Holotranscobalamin Levels in Children with Helicobacter pylori Infection.

BACKGROUND: The purpose of this study was to evaluate the association between vitamin B12 levels and Helicobacter Pylori infection and to examine the clinical usefulness of holotranscobalamin (holoTC) measurement in children. MATERIALS AND METHODS: Thirty patients between 6 and 15 years of age, who were diagnosed as H. pylori infected by C(14) urea breath test, and 26 controls were enrolled in the study. Tests for complete blood count, serum vitamin B12 and folate, plasma total homocysteine, and holoTC levels were performed in each patient in the study and control groups. RESULTS: Mean plasma holoTC concentrations were significantly lower in children with H. pylori infection before treatment (median 23.7 pmol/L (12.9-37.1 pmol/L)) versus after treatment (median 38.2 pmol/L (21.2-61.4 pmol/L)) and controls (median 36.1 pmol/L (12.6-58.7 pmol/L)). CONCLUSIONS: The findings of our study suggest that H. pylori infection has a reversible negative effect on vitamin B12 status reflected in a decreased level of plasma holoTC that normalizes upon treatment of the infection, while no change is observed in total plasma vitamin B12 .

The effect of about one third craniectomy on the cerebrospinal fluid flow rate as estimated by radionuclide cisternography in normal rabbits.

Since, the effect of a large cranial defect on the cerebrospinal fluid (CSF) flow rate is still not clear, this study was designed to evaluate the effect of craniectomy in rabbits by using a radionuclide technique, under in vivo physiologic conditions. Eleven male New Zealand white rabbits were examined. After the injection of technetium-99m-diethylene-triaminepenta-acetic acid into the fourth ventricle of each rabbit, dynamic acquisition for 60 min (1 min per frame) was performed pre-op followed by about one third craniectomy to each animal. Injection of the radiopharmaceutical and the imaging steps were repeated at 24 h (post-op 24 h) and at 7 days (post-op 7 d) after craniectomy. The region of interest (ROI) was drawn around the injection site and a time activity curve was generated. Slopes of each curve were calculated to detect the flow rate of the radiopharmaceutical from the injection site during 60 min. Besides, the count decreased ratio (ROIcounts of the last frame ROI counts of the first frame X100) was calculated. Our results showed that the pre-op values of the slope of the time-activity curve and the count decreased ratio were decreased 24 h and 7 d post-op but statistically significant was only the difference between the above values pre-op and 7 d post-op (P=0.04, P=0.01 respectively). In conclusion, the data of the present study indicate that the CSF flow rate in rabbits decreased 7 d after one third craniectomy.

A physiologic approach to decreasing upward creep of the heart during myocardial perfusion imaging.

UNLABELLED: When body position changes from erect to supine, the effect of gravity on the organs also changes and is a possible underlying mechanism for upward creep of the heart during SPECT acquisitions. We hypothesized that if we provide enough time for the organs to settle after a positional change, the range of this vertical motion causing reconstruction artifacts can be decreased. Our aim was to evaluate the effect that a 5-min bed rest on the imaging table before both rest and stress SPECT acquisitions would have on upward creep of the heart. METHODS: Before both stress and rest SPECT acquisitions, the first 101 consecutive patients (group A) had a 5-min bed rest and the remaining 99 patients (group B) did not have any bed rest after they were positioned on the imaging table. Upward creep was detected by comparing the distance between the lower edge of the image and the lowest part of the heart silhouette on the last projection image of detector 2 and the first projection image of detector 1. RESULTS: Upward creep was found in 53% (54/101) and 55% (56/101) of patients in group A and in 89% (88/99) and 86% (85/99) of patients in group B in stress and rest SPECT studies, respectively. Upward creep of the heart was decreased prominently in group A, and this decrease was statistically significant (p < 0.001). CONCLUSION: We conclude that before SPECT acquisition, at least a 5-min bed rest on the imaging table significantly decreases vertical motion of the heart.

Altered biodistribution of FDG in patients with type-2 diabetes mellitus.

OBJECTIVE: Positron emission tomography-computed tomography (PET-CT) imaging of patients with diabetes can be problematic because elevated glucose levels may cause competitive inhibition of [F-18]-2-deoxy-2-fluoro-D-glucose (FDG) uptake in different tissues. Therefore, the aim of the study was to evaluate the biodistribution of FDG in patients with type-2 diabetes mellitus. METHODS: Two hundred forty patients were retrospectively enrolled to the study. Study population was divided into three subgroups, named as the normal (group 1), the insulin (group 2) and the oral anti-diabetic (group 3). Unenhanced low-dose CT and PET emission data were acquired from the mid-thigh to the vertex of the skull. FDG uptakes in different organs were evaluated qualitatively or semi-quantitatively. RESULTS: In the diabetic groups, diffuse FDG uptake of the colon was increased (p > 0.001) but segmental FDG uptake was decreased (p > 0.001). Intestinal FDG uptake was detected in 20 % of the study population and only 3 % of these uptakes were in diffuse pattern. Segmental FDG uptake in the bowel was increased significantly in the groups of patients with diabetes (p = 0.002). Maximum standardized uptake values of the liver in the groups 1, 2, and 3 were 2.66 ± 0.6, 3.25 ± 0.9 and 3.16 ± 0.8, respectively, and the difference between the groups was not statistically significant (p = 0.083). Cardiac FDG uptake was decreased significantly in the groups of patients with diabetes (p < 0.001). CONCLUSIONS: According to our results, whole body biodistribution of FDG uptake seems to be changed in patients with type-2 diabetes who were using insulin or oral antidiabetic drugs. Although the use of oral antidiabetic drugs was known to change the biodistribution of FDG, insulin use also seems to change FDG uptake in different organs of diabetic patients.

Scintigraphic imaging of endothelium-dependent vasodilation in the forearm: a preliminary report.

BACKGROUND: The diagnosis of endothelial dysfunction has been gaining clinical importance, but although endothelial function testing is available in the research setting, no technique yet exists that is simple, safe, reproducible and easily performed as a clinical screening method. The aim of this study was to design a new, scintigraphic method of imaging the flow-mediated dilation in the forearm, which represents the functional characteristic of endothelial dysfunction. METHODS AND RESULTS: The study group comprised 118 subjects in whom left forearm ischemia was induced by inflating a sphygmomanometer cuff to supra systolic pressure for 4.5 min. Later, dynamic acquisition (2 s frame/min) was initiated after the injection of technetium-99m methoxy-isobutyl isonitril into the dorsal pedal veins. Equivalent regions of interest were drawn on both arms to detect total activity counts during 1 min and the perfusion ratios (left arm/right arm) were calculated. The left arm counts (22,203.3+/-12,372.7) were significantly higher than the right arm counts (9,980.9+/-5,931.9) (p<0.001). A significant decrease in perfusion ratios was noted in the hypertension and hypercholesterolemia groups. An increase in the number of risk factors caused an insignificant decrease in perfusion ratio (p=0.346). CONCLUSION: Non-invasive evaluation of endothelium-dependent vasodilation by semiquantitative scintigraphic method using radioactive perfusion tracer provided promising results.