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131.
PURPOSE: To test the hypothesis that chronic subdural hematoma (CSDH) enlarges by the causative factors, this study has performed. MATERIALS AND METHODS: In 10 patients with CSDH, coagulation factors in venous blood taken at the time of surgery and hematomic contents aspirated from the CSDH were studied, using both laboratory assays and microscopy. RESULTS: When compared to the range of normal plasma, the hematoma fluids demonstrated a marked reduction in factor II, V, VII, VIII, and X, moderate reduction of factors IX and XI, and slight reduction of factor XII. Activated protein C and antithrombin III levels were decreased. The FDP (Fibrinogen Degradation Product) levels in chronic subdural hematoma were extremely high. The endothelial cells of the macrocapillaries (also called 'sinusoid') showed numerous gap junctions between adjacent endothelial cells and a thinness or absence of the basement membrane, suggesting that the macrocapillaries are very fragile and susceptible to bleeding. CONCLUSION: Excessive coagulation in the hematoma, predominantly via the extrinsic clotting pathway, local hyperfibrinolysis, transmitted pulsations, and characteristics of the macrocapillaries play an important role in the leakage of blood and the enlargement of CSDH.  相似文献   
132.
Human linkage studies suggest that craniofacial deformities result from either genetic mutations related to cholesterol metabolism or high-cholesterol maternal diets. However, little is known about the precise roles of intracellular cholesterol metabolism in the development of craniofacial bones, the majority of which are formed through intramembranous ossification. Here, we show that an altered cholesterol metabolic status results in abnormal osteogenesis through dysregulation of primary cilium formation during bone formation. We found that cholesterol metabolic aberrations, induced through disruption of either Dhcr7(which encodes an enzyme involved in cholesterol synthesis) or Insig1 and Insig2(which provide a negative feedback mechanism for cholesterol biosynthesis), result in osteoblast differentiation abnormalities. Notably, the primary cilia responsible for sensing extracellular cues were altered in number and length through dysregulated ciliary vesicle fusion in Dhcr7 and Insig1/2 mutant osteoblasts. As a consequence, WNT/β-catenin and hedgehog signaling activities were altered through dysregulated primary cilium formation.Strikingly, the normalization of defective cholesterol metabolism by simvastatin, a drug used in the treatment of cholesterol metabolic aberrations, rescued the abnormalities in both ciliogenesis and osteogenesis in vitro and in vivo. Thus, our results indicate that proper intracellular cholesterol status is crucial for primary cilium formation during skull formation and homeostasis.  相似文献   
133.
134.

Study design

We document a spinal extradual arachnoid cyst treated by twist technique. The cyst is tightly adherent to the neural tissue or the dura, and the communication stalk is little or short.

Objective

To demonstrate the effectiveness of twist technique of closure of the communication stalk for the removal of spinal extradural arachnoid cyst.

Summary of background data

The standard treatment for a spinal extradural arachnoid cyst is complete excision of the cyst, followed by obliteration of the communication stalk and repair of the dural defect. To our knowledge, twist technique of the communication stalk for removal of spinal extradural arachnoid cyst has not been reported.

Methods

A 44-year-old woman presented with a 10-year history of pain and dysesthesia, initially in the posterior neck region and extending gradually to the distal portion of the right upper extremity. Pain and dysesthesia were exaggerated when she was lying down and relieved when standing or walking. She was diagnosed with an extradural arachnid cyst ranging from spinal regions T1 to T3 using MRI. Computerized tomography myelography revealed a mass located posterior to the spinal cord. Pooling of contrast medium was observed in the lesion indicating communication with the subarachnoid space. Laminectomy of the T1–T3 region was performed, preserving the spinous processes and the facet joints. A short communication stalk was found at the proximal root sleeve of right T3. This stalk was closed using twist technique.

Results

The patient experienced marked reduction of pain and dysesthesia after surgery, and the headache and blurred vision completely disappeared. Five days after the operation, she was discharged home in good condition. Postoperative 1 year later, the patient had completely recovered and resumed her normal life.

Conclusions

Twist technique can be seen safe and effective as another surgical option for spinal extradural arachnoid cysts containing a short stalk and dense fibrous adhesion with the dura mater.  相似文献   
135.

Background

Treatment for patients with N2-positive stage IIIA non-small cell lung cancer has been a controversial issue. The current study evaluated the outcomes in patients treated with trimodality therapy, which consisted of neoadjuvant radiation therapy concurrent with chemotherapy followed by surgical resection, with emphasis on clinical and pathologic nodal status.

Methods

We reviewed the records of 355 patients who were treated with trimodality therapy between 1997 and 2011.

Results

After completion of neoadjuvant chemoradiation, overall down-staging and complete response rates were 50.4 % (179 patients), and 13.2 % (47 patients), respectively. With median follow-up of 35.3 months, median times of progression-free survival (PFS) and overall survival (OS) were 16.3 months and 45.5 months, respectively. Seventeen patients (4.8 %) died of postoperative complications, and the remaining 338 patients were analyzed on prognostic factors. Old age (p = 0.032), pneumonectomy (p < 0.001), and ypN+ (p < 0.001) were found to be the significant prognosticators for worse PFS, and old age (p = 0.013), pneumonectomy (p < 0.001), and ypN+ (p < 0.001) were related to worse OS. Clinical N2 status did not influence either OS or PFS: the number of involved stations (single station vs. multi-station; p = 0.187 for PFS; p = 0.492 for OS), and bulk (clinically evident vs. microscopic; p = 0.902 for PFS; p = 0.915 for OS).

Conclusion

ypN stage was the most important prognosticator for both PFS and OS; however, neither initial bulk nor extent of cN2 disease influenced prognosis. Surgery following neoadjuvant chemoradiation should have contributed to improved clinical outcomes regardless of clinical nodal bulk and extent.  相似文献   
136.
137.

Background and Purpose

Products of Maillard reactions between aminoacids and reducing sugars are known to have anti-inflammatory properties. Here we have assessed the anti-arthritis effects of (E)-2,4-bis(p-hydroxyphenyl)-2-butenal and its possible mechanisms of action.

Experimental Approach

We used cultures of LPS-activated macrophages (RAW264.7 cells) and human synoviocytes from patients with rheumatoid arthritis for in vitro assays and the collagen-induced arthritis model in mice. NO generation, iNOS and COX2 expression, and NF-κB/IKK and STAT3 activities were measured in vitro and in joint tissues of arthritic mice, along with clinical scores and histopathological assessments. Binding of (E)-2,4-bis(p-hydroxyphenyl)-2-butenal to STAT3 was evaluated by a pull-down assay and its binding site was predicted using molecular docking studies with Autodock VINA.

Key Results

(E)-2,4-bis(p-hydroxyphenyl)-2-butenal (2.5–10 μg·mL−1) inhibited LPS-inducedNO generation, iNOS and COX2 expression, and NF-κB/IKK and STAT3 activities in macrophage and human synoviocytes. This compound also suppressedcollagen-induced arthritic responses in mice by inhibiting expression of iNOS and COX2, and NF-κB/IKK and STAT3 activities; it also reduced bone destruction and fibrosis in joint tissues. A pull-down assay showed that (E)-2,4-bis(p-hydroxyphenyl)-2-butenal interfered with binding of ATP to STAT3. Docking studies suggested that (E)-2,4-bis(p-hydroxyphenyl)-2-butenal bound to the DNA-binding interface of STAT3 possibly inhibiting ATP binding to STAT3 in an allosteric manner.

Conclusions and Implications

(E)-2,4-bis(p-hydroxyphenyl)-2-butenal exerted anti-inflammatory and anti-arthritic effects through inhibition of the NF-κB/STAT3 pathway by direct binding to STAT3. This compound could be a useful agent for the treatment of arthritic disease.  相似文献   
138.
It is predicted that the toxicity of nanoparticles may be different depending on the properties of the nanoparticles and biological system being tested. However, the factors that influence the toxicity of nanoparticles have not been adequately investigated. In this study, we characterized two types of TiO2 nanorods, anatase (ATO) and brookite (BTO), and compared their toxicity in vivo and in vitro. ATO and BTO differed from each other most notably in their surface areas. Treatment with the two TiO2 nanorods (10 µg ml–1) produced similar effects on the cell cycle in eight cell lines which are derived from potential target organs of nanoparticles, with the BTO eliciting stronger responses than ATO in all cell lines, among the cell lines, H9C2 showed the maximal change. Similarly, when mice were exposed to two TiO2 nanorods (1 mg kg–1), BTO induced clearer histopathological lesions and triggered a more robust secretion of inflammatory cytokines than ATO. Furthermore, we compared the cellular response of both TiO2 nanorods using BEAS‐2B cells, the human bronchial epithelial cell line. Both nanorods induced cell death by increasing the formation of autophagosome‐like vacuoles. The mitochondrial calcium concentration decreased by exposure of both types, but the distribution of lysosome and endoplasmic reticulum (ER) showed a clear difference between the two nanorods. Thus, we conclude that the surface area acts as an important factor which depends on toxicity of nanorod type‐TiO2 nanoparticles. Furthermore, the toxicity of nanoparticles varies according to the type of cells tested, and that the assembly of autophagosome‐like vacuoles is a critical part of the cellular response to nanoparticle exposure. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
139.
BackgroundThere has been renewed interest in HBV-associated ICC, because it could share a common carcinogenesis disease process with HCC. We investigated whether there is a difference in clinical outcome between ICC patients with HBV infection and those without any major risk factors for HCC.MethodsA total of 253 curatively resected, surgically diagnosed ICC patients were analyzed and divided into two groups according to the presence or absence of major risk factors for HCC: an HBV group (n = 45) and a non–HCC–risk (NHR) group (n = 208).ResultsLymph node metastasis was more frequently observed in the NHR group (HBV vs. NHR: 8.89% vs. 24.52%, P = 0.027). Patients in the HBV group demonstrated more favorable survival than those in the NHR group. However, this difference was not statistically significant (5-year survival rate, 54.7% vs. 42.3%, P = 0.128). Cumulative recurrence rate in the HBV group was 62.2%, which was not significantly different from 63.0% in the NHR group (P = 1.000).ConclusionThis study found that while ICC patients with HBV infection showed some favorable tumor characteristics, patients' stage-specific survival and recurrence rates were not significantly different compared to those without any major risk factors for HCC.  相似文献   
140.
Kim WU  Lee SH  Shim BY  Min JK  Hong YS  Park SH  Cho CS  Park CK  Kim HY 《Lupus》2000,9(2):147-150
A 25-year-old girl presented with progressive deterioration of right side weakness with decreased sensation on the left trunk. She had been treated with high dose steroid due to autoimmune thrombocytopenia for 2 months. Clinical, laboratory and immunologic studies revealed that she had systemic lupus erythematosus (SLE), MRI of spinal cord showed marginal contrast enhancing and fluid containing mass in the cord of the C5-6 level, suggesting intramedullary abscess. She underwent surgery of mass removal with biopsy. The pathologic findings from cord tissues revealed numerous acid fast bacilli (AFB) in necrotic tissues. After surgery and anti-tuberculous treatment, her neurologic symptoms were markedly improved with restoration of right side motor weakness. To our knowledge, this is the first case report of intramedullary tuberculosis in a patient with SLE. Since intramedullary tuberculosis may sometimes mimic neurologic complication of SLE itself, it may pose diagnostic and therapeutic confusion for clinicians. We report a case of spinal cord tuberculosis affecting C5, 6 level which was manifested as Brown-Sequard syndrome in a patient with SLE.  相似文献   
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