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Medical imaging involving the use of ionizing radiat ion has brought enormous benefi ts to society and patients. In the past several decades, exposure to medical radiation has increased markedly, driven primarily by the use of computed tomography. Ionizing radiation has been linked to carcinogenesis. Whether low-dose medical radiation exposure will result in the development of malignancy is uncertain. This paper reviews the current evidence for such risk, and aims to inform the gastroenterologist of dosages of radiation associated with commonly ordered procedures and diagnostic tests in clinical practice. The use of medical radiation must always be justifi ed and must enable patients to be exposed at the lowest reasonable dose. Recommendations provided herein for minimizing radiation exposure are based on currently available evidence and Working Party expert consensus.

Previous research showed an effect of words’ rated body-object interaction (BOI) in children’s visual word naming performance, but only in children 8 years of age or older (Wellsby & Pexman, 2014a). In that study, however, BOI was established using adult ratings. Here we collected ratings from a group of parents for children’s body-object interaction experience (child-BOI). We examined effects of words’ child-BOI and also words’ imageability on children’s responses in an auditory word naming task, which is suited to the lexical processing skills of younger children. We tested a group of 54 children aged 6-7 years and a comparison group of 25 adults. Results showed significant effects of both imageability and child-BOI on children’s auditory naming latencies. These results provide evidence that children younger than 8 years of age have richer semantic representations for high imageability and high child-BOI words, consistent with an embodied account of word meaning.

Anal condyloma acuminata and anal dysplasia are human papillomavirus-related intraepithelial lesions that are precursors of anal squamous cell cancer. Risk factors include immunosuppression for patients who have inflammatory bowel disease, cervical cancer, human immunodeficiency virus, a history of solid organ transplantation, as well as viral transmission by person-to-person contact. Assessment includes disease-specific history and physical examination, selected tests, and biopsy of suspicious lesions. Treatment includes antiviral agents, anticytotics, strong acid, or ablation using a variety of techniques. Vaccine prophylaxis against four types of human papillomavirus is available. This chapter discusses infection, diagnosis, and treatment of condyloma acuminata and anal dysplasia.

Aim Anal intraepithelial neoplasia precedes the development of anal squamous cell carcinoma. Detection of the lesion is essential to management. This paper describes a prospective study to detect and ablate anal squamous intraepithelial lesions (SILs) using white light narrow band imaging (NBI) and NBI with acetic acid (NBIA). Method Sixty patients with abnormal anal cytology and risk factors for anal dysplasia underwent examination of the anoderm with a high definition gastroscope and NBIA. Targeted biopsies were taken and the lesions were ablated and characterized histopathologically. Visualization of the anal transitional zone was facilitated by retroflexion and examination through a disposable anoscope. Results Targeted biopsies were taken from lesions in 58 patients. No lesion was seen in two patients. Histopathology showed SIL in 48 (80.0%) of 60 biopsies. One biopsy showed lymphoid aggregates. Biopsies in nine (15%) of the 60 patients showed normal mucosa. Lesions were seen in white light in 27 (45%) of the 60 cases, NBI in 39 (65%) and NBIA in 57 (95%). There was no major morbidity. Sensitivity analysis showed that all methods were significantly different from each other. Conclusion Anal SIL in the anal transitional zone and anal canal can be identified by NBIA. Patient selection influences findings. Limitations include small sample size and non‐randomization.

In humans, parenteral nutrition leads to a decrease in mucosal thickness, a decrease in villus height, and a decrease in mucosal proliferation rate. If it is possible to provide nutrition enterally this is the method of choice. The introduction of enteral feeding tubes that can be placed endoscopically has revolutionized human nutrition in many clinical scenarios. Patients who are unable to take in their daily nutritional needs by mouth – whether because of trauma, burns, or surgical resection of the small bowel – can now receive their daily nutrition in a formula made for their individual requirements. This can be done for shorter or longer periods of time without some of the complications such as line sepsis seen in patients who must utilize central lines for nutrition. Tubes can be placed endoscopically into the stomach, the jejunum, the esophagus, and the cecum or appendix. This chapter discusses the development, as well as the uses, of these different types of feeding tubes.

We have shown that the sequence of the hemagglutinin gene of influenza virus can be determined from virus recovered from nasopharyngeal swabs collected for diagnostic purposes by using the polymerase chain reaction (PCR) to amplify cDNA made by reverse transcriptase (Rajakumar et al. 1990). These studies suggest that PCR might be used in the routine diagnosis of influenza. Our experience indicates that the success of such a procedure would depend on (1) obtaining adequate cDNA synthesis from all virus strains encountered in clinical samples, (2) eliminating problems of DNA contamination, (3) ensuring production of amplified DNA from the appropriate influenza virus genes, and (4) developing appropriate methods to identify virus strains. The feasibility of such an approach to diagnosis is discussed with respect to sensitivity, reliabil ity, virus strain identification, speed, and cost.

Incubating 32P-labeled fat cells with insulin increased by as much as 80-fold the amount of 32Pi in a soluble species of apparent Mr 62,000. This species, designated isp62, was specifically immunoprecipitated from cellular extracts with a monoclonal antibody against the type II regulatory subunit (RII) of cAMP-dependent protein kinase. Fat-cell RII, purified from extracts with cAMP-Sepharose or labeled with 8-azido [32P]cAMP, had an apparent Mr 51,000. Peptide mapping indicated that isp62 and adipocyte RII were different proteins. When cells were metabolically labeled with [35S]methionine, insulin stimulated the appearance of 35S-labeled isp62, indicating that the hormonal effect involves generation of the protein. The insulin-induced increase in isp62 could be observed within 1 min, occurred with physiological concentrations of the hormone, and was rapidly reversible. The increase in isp62 was unaffected by cycloheximide, indicating that insulin stimulates the posttranslational processing of a precursor, rather than de novo synthesis of the protein.

Mitogens generally stimulate human IgG subclass production in amounts proportional to their abundance in serum (IgG1 greater than IgG2 greater than IgG3 greater than IgG4). We report here that a combination of Staphylococcus aureus Cowan strain I and pokeweed mitogen consistently stimulates human peripheral blood lymphocytes in vitro to preferentially produce more IgG1 and IgG3 than IgG2. This preferential stimulation can be measured by increases in the number of immunoblasts (cells with detectable cytoplasmic immunoglobulin) as well as in secreted immunoglobulin. The preferential stimulation pattern is established by the fourth day of culture and is maintained at least until the tenth day. Removal of T cells and subsequent stimulation of B cells with S. aureus Cowan I and interleukin 1 (IL-1) interleukin 2 (IL-2), interleukin 4 (IL-4), or interferon-gamma (IFN-gamma) failed to enhance any IgG subclass production, indicating the requirement for multiple lymphokines in IgG subclass production. The significance of these findings is discussed with respect to B-cell regulatory molecules and the coordinate expression of IgG subclasses.