Situation models in language comprehension and memory

This article reviews research on the use of situation models in language comprehension and memory retrieval over the past 15 years. Situation models are integrated mental representations of a described state of affairs. Significant progress has been made in the scientific understanding of how situation models are involved in language comprehension and memory retrieval. Much of this research focuses on establishing the existence of situation models, often by using tasks that assess one dimension of a situation model. However, the authors argue that the time has now come for researchers to begin to take the multidimensionality of situation models seriously. The authors offer a theoretical framework and some methodological observations that may help researchers to tackle this issue.     

Principles of urodynamics pressure measurement and its implication to female continence function

Urodynamic pressure measurements using catheters have been widely used among clinicians. More often objective interpretation of urodynamic pressure measurements requires fundamental understanding of pressure measurement techniques due to many measurement artifacts. In this study we developed a simplified compound thick-walled cylinder model to investigate the mechanical nature of urodynamic pressure measurement as well as pressure transmission. Efficacy of collagen implantation was also explored. Lamé's formulation was used to find analytical solutions. Pressure transmission can be related to catheter caliber and the compressibility of the urethral tissue (poisson ratio) in a simple mathematical form. The theoretical pressure transmission ratio will be 133% with the additional incompressibility assumption, reflecting the passive structural transmission of intraabdominal pressure increase. The relationship between the pressure measurement error and the catheter caliber was found to be linear (r2 = 0.94 +/- 0.04) and two or more pressure measurements need to be used to find the uninstrumented pressure. It was predicted that collagen implantation treatment might improve the pressure transmission ratio maximally by 33%.     

Breast abscess: coagulase-negative staphylococcus as a sole pathogen

Breast abscesses in nonlactating women are very uncommon. Rarely have cases been reported in which coagulase-negative staphylococci have been isolated in pure culture. We describe a 67-year-old patient who had such an abscess. Specimens obtained by fine needle aspiration, incision and drainage, and biopsy of the breast mass all showed acute inflammation and many gram-positive cocci on gram stain and histologic examination; cultures of all specimens yielded many coagulase-negative staphylococci. The patient responded well to incision and drainage and therapy with antibiotics.     

Uroporphyria induced by 5-aminolaevulinic acid alone in Ahrd SWR mice

In mice, depression of hepatic uroporphyrinogen decarboxylase (UROD) leading to porphyrin accumulation (uroporphyria) occurs with chlorinated ligands of the aryl hydrocarbon (AH) receptor especially after iron overload. However, in the absence of chlorinated ligands, iron itself will eventually cause uroporphyria, but this response is not associated with the Ahr genotype. These effects are potentiated by administration of the haem precursor 5-aminolaevulinate (ALA). The aim of this study was to investigate the effects of ALA alone. Prolonged administration of 2 mg ALA/mL in the drinking water to SWR mice also led to decarboxylase insufficiency (11% of control) and uroporphyria by 8 weeks, whereas DBA/2 mice did not show reduced enzyme activity. Both strains are considered AH nonresponsive and analysis of the Ahr gene using restriction fragment length polymorphism was consistent with SWR, like DBA/2, possessing the Ahrd allele. Exposure of isolated hepatocytes to ALA (150-500 microM) for up to 48 hr showed a significant accumulation of both uroporphyrin and coproporphyrin in the medium, which for uroporphyrin particularly was significantly greater with SWR than with DBA/2 cells. Basal in vivo CYP1A2 activity, measured as microsomal methoxyresorufin dealkylation, was significantly greater in SWR than in DBA/2 mice (1.3-fold), but it was unclear whether this was sufficient to explain the marked difference in sensitivities of the two strains. Despite SWR mice being AH nonresponsive, uroporphyria and decarboxylase depression after an initial iron overload and ALA for 3 weeks were greatly potentiated by a single dose (100 mg/kg) of hexachlorobenzene (a weak AH ligand). The results demonstrate that there is a genetic difference in mice independent of the Ahr genotype and response to iron, which influences the susceptibility to ALA-induced uroporphyria. Thus chemicals, iron and ALA can act independently, but also together, to cause porphyria in susceptible individuals.     

Comparison of 55% TFA/CH2Cl2 and 100% TFA for Boc group removal during solid-phase peptide synthesis

Much has been written about closure of large spina bifida defects. There is an increased demand to close these defects irrespective of the final outcome of the patient. Plastic surgeons may become involved in the closure of large defects. Perforator vessels of the back passing through the latissimus fascia can maintain viability of triangular island flaps. Therefore, such flaps can be used to close the large midline defects of spina bifida. This article reviews the literature and presents a simple technique based on anatomical properties of the region surrounding the defect.     

Memory for pain and affect in chronic pain patients

Radioligand binding studies were performed to determine the effect of various cations on the characteristics of [3H]glibenclamide binding to its high-affinity receptor in rat cerebral cortex membranes. Mg2+ was shown specifically to reduce radioligand binding to membranes pretreated with 5 mM EDTA. CaCl2 enhanced [3H]glibenclamide binding whilst MnCl2, KCl and NaCl were without significant effect. 2 mM MgCl2 induced a statistically significant rightward shift in the dissociation constant for glibenclamide obtained from both saturation and competition studies. These results suggest that Mg2+ may participate in the regulation of the sulphonylurea receptor in the rat cerebral cortex.     

Audit and its impact in the management of early prostatic cancer

An analysis was made of a prospective database of 614 men with newly diagnosed carcinoma of the prostate who presented between January 1978 and December 1990; 3-monthly updates were available on their clinical, haematological and biochemical parameters and 6-monthly updates on chest X-rays, bone scans and skeletal X-rays. It was found that 107 men (mean age 73.5 years) had early disease at presentation. Their management was based on regular surveillance and the treatment deferred until disease progression or development of symptoms. The audit of outcome measured various clinical events. Four patients (3.7%) developed local failure, 11 (10.3%) developed bone metastases, 3 (2.8%) died of cancer with a median survival of 6.3 years, and 34 (31.8%) died of intercurrent disease with a median survival of 2.6 years. The observed survival for 12 years of the whole group was similar to the expected survival for an age-matched population in Scotland. The standardised mortality ratio was 81 (95% confidence limits 57-112).