Plasma ghrelin levels and their relationship with gastric emptying in patients with dysmotility-like functional dyspepsia.

BACKGROUND/AIMS: Ghrelin affects gastric motility. However, little is known about the role of ghrelin in the pathophysiology of functional dyspepsia (FD). We investigated plasma ghrelin levels and their relationship with gastric emptying time in dysmotility-like FD patients. METHODS: 42 patients with dysmotility-like FD and 14 healthy volunteers were enrolled in the study. Gastric half-emptying time was measured using a radiolabeled meal. Plasma total ghrelin levels before and after the meal were determined using a radioimmunoassay kit. RESULTS: Preprandial ghrelin levels were significantly lower in FD patients than in controls. Postprandial ghrelin levels were similar between the two groups. Abnormally low preprandial ghrelin levels were observed in 7 out of 42 patients, in whom significant postprandial decrease of ghrelin levels was absent. Delayed gastric emptying was observed in 5 out of 7 patients with abnormally low ghrelin levels. Pre- or postprandial ghrelin levels were not significantly correlated with gastric half-emptying time, both in the patient group and in the control group. CONCLUSIONS: Abnormally low preprandial ghrelin levels and absence of significant postprandial decrease of ghrelin levels are present in a subset of dysmotility-like FD patients. Further investigation on the pathogenetic implication of these alterations in FD is required.

Effects of specific monoclonal antibodies to dense granular proteins on the invasion of Toxoplasma gondii in vitro and in vivo.

Although some reports have been published on the protective effect of antibodies to Toxoplasma gondii surface membrane proteins, few address the inhibitory activity of antibodies to dense granular proteins (GRA proteins). Therefore, we performed a series of experiments to evaluate the inhibitory effects of monoclonal antibodies (mAbs) to GRA proteins (GRA2, 28 kDa; GRA6, 32 kDa) and surface membrane protein (SAG1, 30 kDa) on the invasion of T. gondii tachyzoites. Passive immunization of mice with one of three mAbs following challenge with a lethal dose of tachyzoites significantly increased survival compared with results for mice treated with control ascites. The survival times of mice challenged with tachyzoites pretreated with anti-GRA6 or anti-SAG1 mAb were significantly increased. Mice that received tachyzoites pretreated with both mAb and complement had longer survival times than those that received tachyzoites pretreated with mAb alone. Invasion of tachyzoites into fibroblasts and macrophages was significantly inhibited in the anti-GRA2, anti-GRA6 or anti-SAG1 mAb pretreated group. Pretreatment with mAb and complement inhibited invasion of tachyzoites in both fibroblasts and macrophages. These results suggest that specific antibodies to dense-granule molecules may be useful for controlling infection with T. gondii.

Imported tertian malaria resistant to primaquine.

In Plasmodium vivax and Plasmodium ovale malaria, some of the liver stage parasites remain dormant. The activation of these dormant forms (called hypnozoite) can give rise to relapse weeks, months or years after the initial infection. To prevent relapses, a course of primaquine may be given as terminal prophylaxis to patients. Different strains of Plasmodium vivax vary in their sensitivity to primaquine and, recently, cases of relapse of Plasmodium vivax after this standard primaquine therapy were reported from various countries. We reported a case of primaquine resistant malaria which initially was thought to be relapsed caused by loss of terminal prophylaxis.