Aspects in the interdisciplinary decision-making for surgical intervention in ulcerative colitis and its complications.

Ulcerative colitis (UC) is a chronic inflammation of the large bowel, predominantly affecting young adults of 20 to 30 years of age. Even though the majority of patients with limited and extensive UC can be managed medically, 20 to 30 % will require surgical intervention at some point in their life to gain control of the inflammatory process. The most common reason for urgent and emergency surgery is a lack of response to maximal medical inpatient therapy after five to ten days. Other indications include hemorrhage, free perforation, sepsis, and toxic megacolon. Procedure of choice for the majority of surgeons is open or laparoscopic subtotal colectomy and end ileostomy, with or without exteriorization of the rectal stump. The laparoscopic approach requires more time, but allows for faster return of bowel function and discharge from the hospital. Creation of a definite restoration in form of a J pouch should be delayed for at least three months. Indications for elective surgical intervention include cancer, dysplasia associated lesion or mass, and stricture. Preferably, the J pouch and Brooke ileostomy are performed in two stages, with a takedown of the ileostomy several months later. A single-stage operation is associated with increased anastomotic dehiscence, sepsis, and long-term pouch failure. The laparoscopic creation of a J pouch is largely dependent on the surgeon's experience, but results in a number of advantages, including faster return of bowel function, tolerance of diet, and discharge. Regardless of emergency, urgent, or elective surgical intervention, early involvement of a team of gastroenterologist, surgeon, nutritionist, and stoma nurse is essential in the management of severe UC to maximize a satisfactory patient outcome.

The del/del genotype of the nuclear factor-kappaB -94ATTG polymorphism and its relation to aggressive periodontitis.

BACKGROUND AND OBJECTIVE: Periodontitis is influenced by specific host-dependent immune responses. Periodontopathogens induce innate immune responses, amongst others, via toll-like receptor 2 (TLR2), resulting in activation of the nuclear transcription factor nuclear factor-kappaB (NF-kappaB). The aim of this case-control study was to evaluate links between genetic variants of these genes and chronic/aggressive periodontitis in a multivariate model. MATERIAL AND METHODS: A total of 141 patients with periodontitis (63 with chronic periodontitis and 78 with aggressive periodontitis) and 81 controls without periodontitis were included in the study. Polymorphisms in TLR2 (Arg677Trp, Arg753Gln) and in NF-kappaB (-94ins/delATTG) were determined by restriction fragment length polymorphism and fragment length analyses, respectively. Subgingival bacterial colonization was evaluated using a PCR/DNA probe test (micro-Ident). RESULTS: Although there was no association of the TLR2 polymorphism Arg753Gln with periodontitis, heterozygous carriers (Arg/Gln) were at a higher risk for colonization with bacteria of the 'red complex' (corrected p-value = 0.042). The del/del genotype of the NF-kappaB polymorphism was associated with aggressive periodontitis considering age, gender, smoking and approximal plaque index as potential confounders (odds ratio = 2.81, p = 0.035, 95% confidence interval: 1.08-7.33). del/del carriers had a higher risk for subgingival colonization with Aggregatibacter actinomycetemcomitans (odds ratio = 2.36, p = 0.030, 95% confidence interval: 1.09-5.1; adjusted for age, gender, smoking and pocket depth(bacteria)). CONCLUSIONS: The del/del genotype of NF-kappaB was shown to be associated with the occurrence of aggressive periodontitis.

Interleukin-2 -330 and 166 gene polymorphisms in relation to aggressive or chronic periodontitis and the presence of periodontopathic bacteria.

BACKGROUND AND OBJECTIVE: As a pro-inflammatory cytokine, interleukin-2 mediates the activation, growth and differentiation of T and B lymphocytes and natural killer cells. Promoter polymorphisms of the interleukin-2 gene have been associated with altered interleukin-2 production or identified as prognostic markers for various infectious diseases. Therefore, the aim of this study was to evaluate two polymorphisms at positions -330 T/G and 166 G/T in patients with generalized chronic periodontitis (n = 58) or generalized aggressive periodontitis (n = 73) in comparison with periodontitis-free controls (n = 69). MATERIAL AND METHODS: Both interleukin-2 polymorphisms were analyzed using the polymerase chain reaction with sequence-specific primers. Distributions of single alleles, genotypes and haplotypes were calculated using the chi-square test. Risk factor analyses were carried out by logistic regression with respect to established cofactors for periodontitis. The presence of subgingival bacteria in an individual were analyzed using a molecular biological method (the micro-Ident test). RESULTS: The interleukin-2 genotype -330 TG occurred less frequently in patients with chronic periodontitis (25.9% vs. 49.3%). Moreover, this genotype decreased the adjusted odds ratio for chronic periodontitis (odds ratio = 0.394), whereas the interleukin-2 genotype 166 TT and the haplotype combination interleukin-2 -330,166 TT : TT were associated with an increased adjusted odds ratio (odds ratio = 2.82 or 2.97). For the latter interleukin-2 combination, a positive association for the subgingival presence of Porphyromonas gingivalis (81.3% vs. 59.5%) and bacteria of the 'red complex' (78.1% vs. 56.0%) was shown. CONCLUSION: The interleukin-2 genotypes -330 TG and 166 TT, as well as the combination genotype interleukin-2 TT : TT, could be putative prognostic factors for chronic periodontitis.

[Multitalented lymphostatin]. / Lymphostatin--ein Multitalent.

INTRODUCTION: Gastrointestinal infections are a significant cause of diarrhea and a worldwide problem with annually one billion illnesses and 3 to 4 million deaths. Gram negative bacteria like Enteropathogenic E. coli (EPEC) in developing countries and Enterohemorrhagic E. coli (EHEC) in the developed world are responsible for the majority of acute diarrheal episodes, especially among children less than three years of age. Pathogenic E. coli are supplied with an arsenal of effector proteins to modify and neutralize specific cellular functions of the host organism. METHODS: Based on personal and extensively published results we provide a selected overview of Gram negative virulence functions with a focus on lymphostatin. RESULTS: Lymphostatin is an effector protein encoded by lifA/efa-1 (lymphocyte inhibitory factor A/ EHEC factor for adherence). lifA/efa-1 and homologous genes have been identified in EPEC, EHEC, and mouse pathogen Citrobacter rodentium, as well as various Chlamydia strains. Multiple groups have shown that in various EHEC strains lifA/efa-1 is part of a larger pathogenicity island responsible for increased virulence. Statistically, DNA Microarray analysis associated lifA/efa-1 as the single most imortant gene with diarrhea caused by EPEC. Interestingly, lifA/efa-1 encodes for two critical enzymatic activities that have been identified in other pathogenic bacteria: glucosyltransferase- in Clostridium- and protease activity in Yersinia strains. In vitro studies identified lymphostatin as an effector protein with an immunosuppressive effect on peripheral blood and gastrointestinal mucosa T lymphocytes. Further, lymphostatin regulates the barrier function of epithelial monolayer cultures: activation of small GTPase RhoA and inhibition of Cdc42 lead to disassembly of adherens junctions and tight junctions, respectively. Besides an effect on immune and epithelial barrier function, lymphostatin also functions as an adhesion factor for EPEC and EHEC, is essential for colonization of mouse and calf intestine, and regulates bacterial effector proteins. SUMMARY: Lymphostatin is a common toxin in Gram negative bacteria with multiple functions: cell adhesion, immunosuppression, disruption of epithelial barrier function, and intestinal colonization.

Impact of genetic variants of CD14 and TLR4 on subgingival periodontopathogens.

CD14 and toll-like receptor 4 (TLR4) are involved in host's immune response to bacterial pathogens including periodontal bacteria. Functional important gene polymorphisms are described for both genes. The aim of this study was to evaluate links between genetic polymorphisms of CD14 and TLR4 and risk markers of periodontitis in a multivariate model. One hundred and thirty-three periodontitis patients (chronic: n = 60, aggressive: n = 73) and 80 healthy controls without periodontitis were included in the study. Polymorphisms in CD14 c.-159C>T and in TLR4 Asp299Gly, Thr399Ile were determined by restriction fragment length polymorphism analyses. The clinical investigation included smoking status, plaque and bleeding indexes, pocket depth and attachment loss. Subgingival bacterial colonization was analysed molecularbiologically using the micro-Ident test. Prevotella intermedia occurred less frequently in individuals positive for the TT genotype of CD14 in bivariate analysis (odds ratio = 0.36%, confidence interval: 0.14-0.91, P = 0.045). In binary logistic regression analyses, the occurrence of this bacterium was significantly decreased in TT carriers (odds ratio = 0.31%, confidence interval: 0.81-0.12, P = 0.017) considering age, smoking and maximum clinical attachment loss at microbial test site as confounding factors. However, no significant association with chronic and or aggressive periodontitis and polymorphisms in CD14 and TLR4 could be proven. Although the CD14 c.-159C>T polymorphism could be shown to be associated with subgingival colonization with P. intermedia, there is no evidence that CD14 and TLR4 polymorphisms investigated are independent risk factors for chronic or aggressive periodontitis in German periodontitis patients.

The interleukin-10 promoter haplotype ATA is a putative risk factor for aggressive periodontitis.

BACKGROUND AND OBJECTIVE: Interleukin-10 has been described as an anti-inflammatory cytokine and a B-cell proliferation factor. Promoter polymorphisms of the interleukin-10 gene have been associated with altered interleukin-10 expression. Therefore, the aim of this study was to evaluate three polymorphisms at positions -1082G>A, -819C>T and -590C>A in patients with generalized chronic periodontitis (n = 27) and generalized aggressive periodontitis (n = 32) in comparison with periodontitis-free controls (n = 34). MATERIAL AND METHODS: Interleukin-10 promoter polymorphisms were analyzed by polymerase chain reaction with sequence-specific primers (PCR-SSP). Distributions of single alleles, genotypes and haplotypes were calculated by the chi-square test. Risk factor analyses were carried out by logistic regression. Subgingival bacteria were subjected to molecular biological analyses using the micro-Ident test. RESULTS: The combination ATA/ATA was found only in patients with aggressive periodontitis (15.6 vs. 0.0%, p = 0.023). Taking into account age, gender, smoking and plaque level, an increased odds ratio (3.7, p = 0.04) for aggressive periodontitis was shown for subjects with the haplotype ATA. Prevotella intermedia was found to be decreased in ACC- positive (41.3 vs. 66.7%, p = 0.022), ATA-positive (33.3 vs. 57.1%, p = 0.032) and ACC/ATA-positive (20.0 vs. 55.9%, p = 0.002) individuals. In GCC/GCC-positive subjects, P. intermedia occurred more frequently (86.7 vs. 42.3%, p = 0.002). CONCLUSION: The haplotype ATA, which is known as a 'low interleukin-10 producer' is a putative risk indicator for generalized aggressive periodontitis.

A randomized multicentre trial of insulin glargine compared with NPH insulin in people with type 1 diabetes.

BACKGROUND: To compare insulin glargine with NPH human insulin for basal insulin supply in adults with type 1 diabetes. METHODS: People with type 1 diabetes (n = 585), aged 17-77 years, were randomized to insulin glargine once daily at bedtime or NPH insulin either once- (at bedtime) or twice-daily (in the morning and at bedtime) according to their prior treatment regimen and followed for 28 weeks in an open-label, multicentre study. Both groups continued with pre-meal unmodified human insulin. RESULTS: There was no significant difference between the two insulins in change in glycated haemoglobin from baseline to endpoint (insulin glargine 0.21 +/- 0.05% (mean +/- standard error), NPH insulin 0.10 +/- 0.05%). At endpoint, self-monitored fasting blood glucose (FBG) had decreased similarly in each group (insulin glargine -1.17 +/- 0.12 mmol/L, NPH insulin -0.89 +/- 0.12 mmol/L; p = 0.07). However, people on >1 basal insulin injection per day prior to the study had a clinically relevant decrease in FBG on insulin glargine versus NPH insulin (insulin glargine -1.38 +/- 0.15 mmol/L, NPH insulin -0.72 +/- 0.15 mmol/L; p < 0.01). No significant differences in the number of people reporting >or=1 hypoglycaemic episode were found between the two groups, including severe and nocturnal hypoglycaemia. Insulin glargine was well tolerated, with a similar rate of local injection and systemic adverse events versus NPH insulin. CONCLUSIONS: A single, bedtime, subcutaneous dose of insulin glargine provided a level of glycaemic control at least as effective as NPH insulin, without an increased risk of hypoglycaemia.

A large toxin from pathogenic Escherichia coli strains that inhibits lymphocyte activation.

The mechanisms by which bacteria resist cell-mediated immune responses to cause chronic infections are largely unknown. We report the identification of a large gene present in enteropathogenic strains of Escherichia coli (EPEC) that encodes a toxin that specifically inhibits lymphocyte proliferation and interleukin-2 (IL-2), IL-4, and gamma interferon production in response to a variety of stimuli. Lymphostatin, the product of this gene, is predicted to be 366 kDa and shares significant homology with the catalytic domains of the large clostridial cytotoxins. A mutant EPEC strain that has a disruption in this gene lacks the ability to inhibit lymphokine production and lymphocyte proliferation. Enterohemorrhagic E. coli strains of serotype O157:H7 possess a similar gene located on a large plasmid. Loss of the plasmid is associated with loss of the ability to inhibit IL-2 expression while transfer of the plasmid to a nonpathogenic strain of E. coli is associated with gain of this activity. Among 89 strains of E. coli and related bacteria tested, lifA sequences were detected exclusively in strains capable of attaching and effacing activity. Lymphostatin represents a new class of large bacterial toxins that blocks lymphocyte activation.

Products of enteropathogenic E. coli inhibit lymphokine production by gastrointestinal lymphocytes.

Previously we have shown that lysates of enteropathogenic Escherichia coli (EPEC) inhibit lymphokine production by mitogen-activated peripheral blood mononuclear cells (PBMCs). The aim of the present study was to determine whether products of EPEC alter lymphokine expression by gastrointestinal mucosal lymphocytes. Lysates from EPEC clones inhibited mitogen-stimulated interleukin-2 (IL-2), IL-4, IL-5, and interferon-gamma (IFN-gamma) but not IL-8 mRNA expression by lamina propria mononuclear cells isolated from surgically resected colon specimens. Inhibitory lysates did not significantly change CD25 expression on either CD4, CD8, or CD45R0 lymphocytes by flow cytometry. Bacterial supernatants of EPEC inhibited IL-2 and IL-5 protein secretion by mitogen-stimulated PBMCs. EPEC lysates inhibited IL-2 mRNA expression induced by lysates of nonpathogenic E. coli. In conclusion, EPEC contains a novel gene(s) that encodes factors that selectively inhibit IL-2, IL-4, IL-5, and IFN-gamma expression by mucosal mononuclear cells without affecting CD25 or IL-8 expression. Thus enteric bacteria can produce factors that may regulate the function of the gastrointestinal mucosal immune system.

Major pathways of mucosal immunity and inflammation: cell activation, cytokine production and the role of bacterial factors.

The gastrointestinal mucosal immune system contains a large, complex mixture of cells that play an essential role in host defence against pathogens and in maintaining the normal balance of tolerance and immunity to constituents of the gastrointestinal lumen. Cells are organized in specialized structures: Peyer's patches (which are important in initiating immune responses and in non-organized compartments) and the lamina propria, where specialized, differentiated cells carry out effector functions. Many of the specialized functions of cells in this system depend on the release of cytokines and other mediators. Recent studies have demonstrated the importance of the gastrointestinal flora in modulating the activity of the mucosal immune cells and exacerbating gastrointestinal inflammation. The function of gastrointestinal immune cells and their mediators appear to be altered in inflammatory bowel diseases and offer potential targets for pharmacological intervention.

Products of enteropathogenic Escherichia coli inhibit lymphocyte activation and lymphokine production.

The aim of this study was to determine whether products of enteric bacteria are able to regulate lymphocyte activation and cytokine production. Whole bacteria and bacterial lysates from different strains of Escherichia coli were tested for their ability to inhibit cytokine production by peripheral blood mononuclear cells as determined by reverse transcription-PCR, Northern (RNA) blotting of cellular RNA, or enzyme-linked immunosorbent assay for cytokine protein. Lysates from two pathogenic strains of E. coli, enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli, inhibited mitogen-stimulated expression of interleukin-2 (IL-2), IL-4, IL-5, and gamma interferon. IL-1 beta, IL-6, IL-8, IL-10, IL-12, and Rantes mRNA expression was not affected. The inhibitory activity was dose dependent, protease and heat sensitive, nondialyzable, and not due to cellular toxicity. The inhibitory activity remained in EPEC strains having mutations in known virulence factors. Nonpathogenic E. coli HB101 transformed with a 22-kb cosmid clone derived from EPEC chromosomal DNA expressed the inhibitory activity. Thus, certain strains of pathogenic E. coli express a protein or proteins encoded by chromosomal genes that selectively inhibit lymphocyte activation and lymphokine production. Therefore, immunosuppressive factors produced by pathogenic bacteria could be important in modifying gastrointestinal immune responses in enteric bacterial infections or gastrointestinal autoimmune diseases.

Fate of interleukin-6 in the rat. Involvement of skin in its catabolism.

Iodinated recombinant human interleukin-6 (125I-rhIL-6) was intravenously injected into rats and its fate was studied during 24 h. Between 10-20 min after a single-dose injection, 125I-rhIL-6 accumulated in liver as previously reported [Castell et al. (1988) Eur. J. Biochem. 177, 357-361]. After 1 h, the radioactivity disappeared from the liver and accumulated in skin, reaching 35% of injected 125I-rhIL-6 5-8 h after injection. No comparable accumulation of radioactivity was found in skin when [125I]iodide or rat serum 125I-albumin was administered. Finally the radioactivity was detected as [125I]iodide in urine. Autoradiographic analysis of skin sections 5 h after 125I-rhIL-6 injection showed radioactivity in the interstitium. When the experiments were carried out with [35S]rhIL-6, essentially the same results were obtained: a decrease in radioactivity in the liver after 20 min, and a substantial increase in skin 7 h after injection. In vitro experiments showed that 125I-rhIL-6 is degraded by rat and human fibroblasts, whereas no degradation was observed with rat hepatoma cells (Fao) or human hepatocytes. These observations suggest the involvement of skin in the catabolism of IL-6.

Fate and biological action of human recombinant interleukin 1 beta in the rat in vivo.

The plasma half life of recombinant human interleukin 1 beta (rhIL 1 beta) was determined in rats by measuring the disappearance of the radioactivity of 125I-labeled rhIL 1 beta from the circulation. The plasma clearance showed a biphasic behavior: an initial fast disappearance (half life of about 3 min) was followed by a second slower one (half life of about 4 h). Twenty minutes after a single-dose injection of 125I-labeled rhIL 1 beta most of the radioactivity was concentrated in kidneys, liver and intestine. rhIL 1 beta induced the synthesis of alpha 1-acid glycoprotein (AGP), alpha 1-cysteine proteinase inhibitor (CPI) and beta-fibrinogen mRNA in liver. Half maximal stimulation was elicited by approximately 3000 U of rhIL 1 beta per animal. The mRNA changes for AGP and CPI were followed by corresponding protein increases in serum. Twenty hours after rhIL 1 beta injection, serum AGP rose from 0.7 to 2.5 mg/ml. CPI increased from 0.3 to 1.9 mg/ml 25 h after administration of rhIL 1 beta. Within 20 h after rhIL 1 beta injection, albumin serum concentration showed a strong decrease, preceded by a reduction in hepatic albumin mRNA levels. Neither changes in albumin synthesis nor degradation can explain this decrease suggesting that other mechanisms such as increased transvascular permeability are involved.

Regulation of alpha 2-macroglobulin gene expression by interleukin-6 (BSF-2/HSF).

In rat hepatocyte primary cultures recombinant human interleukin-6 (rhIL-6) induced alpha 2-macroglobulin (alpha 2M) synthesis 54-fold. Half-maximal induction was achieved at a rhIL-6 concentration of 30 pM. RhIL-1 beta led only to a 2-fold increase in alpha 2M synthesis, but strongly impaired the action of IL-6. Intraperitoneal injection of rhIL-6 into male rats resulted in a 19.7-fold increase of alpha 2M mRNA already after 4h. In contrast, alpha 2M mRNA levels (50-fold increase) were reached between 16 and 24 h after intramuscular injection of turpentine. Whereas turpentine-induced inflammation resulted in an increased alpha 2M synthesis in male and female rats, rhIL-6 injection had no effect in female rats. The increases after rhIL-6 administration in mRNA concentrations were followed by corresponding changes in alpha 2M levels in serum. By Northern analysis it was demonstrated that LPS-stimulated human monocytes synthesize IL-6 mRNA. The 5'-end of the rat alpha 2M gene has been isolated and the first 3 exons and 166 base pairs of the 5'-flanking region were identified by a combination of oligonucleotide hybridization and DNA sequencing. The transcriptional start site was determined by RNase protection as well as by primer extension experiments. 5'-CATAAAG-3' and 5'-TCAAAA-3' were found as TATA- and CAAT-box equivalent sequences, respectively. Furthermore, a potential glucocorticoid binding site (5'-TGTTCT-3') was localized on the antisense strand of the alpha 2M gene.

Induction of alpha 1-acid glycoprotein by recombinant human interleukin-1 in rat hepatoma cells.

The induction of alpha 1-acid glycoprotein mRNA by recombinant murine interleukin-1, recombinant human interleukin-1 alpha, and recombinant human interleukin-1 beta has been studied in the rat hepatoma cell line Fao. Whereas the stimulatory capacities of recombinant human interleukin-1 alpha and recombinant murine interleukin-1 were almost identical, the concentrations of recombinant human interleukin-1 beta needed for half-maximal induction of alpha 1-acid glycoprotein mRNA were lower by three orders of magnitude. A 60-fold increase in alpha 1-acid glycoprotein mRNA levels was observed 18 h after the addition of recombinant interleukin-1 beta. In parallel albumin mRNA levels decreased to about 30%. The alpha 1-acid glycoprotein mRNA induction was strictly dependent on the presence of dexamethasone. For a full stimulation dexamethasone concentrations of greater than 10(-7) M were needed, whereas concentrations of less than 10(-12) M were ineffective. The increase in alpha 1-acid glycoprotein mRNA after recombinant human interleukin-1 beta was followed by a 36-fold stimulation in alpha 1-acid glycoprotein synthesis and secretion. When protein synthesis was blocked by either cycloheximide, puromycin, or emetine, the induction of alpha 1-acid glycoprotein mRNA by recombinant human interleukin-1 beta was impaired suggesting the involvement of a short-lived protein in the induction of alpha 1-acid glycoprotein mRNA.

Induction of rat acute-phase proteins by interleukin 6 in vivo.

Recombinant human interleukin 6 (rhIL 6) was injected i.p. into male Wistar rats to investigate its role as a mediator of the acute-phase response. Hepatic mRNA levels of beta-fibrinogen, alpha 2-macroglobulin, cysteine proteinase inhibitor, alpha 1-acid glycoprotein and albumin were measured at different times after the administration of rhIL 6. Maximal increases of mRNA concentrations were observed already 4 h after the injection of rhIL 6 leading to 4.8-, 19.7-, 10- and 16-fold stimulations in mRNA levels of beta-fibrinogen, alpha 2-macroglobulin, cysteine proteinase inhibitor or alpha 1-acid glycoprotein, respectively. The rhIL 6-induced stimulation of acute-phase protein mRNA was much more rapid than the acute-phase induction after turpentine, where maximal mRNA levels were found between 16 and 24 h. For all acute-phase proteins studied, the stimulation of mRNA synthesis was found to be dependent on the dose of rhIL 6 injected. In the case of alpha 2-macroglobulin mRNA a sex-specific induction by rhIL 6 was found. Only male rats showed an acute-phase response, whereas in female rats an acute-phase reaction of alpha 2-macroglobulin mRNA was not inducible by IL 6. The increases in mRNA levels of the acute-phase proteins studied were followed by corresponding changes of the proteins in the serum determined by rocket immunoelectrophoresis. It is concluded that IL 6 represents a potent mediator of the acute-phase response in the rat.