Once in a lifetime: a case of a pineal tumour

This paper describes the case of a 14-year-old boy who presented to his general practitioner with a history of headaches and visual problems. Investigations subsequently revealed that he had a pineal tumour. The management of the patient is described and this rare condition discussed.     

Molecular characterization of a strain of group a streptococcus isolated from a patient with a psoas abscess

We report the first case of a primary group A streptococcus (GAS) psoas abscess in a 31-year-old woman. The psoas abscess was preceded by an episode of acute pharyngitis. The M-protein gene (emm) and streptolysin S structural gene (sagA) were present in the isolate, with no significant amino acid differences from previously described sequences of M1 GAS isolates. Multilocus sequence typing (MLST) showed that the isolate belonged to MLST sequence type (MLST-ST) 28, the predominant MLST-ST associated with invasive disease caused by M1 isolates.     

Sprinting on a running track: a rare cause of a Lisfranc dislocation

We present a case report of a young man who sustained a serious foot injury while sprinting in a straight line. We discuss the management of these injuries and emphasise the importance of a high index of suspicion amongst orthopaedic, casualty and radiology trainees.     

Preparation of a protein micro-array using a photo-reactive polymer for a cell-adhesion assay

A protein micro-array, called a "cell chip" was constructed by using a photo-reactive polymer for a cell-adhesion assay. Various amounts of albumin or fibronectin were covalently immobilized on a polystyrene dish using a micro-spotter with a dip pen. First, poly(acrylic acid) carrying azidophenyl groups was synthesized as the photo-reactive polymer. Secondly, the aqueous solution of a photo-reactive polymer (several nanoliters) was cast using the dip pen of the micro-spotter and dried in air. Subsequently, aqueous solutions of proteins were cast on the same place using the micro-spotter. After drying, the dish was irradiated with ultraviolet light. Finally, the immobilization was confirmed by staining with a dye. The immobilization was stable even after washing with Tween-20. The protein-immobilized area depended on the manipulation of the micro-spotter and the size of the dip pen. Subsequently, cell adhesion on the photo-immobilized protein micro-array was investigated. The adhesion behavior of cells depended on the kind of immobilized proteins and the kind of cells. The protein micro-array will be useful for cell diagnosis and for the selection of biomaterials to regulate cell behavior.     

Silicone lymphadenopathy mimicking a lymphoma in a patient with a metatarsophalangeal joint prosthesis

With lymph node enlargement, the possibility of a malignant process such as metastatic carcinoma or lymphoma needs to be excluded. This report describes a 47 year old woman with inguinal lymph node enlargement initially suspicious for lymphoma. Fine needle aspiration findings favoured reactive hyperplasia, but a malignant process could not be excluded. The final histological diagnosis was a foreign body granulomatous inflammatory response as a result of regionally disseminated silicone particles from an over looked metatarsophalangeal joint prosthesis. Because of the large number of joint prostheses world wide, it should be kept in mind that migration of wear particles can create granulomatous inflammation and node enlargement.     

The adenosine a2a receptor inhibits matrix-induced inflammation in a novel fashion

Endogenous mediators within the inflammatory milieu play a critical role in directing the scope, duration, and resolution of inflammation. High-molecular-weight extracellular matrix hyaluronan (HA) helps to maintain homeostasis. During inflammation, hyaluronan is broken down into fragments that induce chemokines and cytokines, thereby augmenting the inflammatory response. Tissue-derived adenosine, released during inflammation, inhibits inflammation via the anti-inflammatory A2 adenosine receptor (A2aR). We demonstrate that adenosine modulates HA-induced gene expression via the A2aR. A2aR stimulation inhibits HA fragment-induced pro-fibrotic genes TNF-alpha, keratinocyte chemoattractant (KC), macrophage inflammatory protein (MIP)-2, and MIP-1alpha while simultaneously synergizing with hyaluronan fragments to up-regulate the TH1 cytokine IL-12. Interestingly, A2aR stimulation mediates these affects via the novel cAMP-activated guanine nucleotide exchange factor EPAC. In addition, A2aR-null mice are more susceptible to bleomycin-induced lung injury, consistent with a role for endogenous adenosine in inhibiting the inflammation that may lead to fibrosis. Indeed, the bleomycin treated A2aR-null mice demonstrate increased lung inflammation, HA accumulation, and histologic damage. Overall, our data elucidate the opposing roles of tissue-derived HA fragments and adenosine in regulating noninfectious lung inflammation and support the pursuit of A2aR agonists as a means of pharmacologically inhibiting inflammation that may lead to fibrosis.     

Writing through a robot: a proof of concept for a brain-machine interface

This paper describes a non-invasive human brain-actuated robotic arm experiment, which allows remote writing. In the local environment, the participant decides on an arbitrary word to transmit. A mental speller interface is then used to select the letters. A robot arm placed in the remote environment writes the word on a whiteboard in real time. A multidisciplinary framework such as the one presented here exemplifies a class of interactive applications with possible relevance in a variety of fields, such as entertainment and clinical environments.     

Running a weight control group: experiences of a psychologist and a general practitioner

A weight control group is described, led jointly by a general practitioner and a clinical psychologist. Approaches employed included dietary advice, behavioural advice, and group support. Of the original 16 members (including one group leader), seven dropped out at an early stage and the reasons for this are discussed. All members were re-weighed at intervals up to 18 months after the beginning of the six-month intensive period. They were also interviewed by a psychological research worker a year after the start of the group. The results suggest that a combined dietetic and psychological approach to weight control is of value.     

Investigating a single facet of a multilocus model

We consider looking at a single locus of a multilocus model, such as that for IDDM, in particular the use of the sib-pair method concentrating attention on the influence of HLA.