The causes of musculoskeletal chest pain in patients admitted to hospital with suspected myocardial infarction

BACKGROUND: We wished to investigate the causes and characteristics of musculoskeletal chest pain leading to acute medical admission. METHODS: We studied patients admitted to Queen Elizabeth Hospital, Gateshead, over a 10-week period. Patients with chest pain for which no acute cardiorespiratory cause was evident were identified and only included if they were tender on anteroposterior chest compression, thoracic spine rotation or firm sternal pressure. A detailed clinical history, anxiety and depression scale and a focussed physical examination were done to define the nature of musculoskeletal disease and their therapeutic requirements. RESULTS: Fifty patients satisfying the inclusion criteria were admitted in the 10-week period and comprised 54% females with a mean age of 57 years (S.D.=13.48). Chest pain lasted for 1 h or less in 24 patients and was mostly anterior. Three distinct groups of patients were identified. Twelve patients had evidence of inflammatory joint disease, thirteen had fibromyalgia and half had regional syndromes with pain arising from the shoulder, neck, thoracic spine or sternocostal areas. Visual analogue scores were highest in fibromyalgia for pain, and highest in inflammatory arthritis for impaired mobility. Anxiety and depression scores were highest in fibromyalgia and lowest among patients with regional syndromes. CONCLUSIONS: Musculoskeletal causes for acute chest pain are common and varied. Most patients have an identifiable cause of pain, but accurate diagnosis is needed to select the most appropriate intervention. Anxiety and depression are frequent, with much self-reported pain and dysfunction. However, all patients in this study had a disorder that was amenable to treatment and diagnosis. Management needs to be actively pursued in all patients.     

Microbial contamination of enteral feeding solutions in a community hospital

Seven related studies were done to estimate the type and amount of contamination that occurred in nutrient feeding solution when administered according to procedure in a community hospital. The initial study was done in a simulated nonclinical setting with select technicians monitoring for gavage systems delivering a commercially prepared nutrient feeding solution. The solution remained sterile over 48 hr. In the second study, various nurses maintained the enteral feeding simulations unaware of the objective of study. Significant contamination was found, but a decrease occurred when the study was duplicated and the nurses were made aware that contamination was the issue being studied. The subsequent study had all gavage equipment in clinical use in the hospital on a given day cultured for microbial contamination. Significant contamination was present and did not decrease when the study was duplicated following inservice training. Suggestions for standards of care are made.     

Variants of uncertainty in decision-making and their neural correlates

When leaving the tidy world of rules and people start judging probabilities on an intuitive basis, it revealed that they have some intuitions to choose from. One could refer to them as a family of subjective probability concepts or following Kahneman and Tversky, as variants of uncertainty. The authors distinguished between external and internal attributions of uncertainty and could show that the perceived reason of uncertainty determines the selected coping strategy. To investigate whether variants of uncertainty can also be distinguished on the cerebral level, two functional magnetic resonance imaging studies were conducted. Participants had to predict events (abstract visual stimuli) under parametrically varying degrees of (un-)certainty. In the first experiment, uncertainty was induced by the manipulation of event probability (externally attributed uncertainty). In the second experiment, uncertainty depended on participants' knowledge of valid rules of event occurrence, as trained before the experimental session (internally attributed uncertainty). As a result, parametric analyses revealed that activation within the posterior fronto-median cortex, particularly within mesial Brodmann area (BA) 8, increased with increasing uncertainty, no matter for which reason uncertainty emerged. Furthermore, it was found that different variants of uncertainty entailing different coping strategies can be dissociated due to additionally activated networks. Concluding, increasing activation within mesial BA 8 reflects that we are uncertain, additional networks what we do to resolve uncertainty in order to achieve future rewards. Hence, the phenomenological distinction between processes related to externally and internally attributed uncertainty is paralleled on the cerebral level.     

Methylphenidate analogs with behavioral differences interact differently with arginine residues on the dopamine transporter in rat striatum

The methylphenidate analogs N-methyl-4-methyl-methylphenidate and N-benzylmethylphenidate are believed to interact differently with the dopamine transporter (DAT) in vitro and in vivo. Herein, we report that methylphenidate and N-methyl-4-methyl-methylphenidate, but not N-benzylmethylphenidate, protect the rat striatal DAT from the arginine-selective chemical modifying agent, phenylglyoxal. This suggests that methylphenidate and N-methyl-4-methyl-methylphenidate, but not N-benzylmethylphenidate, interact with the guanidine groups of arginine residues in the DAT of rat striatum. This differential interaction may, at least in part, explain the in vitro and in vivo differences between N-methyl-4-methyl-methylphenidate and N-benzylmethylphenidate.     

Determination of the peptide binding motif and high-affinity ligands for HLA-DQ4 using synthetic peptide libraries

Juvenile idiopathic arthritis (JIA) is considered to be an autoimmune disease. Various human leukocyte antigen (HLA) associations for different subgroups of this heterogeneous disease have been found. For early-onset pauciarticular arthritis (now oligoarthritic JIA), a strong association with the HLA class II haplotype DQA1*0401/DQB1*0402 (DQ4) has been described. We determined the peptide-binding specificities of this HLA-DQ molecule by screening a synthetic acetylated nonapeptide amide library with one defined and eight random sequence positions. A characteristic binding motif could be deduced. By use of these data, we designed defined specific nonapeptides and identified high-affinity ligands binding to HLA-DQ4. The peptide binding motif of HLA-DQ4 is very similar to the motif of HLA-DQ7, also associated with oligoarthritic JIA. It is, however, different from binding motifs of neutral or protective HLA-DQ molecules. Our results further support the idea of differential peptide presentation in the pathogenesis of oligoarthritic JIA.     

Children grow and horses race: is the adiposity rebound a critical period for later obesity?

Background  

The adiposity rebound is the second rise in body mass index that occurs between 3 and 7 years. An early age at adiposity rebound is known to be a risk factor for later obesity. The aim here is to clarify the connection between the age at rebound and the corresponding pattern of body mass index change, in centile terms, so as to better understand its ability to predict later fatness.     

An enzyme-linked immunosorbent assay for lipovitellin quantification in copepods: a screening tool for endocrine toxicity

Vitellogenin (VTG) has been widely used as a biomarker of estrogenic exposure in fish, leading to the development of standardized assays for VTG quantification. However, standardized quantitative assays for invertebrate, particularly crustacean, lipovitellin (also known as vitellin [VTN]) are lacking. In this study, a fluorescence-based VTN enzyme-linked immunosorbent assay (ELISA) was developed to quantify microquantities of VTN in the estuarine, sediment-dwelling copepod Amphiascus tenuiremis. This ELISA utilizes a VTN-specific polyclonal antibody developed against amphipod (Leptocheirus plumulosus) embryo VTN and exhibits specificity toward female copepod proteins. In routine assays, the working range of the ELISA was 31.25 to 1,000 ng/ml (75-25% specific binding/maximum antibody binding [B/B0]) with a 50% B/B0 intra- and interassay variation of 3.9% (n = 9) and 12.5% (n = 26), respectively. This ELISA is capable of detecting VTN as low as 2 ng/ml, and can accurately detect VTN in as few as four copepods. The ELISA significantly discriminated positive (gravid female) and negative (male) samples, and was suitable for screening endocrine toxicity in copepods. Stage-I juvenile copepods were individually reared to adults in aqueous microvolumes of the phenylpyrazole insecticide, fipronil, and whole-body homogenate extracts were assayed for VTN levels. Fipronil-exposed virgin adult females, but not males, exhibited significantly higher levels of VTN relative to control males and females. This crustacean VTN ELISA is likely useful for evaluating endocrine activity of environmental toxicants in copepods and other crustacean species.