Gastro-oesophageal reflux disease: Medical or surgical treatment? Report of an interactive workshop

Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.     

Brain microvascular smooth muscle and endothelial cells produce granulocyte macrophage colony-stimulating factor and support colony formation of granulocyte-macrophage-like cells.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a potent stimulator of macrophages and neutrophils and plays a role in inflammatory diseases. In this article, we report that mouse brain-derived microvascular smooth muscle cells (SM) and endothelial cells (En) in coculture with splenocytes support the colony proliferation of immature granulocyte-macrophage-like (GM) cells. Unstimulated SM and En cells release GM-CSF as shown by ELISA assay and SM expresses mRNA for GM-CSF by polymerase chain reaction (PCR). Stimulation of SM and En by a nonspecific activator (lipopolysaccharide) results in upregulation of GM-CSF production. GM colonies cannot be grown on cultured astrocytes or on extracellular matrix alone prepared from smooth muscle or endothelium. However, colonies form on the extracellular matrix and on astrocytes, either in the presence of SM- or En-conditioned medium or after the addition of recombinant GM-CSF. The GM cells are positive for nonspecific esterase, peroxidase, and MAC-1 markers but are negative for FC gamma receptors and for Thy 1.2, CD8, CD4, MHC class II, and Asialo GM1 markers. These observations emphasize the possibility for active participation of brain microvasculature SM and En in acute inflammatory reactions of the central nervous system.     

Cognitive characteristics of adolescent suicide attempters

The present study examined the relationship among psychiatric diagnosis, depression, attributional style, and hopelessness among 69 adolescent suicide attempters and 40 psychiatrically hospitalized adolescent controls. Contrary to predictions, the suicide attempters were more likely than the nonsuicidal group to attribute good events to global causes. No differences in attributional style were found across the depressed versus nondepressed subjects. However, there was a modest relationship between depression and attributional style. Results suggest that maladaptive cognitive characteristics are present in adolescent clinical samples but may be less specific to suicide attempters than is often suggested.     

Complications in correlation studies between serum, free serum and saliva concentrations of nitrazepam

The relation between free serum and saliva concentrations of nitrazepam in healthy male volunteers has been studied. It was found that the average value of free serum concentrations from all volunteers was twice the average value of corresponding saliva concentrations. Sometimes mean values of serum, free serum and saliva concentrations are used in correlation studies. However, the data from individual volunteers showed that there was no correlation between them. Statistics can easily introduce false pictures for correlations between free serum and saliva concentrations of nitrazepam, whereas no correlation could be found on the basis of results from individuals. In response studies such as the effects of drugs on driving performance, the free serum and saliva concentrations of a drug from individual volunteers should therefore be considered. This will complicate the use of saliva in epidemiological studies on drugs and driving.     

Stimulation or inhibition of the respiratory burst in cultured macrophages in a mycobacterium model: initial stimulation is followed by inhibition after phagocytosis.

Microorganisms cause varying degrees of stimulation of superoxide (O2-) production (respiratory burst [RB]) in macrophages but in some cases apparently inhibit the RB induced in the same monolayers by a conventional stimulator. We have explored these differences. A mycobacterium model, the slowly multiplying mouse pathogen Mycobacterium microti, induced a modest RB in resident macrophage monolayers, compared with the substantial RB induced by opsonized zymosan (Zy). However, if the 1-h M. microti pulse immediately preceded the Zy assay (instead of being concurrent), the RB was consistently less than that elicited by the Zy alone. Cytochalasin (an inhibitor of phagocytosis) enhanced Zy-induced RB, supporting the view that the burst is cell surface mediated, but this agent apparently eliminated the inhibition of the Zy-induced RB caused by prior M. microti exposure, suggesting that this inhibition may have an intracellular origin. The inhibition described extended not only to another mycobacterium (Mycobacterium bovis BCG) but also to a previous application of Zy itself. The general implications for macrophage functions of these observations on timing and sites of initiation are briefly discussed.