Poststroke consequences upon optimization properties of postural sway during upright stance: a cross-sectional study

BACKGROUND

The understanding of human postural control has advanced with the introduction of optimization process modeling. These models, however, only provide control parameters, rather than analytical descriptors of optimization processes. Here, we use a newly developed direct (pattern) search algorithm to investigate changes in postural optimization process in poststroke individuals.

OBJECTIVE

This cross-sectional study investigated the optimization properties of postural stability during upright standing in poststroke individuals.

METHODS

Twenty-nine poststroke and 15 healthy age-matched individuals underwent posturography with a force platform while standing for 60 s for acquisition of center-of-pressure data. Poststroke individuals were grouped depending on their weight-bearing (WB) pattern and their balance capability assessed through Berg Balance Scale (BBS). The optimization properties of postural stability were computed assuming the minimization of postural sway as cost function.

RESULTS

The asymmetric WB poststroke group showed larger convergence rate toward the local minimum of postural sway than the symmetric WB group. Additionally, the low-balance capability group exhibited smaller values for averaged local minima and global minimum of postural sway coordinates compared with high-balance capability group. Significant correlations were found for BBS and the local minima and global minimum (Pearson's r ranged 0.378-0.424, P < 0.05).

CONCLUSIONS

In summary, the optimization properties describing postural dynamic stability, steadiness, and global reference are altered in poststroke individuals with asymmetric WB pattern and low-balance capability.

Short-Term Changes in Posture and Pain of the Neck and Lower Back of Women Undergoing Lipoabdominoplasty: A Case Series Report

Objective

The purpose of this study was to analyze short-term variations in posture and intensity of neck and lower back pain in women undergoing lipoabdominoplasty.

Methods

This prospective case series study involved 17 women (age 43 ± 12 years, presurgical body mass index 27.0 ± 3.7 kg/m2). Participants were assessed preoperatively (T0) and at 15 (T15) and 30 days (T30) after surgery for clinical data (number of pregnancies, number of deliveries, presurgical body mass), neck and lower back angles calculated by photogrammetry, and pain intensity by numeric pain rating scale. Postoperative complications were assessed at T15 and T30.

Results

After adjusting for age and presurgical body mass index, there was an increase in forward head position in T15 and a return by T30 (marginal R2 = 0.411). The lower back showed an increase in flexion at T15 and return by T30 (marginal R2 = 0.266). No statistical evidence of significance was observed for changes in the intensity of neck (P > .355) or lower back (P > .293) pain. Complications were mild and common at T15; most of them resumed at T30.

Conclusion

A transient, nonlinear compensatory change in neck and lower back lordosis was observed 15 days after lipoabdominoplasty, with almost full recovery in the short term (30 days). No systematic change in pain intensity was observed within this period. Postsurgical complications were mild and common, and most of them resumed shortly after surgery.

The use of Artificial Intelligence in predicting Respiratory Syncytial Virus-inhibiting flavonoids

Human Respiratory Syncytial Virus (hRSV) infection results in death and hospitalization of thousands of people worldwide each year. Unfortunately, there are no vaccines or specific treatments for hRSV infections. Screening hundreds or even thousands of promising molecules is a challenge for science. We integrated biological, structural, and physicochemical properties to train and to apply the concept of artificial intelligence (AI) able to predict flavonoids with potential anti-hRSV activity. During the training and simulation steps, the AI produced results with hit rates of more than 83%. The better AIs were able to predict active or inactive flavonoids against hRSV. In the future, in vitro and/or in vivo evaluations of these flavonoids may accelerate trials for new anti-RSV drugs, reduce hospitalizations, deaths, and morbidity caused by this infection worldwide, and be used as input in these networks to determine which parameter is more important for their decision.

Posturography measures in specific ballet stance position discriminate ballet dancers with different occurrences of musculoskeletal injuries

BACKGROUND

This study aimed to identify the postural sway variables that can distinguish between ballet dancers with high and low occurrences of musculoskeletal injuries.

METHODS

Fourteen professional ballet dancers were assigned to a high-occurrence group (N = 5, reports >2 injuries in the previous 6-months) or a low-occurrence group (N = 9, reports ≤1 injury). Center-of-pressure (COP) data were acquired using a force platform during the following tasks: single-leg stance with eyes open, single-leg stance with eyes closed, and demi-pointe stance with eyes open. The COP standard deviation (SD) and range (RA) in both the medial-lateral (ML) and anterior-posterior (AP) directions were estimated. Between-group comparisons were made through Welch's t-tests for unequal sample size along the effect size measure (Cohen's d). Spearman's rho was used to estimate the association between the number of injuries and the COP variables. The statistical threshold was set at 1%.

RESULTS

A between-group effect was found only for the demi-pointe stance, with large effects for SDML (P = 0.006, d = 1.7), RAAP (P = 0.006, d = 1.7), and RAML (P = 0.005, d = 1.7). An inverse relationship was found between the number of injuries and the demi-pointe's COP range in both directions (Spearman's rho from -0.681 to -0.726, P = 0.007).

CONCLUSIONS

COP measures taken in ballet-specific positions can distinguish between dancers with a high and low occurrence of musculoskeletal injuries. Suggestions are made to include ballet-specific tasks in the functional assessments of professional dancers.

Is postexercise hypotension a method-dependent phenomenon in chronic stroke? A crossover randomized controlled trial

BACKGROUND

This study assessed the reproducibility of postexercise hypotension (PEH) detection after two bouts of mixed circuit training (MCT) using three approaches that accounts the pre-exercise values and/or a control session (CTL) to calculate PEH [i.e., ( A 1 = post - exercise - pre - exercise ${A}_{1}=\text{post}{\rm{ \mbox{-} }}\text{exercise}-\text{pre}{\rm{ \mbox{-} }}\text{exercise}$ ); ( A 2 = post - exercise - post - CTL ) $({A}_{2}=\text{post}{\rm{ \mbox{-} }}\text{exercise}-\text{post}{\rm{ \mbox{-} }}\text{CTL})$ ; A 3 = ( post - exercise - pre - exercise ) - ( post - CTL - pre - CTL ) ] ${A}_{3}=(\text{post}{\rm{ \mbox{-} }}\text{exercise}-\text{pre}{\rm{ \mbox{-} }}\text{exercise})-(\text{post}{\rm{ \mbox{-} }}\text{CTL}-\text{pre}{\rm{ \mbox{-} }}\text{CTL})]$ in chronic stroke (i.e., ≥6 months poststroke). The proportion of PEH responders determined using different cut-off values for PEH was also compared (4 mmHg vs. minimal detectable difference).

METHODS

Seven participants (age: 56 ± 12 years; time post-stroke: 91 ± 55 months) performed two bouts of MCT and a CTL. The MCT involved 10 exercises with 3 sets of 15-repetition maximum, with each set interspersed with 45 s of walking. The systolic (SBP) and diastolic (DBP) blood pressures were assessed 10-min before and every 10-min along 40-min after CTL and MCT.

RESULTS

The two-way random intraclass correlation coefficient for single measurements (ICC_2,1 ) ranges for SBP were: A₁ : 0.580-0.829, A₂ : 0.937-0.994, A₃ : 0.278-0.774; for DBP: A₁ : 0.497-0.916, A₂ : 0.133-0.969, A₃ : 0.175-0.930. The proportion of PEH responders detected using 4 mmHg or the minimal detectable difference as cut-off values was not different in 97% of analyses (p > 0.05), and higher when using 4 mmHg in 3% of analyses (p = 0.031). The standard error of measurement was ≥4 mmHg in 47% of analyses for SBP, and 40% for DBP.

CONCLUSIONS

The most reliable approach for determining PEH in chronic stroke was to subtract the postexercise from the post-CTL values. The proportion of PEH responders was not affected by the cut-off values applied.

Accuracy of Palpation Procedures for Locating the C1 Transverse Process and Masseter Muscle as Confirmed by Computed Tomography Images

OBJECTIVE

The purpose of this study was to examine the accuracy of palpation methods for locating the transverse processes of the first cervical vertebra and masseter muscle using radiographic images as the gold-standard method and the association between personal characteristics with the observed accuracy.

METHODS

This was a single-blinded, diagnostic accuracy study. Ninety-five participants (49 women, 58 ± 16 years of age) were enrolled in this study. A single examiner palpated the neck and face region of all participants to identify the transverse processes of the first cervical vertebra and masseter muscles bilaterally. In sequence, participants underwent a multislice computed tomography scan for assessment of the superimposed inner body structure. Two radiologists assessed the computed tomography images using the same criteria and were blinded regarding each other's assessment and the anatomic landmarks under investigation. The palpation accuracy was calculated as the proportion of the correctly identified landmarks in the studied sample. The correlation of the palpation outcome (correct = 1; incorrect = 0) with age, sex (male = 1; female = 0), and body mass index was investigated using the point-biserial correlation coefficient.

RESULTS

The right and left transverse processes were correctly located in 76 (80%) and 81 (85%) participants, respectively, and bilaterally in 157 events (83%), as evaluated by the consensus of the 2 radiologists. The masseter muscles were correctly localized bilaterally in 95 of 95 (100%) participants. Body mass showed statistical evidence of a weak, positive correlation with the correct location of the transverse processes of the first cervical vertebra at the right body side (r = .219; 95% confidence interval, 0.018-0.403; P = .033).

CONCLUSION

Palpation methods used in this study accurately identified the location of the first cervical vertebra spinous processes and the masseter muscles.

Transcranial direct current stimulation combined with trunk-targeted, proprioceptive neuromuscular facilitation in subacute stroke: a randomized controlled trial

Background

Stroke is the foremost cause of death and disability worldwide. Improving upper extremity function and quality of life are two paramount therapeutic targets during rehabilitation.

Aim of the study

To investigate the effects of transcranial direct current stimulation (tDCS) combined with trunk-targeted proprioceptive neuromuscular facilitation (PNF) on impairments, activity limitations, and participation restrictions of subjects with subacute stroke.

Methodology

Fifty-four subjects with subacute stroke were divided into three groups using block randomization. All three groups received rehabilitation sessions lasting 90 min in duration, four times per week, for 6 weeks. Group 1 (n = 18) received conventional physical therapy (CPT); group 2 (n = 18) received CPT, trunk-targeted PNF, and sham tDCS; and group 3 (n = 18) received CPT, trunk-targeted PNF, and bihemispheric motor cortex stimulation with tDCS. Changes in motor impairment, motor activity, and health-related quality of life assessments were outcome measures.

Results

A two-way linear mixed model analysis revealed interaction effects (group × time) for all outcome measurements (Trunk Impairment Scale, Fugl-Meyer Assessment of Motor Recovery after stroke upper extremity subsection, Wolf Motor Function Test, 10-Meter Walk Test, and the Stroke-Specific Quality of Life scale; all p < 0.01 or lower). Overall, post-pre mean differences demonstrate more substantial improvement in the active tDCS group, followed by sham stimulation associated with the PNF group and the group that received CPT alone.

Conclusion

Trunk-targeted PNF combined with bihemispheric tDCS along with CPT engender larger improvements in upper extremity and trunk impairment, upper limb function, gait speed, and quality of life in the subacute stroke population.

Does group-based high-intensity aerobic interval training improve the inflammatory status in patients with chronic heart failure?

BACKGROUND

Chronic heart failure (CHF) is a multifaceted syndrome associated with endothelial dysfunction and increased inflammation. Despite the existing controversies regarding the appropriate training modality, it is widely accepted that supervised cardiac rehabilitation (CR) interventions lead to proinflammatory biomarkers reduction and cellular adhesion molecules in patients with CHF.

AIM

The aim of the study was to quantify the effects of 12-week group-based high-intensity aerobic interval training (HIAIT)/modified group-based HIAIT intervention (m-Ullevaal) vs. moderate continuous training (MICT) on serum levels of proinflammatory biomarkers.

DESIGN

Single-blind, two-arm, prospective randomized controlled trial conducted on CHF outpatients performing group-based CR interventions throughout a 12-week period.

SETTING

The setting of the study was the Medical Center of Outpatient Rehabilitation and Sports Medicine, Plovdiv, Bulgaria.

POPULATION

The population included a total of 120 outpatients of both genders, mean age of 63.73±6.68 years, with stable CHF (NYHA classes II to IIIB, were randomly assigned to HIAIT/ m-Ullevaal (N.=60) or to MICT (N.=60) group.

METHODS

Functional exercise capacity (FEC) of the eligible subjects was evaluated through 6-minute walk test (6MWT) and peak oxygen uptake. Blood samples were drawn at baseline, after 12 weeks follow-up for analyses of C-reactive protein (CRP), tumor necrosis factor-α (TNFα) and cellular adhesion molecules (CAM).

RESULTS

Significant decreases in the serum levels of CRP (P=0.029), TNF-α (P=0.036), and vascular cell adhesion molecule-1 (VCAM-1) (P=0.040), were observed after 48 training sessions in the group-based HIAIT/m-Ullevaal intervention, except for intercellular adhesion molecule-1 (ICAM-1), which was higher in the MICT (P=0.034). FEC was significantly inversely related to CRP (r=-0.72, P<0.05), and the levels of VCAM-1 (r=-0.68, P<0.05).

CONCLUSIONS

Both group-based CR interventions (HIAIT/m-Ullevaal and MICT) significantly reduced the serum levels of CRP, TNF- α, ICAM-1 and VCAM in patients with CHF. However, selected proinflammatory biomarkers changes and CAMs favorably decreased in the group-based HIAIT/m-Ullevaal intervention. The responses on serum levels of proinflammatory biomarkers and CAMs are dependent upon the type, intensity, and CR intervention duration.

CLINICAL REHABILITATION IMPACT

The group-based high-intensity aerobic interval training reduces significantly the proinflammatory biomarkers and cellular adhesion molecules in patients with chronic heart failure.

Musculoskeletal Pain and Musical Performance in First and Second Violinists of Professional Youth Chamber Orchestras: A Comparative Study

OBJECTIVE

First and second violinists in orchestras use identical instruments, but the motor patterns used to execute the different notes may vary between the two groups and the biomechanical gestures may influence musculoskeletal complaints. The primary objective of this study was to compare the pain intensity and interference in musical performance of first and second violinists of professional youth chamber orchestras. Second, to investigate the correlation between pain and the musical practice profile in this population.

METHODS

This cross-sectional study enrolled 74 violinists, aged 12 to 17 years, from three professional youth chamber orchestras in Brazil. Participants completed a validated self-administered questionnaire, the Musculoskeletal Pain Intensity and Interference Questionnaire for Musicians-Brazilian version (MPIIQM-Br). Variables related to musical practice profiles were also recorded. Data analysis applied t-tests for independent samples and Pearson's correlation coefficient.

RESULTS

The sample of first violinists (n=39) presented 23 males and 16 females, and the second violinists (n=35) included 23 females and 12 males. The mean age was 13.9 yrs (SD 1.1) and 14.1 yrs (1.0) for the first and second violinist groups, respectively. Most participants (n=66, 89%) reported pain in at least one moment of their career, and 54 (76%) reported pain at the time of data collection. A higher pain prevalence was identified in the right shoulder (37.7%), in 28.2% of the second violinists and 9.4% of the first. The second violinists presented higher scores for most variables related to pain intensity and pain interference in performance (p < 0.05). A correlation was observed between time working at a professional level and the number of affected areas on the body pain map (r=0.30; 95% CI 0.23-0.42) and between the hours of daily practice and the number of affected areas on the body pain map (r=0.39; 95% CI 0.29-0.45).

CONCLUSION

Second violinists had more complaints of pain and difficulty in playing their instrument compared to the first violinists. The study also found a correlation between the number of body areas with pain complaints and variables linked to the violinists' practice profile.

On- vs off-hours primary percutaneous coronary intervention: a single-centre experience

Introduction

In ST-segment elevation myocardial infarction (STEMI) patients, emergency medical system delays importantly affect outcomes. The effect of admission time in STEMI patients is dubious when percutaneous coronary intervention (PCI) is the preferred reperfusion strategy.

Aims

The authors aimed to retrospectively describe the association between admission time and STEMI patient's care standards and outcomes.

Methods

Characteristics and outcomes of 1222 consecutive STEMI patients treated in a PCI-centre were collected. On-hours were defined as admission on non-national-holidays from Monday to Friday from 8 AM to 6 PM. Time delays, in-hospital and one-year all-cause mortality were assessed.

Results

A total of 439 patients (36%) were admitted on-hours and 783 patients (64%) were admitted off-hours. Baseline characteristics were well-balanced between groups, including the percentage of patients admitted in cardiogenic shock (on-hours: 4.6% vs off-hours 4%; p=0.62).

Median emergency system dependent time to reperfusion (i.e. first-medical contact to reperfusion) did not differ between the two groups (on-hours: 120 min vs. off-hours 123 min, p=0.54). The authors observed no association between admission time and in-hospital mortality (on-hours: 5% vs. off-hours 4.9%, p=0.90) or 1-year mortality (on-hours: 10% vs. off-hours 10%, p=0.97).

In patients admitted directly in the PCI-centre, median time from first-medical contact to reperfusion (on-hours: 87 min vs off-hours: 88 min, p=0.54), in-hospital mortality (on-hours: 4% vs off-hours: 7%, p=0.30) and 1 year mortality (on-hours: 9% vs off-hours: 13%, p=0.27) did not differ between the two groups.

Survival analysis showed no survival benefit of on-hours PCI over off-hours PCI (HR 1.01; 95% CI [0.77–1.46], p=0.95).

Conclusion

In a contemporary well-organized emergency network, STEMI patients admission time in the PCI-centre was not associated with reperfusion delays or increased mortality.

Funding Acknowledgement

Type of funding sources: None. Kaplan-Meier curve

P–135 Artificial neural networks (ANNs) for live birth prediction in frozen embryo transfers: the strength of post-warmed blastocyst dynamics

Study question

Does the post-warmed blastocyst dynamics have an impact over the likelihood of achieving a live birth?

Summary answer

Variables related to dynamics of vitrified/warmed blastocysts have shown a greater effect on the live birth prediction than only embryo morphological quality through artificial intelligence.

What is known already

Morphological dynamics of vitrified/warmed blastocysts were described by Coello et al., in 2017. The investigated markers were the thickness of zona pellucida (µm) and blastocysts area (µm2) after warming and before transfer, the area of the inner cell mass (µm2), time of initiation of reexpansion (in minutes), and presence of collapse or contraction. They found a correlation between blastocyst reexpansion and implantation rate and developed a hierarchical model for implantation prediction. In our study, we evaluated the post-warmed blastocyst dynamics for live birth prediction by using novel artificial intelligence techniques.

Study design, size, duration

This retrospective analysis included 415 vitrified/warmed blastocysts with known live birth data. Blastocysts after warming were placed in EmbryoScope (Vitrolife) immediately until embryo transfer. Embryo evaluation and selection were performed by senior embryologists according to fresh blastocyst morphology (before vitrification). Then, parameters related to post-warmed blastocyst dynamics were calculated. Finally, these variables and the embryo morphological grade before the vitrification were used as input data for ANNs optimized with genetic algorithm for live birth prediction.

Participants/materials, setting, methods

Blastocysts were vitrified and warmed by the Cryotop method (Kitazato,Biopharma). During the period between the warming procedure and the embryo transfer, the following variables were measured with the drawing tools provided by the EmbryoViewer workstation: zona pellucida thinning (µm), blastocyst expansion (um) and the speed of these two events (µm/h). Finally, multilayer perceptron neural networks were trained with data of 331 embryos by using the backpropagation learning algorithm and tested with data of 84 embryos.

Main results and the role of chance

We trained and tested three architectures of ANNs with different input variables as follows: post-warmed variables (thinning of the zona pellucida, blastocyst expansion, thinning speed and expansion speed) and morphological grade (A, B or C) for ANN1, only post-warmed variables for ANN2 and only morphological grade for ANN3. The highest success rate when ANNs classified embryos as positive and negative live birth (LB+ and LB-) was achieved by combining post-warmed variables and morphological grade before embryo vitrification. The general accuracies for the blind tests were: 73.8% for ANN1, 66.7% for ANN2 and 71.4% for ANN3. Likewise, this combination achieved the highest AUC on test dataset to predict LB- (0.76 for ANN1, 0.74 for ANN2 and 0.67 for ANN3). However, the ANN2 trained with only post-warmed variables showed the best capacity to predict LB+ with an AUC of 0.73 (versus 0.46 for ANN1 and 0.5 for ANN3).

Limitations, reasons for caution

The main limitation is the subjectivity of manual annotations, although only one embryologist participated in this task.

Wider implications of the findings: The dynamics of vitrified/warmed blastocysts prior to embryo transfer could be more relevant variables than the morphological quality on day 5 before the cryopreservation. The analysis of embryo behavior after warming could improve clinical outcomes in frozen embryo transfers.

Trial registration number

none

Predictors of functional capacity as measured by the Glittre activities of daily living test in women with rheumatoid arthritis

Although pulmonary involvement is the most common extra-articular manifestation of rheumatoid arthritis (RA), traditional pulmonary function tests (PFTs) do not show a good correlation with the field tests usually performed in these patients. In recent decades, measurement of ventilation distribution heterogeneity through the nitrogen single-breath washout (N₂SBW) test and evaluation of functional capacity during exercise using the Glittre activities of daily living test (GA-T) have been increasingly used. Therefore, the objective of this study was to evaluate predictors of GA-T outcomes in women with RA considering demographic, anthropometric, clinical, functional variables, and chest computed tomography (CT) findings. Forty-three women with RA underwent the GA-T, the N₂SBW test, spirometry, measurement of the diffusing capacity for carbon monoxide (DLco), measurement of respiratory muscle strength, and evaluation of physical function of the lower and upper limbs through the Health Assessment Questionnaire Disability Index (HAQ-DI). Chest CT scans were analyzed retrospectively. The GA-T time showed significant correlations with the DLco (r_s=-0.397, P=0.008), forced vital capacity/DLco (r_s=0.307, P=0.044), phase III slope of the N₂SBW test (SIIIN₂, r_s=0.644, P<0.0001), and the HAQ-DI (r_s=0.482, P=0.001). Disease extent as assessed by chest CT was associated with the GA-T time. On multiple regression analysis, the SIIIN₂ and HAQ-DI were the only predictors of the GA-T time, explaining 40% of its variability. Thus, ventilation distribution heterogeneity and worse physical function substantially explain the variability in GA-T time in women with RA and varying extents of disease on chest CT.

Craniocervical Posture Assessed With Photogrammetry and the Accuracy of Palpation Methods for Locating the Seventh Cervical Spinous Process: A Cross-sectional Study

OBJECTIVE

The purpose of this study was to compare craniocervical posture assessed by photogrammetry using 2 distinct palpation methods for locating the spinous process of the seventh cervical vertebra (C7SP).

METHODS

This cross-sectional study was conducted in 2 phases. In phase I (n = 42), the assessor's accuracy in locating the C7SP using the flexion-extension and the modified thorax-rib static methods was compared to radiography. In phase II (n = 68), the craniocervical posture was analyzed with photogrammetry after palpation using the 2 methods. Neck pain intensity and disability were also determined.

RESULTS

The accuracy in locating the C7SP was higher using the modified thorax-rib static method (67%, 95% confidence interval [CI], 55-79) compared to the flexion-extension method (38%, 95% CI, 26-50, P = .016). Lower values of the craniocervical angle were obtained with the flexion-extension method than the modified thorax-rib static method (mean difference = -1.1°, 95% CI, -1.6 to -0.6, P < .001). However, both palpation methods resulted in similar classifications of participants as with or without forward head posture (P = .096). Weak correlations were observed between the craniocervical angle and neck pain intensity (ρ = -0.088 and -0.099, respectively) and disability (ρ = -0.231 and -0.249, respectively).

CONCLUSION

Craniocervical angles obtained using palpation methods with different accuracies were different, although the magnitude of the difference was insufficient to lead to different classifications of a forward head posture in adults with mild neck pain and disability. Craniocervical posture was weakly correlated with neck-pain intensity and disability.

Two new species of Collembola (Arthropoda: Hexapoda) from Minas Gerais, Brazil

Two new species of Collembola are described, full body chaetotaxy is given. Ptenothrix dalii sp. nov. and Seira pietata sp. nov. were originally found in metalogenic areas covered with transitional vegetation of savanna and forest in Minas Gerais, Southeastern Brazil. Ptenothrix dalii sp. nov. is part of the "gracilis-group" of species, with large, blunt macrochaetae on head and body. Seira pietata sp. nov. is part of the "andensis-group" of species, lacking macrochaeta on abdominal segment I.

Electrome alterations in a plant-pathogen system: Toward early diagnosis

This work aimed to verify the existence of patterns on the electrophysiological systemic responses of tomato plants inoculated with a pathogenic fungus in an environment with controlled light and temperature. Electrical signalling was measured before and after inoculation in the same plants, and data were analysed with time series techniques and approximate multi-scale entropy (ApEn). Machine learning algorithms were utilised in order to classify data before and after infection throughout the five days of experiments. The obtained results have shown that it is possible to distinguish differences in the plant's electrome activity before and after the fungus inoculation. In some cases, we have found scale invariance quantified by the power law decay in the distribution histogram. We also found a higher degree of internal organisation quantified by ApEn. The results of the classification algorithms achieved higher accuracy of infection detection at the initial stage of pathogen recognition by the plant. Besides, this study showed evidence that long-distance electrical signalling is likely involved in the plant-pathogen interaction, since signals were obtained in the stem and the inoculum applied on the plant leaves. This might be useful for the early detection of plant infections.

P5521Door-to-balloon time and mortality of a PCI centre: how crucial can 30 minutes be for our STEMI patients?

Introduction

STEMI time delays have been presented as an indicator of quality of care. Considering the system delay, the guidelines of European Society of Cardiology (ESC) and American Heart Association (AHA) for the management of STEMI patients (pts) diverge regarding the maximum time from STEMI diagnosis to wire crossing in pts presenting at primary PCI (pPCI) hospitals (≤60min versus ≤90min, respectively).

Objective

To compare the prognosis between pts presenting at pPCI hospital with maximum time from STEMI diagnosis to wire crossing of ≤60min and patients with times between 61 and 90min.

Methods

The records of 1679 STEMI pts admitted consecutively in our coronary care unit during six years were analysed retrospectively. Of this pts, 341 (20%) were admitted directly in a PCI centre and 1338 (80%) were rescued by an emergency medical system or presented to a non-PCI centre. Pts that presented at PCI centre were divided into two groups: group 1 – STEMI pts with maximum time from STEMI diagnosis to wire crossing of ≤60min (n=202,69%); group 2 – STEMI pts with times 61–90 min (n=91,31%). Pts with time from STEMI diagnosis to wire crossing >90min were excluded. Primary endpoints were the occurrence of death at 6 months and 1 year; follow-up was completed in 98% of pts.

Results

Group 2 pts were older (60±14 vs 67±143, p<0.001), with higher proportion of women (14.9% vs 25.3%; p=0.026), hypertension (45.5% vs 61.5%, p=0.035), diabetes (17.1 vs 24.4%, p=0.005) and presented more frequently Killip 4 at admission (2.1% vs 12.5%, p=0.003). Group 1 pts had higher proportion of smokers (62.2% vs 49.4%, p=0.03). Patient delay was statistically higher in group 2 (Mdn (h) 3.8±3.5 vs 5±2, p<0.001), as was the system delay (Mdn (min) 45±9 vs 74±8, p<0.001). In-hospital mortality (3.8% vs 5.1%, p=0.42) wasn't different between groups, but at 1-month (3.8% vs 10.3%, p=0.05), 6-months (4.4% vs 12.8%, p=0.02) and 1-year mortality (5% vs 15.4%, p=0.008) was higher in group 2. In multivariate analysis and after adjusting for different baseline characteristics, pts who complied with the recommended times according to the 2017 ESC guidelines had lower risk mortality at 1 year compared to group 2 [HR 0.42, 95% CI (0.23–0.74), p=0.006].

Conclusion

In patients presenting at this PCI centre, complying with the 2017 ESC STEMI guidelines in order to reduce the system delay to ≤60min was crucial, since pts who were reperfused within this recommended time had lower mortality rates.

Patients with Subacromial Pain Syndrome Present no Reduction of Shoulder Proprioception: A Matched Case-Control Study

BACKGROUND

Shoulder pain is common among patients with musculoskeletal pain and the prevalence of patients with subacromial pain syndrome (SAPS) is high. Despite the high prevalence, there is a lack of an extensive evaluation of the proprioception acuity in patients with SAPS. Knowledge of the proprioceptive deficit would assist clinicians in the proper treatment and may offer an alternative explanation for the mechanisms underlying SAPS, which are poorly understood.

OBJECTIVE

To compare the proprioceptive function of the shoulder in patients with SAPS and matched controls.

STUDY DESIGN

Matched case-control study.

SETTING

Physical Functional Rehabilitation Service of an outpatient clinic.

PARTICIPANTS

A total of 32 consecutive patients with SAPS who sought physical therapy for shoulder pain and 32 healthy participants (control group) matched for age, sex, and handedness.

INTERVENTIONS

All participants completed a questionnaire containing sociodemographic information, pain intensity and characteristics, the Numerical Pain Rating Scale, and the Shoulder Pain and Disability Index.

MAIN OUTCOME MEASUREMENTS

The proprioceptive assessment was performed through kinesthesia, passive joint position sense (PJPS), and the active joint position sense (AJPS).

RESULTS

The groups showed no statistically significant differences in kinesthesia, PJPS, and AJPS for internal or external rotation. The proprioceptive acuity was not associated with pain intensity or functional disability in patients with SAPS.

CONCLUSIONS

Participants with SAPS did not present proprioceptive deficits in a pain-free motion of medial and lateral rotation when compared to their matched controls. The proprioceptive deficit may not be involved with the mechanisms underlying SAPS and seems not to interfere with the clinical outcomes of patients with SAPS.

LEVEL OF EVIDENCE

Level III.

Ventilation distribution, pulmonary diffusion and peripheral muscle endurance as determinants of exercise intolerance in elderly patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a progressive and disabling disease that has been associated with aging. Several factors may potentially impair performance during exercise in elderly patients with COPD. This study was conducted to evaluate what characteristics related to lung function, peripheral muscle strength and endurance can predict the performance of elderly patients with COPD during cardiopulmonary exercise testing (CPET). Forty elderly patients with COPD underwent resting lung function tests, knee isokinetic dynamometry, and CPET. Three models were developed to explain the variability in peak oxygen uptake (VO(2) peak) after controlling for age as an independent confounder. The pulmonary function model showed the highest explained variance (65.6 %); in this model, ventilation distribution (p<0.001) and pulmonary diffusion (0.013) were found to be independent predictors. Finally, the models that included the muscle strength and endurance variables presented explained variances of 51 % and 57.4 %, respectively. In these models that involved muscular dysfunction, however, only the endurance variables were found to be independent predictors (p<0.05). In conclusion, ventilation distribution and pulmonary diffusion, but not the degree of airway obstruction, independently predict CPET performance in elderly patients with COPD. In addition, peripheral muscle endurance, but not strength, also predicts CPET performance in these subjects.

Pragmatic Combinations of Acupuncture Points for Lateral Epicondylalgia are Unreliable in the Physiotherapy Setting

This study describes the reliability of pragmatic combinations of acupuncture points for lateral epicondylalgia (LE) as prescribed by physiotherapists who were experts in acupuncture. Raters (n = 14; 33-59 years) independently prescribed acupuncture points for 30 simulated human patients with LE who were surveyed via a printed questionnaire. The frequency and cooccurrence of acupuncture points prescribed for patients with lateral epicondylitis were assessed. Absolute agreement and Light's kappa (κ_Light) with 95% confidence interval (CI) were used to quantify the interrater agreement. Raters prescribed 103 unique acupuncture points in different combinations with a median (min-max) of 5 (0-11) acupuncture points. The most prescribed acupuncture point was LI-11 (297 of 420; 71%), and the most common cooccurring acupuncture points were LI-11 and LI-4 (160 of 420; 38%). The absolute agreement for prescribing the acupuncture points ranged from 70% (point GB-20) to 0% (points LI-10, SP-6, LI-11, GB-34, LI-12, and LI-4). Point LR-3 showed the highest interrater reliability for prescribing the acupuncture points [κ_Light = 0.112, 95% CI = (0.055-0.194)], whereas point LI-4 showed the lowest reliability [κ_Light = -0.003, 95% CI = (-0.024 to 0.024)]. These findings suggest that pragmatic prescriptions of acupuncture points for LE are unreliable among physiotherapists who are experts in acupuncture. Explicit, high-level evidence-based rules for prescribing and teaching combinations of acupuncture points for LE are warranted.

Osmotic stress decreases complexity underlying the electrophysiological dynamic in soybean

Studies on plant electrophysiology are mostly focused on specific traits of single cells. Inspired by the complexity of the signalling network in plants, and by analogy with neurons in human brains, we sought evidence of high complexity in the electrical dynamics of plant signalling and a likely relationship with environmental cues. An EEG-like standard protocol was adopted for high-resolution measurements of the electrical signal in Glycine max seedlings. The signals were continuously recorded in the same plants before and after osmotic stimuli with a -2 MPa mannitol solution. Non-linear time series analyses methods were used as follows: auto-correlation and cross-correlation function, power spectra density function, and complexity of the time series estimated as Approximate Entropy (ApEn). Using Approximate Entropy analysis we found that the level of temporal complexity of the electrical signals was affected by the environmental conditions, decreasing when the plant was subjected to a low osmotic potential. Electrical spikes observed only after stimuli followed a power law distribution, which is indicative of scale invariance. Our results suggest that changes in complexity of the electrical signals could be associated with water stress conditions in plants. We hypothesised that the power law distribution of the spikes could be explained by a self-organised critical state (SOC) after osmotic stress.

Sensitivity for palpating lumbopelvic soft- tissues and bony landmarks and its associated factors: A single-blinded diagnostic accuracy study

BACKGROUND

Evidence on the diagnostic performance of palpatory methods and possible confounding factors is scarce.

OBJECTIVES

To examine the sensitivity of palpatory methods for location of lumbopelvic landmarks and to assess its association with personal characteristics.

METHODS

Eighty-three participants (41 men, 55.6 (16.5) years, 25.9 (4.8) kg/m2 [mean (SD)]) were enrolled in this single-blinded study. Fourteen body and softy-tissue landmarks were sequentially palpated from the spinous process of L4 to the ischial tuberosity. CT-scan images were used to assess what landmark was located.

RESULTS

Sensitivity for location was in range 22-86% for soft-tissues and 26-69% for bony landmarks. Reduction in sensitivity was observed from the quadratus lumborum to the inferior and lateral angle of the sacrum (86-26% and 75-33%, left and right sides, respectively). Palpations of L4 and L5 spinous processes were systematically more cephalic than other landmarks. Gender was weakly correlated to almost all landmarks (rp⁢b= 0.333 or weaker). Body mass index was weakly correlated to the accurate location of ILAS and quadratus lumborum, great trochanter, PSIS, and piriformis (rp⁢b=-0.307 or weaker).

CONCLUSIONS

Systematic and propagation errors were present using sequential palpatory methods. Palpation in men was more sensitive and higher BMI was associated with lower sensitivity for lumbopelvic landmarks.

Characteristics and prevalence of musculoskeletal injury in professional and non-professional ballet dancers

BACKGROUND:

Ballet is a high-performance activity that requires an advanced level of technical skills. Ballet places great stress on tendons, muscles, bones, and joints and may act directly as a trigger of injury by overuse.

OBJECTIVES:

1) to describe the main types of injuries and affected areas related to classical ballet and 2) to compare the frequency of musculoskeletal injuries among professional and non-professional ballet dancers, considering possible gender differences among the professional dancers.

METHOD:

A total of 110 questionnaires were answered by professional and non-professional dancers. The questionnaire contained items related to the presence of injury, the regions involved, and the mechanism of the injury.

RESULTS:

We observed a high frequency of musculoskeletal injuries, with ankle sprains accounting for 69.8% of injuries in professional dancers and 42.1% in non-professional dancers. Pirouettes were the most frequent mechanism of injury in professional dancers, accounting for 67.9% of injuries, whereas in the non-professional dancers, repetitive movement was the most common mechanism (28.1%). Ankle sprains occurred in 90% of the women's injuries, and muscle sprains occurred in 54.5% of the men's injuries. The most frequent injury location was the ankle joint in both sexes among the professional dancers, with 67.6% in women and 40.9% in men.

CONCLUSIONS:

The identification of the mechanism of injury and time of practice may contribute to better therapeutic action aimed at the proper function of the dancers' bodies and improved performance by these athletes.

Home-based exercise program in TSP/HAM individuals: a feasibility and effectiveness study

Objective

To investigate the feasibility and effectiveness of a home-based exercise program in TSP/HAM individuals.

Methods

Twenty-three TSP/HAM individuals divided in two groups according to Timed Up and Go (TUG) score (<20s vs ≥20s) performed a 20-week home-based exercise program. The primary outcomes were exercise adherence, maximum voluntary isometric contraction of lower limbs (MVIC), Barthel Index and SF-36. Secondary outcomes were adverse effects and barriers to exercise practice.

Results

MVIC and the social functioning domain in SF-36 improved significantly in TUG <20s group. The individuals in the TUG ≥20s group improved significantly their physical functioning domain in SF-36. The total adherence to the 20-week home-based exercise program was 90%. There were mild to moderate adverse events related to exercise program. There were no adverse events related to MVIC test.

Conclusions

The home-based exercise program was feasible and effective in improving disability and quality of life in individuals with TSP/HAM.

Seated limits-of-stability of athletes with disabilities with regard to competitive levels and sport classification

In this study, we asked whether wheelchair rugby (WR) classification and competitive level influence trunk function of athletes with disabilities, in terms of seated limits-of-stability (LoS). Twenty-eight athletes were recruited from international- and national-level WR teams, with each group exhibiting marked differences in years of sports practice and training volume. Athletes were also distributed into three groups according their classification: low-point (0.5-1.5-point); mid-point (2.0-2.5-point); and high-point (3.0-3.5-point). Athletes were asked to sit on a force platform and to lean the body as far as possible in eight predefined directions. Center of pressure (COP) coordinates were calculated from the ground reaction forces acquired with the force platform. LoS were computed as the area of ellipse adjusted to maximal COP excursion achieved for the eight directions. ANOVAs reveal that LoS were not different when international- and national-level players were compared (P=.744). Nevertheless, LoS were larger in players from the high-point group than from the low-point group (P=.028), with the mid-point group being not different from both (P>.194). In summary, (i) competitive level does not impact LoS measures and (ii) LoS are remarkably distinct when comparing both extremes of the WR classification range. Our results suggest that, as a training-resistant measure, LoS could be a valid assessment of trunk impairment, potentially contributing to the development of an evidence-based WR classification.

Determination of functional prognosis in hospitalized patients following an intensive care admission

AIM

To investigate the factors associated with the functional progress of hospitalized patients following an intensive care admission.

METHODS

Retrospective study including data from a cohort of 198 hospitalized patients following an intensive care admission and not requiring mechanical ventilation in a single tertiary referral hospital. A generalized linear model was used to identify the main effects of clinical and demographic variables on the outcomes of functionality (KATZ Index of Independence in Activities of Daily Living) and muscle strength (MRC Scale). The covariates identified as independent predictors were analysed using the receiver operating characteristic curves. The analysis differentiated the periods in the intensive care unit (ICU), in the Ward (WARD) and the total time of hospital stay (TOT).

RESULTS

Considering the functional outcome (ΔKATZ), the variables that significantly contributed to the model (P < 0.05) were the KATZ and MRC on admission, age, sepsis (no), and total length of stay (TLS). Regarding the muscle strength outcome model (ΔMRC), the predictors were MRC on admission, Simplified Acute Physiology Score III, previous stroke, TLS, and sex (female). The variable age (AUC = 0.664) discriminated the ΔKATZ_ICU. The variables age (AUC = 0.712), KATZ in ICU (AUC = 0.590) and on ward admission (AUC = 0.746), and MRC on ward admission (AUC = 0.721) were discriminative for ΔKATZ_WARD. For ΔKATZ_TOT the variables KATZ on ICU admission (AUC = 0.621) and TLS (AUC = 0.617) were discriminative. For ΔMRC_ICU the variables SAPSIII (AUC = 0.661) and MRC on ICU admission (AUC = 0.653) were discriminative. MRC on ICU (AUC = 0.681) and ward admission (AUC = 0.553) were discriminative for ΔMRC_WARD. TLS (AUC = 0.649) and MRC on ward admission (AUC = 0.696) discriminative for the ΔMRC_TOT.

CONCLUSION

Specific functional, clinical and demographical variables at ICU admission are associated with the functional prognosis during the hospitalization period.

Kinematic mapping reveals different spatial distributions of center of pressure high-speed regions under somatosensory loss

The spatial distribution of center-of-pressure speed during postural tasks and its changes due to somatosensory constraint (temporary ischemic hypoxia on ankle/feet) were investigated in young, healthy subjects (n = 13). A single high-speed region in the central region of the statokinesigram was observed during postural tasks with full sensory information. A significant increase in the quantity of high-speed regions was observed during ischemia and somatosensory constraint, whereas a significant increase in the quantity of high-speed regions localized more distant to the center of center-of-pressure area occurred under somatosensory constraints, suggesting a redirection of center-of-pressure trajectory to adjust the position of the center of mass with respect to the egocentric reference of balance.

Virulence factors and infection ability of Pseudomonas aeruginosa isolates from a hydropathic facility and respiratory infections

AIMS

To compare the virulence pool and acute infection ability of Pseudomonas aeruginosa isolates from a hydropathic facility, used to treat respiratory conditions by inhalation of untreated natural mineral water, with clinical isolates from respiratory infections.

METHODS AND RESULTS

Pseudomonas aeruginosa isolates from a hydropathic facility and from respiratory infections were typed by pulsed-field gel electrophoresis. Nonclonal representatives of each population were selected. 18 virulence-encoding genes were screened by polymerase chain reaction and statistically compared by multiple correspondence analysis. Homogeneous distribution of genes between populations but higher genetic association in aquatic isolates was observed, as well as distinct virulence pool according to location in the water system. Acute infection ability of selected isolates from each population, in Galleria mellonella model, showed lower LD50 of the majority of the hydropathic isolates and significant variations in LD50 of biofilm isolates from different equipments.

CONCLUSIONS

Hydrotherapy Ps. aeruginosa isolates present similar virulence to isolates from respiratory infections. Hydrotherapy users may be exposed to different microbiological risks when using different treatment equipments.

SIGNIFICANCE AND IMPACT OF THE STUDY

Twenty-one million people use hydropathic facilities in Europe, and the majority present risk factors to pneumonia. This study demonstrates the health risk associated with this practice. Revision of European regulations should be considered.

Role of dermatomes in the determination of therapeutic characteristics of channel acupoints: a similarity-based analysis of data compiled from literature

Background

Analysis of the relationship between the nervous system anatomy and the therapeutic characteristics of all acupuncture points in the channel network may provide new insights on the physiological mechanisms underlying acupuncture stimulation for prevention, treatment, and rehabilitation purposes. This study investigates the association between the similarity of acupoints’ dermatomes, traditional actions, and contemporary indications.

Methods

Channel acupoints had their characteristics annotated from a literature review of four topographic atlases of Chinese medicine and one atlas of human anatomy: initials of the channel’s name (n = 14), sequential number in the channel (n = 67), acupoint’s name (n = 361), dermatomes related to perpendicular needle insertion (n = 31), traditional actions (n = 848), and contemporary indications (n = 1143). Jaccard’s similarity coefficient quantified the similarities between dual acupoints. All dual acupoints were evaluated to generate similarity matrices for each nominal variable. Cross-tables were generated by simultaneous classification of variables into levels of similarity with respect to: dermatomes versus traditional actions, dermatomes versus contemporary indications, and traditional actions versus contemporary indications. Goodman-Kruskal γ and Rousson γ*² were calculated based on cross-tables, bootstrap and permutated samples to evaluate the association and determination coefficient between variables, respectively.

Results

Significant associations were observed between levels of similarities of dermatomes and traditional actions (γ = 0.542; P < 0.001), dermatomes and contemporary indications (γ = 0.657; P < 0.001), and traditional actions and contemporary indications (γ = 0.716; P < 0.001). Similarities of dermatomes explained 16% of the variance of traditional actions and 25% of contemporary indications. Traditional actions explained 30% of the variance of contemporary indications. The association between traditional actions and contemporary indications was the highest one (γ = 0.716, 95% confidence interval (95% CI) = [0.715; 0.719]), followed by the association between dermatomes and contemporary indications (γ = 0.622, 95% CI = [0.621; 0.623]), and between dermatomes and traditional actions (γ = 0.446, 95% CI = [0.444; 0.447]), all with P < 0.001.

Conclusions

The similarity of dermatomes between dual acupoints partially determined the similarity of traditional actions and contemporary indications, therefore dermatomes partially determine the therapeutic efficacy of acupuncture.

Alzheimer random walk model: two previously overlooked diffusion regimes

A non-Markovian one-dimensional random walk model is studied with emphasis on the phase-diagram, showing all the diffusion regimes, along with the exactly determined critical lines. The model, known as the Alzheimer walk, is endowed with memory-controlled diffusion, responsible for the model's long-range correlations, and is characterized by a rich variety of diffusive regimes. The importance of this model is that superdiffusion arises due not to memory per se, but rather also due to loss of memory. The recently reported numerically and analytically estimated values for the Hurst exponent are hereby reviewed. We report the finding of two, previously overlooked, phases, namely, evanescent log-periodic diffusion and log-periodic diffusion with escape, both with Hurst exponent H=1/2. In the former, the log-periodicity gets damped, whereas in the latter the first moment diverges. These phases further enrich the already intricate phase diagram. The results are discussed in the context of phase transitions, aging phenomena, and symmetry breaking.

Weakly anomalous diffusion with non-Gaussian propagators

A poorly understood phenomenon seen in complex systems is diffusion characterized by Hurst exponent H ≈ 1/2 but with non-Gaussian statistics. Motivated by such empirical findings, we report an exact analytical solution for a non-Markovian random walk model that gives rise to weakly anomalous diffusion with H = 1/2 but with a non-Gaussian propagator.

Immediate effects of acupuncture on biceps brachii muscle function in healthy and post-stroke subjects

Background

The effects of acupuncture on muscle function in healthy subjects are contradictory and cannot be extrapolated to post-stroke patients. This study evaluated the immediate effects of manual acupuncture on myoelectric activity and isometric force in healthy and post-stroke patients.

Methods

A randomized clinical trial, with parallel groups, single-blinded study design, was conducted with 32 healthy subjects and 15 post-stroke patients with chronic hemiparesis. Surface electromyography from biceps brachii during maximal isometric voluntary tests was performed before and after 20-min intermittent, and manual stimulation of acupoints Quchi (LI11) or Tianquan (PC2). Pattern differentiation was performed by an automated method based on logistic regression equations.

Results

Healthy subjects showed a decrease in the root mean-squared (RMS) values after the stimulation of LI11 (pre: 1.392 ± 0.826 V; post: 0.612 ± 0.0.320 V; P = 0.002) and PC2 (pre: 1.494 ± 0.826 V; post: 0.623 ± 0.320 V; P = 0.001). Elbow flexion maximal isometric voluntary contraction (MIVC) was not significantly different after acupuncture stimulation of LI11 (pre: 22.2 ± 10.7 kg; post: 21.7 ± 9.5 kg; P = 0.288) or PC2 (pre: 18.8 ± 4.6 kg; post: 18.7 ± 6.0 kg; P = 0.468). Post-stroke patients did not exhibit any significant decrease in the RMS values after the stimulation of LI11 (pre: 0.627 ± 0.335 V; post: 0.530 ± 0.272 V; P = 0.187) and PC2 (pre: 0.601 ± 0.258 V; post: 0.591 ± 0.326 V; P = 0.398). Also, no significant decrease in the MIVC value was observed after the stimulation of LI11 (pre: 9.6 ± 3.9 kg; post: 9.6 ± 4.7 kg; P = 0.499) or PC2 (pre: 10.7 ± 5.6 kg; post: 10.2 ± 5.3 kg; P = 0.251). Different frequency of patterns was observed among healthy subjects and post-stroke patients groups (χ² = 9.759; P = 0.021).

Conclusion

Manual acupuncture provides sufficient neuromuscular stimuli to promote immediate changes in motor unit gross recruitment without repercussion in maximal force output in healthy subjects. Post-stroke patients did not exhibit significant reduction on the myoelectric activity and maximal force output after manual acupuncture and needs further evaluation with a larger sample.

Trial registration

Brazilian Clinical Trials Registry RBR-5g7xqh.

Validation of the Forced Oscillation Technique in the diagnostic of respiratory changes in patients with silicosis

Silicosis is a typical occupational respiratory disease characterized by irreversible alterations throughout the alveolar and interstitial structure. The objectives of this study were (1) investigate the potential of the Forced Oscillation Technique (FOT) in the analysis of the patients with silicosis, and (2) evaluate the ability of FOT to identify early alterations in the respiratory mechanics of these patients. Sixty-one volunteers were analyzed: 20 healthy subjects and 41 with silicosis; these, were divided into 4 groups according to spirometric results: normal spirometric exam (n = 11); mild obstruction (n = 20); moderate and severe obstruction (n = 10.). A significant (p〈0.0001) increase in total resistance (R0) and mean resistance (Rm) were observed, as well as a decrease in the dynamic compliance (p〈0.0003) and mean reactance (p〈0.000004). R0 and Rm obtained adequate accuracy for clinical use (>80%). FOT parameters adequately described the pathophysiological changes associated with silicosis and presented adequate accuracy for clinical use, indicating that this technique can be helpful in the evaluation respiratory mechanics in this disease.

Direct and specific identification of Cryptococcus neoformans in biological samples using fluorescently labelled DNA probes

Fluorescence in situ hybridisation (FISH) is a suitable technique for the rapid, reliable and cultivation-independent identification of microbial pathogens. This study describes the development of fluorescently labelled rRNA-targeted oligonucleotides and a FISH assay to detect and identify Cryptococcus neoformans in culture and biological samples. All C. neoformans reference and clinical isolates gave positive signals with the specific oligonucleotide probes, whereas all non-target yeast species gave negative reactions with the same probes. The assay was also successfully applied to the detection of C. neoformans cells in cerebrospinal samples from patients with clinical diagnosis of cryptococcosis. The described FISH-based assay revealed to be practical, sensitive and specific for the detection and identification of C. neoformans yeasts.

Anomalous diffusion in non-Markovian walks having amnestically induced persistence

We report numerically and analytically estimated values for the Hurst exponent for a recently proposed non-Markovian walk characterized by amnestically induced persistence. These results are consistent with earlier studies showing that log-periodic oscillations arise only for large memory losses of the recent past. We also report numerical estimates of the Hurst exponent for non-Markovian walks with diluted memory. Finally, we study walks with a fractal memory of the past for a Thue-Morse and Fibonacci memory patterns. These results are interpreted and discussed in the context of the necessary and sufficient conditions for the central limit theorem to hold.

Spontaneous symmetry breaking in amnestically induced persistence

We investigate a recently proposed non-Markovian random walk model characterized by loss of memories of the recent past and amnestically induced persistence. We report numerical and analytical results showing the complete phase diagram, consisting of four phases, for this system: (i) classical nonpersistence, (ii) classical persistence, (iii) log-periodic nonpersistence, and (iv) log-periodic persistence driven by negative feedback. The first two phases possess continuous scale invariance symmetry, however, log-periodicity breaks this symmetry. Instead, log-periodic motion satisfies discrete scale invariance symmetry, with complex rather than real fractal dimensions. We find for log-periodic persistence evidence not only of statistical but also of geometric self-similarity.

Simplified distributed-parameter model of brachial-radial arteries for noninvasive determination of mechanical characteristics of vessel

This paper proposes a simplified distributed-parameter model of the brachial-radial arteries segment for the determination of mechanical parameters of these arteries and compares it with a four-element Windkessel model. The comparison is performed using data collected noninvasively of pressure pulse waveforms at two different locations of the arterial segment, under physiological (normotensive) and pathological (primary hypertension) conditions. The results show, by Akaike Information Criterion, that the proposed model fits the real pressure pulse waveform better than classical Windkessel model, and that also gives mechanical parameters coherent with the clinical condition.

The effects of ligand chain length, salt concentration and temperature on the adsorption of bovine serum albumin onto polypropyleneglycol-Sepharose

The interaction thermodynamics associated with bovine serum albumin adsorption on polypropylene glycol (n=3)-Sepharose CL-6B and polypropylene glycol (n=7)-Sepharose CL-6B, using ammonium sulfate as the modulator was studied. Analysis of data under linear conditions was accomplished with the stoichiometric displacement retention model, preferential interaction approach and van't Hoff plots applied to HIC systems. Preferential interaction analysis indicated a strong entropic driving force under linear conditions, due to the release of a large amount of solvent on adsorption. In contrast, flow microcalorimetry under overloaded conditions showed that the adsorption of bovine serum albumin may be entropically or enthalpically driven. It is postulated that adsorption in the nonlinear region is influenced by the degree of water release, protein-protein interactions on the surface, reorientation of ligand, and conformational changes in the protein.

Determination of radial artery compliance can increase the diagnostic power of pulse wave velocity measurement

Pulse wave velocity (PWV) is an indicator associated with the arterial stiffness. Although this technique has been used in the diagnosis of systemic arterial hypertension (SAH), it cannot supply alone enough information about the pathogenesis of this disturbance. This paper aims to determine the compliance of brachial-radial arterial segment by applying a three-element windkessel model, and by using the same pressure waveforms acquired to calculate the PWV. The proposed method to determine the arterial compliance was evaluated with a physical simulation of the arterial system, where parameters were known, resulting in an estimation error of 0.73 x 10(-7) cm5 dyne(-1). In a clinical study the estimated compliance was statistically different (p < 0.01) in a controlled group ((3.12 +/- 3.53) x 10(-7) cm5 dyne(-1)) and in an SAH group ((1.04 +/- 0.74) x 10(-7) cm5 dyne(-1)). It was observed that the PWV value calculated using the maximum of the first derivative of the pressure waveform upstroke as characteristic points was the best correlated (r = -0.71) with the determined compliance. Because SAH normally results, among other causes. from a decreased arterial compliance the results suggest that the determined compliance could be used concomitantly with PWV to supply more diagnostic information about the pathogenesis of SAH.

Stochastic modeling approach to the incubation time of prionic diseases

Transmissible spongiform encephalopathies are neurodegenerative diseases for which prions are the attributed pathogenic agents. A widely accepted theory assumes that prion replication is due to a direct interaction between the pathologic (PrP(Sc)) form and the host-encoded (PrP(C)) conformation, in a kind of autocatalytic process. Here we show that the overall features of the incubation time of prion diseases are readily obtained if the prion reaction is described by a simple mean-field model. An analytical expression for the incubation time distribution then follows by associating the rate constant to a stochastic variable log normally distributed. The incubation time distribution is then also shown to be log normal and fits the observed BSE (bovine spongiform encephalopathy) data very well. Computer simulation results also yield the correct BSE incubation time distribution at low PrP(C) densities.

Metabolic responses to different glucose and glutamine levels in baby hamster kidney cell culture

In this work, a BHK21 clone producing a recombinant antibody/cytokine fusion protein was used to study the dependence of cell metabolism on the glucose and glutamine levels in the culture medium. Results obtained indicate that both glucose and glutamine consumptions show a Michaelis-Menten dependence on glucose and glutamine concentrations respectively. A similar dependence is also observed for lactate and ammonia productions. The estimated value of the Michaelis constant for the dependence of lactate production on glucose (KLacGlc) was 1.4 +/- 0.1 mM and for the dependence of ammonia production on glutamine (KAmmGln) was 0.25 +/- 0.11 mM and 0.10 +/- 0.03 mM, at glucose concentrations of 0.28 mM and 5.6 mM respectively. At very low glucose concentrations, the glucose to lactate yield decreased markedly, showing a metabolic shift towards lower lactate production. This metabolic shift was also confirmed by the significant increase in the specific oxygen consumption rate also observed at low glucose concentrations. Although it was highly dependent on glucose concentration, the oxygen consumption also increased with the increase in glutamine concentration. At very low glutamine concentrations, the glutamine to ammonia yield increased, showing a more efficient glutamine metabolism.