>Magister Scientiae - MSc / Background: Patients who suffer from diabetic peripheral neuropathy in the leg experience a greater risk of developing gait deviations due to a decrease in strength of the lower extremities, especially the tibialis anterior and triceps surea muscle groups. Aim: The aim of the study was to determine the effect of an exercise training programme on blood pressure, fasting blood glucose, muscle strength, range of motion, balance and gait pattern deviations in patients with diabetic neuropathies. Methods: A total of fourteen participants, who had been diagnosed with diabetic peripheral neuropathy or nocturnal allodynia in either one or both extremities, were asked to participate in this study. Participants were purposively selected from two private Podiatry practices based on their signs and symptoms of diabetic neuropathy, age, gender and doctor’s clearance to participate in any form of physical activity. Dependent variables included isometric strength of the muscles surrounding the hip, knee and ankle, the range of motion of the ankle in plantarflexion and dorsiflexion using goniometry, an assessment of balance using the stork stand test, and a gait pattern analysis, using the modified Tinetti Gait pattern Assessment Scale. Study design: The study was a single-blinded, pre-test and post-test experimental study design using a quantitative approach. Intervention: The researcher (a registered biokineticist) developed a scientifically-based exercise intervention programme to specifically target the entire kinetic chain, and to reduce fall risks, improve quality of life and to assist in developing a standard protocol for patients with DPN. The intervention programme consisted of a combination of ankle, hip and knee rehabilitation, including gait pattern specific rehabilitation. The intervention took place 2-3 times a week for 45 minutes per session and was divided in four categories: Range of motion exercises, strengthening exercises, balance and proprioception and gait pattern training exercises. Results: The Mann-Whitney and Wilcoxon Sign Rank Tests were used to evaluate the differences in dependent variables from pre- to post-intervention. The level of significance was set at p<0.05. An increase in range of motion only in the left ankle dorsiflexion were observed and an increase in balance time for the left leg were observed in the intervention group after a 10-week follow up assessment. Clinical significance was observed in the intervention group, post-intervention, with a decrease in systolic (-9.09%) and diastolic blood pressure (-13.89%) and a decrease in blood glucose levels (-17.89%), however, an increase in these variables was observed in the control group post-intervention. An increase in plantarflexion, 8% (left) and 8% (right) and dorsiflexion 5.26% (left) and an 11.11% (right) increase in range of motion for both left and right ankles, and balance time for both legs, 200% (left) and 159% (right) was observed in the intervention group post-intervention. Although the muscular strength variables showed a mix of an increase and decrease in strength post-intervention in the intervention group, however a clinically significant decreased amount was observed in the control group post-intervention for the majority of muscular strength variables. Conclusions: Although not many findings of this study are statistically significant, clinical significance were observed with most of the variables of this study. The findings of this study can assist future researchers in the development of exercise interventions for patients who suffers from DPN.

The study dealt with the influence of exercise on the autonomic nervous system (ANS) and with factors that may influence the results. ANS function was measured in 183 young, healthy participants, before and after a twelve week standardised, medium-to-high volume physical training programme, in a controlled environment. The effects of the training programme were assessed on resting ANS functioning, during standing and on the response to an orthostatic challenge. ANS function was assessed by means of heart rate variability (HRV) determination. HRV was quantified by three different analytical techniques, i.e., time domain analysis (RR, STDRR, RMSSD and pNN50), frequency domain analysis (LF,LFnu, HF, HFnu and LF/HF) and Poincaré plot analysis (SD1 and SD2). The influence of technical variations, such as variations in tachogram length and period of recording, as well as the influence of pre-intervention values of physiological variables, such as blood pressure, BMI, VO2 max and ANS functioning, on the response to the exercise intervention, were assessed. Results on the exercise intervention showed: <ul><li> Increased supine, as well as standing, parasympathetic cardiac control as indicated by time domain, frequency domain and Poincaré analyses. </li><li> Decreased sympathetic control in the supine position and increased sympathetic control during rising and standing. </li><li> Increased vagal withdrawal, as well as increased sympathetic control during the first phase of the orthostatic response to rising from the supine position. </li><li> Only an exercise-induced increase in sympathetic control when the orthostatic response was measured as the difference between standing and supine. </li></ul> Results on exercise-induced changes in sympathetic and parasympathetic ANS control differ, depending on posture. It is suggested that the effects of an exercise intervention on sympathetic and parasympathetic ANS control of the heart should be assessed from measurements in the supine, in the standing, and in response to an orthostatic stressor. It is further suggested that information obtained during rising will give additional information on the response of the ANS. This study showed that technical as well as physiological variations may lead to differences in the outcome of HRV studies. Results from the technique evaluation showed that the length and period of tachogram recordings should be standardised, especially during an orthostatic challenge. Starting the recording too late will miss out on the initial response to a change in body position. Longer recording times will represent the mean of HRV values obtained during the orthostatic response and that obtained after stabilisation in the standing position. Investigations into the influence of pre-intervention physiological status on exercise-induced changes showed: <ul><li> Baseline ANS functioning is a significant contributor to variations in the ANS response to an exercise intervention. </li><li> Pre-intervention values for physiological variables, such as blood pressure, BMI and VO2 max do not have a significant influence on the HRV response to exercise in young, healthy individuals of average fitness</li><li> Regression analyses confirm the correlation results, i.e. that baseline ANS function is a significant predictor of the ANS response to exercise. </li><li> However, regression results indicated that the combination of pre-intervention values for LFms2, HFms2, BMI, VO2 max, gender and blood pressure, contributes only between 12.83% and 29.82%, depending on the HRV variable, to the exercise induced changes in the autonomic nervous system. </li></ul> / Thesis (PhD)--University of Pretoria, 2011. / Physiology / unrestricted

Title: Possibilities of monitoring and evaluation of accompanying non-locomotor manifestacions during reflex locomotion according to Vojta Objectives: The aim of study is to determine suitable conditions for measuring and evaluating non-locomotor manifestations. Furthermore, to clarify whether there are changes in the accompanying non-locomotor manifestations during the stimulation of trigger zones from the concept of Vojta's principle. Accompanying non-locomotor manifestations are mainly manifestations of the autonomic nervous system. Measurement of respiratory rate, heart rate and swallowing rate was chosen to evaluate these parameters. Methods: The research was conducted on 7 adult subject for measuring respiratory and heart rate and 12 adult subject for measuring swallowing frequency. These were healthy women aged 18-30. Data were obtained from a CamNtech Actiheard compact ECG sensor and from a video recording. Each proband was first measured for a resting ECG and then measured during activaton of the thoracic trigger zone from the Vojta concept, twice in a row for fifteen minutes. One measurement was performed with the eyes open, the other with the eyes closed, the order was randomized. The obtained data were processed into a video recording and evaluated for each proband separately. It was...

Software engineers and researchers in the field are constantly developing new technologies to manage the complexity of current software systems. There is an increasing need for mechanisms that can deal with dynamics in the systems' environment, goals, and requirements. Self-adaptive software systems are a solution to manage the complexity caused by dynamics or runtime variations. Software reuse is a classical solution to deal with complexity and increase the quality of a system in a systematic and efficient way. Despite the large amount of research on self-adaptation, no systematic study has been found, which surveys and reports the application of reuse methods and techniques for the development of self-adaptive software systems. A systematic analysis of reuse methods and techniques for the development of self-adaptive systems is interesting as it provides useful insights for researchers and practitioners in the self-adaptive area. This study systematically reviews relevant research work published between the years 2000 and 2020 at eight well-known venues on self-adaptation and software engineering. By following the systematic literature review method, 97 studies were reviewed and 40 primary studies identified for addressing the research questions. The main objectives of the review are 1) to collect and analyse the reuse-based methods studied and applied for the design and development of self-adaptive software systems, 2) analyse the challenges in the application of reuse-based methods for the development of self-adaptive software systems. The review shows that most of the analysed studies support reuse with component-based software engineering. The primary studies propose different reuse-based methods to allow faster and simpler development of self-adaptive systems. Furthermore, the analysis shows that the reviewed studies report several challenges related to the configuration process, design, performance and uncertainty in the application of reuse methods for the development of self-adaptive systems.

Software engineers and researchers in the field are constantly developing new technologies to manage the complexity of current software systems. There is an increasing need for mechanisms that can deal with dynamics in the systems’ environment, goals, and requirements. Self-adaptive software systems are a solution to manage the complexity caused by dynamics or runtime variations. Software reuse is a classical solution to deal with complexity and increase the quality of a system in a systematic and efficient way. Despite the large amount of research on self-adaptation, no systematic study has been found, which surveys and reports the application of reuse methods and techniques for the development of self-adaptive software systems. A systematic analysis of reuse methods and techniques for the development of self-adaptive systems is interesting as it provides useful insights for researchers and practitioners in the self-adaptive area. This study systematically reviews relevant research work published between the years 2000 and 2020 at eight well-known venues on self-adaptation and software engineering. By following the systematic litera-ture review method, 97 studies were reviewed and 40 primary studies identi-fied for addressing the research questions. The main objectives of the review are 1) to collect and analyse the reuse-based methods studied and applied for the design and development of self-adaptive software systems, 2) analyse the challenges in the application of reuse-based methods for the development of self-adaptive software systems. The review shows that most of the analysed studies support reuse with component-based software engineering. The pri-mary studies propose different reuse-based methods to allow faster and sim-pler development of self-adaptive systems. Furthermore, the analysis shows that the reviewed studies report several challenges related to the configura-tion process, design, performance and uncertainty in the application of reuse methods for the development of self-adaptive systems.

The neurotrophic factor neurturin is required for normal cholinergic innervation of adult mouse heart and bradycardic responses to vagal stimulation. Our goals were to determine effects of neurturin deletion on development of cardiac chronotropic and dromotropic functions, vagal baroreflex response, and cholinergic nerve density in nodal regions of postnatal mice. Experiments were performed on postnatal C57BL/6 wild-type (WT) and neurturin knockout (KO) mice. Serial electrocardiograms were recorded noninvasively from conscious pups using an ECGenie apparatus. Mice were treated with atenolol to evaluate and block sympathetic effects on heart rate (HR) and phenylephrine (PE) to stimulate the baroreflex. Immunohistochemistry was used to label cholinergic nerves in paraffin sections. WT and KO mice showed similar age-dependent increases in HR and decreases in PR interval between postnatal days (P) 2.5 and 21. Treatment with atenolol reduced HR significantly in WT and KO pups at P7.5. PE caused a reflex bradycardia that was significantly smaller in KO pups. Cholinergic nerve density was significantly less in nodal regions of P7.5 KO mice. We conclude that cholinergic nerves have minimal influence on developmental changes in HR and PR, QRS, and QTc intervals in mouse pups. However, cholinergic nerves mediate reflex bradycardia by 1 week postnatally. Deletion of neurturin impairs cholinergic innervation of the heart and the vagal efferent component of the baroreflex early during postnatal development.

Symptomatic sinus bradycardia, due to either sick sinus syndrome or vagotonia, can be familial, affecting several members of a family. We report an 18-year-old male patient with palpitations and limited exercise capacity who was noted to have severe sinus bradycardia. His resting heart rate was 40/min, with normal PR and corrected QT intervals, and sinus pauses up to 6 seconds during sleep. Exercise treadmill test and pharmacologic autonomic blockade during electrophysiologic studies abolished the bradycardia, suggestive of vagotonia rather than intrinsic sinus node dysfunction. This patient's father and a female cousin had a similar clinical history but associated with syncope and severe sinus bradycardia. The mode of transmission appeared to be autosomal dominant. All three have permanent demand pacemakers implanted and are asymptomatic.

Background - This study tested the hypothesis that β1-adrenoreceptor blockade modulates the angiotensin II (Ang II)-evoked neural release of norepinephrine (NE) and epinephrine (Epi) into the cardiac interstitial fluid (ISF) space in experimentally induced mitral regurgitation (MR) in the dog. Methods and Results - Normal dogs (n=8) were compared with dogs with MR of 2 (n=8) and 4 (n=6) weeks' duration and with dogs with MR treated with β1-receptor blockade (RB; extended-release metoprolol succinate, 100 mg QD; MR+β1-RB) that was started 24 hours after MR induction for 2 (n=6) and 4 weeks (n=8). Left ventricular end-diastolic dimension increased 20% as plasma Ang II levels increased >5-fold in both MR and MR+β1-RB dogs at 2 and 4 weeks. Ang II infusion into the left atrium produced increases in ISF NE and Epi in normal dogs, which were further increased in 2- and 4-week MR dogs but were restored to normal in 4-week MR+β1-RB dogs. Ang II infusion produced 4-fold increases in circulating NE and Epi in 2- and 4-week MR dogs that returned to normal in 4-week+β1-RB dogs. Left ventricular angiotensin-converting enzyme activity and ISF Ang II were increased in 4-week MR dogs but were decreased in 4-week MR+β1-RB dogs. Conclusions - β1-RB decreases renin-angiotensin system sympathostimulation and activation by attenuating the Ang II-mediated NE and Epi release into the cardiac ISF and circulation and by decreasing left ventricular angiotensin-converting enzyme expression in the early phases of volume overload.

Background Myocardial infarction (MI) induces remodeling in stellate ganglion neurons (SGNs). Objective We investigated whether infarct site has any impact on the laterality of morphologic changes or neuropeptide expression in stellate ganglia. Methods Yorkshire pigs underwent left circumflex coronary artery (LCX; n = 6) or right coronary artery (RCA; n = 6) occlusion to create left- and right-sided MI, respectively (control: n = 10). At 5 ± 1 weeks after MI, left and right stellate ganglia (LSG and RSG, respectively) were collected to determine neuronal size, as well as tyrosine hydroxylase (TH) and neuropeptide Y immunoreactivity. Results Compared with control, LCX and RCA MIs increased mean neuronal size in the LSG (451 ± 25 vs 650 ± 34 vs 577 ± 55 μm2, respectively; P =.0012) and RSG (433 ± 22 vs 646 ± 42 vs 530 ± 41 μm2, respectively; P =.002). TH immunoreactivity was present in the majority of SGNs. Both LCX and RCA MIs were associated with significant decreases in the percentage of TH-negative SGNs, from 2.58% ± 0.2% in controls to 1.26% ± 0.3% and 0.7% ± 0.3% in animals with LCX and RCA MI, respectively, for LSG (P =.001) and from 3.02% ± 0.4% in controls to 1.36% ± 0.3% and 0.68% ± 0.2% in LCX and RCA MI, respectively, for RSG (P =.002). Both TH-negative and TH-positive neurons increased in size after LCX and RCA MI. Neuropeptide Y immunoreactivity was also increased significantly by LCX and RCA MI in both ganglia. Conclusion Left- and right-sided MIs equally induced morphologic and neurochemical changes in LSG and RSG neurons, independent of infarct site. These data indicate that afferent signals transduced after MI result in bilateral changes and provide a rationale for bilateral interventions targeting the sympathetic chain for arrhythmia modulation.

Using vagus nerve stimulation (VNS), we sought to determine the contribution of vagal afferents to efferent control of cardiac function. In anesthetized dogs, the right and left cervical vagosympathetic trunks were stimulated in the intact state, following ipsilateral or contralateral vagus nerve transection (VNTx), and then following bilateral VNTx. Stimulations were performed at currents from 0.25 to 4.0 mA, frequencies from 2 to 30 Hz, and a 500-μs pulse width. Right or left VNS evoked significantly greater current-and frequency-dependent suppression of chronotropic, inotropic, and lusitropic function subsequent to sequential VNTx. Bradycardia threshold was defined as the current first required for a 5% decrease in heart rate. The threshold for the right vs. left vagus-induced bradycardia in the intact state (2.91 ± 0.18 and 3.47 ± 0.20 mA, respectively) decreased significantly with right VNTx (1.69 ± 0.17 mA for right and 3.04 ± 0.27 mA for left) and decreased further following bilateral VNTx (1.29 ± 0.16 mA for right and 1.74 ± 0.19 mA for left). Similar effects were observed following left VNTx. The thresholds for afferent-mediated effects on cardiac parameters were 0.62 ± 0.04 and 0.65 ± 0.06 mA with right and left VNS, respectively, and were reflected primarily as augmentation. Afferent-mediated tachycardias were maintained following β-blockade but were eliminated by VNTx. The increased effectiveness and decrease in bradycardia threshold with sequential VNTx suggest that 1) vagal afferents inhibit centrally mediated parasympathetic efferent outflow and 2) the ipsilateral and contralateral vagi exert a substantial buffering capacity. The intact threshold reflects the interaction between multiple levels of the cardiac neural hierarchy.