Test–retest repeatability of [18F]Flortaucipir PET in Alzheimer’s disease and cognitively normal individuals

The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [¹⁸F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [¹⁸F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr_80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr_80–100 and SUVr_110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods.     

Tspan8 is expressed in breast cancer and regulates E-cadherin/catenin signalling and metastasis accompanied by increased circulating extracellular vesicles

Tspan8 exhibits a functional role in many cancer types including pancreatic, colorectal, oesophagus carcinoma, and melanoma. We present a first study on the expression and function of Tspan8 in breast cancer. Tspan8 protein was present in the majority of human primary breast cancer lesions and metastases in the brain, bone, lung, and liver. In a syngeneic rat breast cancer model, Tspan8⁺ tumours formed multiple liver and spleen metastases, while Tspan8⁻ tumours exhibited a significantly diminished ability to metastasise, indicating a role of Tspan8 in metastases. Addressing the underlying molecular mechanisms, we discovered that Tspan8 can mediate up-regulation of E-cadherin and down-regulation of Twist, p120-catenin, and β-catenin target genes accompanied by the change of cell phenotype, resembling the mesenchymal–epithelial transition. Furthermore, Tspan8⁺ cells exhibited enhanced cell–cell adhesion, diminished motility, and decreased sensitivity to irradiation. As a regulator of the content and function of extracellular vesicles (EVs), Tspan8 mediated a several-fold increase in EV number in cell culture and the circulation of tumour-bearing animals. We observed increased protein levels of E-cadherin and p120-catenin in these EVs; furthermore, Tspan8 and p120-catenin were co-immunoprecipitated, indicating that they may interact with each other. Altogether, our findings show the presence of Tspan8 in breast cancer primary lesion and metastases and indicate its role as a regulator of cell behaviour and EV release in breast cancer. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.     

The impact of descriptive norms on motivation to participate in cancer screening – Evidence from online experiments

ObjectiveThe current study tested in two online experiments whether manipulating normative beliefs about cancer screening uptake increases intention to attend colorectal screening among previously disinclined individuals.Methods2461 men and women from an Internet panel (Experiment 1 N = 1032; Experiment 2, N = 1423) who initially stated that they did not intend to take up screening were asked to guess how many men and women they believe to get screened for colorectal cancer. Across participants, we varied the presence/absence of feedback on the participant’s estimate, as well as the stated proportion of men and women doing the screening test.ResultsAcross the two experiments, we found that receiving one of the experimental messages stating that uptake is higher than estimated significantly increased the proportion of disinclined men and women becoming intenders. While, we found a positive relationship between the communicated uptake and screening intentions, we did not find evidence that providing feedback on the estimate has an added benefit.ConclusionScreening intention can be effectively manipulated through a high uptake message.Practice implicationsCommunication of high screening uptake is an easy and effective way to motivate disinclined individuals to engage in colorectal cancer screening.     

Chronic mechanical trauma in the aetiology of oro-pharyngeal carcinoma.

Tumours of the oral cavity and the oropharynx account for 12% of the malignancies in our patient material. The group of patients included a high percentage of smokers (83%), heavy drinkers and persons neglectful of oral hygiene. The majority of the patients mainly male were labourers or (small) farmers. In contrast to other reports in the literature, chronic mechanical trauma due to sharp remaining teeth, less than ideal fillings, badly fitting dentures or unsuitable denture-bearing tissue, and loose anchoring attachments were frequently present. Commensurate with the clinical findings, permanent damage to the covering squamous epithelium was demonstrated histologically. In addition to all forms of inflammation, parakeratosis and hyperkeratosis, dysplasia, including carcinoma in situ, and manifest carcinomas also presented. Surface-inert dentures and regular oral hygiene must therefore be considered an important requirement for the prevention of oral-cavity carcinoma.     

A survey of members of the American Academy of Pediatric Dentistry on their use of behavior management techniques

PURPOSE: The objective of this study was to survey members of the American Academy of Pediatric Dentistry (AAPD) regarding their use of behavior management techniques. METHODS: Surveys were mailed to 4,180 members, with a follow-up mailing to nonrespondents 2 months later. The survey contained items on demographic variables and use (current, past, and future) of communicative and pharmacologic techniques. Information was also obtained on informed consent, parental presence in the operatory, and parenting styles. RESULTS: Survey response was 66%. Communicative techniques are widely used, with the exception of the hand-over-mouth exercise (HOME). Immobilization for sedated and nonsedated children and pharmacologic techniques are used by a majority or near majority of respondents. Little change was reported in technique use over time, except that 50% of respondents indicated they use HOME less now than 5 years ago, and 24% plan to use it less over the next 2 to 3 years. Parental presence in the operatory appeared to be a common practice for some procedures and for children with special health care needs. The majority of respondents believed that parenting styles had changed in ways that adversely impacted children's behavior in the dental setting. CONCLUSIONS: Most practitioners have not changed their use of behavior management techniques in recent years, nor do they plan to change their use of them in the near future. HOME was the exception to these trends.