Fear of heights: cognitive performance and postural control

Fear of heights, or acrophobia, is one of the most frequent subtypes of specific phobia frequently associated to depression and other anxiety disorders. Previous evidence suggests a correlation between acrophobia and abnormalities in balance control, particularly involving the use of visual information to keep postural stability. This study investigates the hypotheses that (1) abnormalities in balance control are more frequent in individuals with acrophobia even when not exposed to heights, that (2) acrophobic symptoms are associated to abnormalities in visual perception of movement; and that (3) individuals with acrophobia are more sensitive to balance-cognition interactions. Thirty-one individuals with specific phobia of heights and thirty one non-phobic controls were compared using dynamic posturography and a manual tracking task. Acrophobics had poorer performance in both tasks, especially when carried out simultaneously. Previously described interference between posture control and cognitive activity seems to play a major role in these individuals. The presence of physiologic abnormalities is compatible with the hypothesis of a non-associative acquisition of fear of heights, i.e., not associated to previous traumatic events or other learning experiences. Clinically, this preliminary study corroborates the hypothesis that vestibular physical therapy can be particularly useful in treating individuals with fear of heights.

The effects of bromazepam over the temporo-parietal areas during the performance of a visuomotor task: A qEEG study

This study investigated the effects of bromazepam on qEEG when 14 healthy subjects were asked to perform a visuomotor task (i.e., motor vehicle driving task). The subjects were exposed to two experimental conditions: the placebo (PL) and 6 mg of bromazepam (Br 6 mg), following a randomized, double-blind design on different days. Specifically, we observe absolute power extracted from qEEG data for theta band. We expected to see a decrease in absolute theta power in the temporal and parietal areas due to the influence of bromazepam for the experimental group when compared with the placebo group. We found a main effect for the condition factor for electrodes T3, T4, P3 and P4. We also observed a main effect for the period factor for electrodes P3 and P4. We observed that the ingestion of 6 mg of bromazepam induces different patterns in theta power at the temporal and parietal sites. We concluded that 6 mg of bromazepam was an important factor in the fluctuation of the activities in the temporal and parietal areas. We then hypothesize about the specific role of this drug during the execution of a visuomotor task and within the sensorimotor integration process. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

Performance of patients with refractory obsessive-compulsive disorder in the Frontal Systems Behavior Scale

Objective: To compare the performance of patients with obsessive-compulsive disorder (OCD) refractory to conventional treatments to healthy controls according to the Frontal Systems Behaviour Scale (FrSBe), comparing the scale scores within each group (Self or Family) and correlating FrSBe with Y-BOCS, DY-BOCS, tic disorder and age of first symptoms. Method: Twenty OCD patients and 20 healthy controls were assessed using the FrSBe, a scale designed to evaluate frontal syndromes. Results: The patients had higher scores when compared with the control group (p value .001) in terms of total score on the scale for both profile forms (Self and Family). In addition, there was a significant difference between the scores reported by the patients and their respective relatives. However, no correlation was observed between the scale and the other variables. Conclusions: The scale was able to clearly differentiate patients with OCD from healthy controls. This finding suggests that the FrSBe can be used not only in neurologic patients but also in psychiatric cases such as refractory OCD.

Integration of Cortical Areas during Performance of a Catching Ball Task

The study aimed to elucidate electrophysiological and cortical mechanisms involved in anticipatory actions when healthy subjects had to catch balls in free drop. Specific alpha absolute power changes were measured in quantitative electroencephalography (qEEG). Our hypothesis is that during the preparation of motoraction (i.e.. 2 s before the ball drops) integration occurs among the left medial frontal, left primary somatomotor and left posterior parietal cortices, showing a differentiated activity involving expectation, planning and preparedness. We contend that in right-handers, the left hemisphere takes on a dominant role for the regulation of motor behavior. The sample was composed of 23 healthy right handed subjects (13 men and 10 women), with ages varying between 25 and 40 years old (32.5 +/- 7.5), absence of mental and physical illness. The experiment consisted of a task of catching balls with the right hard in free drop. The three-way ANOVA analysis demonstrated all interaction between moment and position in left-medial frontal cortex (F3 electrode), somatomotor cortex (C3 electrode) and posterior parietal cortex (P3 electrode: p < 0.05). Summarizing, the experimental task enabled the observation of integration among frontal, central and parietal regions. This integration appears to be more predominant in expectation, planning and motor preparation.

Executive dysfunction correlates with impaired functional status in older adults with varying degrees of cognitive impairment

Background: Previous studies have reported an association between executive dysfunction and the ability to perform activities of daily living (ADL)s among older adults. This study aims to examine the association between executive functions and functional status in a cross-section of older adults with varying degrees of cognitive impairment. Methods: 89 individuals (mean age 73.8 years) were recruited at a memory clinic in Sao Paulo, Brazil. Subjects underwent evaluation, and were allocated into three diagnostic groups according to cognitive status: normal controls (NC, n = 32), mild cognitive impairment (MCI, n = 3 1) and mild Alzheimer`s disease (AD, n=26). Executive functions were assessed with the 25-item Executive Interview (EXIT25), and functional status was measured with the Direct Assessment of Functional Status test (DAFS-R). Results: Significantly different total DAFS-R scores were observed across the three diagnostic groups. Patients with AD performed significantly worse in EXIT25 compared with subjects without dementia, and no significant differences were detected between NC and MCI patients. We found a robust negative correlation between the DAFS-R and the EXIT25 scores (r=-0.872, p < 0.001). Linear regression analyses suggested a significant influence of the EXIT-25 and the CAMCOG on the DAFS-R scores. Conclusion: Executive dysfunction and decline in general measures of cognitive functioning are associated with a lower ability to undertake instrumental ADLs. MCI patients showed worse functional status than NC subjects. MCI patients may show subtle changes in functional status that may only be captured by objective measures of ADLs.

Integration of cortical areas during performance of a catching ball task

The study aimed to elucidate electrophysiological and cortical mechanisms involved in anticipatory actions when healthy subjects had to catch balls in free drop; specifically through quantitative electroencephalography (qEEG) alpha absolute power changes. Our hypothesis is that during the preparation of motor action (i.e., 2 s before ball`s drop) occurred integration among left medial frontal, left primary somatomotor and left posterior parietal cortices, showing a differentiated activity involving expectation, planning and preparedness. This hypothesis supports a lateralization of motor function. Although we contend that in right-handers the left hemisphere takes on a dominant role for the regulation of motor behavior. The sample was composed of 23 healthy subjects (13 male and 10 female), right handed, with ages varying between 25 and 40 years old (32.5 +/- 7.5), absence of mental and physical illness, right handed, and do not make use of any psychoactive or psychotropic substance at the time of the study. The experiment consisted of a task of catching balls in free drop. The three-way ANOVA analysis demonstrated an interaction between moment and position in left medial frontal cortex (F3 electrode), somatomotor cortex (C3 electrode) and posterior parietal cortex (P3 electrode: p < 0.001). Summarizing, through experimental task employed, it was possible to observe integration among frontal, central and parietal regions. This integration appears to be more predominant in expectation, planning and motor preparation. In this way, it established an absolute predominance of this mechanism under the left hemisphere. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Trigger performance of mid-level ICU mechanical ventilators during assisted ventilation: a bench study

Objective: To compare the triggering performance of mid-level ICU mechanical ventilators with a standard ICU mechanical ventilator. Design: Experimental bench study. Setting: The respiratory care laboratory of a university-affiliated teaching hospital. Subject: A computerized mechanical lung model, the IngMar ASL5000. Interventions: Ten mid-level ICU ventilators were compared to an ICU ventilator at two levels of lung model effort, three combinations of respiratory mechanics (normal, COPD and ARDS) and two modes of ventilation, volume and pressure assist/control. A total of 12 conditions were compared. Measurements and main results: Performance varied widely among ventilators. Mean inspiratory trigger time was < 100 ms for only half of the tested ventilators. The mean inspiratory delay time (time from initiation of the breath to return of airway pressure to baseline) was longer than that for the ICU ventilator for all tested ventilators except one. The pressure drop during triggering (Ptrig) was comparable with that of the ICU ventilator for only two ventilators. Expiratory Settling Time (time for pressure to return to baseline) had the greatest variability among ventilators. Conclusions: Triggering differences among these mid-level ICU ventilators and with the ICU ventilator were identified. Some of these ventilators had a much poorer triggering response with high inspiratory effort than the ICU ventilator. These ventilators do not perform as well as ICU ventilators in patients with high ventilatory demand.

Comparison of HRT-3 glaucoma probability score and subjective stereophotograph assessment for prediction of progression in glaucoma

PURPOSE. To assess whether baseline Glaucoma Probability Score (GPS; HRT-3; Heidelberg Engineering, Dossenheim, Germany) results are predictive of progression in patients with suspected glaucoma. The GPS is a new feature of the confocal scanning laser ophthalmoscope that generates an operator-independent, three-dimensional model of the optic nerve head and gives a score for the probability that this model is consistent with glaucomatous damage. METHODS. The study included 223 patients with suspected glaucoma during an average follow-up of 63.3 months. Included subjects had a suspect optic disc appearance and/or elevated intraocular pressure, but normal visual fields. Conversion was defined as development of either repeatable abnormal visual fields or glaucomatous deterioration in the appearance of the optic disc during the study period. The association between baseline GPS and conversion was investigated by Cox regression models. RESULTS. Fifty-four (24.2%) eyes converted. In multivariate models, both higher values of GPS global and subjective stereophotograph assessment ( larger cup-disc ratio and glaucomatous grading) were predictive of conversion: adjusted hazard ratios (95% CI): 1.31 (1.15 - 1.50) per 0.1 higher global GPS, 1.34 (1.12 - 1.62) per 0.1 higher CDR, and 2.34 (1.22 - 4.47) for abnormal grading, respectively. No significant differences ( P > 0.05 for all comparisons) were found between the c-index values ( equivalent to area under ROC curve) for the multivariate models (0.732, 0.705, and 0.699, respectively). CONCLUSIONS. GPS values were predictive of conversion in our population of patients with suspected glaucoma. Further, they performed as well as subjective assessment of the optic disc. These results suggest that GPS could potentially replace stereophotograph as a tool for estimating the likelihood of conversion to glaucoma.

A decision support system to facilitate management of patients with acute gastrointestinal bleeding

Objective: To develop a model to predict the bleeding source and identify the cohort amongst patients with acute gastrointestinal bleeding (GIB) who require urgent intervention, including endoscopy. Patients with acute GIB, an unpredictable event, are most commonly evaluated and managed by non-gastroenterologists. Rapid and consistently reliable risk stratification of patients with acute GIB for urgent endoscopy may potentially improve outcomes amongst such patients by targeting scarce health-care resources to those who need it the most. Design and methods: Using ICD-9 codes for acute GIB, 189 patients with acute GIB and all. available data variables required to develop and test models were identified from a hospital medical records database. Data on 122 patients was utilized for development of the model and on 67 patients utilized to perform comparative analysis of the models. Clinical data such as presenting signs and symptoms, demographic data, presence of co-morbidities, laboratory data and corresponding endoscopic diagnosis and outcomes were collected. Clinical data and endoscopic diagnosis collected for each patient was utilized to retrospectively ascertain optimal management for each patient. Clinical presentations and corresponding treatment was utilized as training examples. Eight mathematical models including artificial neural network (ANN), support vector machine (SVM), k-nearest neighbor, linear discriminant analysis (LDA), shrunken centroid (SC), random forest (RF), logistic regression, and boosting were trained and tested. The performance of these models was compared using standard statistical analysis and ROC curves. Results: Overall the random forest model best predicted the source, need for resuscitation, and disposition with accuracies of approximately 80% or higher (accuracy for endoscopy was greater than 75%). The area under ROC curve for RF was greater than 0.85, indicating excellent performance by the random forest model Conclusion: While most mathematical models are effective as a decision support system for evaluation and management of patients with acute GIB, in our testing, the RF model consistently demonstrated the best performance. Amongst patients presenting with acute GIB, mathematical models may facilitate the identification of the source of GIB, need for intervention and allow optimization of care and healthcare resource allocation; these however require further validation. (c) 2007 Elsevier B.V. All rights reserved.

PREDICTION OF FAT-FREE MASS BY BIOELECTRICAL IMPEDANCE ANALYSIS IN OLDER ADULTS FROM DEVELOPING COUNTRIES: A CROSS-VALIDATION STUDY USING THE DEUTERIUM DILUTION METHOD

Objective: Several limitations of published bioelectrical impedance analysis (BIA) equations have been reported. The aims were to develop in a multiethnic, elderly population a new prediction equation and cross-validate it along with some published BIA equations for estimating fat-free mass using deuterium oxide dilution as the reference method. Design and setting: Cross-sectional study of elderly from five developing countries. Methods: Total body water (TBW) measured by deuterium dilution was used to determine fat-free mass (FFM) in 383 subjects. Anthropometric and BIA variables were also measured. Only 377 subjects were included for the analysis, randomly divided into development and cross-validation groups after stratified by gender. Stepwise model selection was used to generate the model and Bland Altman analysis was used to test agreement. Results: FFM = 2.95 - 3.89 (Gender) + 0.514 (Ht(2)/Z) + 0.090 (Waist) + 0.156 (Body weight). The model fit parameters were an R(2), total F-Ratio, and the SEE of 0.88, 314.3, and 3.3, respectively. None of the published BIA equations met the criteria for agreement. The new BIA equation underestimated FFM by just 0.3 kg in the cross-validation sample. The mean of the difference between FFM by TBW and the new BIA equation were not significantly different; 95% of the differences were between the limits of agreement of -6.3 to 6.9 kg of FFM. There was no significant association between the mean of the differences and their averages (r = 0.008 and p = 0.2). Conclusions: This new BIA equation offers a valid option compared with some of the current published BIA equations to estimate FFM in elderly subjects from five developing countries.

Influence of treadmill training on motor performance and organization of exploratory behavior in Meriones unguiculatus with unilateral ischemic stroke: Histological correlates in hippocampal CA1 region and the neostriatum

This study examined the effects of motor stimulation via treadmill on the behavior of male gerbils after external carotid ischemic brain lesion. The animals were assigned to five groups; ischemic with no stimulation (SIG), ischemic with stimulation (SIG 12/24/48/72 It after surgery), non-ischemic with no stimulation (CC), non-ischemic with stimulation (CE) and sham, surgery without occlusion with no stimulation (SH). All the animals were tested in the open-field (OF) and rotarod (RR), 4 days after surgery in order to evaluate exploratory behaviors and motor performance. Data were submitted to one-way variance (ANOVA) and Dunnett`s post hoc comparisons. SIG and SIG 12 groups showed a significant decrease in motor response (crossing) when compared to the control group (CC) (F = 20.65, P < 0.05) in the OF. SIG 12 group showed an increase in grooming behavior (F = 23.136, P < 0.05) and all ischemia groups (SIG, SIG 12/24/48/72) spent less time on the RR (F = 10.40, P < 0.05), when compared to the control group (CC). Histological analyses show extensive lesions in the hippocampus and neostriatum for all groups with ischemia (SIG, SIG 12/24/48/72), which are structures involved in the organization of motor behavior. Interestingly, the most pronounced damage was found in animals submitted to motor stimulation 12 h after ischemia which can be correlated to the increased number of grooming behavior showed by them in the OF. These findings suggest that motor stimulation through treadmill training improve motor behavior after ischemia, except when it starts 12h after surgery. (c) 2007 Elsevier Ireland Ltd. All rights reserved.

From medical librarian to informacionist: semantic traces of their profiles and areas of performance

This literature review retakes the discussion of the profiles and competences of the information area professional, specifically, in the health field. Therefore, the aim here is to outline the new fields of performance for the informationist and the profiles required in the health context.

Performance of a chromogenic medium for the isolation of Listeria monocytogenes in food

According to the producers, CHROMagar (TM) Listeria medium comes to facilitate the detection, differentiating Listeria monocytogenes from the other species, directly on the isolation process, allowing final results in 72 h, while the traditional method takes up to 10 days. A total of 120 food samples of sliced cooked ham, ground beef and frankfurters was analyzed. From 151 colonies presenting typical L. monocytogenes characteristics on CHROMagar (TM) Listeria (bluish, surrounded by a white halo), only 95 (62.9%) were confirmed as L. monocytogenes. The medium was highly sensitive to detect L. monocytogenes in ground beef and frankfurter, but not in sliced ham. (c) 2007 Elsevier Ltd. All rights reserved.

Evaluation of the performance of normal elderly in a limb praxis protocol: Influence of age, gender, and education

Limb praxis can be influenced by age, gender, and education. The present Study investigated the influence of these variables on gesture production by healthy elderly Subjects. We evaluated 96 individuals divided into two age groups (60-74 and 75-88 years). Each group contained 48 men and 48 women and was subdivided into four groups according to education: illiterates and 1-3, 4-7, and 8 or more years of education. Individuals were requested to carry Out tasks oil verbal command and imitation. There were no differences between the performance of men and women, while older individuals performed worse than their younger counterparts. Regarding educational level, three major groups emerged: illiterates, individuals with 1-7 years of education, and those with 8 or more years of education. In conclusion, age and education significantly influenced the performance of individuals in limb praxis tests. (JINS, 2009, 157 618-622.)

Development and agronomic performance of common bean lines simultaneously resistant to anthracnose, angular leaf spot and rust

The common bean is affected by several pathogens that can cause severe yield losses. Here we report the introgression of resistance genes to anthracnose, angular leaf spot and rust in the `carioca-type` bean cultivar `Ruda`. Initially, four backcross (BC) lines were obtained using `TO`, `AB 136`, `Ouro Negro` and `AND 277` as donor parents. Molecular fingerprinting was used to select the lines genetically closer to the recurrent parent. The relative genetic distances between `Ruda` and the BC lines varied between 0.0% and 1.99%. The BC lines were intercrossed and molecular markers linked to the resistance genes were used to identify the plants containing the genes of interest. These plants were selfed to obtain the F(2), F(3) and F(4) plants which were selected based on the presence of the molecular markers mentioned and resistance was confirmed in the F(4) generation by inoculation. Four F(4:7) pyramid lines with all the resistance genes showed resistance spectra equivalent to those of their respective donor parents. Yield tests showed that these lines are as productive as the best `carioca-type` cultivars.