[Metaanalysis of EVAR versus open repair for patients undergoing elective repair of abdominal aortic aneurysms]

INTRODUCTION

Elective endovascular abdominal aneurysm repair (EVAR) has become established in the past 20 years as a therapy option for infrarenal abdominal aortic aneurysms (AAA). Even so the benefits of EVAR over open aneurysm repair (OR) are still being discussed controversially.

MATERIALS AND METHODS

A random effects meta-analysis model was used to compare the surgical outcome of EVAR with that of open operations. The end points were evaluated comparatively by use of the Peto odds ratio (Peto OR) and weighted mean differences (WMD). Four prospective randomised studies (EVAR-1, DREAM, OVER, ACE) with a total of 2747 patients (EVAR 1381, OR 1366) were included in the metaanalysis.

RESULTS

In comparison to OR, EVAR was associated with a significantly reduced 30-day mortality rate (Peto OR: 0.373; p<0.001). In addition, there was a statistically significant advantage of EVAR over OR with regard to aneurysm-associated mortality (Peto OR: 0.589, p=0.013) and the length of hospital stay (SD in mean: -0.494; p<0.001). In contrast OR exhibited a lower re-intervention rate than EVAR (Peto OR: 1.843, p<0.001). On consideration of long-term survival (Peto OR: 0,977; p=0.826) and health-related quality of life there were no statistically significant differences between the two therapeutic options (SD in mean: - 0.032, p=0.481).

CONCLUSIONS

In spite of the clinical heterogeneity of the studies included in the metaanalysis, the data indicate that EVAR has a marked benefit with regard to surgical mortality. In the long-term course this advantage in survival is lost but this is not due to the aneurysm-associated mortality.

Lysosomal dysfunction causes neurodegeneration in mucolipidosis II 'knock-in' mice

Mucolipidosis II is a neurometabolic lysosomal trafficking disorder of infancy caused by loss of mannose 6-phosphate targeting signals on lysosomal proteins, leading to lysosomal dysfunction and accumulation of non-degraded material. However, the identity of storage material and mechanisms of neurodegeneration in mucolipidosis II are unknown. We have generated 'knock-in' mice with a common mucolipidosis II patient mutation that show growth retardation, progressive brain atrophy, skeletal abnormalities, elevated lysosomal enzyme activities in serum, lysosomal storage in fibroblasts and brain and premature death, closely mimicking the mucolipidosis II disease in humans. The examination of affected mouse brains at different ages by immunohistochemistry, ultrastructural analysis, immunoblotting and mass spectrometric analyses of glycans and anionic lipids revealed that the expression and proteolytic processing of distinct lysosomal proteins such as α-l-fucosidase, β-hexosaminidase, α-mannosidase or Niemann-Pick C2 protein are more significantly impacted by the loss of mannose 6-phosphate residues than enzymes reaching lysosomes independently of this targeting mechanism. As a consequence, fucosylated N-glycans, GM2 and GM3 gangliosides, cholesterol and bis(monoacylglycero)phosphate accumulate progressively in the brain of mucolipidosis II mice. Prominent astrogliosis and the accumulation of organelles and storage material in focally swollen axons were observed in the cerebellum and were accompanied by a loss of Purkinje cells. Moreover, an increased neuronal level of the microtubule-associated protein 1 light chain 3 and the formation of p62-positive neuronal aggregates indicate an impairment of constitutive autophagy in the mucolipidosis II brain. Our findings demonstrate the essential role of mannose 6-phosphate for selected lysosomal proteins to maintain the capability for degradation of sequestered components in lysosomes and autophagolysosomes and prevent neurodegeneration. These lysosomal proteins might be a potential target for a valid therapeutic approach for mucolipidosis II disease.

[Does Charlson-comorbidity index correlate with short-term outcome in patients with gastric cancer?]

OBJECTIVES

Because of the high prevalence of coexisting medical conditions in patients with gastrointestinal cancer, clinical investigators often need to adjust for comorbidity when assessing the effect of comorbidity on patient outcome. Comorbidity in cancer has been shown to be a major determinant in treatment selection and survival. However, none of the comorbidity studies in patients with gastric cancer reported in the literature have been performed using the Charlson comorbidity index. The purpose of this study was to examine the applicability of the CCI and usefulness of the CCI as a predictor in patients with gastric cancer and to examine whether it correlates with short- term outcome in these patients.

METHOD

Study design was a prospective study. The study population was drawn from our department and included 139 patients who underwent curative treatment of gastric cancer between 1.1.1997 and 31.12.2001. All patients were staged by the CCI for comorbidity and divided into three groups based on the comorbidity severity staging. Group 1 included patients with no comorbidity, group 2 included those with low-level comorbidity and group 3 those with severe comorbidity. Outcomes were compared based on these divisions performing uni- and multivariate analysis.

RESULTS

35 patients (25.2 %) had no, 55 (39.6 %) low and 39 (35.2 %) severe comorbidity. 28.8 % of patients showed no or mild, 14.4 % moderate and 14.4 % of patients severe postoperative complications and 5.8 % died in hospital postoperatively. 30-day-mortality was 3.6 % (n = 5). There was no statistical significant correlation between CCI and occurrence of postoperative complications, severity of postoperative course and postoperative stay in hospital. In multivariate analysis only age was an independent factor for postoperative course.

CONCLUSION

The method of classifying comorbidity by CCI provides a simple, readily applicable and valid method of estimating risk of death from comorbid disease for use in longitudinal studies and in outcomes research from administrative databases. In gastric cancer, however, the CCI was found not to be a valid prognostic indicator.

Complementation cloning identifies CDG-IIc, a new type of congenital disorders of glycosylation, as a GDP-fucose transporter deficiency

Congenital disorders of glycosylation (CDG) comprise a rapidly growing group of inherited disorders in which glycosylation of glycoproteins is defective due to mutations in genes required for the assembly of lipid-linked oligosaccharides, their transfer to nascent glycoproteins (CDG-I) or the processing of protein-bound glycans (CDG-II). Previously' a defect in the GDP-fucose import into the lumen of the Golgi was identified in a person with CDG (A.C.) with a general deficiency of fucosyl residues in glycoproteins. This patient presents the clinical features of leukocyte adhesion deficiency type II (LAD II) including mental retardation, short stature, facial stigmata, and recurrent bacterial peripheral infections with persistently elevated peripheral leukocytes. Using a fucose-specific, lectin-staining procedure for detection of fucosylated glycoproteins and a retroviral cDNA library, we isolated a cDNA complementing the fucosylation defect in the patient's fibroblasts. The cDNA encodes a highly hydrophobic protein of 364 amino acids with multiple putative transmembrane domains. Restoration of GDP-fucose import activity in Golgi-enriched vesicles from the patient's fibroblasts verified the GDP-fucose transporter activity of this protein. We identified two missense mutations in the GDP-fucose transporter cDNA of patient A.C. and of two other people with LAD II. Thus complementation cloning allowed us to identify the human GDP-fucose transporter cDNA and GDP-fucose transporter deficiency as a cause for a new type of CDG. Following the recent recommendations for the nomenclature for CDG, this new type is classified as CDG-IIc (formerly LAD II).

A new type of carbohydrate-deficient glycoprotein syndrome due to a decreased import of GDP-fucose into the golgi

The fucosylation of glycoproteins was found to be deficient in a patient with a clinical phenotype resembling that of leukocyte adhesion deficiency type II (LAD II). While in LAD II hypofucosylation of glycoconjugates is secondary to an impaired synthesis of GDP-fucose due to a deficiency of the GDP-D-mannose-4, 6-dehydratase, synthesis of GDP-fucose was normal in our patient (Körner, C., Linnebank, M., Koch, H., Harms, E., von Figura, K., and Marquardt, T. (1999) J. Leukoc. Biol., in press). Import of GDP-fucose into Golgi-enriched vesicles was composed of a saturable, high affinity and a nonsaturable component. In our patient the saturable high affinity import of GDP-fucose was deficient, while import of UDP-galactose and the activity of GDPase, which generates the nucleoside phosphate required for antiport of GDP-fucose, were normal. Addition of L-fucose to the medium of fibroblasts restored the fucosylation of glycoproteins. We propose that this new form of carbohydrate-deficient glycoprotein syndrome is caused by impaired import of GDP-fucose into the Golgi.