Childhood granulomatous periorificial dermatitis in an Asian girl – a variant of sarcoid?

Childhood granulomatous periorificial dermatitis (CGPD) is a benign, facial eruption which has previously been reported in prepubertal, Afro-Caribbean children. It is a condition of unknown aetiology, characterized by a monomorphic, papular eruption around the mouth, nose and eyes. Typically the eruption persists for several months but resolves without scarring. The condition can usually be distinguished from sarcoidosis on clinical and histological grounds. To our knowledge, this is the first case of CGPD occurring in an Asian child with sarcoidal histology and is unusual in its persistence for 4 years. We suggest that this case of CGPD may well be a variant of sarcoid.     

Neuron loss from the hippocampus of Alzheimer's disease exceeds extracellular neurofibrillary tangle formation

Neurofibrillary tangle (NFT) formation in the CA1 region of the hippocampus is one of the early events in the pathogenesis of Alzheimer's disease (AD). As the disease progresses more NFTs form and there is substantial neuron loss. In this study we investigated whether NFT formation accounts for all the CA1 pyramidal neuron loss seen in AD. Using unbiased stereological techniques, we estimated the total number of neurons and the number of intra- and extra-cellular NFTs in the hippocampus of 10 patients with AD and 10 age-matched controls. Marked neuronal loss (approximately 60%) was identified in AD, although NFTs accounted for only a small proportion of this loss (2.2-17.2%, mean 8.1%). Analysis of NFT accumulation with duration of dementia showed a linear relationship, supporting the belief that NFTs progressively accumulate with time.     

Phasic visual alertness in Alzheimer's disease and ageing

An individual's ability to see and react quickly to a target stimulus is enhanced if they are alerted to the arrival of this target by a stimulus that occurs just prior in time to it. This alerting effect is thought to occur due to a phasic increase in alertness mediated by noradrenergic activity. In Alzheimer's disease (AD) there is a dysfunction in the noradrenergic system resulting in a decrease in central levels of noradrenaline. We therefore predicted that patients with AD would not be able to benefit from the prior stimulus to the same extent as that seen in healthy older adults and thus would have a reduced or abolished alerting-effect. We measured reaction times to respond to a visual target that could be preceded (by 200 ms) by a visual alerting cue, in 17 patients with Alzheimer's disease, 19 age-matched controls and 13 younger controls. We found that the alerting cue significantly decreased the reaction times for both the young and old controls, but that this cue had no effect upon the reaction times for those with AD. This marked inability to increase phasic alertness in AD may contribute to the everyday problems faced by these patients, and may provide a simple tool to aid diagnosis and disease progression.     

Evaluation of a nonhomogeneous endometrial echo pattern in the midluteal phase as a potential factor associated with unexplained infertility

OBJECTIVE: To determine whether the failure to develop a homogeneous hyperechogenic pattern in the midluteal phase is associated with decreased fecundity in infertile women who are not receiving follicle-maturing drugs. DESIGN: Observational study. SETTING: Outpatient infertility clinic of a University Medical Center. PATIENT(S): Two hundred ninety-six infertile women (> or =6 months) with regular menses, normal fallopian tubes and uterine cavity, and absence of severe male factor on their initial investigation cycle for follicular dynamic studies. INTERVENTION(S): Midluteal phase sonographic endometrial evaluation. MAIN OUTCOME MEASURE(S): Viable pregnancy rates (live fetus at end of first trimester) according to endometrial echo pattern in the midluteal phase. Other variables considered were age of patient, endometrial thickness and serum E(2) levels at midcycle and midluteal phase, midcycle echo pattern, and P levels in the midluteal phase. RESULT(S): The viable pregnancy rate was significantly higher in those women who exhibited a homogeneous hyperechogenic pattern (8.5%) compared to those women whose endometrium was found to be nonhomogenous (2.2%). No other confounding variables were found that could explain this outcome. CONCLUSION(S): A nonhomogeneous hyperechogenic sonographic endometrial echo pattern predicts lower fertility potential in women who are not receiving follicle-maturing drugs.     

Apoptosis in systemic lupus erythematosus

Systemic lupus erythematosus is a complex, multisystem autoimmune disease characterized by production of high-titer autoantibodies directed against ubiquitously expressed self-antigens. Autoantigens in systemic lupus erythematosus are highly diverse in terms of structure and location in control cells, but become clustered in and on the surface blebs of apoptotic cells. The past several years have provided significant evidence that the apoptotic cell plays a central role in tolerizing B cells and T cells to both tissue-specific and ubiquitously expressed self-antigens, and may drive the autoimmune response in systemic autoimmune disease. The authors review the significant recent advances in this area. Recent studies suggest that predisposing factors to subsequent development of systemic autoimmunity may be the incomplete induction of tolerance to apoptotic antigens, potentially through abnormal apoptotic signaling and effector pathways, decreased apoptotic cell clearance, or abnormal signaling thresholds on responding lymphocytes. In such genetically susceptible hosts, proinflammatory events at the host-environment-immune system interface that lead to the binary change in the response to apoptotic material from tolerance to immunity may be responsible for initiation of autoimmunity and subsequent disease amplification. Such pathways may be amenable to therapeutic and preventive interventions.     

Brief communication: Bone trabeculae are visible on periapical images

It is traditionally believed that the radiographic image of bone striae is a reflection of the trabecular pattern of cancellous bone. Results of a 1999 paper by Cavalcanti et al. contradicted this paradigm, suggesting that the intraoral radiographic image of trabecular pattern in the mandible reflects the morphology of the endosteal surface of the cortical bone, rather than that of cancellous bone. Here, we conduct a simple experiment to assess the contribution of dry mandibular cancellous bone to the image of trabecular pattern seen on intraoral films. Standardized periapical-type radiographs centered on the same region of interest of a dry human mandible were acquired before and after removal of the buccal, then of both cortical plates, together with the endosteal cortical-trabecular bone interface. One oral and maxillofacial radiologist and 4 oral and maxillofacial radiology residents blindly assessed the presence or absence of bone striations on the acquired images. We find that bone striations are visible on periapical-type images of dry human mandibles in the absence of one or both cortical plates, and that their pattern is similar to that seen in the image of the intact specimen. We conclude that cancellous bone contributes significantly to the image of trabecular bone in dry human mandibles.     

A three-field breast treatment technique with precise geometric matching using multileaf collimator-equipped linear accelerators

PURPOSE: Many authors have studied the problems associated with the three-field breast treatment, yet the proposed solutions present their own difficulties. This study presents a technique that overcomes these difficulties, reduces scatter to the contralateral breast, and improves setup reproducibility. METHODS AND MATERIALS: Patients are set up with both arms raised superiorly on a breast board. A precise field-match is achieved by rotating the couch and collimator of the tangents, while the supraclavicular field is half-beam blocked using an independent jaw. The posterior borders of the tangents are conformally defined by multileaf collimation. Measurements were performed to verify the field matching and evaluate scatter doses. RESULT: A smooth dose transition was found at the match line at all depths. Corner blocks and lower wedges were not used, which reduced the scatter to the contralateral breast compared with our prior technique. CONCLUSION: The technique achieves a precise match while removing constraints on the tangents' length and decreasing scatter dose. Procedures for simulation, planning, and treatment have been devised, along with a new patient setup routine incorporating orthogonal setup films and tattoos. This technique has been successfully implemented in routine treatment since September 2001. A program calculating the setup parameters is available at our website.