Function In Normal Subjects Research Articles

Abstract 8898: Gender Difference in Right Ventricular Diastolic Function in Normal Subjects

Background: Normative Doppler values and determinants for gender difference of right ventricular diastolic function in healthy subjects have not been fully elucidated. The purpose of this study is to verify the difference of right ventricular diastolic function between men and women at each age. Method: One hundred sixty nine male and 221 female in healthy subject, aged 20 to 90, were examined by both tricuspid inflow velocity and tricuspid annulus velocity by tissue Doppler imaging. All subjects were divided into 7 groups as 20s, 30s, 40s, 50s, 60s,70s, 80s depend on their age. Results :The tricuspid E velocity was significantly decreased with age(p<0.0001). But E velocitywas no differences significantly in all generation between men and women. The tricuspid A velocity was significantly increased with age(p<0.0001). But A velocity was no differences significantly in all generation between men and women (Table). Ratio of tricuspid E and A velocity (E/A) was significantly decreased with age.But no differences were observed in ratio of E/A in all generation between men and women. (20s: 2.0±0.6 vs 2.5±0.6 p=0.03,30s: 1.9±0.5 vs 2.1±0.5 p=NS, 40s: 1.6±0.4 vs 1.9±0.5 p=NS, 50s: 1.3±0.3 vs 1.5±0.4p=NS, 60s: 1.2±0.2 vs 1.2±0.3 p=NS, 70s: 1.1±0.3 vs 1.1±0.3 p=NS, 80s: 1.2±0.3vs 1.2±0.3 p=NS, total: 1.4±0.5 vs 1.5±0.6 p=NS). Early diastole velocity of tricuspid annulus (Ea) by tissue Doppler method was significantly decreased with age (p<0.0001). But Ea was no differences significantly in all generation between men and women (Table). Conclusions: Our results provide the normative Doppler values of right ventricular diastolic function for age decades. The assessment of right ventricular diastolic function obtained from Doppler method should be considered their age. There was no differences significantly of right ventricular diastolic function between men and women.

Effects of epoprostenol and sildenafil on right ventricular function in hypoxic volunteers: a tissue Doppler imaging study

Sildenafil and epoprostenol are effective therapies in pulmonary arterial hypertension (PAH). Both drugs increase cardiac output, which has been in part attributed to improved right ventricular (RV) contractility. We therefore used tissue Doppler imaging (TDI) to test whether sildenafil and epoprostenol might differently affect RV function in normal subjects before and after induction of acute hypoxic pulmonary hypertension. Ten healthy volunteers underwent this randomized, double-blind, placebo-controlled cross-over study. Echocardiographic measurements were obtained 60min after the intake of a placebo or 50mg sildenafil or under 8ng/kg/min iv epoprostenol, in normoxia or after 60min of hypoxic breathing (FIO(2) of 0.12). Right ventricular systolic function was assessed by systolic strain (ε), strain rate (SR), isovolumic contraction acceleration (IVA) and tricuspid annulus plane systolic excursion (TAPSE), and diastolic function by tricuspid annulus E/A ratio and isovolumic relaxation time related to RR interval (IRT/RR). Pulmonary artery pressure was calculated from the acceleration time of pulmonary flow and cardiac output from the left ventricular outflow tract flow-velocity. Hypoxia increased pulmonary vascular resistance (PVR) by 78%, did not affect indices of RV systolic function, decreased E/A and increased IRT/RR. Epoprostenol more than sildenafil increased cardiac output, apical ε and TAPSE, the latter in proportion to decreased PVR. In addition, apical SR was increased only by epoprostenol. None of the drugs affected IVA, basal SR, E/A and IRT/RR. These results are not suggestive of intrinsic positive inotropic effects of either sildenafil or epoprostenol at maximal doses tolerated by normal subjects.

Longitudinal Shortening Accounts for the Majority of Right Ventricular Contraction and Improves After Pulmonary Vasodilator Therapy in Normal Subjects and Patients With Pulmonary Arterial Hypertension

The right ventricle has a unique contraction pattern, with a greater portion of the shortening occurring in the longitudinal plane. However, the relative contributions of longitudinal and transverse shortening to overall right ventricular (RV) function have not been quantified. We sought to quantify the proportions of longitudinal and transverse shortening to RV function in normal subjects and in patients with pulmonary arterial hypertension (PAH) at baseline and following PAH-specific therapy. The normal cohort comprised 90 subjects with normal clinical echocardiograms, whereas the PAH cohort included 36 patients, of whom 25 had echocardiograms before and after initiation of PAH-specific therapy. Assessment of RV function included tricuspid annular plane systolic excursion, RV fractional area change (RVFAC), and relative change in RV area in longitudinal and transverse planes. Longitudinal fractional area change (LFAC) accounted for the majority of total RVFAC (77% ± 14%) in normal subjects. Among patients with PAH, longitudinal shortening still represented the majority of RVFAC, even though it was less than in normal subjects (63% ± 18%, P < .0001). Following PAH therapy, overall RV function improved (RVFAC, 30% ± 13% to 36% ± 9%; P = .026), solely because of an increase in longitudinal area change. As a result, the proportion of longitudinal shortening increased (LFAC, 58% ± 18% to 69% ± 17%; P = .002), whereas transverse shortening fell (transverse fractional area change, 42% ± 18% vs 31% ± 17%; P = .002). Longitudinal shortening accounts for the majority of RV contraction in normal subjects and patients with PAH, although less so in PAH. Improved RV function following pulmonary vasodilator therapy occurs solely from improvements in longitudinal contraction, suggesting that longitudinal shortening may represent the afterload-responsive element of RV functional recovery.

Learning effect of dark adaptation among normal subjects

To examine and quantify any change in the dark adaptation (DA) function of normal subjects due to learning effect on test-retest. Sixteen normal subjects (12 women, four men) whose ages ranged between 24 and 52years (mean 34.6 ± 6.7years) were studied. The interval period between test and retest ranged between 0.92 and 2.37months (mean 1.38 ± 0.40months). DA was measured with a Goldmann-Weekers (GW) dark adaptometer, and subjects were pre-adapted using a light intensity of 2,700cd/m(2) Ganzfeld background for 5 minutes. Exponential non-linear regression analysis was used to determine seven parameters of DA function. These were time of cone-rod break, cone and rod final thresholds, and magnitude of change and time constant of the cone and rod limbs. The mean cone-rod break time with 95% confidence intervals (CI) was 0.098 (CI: -0.527, 0.330) minutes faster on retest (p = 0.630)). Fourteen of the 16 subjects demonstrated an increase or 'worsening' of their final cone and rod thresholds on the second visit. The mean final threshold differences on retest for the cone limb was 0.105 (CI: 0.032, 0.179) log cd/m(2) (p = 0.008) and 0.093 (CI: -0.039, 0.225,) log cd/m(2) (p = 0.155) for the rod limb. The magnitude of change for the cone limb was 0.016 (CI: -0.122, 0.155) log cd/m(2) (p = 0.805) and -0.196 (CI: -0.435, 0.827) log cd/m2 (p = 0.518) for the rod limb, while the time constant on retest for the cone limb was -0.021 (CI: -0.128, 0.169) minutes, (p = 0.770) and 0.276 (CI: -0.424, 0.976) minutes (p = 0.410) for the rod limb. None of the DA parameters that were examined demonstrated a learning effect of clinical significance between test and retest. None of the changes in mean from test to retest for the seven parameters were found to be statistically significant, and the changes were clinically negligible. Therefore, any change among patients that may occur in dark adaptation between a visit interval may be considered real, and not due to the effect of learning.

P13-7 Objective evaluation of swallowing function of normal subjects and patients using surface electromyography: age effect and clinical usefulness

P13-7 Objective evaluation of swallowing function of normal subjects and patients using surface electromyography: age effect and clinical usefulness

Effects of high-dose insulin infusion on left ventricular function in normal subjects

Background. Only a few studies have reported on the effect of high-dose insulin (HDI) infusion on cardiac function in healthy volunteers. Methods. We studied ten healthy volunteers with low-dose dobutamine (LDD, 10 mug/kg/min) echo-cardio-graphy and HDI echocardiography (insulin administration for one hour) by volume and Doppler analysis. Results. During LDD, cardiac output increased from 5.7+/-1.3 l/min to 9.0+/-2.1 l/min (p<0.001) and during HDI from 5.5+/-1.2 l/min to 6.2+/-1.1 l/min (p=0.048). Increase was not only due to increase in frequency, which was only present in the LDD study, but also due to increase in stroke volume (from 82+/-15 ml to 110+/-23 ml, p<0.001 during LDD and from 82+/-16 ml to 93+/-24 ml, p=0.014 during HDI). The increase in stroke volume was the result of a decrease in end-systolic volume with an unchanged end-diastolic volume. Conclusion. High-dose insulin infusion results in increased cardiac output by improving systolic myocardial function. (Neth Heart J 2010;18:183-9.).

Can We Improve Sleep Quality by Changing the Way We Ventilate Patients?

Sleep is an integral part of daily life. Both disrupted andrestricted sleep adversely affect well-being and predisposeto chronic medical problems [1]. For example, in epide-miologic studies, women reporting 5 or fewer hours ofsleep per night are at significantly increased risk of incidentcardiovascular disease and diabetes over a 10-year timeperiod [2, 3].Critically ill mechanically ventilated patients have longbeen known to have poor sleep quality [4], but the potentialimportance of sleep disturbance in these patients is onlynow starting to be recognized [5, 6]. Sleep deprivation mayadversely affect respiratory, cognitive, cardiovascular,endocrine, and immune function in normal subjects [7–9];altered sleep architecture may be associated with anincreased incidence of delirium in ICU patients [10]. Fur-thermore, in the case of long-term positive-pressure ther-apy, adherence to the treatment may be influenced by howit affects sleep [11].There are numerous factors that adversely affect sleepquality in critically ill patients. Noise, nursing care, circa-dian rhythm disruption, and light exposure have all beenimplicated [12, 13], as have severity of illness andmedications [14]. Interest, however, has recently turnedtoward the mode and settings of mechanical ventilation as acause of sleep disturbance [15].Major causes of sleep disturbance associated withmechanical ventilation include patient-ventilator asyn-chronies [16], central apneas due to overventilation [17],and inadequate ventilatory support due to improper settingsor air leaks leading to increased respiratory effort [18].Therefore, there is a renewed interest in finding novel waysof adequately ventilating patients while minimizing sleepdisturbance.In a previous issue of Lung, Crisafulli et al. [19] pre-sented the findings of a pilot study comparing a newermode of noninvasive ventilation, average volume assuredpressure support (AVAPS), to noninvasive pressure sup-port (NIV-PS) therapy in nine stable hypercapnic COPDpatients. AVAPS differs from NIV-PS in its ability toensure more consistent minute ventilation by slowlyadjusting inspiratory positive airway pressure (IPAP) toachieve a preset tidal volume. Therefore, there is a theo-retical benefit in that this mode of ventilation couldimprove nocturnal ventilation in hypercapnic patients,leading to improvements in CO

A PHYSICO-MATHEMATICAL STUDY OF LUNG FUNCTION IN NORMAL SUBJECTS AND IN PATIENTS WITH OBSTRUCTIVE PULMONARY DISEASES.

A PHYSICO-MATHEMATICAL STUDY OF LUNG FUNCTION IN NORMAL SUBJECTS AND IN PATIENTS WITH OBSTRUCTIVE PULMONARY DISEASES.

Olfactory Evaluation Using a Self-Administered Odor Questionnaire

We evaluated a 20-item self-administered odor questionnaire for assessing olfactory function, proposed in 2003 by the Japan Rhinologic Society committee on olfaction tests. The 20-items selected based on results of olfactory studies in Japan were steamed rice, miso, seaweed, soy sauce, baked bread, butter, curry, garlic, orange, strawberry, green tea, coffee, chocolate, household gas, garbage, timber, stercus (shit), sweat, flower, and perfume. Subjects were 302 people —179 men and 123 women (average age: 35.7 years)— having no history of nasal or paranasal disease and tested between December 2004 and December 2007. Subjects were asked to score items as follows: “always smelled” (2 points); “sometimes smelled” (1 point); “never smelled” (0 points); or “unknown or no recent experience” (no score). Scores were calculated and represented using a percentage. Response was 99.3% (300/302), with two subjects excluded for reporting more than 10 “unexplainable” items. The mean score was 95.2% (n=300). Of the 302, 281 (93.0%) agreed on the number and 252 (83.4%) on the content of items. Scores correlated statistically significantly with those of a visual analogue scale (rs=0.501, p<0.0001, n=300). We concluded that the self-administered odor questionnaire is useful in assessing olfactory function in normal subjects. The next step will be to administer the questionnaire to diseased or otherwise compromised subjects to determine whether it is useful for clinically diagnosing such olfactory dysfunction.

Functional brain imaging with use of a new and powerful neuroimaging technique

Most of the information available on the human brain came from subjects who had sustained major head wounds, or who suffered from various mental disorders. By determining the extent of brain damage, and the nature of the loss of function, it was possible to infer which regions of the brain were responsible for which function. With the development of the imaging techniques of computerised tomography (CT) and magnetic resonance imaging it was possible to be more specific as to the location of damage in brain injured patients. The measurement of the electrical signals on the scalp, arising from the synchronous firing of the neurons in response to a stimulus, known as electroencephalography (EEG), opened up new possibilities in studying brain function in normal subjects. However it was the advent of the functional imaging modalities of positron emission tomography (PET), single photon emission computed tomography (SPECT), functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG) that led to a new era in the study of brain function. In this paper the mechanisms of the techniques mentioned above are outlined, together with an assessment of their strengths and weaknesses. Then an introduction to the Metabolism and Blood Flow in the Brain is given. This is followed by a more detailed explanation of functional MRI and how such experiments are performed.

Lack of Significant Association between Intima-Media Thickness in the Carotid Artery and Serum TSH Level. The Tromsø Study

Increased arterial wall intima-media thickness (IMT) is an early feature of atherosclerosis and has been reported to be altered in patients with thyroid dysfunction. The present study was performed to examine the relation between carotid artery intima-media thickness and possible variations in thyroid function in normal subjects using serum TSH as a surrogate index of thyroid function. A total of 2034 subjects (974 males) were studied, 1856 or whom were non-users of thyroxine. The subjects not taking thyroxine were classified into three groups, those with a low serum TSH (0.48 mIU/L (2.5 percentile, those with serum TSH from 0.48 to 4.16 mIU/L, and those with high serum TSH of >4.16 mIU/L (97.5 percentile). Carotid ultrasound was performed in each all 2034 subjects to determine IMT. Among those not taking thyroxine, subjects in the low serum TSH group had a higher mean IMT as compared to those in the normal and high serum TSH groups but the differences were not significant when adjusted for gender, age, smoking status, body mass index, systolic blood pressure and serum cholesterol (0.88 +/- 0.15 mm, 0.84 +/- 0.16 mm, and 0.84 +/- 0.24 mm respectively). Subjects taking thyroxine had significantly higher IMT than those not taking thyroxine (0.89 + 0.20 mm versus 0.84 + 0.17 mm, p<0.01). No significant relationship between carotid IMT and serum TSH levels was observed in normal, non thyroxine taking, subjects. Carotid IMT was increased in subjects taking thyroxine. Whether the increase in carotid IMT is due to thyroxine ingestion or underlying thyroid disease cannot be answered from the study.

The Effect of Auditory Stress on Perception of Intraesophageal Acid in Patients With Gastroesophageal Reflux Disease

Most patients with gastroesophageal reflux disease (GERD) report that stress exacerbates their symptoms, yet mechanisms underlying this association remain unknown. We sought to determine the effect of an acute laboratory stressor on perceptual and emotional responses to intraesophageal acid perfusion in healthy controls and patients with GERD. Forty-six patients with heartburn and 10 healthy controls underwent upper endoscopy and, if negative, pH monitoring. Assessment of psychologic factors and health-related quality of life was done by a questionnaire. Perceptual and emotional responses to intraesophageal acid at baseline, during auditory stress, and during an auditory control condition were determined using a randomized crossover design. Plasma levels of norepinephrine, adrenocorticotropic hormone, and cortisol were assessed. Twenty-nine subjects were identified as nonerosive reflux disease and 17 as erosive esophagitis. Quality of life, psychologic profile, and personality assessment variables were similar among the 2 patient groups and the controls. There was a significant reduction in mean lag time to initial symptom perception and an increase in mean intensity rating and mean acid perfusion sensitivity score in the 2 patient groups during the stress period, which was not seen during the control condition. Healthy controls demonstrated lack of a significant change in all parameters of stimulus response functions to acid, regardless of condition. Acute auditory stress can exacerbate heartburn symptoms in GERD patients by enhancing perceptual response to intraesophageal acid exposure. This greater perceptual response is associated with greater emotional responses to the stressor.

Killer Immunoglobulin Receptor (KIR) Negative NK Cells Exhibit Potent Alloreactivity Against Primary Leukemia Targets When Interrupting MHC Class I Interactions through NKG2A Blockade.

Effective therapeutic options are lacking for patients with primary refractory or relapsed acute myelogenous leukemia (AML). We have shown that adoptive transfer of haploidentical NK cells can result in complete remissions (25%) in patients with refractory disease but this procedure is still limited by a high failure rate. Based on the finding that 29±3% (n=26) of normal CD56dim NK cells are KIR− NKG2A+, we hypothesized that non-KIR class I MHC inhibitory receptors may play a bigger role than previously recognized in the cumulative integration of signals that determine whether leukemia targets are killed by NK cells. We studied the role of NKG2A and KIR inhibitory signals on primary AML and acute lymphoblastic leukemia (ALL) targets collected by therapeutic lymphapheresis. Blast susceptibility to fresh resting polyclonal allogeneic NK cells (enriched by CD3 depletion) and to NK cells activated with low pharmacologic doses of IL-2 for 72 hours was determined using flow cytometry based cytotoxicity assays and a degranulation assay using CD107a. The role of inhibitory signaling through class I MHC-recognizing receptors was tested by blocking interactions between receptor and cognate ligand using 1) a pan-MHC monoclonal antibody (mAb) (clone HP17-F) recognizing HLA-A, B, C and E, 2) an anti-KIR reagent (1-7F9 which blocks inhibitory KIR2DL1/L2/L3) currently in clinical trials (Novonordisk, Copenhagen) and 3) a mAb against NKG2A (clone Z199). Susceptibility to killing was defined as >10% lysis at an E:T ratio of 10:1. Two of 8 leukemias (25%) were lysed by resting allogeneic NK cells. NK cells activated with IL-2 (5U/ml) killed 7 of 8 targets (average increase of 13±2.2% lysis). In 3 AMLs killing was significantly enhanced by pan-MHC mAb blockade, but was less enhanced by anti-KIR blockade. NKG2A blockade alone also increased killing, and when added to anti-KIR blockade AML killing was equal to that obtained with MHC blockade. This suggests that non-KIR class I recognizing interactions were operant. Interestingly, anti-KIR blockade did significantly enhance killing of ALL targets suggesting that higher MHC expression (MFI 3-fold greater) may be a dominant factor to NK cell susceptibility in ALL. These findings support the notion that susceptibility to NK cell lysis is determined by interactions beyond just KIR and KIR-ligands. To explore this further KIR− NK cells were enriched with immunomagnetic bead separation (80% NKG2A+). AML target killing by these IL-2 activated KIR−NKG2A+ NK cells increased significantly after pan-MHC and NKG2A blockade (from an average baseline of 21% lysis to 34% for both), but no increase was seen with KIR blockade. This suggests that a significant proportion of normal NK cells are negatively regulated by KIR-independent mechanisms interacting with HLA-E. In summary, interrupting dominant NK cell receptor interactions with class I MHC ligands may lead to better strategies to treat AML and even ALL. NKG2A blockade may be a good target as it is highly expressed on virtually all NK cells reconstituting in the first 3 months after allogeneic HCT and it identifies NK cells with effector function in normal subjects (Cooley et al, Blood 110:578 2007). The combination of inhibitory signal blockade with other activators such as low dose IL-2 or mAb capable of ADCC may be needed to best exploit the clinical therapeutic potential of NK cells.

Effect of Sildenafil Citrate (Viagra) on Coronary Flow in Normal Subjects

The purpose of this study was to evaluate the effect of sildenafil citrate (Viagra) on coronary function in normal subjects. The study assessed mean blood pressure, left anterior descending coronary artery (LAD) flow, and echocardiographic variables before and 30 and 60 minutes after taking 50 mg of sildenafil citrate. The mean velocity of LAD flow was assessed with Doppler flow imaging. The study subjects were 6 healthy male volunteers (mean age 37 years). The mean velocity of LAD flow increased 60 minutes after taking sildenafil citrate, but there were no other changes. Two volunteers felt mild flashing and one had mild headache during the study. Sildenafil citrate caused vasodilatation in a normal coronary artery without systemic pressure drops. These results suggest that the agent itself did not have negative effects on the heart in normal subjects.

Glycemia, Lipidemia and Systolic Left Ventricular Function Evaluated by Myocardial Strain Rate: A Tissue Doppler Echocardiographic Study

Recent studies have indicated that hyperglycemia and insulin resistance are significantly correlated to left ventricular (LV) long-axis function, and it seems that optimized glycemic control is significantly related to improved LV function. The aim of the study was to investigate the relation between glucose metabolism, lipid levels and LV long-axis function in normal subjects. The study population consisted of 20 unselected male patients, free of medication and without history of cardiac disease. The main outcome measures were LV systolic strain rate in the long-axis plane, examined by tissue Doppler echocardiography and fasting values of plasma glucose, insulin, cholesterol and triglycerides. The mean systolic strain rate was found to correlate significantly to age (r 2 = 0.34, p < 0.01), fasting blood glucose levels (r 2 = 0.25, p < 0.01) and low-density lipoprotein (LDL) cholesterol levels (r 2 = 0.38, p < 0.01). however, did not correlate significantly to traditional measures of insulin resistance like truncal body fat, fasting insulin or triglyceride levels. In conclusion, LV systolic function seems significantly related to fasting levels of glucose and LDL cholesterol in normal subjects. (E-mail: holmark@ki.au.dk)

The Effect of Patients Positioning on Oxygen Saturation in the Acute Phase of Ischemic Stroke

Body position is known to influence respiratory function in normal subjects & those with respiratory pathology. Its effect on respiratory function after stroke has received little attention. It's generally thought that stroke morbidity is increased by inappropriate position during early recovery phase. The present study was designed to identify changes in arterial oxygen saturation (SaO2) associated with different four positions of the patient in order to detect proper position which maintain the optimum level of SaO2. Quasiexperiment research design was applied in this study. This study was conducted in stroke intensive care unit of Neurological Department of Assuit University Hospitals. The subjects of this study consist of 60 patients with acute ischemic stroke within 48 hours following mild to moderate and sever stroke. Three tools were included in the study, tool of sociodemographic data, tool of the positions and tool of the Scandinavian stroke scale. The result of the present study revealed that there was statistically significant difference between SaO2 and blood pressure of the patients before and after the positions. It was found also that total mean of SaO2 during right side, supine and semi-setting position was nearly equal and there was statistically significant difference between left position and 3 other positions. So, the study recommended the importance of changing patient's positions which improve ventilation and blood pressure. The importance of the use of positions tested (Rt. side, supine and semi-setting position) in the clinical practice to maintain SaO2 in patients of ischemic stroke.

The Effect of Expiratory Muscle Training on Pulmonary Function in Normal Subjects

The Effect of Expiratory Muscle Training on Pulmonary Function in Normal Subjects

The Effect of Expiratory Muscle Training on Pulmonary Function in Normal Subjects

The objective of the present study was to investigate the effects of expiratory muscle training (EMT) on pulmonary function, including peak cough flow (PCF), by administering EMT at a natural or fast flow rate to healthy volunteers. Subjects comprised 33 healthy volunteers randomly divided into 3 groups: EMT at a natural expiratory flow rate (NFR group); EMT at a fast expiratory flow rate (FFR group); and no EMT (Control group). For the NFR and FFR groups, subjects trained using a device for expiratory muscle training at 30% maximal expiratory muscle pressure (PEmax) for 15 min twice daily, 7 days a week for 4 weeks. Before and after training, PEmax and pulmonary function were measured. For the NFR and FFR groups, PEmax significantly increased but pulmonary function, including PCF, was unchanged. Moreover, no significant correlation was seen between changes in PEmax and changes in pulmonary function parameters in the NFR and FFR groups. In conclusion, natural or fast flow rate EMT increases PEmax, but neither technique improves pulmonary function, including PCF. Thus, velocity-specific muscle strengthening by EMT does not contribute to changes in pulmonary function related to expiratory flow.

Effect of two seating positions on upper limb function in normal subjects

Many upper limb functions are performed in a sitting position. However, if seating is inadequate and poorly designed, back pain and reduced upper limb control may result. This study investigates pelvic posture and performance in an upper limb task. In total, 15 normal healthy volunteers (aged 18–30 years) were seated in posterior and anterior pelvic tilt positions and performed a simple upper limb task. The parameters measured were electromyography of the lumbar paravertebral muscles, time taken to complete the task and the task error rate. The data were analysed by repeated measures analysis of variance (ANOVA) and post-hoc t tests. The results indicate that, when seated in an anterior pelvic tilt position, the error rate decreased (P=0.013) and the electrical activity increased (P=0.008). The time taken to complete the task was not significantly different. Since the error rate decreased when seated in the anterior pelvic tilt position, it might be concluded that this posture facilitated task skill. It is suggested that the increase in electrical activity is related to the increased load on the lumbar muscles in maintaining the posture. This study's generalizability is limited, with small subject numbers and the use of a non-functional task. It is, however, a beginning in addressing the interrelationship between the seated posture and skilled upper limb performance.

Effects of Alpha-Blockers on Ejaculatory Function in Normal Subjects.

Effects of Alpha-Blockers on Ejaculatory Function in Normal Subjects.