Kommentar zu den ESC-Leitlinien ?Guidelines on Diagnosis and Management of Acute Pulmonary Embolism“

As many as 40,000 patients in Germany die of acute pulmonary embolism (PE) each year. The updated (2008) ESC guidelines emphasize the importance of adjusting management strategies to the clinical severity of PE, i.e. the death or complication risk in the acute phase. Haemodynamically unstable patients with suspected high-risk PE should undergo emergency CT pulmonary angiography (CTPA) or, alternatively, echocardiography. If PE is confirmed, thrombolysis or surgical embolectomy should be performed without delay. In normotensive patients (non-high-risk PE), diagnostic algorithms based on multi-detector CTPA are generally preferred. Initial anticoagulation includes low-molecular-weight heparin or fondaparinux. However, selected normotensive patients with right ventricular (RV) dysfunction and/or myocardial injury may benefit from early thrombolysis (intermediate-risk group). Oral anticoagulation for secondary prophylaxis should be continued for at least 3 months. In patients with unprovoked PE, stable INR and low bleeding risk, indefinite anticoagulation may be considered.     

Erythrocyte membrane cholesterol and lipid core growth in a rabbit model of atherosclerosis: Modulatory effects of rosuvastatin

Background

Lipid core expansion is partly responsible for the conversion of a stable atherosclerotic lesion to a rupture-prone plaque. Intraplaque hemorrhage contributes to the accumulation of cholesterol within unstable plaques. In the present study, we investigated, using a rabbit model of atherosclerosis, the extent to which diet-induced increases in cholesterol content of erythrocyte membranes (CEM) contribute to lipid core expansion and the modulatory effect of rosuvastatin use.

Methods and results

Rabbits fed with atherogenic diet (0.75% cholesterol) for 5 months exhibited advanced atherosclerotic lesions (mean plaque area, 0.39 ± 0.03 mm²), and lipid core size was associated with the concentration–time integral (CTI) of CEM levels (r = 0.567, P = 0.004) independent of other established predictors of lipid core size. Further experiments were performed by feeding rabbits atherogenic diet (1% cholesterol) for 3 months, followed by either normal diet or normal diet plus rosuvastatin for the next 3 months. Although no differences were observed in total plaque area between both groups, administration of rosuvastatin was associated with significantly smaller lipid cores, fewer macrophages within the lipid core, less microvessels as well as with lower CTI of CEM levels compared to normal diet alone. Moreover, intraplaque erythrocyte membranes covered a smaller lipid core area in rabbits under rosuvastatin plus normal diet as opposed to rabbits under diet alone.

Conclusions

Increased CEM levels, induced by high-cholesterol diet, are associated with lipid core growth. Ingestion of a potent HMG-CoA reductase inhibitor (rosuvastatin) may decrease CEM levels, and this effect may contribute to regression of the lipid core.     

HIV/AIDS selective infectivity–report of two peculiar cases

We report two peculiar cases that were observed in two communities of Anambra State, South East Nigeria. The first case was a woman of 44 with a history of blood transfusion from a donor of questionable HIV status. A pint of blood was transfused in a private Hospital on the 15 th January, 2000. She has had no form of antiviral therapy until 22nd April, 2008 when she came to the hospital for routine medical check up. Her HIV result came out confirmed positive while that of her husband came out negative. She has had active sexual life with her husband in the previous eight years as they have had some difficulties in getting their desired extra two children having earlier gotten a boy and a girl. The second case involves a family of six. A couple with four children of ages about 6 months, 2 years, 3 years and 5 years. The youngest, a female presented with fever and multiple lymphadenopathy. She tested HIV positive and so was her mother and her second sibling. But her father and two other siblings remained negative at post three and six months intervals from their very first test date with us. These reported cases appear to go contrary to earlier formed opinion on HIV transmission. We support the opinion on a naturally, occurring substance, APOBEC3G which possibly confers permanent immunity against the HIV virus. We recommend clinical trials of the characterized APOBEC3G as a vaccine for non HIV infected persons of all ages and to people living with as a therapeutic drug.     

Comparison of digital systems and conventional dental film for the detection of approximal enamel caries

Objectives

The aims of this study were (1) to compare the accuracy of the detection of approximal enamel caries lesions using three intraoral storage phosphor plate digital systems and one conventional film-based radiographic system; and (2) to determine whether there is a correlation between the histological and radiographic measurements of enamel caries.

Methods

160 approximal surfaces were radiographed under standardized conditions using three storage phosphor stimulable systems (DenOptix and Digora FMX with white and blue plates), and one film system (Insight film). 17 observers scored the images for the presence and depth of caries using a 4-point scale. The presence of caries was validated histologically (gold standard). Two-way analysis of variance was used to test the differences in sensitivity, specificity and overall accuracy (TP + TN). The data from the radiographic and histological measurements were statistically analysed by Spearman’s rank correlation coefficient.

Results

Two-way analysis of variance and the post hoc t-test demonstrated that Digora (white plate) had higher specificity and overall accuracy values than DenOptix (P = 0.021); there was no statistically significant difference among the other imaging modalities (P > 0.05). There was no significant correlation between the histological depth measurements and the radiographic measurements from Digora (blue plate) (P = 0.43), Digora (white plate) (P = 0.15), DenOptix (P = 0.17) and Insight film (P = 0.06).

Conclusions

The results suggest that (1) the performance of the three storage phosphor image plate systems was similar to that of the Insight film for detection of approximal enamel caries, and (2) the increase in histological depth of enamel caries was not significantly correlated with radiographic measurements.     

Differential response of two cell lines sequentially irradiated with low X-ray doses

An experiment was designed to compare the effect of repeated low doses of X-rays in two different cell lines: one transformed, epithelial like and aneuploid Chinese hamster ovary K-1 (CHO-K1); the other originated from a human primary culture, fibroblast, diploid and non-transformed, MRC-5. CHO and MRC-5 cells were cultured for 14 or eight passages, respectively. Irradiation was performed once per passage when cells were in the quiescent state (90?–?95% in G1/G0). Cells were exposed to 10.0 mSv X-ray doses. Ionizing radiation did not induce apoptosis or necrosis in the exposed CHO cell population. Significant increases of low-level damaged cells (degrees 1 and 2) were found for the 14 cycles of radiation when compared with controls, except for the first irradiation cycle. No significant increases in the frequency of cells with severe damage were observed. The frequency of MRC-5 cells with low-level damage increased significantly when compared with controls for radiation cycles seven and eight. Significant increases of apoptosis, necrosis and severe damage were found only for the highest dose. Transformed and non-transformed cell types responded differently to direct and indirect damage using low-dose repeat exposures to ionizing radiation. Though more investigation is needed to understand the mechanisms of radiation effects in chronic low-dose-exposed cell populations, cellular type should be taken into account in the design of in vitro experiments for understanding low-dose-irradiation effects.