos se encontró de manera única (57%). Nuestros resultados sugieren que sería adecuado solicitar una radiografía panorámica antes de iniciar el tratamiento rehabilitador de un paciente adulto mayor, para obtener información que permita la realización de un tratamiento odontológica de forma segura

The aim of this study was to determine prevalence of radiological findings in digital panoramic radiographs of 60-year-old patients and more, treated in Radiological Service of Universidad de Talca`s Dental Clinical Center during the period between March and October of year 2010. 190 digital panoramic radiographs from elderly patients were observed. Radiolucent lesions (RL), radiopaque lesions (RO), periapical radiolucent lesions (LA), root fragments (RF), foreign bodies (FB), unerupted teeth (UT), soft tissue calcifications (STC) and calcified stylohyoid complex (CSC) were assessed. 58,9 % of full sample showed radiological findings. In edentulous mouths, 51,4% of radiographs had findings, whereas in partially edentulous, percentage of Rx with findings was 60,6%. Radiological findings of full sample in decreasing order were as next: CSC 25,26%; STC 24,21%; LA 19%; RO 11,05%; RF 7,36%; UT 4,21%; RL 3,68%. Foreign bodies were not found. Radiological findings were seen multiple in 43%. Our results suggest that prescribe a panoramic radiograph before starting a rehabilitation treatment to an elderly patient, would be beneficial in order to obtain useful information for safer dental treatments

Necrosis-inducing proteins of Rhynchosporium commune, effectors in quantitative disease resistance.

The barley pathogen Rhynchosporium commune secretes necrosis-inducing proteins NIP1, NIP2, and NIP3. Expression analysis revealed that NIP1 transcripts appear to be present in fungal spores already, whereas NIP2 and NIP3 are synthesized after inoculation of host plants. To assess the contribution of the three effector proteins to disease development, deletion mutants were generated. The development of these fungal mutants on four barley cultivars was quantified in comparison with that of the parent wild-type strain and with two fungal strains failing to secrete an "active" NIP1 avirulence protein, using quantitative polymerase chain reaction as well as microscopic imaging after fungal green fluorescent protein tagging. The impact of the three deletions varied quantitatively depending on the host genotype, suggesting that the activities of the fungal effectors add up to produce stronger growth patterns and symptom development. Alternatively, recognition events of differing intensities may be converted into defense gene expression in a quantitative manner.

Lung involvement in rheumatologic diseases in children.

BACKGROUND: Lung involvement in rheumatologic disease in children has been described with low frequency. OBJECTIVE: To describe the lung function test and the radiological findings in a group of paediatric patients with rheumatologic diseases. METHODS: Descriptive study. Pulmonary function was evaluated with spirometry, carbon monoxide diffusing capacity, blood arterial gas at rest and post exercise in addition to chest radiography and high resolution computed tomography were performed in children with rheumatologic disease. RESULTS: Of the fourteen patients studied: 11 were diagnosed with juvenile idiopathic arthritis (JIA), two with systemic lupus erythematosus (SLE), and one with juvenile dermatomyositis (JDM). Mean age: 13 years (range 7-18 years). Nine females, duration of disease 4 ± 2.8 years (range 1-11 years). Four patients had any grade of abnormalities in one or more lung function tests and/or radiological test. CONCLUSION: We recommend routine checks of pulmonary function in all patients with rheumatologic diseases even in the absence of respiratory symptoms.

Primary immunodeficiency diseases in Latin America: proceedings of the Second Latin American Society for Immunodeficiencies (LASID) Advisory Board.

Early diagnosis and appropriate therapy are essential for the best prognosis and quality of life in patients with primary immunodeficiency diseases (PIDDs). Experts from several Latin American countries have been meeting on a regular basis as part of an ongoing effort to improve the diagnosis and treatment of PIDD in this region. Three programmes are in development that will expand education and training and improve access to testing facilities throughout Latin America. These programmes are: an educational outreach programme (The L-Project); an immunology fellowship programme; and the establishment of a laboratory network to expand access to testing facilities. This report provides the status of these programmes based on the most recent discussions and describes the next steps toward full implementation of these programmes.

Apoptosis, shape change and reactive oxygen species generation in human neutrophils exposed to olanzapine, an a typical antipsychotic drug

The effects of olanzapine (OLZ) on the viability and functioning of human polymorphonuclearcells (PMNs) are clearly opposite to those previously reported forclozapine (CLZ). In fact, after 4- or 24-h-treatment with 20-50 μM OLZ, a significant inhibition of the respiratory burst in PMNs activated with opsonized zimosanor phorbol myristate acetate (PMA) was observed, whereas the burst provoked byformyl-methionyl-leucyl-phenylalanine (fMLP) was only inhibited at 50 μM OLZ.Under the same conditions, spontaneous apoptosis was accelerated at 20-50 μMOLZ, while the exogenous addition of H2O2 resulted in the PMN apoptosis beingdose-dependently inhibited by OLZ in the entire range of concentrations. However,when H2O2 was intracellularly generated by treatment with PMA, the induced apoptosis was only decreased at 2 μM OLZ. Absorbance scans revealed that OLZis able to react with equimolar quantities of either H2O2 or HOCl. These results suggest that OLZ inhibits both ROS-induced PMN apoptosis and respiratory burst due to extracellular scavenging of released ROS.

Los efectos de olanzapine (olz) sobre la viabilidad y el funcionamiento de células humanas polimorfonucleares (pmn, por sus siglas en inglés) claramente son opuestosa los señalados para la clozapine (clz). En efecto, después de 4-24 h de tratamiento con 20-50 μM olz, se observó una inhibición significativa del estallido respiratorio en pmn activados con zimosan o con forbol acetato miristato, mientras que la inhibición provocada por el formil-metionil-leucil-fenilalanina fue sólo inhibida a 50μM de olz. En las mismas condiciones, la apoptosis espontánea se aceleró con 20-50μM olz, mientras que la adición exógena de H2O2 dio lugar a la apoptosis de pmn en dosis dependiente inhibida por olz en el rango entero de concentraciones. Sin embargo, cuando se generó H2O2 intracelular por tratamiento con pma, la apoptosis inducida se disminuyó solamente con 2 μM olz. Las exploraciones de los espectros de absorbancia revelaron que olz puede reaccionar con cantidades equimolares de H2O2 o de HOCL. Estos resultados sugieren que olz inhibe ambos tipos de apoptosis de pmn (la inducida por especies reactivas oxigenadas y por estallido respiratorio debido a atrapadores extracelulares de estas especies reactivas oxigenadas).

Historia del Instituto Nacional del Tórax / History of the Instituto Nacional del Tórax

El Instituto Nacional del Tórax fue creado oficialmente el 23 de Agosto de 1954, bajo el impulso y talento del Profesor Héctor Orrego Puelma, quien fuera nombrado posteriormente Maestro de la Especialidad por nuestra Sociedad.El Instituto nació en 1954, a partir del Servicio de Broncopulmonar del Hospital del Salvador, en un principio, sus principales funciones estaban centradas en brindar atención a algunas patologías respiratorias, como la tuberculosis, y capacitar médicos en esta área.Su organización era muy sencilla, pues existían dos grandes servicios clínicos: el de Medicina, a cargo del Profesor Dr. Héctor Orrego Puelma, y el de Cirugía, a cargo del Profesor Dr. Armando Alonso Vial. La dotación de camas daba cuenta del perfil epidemiológico del país de entonces: 102 camas se destinaban a enfermos de tuberculosis, 90 camas para patologías respiratorias no TBC y 100 camas para cirugía de pulmón, en total 292 camas. En sus dos primeros años de funcionamiento, el Instituto recibió 6.068 nuevos pacientes, de los cuales el 25% presentaba una TBC activa

Controlled aggregation of magnetic ions in a semiconductor: an experimental demonstration.

The control on the distribution of magnetic ions into a semiconducting host is crucial for the functionality of magnetically doped semiconductors. Through a structural analysis at the nanoscale, we give experimental evidence that the aggregation of Fe ions in (Ga,Fe)N and consequently the magnetic response of the material are affected by the growth rate and doping with shallow impurities.

Efficacy of pyriprole topical solution against the cat flea, Ctenocephalides felis, on dogs.

Three studies evaluating various aspects of the performance of pyriprole against the cat flea, Ctenocephalides felis, on dogs demonstrated that 12.5% pyriprole applied as a spot-on provides rapid, long-lasting efficacy against adult cat fleas, even under severe flea challenge. Speed of kill data indicate treatment with this product can interrupt an already established adult flea infestation, whereas monthly treatment can prevent reinfestation. Pyriprole disrupts the flea life cycle by killing adult fleas before they lay eggs for at least 30 days after treatment. The residual effect of pyriprole on debris from treated dogs (dander, hair, scales, and flea feces) resulted in a decreased ability of cat flea larvae to complete development to the adult stage for 2 weeks after application. Based on the results of these studies, 12.5% pyriprole represents a valuable new tool in the control of the cat flea, C. felis, on dogs.

Observation of strong-coupling effects in a diluted magnetic semiconductor Ga1-xFexN.

The giant Zeeman splitting of free excitons is measured in Ga(1-x)Fe(x)N. Magneto-optical and magnetization data imply the ferromagnetic sign and a reduced magnitude of the effective p-d exchange energy governing the interaction between Fe(3+) ions and holes in GaN, N_{0}beta(app)=+0.5+/-0.2 eV. This finding corroborates the recent suggestion that the strong p-d hybridization specific to nitrides and oxides leads to significant renormalization of the valence band exchange splitting.

Changes in the survival of patients with systemic lupus erythematosus in childhood: 30 years experience in Chile.

The objective of this study was to analyse the survival rate and cause of death in children with systemic lupus erythematosus (SLE) during the past 30 years in Chile. A retrospective analysis was performed between 1969 and 2000 on patients attending pediatric rheumatology centres in Santiago, Chile. Survival and causes of death in 31 children followed from 1969 to 1980 fulfilling the 1982 American College of Rheumatology criteria for SLE and treated with oral steroids were compared with 50 other patients who were treated with oral steroids and an aggressive treatment of IV bolus of cyclophosphamide (38 patients) and azathioprine (12 patients). Global survival at five and 10 years follow-up for the patients studied from 1969 to 1980 was 68 and 40%, respectively. During the second study period these values were significantly improved and global survival reached 95% at five years and 90% at 10 years follow-up (P < 0.05). Survival at 10 years follow-up for patients with lupus nephropathy increased from 28% (study period 1964-1980) to 86% (study period 1984-2000). Twelve children died (38%) during the 1964-1980 study period. The causes of death were six due to kidney failure, three due to infectious conditions and another three of unknown causes. During the 1980-2000 study period mortality reached 6% (three cases), two cases died of a lupus flare-up and one case due to infection. In the last three decades, we have seen an important increase in the survival of children with SLE, especially in those patients with renal involvement. Management with immunosuppressive drugs, such as IV cyclophosphamide or azathioprine has changed the prognosis in these children. These results demonstrate that our children with SLE increased their life expectancy but are now faced with new types of morbidity because of the sequelae related to the disease itself.

Paralytic shellfish toxins in the chocolata clam, Megapitaria squalida (Bivalvia: Veneridae), in Bahia de La Paz, Gulf of California

Occurrence and toxic profiles of paralytic shellfish toxins (PST) in the chocolata clam Megapitaria squalida were investigated. From December 2001 to December 2002, 25 clams were obtained monthly from Bahía de La Paz, Gulf of California. Additionally, net (20 µm) and bottle phytoplankton samples were also collected to identify toxic species. Toxins were analyzed by HPLC with post-column oxidation and fluorescence detection. Toxicity in the clam was low and varied from 0.14 to 5.46 µg/STXeq/100 g. Toxicity was detected in December, March, April, June, and August. Toxin profile was composed mainly by STX, GTX2, GTX3, dcGTX2, dcGTX3, C2, dcSTX and B1. Gymnodinium catenatum was the only PST-producing dinoflagellate identified in the phytoplankton samples throughout the study period. G. catenatum was observed mainly in net samples from December 2001 to December 2002; however, in bottle samples, G. catenatum was only observed in five months. Highest abundance (2 600 cells l-1 ) was observed in March and the lowest (160 cells l-1 ) in June. G. catenatum mainly formed two-cell chains and rarely four or eight. The presence of PST in net phytoplankton samples support the fact that G. catenatum is the main source of PST in the clams. This study represents the first report of PST toxins in the chocolata clam from Bahía de La Paz

Se investigó la ocurrencia así como los perfiles de toxinas paralíticas (PST) en la almeja chocolata Megapitaria squalida (Sowerby, 1835), de la cual se recolectaron mensualmente 25 ejemplares de diciembre del 2001 a diciembre del 2000 en La Bahía de La Paz, Golfo de California. Simultáneamente, se obtuvieron muestras de fitoplancton de botella y de red (20 µM) para identificar especies tóxicas, así como para detectar la presencia de toxinas paralíticas. Las toxinas se analizaron por HPLC con una oxidación post-columna y detección fluorescente. La toxicidad en las almejas fue baja y varió de 0.14 a 5.46 µg/STXeq/100 g y se detectó en diciembre, marzo, abril, junio y agosto. El perfil de toxinas estuvo compuesto principalmente por STX, GTX2, GTX3, dcGTX2, dcGTX3, C2, dcSTX y B1, siendo similar al perfil observado en las muestras de red. Gymnodinium catenatum fue la única especie productora de toxinas paralíticas identificada en las muestras de fitoplancton a través de todo el período del estudio. G. catenatum se observó principalmente en muestras de red correspondientes a diciembre 2001-diciembre 2002; sin embargo, en muestras de botella, G. Catenatum solo fue observado en cinco meses. La abundancia más alta (2 600 céls l-1 ) se encontró en marzo y la más baja (160 céls l-1 ) en junio. G. catenatum se presentó formando cadenas de dos células y raramente de cuatro u ocho. La presencia de toxinas en las muestras de red donde esta especie es frecuente, apoya la idea de que G. catenatum sea la fuente principal de PST en las almejas. Este estudio representa el primer reporte de toxinas paralíticas en la almeja chocolata de Bahía de La Paz