[Adenocarcinoma of small bowel. An underdiagnosed disease]

BACKGROUND

Small bowel adenocarcinoma is a rare disease. The diagnosis is often disguised by nonspecific and varied presenting symptoms. Adenocarcinoma of the small bowel is typically detected at a late stage and with a poor prognosis.

PATIENTS AND METHODS

The records of 42 patients with small bowel adenocarcinomas diagnosed in 2 surgical clinics between 1995 and 2009 were reviewed for patient and tumor characteristics, treatment effects and survival.

RESULTS

The tumor locations were the duodenum (50%), jejunum (38%) and ileum (12%). In comparison to patients seen before 2004 the observed frequency of emergency operations or palliative procedures as well as stage distribution did not change. The median overall survival was 19 months with a 5-year overall survival of 20%. For patients with resections, reduced performance status, higher stage and residual disease after resection predicted decreased overall survival in univariate analysis. Residual disease and pT category were predictive of survival in multivariate analysis.

CONCLUSION

Complete resection provides the only means of a cure. In cases where curative resection cannot be performed the prognosis remains poor. Further study on the methods for early detection and effective adjuvant chemotherapy should be investigated, however, the available data are limited.

Monosomy and ring chromosome 13 in a thyroid nodular goiter-do we underestimate its relevance in benign thyroid lesions?

Classical cytogenetic examination of a thyroid nodular goiter revealed the existence of two different cytogenetically aberrant cell clones. They were characterized by monosomy 13 as the sole abnormality in one clone, and loss of one chromosome 13 and a ring chromosome that was found to consist of chromosome 13 material by fluorescence in situ hybridization in the other clone. We have concluded that during the course of karyotypic evolution, the instability of the ring chromosome has led to its loss and subsequent monosomy 13. In the literature, two cases of partial monosomy 13 have been reported in adenomatous goiters, suggesting that this abnormality characterizes a rare but distinct subgroup of benign thyroid lesions histologically presenting as adenomatous goiters. Possible target genes of these deletions are the retinoblastoma (RB1) gene locus and the MIR16-1/15A cluster. Based on similar changes in other tumors, it seems reasonable to also analyze a large number of adenomatous goiters for submicroscopic deletions of the long arm of chromosome 13.

On the prevalence of the PAX8-PPARG fusion resulting from the chromosomal translocation t(2;3)(q13;p25) in adenomas of the thyroid

The chromosomal translocation t(2;3)(q13;p25) characterizes a subgroup of tumors originating from the thyroid follicular epithelium and was initially discovered in a few cases of adenomas. Later, a fusion of the genes PAX8 and PPARG resulting from this translocation was frequently observed in follicular carcinomas and considered as a marker of follicular thyroid cancer. According to subsequent studies, however, this rearrangement is not confined to carcinomas but also occurs in adenomas, with considerably varying frequencies. Only five cases of thyroid adenomas with this translocation detected by conventional cytogenetics have been documented. In contrast, studies using reverse-transcription polymerase chain reaction (RT-PCR) detected fusion transcripts resulting from that translocation in an average of 8.2% of adenomas. The aim of this study was to determine the frequency of the PAX8-PPARG fusion in follicular adenomas and to use the HMGA2 mRNA level of such tumors as an indicator of malignancy. In cytogenetic studies of 192 follicular adenomas, the t(2;3)(q13;p25) has been identified in only two cases described herein. Histopathology revealed no evidence of malignancy in either case, and, concordantly, HMGA2 mRNA levels were not elevated. In summary, the fusion is a rare event in follicular adenomas and its prevalence may be overestimated in many RT-PCR-based studies.

The two stem cell microRNA gene clusters C19MC and miR-371-3 are activated by specific chromosomal rearrangements in a subgroup of thyroid adenomas

Thyroid adenomas are common benign human tumors with a high prevalence of about 5% of the adult population even in iodine sufficient areas. Rearrangements of chromosomal band 19q13.4 represent a frequent clonal cytogenetic deviation in these tumors making them the most frequent non-random chromosomal translocations in human epithelial tumors at all. Two microRNA (miRNA) gene clusters i.e. C19MC and miR-371-3 are located in close proximity to the breakpoint region of these chromosomal rearrangements and have been checked for a possible up-regulation due to the genomic alteration. In 4/5 cell lines established from thyroid adenomas with 19q13.4 rearrangements and 5/5 primary adenomas with that type of rearrangement both the C19MC and miR-371-3 cluster were found to be significantly overexpressed compared to controls lacking that particular chromosome abnormality. In the remaining cell line qRT-PCR revealed overexpression of members of the miR-371-3 cluster only which might be due to a deletion accompanying the chromosomal rearrangement in that case. In depth molecular characterization of the breakpoint in a cell line from one adenoma of this type reveals the existence of large Pol-II mRNA fragments as the most likely source of up-regulation of the C19MC cluster. The up-regulation of the clusters is likely to be causally associated with the pathogenesis of the corresponding tumors. Of note, the expression of miRNAs miR-520c and miR-373 is known to characterize stem cells and in terms of molecular oncology has been implicated in invasive growth of epithelial cells in vitro and in vivo thus allowing to delineate a distinct molecular subtype of thyroid adenomas. Besides thyroid adenomas rearrangements of 19q13.4 are frequently found in other human neoplasias as well, suggesting that activation of both clusters might be a more general phenomenon in human neoplasias.

Monitoring compartment-specific substrate cleavage by cathepsins B, K, L, and S at physiological pH and redox conditions

BACKGROUND

Cysteine cathepsins are known to primarily cleave their substrates at reducing and acidic conditions within endo-lysosomes. Nevertheless, they have also been linked to extracellular proteolysis, that is, in oxidizing and neutral environments. Although the impact of reducing or oxidizing conditions on proteolytic activity is a key to understand physiological protease functions, redox conditions have only rarely been considered in routine enzyme activity assays. Therefore we developed an assay to test for proteolytic processing of a natural substrate by cysteine cathepsins which accounts for redox potentials and pH values corresponding to the conditions in the extracellular space in comparison to those within endo-lysosomes of mammalian cells.

RESULTS

The proteolytic potencies of cysteine cathepsins B, K, L and S towards thyroglobulin were analyzed under conditions simulating oxidizing versus reducing environments with neutral to acidic pH values. Thyroglobulin, the precursor molecule of thyroid hormones, was chosen as substrate, because it represents a natural target of cysteine cathepsins. Thyroglobulin processing involves thyroid hormone liberation which, under physiological circumstances, starts in the extracellular follicle lumen before being continued within endo-lysosomes. Our study shows that all cathepsins tested were capable of processing thyroglobulin at neutral and oxidizing conditions, although these are reportedly non-favorable for cysteine proteases. All analyzed cathepsins generated distinct fragments of thyroglobulin at extracellular versus endo-lysosomal conditions as demonstrated by SDS-PAGE followed by immunoblotting or N-terminal sequencing. Moreover, the thyroid hormone thyroxine was liberated by the action of cathepsin S at extracellular conditions, while cathepsins B, K and L worked most efficiently in this respect at endo-lysosomal conditions.

CONCLUSION

The results revealed distinct cleavage patterns at all conditions analyzed, indicating compartment-specific processing of thyroglobulin by cysteine cathepsins. In particular, proteolytic activity of cathepsin S towards the substrate thyroglobulin can now be understood as instrumental for extracellular thyroid hormone liberation. Our study emphasizes that the proteolytic functions of cysteine cathepsins in the thyroid are not restricted to endo-lysosomes but include pivotal roles in extracellular substrate utilization. We conclude that understanding of the interplay and fine adjustment of protease networks in vivo is better approachable by simulating physiological conditions in protease activity assays.

[Symptomatic non-parasitic liver cysts: early and long-term results of surgical management]

BACKGROUND

Symptomatic congenital cysts of the liver, whether solitary or multiple in appearance, can be treated by a laparoscopic approach. Here we present our single centre experience encompassing a rather large cohort of patients.

PATIENTS AND METHODS

From our prospective surgical database, introduced for quality management and surveillance, we identified 34 consecutive patients who were operated on for congenital liver cysts between 1995 and 2004. Using a questionnaire, the patients were contacted to assess actual complaints, the recurrence of operated cysts or the frequency of newly developed cysts. During follow-up two patients had died of other diseases. Of the remaining 32 patients 30 answered the questionnaire (94 %). The median postoperative follow-up was 55 months (range: 8-121).

RESULTS

There were 29 women and 5 men with solitary (n = 10) or multiple (n = 20) liver cysts and polycystic liver disease (n = 4), all complained of unspecific upper abdominal pain. Due to previous operations or coexisting diseases open laparotomy was performed in 7 patients and laparoscopic unroofing was performed in 27 patients. The conversion rate to open laparotomy was 7 % (n = 2). Solitary cysts were unroofed in 25 patients and multiple cysts in 8 patients. The resected cysts had a median diameter of 10.5 cm (solitary cysts: 7-19 cm, multiple cysts: 4-23 cm). The only postoperative complications were 3 cases of bilioma (8.9 %), which required open revision in one case. There were no cysts recurrences, but persisting upper gastrointestinal pain, backache or problems arising from the scars were reported by 9 patients (30 %).

CONCLUSION

In cases of symptomatic congenital liver cysts laparoscopic unroofing should be considered the treatment of choice.

Comet fluorescence in situ hybridization analysis for oxidative stress-induced DNA damage in colon cancer relevant genes

Our objective was to study whether products of oxidative stress, such as hydrogen peroxide (H(2)O(2)), trans-2-hexenal, and 4-hydroxy-2-nonenal (HNE), cause DNA damage in genes, relevant for human colon cancer. For this, total DNA damage was measured in primary human colon cells and colon adenoma cells (LT97) using the single-cell gel electrophoresis assay, known as "Comet Assay." APC, KRAS, and TP53 were marked in the comet images using fluorescence in situ hybridization (Comet FISH). The migration of APC, KRAS, or TP53 signals into the comet tails was quantified and compared to total DNA damage. All three substances were clearly genotoxic for APC, KRAS, and TP53 genes and total DNA in both types of cells. In primary colon cells, TP53 gene was more sensitive toward H(2)O(2), trans-2-hexenal, and HNE than total DNA was. In LT97 cells, the TP53 gene was more sensitive only toward trans-2-hexenal and HNE. APC and KRAS genes were more susceptible than total DNA to both lipid peroxidation products but only in primary colon cells. This suggests genotoxic effects of lipid peroxidation products in APC, KRAS, and TP53 genes. In LT97 cells, TP53 was more susceptible than APC and KRAS toward HNE. Based on the reported gatekeeper properties of TP53, which in colon adenoma is frequently altered to yield carcinoma, this implies that HNE is likely to contribute to cancer progression. This new experimental approach facilitates studies on effects of nutrition-related carcinogens in relevant target genes.

Ferric iron is genotoxic in non-transformed and preneoplastic human colon cells

Iron could be a relevant risk factor for carcinogenesis since it catalyses the formation of reactive oxygen species (ROS), which damage DNA. We previously demonstrated genotoxic effects by ferric iron using the human colon cancer cell line HT29. Here we investigated ferric iron in primary non-transformed colon cells and in a preneoplastic colon adenoma cell line (LT97), which both are suitable models to study effects of carcinogens during early stages of cell transformation. Genetic damage was determined using the Comet assay. Comet FISH (fluorescence in situ hybridization) was used to assess specific effects on TP53. Fe-NTA (0-1000 microM, 30 min, 37 degrees C) significantly induced single strand breaks in primary colon cells (500 microM Fe-NTA: Tail intensity [TI] 22.6%+/-5.0% versus RPMI control: TI 10.6%+/-3.9%, p<0.01) and in LT97 cells (1000 microM Fe-NTA: TI 26.8%+/-7.3% versus RPMI control: TI 11.1%+/-3.7%, p<0.01). With the Comet FISH protocol lower concentrations of Fe-NTA significantly increased DNA damage already at 100 and 250 microM Fe-NTA in primary colon and LT97 adenoma cells, respectively. This damage was detected as an enhanced migration of TP53 signals into the comet tail in both cell types, which indicates a high susceptibility of this tumor relevant gene towards Fe-NTA. In conclusion, Fe-NTA acts genotoxic in non-transformed and in preneoplastic human colon cells, in which it also enhances migration of TP53 at relatively low concentrations. Translated to the in vivo situation these results suggest that iron overload putatively contributes to a genotoxic risk during early stages of colorectal carcinogenesis on account of its genotoxic potential in non-tumorigenic human colon cells.

Influence of antiseptic agents on interleukin-8 release and transmigration of polymorphonuclear neutrophils in a human in vitro model of peritonitis

BACKGROUND

The aim of this study was to evaluate the influence of taurolidine (TAU) and polyhexanid (POLY) on basic inflammatory reactions during peritonitis by using an in vitro model of human peritoneum.

MATERIALS AND METHODS

Human umbilical vein endothelial cells (HUVEC) and human peritoneal mesothelial cells (HPMC; concentration: 2x10(5)/cm2) were brought on a collagen-coated filter insert with 3-microm pore size (HUVEC on the bottom, HPMC on the top), thus resulting in a two-chamber peritoneal model. After 5 days, confluence of the cells was reached, and HPMC were stimulated with 0.5 mL of TNF-alpha (10 microg/mL) for 4 h. Afterwards, 0.5 mL of TAU (1% and 2%) or 0.5 mL of POLY (0.1% and 0.2%) solution were added to the upper (HPMC) compartment. Polymorphonuclear neutrophils (PMN, 10(6)/mL) were placed in the lower compartment 1 h later. After 2 and 6 h, aliquots were taken from the upper compartment and transmigrated PMN were counted. Interleukin-8 (IL-8) concentrations were measured in both compartments by chemiluminescent enzyme immunometric assay. Expression of the adhesion molecules P-selectin and intercellular adhesion molecule-1 (ICAM-1) was assessed by immunohistochemistry. Controls were either TNF-alpha-stimulated HPMC without any antiseptic agents, or stimulated HPMC where TNF-alpha had been substituted by culture medium. Each experiment was performed in triplicate.

RESULTS

Stimulation with TNF-alpha led to a time-dependent increase of IL-8 secretion to the apical compartment resulting in a gradient between both chambers, as well as to a time-dependent increase of PMN transmigration and expression of adhesion molecules. IL-8 gradients and PMN migration were significantly higher as compared to the other groups (p<0.05). After substitution of the stimulus by culture medium, significantly less IL-8 was measured in both compartments. PMN transmigration was almost absent (p<0.05). Addition of POLY and TAU led to comparable low IL-8 gradients with concomitant low PMN transmigration. The initially detected expression of adhesion molecules significantly decreased during the observation time. The IL-8 gradient in all groups correlated significantly with PMN transmigration (r=0.74226; p<0.0001).

CONCLUSION

The diminished IL-8 response together with low PMN transmigration rates after addition of TAU and POLY may reflect either antiinflammatory effects or cellular damage.

Feasibility and accuracy of TRUS in the pre-treatment staging for rectal carcinoma in general practice

AIMS

Transrectal ultrasonography (TRUS) is the diagnostic tool of choice for local staging of rectal carcinoma. The accuracy in determining of tumour infiltration depth has been reported to reach 95% (on average, 85%). The aim of the study was to analyse the diagnostic accuracy of the TRUS in the clinical routine.

PATIENTS AND METHODS

From 01/01/2000 to 12/31/2003, all patients with rectal carcinoma were enrolled in a prospective multicenter observational study. In case of complete findings of pre-operative TRUS and post-operative histological investigation of the surgical specimen on the tumour infiltration depth, overall accuracy of TRUS was determined.

RESULTS

Overall, 13,610 patients with rectal carcinoma were enrolled in the study. Five thousand and fifty-six subjects (37%) underwent TRUS. In 3,501 patients, TRUS finding (uT-stage) could be compared with the result of the definitive histologic investigation (pT-stage). The accuracy of TRUS in all T-stages was 65.8%. The highest sensitivity was achieved in the T3-stage (74.9%), while in T2, T1, and T4, it was 59.6, 59.0 and 31.1%, respectively. In discriminating tumour growth limited to the rectal wall vs that through the rectal wall into the neighboring tissue, TRUS-associated accuracy was 76.5%. There were no differences between various tumour locations above the anocutaneous line.

CONCLUSIONS

Diagnostic accuracy of TRUS in determining depth of tumour infiltration within or through the rectum wall in the routinuous diagnostic of rectal carcinoma does not reach the excellent published study results. A considerable improvement of the qualitative outcome in using this specific diagnostic tool appears to be recommendable to utilize its advantages such as high accuracy, efficacy, and practicability in the diagnostic process and deriving consequences for a possible neoadjuvant treatment as well as optimal planning of the surgical approach.

2-Dodecylcyclobutanone, a radiolytic product of palmitic acid, is genotoxic in primary human colon cells and in cells from preneoplastic lesions

The irradiation of fat results in the formation of 2-alkylcyclobutanones, a new class of food contaminants. Results of previous in vitro studies with primary human colon cells and in vivo experiments with rats fed with 2-alkylcyclobutanones indicated that these radiolytic derivatives may be genotoxic and enhance the progression of colon tumors. The underlying mechanisms of these effects, however, are not clearly understood. Therefore we performed additional investigations to elucidate the genotoxic potential of 2-dodecylcyclobutanone (2dDCB) that is generated from palmitic acid. In particular, we explored the relative sensitivities of human colon cells, representing different stages of tumor development and healthy colon tissues, respectively. HT29clone19A cells, LT97 adenoma cells and primary human epithelial cells were exposed to 2dDCB (150-2097 microM). We determined cytotoxic effects using trypan blue exclusion. Genotoxicity, reflected as strand breaks, was assessed using the alkaline version of the comet assay and chromosomal abnormalities were investigated by 24-color fluorescence-in-situ-hybridization. 2dDCB was cytotoxic in a time- and dose-dependent manner in LT97 adenoma cells and in freshly isolated primary cells but not in the human colon tumor cell line. Associated with this was a marked induction of DNA damage by 2dDCB in LT97 adenoma cells and in freshly isolated colonocytes, whereas in the HT29clone19A cells no strand breaks were detectable. A long-term incubation of LT97 adenoma cells with lower concentrations of 2dDCB revealed cytogenetic effects. In summary, 2dDCB was clearly genotoxic in healthy human colon epithelial cells and in cells representing preneoplastic colon adenoma. These findings provide additional evidence that this compound may be regarded as a possible risk factor for processes in colon carcinogenesis related to initiation and progression.

Effect of inappropriate initial empiric antibiotic therapy on outcome of patients with community-acquired intra-abdominal infections requiring surgery

To assess the significance of initial empiric parenteral antibiotic therapy in patients requiring surgery for community-acquired secondary peritonitis, 425 patients hospitalized between January 1999 and September 2001 in 20 clinics across Germany were followed for a total of 6,521 patient days. Perforated appendix (38%), colon (27%), or gastroduodenum (22%) were the most common sites of infection. Escherichia coli was the most common pathogen. A total of 54 (13%) patients received inappropriate initial parenteral therapy not covering all bacteria isolated, or not covering both aerobes and anaerobes in the absence of culture results. Clinical success, predefined as the infection resolving with initial or step-down therapy after primary surgery, was achieved in 322 patients (75.7%; 95% confidence interval (CI), 70.6-81.2). Patients were more likely to have clinical success if initial antibiotic therapy was appropriate (78.6%; 95% CI, 73.6-83.9) rather than inappropriate (53.4%; 95% CI, 41.1-69.3). Patients having clinical success were estimated to stay 13.9 days in hospital (95% CI, 13.1-14.7), while those who had clinical failure stayed 19.8 days (95% CI, 17.3-22.3). In conclusion, appropriateness of initial parenteral antibiotic therapy was a predictor of clinical success, which in turn was associated with length of stay.

Laparoscopic unroofing of nonparasitic liver cysts within segments VII and VIII: technical considerations

BACKGROUND

The laparoscopic accessibility of congenital liver cysts located in the anterosuperior (VIII) and posterosuperior (VII) segments has been questioned for some time. In support of the laparoscopic approach, we here describe our minimally invasive technique in two patients with solitary congenital cysts located in the apex of liver segments VIII and VII, respectively.

METHOD

Both patients were placed in the inverted Y position. Four trocars were used, their position depending on the location of the cyst.

RESULTS

The segment VIII cyst was easily reached via this anterior approach, while the segment VII cyst required significant mobilization of the right liver lobe. In both cases a complete excision of the cystic roof was achieved using the harmonic scalpel. Without performing an omentoplasty no recurrences were observed after 20 and 28 months, respectively.

CONCLUSION

Solitary cysts located in segments VII and VIII of the liver can be safely treated by laparoscopic unroofing. Cyst recurrences may best be prevented by a complete excision of the cystic roof with an adjacent rim of hepatic parenchyma.

Expression of glutathione S-transferases (GSTs) in human colon cells and inducibility of GSTM2 by butyrate

The glutathione S-transferases (GSTs) are a multigene family of enzymes largely involved in the detoxification of chemicals. In animals, enhanced expression is mediated by products of gut fermentation. Of these, butyrate induces GSTP1 protein expression and GST activity in the human colon tumor cell line HT29. The aim of the following investigations was to further elucidate butyrate-modulated induction of additional colonic GSTs in HT29 and to determine baseline expression in non-transformed cells, isolated from human colorectal tissue. We measured five GST protein subunits (GSTA1/2-composed of GST A1-1, A1-2 and A2-2-GSTM1, GSTM2, GSTP1, GSTT1) by western blot, GST activity using 1-chloro-2,4-dinitrobenzene as substrate and GSTM2 mRNA expression with RT-PCR. GSTP1, followed by GSTT1, were major subunits in all colon cells. Cells isolated from colon tissue were identified to be colonocytes and colon fibroblasts, both of which also expressed substantial levels of GSTM1 and GSTM2. The inter-individual variation of GST subunits in coloncytes of 15 individuals was marked, with total GST protein per 106 cells differing by more than a factor of four. In HT29, butyrate significantly enhanced GSTA1/2 (3.5-fold), GSTM2 (not detectable in controls), GSTP1 (1.5-fold) and GST activity (1.4-fold), but not GSTM1 or GSTT1. GSTM2 mRNA expression was significantly induced after 24 ( approximately 14-fold) and 72 h treatment ( approximately 8-fold). In colon fibroblasts, butyrate (4 mM, 72 h) also induced GSTM2 protein (1.7-fold) and GST activity (1.4-fold). Colonocytes were too short lived to be used for inducibility studies. In conclusion, GSTs are expressed with high inter-individual variability in human colonocytes. This points to large differences in cellular susceptibility to xenobiotics. However, butyrate, an important luminal component produced from fermentation of dietary fibers, is an efficient inducer of GSTs and especially of GSTM2. This indicates that butyrate may act chemoprotectively by increasing detoxification capabilities in the colon mucosa.

Human adenoma cells are highly susceptible to the genotoxic action of 4-hydroxy-2-nonenal

Oxidative stress and resulting lipid peroxidation are important risk factors for dietary-associated colon cancer. To get a better understanding of the underlying molecular mechanisms, we need to characterise the risk potential of the key compounds, which cause DNA damage in cancer-relevant genes and especially in human target cells. Here, we investigated the genotoxic effects of 4-hydroxy-2-nonenal (HNE) and hydrogen peroxide (H(2)O(2)) in human colon cells (LT97). LT97 is a recently established cell line from a differentiated microadenoma and represents cells from frequent preneoplastic lesions of the colon. The genomic characterisation of LT97 was performed with 24-colour FISH. Genotoxicity was determined with single cell microgelelectrophoresis (Comet assay). Comet FISH was used to study the sensitivity of TP53-a crucial target gene for the transition of adenoma to carcinoma-towards HNE. Expression of glutathione S-transferases (GST), which deactivates HNE, was determined as GST activity and GSTP1 protein levels. LT97 cells were compared to primary human colon cells and to a differentiated clone of HT29. Karyotyping revealed that the LT97 cell line had a stable karyotype with only two clones, each containing a translocation t(7;17) and one aberrant chromosome 1. The Comet assay experiments showed that both HNE and H(2)O(2) were clearly genotoxic in the different human colon cells. HNE was more genotoxic in LT97 than in HT29clone19A and primary human colon cells. After HNE incubation, TP53 migrated more efficiently into the comet tail than the global DNA, which suggests a higher susceptibility of the TP53 gene to HNE. GST expression was significantly lower in LT97 than in HT29clone19A cells, which could explain the higher genotoxicity of HNE in the colon adenoma cells. In conclusion, the LT97 is a relevant model for studying genotoxicity of colon cancer risk factors since colon adenoma are common preneoplastic lesions occurring in advanced age.

Putative colon cancer risk factors damage global DNA and TP53 in primary human colon cells isolated from surgical samples

This study describes a novel in vitro method in genetic toxicology that is based on detection of chemical-induced DNA damage connected with altered migration of TP53 in primary human colonocytes. Techniques were developed to isolate high numbers of human epithelial colon cells from surgical tissues. High quantities of viable cells were obtained per donor. The primary cells were treated with the endogenous risk factors trans-2-hexenal, and hydrogen peroxide. Global DNA damage and repair were measured by single-cell gel electrophoresis (Comet assay). We compared responses of primary colon cells to HT29clone19A, a differentiated human colon tumour cell line, for which the karyotype was analysed with 24-colour FISH. Both compounds were genotoxic in both cell types and most of the induced DNA damage was repaired after 30 min. Specific migration of TP53 was determined by fluorescence in situ hybridization (Comet FISH). Using primary colon cells, we quantified the migration of TP53 signals into the comet tails. In these cells TP53 was more sensitive than global DNA for genotoxicity induced by trans-2-hexenal and H(2)O(2). HT29clone19A cells cannot be used for Comet FISH because of their aberrant karyotype. The approach described allows us to obtain more knowledge of putative risk factors in colon carcinogenesis.

Influence of antiseptic agents on interleukin 8 release and transmigration of polymorphonuclear granulocytes in an in vitro model of peritonitis

Background

The effect of antiseptic agents on peritoneal cells is ill defined. The influence of taurolidine (TAU) and polyhexamide (HEX) was investigated in an in vitro model.

Methods

Human umbilical vein endothelial cells (HUVECs) and human peritoneal mesothelial cells (HPMCs) were laid on collagen-coated filter inserts (HUVECs on the bottom, HPMCs on the top), thus representing a two-chamber peritoneal model. When confluence was reached, HPMCs were stimulated with 0·5 ml tumour necrosis factor (TNF) α 10 μg ml−1 for 4 h. Afterwards 0·5 ml TAU (1 and 2 per cent) or 0·5 ml HEX (0·1 and 0·2 per cent) solutions were added to the upper compartment. After 1 h polymorphonuclear granulocytes (PMNs) (105 ml−1) were added to the lower compartment. After 2 and 6 h aliquots were taken from both compartments, transmigrated PMNs were counted and interleukin (IL) 8 concentrations were measured. Controls were either TNF-α-stimulated HPMCs or stimulated HPMCs where culture medium had been substituted for TNF-α. Significance of differences was assessed by analysis of variance with Bonferroni corrections. Correlations were calculated by linear regression analysis.

Results

Stimulation with TNF-α led to a time-dependent increase in PMN transmigration. IL-8 secretion into the apical compartment increased time dependently, resulting in a gradient between the two chambers. After substitution of the stimulus by culture medium, significantly less IL-8 was measured in both compartments. PMN transmigration was almost absent. Addition of HEX resulted in an initial increase in IL-8 levels comparable to TNF controls without further changes. A concentration-dependent decrease in IL-8 gradient was associated with reduced transmigration. The IL-8 gradient between the upper and lower chambers correlated significantly with PMN transmigration (r = 0·8205, P &lt; 0·0001).

Conclusion

The decrease in IL-8 gradients by HEX and the diminished IL-8 response after addition of TAU may reflect either anti-inflammatory effects or cellular damage. Both antiseptic solutions reduced PMN migration, irrespective of continuous stimulation in this model.

Coagulation profiles and intraoperative substitution requirements during elective piggyback liver transplantation with prophylactic antifibrinolytic therapy

During recent years, piggyback liver transplantation (pOLT) with preservation of the retrohepatic vena cava has been introduced in adults. The objective of this study was to evaluate hemostatic changes associated with this transplantation technique. Fifty-seven patients undergoing elective pOLT for endstage liver disease were studied. Most significant changes were observed after graft reperfusion, when PT showed a 49% decrease and activated partial thromboplastin time (aPTT) as well as TT a 2- to 3-fold prolongation. At the same time, factors of the extrinsic coagulation pathway (II, V, VII) revealed an overall 50% decline. Similar changes were observed for antithrombin III (ATIII) and fibrinogen plasma levels. However, only 42% of all patients required intraoperative substitution with coagulation components. There was an association between preoperative fibrinogen (<1.7 g/dl) and ATIII (<50%) plasma levels and the substitution requirement. Multiple linear regression showed a significant correlation between preoperative ATIII activity and intraoperative blood loss. Despite a marked impairment of hemostasis, pOLT can frequently be performed with minimized substitution therapy.

Secondary peritonitis: severity of disease and activation of peritoneal cells

OBJECTIVE

To compare the degree of the inflammatory response of human peritoneum with the severity of peritonitis.

DESIGN

Clinical laboratory study.

SETTING

University hospital, Germany.

SUBJECTS

15 patients with diffuse secondary peritonitis and 5 having conventional cholecystectomy (controls) had peritoneal specimens taken from the site of incision.

MAIN OUTCOME MEASURES

Correlation between presence of indicators of the inflammatory response: interleukin 1 (IL-1), interleukin 6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), antibacterial protein (defensin 3 reflecting the activation of granulocytes), the antibody clone HAM 56 (for detection of local macrophages), and antibodies against macrophage migration inhibiting factor (MIF)-related proteins 8 and 14 (MRP 8 and 14), and clinical state evaluated by the Mannheim Peritonitis Index (MPI), the Peritonitis Index Altona II (PIA II) and the Acute Physiology Score (APS). C-reactive protein (CRP) concentrations were measured preoperatively in the serum.

RESULTS

Expression of MRP 8 and 14, HAM 56, and defensin 3 was significantly higher in patients with peritonitis than in controls (p < 0.05). Expression of IL-1 and IL-6 was almost undetectable. ICAM-1 expression correlated significantly with phagocytic activation. There was no correlation between clinical scores, CRP, and immunohistochemically detectable variables.

CONCLUSION

The pattern of peritoneal inflammatory reactions is relatively uniform and does not correlate with the clinical grading of severity.

[Harmless or life threatening? Properly assessing soft tissue infections]

Soft tissue infections are highly diverse in presentation, and their severity is readily underestimated. Classifications in the literature are not uniform. Clinically, a recommended classification is based on the spread of the infection into deeper regions: superficial and deep soft tissue infections. Superficial infections, that is, those confined to the cutis and subcutis, include furuncles, erysipelas and phlegmons (acute suppurative inflammation). The second group--infection affecting fascia and muscle--include both classical gas gangrene and necrotizing fasciitis which, despite aggressive treatment, are associated with a high mortality rate. The present review shows the classification and differential diagnosis of these infections.

Identification of a differential expression of two cDNAs between malignant mesothelioma and normal mesothelial cells using the RNA fingerprint method

The RNA fingerprint method was used to identify mRNAs that were differentially expressed during the development of human mesothelial cell cancer. We report the isolation of two differentially expressed clones. One clone was expressed in the metastatic mesothelioma cell line M1A and in the malignant mesothelioma cell line M1 and downregulated in normal mesothelial cells. M1 and M1A were derived from a primary and metastatic tumor of the same patient. The other clone was only expressed in normal mesothelial cells. The different expression pattern was confirmed by Northern blot analysis. One clone had a striking sequence homology to the soares pregnant uterus NbHPU homo sapiens cDNA clone. The other clone contained a high sequence homology to the human mRNA for ORF. The biological function of the corresponding genes is unknown. The specificity of expression of the two sequence tags was further examined on different cancer cell lines and normal tissues.

In vitro peritonitis: basic inflammatory reactions in a two-chamber coculture model of human peritoneum

We developed an in vitro model of the peritoneum by coculturing human umbilical vein endothelial cells (HUVEC) and human peritoneal mesothelial cells (HPMC) to gather information on peritoneal physiology and to closer reflect the in vivo situation in humans. HUVEC and HPMC were seeded on collagen-coated polytetraflourethylene-insert membranes of pore size 3 microm. HUVEC were grown on the bottom of the membrane and HMPC on the top. The confluent cells were monitored by measuring transepithelial resistance and by confocal microscopy. The transmigration of PMNs as an important mechanism during secondary peritonitis was studied in this two-chamber model. PMNs were isolated by density separation. After stimulation of HMPC with the complement factor 5 split product C5a (1 ng/ml) or tumor necrosis factor-alpha (TNF-alpha; 10 or 50 microg/ml) for 1 h, 1 x 10(6) PMN were given to the lower compartment. Controls were cocultured cells without stimulation. After 1, 2, and 6 h nonadherent PMNs in the upper compartment were harvested and counted, interleukin-8 was measured in each compartment, and cells on the membrane were paraffin-embedded for immunohistochemistry. Each experiment was performed four times. Cells grew to confluence within 2-5 days and were detected on their respective seeding side by CD34 and cytokeratin 18 counterstaining. Transmigration of PMNs after C5a or TNF-alpha stimulation showed a significant time-dependent increase between 1 h and 6 h (P<0.05). PMNs were found in significantly higher numbers after stimulation with either C5a or TNF-alpha at 1, 2, and 6 h than without stimulation. After stimulation of HPMC, interleukin-8 secretion to the apical compartment increased in a time-dependent fashion, resulting in a gradient between the two chambers. Linear regression analysis revealed significant correlation between transmigrated PMN and interleukin-8 in stimulated cocultures; no correlation was found in controls. This new in vitro peritoneum consisting of cocultured mesothelial and endothelial cells may allow more detailed assessment of peritoneal pathophysiology. Generation of an interleukin-8 gradient affecting the migration of PNMs across the cocultured membrane represents a parameter which may be addressed in further studies.

Local inflammatory peritoneal response to operative trauma: studies on cell activity, cytokine expression, and adhesion molecules

OBJECTIVE

To test the hypothesis that different surgical procedures may lead to different degrees of activation of the human peritoneal response.

DESIGN

Clinical laboratory study.

SETTING

University Hospital, Germany.

MATERIAL

Peritoneal specimens taken from the incision or parietal resection margins at the beginning and end of laparoscopic or open cholecystectomy, or other conventional open operations (n = 5 in each group).

MAIN OUTCOME MEASURES

Detection of indicators of the inflammatory response: interleukin 1 (IL-1), interleukin 6 (IL-6), intercellular adhesion molecule- (ICAM-1), antibacterial protein (defensin 3 that reflects the activation of granulocytes), the antibody clone HAM 56 (for detection of local macrophages), and antibodies against macrophage inhibiting factor (MIF)-related proteins 8 and 14 (MRP 8 and 14).

RESULTS

The rise between preoperative and postoperative evaluations was significant for each variable (p < 0.05). With one single exception (IL-6 between laparoscopic cholecystectomy and other operations), the one way analysis of variance (ANOVA) showed no significant differences among the three groups in the detectable increases in staining. Linear regression analysis showed no correlation between length of operation and increases in immunohistochemically detected inflammatory variables.

CONCLUSION

Minimally invasive surgery does not necessarily mean minimal peritoneal damage. The immunohistochemical evaluation of the local cellular response may provide additional objective criteria for the grading of operative trauma.

Early thoracoscopic debridement and drainage as definite treatment for pleural empyema

OBJECTIVE

To report our experience with early thoracoscopic debridement and drainage in the treatment of pleural empyema in the fibrinopurulent or early organising phase.

DESIGN

Prospective open study.

SETTING

District hospital, Germany.

SUBJECTS

10 Patients operated on between August 1991 and April 1993.

INTERVENTIONS

Double lumen intubation, followed by thoracoscopic opening of the empyema, evacuation of all pus under vision, debridement of the lung, irrigation of the thoracic cavity and insertion of a chest drain.

MAIN OUTCOME MEASURES

Morbidity and mortality.

RESULTS

Cultures taken during the operation grew no pathogens in five cases; Streptococcus pneumoniae, and haemolytic streptococci (once in combination with Staphylococcus aureus), were cultured in two cases each; and Mycobacterium tuberculosis in one. Chest drains were removed a mean of 8.5 days after operation. All patients were well without signs of infection 1-21 months later, and in no case was conversion to open operation necessary.

CONCLUSION

Early thoracoscopic debridement and drainage is a safe and effective alternative to open treatment of patients with pleural empyema in the fibrinopurulent or early organising phase.