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41.
42.
Germline mutations of the CHEK2 gene have been reported in some myeloid and lymphoid malignancies, but their impact on development of essential thrombocythemia has not been studied. In 16 out of 106 (15.1%) consecutive patients, newly diagnosed with essential thrombocythemia, we found one of four analyzed CHEK2 mutations: I157T, 1100delC, IVS2+1G>A or del5395. They were associated with the increased risk of disease (OR=3.8; P=0.002). The median age at ET diagnosis among CHEK2+/JAK2V617F+ patients was seven years lower than that among CHEK2-/JAK2V617F+ (52 vs. 59 years; P=0.04), whereas there was no difference in the medians of hematologic parameters between these groups. The results obtained suggest that CHEK2 mutations could potentially contribute to the susceptibility to essential thrombocythemia. The germline inactivation of CHEK2, as it seems, has no direct impact on the development of disease, but it could cause disruption of cell cycle checkpoints and initiate or support the cancerogenic process of essential thrombocythemia at a younger age.  相似文献   
43.

Introduction

Formation of adhesions after laparoscopic hernia repair using the intra-peritoneal onlay mesh (IPOM) procedure can lead to intestinal obstruction or mesh erosion into intestinal lumen. The aims of this study included: measurement of adhesion formation with Dynamesh IPOM after laparoscopic intraperitoneal implantation, and assessment of the occurrence of isolated adhesions at the fastening sites of slowly absorbable sutures.

Material and methods

Twelve healthy pigs underwent laparoscopic implantation of 2 Dynamesh IPOM mesh fragments each, one was fastened with PDSII, and the other with Maxon sutures. An assessment of adhesion formation was carried out after 6 weeks and included an evaluation of surface area, hardness according to the Zhulke scale, and index values. The occurrence of isolated adhesions at slowly absorbable suture fixation points was also analyzed.

Results

Adhesions were noted in 83.3% of Dynamesh IPOM meshes. Adhesions covered on average 37.7% of the mesh surface with mean hardness 1.46 and index value 78.8. In groups fixed with PDS in comparison to Maxon sutures adhesions covered mean 31.6% vs. 42.5% (p = 0.62) of the mesh surface, mean hardness was 1.67 vs.1.25 (p = 0.34) and index 85.42 vs. 72.02 (p = 0.95).

Conclusions

The Dynamesh IPOM mesh, in spite of its anti-adhesive layer of PVDF, does not prevent the formation of adhesions. Adhesion hardness, surface area, and index values of the Dynamesh IPOM mesh are close to the mean values of these parameters for other commercially available 2-layer meshes. Slowly absorbable sutures used for fastening did not increase the risk of adhesion formation.  相似文献   
44.
Phyllodes tumors (PTs) are classified as fibroepithelial tumors and their histologic grade is determined primarily by the features of the stromal component. In this study, we examined the expression profiles of autophagy-related proteins in the stromal component of PTs and analyzed their clinical implications. We selected 204 human PT samples which were excised and diagnosed at Severance Hospital from 2000 to 2008 and created tissue microarray (TMA) blocks. Immunohistochemical assays for autophagy-related proteins (beclin-1, LC3A, LC3B, and p62) were then performed on these samples. The surgical specimens from higher grade PTs less frequently displayed cytoplasmic expression of beclin-1, LC3A, LC3B, and p62 in the stromal component (p<0.001). In univariate analysis, the following profiles were associated with shorter disease-free survival and overall survival: nuclear beclin-1 positivity in the stromal component (p=0.013 and p=0.044, respectively), LC3A positivity in the stromal component (p<0.001 and p<0.001, respectively), and p62 positivity in the stromal component (p=0.012 and p=0.004, respectively). In conclusion, we determined that increased activity of autophagy-related proteins correlated with a higher histologic grade and poorer prognosis in PTs. These results lead us to conclude that the autophagy activity of the stromal cells plays a key role in the progression of PTs.  相似文献   
45.
Hepatoid adenocarcinoma (HAC) is a rare type of extrahepatic carcinoma whose morphology is similar to that of hepatocellular carcinoma (HCC). Metachronous HCC and HAC in the same patient is extremely rare. The case of a 68-year-old man with chronic hepatitis B infection who had both HCC and HAC of the stomach is reported herein. Nine years previously this patient had been diagnosed with HCC and received a right lobectomy. HCC that recurred at the caudate lobe at 6 months after the operation was successfully treated with transarterial chemoembolization. The patient was followed up regularly thereafter without evidence of tumor recurrence for 9 years. In July 2010 his serum alpha-fetoprotein (AFP) level elevated from 6.5 ng/mL to 625.4 ng/mL, and he developed a probable single metastatic lymph node around the hepatic artery without intrahepatic lesions. Subsequent evaluation with upper endoscopy revealed a 4-cm ulcerative lesion on the antrum of the stomach. Subtotal gastrectomy was performed with lymph-node dissection. Histologic examination revealed a special type of extrahepatic AFP-producing adenocarcinoma-HAC with lymph-node metastasis-which indicates that HAC can be a cause of elevated AFP even in patients with HCC. HAC should be considered if a patient with stable HCC exhibits unusual elevation of AFP.  相似文献   
46.
47.
The differential diagnosis in anogenital ulcer-adenopathy syndrome in men who have sex with men (MSM) is becoming more complex, particularly with lymphogranuloma venereum and syphilis re-establishing endemicity among MSM. Sexual contact has been shown to transmit methicillin-resistant Staphylococcus aureus (MRSA), probably through intimate skin-to-skin contact. We present a case of MRSA genital ulceration and local lymphadenopathy in a man whose sexual partners are men, reporting high-risk sexual behaviour, highlighting the importance of also considering MRSA infection in these cases, and the potential for spread of MRSA infection in the MSM community.  相似文献   
48.
Atrial fibrillation (AF) ablation has evolved to the treatment of choice for patients with drug-resistant and symptomatic AF. Pulmonary vein isolation at the ostial or antral level usually is sufficient for treatment of true paroxysmal AF. For persistent AF ablation, drivers and perpetuators outside of the pulmonary veins are responsible for AF maintenance and have to be targeted to achieve satisfying arrhythmia-free success rate. Both complex fractionated atrial electrogram (CFAE) ablation and linear ablation are added to pulmonary vein isolation for persistent AF ablation. Nevertheless, ablation failure and necessity of repeat ablations are still frequent, especially after persistent AF ablation. Pulmonary vein reconduction is the main reason for arrhythmia recurrence after paroxysmal and to a lesser extent after persistent AF ablation. Failure of persistent AF ablation mostly is a consequence of inadequate trigger ablation, substrate modification or incompletely ablated or reconducting linear lesions. In this review we will discuss these points responsible for AF recurrence after ablation and review current possibilities on how to overcome these limitations.  相似文献   
49.
50.
Disc degeneration and the subsequent herniation and/or rupture of the intervertebral disc (IVD) are due to a failure of the extracellular matrix of the annulus to contain the contents of the nucleus. This results from inadequate maintenance of the matrix components as well as the proteolytic activity of matrix metalloproteinases (MMPs) that degrade matrix molecules. Arresting progression of disc degeneration in the annulus holds greater clinical potential at this point than prevention of its onset in the nucleus. Therefore, in this study, we have therapeutic aims that would decrease levels of the cytokines and growth factors that indirectly lead to disc degeneration via stimulating MMP and increase levels of several beneficial growth factors, such as transforming growth factor‐β, with the addition of platelet‐rich plasma (PRP) that would stimulate cell growth and matrix synthesis. For this study, we attempted to address these imbalances of metabolism by using tumor necrosis factor‐α treated annulus fibrosus cells isolated from porcine IVD tissue and incubating the cells in a growth factor rich environment with PRP. These results indicate that the PRP in vitro increased the production of the major matrix components (type II collagen and aggrecan) and decreased the inhibitory collagenase MMP‐1. This application will address a therapeutic approach for intervening early in the degenerative process.  相似文献   
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