instruction:
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
question:
Context: Human breast tumors are heterogeneous and consist of phenotypically diverse cells. Breast cancer cells with a CD44+/CD24- phenotype have been suggested to have tumor-initiating properties with stem cell-like and invasive features, although it is unclear whether their presence within a tumor has clinical implications. There is also a large heterogeneity between tumors, illustrated by reproducible stratification into various subtypes based on gene expression profiles or histopathological features. We have explored the prevalence of cells with different CD44/CD24 phenotypes within breast cancer subtypes.', 'Double-staining immunohistochemistry was used to quantify CD44 and CD24 expression in 240 human breast tumors for which information on other tumor markers and clinical characteristics was available. Gene expression data were also accessible for a cohort of the material.', 'A considerable heterogeneity in CD44 and CD24 expression was seen both between and within tumors. A complete lack of both proteins was evident in 35% of the tumors, while 13% contained cells of more than one of the CD44+/CD24-, CD44-/CD24+ and CD44+/CD24+ phenotypes. CD44+/CD24- cells were detected in 31% of the tumors, ranging in proportion from only a few to close to 100% of tumor cells. The CD44+/CD24- phenotype was most common in the basal-like subgroup--characterized as negative for the estrogen and progesterone receptors as well as for HER2, and as positive for cytokeratin 5/14 and/or epidermal growth factor receptor, and particularly common in BRCA1 hereditary tumors, of which 94% contained CD44+/CD24- cells. The CD44+/CD24- phenotype was surprisingly scarce in HER2+ tumors, which had a predominantly CD24+ status. A CD44+/CD24- gene expression signature was generated, which included CD44 and alpha6-integrin (CD49f) among the top-ranked overexpressed genes.\Question: Does the CD44+/CD24- phenotype is enriched in basal-like breast tumors?
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We demonstrate an association between basal-like and particularly BRCA1 hereditary breast cancer and the presence of CD44+/CD24- cells. Not all basal-like tumors and very few HER2+ tumors, however, contain CD44+/CD24- cells, emphasizing that a putative tumorigenic ability may not be confined to cells of this phenotype and that other breast cancer stem cell markers remain to be identified.


question:
Context: Provocative clinical tests are often performed in the diagnosis of ulnar neuropathy at the elbow (UNE) although the evidence for the usefulness of these tests is limited. The aim of this study was to determine the diagnostic value of provocative clinical tests in the diagnosis of UNE in a relevant spectrum of patients and controls.', "A prospective cohort study was performed in consecutive patients clinically suspected of having UNE. All patients underwent a neurological examination and four commonly used provocative clinical tests (Tinel's test, flexion compression test, palpating for local ulnar nerve tenderness and nerve thickening). Subsequently, in all patients a reference standard test comprising electrophysiological studies and neurosonography was independently assessed.", "192 eligible patients completed the study protocol. UNE was diagnosed in 137 and an alternative diagnosis was made in 55 patients. The sensitivity, specificity, and positive and negative predictive values were as follows: Tinel's test 62%, 53%, 77% and 30%; flexion compression test 61%, 40%, 72% and 29%; palpating for nerve thickening 28%, 87%, 84% and 33%; and palpating for nerve tenderness 32%, 80%, 80% and 32%. Logistic regression and receiver operating characteristic curves showed that the added value of one or more provocative tests over routine clinical examination is minimal.\Question: Is the diagnostic value of provocative clinical tests in ulnar neuropathy at the elbow marginal?
answer:
The diagnostic value of provocative clinical tests in UNE is poor.


question:
Context: Chronic antibiotic-refractory pouchitis (CARP) occurs more frequently in patients with ileal pouch-anal anastomosis (IPAA) with concomitant autoimmune disorders. The aim of this study was to assess the overlap between dysregulated immune features in patients with IPAA and their association with CARP.', 'We identified 150 symptomatic patients with IPAA who met inclusion criteria, including measurement of select autoimmune serology. Demographic and clinical variables were compared between patients with and without CARP.', 'Autoimmune thyroid disease was more frequent among patients with CARP. The frequency of primary sclerosing cholangitis (16.7% versus 5.3%; P = 0.04) and serum positivity for microsomal antibody (25% versus 6.1%, P = 0.003) were significantly greater in patients with CARP compared with non-CARP patients, respectively. Increased tissue infiltration by IgG4-expressing plasma cells was detected in 17 of 31 patients (54.8%) in the CARP group as compared with 10/67 (14.9%) in the non-CARP group (P = 0.0001). Forty-seven percent of patients in the CARP group versus 22.8% in the non-CARP group had at least 2 immune features (P = 0.019). Among patients with IgG4 histology, 87% of patients in the CARP group versus 60% in the non-CARP group had at least 1 immune marker (P = 0.004). On multivariate analysis, microsomal antibody expression (odds ratio, 6.8; 95% confidence interval, 1.3-42.6; P = 0.02) and increased IgG4-expressing plasma cells tissue infiltration (odds ratio, 9.6; 95% confidence interval, 3.2-32.6, P = 0.0001) were risk factors for CARP.\Question: Are autoimmune features associated with chronic antibiotic-refractory pouchitis?
answer:

There is marked overlap of certain immune markers in patients with pouch dysfunction, especially those with CARP. Microsomal antibody expression and elevated IgG4-positive plasma cell infiltration were independent risk factors for CARP.