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131.

Background:

Histopathological prognostication relies on morphological pattern recognition, but as numbers of biomarkers increase, human prognostic pattern-recognition ability decreases. Follicular lymphoma (FL) has a variable outcome, partly determined by FOXP3 Tregs. We have developed an automated method, hypothesised interaction distribution (HID) analysis, to analyse spatial patterns of multiple biomarkers which we have applied to tumour-infiltrating lymphocytes in FL.

Methods:

A tissue microarray of 40 patient samples was used in triplex immunohistochemistry for FOXP3, CD3 and CD69, and multispectral imaging used to determine the numbers and locations of CD3+, FOXP3/CD3+ and CD69/CD3+ T cells. HID analysis was used to identify associations between cellular pattern and outcome.

Results:

Higher numbers of CD3+ (P=0.0001), FOXP3/CD3+ (P=0.0031) and CD69/CD3+ (P=0.0006) cells were favourable. Cross-validated HID analysis of cell pattern identified patient subgroups with statistically significantly different survival (35.5 vs 142 months, P=0.00255), a more diffuse pattern associated with favourable outcome and an aggregated pattern with unfavourable outcome.

Conclusions:

A diffuse pattern of FOXP3 and CD69 positivity was favourable, demonstrating ability of HID analysis to automatically identify prognostic cellular patterns. It is applicable to large numbers of biomarkers, representing an unsupervised, automated method for identification of undiscovered prognostic cellular patterns in cancer tissue samples.  相似文献   
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Background: Historically, patients with thick (4 mm) primary melanoma have not been considered candidates for elective lymph node dissection, because their risk for occult distant disease is significant. Sentinel lymph node (SLN) biopsy offers an alternative approach to assess disease in the regional nodal basin, but no studies have specifically addressed the role for this technique in patients with thick melanoma. Although adjuvant therapy benefits patients who develop nodal metastases, data that supports its routine use in all patients with thick melanoma is both limited and controversial. This study was performed to determine whether pathological status of the SLN is an important risk factor in this heterogeneous group and, thus, provides a rationale for SLN biopsy.Methods: The records of 131 patients with primary cutaneous melanoma whose primary tumors were at least 4 mm thick and who underwent lymphatic mapping and SLN biopsy were reviewed. Several known prognostic factors, i.e., tumor thickness, ulceration, Clark level, location, sex, as well as SLN pathological status were analyzed with respect to disease-free and overall survival.Results: Lymphatic mapping and SLN biopsy was successful in 126 (96%) of 131 patients who underwent the procedure. In 49 patients (39%), the SLN biopsy was positive by conventional histology, although it was negative in 77 patients (61%). The median follow-up was 3 years. Although presence of ulceration and SLN status were independent prognostic factors with respect to disease-free and overall survival, SLN status was the most powerful predictor of overall survival by univariate and multivariate analyses.Conclusions: Lymphatic mapping and SLN biopsy is a highly accurate method of staging lymph node basins at risk for regional metastases in patients with thick melanoma and identifies those patients who may benefit from earlier lymphadenectomy as well as patients with a more favorable prognosis. Pathological status of the SLN in these patients with clinically negative nodes is the most important prognostic factor for survival and is essential to establish stratification criteria for future adjuvant trials in this high-risk group.Presented at the 52nd Annual Meeting of the Society of Surgical Oncology, Orlando, Florida, March 4–7, 1999.  相似文献   
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Objective: To examine among people attending outpatient clinics aged 50–74 at average risk of colorectal cancer (CRC): 1) The proportion who report: a) faecal occult blood test (FOBT) within the past two years; and b) colonoscopy within the past five years, including the reasons for undergoing colonoscopy; 2) characteristics associated with under‐screening; 3) For those who are under‐screened, the proportion who are: a) willing to receive help and the acceptability of different methods of receiving help, and; b) unwilling to receive help and reasons for this. Methods: Cross‐sectional survey of 197 participants attending a major regional hospital in New South Wales, Australia. Multivariable logistic regression was used to determine correlates of under‐screening. Results: A total of 59% reported either FOBT in the past two years or colonoscopy in the past five years. Of those reporting colonoscopy in the past five years, 21% were potentially over‐screened. Males were more likely than females to be under‐screened. Of those under‐screened (41%), fewer than half were willing to receive screening advice. Conclusions and implications for public health: A significant proportion of people attending outpatient clinics are under‐screened for CRC, with some people also over‐screened. There is a need to explore strategies to overcome both under‐ and over‐screening.  相似文献   
137.
Background and aims Mutations in the DLG5 gene are associated with an increased risk of inflammatory bowel disease (IBD) in some European populations. Initial investigation of a British IBD population showed evidence of association of one of three DLG5 variants, R30Q, in a family-based collection but not in a case-control cohort. We have now examined the association of the R30Q polymorphism in a large cohort of British IBD cases, tested for interaction between the DLG5 and CARD15 genes and assessed possible association of DLG5 with clinical features of Crohn’s disease (CD) and ulcerative colitis (UC). Materials and methods DLG5 R30Q and the CARD15 polymorphisms, Arg702Trp, Gly908Arg and Leu1007fs were genotyped in 1,148 IBD cases and 749 controls. DLG5 R30Q was also analysed in cases stratified by CARD15 genotype, disease subtype and smoking history. Results/findings No significant difference in frequencies of the R30Q variant was observed between IBD cases (9.9%) and controls (10.1%) or in cases analysed separately as CD and UC. There was also no significant difference in the frequency of R30Q between CD cases carrying risk-associated CARD15 alleles and those that did not. The frequency of R30Q was higher in CD cases with ileal disease than cases without (p=0.042) and higher in CD cases who had smoked than in nonsmokers (p=0.009). Interpretation/conclusion The R30Q variant in the DLG5 gene does not appear to be associated with an overall increase in the risk of disease in a British IBD cohort, but differences in its frequency in subgroups of CD patients warrant further investigation.  相似文献   
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BACKGROUND: Body-composition changes are common in individuals infected with human immunodeficiency virus. The purpose of the present study was to measure, as a model of wasting in acquired immunodeficiency syndrome (AIDS), longitudinal body-composition changes in macaques infected with simian immunodeficiency virus (SIV). METHODS: Twelve juvenile macaques were inoculated with SIVmac239. Immunologic, virologic, somatometric, and dual-energy x-ray-absorptiometry measurements were performed prospectively every 4 weeks for 72 weeks and were compared to measurements taken from 8 uninfected control macaques. RESULTS: During the first 4 weeks, body-fat percentage decreased in the SIV-infected macaques while lean-tissue percentage increased; during weeks 4-72, these macaques lost a greater percentage of total fat tissue but had more subcutaneous-fat deposition than did the uninfected control macaques. Just prior to death, the SIV-infected macaques that died (n=7) had a greater loss in body-mass index, abdominal fat, fat tissue, and lean tissue, compared with that in SIV-infected macaques that survived (n=5). CONCLUSIONS: Body-composition changes in SIV-infected juvenile macaques exhibit 3 phases: during acute infection, loss of body weight from fat tissue; a compensation period during which macaques grow, but at a reduced rate; and a terminal phase, during which tissue is lost from all body compartments. The SIV-infected juvenile macaque provides a useful model for the investigation of wasting in AIDS, particularly for pediatric AIDS wasting.  相似文献   
140.
Peroxisome proliferator-activated receptor gamma (PPAR gamma) agonists, including the glitazone class of drugs, are insulin sensitizers that reduce glucose and lipid levels in patients with type 2 diabetes mellitus. To more fully understand the molecular mechanisms underlying their therapeutic actions, we have characterized the effects of the potent, tyrosine-based PPAR gamma ligand GW1929 on serum glucose and lipid parameters and gene expression in Zucker diabetic fatty rats. In time-course studies, GW1929 treatment decreased circulating FFA levels before reducing glucose and triglyceride levels. We used a comprehensive and unbiased messenger RNA profiling technique to identify genes regulated either directly or indirectly by PPAR gamma in epididymal white adipose tissue, interscapular brown adipose tissue, liver, and soleus skeletal muscle. PPAR gamma activation stimulated the expression of a large number of genes involved in lipogenesis and fatty acid metabolism in both white adipose tissue and brown adipose tissue. In muscle, PPAR gamma agonist treatment decreased the expression of pyruvate dehydrogenase kinase 4, which represses oxidative glucose metabolism, and also decreased the expression of genes involved in fatty acid transport and oxidation. These changes suggest a molecular basis for PPAR gamma-mediated increases in glucose utilization in muscle. In liver, PPAR gamma activation coordinately decreased the expression of genes involved in gluconeogenesis. We conclude from these studies that the antidiabetic actions of PPAR gamma agonists are probably the consequence of 1) their effects on FFA levels, and 2), their coordinate effects on gene expression in multiple insulin-sensitive tissues.  相似文献   
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