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11.
背景:组织工程是一个多学科研究的交叉学科,其目标是使人体损伤的组织和器官再生,通过这种假设,几乎所有的动物组织都可以在实验室进行培养。一般的方法是从需要移植的患者身上提取干细胞,在一定的支持条件下允许其生长、增殖、生产为可替换的组织。另一方面,寻找细胞能够互相联结并形成分层结构的合适的支持条件,如基质或支架等非常必要。目前用于烧烫伤治疗的材料有很多种,如胶原,透明质酸、纤维蛋白和聚乳酸及其共聚物。
目的:讨论以新型的生物材料自体血浆为支架对自体成纤维细胞和角质化细胞生长、扩张、增殖的影响。
设计:建立一种真皮再生的方法,将自体成纤维细胞浸于人血浆基质中,排除各种影响样本安全性和排斥反应的问题,应用同样的方法在新的真皮上获取角质化细胞。
时间及地点:实验于2008年在意大利曼多瓦C. Poma医院动物工厂完成。
材料:人角质化细胞和成纤维细胞取自1例58岁乳房切除患者的皮肤碎片。实验得到C. Poma医院独立伦理委员会批准,患者知情同意。
方法:从自体活组织皮肤样本中分离人角质化细胞和成纤维细胞,置于培养瓶中增殖,随后将自体血浆作为皮肤移植形成构造的支架,免疫和免疫组织化学特征显示与正常皮肤相似。
主要观察指标:将血浆样本用甲醛固定,埋入石蜡,苏木精-伊红染色,用显微镜进行细胞计数。所有样本均经免疫组织化学评估。
结果:在血浆基质上获得了多层规则形状的角质化细胞和成纤维细胞,基底膜的形成说明自体血浆是角质化细胞和成纤维细胞的生长、分化、扩展的良好支架,真皮和表皮细胞联结重建皮肤移植与正常皮肤无异。
结论:血浆作为角质化细胞和成纤维细胞分化、扩展的支架表现出良好的性能,同时实验还特别发现成纤维细胞浓缩血浆可以暂时替代皮肤,也是角质化细胞生长的强有力的支架。此外血浆还具有廉价,易于制备等优点。自体角质化细胞和成纤维细胞及自体血浆的应用,可以避免血种类型的免疫排斥反应。这种治疗方法给有慢性缺损并且需要连续移植的患者带来了希望。
doi:10.3969/j.issn.1673-8225.2009.47.001 相似文献
12.
A Federico C Battisti M P Eusebi N de Stefano A Malandrini M Mondelli N Volpi 《European neurology》1991,31(6):366-371
We report the clinical, neurophysiological (comprehending electromyography, nerve conduction velocities, and multimodal evoked potentials), histological study of the nerve and muscle and the effect of vitamin E supplement in a 32-year-old case with chronic vitamin E deficiency subsequent to acquired intestinal malabsorption. An early diagnosis for an early treatment is essential in preventing severe neurological deterioration. 相似文献
13.
Alessia Pascale Marialaura Amadio Stefano Govoni Fiorenzo Battaini 《Pharmacological research》2007,55(6):560-569
The brain represents the primary centre for the regulation and control of all our body activities, receiving and interpreting sensory impulses and transmitting information to the periphery. Most importantly, it is also the seat of consciousness, thought, emotion and especially memory, being in fact able to encode, store and recall any information. Memory is really what makes possible so many of our complex cognitive functions, including communication and learning, and surely without memory, life would lose all of its glamour and purpose. Age-associated mental impairment can range in severity from forgetfulness at the border with pathology to dementia, such as in Alzheimer's disease. In recent years, one of the most relevant observations of research on brain aging relates to data indicating that age-related cognitive decline is not only due to neuronal loss, as previously thought; instead, scientists now believe that age-associated functional changes have more to do with the dysfunctions occurring over time. Within this context a prominent role is certainly played by signal transduction cascades which guarantee neuronal cell to elaborate coordinated responses to the multiple signals coming from the outside and to adapt itself to the environmental changes and requests. This review will focus the attention on protein kinase C pathway, with a particular interest on its activation process, and on the role of protein-lipid and protein-protein interactions to selectively localize the cellular responses. Furthermore, information is emerging and will be discussed on the possibility of mRNA stabilization through PKC activation. This review will also approach the issue on how alterations of these molecular cascades may have implications in physiological and pathological brain aging, such as Alzheimer's disease. 相似文献
14.
15.
Stefano Di Domenico Giulio Bovio Maximiliano Gelli Ferruccio Ravazzoni Enzo Andorno Damiano Cottalasso Umberto Valente 《BMC surgery》2007,7(1):18
Background
Liver transplantation in presence of diffuse portal vein thrombosis is possible by using caval blood as portal inflow, through cavo-portal transposition. However, clinical results are heterogeneous and experimental studies are needed, but similar hemodynamic conditions are difficult to obtain, especially in small animals. Herein we describe a new simple model of cavo-portal transposition in rat. 相似文献16.
Monica Conciatori Christopher J Stodgell Susan L Hyman Melanie O'Bara Roberto Militerni Carmela Bravaccio Simona Trillo Francesco Montecchi Cindy Schneider Raun Melmed Maurizio Elia Lori Crawford Sarah J Spence Lucianna Muscarella Vito Guarnieri Leonardo D'Agruma Alessandro Quattrone Leopoldo Zelante Daniel Rabinowitz Tiziana Pascucci Stefano Puglisi-Allegra Karl-Ludvig Reichelt Patricia M Rodier Antonio M Persico 《Neuropsychopharmacology》2004,55(4):413-419
BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference. 相似文献
17.
Ibrahim Fikry Abdelwahab Stefano Bianchi Carlo Martinoli Michael Klein George Hermann 《Journal l'Association canadienne des radiologistes》2006,57(5):278-286
Tuberculosis involving the soft tissue from adjacent bone or joint is well recognized. However, primary tuberculous pyomyositis, tuberculous bursitis, and tuberculous tenosynovitis are rare entities constituting 1% of skeletal tuberculosis. Tuberculous tenosynovitis involves most commonly the tendon sheaths of the hand and wrist, and tuberculous bursitis occurs most commonly around the hip. The greater trochanteric bursa and the greater trochanter are the most frequent sites of tuberculous bursitis. Cases of primary tuberculous pyomyositis and tenosynovitis of the tendons of the ankle and foot are seldom reported in the radiology literature. All imaging modalities-plain radiography, bone scan, computed tomography, and magnetic resonance imaging (MRI)--provide information that is helpful in determining therapy. MRI in particular, with its multiplanar capabilities and superb contrast of soft tissue, can demonstrate the extent of the soft tissue mass and access the adjacent bones and joints. However, MRI has no diagnostic specificity in regard to tuberculosis, and in nonendemic areas, biopsy is strongly recommended. All patients in this review were permanent residents of North America or Western Europe and were immunocompetent. Examples of atypical presentations of the above entities are demonstrated. 相似文献
18.
Stefano Elia Gianluca Guggino Davide Mineo Gianluca Vanni Antonello Gatti Tommaso Claudio Mineo 《European journal of cardio-thoracic surgery》2005,28(2):312-7; discussion 317
OBJECTIVE: To verify the feasibility and compare the results of thoracoscopic sympathectomy under local anaesthesia (LA) and spontaneous breathing vs. general anaesthesia (GA) with one-lung ventilation. METHODS: Two groups of consecutive patients underwent one stage bilateral T2-T3 thoracoscopic sympathectomy under LA (n=15) and GA (n=30) by the same surgical team for treatment of primary palmar hyperhidrosis. The groups were homogeneous for relevant demographic, physiological and clinical data, including pulmonary function. In both groups, patient's satisfaction was evaluated 24h after surgery by a simple interview and scored into five grades (1=very poor to 5=excellent), while quality of life (QOL) was evaluated by SF-36 and Nottingham's Health Profile questionnaires before and 6 months after surgery. A cost comparison between groups concerning devices, drugs, global in operating room time, medical personnel and hospital stay was also carried out. RESULTS: No operative mortality was recorded. The overall in operating room time for the whole bilateral procedure under LA was 63.55+/-10.58 vs. 86.05+/-5.75 under GA (P<0.01) and temperature increased in all patients from a baseline of 25.42+/-0.56 up to 32.15+/-0.84 degrees C. All patients undergone LA were discharged the same day after a chest roentgenogram and a short stay in the outpatient clinic. Among them three patients (20%) experienced a minimal (<30%) pneumothorax that required no treatment, while five (33.3%) had a trunk compensatory sweating that spontaneously resolved on the long run. Patients undergoing GA were discharged after a mean stay of 1.38+/-0.6 days. Among these, eight (26.6%) had prolonged trunk compensatory sweating that did not persist longer than 3 months. At a follow-up of 7.16+/-2.97 months, QOL was significantly improved with no difference between groups. The overall rate of satisfaction was greater in the LA group (P<0.05). CONCLUSIONS: In our study, awake one stage bilateral thoracoscopic sympathectomy for palmar hyperhidrosis could be safely and effectively performed as an outpatient procedure in patients refusing GA. Postoperative quality of life was equal to that in patients undergone the same procedure under GA, while patient satisfaction was better and cost were significantly reduced. 相似文献
19.
Stefano Sdringola Catalin Loghin Fernando Boccalandro K Lance Gould 《Journal of nuclear medicine》2006,47(1):59-67
Changes in regional myocardial perfusion throughout the entire coronary vascular tree, as opposed to changes in the worst regional perfusion defect, have not been described during long-term regression or progression of coronary artery disease (CAD) or related to clinical outcomes. METHODS: Four-hundred nine patients with CAD undergoing dipyridamole PET at baseline and after 2.6 +/- 1.4 y were followed over 5 more years for coronary events. PET images were objectively quantified by automated software for changes in severity of the (i) baseline worst quadrant, indicating the worst flow-limiting stenosis at baseline PET; (ii) follow-up worst quadrant, indicating the worst stenosis on follow-up PET; and (iii) maximal change quadrant, indicating the largest change of any same quadrant pair from baseline-to-follow-up images. RESULTS: At follow-up PET, new regional perfusion defects were seen in 40% of patients. In 77% of patients, the greatest change was in a quadrant different from the worst baseline defect. The maximal change quadrant improved in 70% of patients on intense lifestyle and pharmacologic lipid treatment, in 48% on moderate treatment, and in 39% on poor treatment (P < 0.0001). Combined quadrant changes integrated throughout the heart independently predicted cardiovascular events at long-term follow-up. In contrast, changes of any single baseline-to-follow-up quadrant pair did not. CONCLUSION: By PET, 77% of patients with CAD had the greatest perfusion changes in areas different from the baseline worst perfusion defect and 40% had new perfusion defects. Changes in perfusion defects throughout the entire coronary vascular tree predicted coronary events, whereas changes in the worst flow-limiting stenosis at baseline or in any one segment of myocardium did not. To our knowledge, these data provide the first direct evidence on mechanisms for disproportionately greater reduction in cardiac events than changes in single stenosis severity with lipid treatment. 相似文献
20.
Giuseppina Di Stefano Luigi Fiume Michele Baglioni Corrado Busi Pasquale Chieco Felix Kratz Alessandro Mattioli 《European journal of pharmaceutical sciences》2007,30(2):136-142
Several attempts have been made to enhance doxorubicin (DOXO) concentrations in tumour cells by drug conjugation with human albumin (HSA). HSA-DOXO has the drawback of causing DOXO accumulation in spleen and bone marrow, with a consequent leucopoenia not produced when lactose molecules are coupled to the carrier protein. In the present experiments we demonstrated that the effect of HSA lactosamination is not a consequence of a more rapid disappearance from the bloodstream of the lactosaminated conjugate (L-HSA-DOXO), which is rapidly internalized by the liver through the asialoglycoprotein receptor, but is due to a hindered uptake by spleen and bone marrow cells caused by the coupled lactose molecules. Experiments in vitro showed that HSA-DOXO produced an inhibition of murine macrophage proliferation not caused by L-HSA-DOXO. This result can be explained by higher amounts of the former conjugate entering in these cells and suggests macrophages as the cell type responsible for the spleen and bone marrow internalization of HSA-DOXO hindered by lactose coupling. Importantly, lactosamination of HSA did not reduce the marked uptake of HSA-DOXO by chemically induced rat hepatocellular carcinoma. L-HSA-DOXO, by avoiding DOXO accumulation in bone marrow is an attractive candidate for clinical trials against tumors which were found to actively internalize this conjugate in laboratory animals, such as hepatocellular carcinoma. 相似文献