The role of executive functions, social cognition and intelligence in predicting social adaptation of vulnerable populations.

This study sought to evaluate the roles of and interactions between cognitive processes that have been shown to exhibit impact from socioeconomic status (SES) and living conditions in predicting social adaptation (SA) in a population of adults living in socially vulnerable conditions. Participants included 226 people between the ages of 18 and 60 who have been living in vulnerable contexts throughout life in Santiago, Chile. Data was collected through a battery of psychological assessments. A structural equation model (SEM) was implemented to examine the interrelationships among cognitive and social variables. Results indicate a significant relationship between executive function (EF) and SA through both social cognition (SC) and intelligence. Theory of Mind (ToM), a component of SC, was shown to exhibit a significant relationship with affective empathy; interestingly, this was negatively related to SA. Moreover, fluid intelligence (FI) was found to exhibit a positive, indirect relationship with SA through crystallized intelligence (CI). Evaluation of these results in the context of research on the impacts of SES and vulnerable living conditions on psychological function may allow for the development of more effective clinical, political, and social interventions to support psychosocial health among socially vulnerable populations.

Sistemas de activación y de inhibición de conducta y su relación con el funcionamiento ejecutivo en excombatientes irregulares del conflicto armado colombiano / Behavior activation and inhibition systems and their correlation with executive functioning in ex-combatants of the Colombian armed conflicto / Sistemas de ativação e de inibição de conduta e sua relação com o funcionamento executivo em ex-combatentes irregulares do conflito armado colombiano

Objetivo: Explorar la relación entre los sistemas de activación de conducta (SAC) / sistema de inhibición de conducta (SIC) y funciones ejecutivas (FE) en excombatientes del conflicto armado colombiano. Metodología: Estudio observacional, exploratorio, con muestra no aleatoria de 39 excombatientes del programa de la Alta Consejería de la Presidencia para la Reintegración, residentes en Antioquia-Colombia, edad 35±7.6 años, 87.2% hombres, y escolaridad 10±2.8 grados; comparados con un grupo control de 14 no combatientes (edad 33±6.1 años, 71.4% hombres y escolaridad 10±2.7 grados). Se les administró un cuestionario de SAC/SIC, usando la sensibilidad a la recompensa (SR) y la sensibilidad al castigo (SC). Para la FE se aplicó la prueba Ineco Frontal Screening (IFS). Resultados: Hubo alteraciones específicas de la FE: en la ejecución de instrucciones conflictivas (IC), memoria de trabajo verbal (MTV) y control inhibitorio verbal (CIV). Se evidenciaron correlaciones directas, con coeficientes de moderados a altos entre el SAC (SR) y la capacidad de abstracción CA, el control motor inhibitorio (CMI), la MTV, la memoria de trabajo espacial (MTE) y el funcionamiento ejecutivo global (IFSTOT). Conclusiones: Los excombatientes presentaron un rendimiento inferior en la memoria de trabajo verbal y el control inhibitorio verbal, lo que impacta las capacidades de anticipación, establecimiento de metas, diseño de planes, iniciación de conductas voluntarias y el control inhibitorio. Lo anterior puede generar la toma de decisiones equivocadas.

Objective: To explore the correlations between behavior activation and inhibition systems (BAS/ BIS) and executive functions in ex-combatants of the Colombian armed conflict. Methodology: Observational, exploratory study, with a sample of 39 ex-combatants belonging to the "High Counseling of the Presidency for Reintegration" program, residents in Antioquia-Colombia, with an average of 35±7.6 year of age, 87.2% were males, with school grades of10±2.8; who were compared with a control group of 14 non-combatants, with ages between 33±6.1 years-old, 71.4% were males, and with school grades 10±2.7. The BAS/ BIS questionnaire was administered in order to score the Reward Sensitivity (RS) and Punishment Sensitivity (PS). The EF was evaluated with INECO-Frontal Screening (IFS). Results: There were specific alterations of EF in the execution of conflicting instructions (CI), verbal working memory (MTV) and verbal inhibitory control (CIV). Direct correlations, moderate to high coefficients between SAC (SR) and CA abstraction capacity, CMI inhibitory motor control, MTV, spatial working memory (MTE), and global executive functioning (IFSTOT). Conclusions: Colombian ex-combatants have lower performance in verbal working memory and verbal inhibitory control, which would affect anticipation, goal setting, plan design, initiation of voluntary behaviors and inhibitory control, which generates generation of wrong decisions.

Objetivo: Explorar a relação entre os sistemas de ativação de conduta (SAC) / sistema de inibição de conduta (SIC) e funções executivas (FE) em ex-combatentes do conflito armado colombiano. Metodologia: Estudo observacional, exploratório, com amostra não aleatória de 39 ex-combatentes do programa da Alto Conselho da Presidência para a Reintegração, residentes em Antioquia-Colômbia, idade 35±7.6 anos, 87.2% homens, e escolaridade 10±2.8 graus; comparados com um grupo controle de 14 não combatentes (idade 33±6.1 anos, 71.4% homens e escolaridade 10±2.7 graus). Se lhes administrou um questionário de SAC/SIC, usando a sensibilidade à recompensa (SR) e a sensibilidade ao castigo (SC). Para a FE se aplicou a prova Ineco Frontal Screening (IFS). Resultados: Houve alterações específicas da FE: na execução de instruções conflitivas (IC), memória de trabalho verbal (MTV) e controle inibitório verbal (CIV). Se evidenciaram correlações diretas, com coeficientes de moderados a altos entre o SAC (SR) e a capacidade de abstração CA, o controle motor inibitório (CMI), a MTV, a memória de trabalho espacial (MTE) e o funcionamento executivo global (IFSTOT). Conclusões: Os ex-combatientes apresentaram um rendimento inferior na memória de trabalho verbal e o controle inibitório verbal, o que impacta as capacidades de antecipação, estabelecimento de metas, desenho de planos, iniciação de condutas voluntárias e o controle inibitório. O anterior pode gerar a toma de decisões equivocadas.

Neurocognitive reorganization of emotional processing following a socio-cognitive intervention in Colombian ex-combatants.

Ex-combatants often exhibit atypical Emotional Processing (EP) such as reduced emphatic levels and higher aggressive attitudes. Social Cognitive Training (SCT) addressing socio-emotional components powerfully improve social interaction among Colombian ex-combatants. However, with narrow neural evidence, this study offers a new testimony. A sample of 28 ex-combatants from Colombian illegal armed groups took part in this study, split into 15 for SCT and 13 for the conventional program offered by the Governmental Reintegration Route. All of them were assessed before and after the intervention with a protocol that included an EP task synchronized with electroencephalographic recordings. We drew behavioral scores and brain connectivity (Coherency) metrics from task performance. Behavioral scores yielded no significant effects. Increased post-intervention connectivity in the delta band was observed during negative emotional processing only SCT group. Positive emotions exposed distinctive gamma band connectivity that differentiate groups. These results suggest that SCT can trigger covert neurofunctional reorganization in ex-combatants embarked on the reintegration process even when overt behavioral improvements are not yet apparent. Such covert functional changes may be the neural signature of compensatory mechanisms necessary to reshape behaviors adaptively. This novel framework may inspire cutting-edge translational research at the crossing of neuroscience, sociology, and public policy-making.

Validation of the Extreme Experiences Scale (EX2) for Armed Conflict Contexts.

Psychological approaches to the study of armed conflict have focused on analyzing post-traumatic stress outcomes, and on evaluating the intensity of exposure to violent confrontation. Nevertheless, psychometrically valid tools required for measuring these traumatic experiences are scarce To validate the Extreme Experiences scale (EX2) for armed conflict contexts for its use in Colombia, and to provide a framework for validation in conflict contexts around the world This Cross-sectional aims to validate the scale with 187 participants, study of validate with 187 participants, comprising population with high exposure to conflict (former combatants and a set of armed conflict victims) and low conflict-exposed individuals (control group). Structures of two domains and 18 items were confirmed: Direct Extreme Experiences (dEX2) and Indirect Extreme Experiences (iEX2); these dimensions were also validated by expert judgment, producing 14-item version. Good levels of internal consistency were found, with a KR-20 of 0.80 for the 18-item version, and 0.77 for the 14-item. The scale differentiates between population with 'high exposure to conflict' from population with 'low exposure' (dnp > 0.5 and area under the ROC >0.90). The scale scores have significant correlation with some mental health constructs. The EX2 scale has good internal consistency, as well as structural validity with regard to exposed groups. This scale can be potentially validated for its use in countries with armed confrontation history. In future versions, the scale may include additional items in order to improve content validity.

RNASEH1 gene variants are associated with autoimmune type 1 diabetes in Colombia.

BACKGROUND: In a previous work, we found linkage and association of type 1 diabetes (T1D) to a 12 known gene region at chromosome 2p25 in Colombian families. Here, we present further work on this candidate region. MATERIALS AND METHODS: Seventeen SNPs located on the 12 candidate genes, in 100 familial trios set, were tested by ARMS-tetraprimer-PCR or PCR-RFLP. Five extra SNPs in the vicinity of rs10186193 were typed. A replica phase included 97 novel familial trios, in whom diabetes-related auto-antibodies (AABs) were tested in sera of the patients. In addition to transmission disequilibrium tests, haplotype analyses were carried out using the unphased software. RESULTS: SNP rs10186193 (at RNASEH1 gene) showed association with T1D (P = 0.005). The additional five SNPs revealed that rs7607888 (P = 2.03 × 10-7), rs55981318 (P = 0.018), and rs1136545 (P = 1.93 × 10-9) were also associated with T1D. Haplotype analysis showed association for rs55981318-rs10186193 (P = 0.0005), rs7563960-rs7607888 (P = 0.0007), rs7607888-rs1136545 (P = 9.21 × 10-10), and rs1136545-rs11538545 (P = 6.67 × 10-8). In contrast, the new set of 97 familial trios tested for SNPs rs55981318, rs10186193, and rs7607888 did not support the previous finding; however, by combining the sample (197 trios), evidence of association of T1D with rs55981318 and rs7607888 was conclusive. In addition, a two-loci haplotype analysis of the combined sample showed significant association of RNASEH1 with T1D (P = 3.1 × 10-5). CONCLUSION: In conclusion, our analyses suggest that RNASEH1 gene variants associate with susceptibility/protection to T1D in Colombia.

Agenesia dental: Epidemiología, clínica y genética en pacientes antioqueños / Tooth agenesis: Epidemiological, clinical and genetic analysis in patients from Antioquia

Introducción: La odontogénesis es un proceso molecular complejo, susceptible a errores durante las etapas del desarrollo, que puede generar alteraciones, como agenesias dentales. Metodología: Se realizó una descripción epidemiológica de la agenesia dental en 814 pacientes de la Facultad de Odontología de la Universidad de Antioquía entre 2006 y 2008, con base en la historia clínica y radiografías panorámicas. Se evaluó clínica y genéticamente una familia con agenesia dental no sindrómica, se determinó el tipo de segregación y patrón de herencia con el fin de identificar la implicación de los genes MSX1 y PAX9 en la agenesia. Se realizó la Reacción de Polimerización en Cadena (PCR), genotipificación y análisis de ligamiento. Se seleccionaron los marcadores D4S2285 y D4S432 (MSX1) y D14S288 y D14S70 (PAX9) por su alto índice de heterocigocidad. Resultados: El análisis epidemiológico reveló mayor prevalencia de agenesias en la dentición permanente, en el sexo femenino, y los dientes más afectados fueron los tercero molares seguidos de los incisivos laterales superiores. Los resultados genéticos indicaron un posible ligamiento entre el gen MSX1 (LOD 0,97) con la agenesia dental y a su vez se identificó una posible asociación al azar del gen PAX9 (LOD -0,28) en la familia estudiada (AU)

Introduction: Odontogenesis is a complex molecular process, open to failures during different stages of development, that may lead to alterations like tooth agenesis. Methods: An epidemiological description was made about tooth agenesis in 814 patients in the Faculty of Dentistry of the Antioquia University between 2006 and 2008, using clinical histories and panoramic X-rays, Furthermore, a family with non-syndromic tooth agenesis, was evaluated clinically and genetically to determine the segregation type and the inheritance pattern, and to identify the possible implication of the MSX1 and PAX9 genes. The analysis of those genes was valuated through Polymerase Chain Reaction (PCR), genotyping and linkage analysis. The markers D4S2285 and D4S432 for MSX1 and D14S288 and D14S70 for PAX9, were selected by their high heterozigocity index. Results: The epidemiological analysis revealed a high prevalence of agenesis in permanent dentition and in the female gender, with predilection for third molars, followed by upper lateral incisors. The genetic findings showed a possible linkage between MSX1 gene (LOD 0.97) and the anomaly. At the same time a possible random association was found between the PAX9 gene (LOD -0.28) and the anomaly in the studied family (AU)

Contenido fenólico e identificación de levaduras de importancia vínica de la uva Isabella (Vitis labrusca) procedente de Villa del Rosario (Norte de Santander) / Phenolic potential determination and yeasts identification with significant leavens in Isabella grape (Vitis labrusca) from Villa del Rosario (Norte de Santander) for wine making

La uva Isabella (Vitis labrusca) es una variedad tinta que se ha adaptado óptimamente a las condiciones edafoclimáticas de la región de Villa del Rosario (Norte de Santander), y ha tenido buena aceptación en los mercados locales. Actualmente la uva se consume en fresco y se desconoce su contenido fenólico para la elaboración de vinos. El objetivo de este trabajo fue establecer el contenido fenólico e identificar las levaduras de importancia vínica de esta variedad. Para ello, se tomaron bayas de dos vendimias consecutivas. Se analizaron parámetros como densidad, sólidos solubles, pH, acidez y el contenido fenólico total y extraíble. Asimismo, se identificaron las levaduras morfológica y bioquímicamente. Los resultados de los parámetros fisicoquímicos de las dos vendimias se promediaron y compararon con las uvas procedentes del Valle del Cauca. Se concluyó que las bayas de las dos regiones fueron similares en sus características físicas, y diferentes significativamente en cuanto a su composición química. El contenido fenólico total fue mayor en las uvas del Valle del Cauca, mientras que el extraíble fue similar en las dos regiones. El examen microbiológico identificó cinco especies de levaduras: Kloeckera apiculata, Criptococcus laurentii, Candida guillermondii Candida novergensis y Rhodotorula glutinis.

The Isabella grape (Vitis labrusca) is a red variety that has been optimally adapted to the edafoclimaticconditions in the region of Villa del Rosario (Norte de Santander) and has been accepted also in local markets. Currently, the grape is eaten fresh and its potential for winemaking is unknown. Therefore, the purpose of this study was to establish the phenolic potential and identify important yeasts of this kind ofgrape for winemaking. To this end, berries taken from two consecutive vintages were analyzed. Parametersanalyzed were density, soluble solids, pH, acidity and total and removable phenolic potential. The yeasts were identified morphologically and biochemically. The results of the physicochemical parameters of the two vintages were averaged and compared with results for grapes from Valle del Cauca. The results indicated that the berries of the two regions were similar in physical characteristics but significantlydifferent in terms of chemical composition. The total phenolic potential was higher in grapes from Valle del Cauca, while removable was similar in the two regions. Five yeast species: Kloeckera apiculata, Criptococcus laurentii, Candida guillermondii, Candida novergensis and Rhodotorula glutinis were microbiologically isolated and identified.

Estudio Comparativo del Contenido Fenólico de Vinos Tintos Colombianos e Importados / Phenolic Comparison Between Colombian Red Wines and those imported

Los compuestos fenólicos tienen un papel muy importante en la calidad de los vinos tintos. Ellos proporcionan características sensoriales como sabor, aroma, color, astringencia, entre otras. En el presente estudio se analizan siete vinos tintos comerciales de diferente origen geográfico, a los cuales se les determina el índice de polifenoles totales (IPT), cantidad de taninos, cantidad de antocianos y las características cromáticas. En el análisis del IPT se observa que entre todos los vinos es similar sin importar el origen. Los vinos Colombianos presentan valores bajos de contenido de taninos y de antocianos que los vinos internacionales. Mientras que las características cromáticas en todos los vinos presentan un valor medio de intensidad colorante, siendo los vinos Colombianos los que menor valor presentan. En cuanto a la tonalidad los vinos Colombianos son similares a los vinos internacionales. De acuerdo a los resultados obtenidos se puede concluir que el IPT en todos los vinos es similar y que se encuentran en el rango normal de un vino tinto joven. Igualmente sucede lo mismo con las características cromáticas. Mientras que el contenido de antocianos de taninos en los vino Colombianos son más bajos que en los importados

Feature-selective attention enhances color signals in early visual areas of the human brain.

We used an electrophysiological measure of selective stimulus processing (the steady-state visual evoked potential, SSVEP) to investigate feature-specific attention to color cues. Subjects viewed a display consisting of spatially intermingled red and blue dots that continually shifted their positions at random. The red and blue dots flickered at different frequencies and thereby elicited distinguishable SSVEP signals in the visual cortex. Paying attention selectively to either the red or blue dot population produced an enhanced amplitude of its frequency-tagged SSVEP, which was localized by source modeling to early levels of the visual cortex. A control experiment showed that this selection was based on color rather than flicker frequency cues. This signal amplification of attended color items provides an empirical basis for the rapid identification of feature conjunctions during visual search, as proposed by "guided search" models.

A novel SCN1A mutation associated with severe GEFS+ in a large South American pedigree.

Generalized epilepsy with febrile seizures plus (GEFS+) is an inherited epileptic syndrome with a marked clinical and genetic heterogeneity. Here we report the molecular characterization of a large pedigree with a severe clinical form of GEFS+. Genetic linkage analysis implied the involvement of the FEB3 in the disease phenotype of this family (parametric two-point lod-score of 2.2). Sequencing of the SCN1A gene revealed a novel aspartic acid for glycine substitution at position 1742 of this sodium channel subunit. The amino-acid replacement lies in the pore-forming region of domain IV of SCN1A. Our observations are consistent with the genotype-phenotype correlation studies suggesting that mutations in the pore-forming loop of SCN1A can lead to a clinically more severe epileptic syndrome.

A CLN5 mutation causing an atypical neuronal ceroid lipofuscinosis of juvenile onset.

Three related patients from Colombia presented with a juvenile-onset neuronal ceroid lipofuscinosis. Electron microscopy of one case showed condensed fingerprint profiles, and genetic analyses identified a novel missense mutation in CLN5. The authors demonstrate the existence of pathogenic CLN5 mutations outside northern Europe and that mutations in this gene can lead to an atypical late-onset neuronal ceroid lipofuscinosis disease, in addition to the late infantile form first described in Finland.

Mutations in FOXL2 underlying BPES (types 1 and 2) in Colombian families.

We report the genetic characterization of one family with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) type 1 and two families with BPES type 2 from a historically isolated population in northwest Colombia. Linkage and haplotype analyses indicate that BPES in these families is linked to 3q23. Mutation screening of FOXL2 in the family with BPES type 1 revealed a novel 394C --> T nonsense mutation which deletes the forkhead DNA binding domain. The two families with BPES type 2 both carry an in-frame 30 bp duplication that leads to the elongation of a polyalanine tract. This duplication has been previously reported in Europe, where recurrent mutation has been demonstrated in unrelated familial and sporadic BPES cases. The recurrent nature of this duplication seems to relate to the secondary structure of this DNA region. The genotype-phenotype correlation seen in the Colombian families is consistent with the recent proposal that BPES type 1 is caused by truncating mutations leading to haploinsufficiency, while BPES type 2 is due to mutations generating elongated protein products.

Embarazo ectópico bilateral simultáneo / Simultaneous bilateral ectopic pregnancy

Se presenta el caso clínico de una paciente de 29 años de edad, la cual fue sometida a una laparotomía exploradora, con el diagnósticos de embarazo tubario derecho complicado. En el acto operatorio se comprueba dicho diagnóstico, agregándose como hallazgo, la presencia de un embarazo tubario izquierdo.

We present a clinical case of a 29 year-old patient, which was subjected to an exploratory laparotomy with the diagnosis of a complicated right tubal pregnancy. At operation is proven this diagnosis, and the presence of a left tubal pregnancy was found.

A novel Cys212Tyr founder mutation in parkin and allelic heterogeneity of juvenile Parkinsonism in a population from North West Colombia.

We report the molecular characterization of three multiplex families and a sporadic case of juvenile Parkinsonism identified in the province of Antioquia (Colombia). Linkage and haplotype analysis using markers in 6q25.2-27 indicated that Parkinsonism in the pedigrees is linked to the parkin gene (maximum LOD-score of 3.85) but that they carry two different mutant haplotypes. Sequence analysis revealed a novel G to A transition in exon 6 at position 736 (G736A) of parkin. This change results in a non-conservative cysteine for tyrosine substitution. All affected individuals from two families were homozygous for this mutation, which was not detected in 100 normal controls. Patients from the family carrying the second haplotype and the sporadic case were homozygous for a GT insertion in exon 3. This mutation has been previously identified in French families with juvenile Parkinsonism. The concomitant presence of founder effects and allelic heterogeneity in Antioquia might relate to the founding admixture at the origin of this population.

Sarcoma uterino: dificultad diagnóstica preoperatoria / Uterine sarcoma: preoperative diagnostic difficulty

Se presenta 4 casos de Sarcoma Uterino ocurridos en el Hospital Félix Bulnes Cerda entre los años 1999 y 2000. Todos los casos fueron diagnosticados por el estudio histopatológicos postoperatorio. Se destaca la dificultad diagnóstica preoperatoria, pudiendo no ser posible en la mayoría de las pacientes. Este factor es el responsable, en parte, de su desfavorable pronóstico

Intracerebral sources of human auditory-evoked potentials.

Evoked potentials to brief 1,000-Hz tones presented to either the left or the right ear were recorded from 30 electrodes arrayed over the head. These recordings were submitted to two different forms of source analysis: brain electric source analysis (BESA) and variable-resolution electromagnetic tomography (VARETA). Both analyses showed that the dominant intracerebral sources for the late auditory-evoked potentials (50-300 ms) were in the supratemporal plane and lateral temporal lobe contralateral to the ear of stimulation. The analyses also suggested the possibility of additional sources in the frontal lobes.

Utility of three-dimensional ultrasound Doppler flow reconstruction of the proximal jet to quantify effective orifice area: in vitro steady and pulsatile flow studies.

We examined the utility of three-dimensional (3D) reconstruction of two-dimensional color Doppler images of the proximal jet to quantify the effective area of an orifice in an in vitro model. Steady and pulsatile flows were directed through various orifices; orifice vena contracta areas were quantified with laser flow visualization, thus providing gold standard effective orifice areas. Three-dimensional areas followed vena contracta areas well, although variations in color Doppler gain and 3D gray levels for thresholding produced significant changes in reconstructed images. These variations were minimized by using minimum color gain and 50% gray level threshold. At these settings, 3D areas still overestimated vena contracta areas by approximately 25% because of the poor lateral resolution of the color Doppler system, which caused bleeding of the flow signal past the edges of the proximal jet. Nevertheless, 3D flow images provided a superior format for qualitative and quantitative appreciation of proximal jet shape and dimensions.

Alveolar-arterial oxygen gradient in acute pulmonary embolism in pregnancy.

OBJECTIVE: Our goal was to determine the prevalence of normal alveolar-arterial gradients in pregnant patients with documented pulmonary embolism. STUDY DESIGN: A retrospective chart review was performed on all pregnant women with pulmonary embolism at two large obstetric centers between 1990 and 1995. Alveolar-arterial gradients were calculated from room air arterial blood gas values and compared with values from patients who had been established as normal. RESULTS: Ten of 17 patients with pulmonary embolism identified had alveolar-arterial gradients that were normal. CONCLUSIONS: In our study 58% of pregnant women with documented pulmonary embolism had a normal alveolar-arterial gradient. This markedly differs from the published data in nonpregnant patients, in which the incidence of normal alveolar-arterial gradients in pulmonary embolism has ranged from 1.9% to 20%. This suggests that the alveolar-arterial gradient should not be used to determine the likelihood of pulmonary embolism in pregnant women because this could lead to the withholding of appropriate treatment for this life-threatening condition.

DTPA aerosol in ventilation/perfusion scintigraphy for diagnosing pulmonary embolism.

UNLABELLED: The use of lung scintigraphy in evaluating suspected pulmonary embolism (PE) is controversial. Several diagnostic methods have been described for lung scans, of which the most widely applied uses 99mTc-MAA for perfusion, 133Xe for ventilation and PIOPED diagnostic criteria. This study evaluates the accuracy of lung scintigraphy using an alternative ventilation agent, 99mTc-diethylenetriamine pentacetic acid (DTPA) aerosol, and specific criteria. METHODS: Diagnostic criteria for DTPA aerosol ventilation were prospectively applied to 5017 patients over a 9-yr period. Lung scan interpretations were analyzed for frequency of occurrence, and results were compared to those of angiography in 455 patients. RESULTS: Scans were interpreted as normal, low or high probability in 79% of patients and as either indeterminate or medium probability in 21% of patients. Three patients had normal scans and negative angiography. In patients with low-probability scans, 111 angiograms were performed: 103 (93%) were negative, and 8 (7%) were positive. In patients with indeterminate scans, 114 angiograms were performed: 85 (75%) were negative, and 29 (25%) were positive. In patients with medium-probability scans, 149 angiograms were performed: 86 (58%) were negative, and 63 (42%) were positive. In patients with high-probability scans, 78 angiograms were performed: 6 (8%) were negative, and 72 (92%) were positive. CONCLUSION: These results indicate that lung scintigraphy using DTPA aerosol and our criteria is accurate in diagnosing and stratifying risk of pulmonary embolic disease. Compared with 133Xe and PIOPED criteria, DTPA ventilation and our criteria reduced the false-negative rate in low-probability scans (7% versus 16%, p < 0.005) and decreased the fraction of intermediate-probability scans (21 % versus 39%, p < 0.01).

Current concepts in aortic stenosis.

Noninvasive cardiac imaging techniques now make it possible to determine the morphologic and hemodynamic status of patients with aortic stenosis, even in early asymptomatic stages of the disease. This is particularly important since the prognosis is generally poor once symptoms are apparent and since replacement of the aortic valve is usually the only recourse when stenosis is severe.