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Background  In the German hospital reimbursement system (G-DRG) endoscopic procedures are listed in cost center 8. For reimbursement between hospital departments and external providers outdated or incomplete catalogues (e. g. DKG-NT, GOÄ) have remained in use. We have assessed the cost for endoscopic procedures in the G-DRG-system. Methods  To assess the cost of endoscopic procedures 74 hospitals, annual providers of cost-data to the Institute for the Hospital Remuneration System (InEK) made their data (2011 - 2015; § 21 KHEntgG) available to the German-Society-of-Gastroenterology (DGVS) in anonymized form (4873 809 case-data-sets). Using cases with exactly one endoscopic procedure (n = 274 186) average costs over 5 years were calculated for 46 endoscopic procedure-tiers. Results  Robust mean endoscopy costs ranged from 230.56 € for gastroscopy (144 666 cases), 276.23 € (n = 32 294) for a simple colonoscopy, to 844.07 € (n = 10 150) for ERCP with papillotomy and plastic stent insertion and 1602.37 € (n = 967) for ERCP with a self-expanding metal stent. Higher costs, specifically for complex procedures, were identified for University Hospitals. Discussion  For the first time this catalogue for endoscopic procedure-tiers, based on § 21 KHEntgG data-sets from 74 InEK-calculating hospitals, permits a realistic assessment of endoscopy costs in German hospitals. The higher costs in university hospitals are likely due to referral bias for complex cases and emergency interventions. For 46 endoscopic procedure-tiers an objective cost-allocation within the G-DRG system is now possible. By international comparison the costs of endoscopic procedures in Germany are low, due to either greater efficiency, lower personnel allocation or incomplete documentation of the real expenses., Competing Interests: Interessenkonflikt: M. Rathmayer, W. Heinlein, C. Reiß, M. Wilke haben als Berater bei der Durchführung der Kostenstudie und deren Auswertung ein Beratungshonorar von der Deutschen Gesellschaft für Gastroenterologie, Verdauungs- und Stoffwechselerkrankungen e. V. erhalten., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: The German hospital reimbursement system (G-DRG) is incomplete for endoscopic interventions and fails to differentiate between complex and simple procedures. This is caused by outdated methods of personnel-cost allocation., Methods: To establish an up-to-date service catalogue 50 hospitals made their anonymized expense-budget data available to the German-Society-of-Gastroenterology (DGVS). 2.499.900 patient-datasets (2011-2013) were used to classify operation-and-procedure codes (OPS) into procedure-tiers (e.g. colonoscopy with biopsy/colonoscopy with stent-insertion). An expert panel ranked these tiers according to complexity and assigned estimates of physician time. From June to November 2014 exact time tracking data for a total 38.288 individual procedures were collected in 119 hospitals to validate this service catalogue., Results: In this three-step process a catalogue of 97 procedure-tiers was established that covers 99% of endoscopic interventions performed in German hospitals and assigned validated mean personnel-costs using gastroscopy as standard. Previously, diagnostic colonoscopy had a relative personnel-cost value of 1.13 (compared to gastroscopy 1.0) and rose to 2.16, whereas diagnostic ERCP increased from 1.7 to 3.62, more appropriately reflecting complexity. Complex procedures previously not catalogued were now included (e.g. gastric endoscopic submucosal dissection: 16.74)., Discussion: This novel service catalogue for GI-endoscopy almost completely covers all endoscopic procedures performed in German hospitals and assigns relative personnel-cost values based on actual physician time logs. It is to be included in the national coding recommendation and should replace all prior inventories for cost distribution. The catalogue will contribute to a more objective cost allocation and hospital reimbursement - at least until time tracking for endoscopy becomes mandatory., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: CD8+ T-cells and interleukin-2 play an important role during organ rejection in kidney transplant recipients. Numerous studies showed increased interleukin-2 levels during acute rejection. The aim of our study is to show an association between intracellular interleukin-2 in CD8+ T-cells and the incidence of those who underwent organ rejection in kidney transplant recipients., Methods: 407 transplant recipients were included into this study. The rejection incidence was investigated from the patient records. White blood cells from recipients were separated using a ficoll gradient. The cells were double-gated (CD3+ and CD8+) for the analysis of cellular percentage for intracellular interleukin-2 with a flow cytometer., Results: The percentage of CD8+ cells with detectable intracellular interleukin-2 was significantly higher in renal transplant recipients with a documented rejection compared to recipients without any history of rejection (9.06±0.50, N=133 vs. 4.28±0.24, N=274, p<0.0001, t-test). Further, there was a significant increase in patients with one (8.02±0.54, N=80, p<0.0001, t-test), two (10.40±1.17, N=33, p<0.0001, t-test) or three (11.82±1.58, N=18, p<0.0001, t-test) rejection events., Conclusions: Past studies showed, that during acute organ rejection intracellular interleukin-2 is increased in cytotoxic T-cells, supposed to be a marker for this event. We were able to show, that intracellular interleukin-2 in CD8+ T-cells is also increased after organ rejection. Furthermore it seems to depend on the quantity of rejection events. Further studies in recipients with increased intracellular interleukin-2 in cytotoxic CD8+ T-cells and documented history of organ rejection are needed to identify this as a possible risk factor for further rejection events., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Electrode materials play a key role in enhancing the electricity generation in the microbial fuel cell (MFC). In this study, a new material (Ti-TiO(2)) was used as an anode electrode and compared with a graphite electrode for electricity generation. Current densities were 476.6 and 31 mA/m(2) for Ti-TiO(2) and graphite electrodes, respectively. The PCR-DGGE analysis of enriched microbial communities from estuary revealed that MFC reactors were dominated by Shewanella haliotis, Enterococcus sp., and Enterobacter sp. Bioelectrochemical kinetic works in the MFC with Ti-TiO(2) electrode revealed that the parameters by non-linear curve fitting with the confidence bounds of 95% gave good fit with the kinetic constants of η (difference between the anode potential and anode potential giving one-half of the maximum current density) = 0.35 V, K (s) (Half-saturation constant) = 2.93 mM and J (max) = 0.39 A/m(2) for T = 298 K and F = 96.485 C/mol-e(-). From the results observed, it is clear that Ti-TiO(2) electrode is a promising candidate for electricity generation in MFC.

Purpose: The purpose of this study was to evaluate clinical outcomes, posttreatment care, and patient satisfaction with overdenture treatment in the severely resorbed mandible., Materials and Methods: Two implants were inserted in the intraforaminal region of 36 edentulous patients. Seventy-two implants were placed: 24 ITI (Institut Straumann), 24 SwissPlus (Zimmer Dental), and 24 Astra (Astra Tech). Implants were not loaded until osseointegration was complete. Following osseointegration and insertion of the prosthesis, the implants were evaluated by clinical and radiographic parameters. Clinical parameters, including Plaque Index, Sulcus Bleeding Index, peri-implant probing depth (PD), and marginal bone loss (MBL), were recorded, and any biologic and mechanical complications at baseline and recall evaluations were noted. Patient satisfaction with mastication, phonetics, retention, oral hygiene, and esthetics was also evaluated by means of a questionnaire. The results were analyzed statistically., Results: The cumulative implant survival rate after 5 years of loading was 100%. There were significant differences in mean PD values between the three implant groups at baseline and recall evaluations. Mean PD values for the Astra group were significantly higher than those for the ITI and SwissPlus groups. Although the mean MBL was within clinically acceptable levels for all groups, there were significant differences among the three groups for MBL scores between baseline and 5 years. The mean MBL for the ITI group was significantly lower than the MBL values seen for the Astra and SwissPlus groups. Over the 60-month evaluation period, the most common prosthetic complications were mandibular denture fracture and dislodgement of the female attachment., Conclusions: Mandibular implant overdenture treatment is a successful treatment modality for the severely resorbed mandible.

The aim of this study is to compare the histological grading of acute organ rejection according to the Banff score with intracellular interleukin-2 (IL-2) concentrations in cytotoxic CD8+ T cells from peripheral blood samples. 66 recipients after liver transplantation and 20 healthy controls were included into this study. Blood samples of liver transplant recipients were collected beside routine visits or, in case of suspected organ rejection, with additional liver biopsy. For cytometry, the blood cells were stained with CD3, CD8 and intracellular-IL-2. The percentage of cells with detectable intracellular IL-2 was significantly increased in patients with acute rejection (n = 7, P < 0.001, t Test) compared to recipients without rejection. The percentage of cells with detectable intracellular IL-2 (mean +/- SEM) was 7.6 +/- 0.9% in rejection patients, 2.3 +/- 0.22% in stable liver transplant recipients, and 14 +/- 2.99% in healthy controls. Intracellular IL-2 correlates to the Banff score in rejection patients (Spearmans-rho = 0.81, P < 0.05). This cytometric method shows a good sensitivity (71%) with a cut-off based on a high specificity of 95% for histological proven organ rejection in our study cohort. Measurement of intracellular IL-2 in cytotoxic CD8+ T-lymphocytes by flow cytometry correlates very well to the histological grading according to the Banff score and shows a good sensitivity and excellent specificity in acute organ rejection.

Background: Amyloidosis represents a group of different diseases characterized by extracellular accumulation of pathologic fibrillar proteins in various tissues and organs. Severe amyloid deposition in the liver parenchyma has extrahepatic involvement predominantly in the kidney or heart. We evaluated the effect of ursodeoxycholic acid, in four patients with severe hepatic amyloidosis of different etiologies, who presented with increased alkaline phosphatase and gamma-glutamyl transferase., Case Report: The study included four patients who presented with amyloidosis-associated intrahepatic cholestasis. Three of them had renal amyloidosis which developed 1-3 years before cholestasis occurred, the remaining one having intrahepatic cholestasis as the primary sign of the disease. Amyloidosis was identified from liver biopsies in all patients by its specific binding to Congo red and green birefringence in polarized light. The biochemical nature and the class of amyloid deposits were identified immunohistochemically. In addition to their regular treatment, the patients received 750 mg ursodeoxycholic acid per day. After 2-4 weeks all patients had a significant decrease of serum alkaline phosphatase and gamma-glutamyl transferase, and their general status significantly improved., Conclusion: Treatment with ursodeoxycholic acid may be beneficial in patients with hepatic amyloidosis, and do extend indications for the use of ursodeoxycholic acid in amyloidotic cholestatic liver disease.

Objective: Hyperhomocysteinemia is a described risk factor of cardiovascular diseases. The aim of this study was the treatment of hyperhomocysteinemia in liver transplant recipients with L-5-methyltetrahydrofolate (L-5-MTHF; 1 mg) vs folic acid (1 mg) vs placebo in a double-blind placebo-controlled study and to compare the relative responsiveness of these patients to L-5-MTHF and folic acid., Subjects/methods: Patients were recruited from Hepatology-Transplantation-Unit at Johann Wolfgang Goethe-University, Frankfurt. Sixty patients were included in this study and 12 patients dropped out for different reasons. The patients were treated over 8 weeks with supplemental L-5-MTHF or folic acid or placebo. Serum homocysteine (HCY) was analyzed with high-performance liquid chromatography (HPLC) beside routine lab tests., Results: We observed only a significant decrease of total serum HCY in the L-5-MTHF group during the study period (at week 0: 15+/-7.7 microM; after 8 weeks treatment: 9.41+/-2.6 microM, P<0.001). There was no significant decrease of total serum HCY neither in the folic acid group nor in the placebo group., Conclusion: The effects of L-5-MTHF are significantly more potent than folic acid itself. Therefore, lowering serum HCY in liver transplant recipients is effective with L-5-MTHF.

Objective: The aim of this study was to evaluate the role of the C677T-MTHFR (methylenetetrahydrofolate reductase)-polymorphism (CC, CT and TT) for vascular complications in liver transplant recipients., Design: Retrospective study., Setting: Hepatology-Transplantation-Unit, Johann Wolfgang Goethe-University, Frankfurt am Main., Subjects: 48 liver transplant recipients were included, no dropouts., Methods: MTHFR polymorphism was detected by PCR amplification and digestion with Hinfl restriction enzyme. Vascular complications after liver transplantation were detected from the patients' records. The total serum homocysteine (HCY) was analyzed with high-pressure liquid chromatography., Results: In the wild-type group (CC), the HCY levels were slightly high (14.0+/-1 micro M). Among the patients with the CT polymorphism, the HCY values were elevated (22.5+/-3 micro M). In the homozygous TT group, there was a significant increase (31.2+/-6 micro M, P<0.01) of the HCY values. The percentage of vascular complications was higher in the heterozygous CT (47%) and homozygous TT (62.5%) group compared with wild-type CC (21%). Patients with a homozygous TT genotype of the MTHFR polymorphism with a vascular complication had a highly significant elevated HCY level compared to the other genotype groups, both with and without any vascular complications (P<0.001). Recipients with an elevated HCY and the TT polymorphism have a higher probability of developing a vascular complication after transplantation (odds ratio: 4.3 and 11.0; 95% confidence interval: 1.15, 12.25 and 1.41, 85.24)., Conclusions: The C677T polymorphism in the MTHFR gene and subsequent elevation of the total serum HCY is significantly associated with an increased incidence of vascular complications in liver transplant recipients.

Aim: To correlate the significance of liver biochemical tests in diagnosing post orthotopic liver transplantation (OLT) biliary complications and to study their profile before and after endoscopic therapy., Methods: Patients who developed biliary complications were analysed in detail for the clinical information, laboratory tests, treatment offered, response to it, follow up and outcomes. The profile of liver enzymes was determined. The safety, efficacy and outcomes of endoscopic retrograde cholangiography (ERC) were also analysed., Results: 40 patients required ERC for 70 biliary complications. GGT was found to be > 3 times (388.1 +/- 70.9 U/mL vs 168.5 +/- 34.2 U/L, P=0.007) and SAP > 2 times (345.1 +/- 59.1 U/L vs 152.7 +/- 21.4 U/L, P=0.003) the immediate post OLT values. Most frequent complication was isolated anastomotic strictures in 28 (40%). Sustained success was achieved in 26 (81%) patients., Conclusion: Biliary complications still remain an important problem post OLT. SAP and GGT can be used as early, non-invasive markers for diagnosis and also to assess the adequacy of therapy. Endoscopic management is usually effective in treating the majority of these biliary complications.

Purpose: The objectives of this study were (1) to compare the stability, evaluated by means of resonance frequency analysis (RFA), of implants placed posterior mandibles augmented with autogenous bone harvested from the mandibular symphysis with that of implants placed in nongrafted edentulous posterior mandibles and (2) to compare peri-implant marginal bone height changes and implant failure for the 2 groups., Materials and Methods: Eight patients with thin posterior mandibular ridges (buccolingual crestal width less than 4 mm) underwent labial onlay alveolar grafting with symphyseal bone blocks 4 months prior to placement of 17 implants. Seven nongrafted patients received 18 implants in the edentulous posterior mandible; these patients served as a control group. RFA was performed the day of implant placement (baseline), 1 month postplacement, 4 months postplacement (after prosthesis delivery), and 12 months postloading. Peri-implant bone height changes at a level of 0.01 mm were assessed using periapical radiographs at baseline, the 1-month follow-up, and the 4-month follow-up. Analysis of variance was used to evaluate statistical differences within the groups, and t test was used to make comparisons between groups., Results: None of the patients presented postoperative complications or implant failure. Mean implant stability quotient (ISQ) was 63.0+/-6.0 to 70.2 +/-3.5 for the grafted group and 64.1+/-4.1 ISQ to 70.1+/-3.9 for the nongrafted group. No significant difference was found in mean ISQ between the grafted and nongrafted groups at baseline, the 1-month follow-up, 4 months postplacement, or 12 months postloading (P = .211, P = .873, P = .925, P = .735, respectively). Mean peri-implant bone loss was 0.16 +/- 0.04 mm mesially and 0.16 +/- 0.05 mm distally., Conclusion: RFA revealed no difference in implant stability between mandibular ridges augmented with autologous bone grafts at baseline or after loading.

Statement of Problem: Survival rates of implants in posterior regions vary among clinical studies. Problems occur more often in the posterior segment of the maxilla due to proximity of the maxillary sinus and reduced quality or quantity of alveolar bone., Purpose: This clinical study evaluated the treatment outcomes of 3 brands of implants in the posterior maxillae and mandibles of 63 patients. Treatment outcomes of all implants were assessed according to implant type, location, patient gender, periodontal status, and prosthesis type., Material and Methods: A total of 203 implants-105 ITI (ITI), 53 Camlog (CAM), and 45 Frialit (FRI)-were placed in 63 patients (38 women, 25 men). One hundred twelve implants were located in the posterior mandible and 91 in the posterior maxilla. All implants were longer than 10 mm and had a diameter larger than 3.5 mm. Implants in the ITI group were placed in a 1-stage surgery. The CAM and FRI groups were treated with a 2-stage surgical protocol. Implants were not loaded until osseointegration was complete, which was determined clinically and radiographically. At that point, implants were restored with 50 single crowns and 81 fixed partial dentures (FPDs). While 11 FPDs connected implants to natural teeth, 70 FPDs were supported by implants only. Standardized radiographs were made, and clinical parameters were recorded at prosthesis insertion (baseline) and at each recall evaluation (6, 12, 24, and 36 months). Plaque index (PI), sulcus bleeding index (SBI), peri-implant probing depth (PD), and radiographic marginal bone loss (MBL) levels were recorded at baseline, along with any biological and mechanical complications. Repeated-measures ANOVA, Kruskal-Wallis test, Wilcoxon signed rank test, and paired samples tests were used for statistical analysis (alpha=.05)., Results: One implant was lost during the osseointegration period in 1 woman due to infection. The cumulative implant treatment outcome was 99.3%. At the 3-year recall, plaque accumulation was significantly higher than baseline scores (P=.01, Wilcoxon signed rank test). Eight percent of the patients presented>2 mm PD at 2-year recall. The influence of observation time was found to be significant for the mean MBL values between groups (P=.001). When MBL values were compared between groups, no significant differences were found. For 1 patient in the FRI group, abutment loosening was observed and both the crown and the abutment were replaced. Patient satisfaction in all groups was high., Conclusion: The 3 brands of implants evaluated in this study exhibited similar positive treatment outcomes after 3 years.

Objectives: Homocysteine (HCY) is a sulfur-containing amino acid considered to be a marker for a relative folate deficiency. Hyperhomocysteinemia is a known risk factor for development of cardiovascular disease, vascular dementia, depression, and possibly some carcinogeneses. Liver transplant recipients have an increased risk for cardiovascular disease because of a high incidence of obesity, arterial hypertension, diabetes mellitus, and hyperlipidemia. The aim of this study is to elucidate the determinants for hyperhomocysteinemia as an additional risk factor in these patients., Materials and Methods: Seventy stable liver transplant recipients, 48 men (mean age, 50+/-11 years) and 22 women (mean age, 52+/-13 years) had their serum homocysteine levels tested after orthotopic liver transplantation. For mainstay immunosuppression, 53 patients were treated with tacrolimus, 10 with cyclosporine, 3 with mycophenolate mofetil, and 4 with sirolimus. Fasting blood samples were obtained and analyzed immediately (within 1 hour) for total serum homocysteine by high-performance liquid chromatography., Results: In all patients, mean homocysteine levels were 22.7+/-14 micromol/L (normal range, 9-15 micromol/L). Forty-six patients were found to have homocysteine levels>15 micromol/L, and all 70 recipients had homocysteine levels>9 micromol/mL. In our patients, increased homocysteine levels correlated well with body mass index and renal function. Homocysteine levels in patients receiving cyclosporine were higher than those in patients receiving tacrolimus (22.3+/-6 vs 17.9+/-12 micromol/L, P<.05)., Conclusions: Overall, homocysteine levels are significantly increased in liver transplant recipients. Homocysteine levels correlate well with obesity, renal function, and the particular immunosuppressant protocol. Therefore, a specific treatment for patients after liver transplantation (eg, one with folates) might reduce the risk of complications resulting from hyperhomocysteinemia.

Almost every patient with chronic renal failure (CRF) eventually develops secondary hyperparathyroidism (SH) unless they are treated with proper and novel medications in advanced medical centers by skilled medical personnel. Every kind of bone abnormality including skull deformities has been described in detail by almost every concerned researcher and textbook, but descriptions of this phenomenon are limited in the medical literature to the years from 1973 to 1977. To our knowledge, extensive data regarding uglifying human face appearances have not been defined so far in the literature. We are therefore making this addition to the clinical nephrology field by accumulating such data. After we found 2 consecutive peculiar and unique patients with uglifying human face appearances in 2000, we attempted to inform and draw attention to this new entity to all hemodialysis (HD) centers in Turkey, as well as in other developing countries around the world to collect data on this phenomenon. Accordingly, we visited dialysis centers and patients' houses to collect detailed information, including medical clinical histories, physical examinations, laboratory data, biographies, current medications, and so forth. We found 25 patients who had CRF, SH, short stature, extremely severe skull changes, maxillary and mandibular bone changes, teeth/dental abnormalities, and soft and innocuous tumoral tissues in the mouth (hence, uglifying the appearance of the face), fingertip changes, severe psychologic problems, and depression. It appears that patients with CRF may have a new syndrome of bone deformities that have long been neglected, ignored, and forgotten since the mid-1970s when they were first described. This is vital and critical information for the clinical status of patients who suffered from the syndrome that we have named Sagliker syndrome (SS), and we believe there are many more patients in the world who are suffering from it.

Background: There is an increasing evidence, stemming from epidemiological studies as well as studies performed in human biopsies and animal and cell culture models, suggesting that folate is chemopreventive in colonic carcinogenesis. Hyperhomocysteinemia is frequently associated with folate deficiency. Homocysteine, an amino acid, is metabolized to methionine in a 5-methyltetrahydrofolate (5-MTHF) dependent reaction., Aim of the Study: The aim of this study was i) to evaluate the effects of folate and its metabolites on growth and cell cycle progression in human colon cancer cells (Caco-2) in culture, and ii) to assess the effects of exogenous homocysteine on colon cancer cell proliferation. iii) Having found that homocysteine enhances colon cancer cell growth while metabolites of folate inhibit cell proliferation, we investigated the effects of simultaneous treatment in colon cancer cells., Methods: Caco-2 cells were incubated either with homocysteine (0.1-10 microM), and/or with folic acid and its metabolites (0.625-10 microg/ml). Cell proliferation was determined after 24 h and 48 h by measuring 5- bromo-2'-desoxyuridine (BrdU) incorporation. Additionally, the cells were trypsinized and prepared for cell cycle determination using propidium iodide for DNA staining. The stained cells were analyzed using a flow cytometer., Results: Folate inhibited cell proliferation moderately within 24 h. Its metabolites, dihydrofolate and 5-MTHF were more potent inhibitors of cell growth. Treatment with folate and 5-MTHF resulted in the accumulation of cells in G1-G0 phase of the cell cycle and decreased the number of cells in G2-M phase. In addition, cells treated with 5-MTHF were predominantly accumulated in the S-phase. There was no difference in cell cycle progression of Caco-2 cells treated with homocysteine in comparison to controls. In homocysteine-treated cells, both folate and 5-MTHF reversed the homocysteine-induced enhancement of growth. In contrast, folate reduced the Caco-2 cell growth rate to control values and 5-MTHF depleted growth of homocysteine-treated cells to levels significantly lower than controls., Conclusions: Our data suggest that 5-MTHF, being the key metabolite in both the folate and homocysteine metabolic pathway, is the main modulator of growth-promoting actions of homocysteine as well as antiproliferative effects of folate in colon cancer cells.

In this study we characterized a model of human peritoneal macrophages maintained in culture for up to 48 h that can be used to study different functions of this cell population in vitro. The cells remained viable and functionally active over time, with well-preserved phagocytic properties. They expressed a macrophage marker, CD14. Once in culture, human peritoneal macrophages secreted C1q and nitric oxide in a pattern described in murine, guinea pig, and rat peritoneal macrophages. The described model can be used to study physiology and pathophysiology of peritoneal macrophages in vitro, offering all the advantages of the use of a human cell population.

The complement system plays an important role in the humoral immune response. Activation of the classical complement pathway is mediated by its subcomponent, C1q, which is involved in the pathogenesis of several autoimmune disorders. Among the main C1q-synthesising tissues, macrophages have been attributed as the main source. We investigated the effects of anti-inflammatory drugs (methylprednisolone and acetylsalicylic acid (ASA)) on C1q secretion in human peritoneal macrophages in vitro. The macrophages were isolated from peritoneal lavage fluid of patients with end-stage renal disease undergoing continuous ambulatory peritoneal dialysis, and were maintained in culture for up to 6 days. ASA decreased while methylprednisolone increased C1q secretion from human peritoneal macrophages in vitro, which correlated well with the percentage of CD14 positive cells after treatment. We conclude that different response of the macrophages to treatment with methylprednisolone and ASA may point out to the importance of macrophage activation after treatment, as well as an increased abundance of membrane C1q accompanied by increased phagocytosis.

Piceatannol, a naturally occurring analog of resveratrol, was previously identified as the active ingredient in herbal preparations in folk medicine and as an inhibitor of p72(Syk). We studied the effects of piceatannol on growth, proliferation, differentiation and cell cycle distribution profile of the human colon carcinoma cell line Caco-2. Growth of Caco-2 and HCT-116 cells was analyzed by crystal violet assay, which demonstrated dose- and time-dependent decreases in cell numbers. Treatment of Caco-2 cells with piceatannol reduced proliferation rate. No effect on differentiation was observed. Determination of cell cycle distribution by flow cytometry revealed an accumulation of cells in the S phase. Immunoblotting demonstrated that cyclin-dependent kinases (cdk) 2 and 6, as well as cdc2 were expressed at steady-state levels, whereas cyclin D1, cyclin B1 and cdk 4 were downregulated. The abundance of p27(Kip1) was also reduced, whereas the protein level of cyclin E was enhanced. Cyclin A levels were enhanced only at concentrations up to 100 micromol/L. These changes also were observed in studies with HCT-116 cells. On the basis of our findings, piceatannol can be considered to be a promising chemopreventive or anticancer agent.

Resveratrol is a naturally occurring polyphenol with cancer chemopreventive properties. The objective of the current study was to investigate the effect of resveratrol on the human colonic adenocarcinoma cell line Caco-2. The compound inhibited cell growth and proliferation of Caco-2 cells in a dose-dependent manner (12.5-200 micromol/L) as assessed by crystal violet assay, [(3)H]thymidine and [(14)C]leucine incorporation. Furthermore, apoptosis was determined by measuring caspase-3 activity, which increased significantly after 24 and 48 h of treatment with 200 micromol/L resveratrol. Perturbed cell cycle progression from the S to G2 phase was observed for concentrations up to 50 micromol/L, whereas higher concentrations led to reversal of the S phase arrest. These effects were specific for resveratrol; they were not observed after incubation with the stilbene analogs stilbenemethanol and rhapontin. Levels of cyclin D1 and cyclin-dependent kinase (cdk) 4 proteins were decreased, as revealed by immunoblotting. In addition, resveratrol enhanced the expression of cyclin E and cyclin A. The protein levels of cdk2, cdk6 and proliferating cell nuclear antigen were unaffected. Similar results were obtained for the colon carcinoma cell line HCT-116, indicating that cell cycle inhibition by resveratrol is independent of cyclooxygenase inhibition. The phosphorylation state of the retinoblastoma protein in Caco-2 cells was shifted from hyperphosphorylated to hypophosphorylated at 200 micromol/L, which may account for reversal of the S phase block at concentrations exceeding 50 micromol/L. These findings suggest that resveratrol exerts chemopreventive effects on colonic cancer cells by inhibition of the cell cycle.

Mevastatin is an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis. Butyrate, a short-chain fatty acid, reduces proliferation and induces differentiation of human colon cancer cells. The aim of our study was to determine the effect of mevastatin, alone or in combination with butyrate, on proliferation, the cell cycle and apoptosis in the human colorectal carcinoma cell line Caco-2. In this report we show that mevastatin combined with butyrate synergistically suppressed growth of Caco-2 cells in a dose- and time-dependent manner. In addition, incubation with mevastatin arrested cells in the G1 phase of the cell cycle after 24 h with a switch to the G2/M phase after 72 h. This was accompanied by a down-regulation of cyclin-dependent kinases (cdk) 4 and cdk 6 as well as cyclin D1, while cdk 2 and cyclin E protein levels remained unchanged during mevastatin treatment. Cell cycle inhibitors p21 and p27 were significantly upregulated by mevastatin. The proapoptotic properties of mevastatin were further enhanced by co-incubation with butyrate. Lastly, the effects of mevastatin could be reversed by addition of mevalonate, but not farnesyl- or geranylgeranylpyrophosphate, intermediate products of cholesterol synthesis, to the medium. These results suggest that HMG-CoA reductase inhibitors like mevastatin may enhance the antiproliferative effect of butyrate in colon cancer cells via induction of apoptosis together with a G0/G1 cell cycle arrest.