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991.
992.

Background

Autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis represent the three major autoimmune liver diseases (AILDs). Their management is highly specialized, requires a multidisciplinary approach and often relies on expensive, orphan drugs. Unfortunately, their treatment is often unsatisfactory, and the care pathway heterogeneous across different centers. Disease-specific clinical outcome indicators (COIs) able to evaluate the whole cycle of care are needed to assist both clinicians and administrators in improving quality and value of care. Aim of our study was to generate a set of COIs for the three AILDs. We then prospectively validated these indicators based on a series of consecutive patients recruited at three tertiary clinical centers in Lombardy, Italy.

Methods

In phase I using a Delphi method and a RAND 9-point appropriateness scale a set of COIs was generated. In phase II the indicators were applied in a real-life dataset.

Results

Two-hundred fourteen patients were enrolled and followed-up for a median time of 54 months and the above COIs were recorded using a web-based electronic medical record program. The COIs were easy to collect in the clinical practice environment and their values compared well with the available natural history studies.

Conclusions

We have generated a comprehensive set of COIs which sequentially capture different clinical outcome of the three AILDs explored. These indicators represent a critical tool to implement a value-based approach to patients with these conditions, to monitor, compare and improve quality through benchmarking of clinical performance and to assess the significance of novel drugs and technologies. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.  相似文献   
993.
为进一步提高羊骨酶解液的营养价值和生物利用度,探讨乳酸菌发酵对钙离子释放、短肽形成以及酶解液抗氧化活性的影响。首先从7株乳酸菌中筛选出了产蛋白酶能力最强的植物乳杆菌,接种羊骨酶解液,以发酵液中Ca~(2+)浓度为指标,响应面法优化得到发酵工艺:酶解液中添加1%的麦芽糖,调节起始pH为5.5,以4%接种量接种驯化好的植物乳杆菌,37℃摇床发酵14 h。发酵过程中,植物乳杆菌活菌数与Ca~(2+)含量(R=0.495,P0.01)和短肽得率(R=0.655,P0.01)呈极显著正相关,而多肽生成量与短肽得率呈负相关(R=–0.013)。发酵液中的Ca~(2+)浓度(P0.05)、水解度(P0.01)、短肽得率(P0.01)、羟脯氨酸含量(P0.01)均显著高于酶解液(P0.01),植物乳杆菌活菌数达到94.6×10~8 CFU/m L。发酵还可使酶解液对DPPH、·OH、O_2~-·三种自由基的清除能力显著提高(P0.01,P0.05)。综上所述,以植物乳杆菌发酵羊骨酶解液可进一步促进骨钙的转化和胶原短肽的生成并显著提高其体外抗氧化能力,短肽和Ca~(2+)反过来促进植物乳杆菌的繁殖,增强了酶解液的益生功能,乳酸菌产生的维生素、胞外多糖等物质使羊骨酶解液更富营养。  相似文献   
994.
HSPB8 is a member of ubiquitous small heat shock protein (sHSP) family, whose expression is induced in response to a wide variety of unfavorable physiological and environmental conditions. Investigation of HSPB8 structure indicated that HSPB8 belongs to the group of so-called intrinsically disordered proteins and possesses a highly flexible structure. Unlike most other sHSPs, HSPB8 tends to form small-molecular-mass oligomers and exhibits substrate-dependent chaperone activity. In cooperation with BAG3, the chaperone activity of HSPB8 was reported to be involved in the delivery of misfolded proteins to the autophagy machinery. Through this way, HSPB8 interferes with pathological processes leading to neurodegenerative diseases. Accordingly, published studies have identified genetic links between mutations of HSPB8 and some kind of neuromuscular diseases, further supporting its important role in neurodegenerative disorders. In addition to their anti-aggregation properties, HSPB8 is indicated to interact with a wide range of client proteins, modulating their maturations and activities, and therefore, regulates a large repertoire of cellular functions, including apoptosis, proliferation, inflammation and etc. As a result, HSPB8 has key roles in cancer biology, autoimmune diseases, cardiac diseases and cerebral vascular diseases.  相似文献   
995.
骨癌痛(BCP)是恶性肿瘤患者最常见的疼痛之一,严重影响患者的生活质量。BCP的分子作用机制和新药研发都迫在眉睫。2-溴棕榈酸(2-BP)作为一种蛋白质棕榈化抑制剂在病理性疼痛中有镇痛效果,而在骨癌痛中作用仍不清楚。酸敏感离子通道3型(ASIC3),作为一个重要的疼痛因子能否受到2-BP的调控也未知。为了检测2-BP在骨癌痛中的作用,并研究其对背根神经节(DRG)中ASIC3的调控,本文开展了相关工作。1)首先建立BCP大鼠模型,将大鼠乳腺癌细胞(MRMT-1)注射入雌大鼠胫骨骨髓腔内,21 d后通过X射线和机械痛检测,发现与假性手术组相比,BCP模型大鼠的胫骨被破坏;同时,BCP组大鼠的机械疼痛值明显上升(假性手术组PWT vs. BCP PWT:16.1 ± 1.5 vs. 5.3 ± 1.5; P<0.01);表明大鼠乳腺癌骨转移疼痛模型成功构建。2)蛋白质免疫印迹检测结果显示,与正常和假性手术组相比,BCP大鼠L4-L6 DRG中酸敏感离子通道3蛋白表达上调(0.63 ± 0.03, 0.64 ± 0.1 和 1.07 ± 0.05)。3)在术后第21 d,给BCP大鼠腹腔注射2-BP,发现给药组BCP大鼠的机械疼痛值下调 (6 h后,PWT 对照 vs. PWT 2-BP: 6.9 ± 2.0 vs. 10.8 ± 1.6, P<0.01),表明2-BP在骨癌痛模型大鼠中具有镇痛作用。4)蛋白质免疫印迹结果显示,与给药前相比,2-BP处理后降低了BCP大鼠L4-L6 DRG中膜上ASIC3蛋白的表达(1.05 ± 0.13, 0.66 ± 0.12)。同时,在ASIC3介导的酸痛模型中,2-BP给药降低大鼠震颤的次数(对照组为27 ± 1.8次,2-BP组为10 ± 1.5次),表明2-BP给药阻断ASIC3介导的酸痛。5)在ASIC3转染的SH-SY5Y细胞中,与对照相比,2-BP给药后明显降低膜上ASIC3蛋白表达量(1.0 ± 0.2, 0.58 ± 0.10)。这些结果表明,2-BP在骨癌痛中具有镇痛作用,其镇痛机制涉及到调控背根神经节中膜上酸敏感离子通道3的表达。  相似文献   
996.
Background: There is lack of further observations on the microstructure and material property of callus during bone defect healing and the relationships between callus properties and the mechanical strength. Methods: Femur bone defect model was created in rabbits and harvested CT data to reconstruct finite element models at 1 and 2 months. Three types of assumed finite element models were compared to study the callus properties, which assumed the material elastic property as heterogeneous (R-model), homogenous (H-model) or did not change from 1 to 2 months (U-model). Results: The apparent elastic moduli increased at 2 months (from 355.58 ± 132.67 to 1139.30 ± 967.43 MPa) in R-models. But there was no significant difference in apparent elastic moduli between R-models (355.58 ± 132.67 and 1139.30 ± 967.43 MPa) and H-models (344.79 ± 138.73 and 1001.52 ± 692.12 MPa) in 1 and 2 months. A significant difference of apparent elastic moduli was found between the R-model (1139.30 ± 967.43 MPa) and U-model group (207.15 ± 64.60 MPa) in 2 months. Conclusions: This study showed that the callus structure stability remodeled overtime to achieve a more effective structure, while the material quality of callus tissue is a very important factor for callus strength. At the meantime, this study showed an evidence that the material heterogeneity maybe not as important as it is in bone fracture model.  相似文献   
997.
998.
999.
Recent ancient DNA (aDNA) studies of human pathogens have provided invaluable insights into their evolutionary history and prevalence in space and time. Most of these studies were based on DNA extracted from teeth or postcranial bones. In contrast, no pathogen DNA has been reported from the petrous bone which has become the most desired skeletal element in ancient DNA research due to its high endogenous DNA content. To compare the potential for pathogenic aDNA retrieval from teeth and petrous bones, we sampled these elements from five ancient skeletons, previously shown to be carrying Yersinia pestis. Based on shotgun sequencing data, four of these five plague victims showed clearly detectable levels of Y. pestis DNA in the teeth, whereas all the petrous bones failed to produce Y. pestis DNA above baseline levels. A broader comparative metagenomic analysis of teeth and petrous bones from 10 historical skeletons corroborated these results, showing a much higher microbial diversity in teeth than petrous bones, including pathogenic and oral microbial taxa. Our results imply that although petrous bones are highly valuable for ancient genomic analyses as an excellent source of endogenous DNA, the metagenomic potential of these dense skeletal elements is highly limited. This trade‐off must be considered when designing the sampling strategy for an aDNA project.  相似文献   
1000.
A method is presented to find orthotropic elastic symmetries and constants directly from the elastic coefficients in the overall stiffness matrix of trabecular bone test specimens. Contrary to earlier developed techniques, this method does not require pure orthotropic behavior or additional fabric measurements. The method uses high-resolution computer reconstructions of trabecular bone specimens as input for large-scale FE-analyses to determine all the 21 elastic coefficients in the overall stiffness matrix of the specimen, using a direct mechanics approach. An optimization procedure is then used to find the coordinate transformation that yields the best orthotropic representation of this matrix. The method is illustrated here relative to two trabecular bone specimens. The techniques developed here can be used to obtain a complete characterization of the mechanical properties of trabecular architecture. With the development of in vivo reconstruction techniques, even in vivo measurements will be possible.  相似文献   
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