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81.
Rehab M. Samaka Moshira M. Abd El‐Wahed Hayam A. Aiad Mona A. Kandil Dalia R. Al‐Sharaky 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(4):316-328
John Cunningham virus (JCV) encodes an oncogenic T‐antigen, which is capable of interacting with key growth regulatory pathways. JCV definite role as causal agent of human cancer, still awaits final confirmation. The present study was conducted to assess the possible role of JCV in Egyptian colorectal carcinoma (CRC) and correlate the expression with the clinicopathological features and survival. JCV in situ hybridization (ISH) signals and large T antigen immunoreactivity were examined in 87 colonic specimens. Positive glandular JCV ISH signals were detected in 20%, 25% and 40% of normal, adenoma and CRC cases respectively. Stromal JCV ISH signals were identified in 26% of CRC cases and 5% of adenoma however, normal mucosa did not show stromal positivity with significant difference (p = 0.03). Glandular JCV expression was significantly associated with high grade (p = 0.03), high mitotic index (p=0.02) and low apoptotic index (p = 0.00). Positive stromal signals were significantly associated with low apoptosis (p = 0.00). No positive nuclear immunostaining of JCV large T antigen was detected in all specimens. JCV stromal expression was the 2nd most powerful indicator of short survival and bad prognosis (p = 0.03) in CRC patients. JCV might play an etiological role in CRC tumorogenesis and short survival in Egyptian CRC patients. 相似文献
82.
Bin Luo Yong-yao Gu Xiao-dong Wang Gang Chen Zhi-gang Peng 《Pathology, research and practice》2018,214(11):1854-1867
Diffuse large B-cell lymphoma (DLBCL) is the most main subtype in non-Hodgkin lymphoma. After chemotherapy, about 30% of patients with DLBCL develop resistance and relapse. This study was to identify potential therapeutic drugs for DLBCL using the bioinformatics method. The differentially expressed genes (DEGs) between DLBCL and non-cancer samples were downloaded from the Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEGs were analyzed using the Database for Annotation, Visualization, and Integrated Discovery. The R software package (SubpathwayMiner) was used to perform pathway analysis on DEGs affected by drugs found in the Connectivity Map (CMap) database. Protein–protein interaction (PPI) networks of DEGs were constructed using the Search Tool for the Retrieval of Interacting Genes online database and Cytoscape software. In order to identify potential novel drugs for DLBCL, the DLBCL-related pathways and drug-affected pathways were integrated. The results showed that 1927 DEGs were identified from TCGA and GEO. We found 54 significant pathways of DLBCL using KEGG pathway analysis. By integrating pathways, we identified five overlapping pathways and 47 drugs that affected these pathways. The PPI network analysis results showed that the CDK2 is closely associated with three overlapping pathways (cell cycle, p53 signaling pathway, and small cell lung cancer). The further literature verification results showed that etoposide, rinotecan, methotrexate, resveratrol, and irinotecan have been used as classic clinical drugs for DLBCL. Anisomycin, naproxen, gossypol, vorinostat, emetine, mycophenolic acid and daunorubicin also act on DLBCL. It was found through bioinformatics analysis that paclitaxel in the drug-pathway network can be used as a potential novel drug for DLBCL. 相似文献
83.
Xingchen Wu Seyoum Nerisho Prasun Dastidar Pertti Ryymin Ritva Järvenpää Hannu Pertovaara Hannu Eskola Pirkko‐Liisa Kellokumpu‐Lehtinen 《NMR in biomedicine》2013,26(9):1186-1194
To compare different MRI sequences for the detection of lesions and the evaluation of response to chemotherapy in patients with diffuse large B‐cell lymphoma (DLBCL), 18 patients with histology‐confirmed DLBCL underwent 3‐T MRI scanning prior to and 1 week after chemotherapy. The MRI sequences included T1‐weighted pre‐ and post‐contrast, T2‐weighted with and without fat suppression, and a single‐shot echo‐planar diffusion‐weighted imaging (DWI) with two b values (0 and 800 s/mm2). Conventional MRI sequence comparisons were performed using the contrast ratio between tumor and normal vertebral body instead of signal intensity. The apparent diffusion coefficient (ADC) of the tumor was measured directly on the parametric ADC map. The tumor volume was used as a reference for the evaluation of chemotherapy response. The mean tumor volume was 374 mL at baseline, and decreased by 65% 1 week after chemotherapy (p < 0.01). The T2‐weighted image with fat suppression showed a significantly higher contrast ratio compared with images from all other conventional MRI sequences, both before and after treatment (p < 0.01, respectively). The contrast ratio of the T2‐weighted image with fat suppression decreased significantly (p < 0.01), and that of the T1‐weighted pre‐contrast image increased significantly (p < 0.01), after treatment. However, there was no correlation between the change in contrast ratio and tumor volume. The mean ADC value was 0.68 × 10–3 mm2/s at baseline; it increased by 89% after chemotherapy (p < 0.001), and the change in ADC value correlated with the change in tumor volume (r = 0.66, p < 0.01). The baseline ADC value also correlated inversely with the percentage change in ADC after treatment (r = ?0.62, p < 0.01). In conclusion, this study indicates that T2‐weighted imaging with fat suppression is the best conventional sequence for the detection of lesions and evaluation of the efficacy of chemotherapy in DLBCL. DWI with ADC mapping is an imaging modality with both diagnostic and prognostic value that could complement conventional MRI. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
84.
Sukhdeep Bains N. Vidhya Usha Kim R. Shanti J. Devanand 《Orbit (Amsterdam, Netherlands)》2015,34(6):338-339
Secondary cutaneous dissemination from an orbital diffuse large B cell lymphoma has not been described before. The authors report an unusual case of anaplastic variant of diffuse large B cell lymphoma which primarily presented in the orbit and during the course of disease had subcutaneous dissemination. 相似文献
85.
Eva V George John Pharm Courtney Houston Semar Al-Quran Grey Brian Huijia Dong Wang Hai Westley Reeves Li-Jun Yang 《International journal of clinical and experimental pathology》2013,6(8):1631-1642
Breast implant associated anaplastic large cell lymphoma (BIA-ALCL) is a recently recognized clinical entity, with only 39 well-documented cases reported worldwide, including 3 fatalities. Because of its rarity, the clinical and pathologic features of this malignancy have yet to be fully defined. Moreover, the pathogenesis of ALCL in association with textured silicone gel breast implants is poorly understood. Here we report a case of BIA-ALCL arising in a 67-year-old woman with a mastectomy due to breast cancer followed by implantation of textured silicone gel breast prosthesis. The patient presented with breast enlargement and tenderness 8 years following reconstructive surgery. MRI revealed a fluid collection surrounding the affected breast implant. Pathologic examination confirmed the presence of malignant ALCL T cells that were CD30+, CD8+, CD15+, HLA-DR+, CD25+ ALK- and p53. A diagnosis of indolent BIA-ALCL was made since tumor cells were not found outside of the capsule. Interestingly, an extensive mixed lymphocytic infiltrate and ectopic lymphoid tissue (lymphoid neogenesis) adjacent to the fibrous implant capsule were present. The patient was treated with capsulectomy and implantation of new breast prostheses. Six months later, the patient was found to have BIA-ALCL involvement of an axillary lymph node with cytogenetic evolutionof the tumor. To our knowledge, this is the sixth reported case of aggressive BIA-ALCL. Unique features of this case include the association with lymphoid neogenesis and the in vivo cytogenetic progression of the tumor. This case provides insight into the potential role of chronic inflammation and genetic instability in the pathogenesis of BIA-ALCL. 相似文献
86.
Clinicopathological analysis of programmed cell death 1 and programmed cell death ligand 1 expression in the tumour microenvironments of diffuse large B cell lymphomas 下载免费PDF全文
87.
Pallavi Khattar Puneet Bedi Marion Gonzalez Minghao Zhong Changhong Yin Weihua Huang Humayun K. Islam John T. Fallon 《Pathology, research and practice》2018,214(4):593-598
Primary (localized) non-Hodgkin lymphoma (NHL) of the ovary is extremely rare; only a few cases have been reported in the literature. We report two cases of primary ovarian lymphoma (POL), one involving bilateral ovaries in a 15-year-old girl and other involving one ovary in a 5-year-old girl. This report describes detailed clinical, histopathological, and imaging findings, along with the review of literature of primary diffuse large B-cell lymphoma (DLBCL) arising from an ovary. In addition, we describe findings of targeted capture panel sequencing on both tumors and identify the major genetic mutations that are recurrently mutated in pan-cancers. Compared to the genomic mutation features of major subtypes of DLBCL, we distinguish that each POL belongs to distinctive subtypes, GCB (germinal center B-cell subtype) DLBCL and ABC (activated B-cell subtype) DLBCL, respectively. The findings from the genomic analysis may help to understand the pathogenesis of POL and to guide potential targeted therapy in the future. 相似文献
88.
89.
90.
LTC Edwin S. Beatrice MC Georg D. Frisch MBA 《Archives of environmental & occupational health》2013,68(5):322-326
The eyes of rhesus monkeys were exposed to argon (514.5 nm) and ruby (694.3 nm) laser irradiation using various retinal image diameters which were estimated by microphotometric techniques. The experimental design for both wavelengths produced image diameters of 40μ to 50μ for the “minimal” case and approximately 500μ to 1,000μ for the larger irradiance series employed. Extramacular retinal exposure sites were examined by ophthalmoscopic and histopathological techniques. Flat preparations of the pigmented epithelium and sensory layers of the retina were utilized in the confirmation of damage at low power levels. All data were statistically analyzed to establish trends, and results were compared for the wavelengths employed. Results indicate that retinal damage is primarily dependent on energy distribution as a function of image diameter and exposure duration. 相似文献