Operative Behandlung von Rektumkarzinomen im Vergleich

BACKGROUND: The laparoscopic resection of rectal cancer shows morbidity and oncological safety comparable to the open approach, but morbidity increases after conversion to open resection. No oncological long-term results are available for the latter patients. METHODS: From 01/01/2000-31/12/2002, patients with curatively resected rectal cancer enrolled in a observational study were evaluated for morbidity, mortality, tumor- and local recurrence rate, paying attention to patients with conversion from laparoscopic to open resection. RESULTS: 237 (3.3%) of 7,189 patients underwent laparoscopic resection (ITT). These patients showed significantly more T1/2 tumors (P<0.001) in earlier UICC stages (P<0.001) than open resected patients. 35 (14.8%) of 237 laparoscopic procedures were converted. Compared with patients receiving complete laparoscopic or open resection, these patients showed significantly higher frequencies of intraoperative (P<0.001) and general postoperative complications (P=0.003) as well as the highest overall morbidity (P=0.031). After a median follow-up of 30.1 months, the highest 5-year local recurrence rate was found in the converted group (16.0%). The laparoscopically resected patients showed a local recurrence rate of 3.3%, patients with open resection of 12.4% (P=0.082). The disease-free survival rate did not differ between the groups (P=0.585). CONCLUSION: Laparoscopic resection of rectal cancer provides oncological results similar to open resection. After conversion, the short and oncological long-term outcomes were worse. Considering a conversion rate of 15%, only a strict indication for the laparoscopic approach can be allowed, and laparoscopic resection should be performed at centers.     

Adequacy of the ELISA test for screening corneal transplant donors

Using a simple mathematical model, we calculated the risk for a patient undergoing penetrating keratoplasty to receive a cornea from a human immunodeficiency virus-infected donor despite negative results on serologic testing of donor serum. This error in serologic testing occurred when false-negative results were obtained from the enzyme-linked immunosorbent assay used to screen donor corneas for human immunodeficiency virus exposure. The average risk of transplanting an infected cornea was low, 0.03%, but increased by a factor of ten when donor tissue from donors at high risk for AIDS was used. Current screening procedures are probably adequate to prevent transmission of human immunodeficiency virus, but increased vigilance for high-risk donor populations may be appropriate.     

CD97, but not its closely related EGF-TM7 family member EMR2, is expressed on gastric,pancreatic, and esophageal carcinomas

CD97 expression is related closely to the dedifferentiation and tumor stage in thyroid carcinomas. We systematically examined the role of CD97 and its closest relative, EMR2, in normal and malignant gastric, esophageal, and pancreatic tissue. The normal tissues were EMR2-, whereas CD97 was expressed slightly in the parietal cells of gastric mucosa and in exocrine pancreatic cells. Interestingly, intralobular and interlobular pancreatic ducts were CD97+. All tumors were EMR2-. CD97 was expressed by 44 of 50 gastric, 14 of 18 pancreatic, and 10 of 13 esophageal carcinomas. Of the 44 gastric cancers, 27 showed disseminated or scattered tumor cells at the invasion front with stronger CD97 expression than tumor cells located in solid tumor formations. There was no correlation between CD97 levels in the tumors or soluble CD97 in the serum samples and the clinicopathologic features of the patients. Taken together, significant numbers of gastric, esophageal, and pancreatic carcinomas are CD97+, whereas its homolog, EMR2, does not have any role in such tumors.     

Structural analysis of alkene/maleic anhydride copolymers

Structural investigations on maleic anhydride (MAn) copolymers with ethene, propene and styrene, their products of hydrolysis, and their methyl half-esters by means of ¹³C NMR spectroscopy are presented. The spectra of 2,3-diethylsuccinic acid and its anhydrides in the erythro- and threo-configuration and of butylsuccinic acid and its anhydride were obtained and compared with the spectra of the copolymers. In each case the results show the formation of both threo(trans)- and erythro(cis)-structures. At a polymerization temperature of 60°C the proportions were 88% threo to 12% erythro for ethene/MAn copolymers and 80% threo to 20% erythro for propene/MAn copolymers, a ratio which was confirmed also by the hydrolyzed forms. Copolymerization at 150°C leads, in the case of propene/MAn, to 67% threo and 33% erythro. The production of ethene/MA copolymer via the copolymerization of ethene and fumaric acid half-ester and its saponification to ethene/fumaric acid leads to a ratio of 38% threo to 62% erythro. These results are in accordance with the thermal stabilities of the configurations. In the case of styrene/MAn copolymer it is not possible to obtain a unique interpretation of the configurations from the spectra. For the conversion of propene/MAn and styrene/MAn copolymers by means of methanol to half-esters it can be derived from the ¹³C NMR spectra how many of the half-ester moieties are obtained in the neighbourhood of the methyl and phenyl groups, respectively, of the olefin.     

Association of ambient air‐pollution levels with acute asthma exacerbation among children in Singapore

BACKGROUND: Air-pollution levels have been shown to be associated with increased morbidity of respiratory diseases. METHODS: Data for ambient air-pollutant levels, meteorologic factors, and hospitalization or emergency room (ER) visits for acute asthma in Singapore children over a 5-year period (1990-4) were obtained and analyzed for associations by time-series methods. RESULTS: Throughout this period, the annual mean and 24-h mean levels for sulfur dioxide (SO2), nitrogen dioxide (NO2), and total suspended particles (TSP) and maximum 1-h daily average for ozone were generally within the air-quality guidelines established by the World Health Organization (WHO). However, positive correlation between levels of each of these pollutants and daily ER visits for asthma was observed in children aged 3-12 years, but not among adolescents and young adults (13-21 years old). The association with SO2 and TSP persisted after standardization for meteorologic and temporal variables. An adjusted increase in 2.9 ER visits for every 20 microg/m3 increase in atmospheric SO2 levels, lagged by 1 day, was observed on days when levels were above 68 microg/m3. With TSP, an adjusted increase of 5.80 ER visits for every 20 microg/m3 increase in its daily atmospheric levels, lagged by 1 day, was observed on days with levels above 73 microg/m3. Similar results were also obtained after controlling for autocorrelation by time-series analysis. CONCLUSIONS: These associations were observed even though the overall levels of all pollutants were generally within the air-quality guidelines established by the WHO. These findings suggest that asthmatic children are susceptible to increased levels of air pollutants, particularly SO2 and TSP, although the ambient levels are generally within "acceptable" ranges.     

Graves' disease is associated with an altered CXCR3 and CCR5 expression in thyroid-derived compared to peripheral blood lymphocytes

The mechanisms by which T cells accumulate in the thyroid and support the autoimmune process in patients with Graves' disease (GD) are poorly understood. Chemokines and their receptors may be involved in this process. We have analysed the expression of CXCR3 and CCR5 as Th1-specific chemokine receptors, CCR3 as a marker for Th2 cells, CXCR4 (expressed on unprimed, naive T cells) and CCR2 (known to be involved in autoimmunity) on peripheral blood (PBL) and thyroid-derived lymphocytes (TL) using flow cytometry. Chemokine receptor expression on PBL of GD patients (n = 16) did not differ from that of normal controls (n = 10). In GD, CXCR3+ (67.3 +/- 4.0% versus 45.7 +/- 2.1%) and CCR5+ T cells (42.5 +/- 3.4% versus 18.8 +/- 2.1%) showed a significant enrichment in the TL compared to PBL. The positive cells were contributed mainly by the CD4+CD45R0+ subset. TL are mostly primed CD45R0+ T cells, but surprisingly, they had significantly higher levels of CXCR4+ cells among TL (96.2 +/- 1.0%) compared to PBL (66.8 +/- 4.2%). However, CXCR4 has been induced during in vitro isolation of TL. There was no correlation between chemokine receptors and the level of TSH-receptor and thyroid peroxidase autoantibodies. CCR3+ and CCR2+ cells remained unchanged in TL compared to PBL. We could confirm the results using RT PCR and immunohistology. In summary, TL showed a different chemokine receptor pattern compared to PBL from the same patient. This indicates a role for CXCR3 and CCR5 in the recruitment of T cells to the thyroid in GD.