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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.
231

Effects of ultrasound field distance of low-intensity pulsed ultrasound (LIPUS) on rat fracture healing and osteocyte-osteoblast paracrine signalling. / CUHK electronic theses & dissertations collection

January 2012 (has links)
临床及动物实验的文献报告表明, 低能量脉冲超声波 (LIPUS) 能促进骨折愈合。 可是, 不同研究小组针对LIPUS的功效所提供的数据结果往往并不一致。为了找出导致数据结果不一致的原因, 以及提升LIPUS的生物功效, 科研人员正致力于测定超声波在骨折治疗中的最佳信号参数。 在临床运用上, LIPUS对骨折的治疗一般是以经皮方式应用的。 故此, 不同层次深度的骨折会暴露在不同的超声波场区里。 超声波场有两个不同的区域, 就是近场区 (接近超声波换能器的区域) 及远场区 (远离超声波换能器的区域)。 在我们早期的临床研究中, 我们曾使用超声波的近场区治疗胫骨的复杂性骨折。 我们发现, 当超声波换能器置于胫骨骨折处的前方, 骨痂集中生成于胫骨骨折处的背面。 这研究结果显示, 近场区以外的超声波场或许更具促进骨痂形成的功效。 再者, 针对LIPUS声场仿真分析的结果显示, 近场区内的声压分布是不稳定的, 而远场区内的声压则远比近场区的均及稳定。由于声压的稳定性会大大影响超声波于组织内的能量透射, 我们相信在超声波场中, 骨折的深度会影响LIPUS的生物效应。 / 本研究采用大鼠闭合性股骨骨折模型及细胞培养实验, 探究不同的超声波场区对骨折愈合的影响。本研究作出了以下三个科研假设: (1) LIPUS 的远场区在促进骨折愈合的应用上有着更高的生物效应; (2) LIPUS 的远场区能透过促使骨细胞产生旁分泌调节因子, 从而提升成骨细胞的成骨活性; (3) 通过换能器直径的调制而产生的LIPUS远场区能有效地促进骨折愈合。 / 在第一部分的实验里, 股骨骨折的SD大鼠被随机分为对照组 (control), 近场区超声波治疗组 (near field; 伤肢跟换能器相距0mm), 中近场区超声波治疗组 (mid-near field; 伤肢跟换能器相距60mm), 远场区超声波治疗组 (far field; 伤肢跟换能器相距130mm)。在伤肢及超声波换能器之间安放了跟软组织具有同一超声波衰减系数的凝胶 (长度: 0mm, 60mm, 130mm)。LIPUS每天治疗20分钟, 每周治疗5天。 我们研究结果显示, 治疗后的第四周, 远场治疗组的骨痂组织具有各组中最高的相对骨体积及组织矿密度, 这造就远场治疗组相比对照组具有更强的力学属性。我们的研究结果表明, LIPUS的远场区治疗能通过提升骨痂的骨体积及骨矿化, 进一步促进骨折的愈合。 / 在第二部分的实验里, 我们把骨细胞株(MLO-Y4) 暴露在三種不同的超声波場中: 0 mm, 60 mm 及130 mm 。 经过不同的LIPUS处理后, 我们把条件培养基(CM) 收集, 并将其用于培养成骨前趋细胞株(MC3T3-E1)。 这部分的实验共有5组: Non组(非条件培养基处理组), Con组(骨细胞条件培养基处理组), 0mm组(条件培养基处理组; 条件培养基收集自经过LIPUS近场区刺激后的骨细胞), 60mm组(条件培养基处理组; LIPUS中近场区刺激后的骨细胞), 以及 130mm组(条件培养基处理组; LIPUS远场区刺激后的骨细胞)。我们测试了各超声波场对骨细胞的直接影响, 以及成骨前趋细胞经过各类骨细胞条件培养基培养后的成骨活性。 免疫染色的结果显示近场区以后的超声波场 (130mm 及 60mm) 能进一步诱导β-catenin 于骨细胞的入核作用。 另外, 远场区的骨细胞条件培养基 (130mm CM) 的处理促进了成骨前趋细胞的: (1) 细胞迁移的能力 (反映自细胞伤口愈合测试) ; (2) 细胞分化成熟的机制 (BrdU细胞增殖检验及ALP活性分析): (3) 基质钙化 (Alizarin red 钙化结节染色)。 / 在第三部分的实验里, 我们把换能器的直径缩减致一半, 以致换能器跟LIPUS远场区之间的距离从130 mm被拉近至30 mm。 当LIPUS以经皮的方式应用, 位于皮下大约40 mm的大鼠股骨骨折因此暴露在LIPUS的远场区。 相对于在换能器及伤肢之间安置130 mm凝胶, 以调制换能器直径而直接让骨折暴露于LIPUS远场区是更具临床应用性的方法。 在这部分, 股骨骨折的SD大鼠被随机分为对照组 (control), LT-Near30 (正常的换能器直径; 近场超声处理; I[subscript SATA] = 30 mW/cm²), ST-Far30 (缩减后的换能器直径; 远场超声处理; I[subscript SATA] = 30 mW/cm²), ST-Far150 (缩减后的换能器直径; 远场超声处理; I[subscript SATA] = 150 mW/cm²)。 研究结果证实, 以调制换能器直径而产生的远场LIPUS (ST-Far30)能透过提升骨痂的生成及力学属性, 进一步促进骨折愈合。 同时, 我们的结果显示, 相对高强度 (150 mW/cm²) 的远场LIPUS治疗不能更有效地促进骨折愈合。 / 综上所述, 动物及细胞培养实验结果证明, LIPUS的远场区在促进骨折愈合上更具功效。由于LIPUS的远场区放射稳定的超声波束, 骨痂中的骨细胞受引发释放可溶性因子, 从而进一步激发成骨样细胞的成骨活性。 这些细胞的生物效应造就LIPUS的远场区在促进骨折愈合上更具治疗效果。最后, 我们亦把以上的研究发现转化成具临床应用性的LIPUS应用方法。 这应用方法能让超声波换能器以紧贴皮肤的方式直接使骨折暴露于LIPUS远场区, 从而达成促进骨折愈合的功效。 / Low-intensity Pulsed Ultrasound (LIPUS) has been confirmed to enhance fracture healing in many clinical and animal studies. However, the evidences from literatures to support the applications of LIPUS on fracture healing were inconsistent. Therefore, scientists have been studying various ultrasound parameters aiming to find out the factors resulting in the inconsistent outcomes among research groups, and to further enhance the efficacy of LIPUS. Clinically, LIPUS is usually applied onto fracture sites transcutaneously, hence, fractures at different depths are exposed to different zones of ultrasound beam. There are two characteristic zones of ultrasound beam: the near field (close to the transducer) and far field (farther from the transducer). In our previous clinical study, direct transcutaneously applied LIPUS (near field LIPUS exposure) was used to treat human tibial complex fractures. We found that callus usually formed on the posterior side when the transducer was placed on the anterior side. This finding implied that ultrasound beam beyond near field bears higher potential in promoting callus formation. Moreover, beam mapping measurement of LIPUS shows a variable spatial pressure in near field; while a more uniform pressure profile was found beyond it (far field). As the stability of pressure profile influences the ultrasound energy transmission in tissue, we postulate that the biological effects of LIPUS are affected by the fracture depths within the ultrasound field. / This study aims to address the research question of how ultrasound fields influence the fracture healing through testifying the following hypotheses in animal and cell culture studies: (1) Far field LIPUS bears higher biological effect in facilitating fracture healing; (2) Far field LIPUS could enhance the osteogenic activities of osteoblastic cells via paracrine factors secreted from osteocytes; (3) Far field LIPUS setup by transducer diameter modulation could facilitate fracture healing. / In part one study, femoral fractured Sprague-Dawley (SD) rats were randomized into control, near-field (fractures placed at 0mm away from transducer), mid-near field (60mm away from transducer) or far-field (130mm away from transducer) groups. Rubber gel block (lengths: 0mm, 60mm and 130mm) with attenuation coefficient equivalent to soft tissue was interposed between the transducer and the fractured limb. LIPUS was given 20min/day and 5days/week. We found the callus in 130mm group was the highest in bone volume fraction and tissue mineral density at week 4. These advancements mutually contributed to its significantly stronger mechanical properties than the control group. Our results indicated that far field LIPUS could further facilitate fracture healing by promoting bone volume increase and callus mineralization, which led to enhanced mechanical properties. / In part two study, LIPUS was applied to osteocyte cell line (MLO-Y4) at three distances: 0mm, 60mm and 130mm. The conditioned medium (CM) collected from different LIPUS treatment regimens were used to culture pre-osteoblast cell line (MC3T3-E1). There were 5 groups in the CM treatment: Non group (plain α-MEM treatment), Con group (osteocyte CM), 0mm group (Near field LIPUS treated osteocyte CM), 60mm group (Mid-near field LIPUS treated osteocyte CM) and 130mm group (Far field LIPUS treated osteocyte CM). The effect of ultrasound fields on osteocytes and the osteogenic activities of the pre-osteoblasts after different CM treatments were assessed. The immunostaining results indicated that beyond near field LIPUS (LIPUS at 130mm and 60mm) could further promote β-catenin nuclear translocation in osteocytes. The far field LIPUS osteocyte-CM (130mm group) caused the highest biological effect on (1) pre-osteoblasts migration (reflected by wound healing assay); (2) maturation of pre-osteoblasts: transition of cell proliferation into osteogenic differentiation (BrdU cell proliferation assay and ALP activity assay); and (3) matrix calcification (Alizarin red calcium nodule staining). / In part three study, the transducer diameter was reduced by half in order to draw the far field location closer to the transducer (i.e. from 130 mm to 30 mm). As the femoral shaft fractures of rats are located at around 40 mm beneath the skin, fractures were directly exposed to far field LIPUS transcutaneoulsy. It is a more clinically applicable approach than the method of physical separation (i.e. 130 mm separation between transducer and fractured limb). Femoral fractured SD rats were randomized into control, LT-Near30 (conventional transducer diameter, near field, I[subscript SATA] = 30 mW/cm²), ST-Far30 (small transducer, far field, I[subscript SATA] = 30 mW/cm²) and ST-Far150 (small transducer, far field, I[subscript SATA]=150 mW/cm²). Our results confirmed that the far field LIPUS emitted from the transducer diameter reduction setup (ST-Far30) could further facilitate fracture healing process by enhancing callus formation and mechanical properties. Our findings also indicated that fractures exposed to far field LIPUS with relatively higher intensity (150 mW/cm²) did not heal better. / In summary, our in vivo and in vitro findings reinforce each other to confirm the positive effects of far field LIPUS on promoting fracture healing. As far field LIPUS radiates a stable ultrasound beam, osteocytes inside the callus are triggered to secrete soluble factors to promote the osteogenic activities of osteoblastic cells. This contributes to the higher therapeutic effects of far field LIPUS on fracture healing. We also translated these findings to establish a clinically applicable LIPUS device, which directly radiates far field LIPUS to subcutaneous fracture site without any distance separation needed. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Fung, Chak Hei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 186-207). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.i / 中 文 摘 要 --- p.v / Publications --- p.ix / Acknowledgements --- p.xii / List of Abbreviations --- p.xiii / Index for Figures --- p.xvi / Index for Tables --- p.xviii / Chapter Chapter 1. --- Introduction and Literature Review --- p.1 / Chapter 1.1 --- Long Bone Fracture - A Growing Global Challenge --- p.2 / Chapter 1.2 --- Long-Bone Fracture - Current Management and Limitations --- p.5 / Chapter 1.3 --- Cellular Biology of Fracture Healing --- p.7 / Chapter 1.3.1 --- Stage 1: Inflammation --- p.7 / Chapter 1.3.2 --- Stage 2: Soft callus formation --- p.8 / Chapter 1.3.3 --- Stage 3: Hard callus formation --- p.9 / Chapter 1.3.4 --- Bone Remodeling --- p.10 / Chapter 1.4 --- Biophysical Stimulation to Bone --- p.13 / Chapter 1.5 --- Low-intensity Pulsed Ultrasound --- p.14 / Chapter 1.5.1 --- Application of LIPUS on Fracture Healing --- p.14 / Chapter 1.5.2 --- Physics of Ultrasound --- p.16 / Chapter 1.5.3 --- Ultrasound Parameters --- p.20 / Chapter 1.5.3.1 --- Ultrasound Frequency --- p.20 / Chapter 1.5.3.2 --- Duty Cycle --- p.22 / Chapter 1.5.3.3 --- Intensity --- p.22 / Chapter 1.5.3.4 --- Angle of Incidence --- p.24 / Chapter 1.5.3.5 --- Ultrasound Field --- p.25 / Chapter 1.5.4 --- Possible Mechanism of LIPUS on Tissue --- p.31 / Chapter 1.5.4.1 --- Thermal Effect --- p.31 / Chapter 1.5.4.2 --- Cavitation --- p.31 / Chapter 1.5.4.2 --- Acoustic Streaming --- p.32 / Chapter 1.5.4.3 --- Frequency Resonance Hypothesis --- p.32 / Chapter 1.5.4.4 --- Micromotion --- p.33 / Chapter 1.6 --- Possible Cellular and Molecular Mechanotransduction Mechanism of LIPUS --- p.34 / Chapter 1.6.1 --- Osteocyte: Potential Mechanosensor --- p.34 / Chapter 1.6.3 --- Osteocyte-osteoblast mechanotransduction --- p.39 / Chapter 1.7 --- Hypothesis --- p.39 / Chapter 1.8 --- Study Plan and Objectives --- p.40 / Chapter 1.8.1 --- Study Plan --- p.40 / Chapter 1.8.2 --- Objectives --- p.42 / Chapter Chapter 2. --- Characterization of Ultrasound Field Distances on Rat Fracture Model --- p.43 / Chapter 2.1 --- Introduction --- p.44 / Chapter 2.2 --- Material & Methods --- p.47 / Chapter 2.2.1 --- Closed Femoral Shaft Fracture Model in Rat --- p.47 / Chapter 2.2.2 --- Ultrasound Field Distances Setup --- p.51 / Chapter 2.2.3 --- Animal Grouping & LIPUS Treatment Protocol --- p.53 / Chapter 2.2.4 --- Assessments --- p.56 / Chapter 2.2.4.1 --- Radiological Analysis --- p.56 / Chapter 2.2.4.2 --- Micro-computed Tomography --- p.61 / Chapter 2.2.4.3 --- Histomorphometry --- p.64 / Chapter 2.2.4.4 --- Mechanical Testing --- p.66 / Chapter 2.2.4.5 --- Statistical Analysis --- p.66 / Chapter 2.3 --- Results --- p.68 / Chapter 2.3.1 --- Radiological Analysis --- p.71 / Chapter 2.3.2 --- MicroCT --- p.77 / Chapter 2.3.3 --- Histomorphometry --- p.82 / Chapter 2.3.4 --- Mechanical Testing --- p.85 / Chapter 2.4 --- Discussion --- p.87 / Chapter 2.4.1 --- Far Field LIPUS Enhances Mechanical Properties of Healing Callus --- p.88 / Chapter 2.4.2 --- Mid-near field and Near field LIPUS Enhances Woven Bone Formation --- p.90 / Chapter 2.4.3 --- The Biological Effects of LIPUS with Different Ultrasound Field Exposure --- p.94 / Chapter 2.5 --- Conclusion --- p.97 / Chapter Chapter 3. --- The Effect of Ultrasound Field Distances on Bone Cells --- p.100 / Chapter 3.1 --- Introduction --- p.101 / Chapter 3.2 --- Material & Methods --- p.102 / Chapter 3.2.1 --- Cell Culture --- p.102 / Chapter 3.2.2 --- Ultrasound Field Distances Setup & Treatment Protocol --- p.102 / Chapter 3.2.2 --- Immunostaining of β-catenin --- p.106 / Chapter 3.2.3 --- Wound Healing Assay --- p.109 / Chapter 3.2.4 --- BrdU Cell proliferation Assay --- p.111 / Chapter 3.2.5 --- Alkaline phosphatase activity assay --- p.112 / Chapter 3.2.6 --- Alizarin calcium nodule staining --- p.113 / Chapter 3.2.7 --- CM characterization - PGE₂ ELISA assay --- p.114 / Chapter 3.2.8 --- CM characterization - nitrite assay --- p.114 / Chapter 3.2.9 --- Statistical Analysis --- p.115 / Chapter 3.3 --- Results --- p.116 / Chapter 3.3.1 --- Immunostaining of β-catenin --- p.116 / Chapter 3.3.2 --- Wound healing assay --- p.119 / Chapter 3.3.3 --- BrdU Cell proliferation Assay --- p.119 / Chapter 3.3.4. --- Alkaline phosphatase activity assay --- p.122 / Chapter 3.3.5 --- Alizarin calcium nodule staining --- p.122 / Chapter 3.3.6. --- CM characterization - PGE₂ ELISA assay --- p.125 / Chapter 3.3.7 --- CM characterization - nitrite assay --- p.125 / Chapter 3.4 --- Discussion --- p.128 / Chapter 3.4.1 --- The Osteogenic Effect of Far Field LIPUS-Osteocyte Conditioned Medium --- p.128 / Chapter 3.4.2. --- Mechanisms of Mechanotransduction between Osteocyte and Osteoblast --- p.131 / Chapter 3.5 --- Conclusion --- p.136 / Chapter Chapter 4. --- Rat Fracture Exposed to Far Field LIPUS by Modulating Ultrasound Transducer Diameter --- p.139 / Chapter 4.1 --- Introduction --- p.140 / Chapter 4.2 --- Material & Methods --- p.143 / Chapter 4.2.1 --- Closed Femoral Shaft Fracture Model in Rat --- p.143 / Chapter 4.2.2 --- Ultrasound Field Distances Setup & Treatment Protocol --- p.143 / Chapter 4.2.3 --- Assessments --- p.148 / Chapter 4.2.3.1 --- Radiological Analysis --- p.148 / Chapter 4.2.3.2 --- Micro-computed Tomography --- p.148 / Chapter 4.2.3.3 --- Histomorphometry --- p.149 / Chapter 4.2.3.4 --- Mechanical Testing --- p.151 / Chapter 4.2.3.5 --- ex vivo Temperature Measurements --- p.151 / Chapter 4.2.3.6 --- Statistical Analysis --- p.151 / Chapter 4.3 --- Results --- p.152 / Chapter 4.3.1 --- Radiological Analysis --- p.154 / Chapter 4.3.2 --- MicroCT --- p.157 / Chapter 4.3.3 --- Histomorphometry --- p.160 / Chapter 4.3.4 --- Mechanical Testing --- p.166 / Chapter 4.3.5 --- ex vivo Temperature Measurement --- p.168 / Chapter 4.4 --- Discussion --- p.170 / Chapter 4.4.1 --- Far field LIPUS Setup by Transducer Diameter Modulation Enhanced Fracture Healing --- p.170 / Chapter 4.4.2 --- Fractures Exposed to Far Field LIPUS with Higher Intensity Did Not Heal Better --- p.174 / Chapter 4.4.3 --- Biphasic Effect of LIPUS Intensities on Fracture Healing --- p.176 / Chapter 4.5 --- Conclusion --- p.178 / Chapter Chapter 5. --- Conclusion --- p.179 / Chapter 5.1 --- Differential Biological Effects of Ultrasound Fields --- p.180 / Chapter 5.2 --- Far Field LIPUS exposure can be achieved by transducer diameter modulation --- p.181 / Chapter 5.3 --- Biphasic Effect of Ultrasound Intensities on Fracture Healing --- p.181 / Chapter 5.4 --- Mechanotransduction between Osteocyte and Osteoblastic cells --- p.182 / Chapter 5.5 --- Clinical Implications --- p.183 / Chapter 5.6 --- Future Investigations --- p.184 / Chapter 5.7 --- Limitations --- p.184 / Bibliography --- p.186 / Appendix --- p.208
232

Kunskaper hos sjuksköterskor och undersköterskor om sårbehandling inom kirurgisk verksamhet.

Norelius Schoeps, Lena, Tallberg, Anna-Britta January 2011 (has links)
Att ha ett sår är en belastning och påverkar människors vardag, oavsett om såret är akut efter ett olycksfall eller efter en operation, alternativt svårläkande som vid bensår, diabetesfotsår, trycksår eller maligna tumörsår. Syftet med studien var att undersöka kunskaper hos sjuksköterskor och undersköterskor om sårbehandling inom kirurgisk verksamhet. Metoden utgjordes av en enkätundersökning hos sjuksköterskor (n=56) och undersköterskor (n=38). Resultatet visar att sjuksköterskorna kände sig mer osäkra i sitt val av behandling av svårläkande sår jämfört med undersköterskorna. Kunskaperna om sårbehandling visar att skattade kunskaper inte motsvarar svaren på kunskapsfrågorna. Nitton av 56 sjuksköterskor och 15 av 37 undersköterskor hade genomgått någon form av sårutbildning. Undersköterskorna skattar sina kunskaper om sårbehandling högre än sjuksköterskorna och känner sig mer sällan osäkra i sitt val av behandling av svårläkande sår, jämfört med sjuksköterskorna. Det är också undersköterskorna som oftast utför såromläggningar på avdelningarna. Studien visar att det finns brister i kunskaperna om sårbehandling, hos både sjuksköterskor och undersköterskor och att mer utbildning behövs. / To have a wound is a burden and affect people's everyday lives, whether the wound is acute after an accident or after surgery or difficult healing of the ulcers, diabetic foot ulcers, pressure ulcers or a malignant wound. The purpose of this study was to investigate nurses' and nursing assistant’s knowledge of wound healing in surgical wards. The method was done by using a questionnaire survey among registered Nurses (RNs) (n = 56) and nursing assistants (NAs) (n = 38). The results show that the RNs felt more insecure in their choice of treatment of severe ulcer healing compared with the NAs. Knowledge of wound healing shows that the estimated knowledge does not correspond to the answers to knowledge questions. Of the RNs answered 51 of 56 and of the NAs answered 32 of 37 that they needed more education in wound care/treatment. NAs estimated their knowledge of wound care higher than the RNs and felt less insecure in their choice of treatment of wound healing, compared with the RNs. There are also the NAs who usually perform a change of dressing on the wards. The study shows that there are gaps in knowledge in wound care/treatment, with both RNs and NAs and that more education is needed.
233

Development of biocompatible multi-drug conjugated nanoparticles/smart polymer films for biomedicinal applications

Greenhalgh, Kerriann R 01 June 2007 (has links)
It has been reported by the American Burn Association that 4,000 people die every year due to burn injury. After survival of the initial trauma, the next major obstacle that must be overcome is combating bacterial infection, the primary cause of mortality for burn victims (Chapter 1). The polyacrylate nanoparticle drug delivery system was created to provide a water-based solution for delivery of highly lipophilic antimicrobials; such as N-thiolated β-lactams, however, with the success of this system for these antimicrobials, it was extended towards other, commercially-available water-soluble antimicrobials through acrylation of the drug monomers, including those with observed bacterial resistance (Chapter 2). Various antibiotics were incorporated into this polyacrylate nanoparticle delivery system by either encapsulation or covalent attachment, and the antibacterial activity was determined in vitro (Chapter 3). Since current treatment of burn wound infections calls for numerous antimicrobials in order to combat the vast array of microbes that may be present in the wound, a multi-drug conjugated nanoparticle system was constructed and analyzed for antibacterial activity against many pathogens commonly found in burn wounds (Chapter 4). In vitro antibacterial assays suggest that the nanoparticle delivery system rejuvenated the activity of penicillin-based antibiotics against formerly resistant microbes, such as methicillin-resistant Staphylococcus aureus. The multi-drug conjugated nanoparticle emulsion had the added benefit of forming a drug-conjugated polyacrylate polymer film through air-drying and polymer coalescence. Upon topical application to a skin abrasion in a mouse model, a protective barrier was created over the wound. This film exhibits mechanical properties similar to elastin, a pliant biological material, giving it the elasticity and flexibility required to move and interact with the wound in the same fashion as intact skin (Chapter 5). This film also permits diffusion of essential nutrients and small molecules (such as oxygen and water) required for wound healing. The emulsion was able to be combined with other biological materials, such as collage, to form a biocomposite material expressing the most optimal properties from each constituent (Chapter 6). In vitro cytotoxicity analysis (Chapter 7) and in vivo toxicity studies (Chapter 8) produced positive results indicating that the multi-drug conjugated nanoparticle emulsion is a promising new treatment for the burn wound and other topical skin and soft tissue infections.
234

Psychosocial Stress And Delayed Wound Healing: A Novel Approach To Increase Nursing Awareness And Knowledge

Knight, Elizabeth Dawn January 2015 (has links)
Background: Chronic wounds are a significant health problem in various populations. Psychosocial stress is a lifestyle factor that has been shown to directly influence wound healing. Current findings support roles for assessment and reduction of psychosocial stress in the comprehensive management of chronic wounds, however, a gap remains between current research and current clinical practice. Purpose: To develop a novel method by which to educate nurses about the effects of psychosocial stress on wound healing while incorporating state-of-the-art technology that is sensitive to the needs of individuals with various learning styles. Objectives: To review current literature documenting the relationship between chronic psychosocial distress and delayed wound healing to identify essential content to include in educational modules for nurses. To develop three educational modules for nurses in inpatient and outpatient settings that address the relationship between chronic psychosocial distress and delayed wound healing, and the effects of stress-reduction interventions in formats that meet the needs of different learning styles. To conduct a focus group discussion with nurse-participants regarding educational module content and delivery methods in order to evaluate and improve these educational modules. Methods: A series of literature reviews were performed between June, 2010 and October, 2013, using articles identified through searches using the databases PubMed and CINAHL. Essential content regarding psychosocial stress and its impact on wound healing was identified, and was used in the development of educational modules, designed to meet the basic needs of individuals with different learning styles. A purposive sample of nurses was recruited through the use of flyers, reviewed the educational modules online, and met for a focus group to discuss their experiences with these modules. Outcomes: A novel method was developed by which to deliver educational material to nurses about psychosocial stress and delayed wound healing. Participants were motivated to learn, had self-awareness of their preferred learning styles, and responded positively to this method of education delivery; they were able to articulate the basic concepts presented in the modules. These findings may be generalizable to a larger audience and may inform the development of future education-delivery approaches in this area.
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Klinikinė bakteriologinių tyrimų reikšmė nustatant potencialius nudegimo žaizdos infekcijos sukėlėjus / The clinical value of bacteriological tests determining potential burn wound infection-causing pathogens

Pilipaitytė, Loreta 11 June 2013 (has links)
Bakteriologinis nudegimo žaizdų tyrimas svarbus nustatant esamus potencialius patogenus, padeda diagnozuoti infekciją, leidžia įvertinti sepsio tikimybę, nustatyti tinkamą laiką žaizdos audinių rekonstrukcijai. Tačiau iki dabar tęsiasi diskusijos, kuris mėginio paėmimo metodas yra optimalus žaizdos mikroflorai arba infekcijai nustatyti. Lietuvoje toks tyrimas iki šiol nebuvo atliktas, o kitų šalių mokslininkų skelbiami rezultatai gana prieštaringi. Atlikto darbo metu tyrėme, kuris bakteriologinio tyrimo metodas (kiekybinis bei pusiau kiekybinis tepinėliai ar biopsija) yra kliniškai vertingiausias žaizdos mikrofloros stebėjimui ligos periodu, infekcijos patvirtinimui atsižvelgiant į klinikinius žaizdos pokyčius. Vienodas bakterijų rūšis tose pačiose žaizdose dažniausiai nustatė biopsija ir pusiau kiekybinis tepinėlis. Šių metodų bendras rezultatų sutapimas buvo labai geras. Abiem metodais nustatomo bakterijų kiekio koreliacija – vidutinė. Tačiau geriausiai rezultatai sutapo žaizdoje esant nedideliam bakterijų kiekiui. Esant klinikiniams žaizdos infekcijos požymiams reikšmingai dažniau bakterijos ir didesnis jų rūšių kiekis nustatytas biopsijos tiriamojoje medžiagoje. Biopsijos metodu reikšmingai dažniau nustatytas labai gausus (>105 KFV) bakterijų kiekis. Nudegimo žaizdų užteršimui bakterijomis stebėti, kai nėra infekcijos požymių, pusiau kiekybinis tepinėlio metodas yra tinkamiausias. Kliniškai nustatytą žaizdos infekciją geriausiai atspindi biopsijos tyrimo rezultatai. / Evaluation of microorganisms in burn wound is important not only in determining potential pathogens present, but also allows diagnosing an infection, evaluating possibility of sepsis, and determining the appropriate time for wound tissue reconstruction. However, there are still many discussions about the optimal wound sample taking method to determine wound microflora or infection, and the opinions about sample taking methods for identification of microorganisms are controversial. We have compared three methods (quantitative swab, semi-quantitative swab, biopsy) and determined significant differences. Similar species of bacteria in the same wounds were most frequently identified by biopsy and the semi-quantitative swab method. The general concordance of the results of these methods was very good. There was a medium correlation of the bacterial amount identified by these methods. However, there was the best concordance of the results in presence of a small amount of bacteria in a wound.In presence of clinical wound infection signs, bacteria and larger number of their species were significantly more frequently identified in the biopsy material. The biopsy method significantly more frequently identified a very large amount (>105 CFU) of bacteria. The semi-quantitative swab method is most appropriate to monitor burn wound contamination with bacteria when there are no infection signs. A clinically determined wound infection was best reflected by the results of biopsy.
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Investigation into the proteolytic activity in chronic wound fluid and development of a remediation strategy

Rayment, Erin Alexis January 2007 (has links)
Chronic ulcers are an important and costly medical issue, causing their sufferers a large amount of pain, immobility and decreased quality of life. The common pathology in these chronic wounds is often characterised by excessive proteolytic activity, leading to the degradation of both the extracellular matrix, as well as key factors critical to the ulcer's ability to heal. As matrix metalloproteinases (MMPs), a large family of zinc-dependent endopeptidases, have been shown to have increased activity in chronic wound fluid (CWF), it was hypothesised that this specific proteolytic activity was directly related to an ulcer's chronic nature. Although previous studies have identified elevated proteases in CWF, many have reported contradictory results and therefore the precise levels and species of MMPs in CWF are poorly understood. The studies reported herein demonstrate that MMP activity is significantly elevated in CWF compared with acute wound fluid (AWF). In particular, these studies demonstrate that this proteolytic activity can be specifically attributed to MMPs and not another class of proteases present in wound healing. Furthermore, it is shown that MMP-9 is the predominant protease responsible for matrix degradation by CWF and is an indicator of the clinical status of the wound itself. Moreover, MMP-9 can be inhibited with the bisphosphonate alendronate, in the form of a sodium salt, a functionalised analogue, and also tethered to a synthetic biocompatible hydrogel compromised of aqueous poly (2-hydroxy methacrylate) PHEMA synthesised in the presence of poly(ethylene glycol) (PEG). Together, these results highlight the potential use of a tethered MMP inhibitor as an improved ulcer treatment to inhibit protease activity in the wound fluid, while still allowing MMPs to remain active in the wound bed where they perform vital roles in the activation of growth-promoting agents and immune system regulation.
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Wound ventilation : a new concept for prevention of complications in cardiac surgery /

Persson, Mikael, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 6 uppsatser.
238

Stimulation of tendon repair by platelet concentrate, CDMP-2 and mechanical loading in animal models /

Virchenko, Olena, January 2007 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2007. / Härtill 6 uppsatser.
239

Local collagen-gentamicin for prevention of sternal wound infections /

Friberg, Örjan, January 2006 (has links)
Diss. (sammanfattning) Linköping : Univ., 2006. / Härtill 5 uppsatser.
240

Effect of hyaluronan-activation of CD44 on cell signaling and tumorigenesis /

Li, Lingli, January 2006 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2006. / Härtill 4 uppsatser.

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