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991.
The aim of this prospective study was to compare the expression of the Notch receptor family with the biomarker for stimulation of satellite cells (SC), which are responsible for functional adaptation.Tissue samples from the masseter muscle were taken presurgically and 7 months later. Samples from controls came from the extraction of third molars. The expression of Notch 1 to 4 and the satellite cell markers CD34, Pax7, and MyoD1 were investigated. PCR was used for relative quantification of gene expression, which was calculated with the ΔΔCT method.The study involved 38 white patients — 10 prognathic, 18 retrognathic, and 10 orthognathic controls. The median value for Notch 1 was significantly reduced presurgically for prognathic (0.46, SD 0.45) and retrognathic (0.57, SD 0.35) patients compared with the controls. Postsurgically, Notch 2 was significantly upregulated in the prognathic group (0.55, SD 0.28/1.37, SD 0.85). Similarly, there was upregulation of Notch 3 in the prognathic group (0.33, SD 0.42/0.59, SD 1.37) and downregulation in retrognathic patients (0.59, SD 0.79/0.52, SD 0.97). Upregulations for the satellite cell markers CD34 and Pax7 were also found in prognathic patients.The significant upregulation of Notch 1–3 and CD34 in prognathics, but unchanged MyoD expression, signals high stimulation for SC and maintenance of the regeneration cell pool. A lower expression of Notch and SC in retrognathic patients could be responsible for weak functional adaptation.  相似文献   
992.
AIM: To evaluate the risk factors-other than nonsteroidal anti-inflammatory drugs-for colonic diverticular bleeding in a westernized population. METHODS: One hundred and forty patients, treated for symptomatic diverticular disease in a community based hospital, were included. Thirty (21%) had signs of diverticular bleeding. Age, gender, and the results of colonoscopy were collected and compared to a group of patients with nonbleeding symptomatic diverticulosis. Records were reviewed for comorbidities, such as obesity, alcohol consumption, smoking habits and metabolic diseases. Special emphasis was put on arterial hypertension, cardiovascular events, diabetes mellitus, hyperuricemia and hypercholesterinemia. RESULTS: There was no difference between patients with diverticular hemorrhage and those with nonbleeding symptomatic diverticulosis regarding gender ratio (male/female 9/21 vs 47/63) and diverticular Iocalisation. Bleeding patients differed in respect to age (73.4± 9.9 vs 67. 8± 13.0, P 〈 0.013). Significant differences were found between both groups regarding the presence of hyperuricemia and use of steroids and nonsteroidal anti-inflammatory drugs. Patients with three concomitant metabolic diseases were also identified as being at risk of bleeding. A forward stepwise logistic regression analysis revealed steroids, hyperuricemia and the use of calcium-channel blockers as independent risk factors of bleeding.CONCLUSION: Beside nonsteroidal anti-inflammatory steroid drug use, antihypertensive medication and concomitant arteriosclerotic diseases are risk factors for colonic diverticular hemorrhage. Our results support the hypothesis of an altered arteriosclerotic vessel as the source of bleeding.  相似文献   
993.
Purpura fulminans features the sudden onset of large rapidly‐spreading areas of hemorrhagic skin necrosis. This is followed by a disseminated intravascular coagulopathy with consecutive consumption of anticoagulant factors. Patients with severe disease in whom therapy is delayed often develop shock with a poor prognosis.The mortality rate is about 30–40%. An elderly women developed purpura fulminans after a respiratory infection. Prompt diagnosis before shock symptoms had started was instrumental in producing a favorable clinical course.  相似文献   
994.
Olfactory loss may be a first sign of idiopathic Parkinson's disease.   总被引:3,自引:0,他引:3  
Recent studies support the idea of olfactory dysfunction as a very early sign of idiopathic Parkinson's disease (IPD). Aim of the present study was to clinically follow-up patients with idiopathic hyposmia to find out the percentage of patients developing IPD after 4 years time. At baseline, olfactory tests had been combined with transcranial sonography of the substantia nigra and (123)I-FP-CIT SPECT imaging. At the present neurological examination, 7% of the individuals with idiopathic hyposmia had developed clinical IPD. Altogether, 13% presented with abnormalities of the motor system. Our data suggest that a combination of olfactory testing and other tests may constitute a screening tool for the risk to develop IPD.  相似文献   
995.
We present the case of a 65-year-old woman with a short-term history of cognitive decline and neuropsychiatric symptoms. Neuroradiological examinations revealed a large left temporo-occipital cystic and calcified tumor mass measuring 6 cm in diameter, which was suspicious for an oligodendroglioma or a choroid plexus carcinoma. Neuropathological investigations finally revealed a gliosarcoma with extensive mesenchymal differentiation. The tumor demonstrated a biphasic pattern consisting of focal anaplastic glial components with vascular proliferation and necrosis. Adjacent sarcomatous tissue displayed pleomorphic fibroblastic cells surrounding metaplastic cartilage and osseous formation. Accounting for only approximately 2% of glioblastomas, gliosarcomas represent a rare entity of intrinsic CNS neoplasms. Exceedingly rare, the mesenchymal part of the gliosarcoma undergoes metaplastic transformation. Interestingly, in our case, the tumor exhibited features of both cartilaginous and osseous differentiation and multifocally showed a sharp transformation zone between highly malignant gliosarcomatous tumor areas and well-differentiated non-proliferative metaplastic regions.  相似文献   
996.
To report our experience with 17 children who underwent a liver transplantation (LT) for acute liver failure (ALF). All LT procedures (deceased and living donor) were offered. Since 2003 Molecular Adsorbents Recycling System (MARS) was proposed as bridging procedure. We monitored the perioperative course and the short- and long-term outcomes. All children developed pretransplant hepatic encephalopathy (mostly grades II and III); six needed ventilator support and three haemodialysis. Median PELD/MELD score was 30. MARS was used in five children with poor pretransplant prognostic factors: all five survived the LT without sequelae. We performed 13 deceased donor LT (seven whole, five split and onr reduced) and four left lateral LDLT. Postoperative complications were observed in 10 children, requiring re-operation in seven. Two children developed irreversible neurological disorders. After a median follow up of 45 months, 16 children are still alive. About 1- and 5-year cumulative patient survival rates are 94% with a corresponding graft survival of 88% and 81%, respectively. The combination of experienced paediatric ICU management, the application of new liver support devices, and the capacity to offer both living and deceased donor transplant alternatives in a timely fashion represent the best formula to achieve optimal results in children with ALF.  相似文献   
997.
998.
999.
The addition of chondroitin sulphate (CS) to bone cements with calcium phosphate has lead to an enhancement of bone remodeling and an increase in new bone formation in small animals. The goal of this study was to verify the effect of CS in bone cements in a large animal model simulating a clinically relevant situation of a segmental cortical defect of a critical size on bone–implant interaction and bone remodeling. The influence of adding CS to hydroxyapatite/collagen (HA/Col) composites on host response was assessed in a standard sheep tibia model. A midshaft defect of 3 cm was created in the tibiae of 14 adult female sheep. The defect was filled with a HA/Col cement cylinder in seven animals and with a CS‐modified hydroxyapatite/collagen (HA/Col/CS) cement cylinder in seven animals. In all cases the tibia was stabilized with an interlocked universal tibial nail. The animals in each group were analyzed with X‐rays, CT scans, histology, immunohistochemistry, and enzymehistochemistry, as well as histomorphometric measurements. The X‐ray investigation showed a significantly earlier callus reaction around the HA/Col/CS implants compared to HA/Col alone. The amount of newly formed bone at the end point of the experiment was significantly larger around HA/Col/CS cylinders both in the CT scan and in the histomorphometric analysis. There were still TRAP‐positive osteoclasts around the HA/Col implants after 3 months. The number of osteopontin‐positive osteoblasts and the direct bone contact were significantly higher around HA/Col/CS implants. We conclude that addition of CS enhances bone remodeling and new bone formation around HA/Col composites. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:15–21, 2009  相似文献   
1000.
Novel vaccination strategies against Mycobacterium tuberculosis (MTB) are urgently needed. The use of recombinant MTB antigens as subunit vaccines is a promising approach, but requires adjuvants that activate antigen-presenting cells (APCs) for elicitation of protective immunity. The mycobacterial cord factor Trehalose-6,6-dimycolate (TDM) and its synthetic analogue Trehalose-6,6-dibehenate (TDB) are effective adjuvants in combination with MTB subunit vaccine candidates in mice. However, it is unknown which signaling pathways they engage in APCs and how these pathways are coupled to the adaptive immune response. Here, we demonstrate that these glycolipids activate macrophages and dendritic cells (DCs) via Syk–Card9–Bcl10–Malt1 signaling to induce a specific innate activation program distinct from the response to Toll-like receptor (TLR) ligands. APC activation by TDB and TDM was independent of the C-type lectin receptor Dectin-1, but required the immunoreceptor tyrosine-based activation motif–bearing adaptor protein Fc receptor γ chain (FcRγ). In vivo, TDB and TDM adjuvant activity induced robust combined T helper (Th)-1 and Th-17 T cell responses to a MTB subunit vaccine and partial protection against MTB challenge in a Card9-dependent manner. These data provide a molecular basis for the immunostimulatory activity of TDB and TDM and identify the Syk–Card9 pathway as a rational target for vaccine development against tuberculosis.  相似文献   
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