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Using the response to Mycobacterium butyricum as the test-immune response, the main goal of this study was to demonstrate the suitability of the growing feather (GF) as a dermal test site and window into in vivo cellular/tissue responses (US-Patent 8,216,551). Using M. butyricum immunized chickens, the specific objectives were to: 1) compare the leukocyte infiltration response to intra-dermally injected M. butyricum in GF, wattles, and wing webs; 2) use GF as the test site to monitor leukocyte response profiles to recall antigen in the same individuals; and 3) gain new knowledge regarding the local response to M. butyricum in chickens. For objective 1, chickens were euthanized for tissue collection at 4 to 6, 24, 48, and 72 h after intra-dermal antigen injection. Leukocyte infiltration profiles were determined using immunochemical and conventional histology. Data from this study established the similarities between the cellular response in GF, wattles, and wing webs and uncovered many advantages of working with GF. For objective 2, antigen was injected into multiple GF per individual. GF were collected before and at 0.25, 1, 2, 3, and 7 d post injection and processed for cell population analysis by flow cytometry. Advantages of the approach used in objective 2 included a technically easier, more comprehensive, and more objective leukocyte profile analysis; same-day data acquisition; and, most importantly, easy, minimally invasive sample collection from the same individual throughout the study. Both studies contributed new knowledge regarding the local cutaneous response to M. butyricum in M. butyricum immunized chickens and confirmed the cell-mediated nature of the immune response to M. butyricum (e.g., elevated levels [P < 0.05] of T cells [CD4+ and CD8+], macrophages and MHC class II+-cells on days one to 3 post injection in M. butyricum- compared to PBS-injected tissues). The use of GF as an "in vivo test tube" to monitor local innate and adaptive immune activities will find direct application in vaccine development, as well as in the assessment and optimization of immune system development and function in poultry. [ABSTRACT FROM AUTHOR]

Aberrant activation of Wingless-type (Wnt)/β-catenin signaling is widespread in human cervical cancer. However, the underlying mechanisms of Wnt activation and the therapeutic potential of Wnt inhibition remain largely unknown. Here, we demonstrate that the Wnt inhibitory factor 1 (WIF1), a secreted Wnt antagonist, is downregulated in all human primary cervical tumors and cell lines analyzed. Our data reveal that WIF1 downregulation occurs due to promoter hypermethylation and is an early event in cervical oncogenesis. WIF1 re-expression upon 5-aza-2′-deoxycytidine treatment or WIF1 gene transfer induces significant apoptosis and G2/M arrest, and inhibits cervical cancer cell proliferation in vitro. Consistent with this, treatment of established mice tumor xenografts with peritumoral WIF1 gene transfer results in a significant inhibition of cancer growth and invasion. WIF1 treatment causes a significant decrease in intracellular WNT1 and TCF-4 proteins revealing novel Wnt-regulatory mechanisms. Thus, WIF1 causes a major cellular re-distribution of β-catenin and a significant inhibition of the Wnt/β-catenin pathway in tumor cells, as documented by a remarkable reversion in the expression of Wnt/β-catenin transcriptional target genes (E-cadherin, c-Myc, cyclin D1, CD44 and VEGF). Consequently, multiple critical events in tumor progression and metastasis such as cell proliferation, angiogenesis and invasion were inhibited by WIF1. In addition, WIF1 modulated the expression of specific anti-apoptotic and apoptotic proteins, thereby inducing significant apoptosis in vivo. Our findings demonstrate for the first time that WIF1 downregulation by epigenetic gene silencing is an important mechanism of Wnt activation in cervical oncogenesis. Of major clinical relevance, we show that peritumoral WIF1 gene transfer reduces not only cancer growth but also invasion in well-established tumors. Therefore, our data provide novel mechanistic insights into the role of WIF1 in cervical cancer progression, and the important preclinical validation of WIF1 as a potent drug target in cervical cancer treatment. [ABSTRACT FROM AUTHOR]

Computed tomography is being increasingly used for the evaluation of patients with vague abdominal symptoms, and may provide the initial opportunity to detect and characterize tumours of the small bowel. The recognition of imaging features on CT allows distinction to be made between benign and malignant neoplasms. Multidetector row CT (MDCT) provides high-resolution imaging and helps in precise localization and characterization of lesions. This article illustrates the imaging appearances of small bowel tumours on MDCT and demonstrates the usefulness of multiplanar reformatting (MPR) in the diagnosis and categorization of these tumours. [Copyright &y& Elsevier]

In recent years there has been a marked increase in the incidence of pseudomembranous colitis (PMC). PMC is more common in patients over 65 years of age and can cause significant morbidity. The purpose of this article is to review the imaging features of PMC on plain radiography, sonography, computed tomography (CT), scintigraphy and magnetic resonance imaging (MRI). It is important to recognize the imaging findings of PMC using different imaging methods and encourage urgent confirmation of the diagnosis serologically, as the differential includes other fulminant colitides for which colectomy may be the required. Awareness of the spectrum of imaging findings of PMC can help radiologists make the primary or incidental diagnosis of PMC. [Copyright &y& Elsevier]

Aim: To determine the accuracy of high-resolution magnetic resonance enterography (HR-MRE) against surgical and histopathology standards in Crohn's disease, and to determine quantitative MRE findings that can differentiate minor from advanced bowel inflammation. Materials and methods: Forty-nine consecutive patients who underwent 51 surgical procedures underwent standard MRE and HR-MRE prior to surgery. MRE images were assessed for superficial ulcers, deep ulcers, abscesses, fistulae, and strictures. Quantitative MRE parameters, such as mural thickness, enhancement ratios (ER) of the abnormal bowel, mesentery (ME), and normal bowel (controls), were recorded. MRE findings were compared with surgical and histological results to obtain sensitivity, specificity, and accuracy. Grading of inflammation was compared with MRE parameters for correlation and discriminating power. Results: The sensitivities and specificities of MRE and HR-MRE enterography in the detection of abnormal segments were 0.82 and 0.95 versus 0.86 and 0.95 respectively. HR-MRE was significantly more sensitive than MRE and HR-MRE in the detection of superficial and deep ulcers, fistulae, and abscesses (0.5 versus 0.69; 0.69 versus 0.94; 0.76 versus 0.95; 0.77 versus 1.0, respectively). Mural thickness, ER, and ME had positive correlation with higher grades of inflammation(r = 0.8, 0.66, 0.42, respectively). Regression analysis showed deep and superficial ulcers, ER > 1.85 and mural thickness >4.5 mm were independent predictors of advanced inflammation. Conclusion: HR-MRE has significantly greater diagnostic accuracy as compared to MRE in the diagnosis of bowel ulceration, fistulae and abscesses. Bowel ulcers, mural enhancement ratio >1.85 are strong predictors of advanced inflammation. [Copyright &y& Elsevier]

The purpose of this article is to review the imaging findings of various infections affecting the gastrointestinal tract. Barium examinations, computed tomography (CT), magnetic resonance imaging (MRI), and ultrasonography all play an important role in the diagnostic workup of gastrointestinal tract infections. Knowledge of differential diagnosis, sites of involvement, and typical imaging features of different infections can help in accurate diagnosis and guide treatment. [Copyright &y& Elsevier]

The purpose of this article is to provide a comprehensive review of the imaging findings of various parasitic infestations and other miscellaneous infections affecting the gastrointestinal tract. Barium examinations play an important role in the diagnostic workup of parasitic intestinal infections. Knowledge of differential diagnosis, sites of involvement, and imaging features of different infections and infestations can help in accurate diagnosis and guide treatment. [Copyright &y& Elsevier]