Evaluation of bronchial challenge test results for use in assessment of paediatric eczema: a retrospective series.

BACKGROUND: Atopic dermatitis (AD), asthma, and allergic rhinitis are associated diseases involved in the atopic march. The bronchial challenge test (BCT) is a tool that evaluates airway hyperresponsiveness in patients with asthma. This study aimed to evaluate whether a positive BCT result is useful in assessment of paediatric AD. METHODS: This retrospective case series included 284 patients with AD who had BCT results. Clinical information and laboratory parameters were reviewed, including AD severity (using the SCORing Atopic Dermatitis [SCORAD]), skin hydration, and transepidermal water loss. RESULTS: Of the 284 patients who had BCT, 106 had positive BCT results and 178 had negative BCT results. A positive BCT result was associated with a history of asthma (P<0.0005), sibling with asthma (P=0.048), serum immunoglobulin E (P=0.045), eosinophil count (P=0.017), and sensitisation to food allergens in the skin prick test (P=0.027). There was no association between a positive BCT result and personal allergic rhinitis, parental atopy, sibling allergic rhinitis or AD, skin prick response to dust mites, objective SCORAD score, skin hydration, transepidermal water loss, exposure to smoking, incense burning, cat or dog ownership, or AD treatment aspects (eg, food avoidance and traditional Chinese medicine). Logistic regression showed significant associations of a positive BCT result with a history of asthma (adjusted odds ratio=4.05; 95% confidence interval=1.92-8.55; P<0.0005) and sibling atopy (adjusted odds ratio=2.25; 95% confidence interval=1.03-4.92; P=0.042). CONCLUSIONS: In patients with paediatric AD, a positive BCT result was independently and positively associated with personal history of asthma and sibling history of atopy, but not with any other clinical parameters.

Leadership and mentoring in medical physics: The experience of a medical physics international mentoring program.

Mentoring aims to improve careers and create benefits for the participants' personal and professional lives. Mentoring can be an individual or a shared experience for a group, while the mentor's role remains the same in both models. Mentors should increase confidence, teach, inspire, and set examples, helping the mentees to mould their path, contributing to the pursuit of their personal and professional goals. This study aims to report on the experience of early-career medical physics professionals and postgraduate students participating in a global mentoring program and to assess the impact of this activity on their professional development. The objectives of this mentoring program are to develop leadership roles among young medical physicists and to provide guidance and support. An online questionnaire was administered to the mentee participants. The analysis of their responses is reported in this work and the current status of the programme was examined using a SWOT analysis. In general, the mentoring experience had a positive impact on the mentees. The mentors were found especially helpful in the decision-making situations and in other conflicts that may arise with career development. Additionally, the mentees felt that mentoring contributed to the development of leadership skills required for the job market and assist in personal development. This paper concludes that participation of young medical physicists in a mentoring group program is beneficial to their career and therefore should be encouraged.

Investigation of an SFOV hybrid gamma camera for thyroid imaging.

The Hybrid Compact Gamma Camera (HCGC) is a small field of view (SFOV) portable hybrid gamma-optical camera intended for small organ imaging at the patient bedside. In this study, a thyroid phantom was used to determine the suitability of the HCGC for clinical thyroid imaging through comparison with large field of view (LFOV) system performance. A direct comparison with LFOV contrast performance showed that the lower sensitivity of the HCGC had a detrimental effect on image quality. Despite this, the contrast of HCGC images exceeded those of the LFOV cameras for some image features particularly when a high-resolution pinhole collimator was used. A clinical simulation showed that thyroid morphology was visible in a 5 min integrated image acquisition with an expected dependency on the activity within the thyroid. The first clinical use of the HCGC for imaging thyroid uptake of (123)I is also presented. Measurements indicate that the HCGC has promising utility in thyroid imaging, particularly as its small size allows it to be brought into closer proximity with a patient. Future development of the energy response of the HCGC is expected to further improve image detectability.

An EMT spectrum defines an anoikis-resistant and spheroidogenic intermediate mesenchymal state that is sensitive to e-cadherin restoration by a src-kinase inhibitor, saracatinib (AZD0530).

The phenotypic transformation of well-differentiated epithelial carcinoma into a mesenchymal-like state provides cancer cells with the ability to disseminate locally and to metastasise. Different degrees of epithelial-mesenchymal transition (EMT) have been found to occur in carcinomas from breast, colon and ovarian carcinoma (OC), among others. Numerous studies have focused on bona fide epithelial and mesenchymal states but rarely on intermediate states. In this study, we describe a model system for appraising the spectrum of EMT using 43 well-characterised OC cell lines. Phenotypic EMT characterisation reveals four subgroups: Epithelial, Intermediate E, Intermediate M and Mesenchymal, which represent different epithelial-mesenchymal compositions along the EMT spectrum. In cell-based EMT-related functional studies, OC cells harbouring an Intermediate M phenotype are characterised by high N-cadherin and ZEB1 expression and low E-cadherin and ERBB3/HER3 expression and are more anoikis-resistant and spheroidogenic. A specific Src-kinase inhibitor, Saracatinib (AZD0530), restores E-cadherin expression in Intermediate M cells in in vitro and in vivo models and abrogates spheroidogenesis. We show how a 33-gene EMT Signature can sub-classify an OC cohort into four EMT States correlating with progression-free survival (PFS). We conclude that the characterisation of intermediate EMT states provides a new approach to better define EMT. The concept of the EMT Spectrum allows the utilisation of EMT genes as predictive markers and the design and application of therapeutic targets for reversing EMT in a selective subgroup of patients.

A low-cost phantom for simple routine testing of single photon emission computed tomography (SPECT) cameras.

A simple sphere test phantom has been developed for routine performance testing of SPECT systems in situations where expensive commercial phantoms may not be available. The phantom was based on a design with six universal syringe hubs set in the frame to support a circular array of six glass blown spheres of different sizes. The frame was then placed into a water-filled CT abdomen phantom and scanned with a triple head camera system (Philips IRIX, USA). Comparison was made with a commercially available phantom (Deluxe Jaszczak phantom). Whereas the commercial phantom demonstrates cold spot resolution, an important advantage of the sphere test phantom was that hot spot resolution could be easily measured using almost half (370MBq) of the activity recommended for use in the commercial phantom. Results showed that the contrast increased non-linearly with sphere volume and radionuclide concentration. The phantom was found to be suitable as an inexpensive option for daily performance tests.

Bone quality and bone strength in BXH recombinant inbred mice.

The relationship between bone quality and strength was studied in 11 BXH recombinant inbred (RI) strains of mice. The bone quality parameters studied were bone mineralization, microhardness, architecture, and connectivity. Previous studies have demonstrated considerable variability in bone density, biomechanical properties, and microstructure among inbred strains of mice. In particular, C3H/HeJ (C3H) mice exhibit thicker femoral and vertebral cortices and fewer trabeculae in the vertebral body compared with C57BL/6J (B6) mice, despite having similar vertebral bone strength. A set of RI mouse strains has been generated from B6 and C3H (denoted BXH) in an attempt to isolate genetic regulation of numerous traits, including bone. The objective of this study was to investigate relationships among bone quality and bone strength in femurs and vertebrae among BXH RI mice. The study involved 11 BXH RI strains of female mice (n = 5-7) as well as the B6 and C3H progenitor strains. Parameters contributing to bone quality were evaluated, including BMD, bone mineralization, microhardness, architecture, and connectivity. There was a strong correlation between femoral and vertebral BMD in all strains (P < 0.001) except in BXH-9 and -10 (P < 0.001). Within the vertebrae, cortical bone was more mineralized than trabecular bone, and a strong correlation existed between the two (P < 0.001). However, cortical microhardness did not differ from trabecular microhardness. Cortical bone was more mineralized in the femur than in the vertebrae and significantly harder, by 30%. There was a wide range in trabecular connectivity, architecture, and femur geometry among BXH RI strains. BMD explained 43% of vertebral bone strength but only 11% of femoral bone strength. Trabecular connectivity explained an additional 8% of vertebral strength, while mineralization and femur geometry explained 7% and 50% of femoral strength, respectively. Different bone quality parameters had varying influences on bone mechanical properties, depending on bone site. BMD may play a larger role in explaining bone strength in the vertebrae than in the femur. Moreover, cortical bone in the femur is harder than in vertebrae. The control of cortical bone material properties may be site-dependent.

Stress proteins induced by exposure to sublethal levels of heavy metals in sea bream (Sparus sarba) blood cells.

Blood cells freshly collected from silver sea bream (Sparus sarba) were exposed in vitro to different sublethal concentrations of cadmium(II), lead(II) or chromium(VI). HSP70 stress proteins were significantly overexpressed after exposure to metal concentration as low as 0.1 microM. Under our experimental conditions, no overexpression of metallothioneins in blood cells was evidenced. Our results show that fish blood cells may constitute an interesting biological model for experimental and applied toxicology, especially in the case of environmental pollution.

Association between fluoride, magnesium, aluminum and bone quality in renal osteodystrophy.

INTRODUCTION: Trace elements are known to influence bone metabolism; however, their effects may be exacerbated in renal failure because dialysis patients are unable to excrete excess elements properly. Our study correlated bone quality in dialysis patients with levels of bone fluoride, magnesium, and aluminum. A number of studies have linked trace elements, including fluoride, magnesium, and aluminum, to the development of renal osteodystrophy (ROD). However, little is known about the relationship between trace elements and changes in bone quality in ROD patients. The purpose of this study was to examine bone quality in ROD patients, and correlate differences in bone quality to trace element concentrations in bone. Bone quality encompasses parameters that contribute to the mechanical integrity of the bone. METHODS: One hundred fifty-three anterior iliac crest bone biopsies from patients with ROD were examined and subdivided into five groups based on the pathological features. Parameters contributing to bone quality, such as bone structure and remodeling, connectivity, mineralization, and microhardness, were assessed and correlated to bone chemical composition. In addition, clinical symptoms of ROD were assessed and correlated with bone composition. RESULTS AND CONCLUSIONS: There were no differences in bone architecture between the different ROD bone groups; however, differences in bone mineralization and microhardness were observed. Increase in bone fluoride was associated with increased osteoid parameters and decreased bone microhardness. Bone mineralization and microhardness decreased with increasing bone magnesium content and intact parathyroid hormone (PTH) level. Moreover, bone magnesium increased with intact PTH levels. The relationship between PTH, bone magnesium, mineralization, and microhardness was primarily observed in aplastic bone disorder. Furthermore, bone magnesium and aluminum contents were positively associated with bone pain and proximal myopathy in these patients. Most importantly, fluoride, magnesium, and aluminum showed significant correlations with one another. These results suggested that in ROD, bone fluoride may diminish bone microhardness by interfering with mineralization. Magnesium may be involved in the suppression of PTH secretion, lowering bone turnover thus leading to an increase in bone mineralization profile and microhardness in aplastic bone disorder. The effects of fluoride and magnesium on bone quality may be exacerbated by their interaction with aluminum.