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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Consistency of near-infrared spectroscopy chromophores during a 10-minute vascular occlusion procedure of the thigh over 5 consecutive days

Mackintosh, Cameron Eve 07 July 2016 (has links)
The purpose of this study was to examine the consistency of near-infrared spectroscopy (NIRS) measures associated with a 10 minute vascular occlusion of the thigh during 5 consecutive days. A secondary purpose was to examine if the repeated daily occlusions modify the vascular response to such occlusions. The NIRS chromophores of oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (HHb), total hemoglobin (tHb), hemoglobin difference (HbDiff), and total saturation index (TSI) were monitored at the vastus lateralis muscle during each testing session. Participants were female (age 18-30 yrs) and were randomly assigned to one of two groups. The Test Group (age 23 ± 2yrs) completed an occlusion test every day for 5 consecutive days while the Control Group (age 21 ±1.6yrs) was tested on days 1, 3 and 5. Each testing session involved 10 minutes rest in a supine position, 10 minutes of femoral artery occlusion (preset at 250mmHg), 10 minutes of recovery. At onset of occlusion, the rapid cuff inflation system inflated in 0.3 seconds to the preset 250mmHg. Following the 10 minutes of occlusion, the cuff was deflated in 0.3 seconds. Heart rate was monitored throughout all testing sessions and mean arterial pressure was calculated and compared between groups. There were no significant group or day main effects found, nor any significant interactions for the following hemoglobin chromophores measures: HbO2, HHb, HbDiff, and TSI. In all participants, the NIRS response pattern to rest, occlusion and recovery was consistent for all testing days regardless of group. The response pattern to the occlusion initiated by the rapid cuff inflation was as follows: HbO2, tHb, HbDiff, and TSI decreased then slowly plateaued over the 10 minutes while HHb increased initially and then plateaued. Following the rapid cuff deflation, HbO2, tHb, HbDiff and TSI increased to their maximum reperfusion levels and then plateaued over the remainder of the 10 minutes of recovery. During that same period, HHb decreased initially upon reperfusion and then plateaued. Unlike the other measures, TSI and tHb demonstrated inconsistencies in their response pattern regardless of group or day. The consistency of hemoglobin chromophores response pattern to daily 10 minute vascular leg occlusions over 5 consecutive days is an important finding of this study. This response indicates that there is no apparent change in vascular response to repeated occlusions and has implications for exercise studies that use occlusion in their methodology. The study also emphasizes the inconsistency of tHb and TSI as primary hemoglobin response measures to occlusion. Similarly, the results demonstrate the potential misinterpretation of results if only relying on one hemoglobin measure during occlusion. / Graduate
2

Efekt silového cvičení s vaskulární okluzí na sílu flexorů předloktí / Effect of strength training with vascular occlusion on the forearm flexors muscle strength

Rysová, Jana January 2015 (has links)
Title: Effect of strength training with vascular occlusion on the forearm flexor muscle strength. Aims: The aim is to determine the effect of vascular occlusion on maximum isometric strength of forearm muscles. Methodology: The research group of 8 volunteers underwent six weeks of exercise program for upper limb (UL). The exercise program was different for each upper limb. Probands practiced one UL with vascular occlusion and second one without vascular occlusion. The research group was measured maximal isometric strength of forearm muscles before the 6-week exercise block, after 3 weeks of training and after completion of the cycle. All measurements were carried out in the laboratory climbing walls FTVS UK. The results were statistically evaluated using test ANOVA with repeated measurement. Results: The results of examining the impact of vascular occlusion to increase muscle strength flexor forearm in this thesis confirmed. Testing did not find significant differences in absolute strength or relative strength between exercise with vascular occlusion and exercise without vascular occlusion. Absolute strength at exercise with vascular occlusion averaged before exercise program 422 N, after the completion of 461 N. Absolute strength at exercise without vascular occlusion averaged before exercise...
3

Efeitos do treinamento de força de baixa intensidade associado à restrição parcial do fluxo sanguíneo na força, hipertrofia e modulação das células satélites musculares em idosos / Effects of low load resistance training with partial blood flow restriction in the strength and hypertrophy gains as well as in the muscle satellite cells content in elderly

Vechin, Felipe Cassaro 15 December 2014 (has links)
O treinamento de força de baixa intensidade com restrição parcial do fluxo sanguíneo (TFR) emergiu como uma alternativa ao treinamento de força tradicional, com intensidades variando entre moderada a alta, principalmente para idosos que possam apresentar alguma limitação ou dificuldade na realização do treinamento mais intenso. Assim, o presente estudo objetivou analisar a efetividade do TFR na modulação dos níveis de força, área de secção transversa muscular (ASTM) e dos diferentes tipos de fibra (ASTF) bem como da quantidade de células satélites (CS) e mionúcleos (MIO) presentes nas células musculares de indivíduos idosos e comparar os ganhos proporcionados por esse treinamento com os ganhos do treinamento de força tradicional. Trinta sujeitos foram alocados de maneira aleatória e balanceada, pela área de secção transversa muscular do quadríceps, nos seguintes grupos: grupo controle (GC), treinamento de força de baixa intensidade com restrição parcial do fluxo sanguíneo (TFR) e treinamento de força de alta intensidade (TFAI). Após 12 semanas de treinamento, realizados duas vezes na semana, com o exercício Leg Press ambos os grupos, TFR e TFAI apresentaram aumentos nos níveis de força muscular (17% P = 0,067 e 54% P < 0,001 respectivamente) e na ASTM do quadríceps (P < 0,001; 6,6% e 7,9% respectivamente). O grupo controle não apresentou nenhuma alteração significativa dessas variáveis. Após o período de intervenção, a ASTF bem como a quantidade de CS e MIO presentes nas fibras musculares não apresentaram alterações estatisticamente significantes para nenhum dos grupos. Entretanto, no grupo controle foi observada uma queda na ASTF (tipo I = -10%; tipo II = -1%) e também na quantidade de CS e MIO presentes nas fibras (CS = -29,2%; MIO = -9,7%). Para o grupo TFR foi observado um aumento na ASTF tipo II de 13%, contudo um decréscimo de 6% na ASTF do tipo I. Na quantidade de CS o grupo TFR apresentou uma queda de 5% enquanto que para quantidade de MIO foi apresentado um acréscimo de 14,6%. Já o grupo TFAI apresentou uma elevação de 15% na ASTF para ambos os tipos de fibra, I e II. A quantidade de CS aumentou em 32,6% enquanto que a quantidade de MIO presente nas fibras musculares aumentou 3,6%. Os achados do presente estudo mostram adaptações similares nos ganhos de força e hipertrofia muscular entre o TFR e o TFAI, sendo ambos efetivos em reverter os efeitos deletérios do envelhecimento nessas variáveis, consolidando assim o TFR como uma possível alternativa ao TFAI. Quanto à modulação da ASTF bem como da quantidade de CS e MIO por fibra muscular, se comparado ao controle, que apresentou queda nos níveis dessas variáveis, ambos os treinos TFR e TFAI foram capazes de retardar o efeito do envelhecimento sobre essas variáveis, sendo o TFAI mais efetivo em modular a ASTF do tipo I e a quantidade de CS por fibra em dozes semanas de treinamento, realizados duas vezes na semana. Já para modulação da quantidade de MIO por fibra, o TFR apresentou uma ligeira vantagem frente ao TFAI. Dessa forma, em nível celular, no que diz respeito à ASTF, CS e MIO ambos os treinos, após 12 semanas com uma frequência de treinamento baixa, parecem capazes de preservar os níveis dessas variáveis frente ao processo de envelhecimento / The low load resistance training with blood flow restriction (BFR) emerged as an alternative training mode to traditional resistance training (RT), with moderate to high intensities, mainly to elderly, with some limitations or losses, unable to exercise the traditional RT. Thus, the aim of the present study was comparing the effectiveness of BFR to promote strength gains, increases in the muscle and fibers cross sectional area (CSAm and CSAf in that order) as well as an augment in the muscle satellite cells (SC) and myonucleous (MYO) contents in elderly with RT results in these variables. Thirty elderly individuals were ranked in quartiles according to their initial quadriceps CSA and then randomly allocated into one of the following groups: control (CG), low-intensity resistance training with blood flow restriction group (BFR) and high-intensity resistance training (HRT). After 12 weeks of training, twice a week, using the Leg Press exercise, both groups, BFR and HRT presented increases to muscle strength (17% P = 0,067 e 54% P < 0,001 respectively) and CSAm (P < 0,001; 6,6% e 7,9% respectively). The CG did not present any significantly alteration in these variables. After the intervention, the CSAf as well as the SC and MYO contents did not show any significantly alteration for the three groups. However in the CG was observed a CSAf decreases (type I = -16%; type II = -12%) even as in the SC and MYO (CS= -29,2; MYO = -9,7%). To the BFR group was observed an increase of 13% in the type II CSAf while type I presented a decrease of 6%. The CS content decreases 5% whereas MYO content show a increase of 14,6%. To the HRT, both fibers type, I and II, presented an increase in the CSAf (type I = 1%; type II = 12%). To CS and MYO contents HRT showed an augment of 32,6% and 3,6 % respectively. These finds indicate similar strength and hypertrophy gains between BFR and HRT, being both training capable to offset age-related loss in muscle strength and mass, placing the BFR as a surrogate approach to HRT. Comparing the CSAf as well as SC and MYO modulation after intervention in both groups with the control group, BFR and HRT seems capable to break the aging impact on these variables, being the HRT slightly more effective to increase the type I CSA and CS contents while BFR seems slight more effective to increase MYO contents after 12 weeks of training twice a week. On this way both training, BFR and HRT, showed able to preserve CSAf levels even as CS and MYO content during aging
4

Efeitos do treinamento de força de baixa intensidade associado à restrição parcial do fluxo sanguíneo na força, hipertrofia e modulação das células satélites musculares em idosos / Effects of low load resistance training with partial blood flow restriction in the strength and hypertrophy gains as well as in the muscle satellite cells content in elderly

Felipe Cassaro Vechin 15 December 2014 (has links)
O treinamento de força de baixa intensidade com restrição parcial do fluxo sanguíneo (TFR) emergiu como uma alternativa ao treinamento de força tradicional, com intensidades variando entre moderada a alta, principalmente para idosos que possam apresentar alguma limitação ou dificuldade na realização do treinamento mais intenso. Assim, o presente estudo objetivou analisar a efetividade do TFR na modulação dos níveis de força, área de secção transversa muscular (ASTM) e dos diferentes tipos de fibra (ASTF) bem como da quantidade de células satélites (CS) e mionúcleos (MIO) presentes nas células musculares de indivíduos idosos e comparar os ganhos proporcionados por esse treinamento com os ganhos do treinamento de força tradicional. Trinta sujeitos foram alocados de maneira aleatória e balanceada, pela área de secção transversa muscular do quadríceps, nos seguintes grupos: grupo controle (GC), treinamento de força de baixa intensidade com restrição parcial do fluxo sanguíneo (TFR) e treinamento de força de alta intensidade (TFAI). Após 12 semanas de treinamento, realizados duas vezes na semana, com o exercício Leg Press ambos os grupos, TFR e TFAI apresentaram aumentos nos níveis de força muscular (17% P = 0,067 e 54% P < 0,001 respectivamente) e na ASTM do quadríceps (P < 0,001; 6,6% e 7,9% respectivamente). O grupo controle não apresentou nenhuma alteração significativa dessas variáveis. Após o período de intervenção, a ASTF bem como a quantidade de CS e MIO presentes nas fibras musculares não apresentaram alterações estatisticamente significantes para nenhum dos grupos. Entretanto, no grupo controle foi observada uma queda na ASTF (tipo I = -10%; tipo II = -1%) e também na quantidade de CS e MIO presentes nas fibras (CS = -29,2%; MIO = -9,7%). Para o grupo TFR foi observado um aumento na ASTF tipo II de 13%, contudo um decréscimo de 6% na ASTF do tipo I. Na quantidade de CS o grupo TFR apresentou uma queda de 5% enquanto que para quantidade de MIO foi apresentado um acréscimo de 14,6%. Já o grupo TFAI apresentou uma elevação de 15% na ASTF para ambos os tipos de fibra, I e II. A quantidade de CS aumentou em 32,6% enquanto que a quantidade de MIO presente nas fibras musculares aumentou 3,6%. Os achados do presente estudo mostram adaptações similares nos ganhos de força e hipertrofia muscular entre o TFR e o TFAI, sendo ambos efetivos em reverter os efeitos deletérios do envelhecimento nessas variáveis, consolidando assim o TFR como uma possível alternativa ao TFAI. Quanto à modulação da ASTF bem como da quantidade de CS e MIO por fibra muscular, se comparado ao controle, que apresentou queda nos níveis dessas variáveis, ambos os treinos TFR e TFAI foram capazes de retardar o efeito do envelhecimento sobre essas variáveis, sendo o TFAI mais efetivo em modular a ASTF do tipo I e a quantidade de CS por fibra em dozes semanas de treinamento, realizados duas vezes na semana. Já para modulação da quantidade de MIO por fibra, o TFR apresentou uma ligeira vantagem frente ao TFAI. Dessa forma, em nível celular, no que diz respeito à ASTF, CS e MIO ambos os treinos, após 12 semanas com uma frequência de treinamento baixa, parecem capazes de preservar os níveis dessas variáveis frente ao processo de envelhecimento / The low load resistance training with blood flow restriction (BFR) emerged as an alternative training mode to traditional resistance training (RT), with moderate to high intensities, mainly to elderly, with some limitations or losses, unable to exercise the traditional RT. Thus, the aim of the present study was comparing the effectiveness of BFR to promote strength gains, increases in the muscle and fibers cross sectional area (CSAm and CSAf in that order) as well as an augment in the muscle satellite cells (SC) and myonucleous (MYO) contents in elderly with RT results in these variables. Thirty elderly individuals were ranked in quartiles according to their initial quadriceps CSA and then randomly allocated into one of the following groups: control (CG), low-intensity resistance training with blood flow restriction group (BFR) and high-intensity resistance training (HRT). After 12 weeks of training, twice a week, using the Leg Press exercise, both groups, BFR and HRT presented increases to muscle strength (17% P = 0,067 e 54% P < 0,001 respectively) and CSAm (P < 0,001; 6,6% e 7,9% respectively). The CG did not present any significantly alteration in these variables. After the intervention, the CSAf as well as the SC and MYO contents did not show any significantly alteration for the three groups. However in the CG was observed a CSAf decreases (type I = -16%; type II = -12%) even as in the SC and MYO (CS= -29,2; MYO = -9,7%). To the BFR group was observed an increase of 13% in the type II CSAf while type I presented a decrease of 6%. The CS content decreases 5% whereas MYO content show a increase of 14,6%. To the HRT, both fibers type, I and II, presented an increase in the CSAf (type I = 1%; type II = 12%). To CS and MYO contents HRT showed an augment of 32,6% and 3,6 % respectively. These finds indicate similar strength and hypertrophy gains between BFR and HRT, being both training capable to offset age-related loss in muscle strength and mass, placing the BFR as a surrogate approach to HRT. Comparing the CSAf as well as SC and MYO modulation after intervention in both groups with the control group, BFR and HRT seems capable to break the aging impact on these variables, being the HRT slightly more effective to increase the type I CSA and CS contents while BFR seems slight more effective to increase MYO contents after 12 weeks of training twice a week. On this way both training, BFR and HRT, showed able to preserve CSAf levels even as CS and MYO content during aging
5

Retinal vascular blood flow in patients with retinal vein occlusions

Koch, Rachelle Elif 10 July 2020 (has links)
PURPOSE: This study aims to quantify the retinal vascular blood flow in eyes affected by unilateral central retinal vein occlusions (CRVO) or branch retinal vein occlusions (BRVO). We created and explored a new, unitless metric for the severity of these diseases: relative blood flow (RBF). We then contextualized RBF in terms of patient demographics, ocular presentation and other systemic conditions, as well as explored its efficacy as a predictor of future outcomes. METHODS: Data was collected from 20 control subjects and 32 patients with clinically diagnosed retinal vein occlusions (15 CRVO and 17 BRVO). Laser speckle flowgraphy was then used to quantify retinal vascular blood flow in terms of mean blur rate, a metric shown to be highly heterogeneous between patients but fairly consistent in intra-patient repeated measurements over time. After confirming this and establishing a strong correlation between a healthy patient’s two eyes, we used an RVO patient’s fellow eye as a nondiseased expectation and presented relative blood flow as the ratio between their diseased and healthy eye. We then correlated this data with demographic variables and disease characteristics from patients’ medical history. RESULTS: We found an average blood flow decrease of 26% in CRVO eyes relative to healthy eyes in the same patients and an average decrease of 7% in BRVO eyes. In CRVO, duration of occlusion, central macular thickness, intraocular pressure, diabetes, previous laser and injection treatments, and an injection within three months after blood flow measurement were significantly associated with relative blood flow. In BRVO, no demographic variables or disease characteristics were significantly associated with relative blood flow. CONCLUSIONS: Relative blood flow represents a promising new, consistent and informative metric for quantifying the severity of unilateral retinal vein occlusions. With both descriptive and predictive properties in eyes with CRVO, future work should explore its great potential.
6

Blood flow restriction training for people with chronic obstructive pulmonary disease or heart failure; A scoping review

Ramström, Ivar, Ulman, Kevin January 2024 (has links)
Background: Blood flow restriction training (BFRT) is an effective way of training that enables training with low external load while receiving similar effects to high load training. The lack of knowledge of BFRT for people with chronic obstructive pulmonary disease (COPD) or heart failure (HF) led to the making of this scoping review.  Objective: This scoping review aims to map the existing knowledge, effects, safety, and feasibility of BFRT for people with COPD or heart failure HF. Method: The review followed PRISMAs structure for scoping review. Selection involved title and abstract screening, followed by full text analysis and peer-review by both authors.  Results: A wide variety of study designs was included in this scoping review. Of 11 included studies all were original intervention studies-, whereof 8/11 studies were focused on HF. A large majority of participants were male. Training methods used in intervention studies varied from exercises like leg extensions, leg press and cycling, all while using vascular blood flow restriction. All studies followed different training protocols. The reported outcomes indicated promising improvements like increased functional exercise capacity, muscle strength, reduced symptom burden, and several positive physiological changes for both people with COPD and HF. Some concerns remain regarding the safety of BFRT, but no serious adverse events were reported directly linked to BFRT.  Conclusion: With many reported improvements, BFRT could be a safe and feasible alternative rehabilitation method for people with COPD or HF. Furthermore, with minimal reported adverse events, the method appears safe for both groups. Despite this, the included studies all had small sample sizes, so more high-quality studies with larger sample sizes are needed to give a better understanding on BFRTs effects on both short- and long term. Better studies including females are also needed.
7

Estudos sobre o bloqueio do xilema na pós-colheita das inflorescências de ave-do-paraíso (Strelitzia reginae Aiton) / Studies on the blockage of the xylem in the post-harvest of the bird-of-paradise inflorescences (Strelitzia reginae Aiton)

Marques, Ana Ermelinda 27 February 2008 (has links)
Made available in DSpace on 2015-03-26T13:36:33Z (GMT). No. of bitstreams: 1 texto completo.pdf: 356172 bytes, checksum: 1bf067e3c244857d7b3d148e43e244b1 (MD5) Previous issue date: 2008-02-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The Strelitzia reginae Aiton is known popularly by bird-of-paradise and due to its wide use as cut flower there are still few the studies to evaluate the post-harvest handling and longevity. With the objective of evaluating the vascular occlusion that might take place at the base of the stem, post-harvest solutions containing inhibitors polyphenoloxidase and peroxidase, and reduction of bacterial population were applied. Flowers were pulsed with 10 mM 2-mercaptoethanol, 1 mM AgNO3, 5 mM catechol, 5 mM p-nitrophenol, 10 mM sodium metabissulfite and distilled water without pH adjustment or the pH of the solutions was adjusted for 6.0. Flowers were pulsed with AgNO3 at concentrations of 0.5, 1, 1.5 and 2 mM, sodium metabissulfite and ascorbic acid, both containing 2.5, 5, 7.5 and 10 mM and distilled water. The floral stems of each treatment were evaluated at every 48 hours, period in which were submitted to cuts of 2 cm in their stem base, until the end of the longevity of the flowers. At this time, it was determined the activity polyphenoloxidase and peroxidase. The total fresh matter, relative water content of the sepals, number of open flowers, longevity of the flowers and number of colony forming units per mL (CFU/mL) were evaluated. The activity of the polyphenoloxidase and peroxidase measured from the second to the eighth day after harvest showed that the sodium metabissulfite at 10 mM presented the highest reduction of enzymes activities at the second day of analysis. It was also observed that the solutions containing AgNO3 was not capable to inhibit the growth of the bacterial population in the base of floral stem. Together, the activity of the oxidative enzymes and the high number of colonies of bacteria influenced negatively in the weight of the fresh matter, in the relative water content, in the number of open flowers and in its longevity, because they promoted the precocious senescence of the flowers due to the water stress happened by the low hydraulic conductance of the elements of vase of the xylem. / A Strelitzia reginae Aiton é popularmente conhecida como ave-do-paraíso e devido ao seu amplo uso como flor de corte ainda são poucos os estudos realizados na avaliação dos problemas ocorridos em sua pós-colheita. Com o objetivo de avaliar a oclusão vascular ocorrida no local cortado dos escapos florais, soluções pós-colheita contendo inibidores da atividade das enzimas polifenoloxidase e peroxidase e do crescimento da população bacteriana foram aplicadas em três etapas. Aplicou-se 2-mercaptoetanol 10 mM, AgNO3 1 mM, catecol 5 mM, p-nitrofenol 5 mM, metabissulfito de sódio 10 mM e água destilada sem correção do pH, ou com pH ajustado para 6,0. Aplicou-se também AgNO3 às concentrações 0,5; 1; 1,5 e 2 mM, metabissulfito de sódio e ácido ascórbico, ambos às concentrações 2,5; 5; 7,5 e 10 mM, e água destilada. Os escapos florais de cada tratamento foram avaliados a cada 48 horas, período no qual eram submetidos a cortes de 2 cm em suas bases, até o fim da longevidade das flores. Nesse material coletado avaliou-se a atividade das enzimas polifenoloxidase e peroxidase. As outras observações foram: peso da matéria fresca, teor relativo de água, número de flores abertas, longevidade das flores e número de unidades formadoras de colônias por mL (UFC/mL). A atividade da polifenoloxidase e da peroxidase foi determinada do segundo ao oitavo dia após a colheita e, dos tratamentos aplicados, o metabissulfito de sódio 10 mM apresentou a maior redução da atividade das enzimas após o segundo dia da aplicação. As soluções contendo AgNO3 não foram capazes de inibir o crescimento da população bacteriana nos escapos florais. Em conjunto, a atividade das enzimas oxidativas e o alto número de colônias de bactérias influenciaram negativamente no peso da matéria fresca, no teor relativo de água, no número de flores abertas e na sua longevidade, pois promoveram a senescência precoce das flores devido ao estresse hídrico ocorrido pela baixa condutância hidráulica dos elementos de vaso do xilema.
8

Envolvimento da peroxidase e polifenoloxidase no bloqueio xilemático de hastes de ave-do-paraíso (Strelitzia reginae) / Involvment of peroxidase and polyliphenoloxyidase in the vascular occlusion of stalks of bird-of-paradise (Strelitzia reginae)

Karsten, Juliane 16 February 2009 (has links)
Made available in DSpace on 2015-03-26T13:36:39Z (GMT). No. of bitstreams: 1 texto completo.pdf: 655720 bytes, checksum: 45203cde01cfaaa9a0bd784688103fd6 (MD5) Previous issue date: 2009-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The goals of this work were to determine the time in which occurs the vascular occlusion and the contribution of the peroxidase (POD) and polyphenoloxidase (PPO) in this process; partially purify and characterize these enzymes and verify the effect of the use of enzymatic inhibitors combined or not with sucrose in the pulsing solution on the postharvest life of the bird-of-paradise. To determine the time of occlusion, the stalks were dry stored for different periods of time (0, 8, 16, 24, 32, 40 and 48 hours), and after being placed in water. The variation of fresh mass and the relative water content (RWC) of the sepals were evaluated within the first 24 hours, and the POD and PPO activity were determined after 100 hours. Harvested flowers were immediately placed in water and had their fresh mass variation, and POD and PPO activity daily evaluated up to 8th day, when the first floret was complete wilted. Flowers maintained for 16 hours under dry storage recuperated the initial fresh mass index and RWC after being placed in water, suggesting that the vascular occlusion occured after 16 hours of dry storage. The POD activity was higher in control stalks and the PPO was higher in stalks which suffered moderated water stress (16, 24, 32 and 40 hours). Throughout the vase life, the POD activity reached the highest level in the 8th day of vase life, and the PPO was kept constant. The POD activity was higher than the PPO in all the analyses, suggesting a higher influence of the POD in the xylematic occlusion of this specie. In the process of enzymatic characterization, the ideal pH and the optimum temperature for both enzymes were determined, as well as the optimum substrate for the PPO. The stability in different pHs, thermal stability and the effect of different inhibitors were also observed. The highest activity of POD was found in pH 5.0 and 60ºC, and the prexi incubation for 120 minutes in pH 2.5 and 25ºC lead to the inhibition of 93.1% of the initial activity, 120 minutes in 70ºC to 98.7% of inhibition and 80ºC for 10 minutes or 90ºC for 1 minute lead to complete inactivation. A complete inhibition of this enzyme was also achieved in the presence of different inhibitors, like ascorbic acid, L-cysteine, sodium metabissulfite, sodium azide, &#946;-mercaptoethanol and DTT. The PPO presented the highest activity with 4-methylcatecol as substrate, in pH 6.0 and 40ºC. Complete inactivation of this enzyme was obtaining by incubating for 10 minutes at 80ºC or using 1 mM of DTT, L-cisteyne, sodium metabissulfite and &#946;-mercaptoethanol. Finally, different pulsing solutions containing enzymatic inhibitors, combined or not with sucrose 40% were applied for 24 hours. The fresh mass variation, RWC and number of open florets were daily determined, and the longevity was determined until the wilting of the last opened floret. From the inhibitors applied alone, the sodium azide was able to provide the highest values of fresh mass, longest longevity and highest number of open florets. Combined with sucrose, the ascorbic acid and the sodium azide were able to provide the best results, with the highest number of open florets and longer longevity. The occlusion of xylematic vessels of this specie is related to the POD and PPO activity and the use of pulsing solutions containing enzymatic inhibitors is a viable technique to extend the vase life of bird-of-paradise of flowers. / Os objetivos deste trabalho foram: determinar o momento de ocorrência do bloqueio vascular e a contribuição da peroxidase (POD) e polifenoloxidase (PPO) neste processo; purificar parcialmente e caracterizar essas enzimas; e verificar o efeito da utilização de inibidores enzimáticos combinados ou não com sacarose na solução de pulsing sobre a vida pós-colheita de ave-do-paraíso. Para determinar o tempo para a oclusão, hastes florais foram armazenadas a seco por diferentes períodos (0, 8, 16, 24, 32, 40 e 48 horas), e após foram colocadas na água. A variação de massa fresca e o teor relativo de água (TRA) das sépalas foram avaliados nas primeiras 24 horas, e a atividade da POD e PPO foram determinadas após 100 horas. Flores colhidas e colocadas imediatamente na água, tiveram sua variação de massa fresca, e atividade da POD e PPO avaliadas diariamente até o 8º dia, quando o 1º florete estava completamente seco. Flores mantidas por até 16 horas em armazenamento a seco, recuperaram os valores de massa fresca e TRA iniciais após serem mantidas em água, sugerindo que o bloqueio vascular esteja ocorrendo após essas 16 horas. A atividade da POD foi maior em hastes controle e a da PPO em hastes que sofreram estresse hídrico moderado (16, 24, 32 e 40 horas). Ao longo da vida de vaso, a atividade da POD alcançou maiores níveis após o 8º dia da vida de vaso, e a da PPO manteve-se constante. A atividade da POD foi superior a da PPO em todas as análises, sugerindo uma maior influência da POD no bloqueio xilemático desta espécie. No processo de caracterização enzimática, o pH ideal e a temperatura ótima para ambas as enzimas foi determinado, bem como o substrato ótimo para a PPO. A estabilidade a diferentes pHs, estabilidade térmica e o efeito de diferentes inibidores também foram acompanhados. Maior atividade da POD foi encontrada em pH 5,0 e 60ºC, e a pré-incubação por 120 minutos em pH 2,5 a 25ºC levou a inibição de 93,13% da atividade inicial, 120 minutos a 70ºC a 98,69% de inibição, e a 80ºC por 10 minutos ou 90ºC por 1 minuto levou a inativação completa. Uma completa inibição desta enzima também foi encontrada na presença de diferentes inibidores, como ácido ascórbico, L-císteina, metabissulfito de sódio, sódio azida, &#946;-mercaptoetanol e DTT. A PPO apresentou maior atividade com 4-metil-catecol como substrato, em pH 6,0 e 40ºC. Inativação completa desta enzima foi obtida com pré-incubação por 10 minutos a 80ºC ou usando 1 mM de DTT, L-cisteína, metabissulfito de sódio e &#946;-mercaptoetanol. Finalmente, diferentes soluções de pulsing contendo inibidores enzimáticos, combinados ou não com sacarose 40% foram aplicadas por 24 horas. A variação de massa fresca, TRA e o número de floretes abertos foram determinados diariamente, e a longevidade foi acompanhada até o murchamentodo último florete aberto. A partir dos inibidores aplicados sozinhos, o sódio azida foi que proporcionou maiores valores de massa fresca, maior longevidade e maior número de floretes abertos. Combinados com sacarose, o ácido ascórbico e o sódio azida foram capaz de proporcionar os melhores resultados, com maior número de floretes abertos e maior longevidade. O bloqueio dos vasos xilemáticos desta espécie está relacionado à atividade da POD e PPO e o uso de soluções de pulsing contendo inibidores enzimáticos é uma técnica eficiente em prolongar a vida de vaso de flores de ave-doparaíso.
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Estudo de marcadores de prognóstico em crianças com doença flaciforme e sua associação com colonização de nasofaringe e orofaringe / Estudo de marcadores de prognóstico em crianças com doença flaciforme e sua associação com colonização de nasofaringe e orofaringe

Rocha, Larissa Carneiro January 2011 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-07-20T21:34:48Z No. of bitstreams: 1 Larissa Carneiro Rocha.pdf: 1632038 bytes, checksum: 82deed6171da78f07c96b948629b2896 (MD5) / Made available in DSpace on 2012-07-20T21:34:48Z (GMT). No. of bitstreams: 1 Larissa Carneiro Rocha.pdf: 1632038 bytes, checksum: 82deed6171da78f07c96b948629b2896 (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / A doença falciforme (DF) possui prevalência mundial elevada e manifestação clinicamente variável, sendo que as infecções constituem risco elevado e causa de óbito nas crianças diagnosticadas com anemia falciforme (HbSS). A colonização da nasofaringe pode ser fator importante para a ocorrência de doença local ou sistêmica. O Streptococcus pneumoniae é um patógeno de importância epidemiológica mundial e causador de infecções entre os pacientes com DF. A prevalência da colonização pelo pneumococo em nasofaringe varia de acordo com a população estudada e condições ambientais. O Staphylococcus aureus também pode colonizar a nasofaringe, além de causar infecção de pele e tecidos moles, pneumonia, septicemia e infecções ósteo-articulares. Diferentes biomarcadores têm sido associados à modulação clínica na DF e eles são comumente associados à hemólise e inflamação. O presente estudo teve como objetivo estabelecer o perfil de biomarcadores em indivíduos com DF associando-os ao perfil de colonização nasofaríngea e orofaríngea, com ênfase para os marcadores de infecção e hemólise que possam estar associados ao prognóstico clínico dda doença. As análises bioquímicas foram realizadas para a avaliação do perfil lipídico, hepático, inflamatório e hemolítico; marcadores clássicos de biologia molecular, como a talassemia α, os haplótipos ligados aos genes da globina beta e os polimorfismos no gene da mieloperoxidase foram também investigados. Desta forma, foi desenvolvido um estudo de corte transversal, com casuística composta por 154 pacientes com DF em idade pediátrica e em estado estável da doença, sendo 68,2% (105/154) HbSS e 31,8% (49/154) com doença SC (HbSC), todos provenientes do estado da Bahia. As crianças HbSS apresentaram diferenças significativas na grande maioria das variáveis laboratoriais analisadas e associadas ao metabolismo lipídico, renal, hepático e à hemólise e inflamação, quando comparadas ao grupo HbSC e ao controle saudável. A colonização em nasofaringe/orofaringe pelo S. pneumoniae esteve presente em 14 (9,6%) pacientes e pelo S. aureus em 81(56,6%) pacientes. Quanto ao perfil de sensibilidade dos isolados de pneumococos da população estudada, não foi observado o aumento da resistência pneumocócica à penicilina. A avaliação de modelos de análise multivariada demonstrou que a presença de colonização nasofaríngea e orofaríngea esteve associada à ocorrência de infecção juntamente com a contagem de leucócitos, sendo que o genótipo exibido pelo paciente foi fator de risco para a ocorrência de pneumonia. Os mesmos modelos apontaram o envolvimento dos polimorfonucleares neutrófilos na ocorrência de vaso-oclusão. Os resultados demonstram que os pacientes colonizados em nasofaringe pelo S. pneumoniae e pelo S. aureus apresentaram elevação dos valores de HCM, VCM, AST, ALT e Ferritina; investigações rotineiras de biomarcadores clássicos associados ao estudo da colonização de nasofaringe e orofaringe podem ter papel importante no acompanhamento da evolução clinica de indivíduos com DF, uma vez que os achados significativos sugerem que a presença de colonização tem papel importante na modulação dos eventos hemolítico, inflamatório e infeccioso presentes na doença. / The sickle cell disease (SCD) has a high prevalence worldwide and a variable clinical manifestation and infections are considered an event of high risk and cause of death in children diagnosed with sickle cell anemia (HbSS). The colonization of nasopharynx and oropharynx can be an important factor for the occurrence of local or systemic disease. The Streptococcus pneumoniae is a pathogen of epidemiological importance worldwide and cause of infection among SCD patients. The Staphylococcus aureus may also colonize the nasopharynx and may be cause of infection of skin and soft tissue infections, pneumonia, sepsis and osteo-articular infections. Different biomarkers have been associated with clinical modulation in SCD and they are commonly associated with hemolysis and inflammation. This study aimed to establish a profile of biomarkers in individuals with SCD in association with the profile of oropharyngeal and nasopharyngeal colonization, with emphasis on infection and hemolysis markers that may be associated with clinical prognosis. Biochemical analysis were performed to evaluate the lipid profile, liver, hemolytic and inflammatory markers and classical molecular biology, such as α-thalassemia, the haplotypes linked to the beta globin genes and polymorphisms in the myeloperoxidase gene were also investigated. Thus, it was developed a cross-sectional study and the casuistic was composed of 154 children with SCD in a steady-state, with 68.2% (105/154) HbSS and 31.8% (49/154) with SC disease (HbSC), all from the state of Bahia. HbSS children showed significant differences in almost every mean values analyzed for variables associated with lipid metabolism, kidney, liver and hemolysis and inflammation when compared to HbSC and control group. In the present study there was colonization in the nasopharynx / oropharynx by S. pneumoniae in 14 (9.6%) patients and by S. aureus in 81 (56.6%) patients. The profile of sensitivity of pneumococcal isolated from the studied population did not show an increase in pneumococcal resistance to penicillin. The evaluation of models of multivariate analysis showed that the presence of oropharyngeal and nasopharyngeal colonization was associated with the occurrence of infection and white blood cell count, and the patient genotype was a risk factor for the occurrence of pneumonia. The same models indicated the involvement of polymorphonuclear neutrophils in the occurrence of vaso-occlusion. The results presented in this study demonstrate that patients colonized in the nasopharynx by S. pneumoniae and S. aureus have elevated values of MCH, MCV, AST, ALT and ferritin, suggesting that a routine investigation of biomarkers associated with the classic study of the colonization of the nasopharynx and oropharynx may play a role in monitoring the clinical course of patients with SCD, once that significant findings described here suggest that the presence of colonization plays an important role in modulation of hemolytic events, inflammatory state, and infectious presented by patients.
10

Modelling of the mechanobiological adaptation to vascular occlusion in the arterial tree / Modelado de la adaptación mecanobiológica de la oclusión vascular en el árbol arterial

Rodríguez María, Jaime January 2016 (has links)
It is known that there are many cardiovascular diseases caused by the alterations in the blood vessels, that affect most of the world population. The knowledge of the mechanobiological behavior of blood vessels is used for understanding how cardiovascular diseases could affect the human body. So, by studying the growth and remodeling (G&amp;R) of the arterial tree, it is possible to predict how these diseases will develop and consequently, how they can be treated or even prevented. The human body naturally tries to find the optimum steady-state by changing either the production of the constituents of the arteries or the flow rate through blood vessels. This effect is the phenomenon that is going to be studied in this thesis and these three main factors have to be taken into account when reproducing the diseases’ effects: the so-called transmural pressure, the blood flow rate, and the biomechanics of the constituents which form the arterial wall. Therefore, through numerical simulations the variation of these factors can be predicted, although always with a reliability supported by experimental data. / Se sabe que hay muchas enfermedades cardiovasculares causadas por alteraciones en los vasos sanguíneos que afectan gran parte de la población mundial. El conocimiento del comportamiento mecanobiológico de los vasos sanguíneos se usa para entender cómo estas enfermedades puede afectar al cuerpo humano. Así, estudiando el crecimiento y desarrollo (G&amp;R) del árbol arterial, es posible predecir cómo estas enfermedades se van a desarrollar y consecuentemente, cómo pueden tratarse o incluso prevenirse. El cuerpo humano tiende a buscar un estado de equilibrio óptimo de forma natural cambiando o bien la producción de los constituyentes de las arterias o bien el flujo de sangre que atraviesa los vasos sanguíneos. Este efecto es el fenómeno que va a ser estudiado en esta tesis y se ha de tener en cuenta tres factores principales cuando se quiere reproducir los efectos de dichas enfermedades: la presión transmural, el flujo de sangre y la biomecánica de los constituyentes que forman la pared arterial. Luego, a través de simulaciones numéricas la variación de estos factores puede ser predicha, aunque siempre con una veracidad aportada por datos experimentales. / Vascular occlusion, modelling, arteries, arterial tree, growth and remodelling, Murray, cerebrocardiovascular diseases, adaptation, thrombosis, calcification, anemia, polycythemia, isquemia, edema

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