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1.
目的 鉴定当地民间应用普遍的野生药用真菌,并探讨其治疗肿瘤的作用机制。方法 采用形态学和分子生物学方法对一株采自定陶仿山野生药用真菌进行鉴定,确定为硬皮马勃。通过文献检索收集硬皮马勃化学成分,利用PubChem软件和TCMSP、GCS数据库得到化学成分结构信息及其药用动力学参数和相关靶点分析,通过SysDT和WES系统鉴定潜在化学成分靶点,利用CTD数据库获得靶点功能,将潜在化合物和肿瘤相关靶点导入Cytoscape3.8.0软件构建分子-靶标网络。应用DAVID数据库对肿瘤相关靶点进行GO和KEGG富集分析,揭示有关活性成分靶点所涉及的生物学过程和通路,将肿瘤相关靶点和通路导入Cytoscape3.8.0软件构建靶点-通路网络。结果 从文献中获得硬皮马勃的化学成分59个,通过ADME计算系统筛选出5个潜在活性的化合物即活性成分,预测到38个靶点,其中与肿瘤相关靶点16个。这些活性成分主要通过Toll-like receptor、PI3K-AKT、MAPK和NF-kappa B等通路参与免疫应答,抑制肿瘤细胞生长、增殖,促进其凋亡。结论 表明硬皮马勃治疗肿瘤具有多靶点、多途径协同作用的特点,并通过多层次效应达到治疗肿瘤的效果。本研究为更好理解硬皮马勃作用肿瘤的机制和肿瘤药物开发提供理论依据。  相似文献   
2.
Purpose. To estimate disease activity in patients with systemic sclerosis using contrast-enhanced MRI of the skin. Material and Methods. In a pre-study, sequences of a low-field (0.2 T) scanner (Artoscan, Esaote, Genova, Italy) were optimized for detection of intravenous contrast (0.1 mmol/l Gd-DTPA) in six patients with the autoimmune disease systemic scleroderma. Based on the results of the pre-study, 17 patients with scleroderma (7 sclerotic/10 active inflammatory disease) were scanned using gradient-spoiled 3D GRE sequences (FA 90 °, TR 100 ms, TE 18 ms), which had been established as most sensitive for intravenous contrast. Contrast enhancement of the skin was determined quantitatively by contrast-to-noise ratios (CNR), comparing post- to pre-contrast and dynamic scans (for 6 min, 1 acquisition/min). Patients in the chronic state with sclerodactylia and active inflammation of the hands were considered separately and compared to a control group (n = 10) matched according to age. Results. CNR increase after intravenous contrast was significantly higher in patients with active disease (86 ± 16 % increase) than sclerosing disease (29 ± 3 %, p < 0.05) and the control group (4 ± 2 %, p < 0.05). The dynamic examination showed a significantly slower decrease after the peak rise in the first minute in patients with active disease (CNR 15.4 ± 0.7 to 14.2 ± 1.4) than in those with chronic disease (14.1 ± 0.5 to 11.3 ± 0.9, p < 0.05). Discussion. Capillary leakage is the most likely explanation for the increased enhancement in patients with active scleroderma. Using sequences optimized for contrast detection, disease activity in the course of scleroderma and response to therapy can be determined by MRI in the future.   相似文献   
3.
Summary Predictors of survival were determined in 171 patients with systemic sclerosis by univariate analysis, and the Cox proportional hazards model using both cross sectional data at entry into the follow-up and time-dependent follow-up data. Clinical and laboratory data were evaluated from 1982 to the end of 1993. The presence of diffuse scleroderma, kidney and cardiac involvements were unfavourable prognostic signs in both the univariate analysis, and the Cox proportional hazards models. The Cox model, using the variables detected at study entry, indicated that pericarditis, and anaemia were bad prognostic signs. Analysis with time dependent data has not been reported in systemic sclerosis. The appearance of pigmentation disturbances, anaemia, and respiratory failure during the follow-up also caused a poor prognosis of the disease by the Cox model. In the stepwise selection models, diffuse scleroderma, internal organ manifestations including renal, and cardiac involvements were predominantly selected as the most unfavourable factors for survival. As to the extent of skin involvement and internal organ manifestations, the general behaviour of the disease seems to be similar throughout the world. The early appearance of pericarditis and pigmentation disturbances at study entry are bad prognostic signs.This work was supported by the Hungarian Ministry of Health and Social Welfare and by the National Foundation for Scientific Research.  相似文献   
4.
Three-dimensionally localized proton-decoupled phosphorus-31 magnetic resonance (MR) spectroscopy of skeletal and cardiac muscle was performed in six patients with systemic sclerosis. Cardiac (n = 9) and skeletal (n = 6) spectra were also obtained in healthy volunteers. Metabolite ratios and intracellular pH were determined from the spectra of skeletal and cardiac muscle. The phosphocreatine-to-adenosine triphosphate ratio was normal for both skeletal and cardiac muscle in patients with systemic sclerosis. The pH values of skeletal muscle were similar in patients and control subjects (7.13 ± 0.02 vs 7.12 ± 0.01, respectively). In skeletal muscle, the inorganic phosphate-to-phosphocreatine ratio in patients was increased relative to that of control subjects (0.106 ± 0.014 vs 0.086 ± 0.006, respectively; P =.02). P-31 MR spectroscopy showed no abnormalities in the myocardium of patients with systemic sclerosis. Assessment of the inorganic phosphate-to-phosphocreatine ratio in peripheral skeletal muscle may be helpful for assessing disease activity.  相似文献   
5.
Summary A long-term follow-up of two patients with scleroderma (SS) who developed a polyarthritis with bilateral femoral head osteonecrosis is reported. The severe parallel evolution of the small and large joint lesions and the late appearance of osteonecrotic changes in our patients suggest that avascular osteonecrosis is related to the osteoarticular progression of the longstanding SS.  相似文献   
6.
The pathogenesis of diffuse connective tissue diseases (DCTD) is still unknown and has been extensively studied regarding its autoimmunity aspects related to extracellular matrix (ECM) remodelling, with an emphasis on the collagens at the inflammatory site. The present paper describes the pulmonary architectural and repair/remodelling responses to injury after immunization of rabbits with human type V collagen. The animal model consisted of rabbits immunized with collagen mixed with Freund's adjuvant and sacrificed 7, 15, 30, 75, and 120 days after the first of four doses of antigen. Pulmonary architecture remodelling response was evaluated by histology, morphometry, and the immunofluorescence method, according to compartments of reference (parenchyma and interstitium) and injury: 1 inflammation (polymorphonuclear and mononuclear cells); 2-repair (fibrosis) and 3-ECM remodelling (collagen system). The results showed an intense inflammatory involvement of the pulmonary vascular and bronchiolar parenchyma, characterized by increased wall thickness in small arteries, infiltrations by pseudoeosinophils, and mononuclear cells. Progressive remodelling of the pulmonary ECM was characterized by collagen deposition in the septal and bronchovascular interstitium, especially in rabbits sacrifices at 75 and 120 days. The ECM remodelling process was not reproduced when rabbits were inoculated with collagen types I and III. We conclude that the model reproduces morphologic changes similar to those observed in many DCTD, encouraging realization of other experiments to gain a better understanding of the pathogenesis of these diseases.  相似文献   
7.
Our objectives were (1) to compare lymphocyte subpopulation apoptosis rates in SSc patients versus healthy controls and (2) to compare Bcl-2 and NF-kappa B expression in cultured CD8 lymphocytes of SSc patients versus controls. Peripheral blood samples were obtained from 27 SSc patients meeting the American College of Rheumatology criteria for SSc and 28 healthy individuals. Mononuclear cells were isolated by Ficoll-Hypaque density gradient separation and cultured for 48 hr. For determination of apoptosis within specific cell populations, samples were labeled with PE-conjugated monoclonal antibody to CD8, CD4, and a FITC-conjugated monoclonal antibody to Annexin V. Flow cytometry was carried out with a FACS operating with Cellquest software. CD8+ lymphocytes were positively selected with magnetic microbeads conjugated to antihuman CD8. CD8 T cells were separated, then incubated with activation for 48 hr, and NF-kappa B and Bcl-2 analysis was carried out using Western immunoblotting. The CD4:CD8 ratio was increased in SSc compared to controls (2.6 +/- 1.13 vs.1.87 +/- 0.76; P = 0.018). The spontaneous apoptosis rate of SSc CD8 lymphocytes was increased compared to that of controls of (21.9 +/- 13.7 vs. 13.3 +/- 9.9; P = 0.019). No difference was found in the rate of CD4 apoptosis of SSc patients versus controls (9.8 +/- 5.2 vs. 7.18 +/- 4.89%; P = ns). The expression of NF-kappa B in SSc CD8 lymphocytes was decreased compared with that of CD8 lymphocytes from healthy controls (144 +/- 13 vs. 188 +/- 11; P = 0.018). Whereas expression of Bcl-2 was similar in activated CD8+ T cells of SSc patients and healthy controls, CD8+ T cell apoptosis rate was found to be in reverse correlation with expression of NF-kappa B in these cells ( r = - 0.53, P = 0.029). The increased CD4:CD8 ratio in SSC may result from increased CD8+ T cell apoptosis. Increased SSc CD8 T cell apoptosis is associated with low levels of NF-kappa B.  相似文献   
8.
Summary The Toxic Syndrome (TS) caused by ingestion of adulterated rapeseed oil in Spain is a new disease of multisystemic character whose aetiology and pathogenesis remains unknown. The most prominent pathological feature is a peculiar non-necrotizing vasculitis, that affects mainly the intima and involves vessels of every type and size in practically every organ. The TS begins with an acute clinical picture with pleuropneumopathy, fever, headaches, exanthems and eosinophilia. In these early clinical phases the main pathological findings were observed in the lungs and consisted of intense pulmonary interstitial oedema with scanty inflammatory mononuclear infiltrates. Ultrastructural study revealed hydropic degeneration of pneumocytes types I and II with desquamation of type I. The patients in this phase died of respiratory failure, later deaths were due to thromboembolic complications. Later still the patients developped a neuromuscular syndrome, sclerodermiform skin lesions and severe weight loss and died predominantly of infectious complications and respiratory failure. The anatomopathological picture in the peripheral nerves was that of inflammatory neuropathy with a lymphocytic perineuritis that led to perineural fibrosis with secondary axonal degeneration. The muscle presented an interstitial inflammatory myopathy at first followed by a neurogenic muscular atrophy. The skin lesions in the late phases consisted in dermal or dermal and subdermal fibrosclerosis, with vasculitis of the small arteries in the lower dermis. The salivary glands and pancreas showed vasculitis and interstitial inflammation which progressed to interstitial fibrosis and parenchymal atrophy.  相似文献   
9.
蝮蛇抗栓酶治疗硬皮病的临床观察   总被引:4,自引:0,他引:4  
蝮蛇抗栓酶治疗硬皮病还未见报道,本文治疗10例,其中系统型7例、局限型3例,具有一定疗效  相似文献   
10.
Melorheostosis is characterised radiologically by hyperostotic linear densities in bone. These densities have a peculiarly segmental distribution which does not correspond with the anatomical course of blood vessels or mixed nerve roots of the limbs. So far this distribution has lacked any valid explanation, although it has been suggested to be a developmental error as a result of an embryonic metameric disturbance. Inman and Saunders in 1944 described a sensory nerve supply to skeletal structures with sclerotomes representing the zones of the skeleton supplied by individual spinal sensory nerves. Radiographs of 30 cases from the Radiological Museum of the Institute of Orthopaedics, London, have been reviewed and an attempt has been made to correlate the sclerosing lesions with the sclerotomes. The investigation was handicapped by paucity of films and clinical information, but in 19 cases the skeletal abnormalities were considered to correspond with a single sclerotome or part thereof. These studies were convincing when films of an affected hand or foot were available. In the remaining 11 cases multiple sclerotomes appeared to be involved and the clinical manifestations were correspondingly more severe. It is proposed that melorheostosis may be the late result of a segmental sensory nerve lesion, to account for its sclerodermal distribution. The association with linear scleroderma is discussed, since it has been suggested that these cutaneous lesions are related to the same nerve segment. Eight cases showed para-articular ossification of soft tissues which may be related to involvement of a corresponding myotome.  相似文献   
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