O oxigênio atua como substrato ou cofator numa série de reações bioquímicas do metabolismo primário e secundário das plantas. Várias estratégias têm sido utilizadas no sentido de interferir neste metabolismo aeróbico, visando, entre outras possibilidades, reduzir a formação de espécies reativas de oxigênio (ROS). A fim de alterar a disponibilidade de oxigênio no interior da organela, foram produzidas plantas de fumo (Nicotiana tabacum) expressando a leghemoglobina de soja no interior das mitocôndrias. Para tanto, as plantas foram transformadas, via Agrobacterium tumefaciens, com uma construção quimérica, onde o gene da Lba de soja foi fusionado a uma seqüência de direcionamento mitocondrial. A expressão do gene quimérico foi assegurada pela presença do promotor constitutivo 35S, do vírus do mosaico da couve-flor. A proteína foi corretamente importada e processada no interior das mitocôndrias. Entretanto, não foi possível detectar alterações significativas na função mitocondrial. Numa segunda etapa do presente trabalho, plantas transgênicas de batata (Solanum tuberosum cv Bintje) expressando a leghemoglobina de soja no interior dos cloroplastos, foram caracterizadas do ponto de vista molecular e fenotípico. Observou-se que as plantas apresentaram um fenótipo semelhante àquelas deficientes na biossíntese de giberelina / not available

Bakgrund: Larvterapi är en alternativ behandlingsmetod i bensårsläkning. Sårläkning med larver har förekommit i mer än 70 år men vid antibiotikans introduktion minskades användandet av larvterapi. Då det idag finns problem med antibiotikaresistens introducerades larvterapi åter. Syftet med denna studie var att belysa hur larvterapi påverkar bensårsbehandlingen för patienter med kroniska bensår. Metod: En integrativ litteraturstudie genomfördes utifrån två kvalitativa och sju kvantitativa vetenskapliga artiklar.  Resultat: Det som belystes var fysiologisk påverkan av bensåret såsom debridering och läkning samt upplevelsen av larvterapi såsom smärta, obehagskänslor och lukt. Studien visade att debridering vid bensår med larvterapi gav bättre resultat än med hydrogelbehandling. Larverna debriderade såren från nekrotisk vävnad så att bensårens omfång minskade drastiskt. Anmärkningsvärt var att sex av nio studier nämnde att smärta upplevdes under behandlingsprocessen men att acceptansen av larvterapi som behandlingsform var över förväntan trots smärtan. En del patienter hade initialt en negativ inställning inför larvterapi men var villiga att prova behandlingsmetoden. Larvterapi kunde förbättra patienters välbefinnande och vid smärtförekomst gick behandlingsmetoden att genomföra med hjälp av information och smärtstillande läkemedel varvid den totala läkningstiden förkortades. / Background: Larval therapy is an alternative treatment method in wound healing. Wound healing with larvae has occurred for more than 70 years. The introduction of antibiotics decreased larval therapy, but though there are problems with the resistance of antibiotics, larval therapy returned. The objective of this study was to highlight the impact of larval therapy for chronic leg ulcers.  Method: An integrative literature study was performed based on two qualitative and seven quantitative scientific articles.  Results: The impacts of the leg ulcers that were highlighted were physiological such as debridement and healing, also the experience of larval therapy such as pain, feelings of discomfort and wound odor. The study showed that the debridement in leg ulcers with larval therapy gave better results than hydrogel treatment. The larvae debrided necrotic tissue from the wounds and decreased the wound dramatically. Remarkably, six out of nine studies mentioned pain as a big factor during treatment but the acceptance of larval therapy was beyond expectation. Although some patients were reluctant to try larval therapy, most patients were willing to go through with the treatment. Larval therapy improved the wellbeing of patients and if pain occurred during larval therapy patients were motivated with information and were relieved with painkillers so the total time of healing was shortened.

Whole Body Vibration (WBV) training is a new addition to the field of Exercise and Sports Science and has been developed for the use in strength and conditioning exercises. With the introduction of this new mode of exercise, the study focused on comparing the strength gaining effect of WBV training versus conventional resistance training. The study was conducted in a descriptive, exploratory manner utilizing a quasi-experimental approach with a three group comparison pre-test-post-test design consisting of an experimental-, comparison- and control group. Convenience and snowball sampling were used to select 43 male and female healthy, sedentary volunteer participants. The research focused on reviewing the contribution that each mode of training offers to increase strength in the upper leg and underlines the important physiological adaptations that the human body undergoes to bring about an increase in muscle strength. Both the whole body vibration and land-based resistance groups trained three times a week over an eight week intervention period. Exercises were performed with progressive increments in the frequency, amplitude and duration for the WBV- and in workload, number of sets and repetitions for the conventional resistance training program. The control group remained sedentary throughout the duration of the study. The dependent variables of peak torque flexion and extension of the knee joint in both legs were analyzed using descriptive and inferential statistics. Analysis of covariance (ANCOVA) was done to determine intra-group differences. Post-hoc analysis in the form of Scheffé’s test was done to determine and compare inter-group differences. Practical significance was indicated by means of Partial eta2 The analysis of the results revealed significant strength increases in both conventional resistance training and WBV for most of the dependent variables, except for peak torque extension, where the WBV group did not increase significantly. Based on these results, it can be concluded that both modes of conventional resistance and whole body vibration increased selected dependent variables for upper leg strength in previously inactive individuals.

A PC based waveform acquisition and analysis system has been developed for use in aorta-iliac arterial assessment. A Motorola DSP56001 based system containing dual Analog to Digital converters is used to sample phase quadrature demodulated signals from a commercially available continuous wave Doppler unit. The Power Spectral Density is calculated using an autoregressive model from which the mean velocity waveform is calculated. This waveform is used to calculate the damping factor, vessel compliance and runoff resistance of a simple electrical model of the lower limb arterial circulation using a non-linear regression technique of curve fitting in the time domain. A pilot study using the system shows a significant separation (p < 0.001 Mann Whitney U-test) between the damping factors of a normal control group (quartile range = 0. 15 - 0.25 ; median = 0. 19) and a patient group with angiographically determined aorta-iliac arterial disease (quartile range = 0.45 - 0.89 ; median= 0.49).

Thesis: B.S., Massachusetts Institute of Technology, Department of Biology, 1977 / by Gene Paul Masters. / B.S. / B.S. Massachusetts Institute of Technology, Department of Biology

No description available.

The foot/ankle complex (particularly the hindfoot) is frequently injured in a wide array of debilitating events, such as car crashes. Numerical models have been used to assess injury risk, but most are minimally validated and do not account for variations in ankle posture that frequently occur during these events. The purpose of this study was to develop an accurate finite element (FE) model of the foot and ankle that accounts for these positional changes. The bone positions and load path in the foot and ankle were quantified throughout its natural range of motion. CT scans were taken of a male cadaveric leg in five postures in which fractures are commonly reported, while strains were recorded by strain gauges attached to the hindfoot bones in response to quasi-static, sub-failure loading. Substantial variations in bone displacements, rotations and strains were observed for all postures tested, highlighting the need for an FE model that accounts for these positional changes. The CT scans were used as the basis of an FE model of the foot and ankle that was developed using TrueGrid® and LS-Dyna® software. The model met rigorous mesh quality criteria, and its properties were optimized to best represent the experimental plantar tissue compression and surface strains. The model was evaluated by comparing its bone position and strain responses to the experimental results in each posture. The fracture thresholds and locations in each posture were estimated and were similar to those reported in the literature. The least vulnerable posture was neutral, and the talus and calcaneus exhibited the lowest fracture thresholds in all postures. This work will be useful in developing improved injury limits for the ankle and postural guidelines to minimize injury. The model can be used to evaluate new protective systems to reduce the occurrence of lower leg injuries. / Thesis / Master of Applied Science (MASc) / Ankle fractures are common occurrences that can lead to severe disability. Safety evaluations of the lower leg are often performed using computer models in a neutral ankle posture, which may underestimate the fracture tolerance in altered postures. The purpose of this study was to develop a computer model of the ankle that accounts for these changes. A cadaveric leg was used to determine how the locations of and strains in the bones of the foot and ankle varied as ankle posture was adjusted. A computer model of the lower leg and ankle was developed, and its accuracy was evaluated by comparison with the experimental results. The least vulnerable posture was neutral, and the hindfoot bones were the most likely to experience fracture in all postures. This model can be used in the future to evaluate new protective systems and develop comprehensive injury criteria for these altered postures.

No description available.

No description available.

No description available.