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The significance of the difference between the group mean scores in each item was determined using Fisher’s t statistic at the 5 per cent level of confidence. The results indicate that the Control group improved significantly in all the Vitalometer items in amounts similar to the mean improvements of the exercise groups. It was concluded that influences other than training effects were responsible for the changes in the Vitalometer test scores. The variables therefore, were of no further interest for this study. The Bonne Santé group evidenced significant improvements in the Heartometer Resting Pulse Rate (this improvement, however, was based on data which appeared to be unreliable and thus suspect)', the Area Under The Curve-Sitting, the Sitting and Standing Systolic Amplitudes, the Two Minute Recovery Pulse Count Post 24 Steps Per Minute. The Rhythmic Gym group showed significant improvements in the Area Under The Curve-Sitting, and the Sitting Systolic Amplitude. The separate training regimens followed by each of the experimental groups were considered to be of insufficient frequency and intensity to produce uniform and physiologically important improvements in the cardiovascular and respiratory fitness levels of the subjects. The Bonne Santé group showed greater relative improvement in fitness partly because the members tended to be less fit initially than the subjects in the Rhythmic Gym group, and partly because they spent more hours in exercise each week. / Education, Faculty of / Curriculum and Pedagogy (EDCP), Department of / Graduate

The purpose of this study was to investigate the changes in cardiovascular dynamics as depicted by systolic time intervals, blood pressure and heart rate during a 50% MVC and 100% MVC isometric contraction of the forearm in a control and heated environment. Fourteen normal male volunteers aged 20 to 31 were used as subjects. Simultaneous recordings of the phonocardiogram, electrocardiogram, carotid pulse wave and blood pressure were conducted for each subject at rest and during exercise in a seated position. Subjects were tested, in room temperature and in a sauna where the skin temperature was raised to 40°C -41°C. Testing took place on two separate days with one day of rest in between. Half of the subjects experienced the heated conditions first, while the other half was tested in room conditions first. The results from two of the subjects were discarded because of poor quality reproduction of the time interval recordings. For each recording only the three clearest cycles closest to the termination of the contraction period were used for statistical analysis. The data were treated with a two-way ANOVA for each dependent variable. In some cases a post-hoc analysis (Newman-Keuls method) was used to determine specific differences between workload or environment effects. The fourteen dependent variables studied were divided into the following groups: a) Systole related variables left ventricular ejection time (LVET) mechanical systole (MS) total systole (TS) ejection time index (ETI) Diastole related variables cycle time (CT) diastole (DIAS) Sympathoadrenergic Activity (Contractility) pre-ejection period (PEP) isovolumetric contraction period (ICP) PEP/LVET (ratio) Afterload systolic blood pressure (BPs) diastolic blood pressure (BPd) Electromechanical Lag (EML) Heart Rate (HR) Myocardial Oxygen Consumption (Index) triple product (TRIP) -CONCLUSIONS The oxygen consumption of the myocardium as depicted by the triple product significantly increased during submaximal and maximal isometric handgrip contraction. This increase was evident at room temperature and during body heating. There was no significant change in the myocardial oxygen consumption as depicted by TRIP at rest or during isometric forearm contraction between the control and heated environments. This suggests that the heat stress did not significantly increase the myocardial oxygen requirements. 3. In a state of rest, increasing the skin temperature to between 40°C -41°C did not significantly alter either BPs or BPd when compared to a resting state at room temperature. However, BPs and BPd were substantially lower during isometric work in the heat than during isometric work at room temperature. 4. BPs and BPd significantly increased during 50% MVC and 100% MVC static contractions of the forearm. This increase was demonstrated in both environmental conditions. 5. All variables depicting changes in left ventricular systole (LVET; MS; TS) and ventricular diastole (diastole and CT) were found to become significantly reduced with submaximal and maximal static contractions of the forearm. These changes were evident in both environments. 6. A strong inverse correlation was found between HR and LVET, CT and diastole. HR significantly increased from rest to 100% MVC in both environmental conditions. Consequently, it is suggested that alterations in LVET, CT and diastole are largely determined by the rate of myocardial contraction. 7. The ejection time index significantly increased in both environmental conditions with a 50% MVC and 100% MVC static contraction of the forearm. The electromechanical lag showed a general tendency to decrease during an isometric handgrip contraction. However, subsequent post-hoc analysis (Newman-Keuls) demonstrated that EML did not significantly decrease during a submaximal or maximal isometric contraction of the forearm. It is suggested that care be taken to choose a proper statistical procedure for analysis of EML. The contractility of the heart as depicted by changes in LCP, PEP and PEP/LVET increases in response to a pressure load produced by static exertion but is not significantly altered by an augmented volume load associated with heat stress. HR, LVET, MS, TS, PEP, ICP, PEP/LVET and EML changed in an additive fashion from rest to 100% MVC during subjection to a volume load and pressure load simultaneously. In contrast alterations in BPs, BPd, ETI, CT, diastole, and TRIP displayed interactive characteristics during the same test conditions . / Education, Faculty of / Curriculum and Pedagogy (EDCP), Department of / Graduate

Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

lschemic disease in form of ischemic heart disease (IHD), ischemic stroke and peripheral arterial disease (PAD) due to atherosclerosis represents a massive clinical and economic burden to healthcare and is currently the number one cause of death in the world. Treatment modalities for peripheral arterial disease include bypass surgery involving autologous vein or synthetic materials such as ePTFE. Long term patency of small diameter vascular grafts used for infra-inguinal reconstructions, however, is below 50 % 5 years after implantation. Therefore, novel vascular graft concepts and materials are needed. The concept of transmural in vivo endothelialisation of vascular grafts holds great promise for increasing long term patency. To achieve complete luminal endothelial cell coverage and optimal integration of the porous synthetic graft material into the host tissue, transmural ingrowth of tissue and vasa vasorum might have to be facilitated. Since VEGF1ss and PDGF-BB are growth factors known to stimulate and consolidate angiogenesis, this PhD thesis hypothesized, that neovascularisation of porous polyurethane (PU) can be increased by delivery of vascular endothelial growth factor (VEGF1ss) and platelet derived growth factor (PDGF-BB). To prove this hypothesis, subcutaneous implantation of PU discs was established as a valid, reproducible, relatively simple and quantifiable neovascularisation model. Three different ways of growth factor delivery were investigated. The gene encoding for human VEGF15s was cloned into the genome of adeno associated viruses (AAV), which served as a vector for gene transduction of autologous wound healing cells in vivo using the "Gene Activated Matrix" approach. Genetically modified matrix embedded AAV-VEGF155 was loaded into porous PU and transduced autologous ingrowing wound cells. In contrast to the excellent transduction efficiency in myocytes, AA V showed a poor tropism for wound healing cells. The second approach to increase neovascularisation into porous PU was the surface modification of PU by covalent attachment of nitrous acid degraded heparin. Neovascularisation into the biomaterial was increased by 77 % after 10 days of subcutaneous implantation. Since certain angiogenic growth factors show a high affinity for heparin, additional loading of heparin surface modified PU with VEGF165 increased neovascularisation even further up to 115 % at 10 days compared to control. Dual growth factor delivery of VEGF 165 and PDGF-BB not only initiated increased vascularisation of porous PU, but also created a stable vascular network 2 months after implantation. In contrast, PU loaded with VEGF165 alone showed regression of total vascular area of 61 % compared to vascular area at 10 days. Thirdly, to study the effects of controlled, prolonged growth factor delivery, a "Neovascularisation Construct" was developed which was implanted subcutaneously in rats. The construct consisted of an osmotic mini pump and a tube of porous PU lined with ePTFE, into which a defined amount of VEGF16s was pumped for 10 days. After implantation, granulation tissue was growing into the pores of the PU and neovascular area was increased up to 265 % compared to PBS control. Furthermore, using different growth factor concentration, a dose dependency was shown. In addition, this thesis investigated the functional perfusion of the micro vascular network growing into PU by four different vascular quantification techniques. lntravital perfusion with biotinylated lycopersicon esculentum followed by microscopical analysis, vascular corrosion casting quantified by scanning electron microscopy as well as the novel micro-CT analysis of silicone rubber perfused vessels were compared to conventional immunhistochemical analysis of endothelial cells by CD31. Interestingly, PBS perfused "Neovascularisation Constructs" showed a relatively poor perfusion; therefore CD31 immunohistochemistry "overestimated" functional neovascularisation 3 fold. All perfusion techniques indicated a strong effect of VEGF 165 delivery on vessel perfusion (10 to 20 fold increases of vascular area and volume compared to PBS control). Micro-CT scanning was shown to be an excellent tool to study micro vascular networks in a three-dimensional fashion across the whole length of the sample in a limited amount of time and to provide reliable and reproducible data on vessel density, vascular volume, and connectivity. Since resolution is still limited today to about 10 μm using a commercially available bench top scanner, this new technology still needs to be complemented by immunohistochemistry and perfusion studies such as lectin perfusion and corrosion casting. In summary, the induction of neovascularisation was achieved by heparin surface modification alone, which was even increased through additional delivery of growth factors into the biomaterial PU. The development of a stable micro vascular network at 2 months was achieved and the functionality was shown using four different, independent techniques including the novel micro-CT scanning of neovascularisation into biomaterials. Towards the development of an in vivo, spontaneously and transmurally endothelialising vascular graft with superior long-term patency further investigations are necessary. As an initial step, increased spontaneous neovascularisation of the possible graft material polyurethane was achieved. Future steps are clearly indicated to study the translation of increased neovascularisation of the biomaterial polyurethane towards increased endothelialisation in a vascular graft model.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.