No description available.

No description available.

No description available.

Burn-induced intestinal barrier failure has been proposed to be a potential cause of subsequent multiple organ failure after burn. Studies have shown that the increased iNOS activity is closely related to intestinal and pulmonary damage in rats after burn. Expression of iNOS and MMP-9 is regulated by nuclear factor NF-£eB activation, which is frequently a result of MAPKs pathway activation. This study was to investigate the role of ERKs in intestinal and pulmonary damage induced by burn in rats. In experiments, SD rats underwent 30 ~ 35 % TBSA burn. At various times after burn, intestinal mucosa and pulmonary proteins were assayed for ERKs and p38 phosphorylation by immunoblotting, nuclear extracts were assayed for NF-£eB activation by EMSA, intestinal and pulmonary iNOS, MMP-9 expressions were evaluated by RT-PCR, the FITC-dextran permeability was determined to assess the intestinal barrier function and the pulmonary microvascular dysfunction was quantitated by measuring the extravasation of Evans blue dye. The results show that burn induced ERKs and p38 phosphorylation, the expression of iNOS, and NF-£eB activation in intestinal mucosa and lung, but the expression of MMP-9 was attenuated. Treatment with MEK1/2 inhibitors, PD98059 (10 mg/kg i.p.) or U0126 (5 mg/kg i.p.) immediately after burn, attenuated the phosphorylation of intestinal mucosa and pulmonary ERKs, the activation of NF-£eB, the increase in intestinal permeability, and pulmonary microvascular dysfunction. Interestingly, the expression of iNOS in intestinal mucosa and pulmonary tissues was induced by PD98059 administration, but the expression of MMP-9 in intestinal mucosa was attenuated by PD98059 administration. These results suggest that the tissue damage is regulated by NF-£eB activation and the activation of NF-£eB is primarily mediated by signal pathway of ERKs in burn-injured rats, so the signal transduction pathway may involve ERKs and p38, NF-£eB, iNOS or MMP-9, then causes tissue damage. Further, burn-induced intestinal mucosa and pulmonary ERKs have different degree of activation. The p38 and ERKs phosphorylation showed a two-step activation in intestinal mucosa and pulmonary tissues after burn. Inhibition of intestinal and pulmonary ERKs in vivo afforded significant protection against burn-induced barrier failure. However, the data showed that iNOS may not play a major role in the burn-induced intestinal and pulmonary damage, and MMP-9 may have more affect on tissues damage.

No description available.

The primary purpose of this work was to evaluate the capability of nanoparticles to transform electromagnetic energy at microwave frequencies into therapeutic heating. Targeted nanoparticles, in conjunction with microwave irradiation, can increase the temperatures of the targeted area over the peripheral region. Therefore, to become clinically viable, microwave absorbing nanoparticles must first be identified, and a system to monitor the treatment must be developed. In this study, ultrasound temperature imaging was used to monitor the temperature of deep lying structures. First, a material-dependent quantity to correlate the temperature induced changes in ultrasound images (i.e. apparent time shifts) to differential temperatures was gathered for a tissue-mimicking phantom, porcine longissimus dorsi muscle, and porcine fat. Then microwave nanoabsorbers were identified using an infrared radiometer. The determined nanoabsorbers were then injected into ex-vivo porcine longissimus dorsi muscle tissue. Ultrasound imaging frames were gathered during microwave treatment of the inoculated tissue. Finally, the ultrasound frames were analyzed using the correlation between temperature and apparent shifts in ultrasound for porcine muscle tissue. The outcome was depth-resolved temperature profiles of the ex-vivo porcine muscle during treatment. The results of this study show that magnetite is a microwave nanoabsorber that increases the targeted temperature of microwave hyperthermia treatments. Overall, there is clinical potential to use microwave nanoabsorbers to increase the efficiency of microwave hyperthermia treatments. / text

A energia ultra-sônica é um dos recursos físicos amplamente utilizado e pesquisado nos tratamentos de fisioterapia e diagnósticos médicos. Sabe-se que diante de uma escassa literatura dos efeitos do ultra-som em tecidos sadios, muitos profissionais fisioterapeutas acabam realizando aplicações infundadas de métodos e parâmetros. O objetivo desta pesquisa foi avaliar possíveis alterações do tecido sadio in vivo de ratos Wistar irradiados com diferentes intensidades, analisando a histologia e morfometria. Foram utilizados 30 ratos da linhagem Wistar, distribuídos aleatoriamente em 5 grupos de 6 animais cada. Foi escolhida a região dorsal do lado direito para tratamento com área de 4 \'CM POT.2\'. O lado esquerdo serviu como controle em todos os grupos. O tratamento foi feito durante 4 dias com 2 minutos de irradiação. Para verificar a intensidade de saída, utilizou-se o dosímetro de precisão antes da aplicação do ultra-som em cada animal. Foi realizada uma análise histológica descritiva e morfometria por meio do software Image Tool. Como resultado pode-se observar um discreto infiltrado inflamatório e adelgaçamento das fibras da derme, principalmente dos grupos irradiados com 1.5 e 2 W/\'CM POT.2\'. Notou-se também um aumento na espessura da epiderme nas amostras dos animais irradiados quando comparado com o controle. Para avaliar os resultados quantitativos, utilizou-se como análise estatística ANOVA \"one way\" e o teste \"pos hoc\" de Tukey com nível de significância p < 0,01. Em 120 medidas da espessura da epiderme obtiveram-se diferenças significativas do grupo controle com os grupos irradiados com (1.0, 1.5 e 2.0 W/\'CM POT.2\'). Concluímos diante dos resultados que houve alterações no tecido sob ação do US nas doses maiores, o que nos alerta para possíveis implicações do uso do US em estética. / The ultrasound (US) energy is one of the resources widely used and researched in both physio-therapist treatment and in medical diagnosis. In front of a scarce literature about the US effects in healthy tissues, many professionals have carried out unfounded applications of methods and parameters. So, the aim of this research was evaluate, through the histology, possible alternations in healthy tissues of Wistar rats in vivo irradiated with different intensity, analyzing the qualitative and quantitative histological slides. We used 30 Wistar rats randomly distributed in 5 groups of animals each. The local chosen for receiving the treatment was the dorsal right side, whose area was 4 \'CM POT.2\'. The left side was used as control of the animal itself for all the groups. The rats underwent the treatment during 4 days exposed to 2 minutes of irradiation. In order to check the energy output, the precision dosimeter was used before US application in each animal. The histological slides were evaluated qualitatively in the microscope and quantitatively through the image tool software. The qualitative result shows a discrete inflammatory process with infiltration and atrophy dermis fibers, mainly in the groups with higher US dosage. In the quantitative aspect, we found epidermis thickness increased in the 1.5 and 2 W/\'CM POT.2\' of US, with statistical difference (ANOVA) compared to control. We conclude that US therapy can be dangerous with high dosage applied in the intact skin.

A energia ultra-sônica é um dos recursos físicos amplamente utilizado e pesquisado nos tratamentos de fisioterapia e diagnósticos médicos. Sabe-se que diante de uma escassa literatura dos efeitos do ultra-som em tecidos sadios, muitos profissionais fisioterapeutas acabam realizando aplicações infundadas de métodos e parâmetros. O objetivo desta pesquisa foi avaliar possíveis alterações do tecido sadio in vivo de ratos Wistar irradiados com diferentes intensidades, analisando a histologia e morfometria. Foram utilizados 30 ratos da linhagem Wistar, distribuídos aleatoriamente em 5 grupos de 6 animais cada. Foi escolhida a região dorsal do lado direito para tratamento com área de 4 \'CM POT.2\'. O lado esquerdo serviu como controle em todos os grupos. O tratamento foi feito durante 4 dias com 2 minutos de irradiação. Para verificar a intensidade de saída, utilizou-se o dosímetro de precisão antes da aplicação do ultra-som em cada animal. Foi realizada uma análise histológica descritiva e morfometria por meio do software Image Tool. Como resultado pode-se observar um discreto infiltrado inflamatório e adelgaçamento das fibras da derme, principalmente dos grupos irradiados com 1.5 e 2 W/\'CM POT.2\'. Notou-se também um aumento na espessura da epiderme nas amostras dos animais irradiados quando comparado com o controle. Para avaliar os resultados quantitativos, utilizou-se como análise estatística ANOVA \"one way\" e o teste \"pos hoc\" de Tukey com nível de significância p < 0,01. Em 120 medidas da espessura da epiderme obtiveram-se diferenças significativas do grupo controle com os grupos irradiados com (1.0, 1.5 e 2.0 W/\'CM POT.2\'). Concluímos diante dos resultados que houve alterações no tecido sob ação do US nas doses maiores, o que nos alerta para possíveis implicações do uso do US em estética. / The ultrasound (US) energy is one of the resources widely used and researched in both physio-therapist treatment and in medical diagnosis. In front of a scarce literature about the US effects in healthy tissues, many professionals have carried out unfounded applications of methods and parameters. So, the aim of this research was evaluate, through the histology, possible alternations in healthy tissues of Wistar rats in vivo irradiated with different intensity, analyzing the qualitative and quantitative histological slides. We used 30 Wistar rats randomly distributed in 5 groups of animals each. The local chosen for receiving the treatment was the dorsal right side, whose area was 4 \'CM POT.2\'. The left side was used as control of the animal itself for all the groups. The rats underwent the treatment during 4 days exposed to 2 minutes of irradiation. In order to check the energy output, the precision dosimeter was used before US application in each animal. The histological slides were evaluated qualitatively in the microscope and quantitatively through the image tool software. The qualitative result shows a discrete inflammatory process with infiltration and atrophy dermis fibers, mainly in the groups with higher US dosage. In the quantitative aspect, we found epidermis thickness increased in the 1.5 and 2 W/\'CM POT.2\' of US, with statistical difference (ANOVA) compared to control. We conclude that US therapy can be dangerous with high dosage applied in the intact skin.

Extravasation is a condition that can occur during an intravenous administration. This means that the solution administered intravenously goes extravascular. Depending on physiochemical properties of the substance and solution, this can cause different severity of the damage. Extravasation of acyclovir, potassium phosphate and potassium chloride causes severe tissue damage that can, in worst case, lead to tissue necrosis. The purpose was therefore to investigate how acyclovir, potassium phosphate and potassium chloride causes tissue damage due to pH and osmolality and how the tissue damage can be avoided. To answer the purpose, a comprehensive literature search was conducted on three different databases; Pubmed, CINAHL and Cochrane. The literature search was in progress from February 4 to May 14 2020. The literature search generated a total of 42 articles and case reports, of which 13 of these were relevant for the purpose. These 13 articles consisted of two animal studies, three experimental observational studies, two guidelines from Västra Götalands Region, three case reports about acyclovir and three case reports of potassium phosphate and potassium chloride.   Two of the experimental observational studies showed that potassium chloride could be diluted with 100 mL of 0,9% sodium chloride or 5% dextrose in water to possibly avoid tissue damage due to extravasation. Such results were not found for either acyclovir or potassium phosphate. The conclusion that could be drawn was that acyclovir caused tissue damage because of its alkaline pH, potassium phosphate because of its hyperosmolality and potassium chloride because of its acidic pH and its hyperosmolality. One way to possibly avoid tissue damage caused by extravasation is to dilute the substances with higher dilution volumes. However, due to the lack of reliability of the included studies, it cannot be safely concluded that tissue damage can be avoided.

Needles are commonly used to reach target locations inside of the human body for various medical interventions such as drug delivery, biopsy, and brachytherapy cancer treatment. The success of these procedures is highly dependent on whether the needle tip reaches the target. One of the most significant contributors to the target accuracy is the needle insertion force that causes needle-tip deflection, tissue deformation, and tissue damage. Recently there has been tremendous interest in the medical community to develop innovative surgical needles using biologically-inspired designs. It is well known that insects such as honeybee and mosquito steer their stingers effortlessly to a specific target and release their venom in a certain path through the skin with minimal force. These unique traits inspire this dissertation work to develop bioinspired needles and to study the insertion mechanics of these needles for reducing the insertion force, needle-tip deflection, tissue deformation, and tissue damage. In this work, the insertion mechanics of honeybee-inspired needles with applied vibration in polyvinyl chloride (PVC) tissue phantom and chicken breast tissues was first investigated. It was observed that the insertion force was decreased by 43% and the needle tip deflection was minimized by 47% using honeybee-inspired needles. Furthermore, the insertion mechanics of mosquito-inspired needles in PVC tissue phantom and bovine liver tissues were studied. Design parameters such as maxilla design on the needle body, labrum-tip, vibration, and insertion velocity were considered. It was found that the insertion force was reduced by 60% in PVC tissues and 39% in bovine liver tissues using mosquito-inspired needles. To validate the developed bioinspired needle prototypes, a size scale study was performed using insertion test in a PVC tissue phantom. It was confirmed that the insertion force was decreased by 38% using different needle sizes. An analytical LuGre friction model was used to explain the insertion mechanics and to confirm the experimental results. Lastly, to investigate the effect of the insertion force reduction, the tissue deformation and the tissue damage studies were performed. Using a novel magnetic sensing system, it was observed that the tissue deformation caused by mosquito-inspired needles was decreased by 48%. A histological study was performed to quantify the tissue damage in bovine liver tissues. It was observed that the tissue damage of mosquito-inspired needles was reduced by 27% compared to standard needles. In conclusion, this dissertation study shows that applying bioinspired needle designs and vibration during insertion into tissues reduces the insertion force, the needle-tip deflection, the tissue deformation, and the tissue damage. The outcome of this study will benefit medical communities to advance the bioinspired needles for vibration-assisted clinical procedures. / Mechanical Engineering