IgG4-Related Disease Presenting as a Solitary Neck Mass.

IgG4-related disease is a newly recognized entity associated with autoimmune conditions involving almost every organ system. It is characterized by elevated serum IgG4 as well as mass like tissue infiltration by IgG4-positive plasma cells. Imaging findings are nonspecific, vary depending on the site of disease, and include mass like enlargement of the salivary or lacrimal glands and enlarged lymph nodes. Radiographic findings often mimic malignancy, necessitating tissue sampling to confirm the diagnosis. Distinguishing IgG4-related disease from malignancy is important as IgG4 responds well to steroids and conservative management.

Development of the AMSER standardized examinations in radiology for medical students.

RATIONALE AND OBJECTIVES: The variability in medical imaging evaluation across US medical schools inspired leading radiology student educators to develop the Alliance of Medical Student Educators in Radiology (AMSER) Standardized Exam (SE). This examination tests the understanding of essential material and concepts which are endorsed by the AMSER National Medical Student Curriculum in Radiology. MATERIALS AND METHODS: The AMSER Electronics Committee developed and deployed the AMSER SE using Radiology ExamWeb (REW), a previously-developed databank of imaging questions. The Committee created an examination blueprint that placed emphasis on effective use of medical imaging and less emphasis on image interpretation. Question items correlating to the blueprint were used from the REW databank to draft AMSER SE version 1, which was piloted in early 2012. Item performance was then analyzed, and the exam was revised. After national deployment, a subsequent revision was performed 1 year later. AMSER SE version 2, developed in a similar manner, was released in early 2013 and will go through a similar process of revision. A 20-question Practice Exam was also developed. RESULTS: Since national deployment, more than 1400 students, in over 22 institutions, have taken the AMSER SEs. CONCLUSIONS: The collaborative project of the AMSER Electronics Committee has resulted in the successful national deployment of two examinations using questions that have been validated and based on the AMSER peer-reviewed national curriculum. We hope that this assessment tool will help drive a more uniform approach to curriculum development, promoting more effective and safe use of medical imaging. This step should also help promote the value radiologists bring to the patient care arena.

Daughter cyst sign.

The daughter cyst sign is a specific indicator of an uncomplicated ovarian cyst and pathologically represents a stimulated ovarian follicle. This finding must be differentiated from an ectopic pregnancy in a patient who has the potential to become pregnant. We report an uncomplicated ovarian cyst in a 3-year-old female with McCune-Albright syndrome and precocious puberty mimicking an ectopic pregnancy.

Embryo dose estimates in body CT.

OBJECTIVE: The purpose of this article is to develop a method for estimating embryo doses in CT. MATERIALS AND METHODS: Absorbed doses to the uterus (embryo) of a 70-kg woman were estimated using the ImPACT CT Patient Dosimetry Calculator. For a particular CT scan length, relative uterus doses and normalized plateau uterus doses were determined for a range of commercial CT scanners. Patient size characteristics were obtained from cross-sectional axial images of 100 consecutive patients (healthy women undergoing unenhanced pelvic CT examinations). For each patient, the diameter of a water cylinder with the same mass as the patient's pelvis was computed. Relative dose values were generated for cylinder diameters ranging from 16 to 36 cm at x-ray tube voltages between 80 and 140 kV. RESULTS: Values of relative uterus dose increased monotonically with increasing scan length, independently of scanner model, and reached a plateau for scan lengths greater than approximately 50 cm. The average normalized plateau uterus dose for all scanners was approximately 1.4 and showed interscanner differences of less than 10% for modern scanners operated at 120 kV. Normalized plateau doses show little dependence on the x-ray tube voltage used to perform the CT examination. Our results show that the uterus dose estimate in an abdominal or pelvis CT examination performed on a 70-kg patient is about 40% higher than the reported value of the volume CT dose index (CTDI(vol)). The pelvis of a 70-kg patient may be modeled as a water cylinder with a diameter of 28 cm and has an average anteroposterior dimension of 22 cm. For constant CT technique factors, embryo dose estimates for a 45-kg patient would be approximately 18% higher than those for a 70-kg patient, whereas the corresponding dose estimates in a 120-kg patient would be approximately 37% lower. CONCLUSION: Embryo doses can be estimated using relative uterus doses, normalized plateau uterus doses, and CTDI(vol) data with correction factors for patient size.

Cortisol and alpha amylase reactivity and timing of puberty: vulnerabilities for antisocial behaviour in young adolescents.

The theoretical framework proposed that cortisol and saliva alpha amylase (sAA) reactivitiy are vulnerabilities for antisocial behaviour. These indices of hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal-medulary (SAM) components of the stress system, respectively, were considered vulnerabilities that also interact with the putative stressful transition of timing of puberty to predispose adolescents toward antisocial behaviour. The sample consisted of 8- to-13-year-old boys and girls (N=135) and a parent. For boys, timing of puberty moderated the association between cortisol and sAA reactivity and antisocial behaviour. Higher cortisol reactivity in later timing boys was related to a composite index of antisocial behaviour and rule-breaking behaviour problems. In contrast, lower sAA reactivity and earlier timing of puberty in boys was related to rule breaking and conduct disorder symptoms. The interaction between timing of puberty and HPA or SAM regulation and timing of puberty in boys suggests that reproductive, neuroendocrine mechanisms may be involved in the extensively documented adverse consequences of off-time pubertal development.

Influence of HFE variants and cellular iron on monocyte chemoattractant protein-1.

BACKGROUND: Polymorphisms in the MHC class 1-like gene known as HFE have been proposed as genetic modifiers of neurodegenerative diseases that include neuroinflammation as part of the disease process. Variants of HFE are relatively common in the general population and are most commonly associated with iron overload, but can promote subclinical cellular iron loading even in the absence of clinically identified disease. The effects of the variants as well as the resulting cellular iron dyshomeostasis potentially impact a number of disease-associated pathways. We tested the hypothesis that the two most common HFE variants, H63D and C282Y, would affect cellular secretion of cytokines and trophic factors. METHODS: We screened a panel of cytokines and trophic factors using a multiplexed immunoassay in human neuroblastoma SH-SY5Y cells expressing different variants of HFE. The influence of cellular iron secretion on the potent chemokine monocyte chemoattractant protein-1 (MCP-1) was assessed using ferric ammonium citrate and the iron chelator, desferroxamine. Additionally, an antioxidant, Trolox, and an anti-inflammatory, minocycline, were tested for their effects on MCP-1 secretion in the presence of HFE variants. RESULTS: Expression of the HFE variants altered the labile iron pool in SH-SY5Y cells. Of the panel of cytokines and trophic factors analyzed, only the release of MCP-1 was affected by the HFE variants. We further examined the relationship between iron and MCP-1 and found MCP-1 secretion tightly associated with intracellular iron status. A potential direct effect of HFE is considered because, despite having similar levels of intracellular iron, the association between HFE genotype and MCP-1 expression was different for the H63D and C282Y HFE variants. Moreover, HFE genotype was a factor in the effect of minocycline, a multifaceted antibiotic used in treating a number of neurologic conditions associated with inflammation, on MCP-1 secretion. CONCLUSION: Our results demonstrate that HFE polymorphisms influence the synthesis and release of MCP-1. The mechanism of action involves cellular iron status but it appears there could be additional influences such as ER stress. Finally, these data demonstrate a pharmacogenetic effect of HFE polymorphisms on the ability of minocycline to inhibit MCP-1 secretion.

The stress response in adolescents with inattentive type ADHD symptoms.

OBJECTIVE: To investigate the hypothalamic pituitary adrenal (HPA) axis response to a stressor in adolescents with inattentive type attention-deficit hyperactivity disorder symptoms (ADHD-I). METHOD: Salivary cortisol was measured in threshold inattentive (TI, n = 7), moderately inattentive (MI, n = 13) and no symptom (comparison) (n = 19) groups of healthy, young adolescents, based on symptom counts, prior to and after an induced social/cognitive stressor. RESULTS: The TI group displayed a significant decrease in cortisol post stressor whereas both the MI and comparison groups showed an increase in cortisol. CONCLUSION: The diagnostic threshold of inattentive type ADHD shows HPA axis dysregulation whereas the more mild form does not show dysfunction.