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971.
Differentiation of fibroblasts into contractile, α‐smooth muscle actin (α‐SMA) expressing myofibroblasts depends on the action of the cytokine TGFβ in conjunction with mechanical tension. The goal of this study was to assess whether mechanical stress may play a role in activating TGFβ. Previous studies have shown that myofibroblasts secrete TGFβ1 as a large latent complex, consisting of the latency associated protein (LAP), the latent TGFβ1 binding protein (LTBP‐1) and TGFβ1. LTBP‐1 targets the small latent complex of LAP and TGFβ1 to the extracellular matrix (ECM), providing a stock of latent TGFβ1. To reveal the mechanisms triggering the release of active TGFβ1 from LAP and LTBP‐1, myofibroblasts were cultured on flexible silicone membranes for 3d before being subjected to unique 5% uniaxial stretch. After stress application we observed the course of TGFβ1 activation over 24 h by quantifying luciferase synthesis under the control of the TGFβ‐inducible PAI‐1 promoter. TGFβ activation showed two distinct peaks 1 h and 6 h after stretch. TGFβ1 mRNA levels were increased after 6 h as assessed by semi‐quantitative RT‐PCR. To further determine if rapidly activated TGFβ1 was released from ECM stores, we stretched myofibroblast‐derived ECM after cells have been removed by desoxycholate or EDTA treatment. Finally, we assessed the importance of the actin cytoskeleton in TGFβ1 activation by stretching Triton‐X‐100‐ and cytochalasin‐D‐treated myofibroblasts. Our results suggest that mechanical activation of TGFβ in myofibroblast culture requires cell activity and a functional cytoskeleton. 相似文献
972.
GM Verrall IA Hamilton JP Slavotinek RD Oakeshott AJ Spriggins PG Barnes GT Fon 《Journal of Science and Medicine in Sport》2005,8(1):77-84
Traumatic osteitis pubis is a non-specific entity that relates to chronic groin injury and has recently been described as being akin to a pubic bone stress injury. It is uncertain whether or not reduction of hip joint range of motion occurs in traumatic osteitis pubis. The purpose of this study was to establish whether there is a reduction of hip range of motion in athletes who have chronic groin injury diagnosed as pubic bone stress injury. A case-control study was performed whereby 89 Australian Rules footballers underwent, with clinical history unknown, clinical and MRI examination of the groin region. Clinical criteria (pain with tenderness) and MR-criteria (pubic bone marrow oedema) were used for diagnosis of pubic bone stress injury. End-range internal and external rotation hip motion was measured using a goniometer. Athletes with and without symptoms were compared, as were athletes with current symptoms with athletes who had recovered from their groin pain episode. Chronic groin injury was diagnosed in 47 athletes with 37 having pubic bone stress injury. Thirteen athletes had previous groin injury. A reduction of internal and external hip range of motion was demonstrated in athletes with pubic bone stress injury (p < 0.05) and in athletes who had current symptoms compared to those who had recovered from their groin pain episode (p < 0.05). A reduction in hip range of motion was evident in athletes with chronic groin injury diagnosed as pubic bone stress injury. There may be a role for increasing hip range of motion in rehabilitation. 相似文献
973.
目的 :巨颅伴皮层下海绵样囊肿性脑白质病 (MLC)是近来被证实的一种新的常染色体隐性遗传病 ,该病的可能病变基因被确定在染色体 2 2qtel上的 3 cM区域内 ,通过研究将病变基因的可能范围进一步缩小。方法 :收集 3 3个家庭中的 3 9例MLC病人 ,对其中能提供丰富遗传信息的 1 2例家庭成员 ,运用 7个微卫星标识和 4个单核苷酸多态性标识进行连锁分析和单倍体型分析。结果 :在重组值为 0 0 2下微卫星标识 3 55c1 8的最大两点LOD值是6 65;采用单倍体型分析进一步将位于 2 2qtel上的MLC病变基因的关键位置缩小在 2 50kb内。结论 :MLC病变基因位于 2 2qtel上 2 50kb内 ,有 4个候选基因被考虑。另外 ,由于其中一个家庭成员存在遗传异质性 ,故考虑MLC可能存在第二个病变基因位点。 相似文献
974.
目的:观察牙本质陶瓷粉(Ceramic Dentin Powder;CDP),CDP复合转化生长因子(Transforming growth factors-TGF-β1(CDP/TGF-β1)对大鼠修复性牙本质形成的作用。方法:牙本质粉煅烧后与TGF-β1复合,用SD大鼠牙作直接盖髓实验,并用组织学方法评价材料对修复性牙本质形成的作用。结果:术后14d,CDP组:穿刺下方成牙本质细胞的正常排列消失,周围有炎细胞浸润;CDP/TGF-β1组;穿髓孔周围见成纤维细胞增殖,呈团块状包绕穿髓孔。术后28d,CDP组:穿髓下方可见少量修复性牙本质团块形成;CDP/TGF-β1组;在成纤维细胞下方可大量修复性牙本质形成;结论:CDP/TGF-β1能控制炎症的蔓延,促进大鼠牙体,牙髓组织修复。 相似文献
975.
P45
Microbiological culture analysis of the tongue microflora in subjects with and without halitosis
Objective Determination of the microflora present on the tongue dorsum of subjects with and without halitosis using conventional microbiological culture methods.
Methods Twenty-one halitosis and 20 control patients were recruited using a strict clinical protocol. Samples were collected from the posterior dorsum of the tongue using a sterile brush. Each sample was vortex mixed for 30 s and serial 10-fold dilutions to 10−7 were carried out. Samples were plated onto fastidious anaerobe agar (FAA) and FAA enriched with vancomycin. These were incubated under anaerobic conditions for 10 days at 37°C. Strict anaerobes were identified by metronidazole sensitivity and bacteria were identified to genus level by a combination of colony morphology, Gram staining and biochemical and enzymatic tests (rapid ID 32 A).
Results The predominant species in test and control groups were Veillonella and Prevotella . Greater species diversity was found in the halitosis samples compared to controls. The halitosis samples contained a larger number of unidentifiable gram-negative rods, gram positive rods and gram negative coccobacilli.
Conclusions There was no obvious association between halitosis and any specific bacterial genus. The increased species diversity found in halitosis samples suggests that halitosis may be the result of complex interactions between several bacterial species. The role of uncultivable bacteria may also be important in contributing to this process. 相似文献
Methods Twenty-one halitosis and 20 control patients were recruited using a strict clinical protocol. Samples were collected from the posterior dorsum of the tongue using a sterile brush. Each sample was vortex mixed for 30 s and serial 10-fold dilutions to 10
Results The predominant species in test and control groups were Veillonella and Prevotella . Greater species diversity was found in the halitosis samples compared to controls. The halitosis samples contained a larger number of unidentifiable gram-negative rods, gram positive rods and gram negative coccobacilli.
Conclusions There was no obvious association between halitosis and any specific bacterial genus. The increased species diversity found in halitosis samples suggests that halitosis may be the result of complex interactions between several bacterial species. The role of uncultivable bacteria may also be important in contributing to this process. 相似文献
976.
目的:观察牙本质陶瓷粉(ceramic dentin powder,CDP)、复合转化生长因子(transforming growth factors-TGF-β1);复合非胶原蛋白(noncollagenous proteins,NCPs)及全复合后对修复性牙本质形成的作用。方法:用SD大鼠牙作直接盖髓实验,并用组织学方法评价每组材料对修复性牙本质形成的效果。结果:各组材料在不同时间对修复牙本质促进作用不同,实验组的作用明显优于对照组,实验组之间未见明显差异。结论:TGF-β1、NCPs对大鼠牙髓组织修复有明显的促进作用。 相似文献
977.
Despite the many journal articles and reviews that have been published regarding the treatment of trauma to teeth, the endodontic management of these injuries is often still not fully understood. The purpose of this review is to establish clear and up-to-date guidelines for practitioners who are faced with treating dental injuries on a day-to-day basis, based on an assessment of current available scientific information relating to the endodontic management of these injuries.
Treatment is discussed under the headings: infractions, uncomplicated crown fractures, complicated crown fractures, crown-root fractures, root fractures, luxation injuries, avulsion, root resorption, pulp canal obliteration and open-apex teeth. Emphasis is placed on the treatment of traumatized immature teeth where maintenance of pulp blood supply is important to encourage continued development of the root system. Only the treatment of traumatized permanent anterior teeth is reviewed.
Information contained in this article is based on a review of the literature on dental trauma which involved a MEDLINE search using the key words "dental trauma" and the individual topics listed above. The guidelines produced by the International Association of Dental Traumatology, the American Academy of Pediatric Dentistry and the American Association of Endodontists were also reviewed and the recommendations contained in this paper are in concert with the major recommendations of these bodies. 相似文献
Treatment is discussed under the headings: infractions, uncomplicated crown fractures, complicated crown fractures, crown-root fractures, root fractures, luxation injuries, avulsion, root resorption, pulp canal obliteration and open-apex teeth. Emphasis is placed on the treatment of traumatized immature teeth where maintenance of pulp blood supply is important to encourage continued development of the root system. Only the treatment of traumatized permanent anterior teeth is reviewed.
Information contained in this article is based on a review of the literature on dental trauma which involved a MEDLINE search using the key words "dental trauma" and the individual topics listed above. The guidelines produced by the International Association of Dental Traumatology, the American Academy of Pediatric Dentistry and the American Association of Endodontists were also reviewed and the recommendations contained in this paper are in concert with the major recommendations of these bodies. 相似文献
978.
979.
980.
An Wouters Bea Pauwels Filip Lardon Greet GO Pattyn Hilde AJ Lambrechts Marc Baay Paul Meijnders Jan B Vermorken 《BMC cancer》2010,10(1):441