[Thrombotic occlusion of the extracorporeal circulation during hepatic chemosaturation despite targeted anticoagulation : A case report]. / Thrombotischer Verschluss der extrakorporalen Zirkulation während hepatischer Chemosaturation trotz zielgerechter Antikoagulation : Ein Fallbericht.

Percutaneous hepatic chemosaturation is a treatment option for unresectable primary or secondary liver tumors. In this procedure the part of the inferior vena cava (VCI) that collects blood from the hepatic veins is isolated using a double balloon catheter. Like this, systemic distribution of the chemotherapeutic agent melphalan which is administered via the hepatic artery can be prevented. After passage through the liver and drainage from the retrohepatic VCI, the chemosaturated blood passes through two extracorporeal filters. Subsequently, the filtered blood is returned via the jugular vein. The procedure is often accompanied by severe hemodynamic instability, the cause of which is still not completely understood. In addition, coagulation management of extracorporeal circulation is often challenging. The authors report a case in which a thrombus formed in the returning leg of the extracorporeal circulation despite sufficient activated clotting time (ACT). Targeted problem search and resolution were necessary simultaneously to hemodynamic stabilization and interdisciplinary collaboration to successfully perform the intervention and provide the patient with safe treatment.

[Safety and efficacy of en bloc vs. conventional transurethral resection of bladder tumors: a meta-analysis and systematic review]. / Sicherheit und Effizienz der en bloc vs. konventionellen transurethralen Resektion von Blasentumoren: eine Metaanalyse und systematic Review.

BACKGROUND: En bloc tumor resection of bladder tumors (ERBT) is a novel alternative procedure to conventional resection of bladder tumor (cTURBT), which might help to address common problems of the standard method, such as inadequate detrusor muscle in specimens, high re-resection rates and high recurrence rates. OBJECTIVE: To analyze current data on ERBT in efficacy and safety compared to cTURBT. DATA SOURCES: PubMed. STUDY SELECTION: Two independent authors identified trials based on keywords and inclusion criteria. A third author was consulted in case of discrepancies. Screening keywords: ERBT, en bloc transurethral resection of bladder tumor, TURBT en bloc. A meta-analysis of 13 studies was performed. The effect size was estimated based on odds ratios and mean differences including their corresponding two-sided 95% confidence intervals. DATA SYNTHESIS: The analyzed studies comprised a homogenous collective in terms of tumor size, tumor multiplicity and tumor stage. Operation time did not significantly differ between the methods. Differences were observed in hospitalization and catheterization time in favor of ERBT. Reported complications did not show clear differences. There was significantly more detrusor muscle in the specimens in the ERBT group. No significant differences were found in recurrence up to 2 years of follow-up. CONCLUSION: ERBT is a safe alternative to conventional TURBT with promising features regarding effective resection of detrusor muscle. More standardized data on recurrence rates, different resection modalities and resection margin results are needed.

Enhanced Cardiac S100A1 Expression Improves Recovery from Global Ischemia-Reperfusion Injury.

Gene-targeted therapy with the inotropic Ca2 + -sensor protein S100A1 rescues contractile function in post-ischemic heart failure and is being developed towards clinical trials. Its proven beneficial effect on cardiac metabolism and mitochondrial function suggests a cardioprotective effect of S100A1 in myocardial ischemia-reperfusion injury (IRI). Fivefold cardiomyocyte-specific S100A1 overexpressing, isolated rat hearts perfused in working mode were subjected to 28 min ischemia (37 °C) followed by 60 min reperfusion. S100A1 overexpressing hearts showed superior hemodynamic recover: Left ventricular pressure recovered to 57 ± 7.3% of baseline compared to 51 ± 4.6% in control (p = 0.025), this effect mirrored in LV work and dP/dt(max). Troponin T and lactate dehydrogenase was decreased in the S100A1 group, as well as FoxO pro-apoptotic transcription factor, indicating less tissue necrosis, whereas phosphocreatine content was higher after reperfusion. This is the first report of a cardioprotective effect of S100A1 overexpression in a global IRI model.

[Assessment of kidney function : Creatinine is not the whole story]. / Beurteilung der Nierenfunktion : Kreatinin ist nicht alles.

Chronic renal insufficiency has a high prevalence and leads not only to a severe impairment in the quality of life but also to a higher mortality, mainly due to cardiovascular complications; however, in the early stages where there is still a chance for a therapeutic intervention, it is often underestimated because depending on endogenous factors (e.g. age and muscle mass), serum creatinine could falsely remain in the normal range while kidney function is already impaired. An exact measurement of the glomerular filtration rate (GFR) using radionuclide techniques is cumbersome and usually confined to rare cases, such as in clinical studies. Creatinine clearance measurement by 24-h urine collection requires good patient instructions and is error prone, thus it is limited to special circumstances. In routine clinical practice, estimation of the GFR by calculation algorithms provides the best approach. In recent years the chronic kidney disease epidemiology collaboration (CKD-EPI) formula has become established as the most accurate method. This should be used for screening and continuous surveillance. In addition, urinalysis including dipstick tests and urinary microscopy represent non-invasive, technically simple and economic screening tools. Due to its semiquantitative nature, the results of urinalysis should only to be interpreted after comprehensive consideration of the diagnostic and technical limitations, which are reviewed in this article.

[Bladder neck sclerosis following prostate surgery : Which therapy when?] / Blasenhalssklerose nach Prostataeingriffen : Wann welche Therapie?

Secondary bladder neck sclerosis represents one of the more frequent complications following endoscopic, open, and other forms of minimally invasive prostate surgery. Therapeutic decisions depend on the type of previous intervention (e.g., radical prostatectomy, TURP, HoLEP, radiotherapy, HIFU) and on associated complications (e.g., incontinence, fistula). Primary treatment in most cases represents an endoscopic bilateral incision. No specific advantages of any type of the applied energy (i.e., mono-/bipolar HF current, cold incision, holmium/thulium YAG laser) could be documented. Adjuvant measures such as injection of corticosteroids or mitomycin C have not been helpful in clinical routine. In case of first recurrence, a transurethral monopolar or bipolar resection can usually be performed. Recently, the ablation of the scared tissue using bipolar vaporization has been recommended providing slightly better long-term results. Thereafter, surgical reconstruction is strongly recommended using an open, laparoscopic, or robot-assisted approach. Depending on the extent of the bladder neck sclerosis and the underlying prostate surgery, a Y-V/T-plasty, urethral reanastomosis, or even a radical prostatectomy with new urethravesical anastomosis should be performed. Stent implantation should be reserved for patients who are not suitable for surgery. The final palliative measure is a cystectomy with urinary diversion or a (continent) cystostomy.

Acute myocardial infarction and cardiogenic shock: prognostic impact of cytokines: INF-γ, TNF-α, MIP-1ß, G-CSF, and MCP-1ß.

BACKGROUND: The IABP SHOCK trial was designed as a morbidity-based randomized controlled trial to determine the effect of intraaortic balloon pulsation (IABP) in patients with infarct-related cardiogenic shock (CS). The primary endpoint was the change in the APACHE II score over a 4-day period. The prospective hypothesis was that adding IABP therapy to "standard care" would reduce CS-triggered multiorgan dysfunction syndrome (MODS). The primary endpoint showed no difference between conventionally managed cardiogenic shock patients and those with additional IABP support. In an inflammatory marker substudy, we analyzed the prognostic value of the cytokines interferon-γ (INF-γ), tumor necrosis factor-α (TNF-α), macrophage inflammatory protein-1ß (MIP-1ß), granulocyte-colony stimulating factor (G-CSF), and monocyte chemoattractant protein-1ß (MCP-1ß). We also investigated the influence of IABP support, age, and gender on cytokine levels. DESIGN: The inflammatory marker substudy of the prospective, randomized, controlled, open label IABP SHOCK Trial (ClinicalTrials.gov ID NCT00469248). MATERIALS AND METHODS: A prospective, randomized, single-center study in a 12-bed intensive care unit at a university hospital was performed. A total of 40 consecutive patients were enrolled. The observational period was 96 h. RESULTS: The investigated cytokines showed a significant contribution in the prediction of mortality. Initial (on admission) and maximal cytokine levels during the observational period showed a similar predictive power. Patients with elevated levels of pro- and antiinflammatory cytokines had a higher risk of dying. The maximal level measured over the observation period in the hospital was also suited to identify the survivors. Close correlations between maximal cytokine levels resulted in the choice of only one independent marker (MIP-1ß) into the multivariate model (OR 1.024, 95% CI 1.005-1.043). Initial cytokine levels were also suitable to predict the survivors; the risk of death significantly increases with increasing IFN-γ level (OR 1.119, 95% CI 1.005-1.246). Cytokine levels were not affected by the presence of IABP support. Age (< 75 or > 75 years) and gender did not have a clinically relevant effect on INF-γ, TNF-α, MIP-1ß, G-CSF, and MCP-1 in CS patients. CONCLUSION: The inflammatory response in patients with myocardial infarction complicated by CS, as reflected by the inflammatory markers INF-γ, TNF-α, MIP-1ß, G-CSF, and MCP-1ß, have been shown to be of prognostic value in estimating clinical outcome.

Increased exercise after stable closed fracture fixation does not affect fracture healing in mice.

PURPOSE: The aim of the present study was to evaluate the systemic biological effect of increased exercise on bone repair after stable fracture fixation. METHODS: Two groups of SKH-1h mice were studied. Animals of the first group (n=36) were housed in cages supplied with a running wheel, while mice of the second group (n=37) were housed in standard cages for control. Using a closed femur fracture model, bone repair was analysed by histomorphometry and biomechanical testing at 2 and 5 weeks. At 2 weeks, we additionally evaluated the expression of the proliferation marker PCNA (proliferating cell nuclear antigen) and the angiogenic and osteogenic growth factor VEGF (vascular endothelial growth factor). To standardise the mechanical conditions in the fracture gap, we used an intramedullary compression screw for stable fracture fixation. RESULTS: Each mouse of the exercise group run a mean total distance of 23.5 km after 2 weeks and 104.3 km after 5 weeks. Histomorphometric analysis of the size and tissue composition of the callus could not reveal significant differences between mice undergoing exercise and controls. Accordingly, biomechanical testing showed a comparable torsional stiffness, peak rotation angle, and load at failure of the healing bones in the two groups. The expression of PCNA and VEGF did also not differ between mice of the exercise group and controls. CONCLUSION: We conclude that increased exercise does not affect bone repair after stable fracture fixation.

Identification of dual mTORC1 and mTORC2 inhibitors in melanoma cells: prodigiosin vs. obatoclax.

The PI3K/AKT/mTOR signaling pathway regulates cell proliferation, survival and angiogenesis. The mammalian target of rapamycin (mTOR) is a protein kinase ubiquitously expressed within cells that regulates cell growth and survival by integrating nutrient and hormonal signals. mTOR exists in two complexes, mTORC1 and mTORC2. Hyperactivation of the mTOR protein has been linked to development of cancer, raising mTOR as an attractive target for cancer therapy. Prodigiosin (PG) and obatoclax (OBX), two members of the prodiginines family, are small molecules with anticancer properties which are currently under clinical trials. In the present paper, we demonstrate that mTOR is a molecular target of both prodiginines in melanoma, a highly drug-resistant cancer model. The inhibition of mTORC1 and mTORC2 complexes by PG or OBX resulted in a loss of AKT phosphorylation at S473, preventing its full activation, with no significant effect on T308. The strongest activity inhibition (89%) was induced by PG on mTORC2. Binding assays using Surface Plasmon Resonance (SPR) provide kinetic and affinity data of the interaction of these small molecules with mTOR. In addition, in silico modeling produced a detailed atomic description of the binding modes. These results provide new data to understand the mechanism of action of these molecules, and provide new structural data that will allow the development of more specific mTOR inhibitors for cancer treatment.

Intravital microscopic studies of angiogenesis during bone defect healing in mice calvaria.

PURPOSE: Due to the great availability of specific antibodies, gene-targeted animals and knockout strains, mouse models came into the focus of musculoskeletal research. Herein, we introduce a calvarian defect model in mice that allows the repetitive analysis of blood vessel formation during bone repair by intravital microscopy. METHODS: The right parietal calvaria of 20 adult CD-1 mice were exposed by skin excision. Under continuous irrigation, a circular defect (Ø0.75 mm) was drilled into the calvarium without penetrating the inner cortical shell. A circular glass (Ø12 mm; thickness 0.15 mm) was fixed by two microscrews (M1; length 2mm) to cover the bone defect. Angiogenesis was analysed by intravital microscopy at days 0, 3, 6, 9, 12, 15, 18 and 21. In addition, bone repair was evaluated by histomorphometry at days 3, 6, 9 and 15. Immunohistochemical stainings for the angiogenic growth factor vascular endothelial growth factor (VEGF) and the cell proliferation marker proliferating cell nuclear antigen (PCNA) were performed to assess angiogenic and proliferative activity during healing of the calvarian defect. RESULTS: Histomorphometry showed a typical pattern of intramembranous bone repair. Osseous bridging of the defect was observed at day 9. This was associated with the formation of a neo-periosteum, which covered the new woven bone and contained a dense network of newly formed blood vessels. At day 9, particularly cells of the neo-periosteum showed intense staining for VEGF, whilst PCNA-positive staining was found mainly in osteoblasts. At day 15, the major fraction of fibrous tissue was replaced by bone undergoing extensive remodelling. Intravital microscopy revealed an increase of vascular density between days 3 and 15. Blood vessel diameters showed an increase between days 3 and 9 and a subsequent decrease between days 9 and 21. CONCLUSIONS: The present calvarian defect model provides a powerful tool to evaluate the process of angiogenesis during intramembranous bone repair in mice.

Sirolimus improves early microcirculation, but impairs regeneration after pancreatic ischemia-reperfusion injury.

Ischemia and reperfusion injury remains a relevant problem in clinical pancreas transplantation. We investigated the effect of sirolimus (SRL) in a rodent model of 90-min warm pancreatic ischemia. Four groups were studied: (1) sham surgery and vehicle; (2) sham surgery and SRL; (3) warm ischemia and vehicle; (4) warm ischemia and SRL. SRL (1.5 mg/kg/day) and vehicle were administered intraperitoneally for 3 days prior to surgery until the animals were killed. Microcirculation was assessed immediately after reperfusion by means of intravital fluorescence microscopy. Histopathological injury, apoptosis, proliferation and biochemical parameters were analyzed at 2 h, 1 day and 5 days after surgery. Ninety minutes after ischemia, intravital microscopy revealed an improved functional capillary density (p < 0.05) and reduction of adherent leucocytes (p < 0.01) and platelets (p < 0.05) in the SRL-treated group compared to the vehicle-treated controls. In contrast, on day 5 after ischemia, the pancreatic tissue of SRL-treated animals showed a higher grade of histological injury (p < 0.05) and higher rate of apoptotic cells (p < 0.05) than the vehicle controls. In summary, our data indicate that administration of SRL improves microcirculation at a very early stage, but results in an impairment of the recovery phase after pancreatic ischemia-reperfusion injury.

Disseminated adenovirus infection with respiratory failure in pediatric liver transplant recipients: impact of intravenous cidofovir and inhaled nitric oxide.

Adenoviruses (AdV) are opportunistic pathogens that can lead to severe infections and respiratory failure (acute respiratory distress syndrome, ARDS) with high mortality in immunosuppressed patients. Cidofovir (CDV) has been used in adenoviral disease in bone marrow transplant recipients. Two pediatric liver transplant recipients with disseminated adenoviral disease and ARDS were treated with reduction of immunosuppression, CDV, and inhaled nitric oxide (iNO). CDV 1 mg/kg was given three times per week intravenously with intravenous hydration and oral probenecid. Viral suppression and clinical improvement was achieved. AdV hepatitis did not occur, and graft function was preserved, although acute rejection occurred in both patients. Adverse effects were mild and transient not requiring dose modification. Severe hypoxemia was reversed with iNO 10-20 p.p.m. CDV treatment of AdV infections in organ transplant recipients and other immunocompromised patients should be further investigated in prospective studies.

Fluctuation of the cytokine expression in the liver during the chronic woodchuck hepatitis virus (WHV) infection is not related to viral load.

The woodchuck together with the woodchuck hepatitis virus (WHV) is an excellent model to study the pathogenesis of hepadnaviral infections. Chronic WHV infection causes severe liver disease and hepatocellular carcinoma in woodchucks. The mechanism of viral clearance is not fully understood, interferons seem to play a major role in down-regulating viral replication prior to elimination of infected hepatocytes. We investigated on the pattern of cytokine and T-cell-marker expression in livers of woodchucks chronically infected with WHV. RNase-protection-assay (RPA) was used to determine mRNA of woodchuck specific genes (TNF-alpha, IFN-gamma, IL-15, CD3, CD4, CD8). Serial liver biopsies were performed daily or weekly in eight chronic WHV-carrier woodchucks. Cytokine/T-cell-marker expression differed significantly between the time points up to +/-50% within each woodchuck. The different expression patterns of cytokines or T-cell-markers did not correlate to the (weak) fluctuations in the viremia but may explain the observed fluctuations in the WHV/HBV-load in chronically infected individuals. Furthermore, we observed associations between cytokine and T-cell-marker expression. The marginal fluctuations in viremia during the chronic infection may indicate, that, once the chronic hepadnaviral infection is established, cytokines/interferons expressed endogenously (i.e. not vector-borne or injected) play only a minor role.

An engineered IN-1 F(ab) fragment with improved affinity for the Nogo-A axonal growth inhibitor permits immunochemical detection and shows enhanced neutralizing activity.

The myelin axonal growth inhibitor NI-220/250 (Nogo-A) has attracted considerable attention in elucidating the mechanisms that account for the lack of plasticity in the adult central nervous system. The cognate monoclonal antibody IN-1, which was obtained prior to the molecular characterization of its Nogo-A antigen, has played a crucial role in this respect. However, this murine IgM/kappa antibody does not only provide an inappropriate format for in vivo studies, its low antigen affinity has also hampered the thorough structure-function analysis of its neutralizing effect toward the Nogo-A inhibitor on a molecular basis. We describe here the affinity maturation of a bacterially produced functional IN-1 F(ab) fragment via protein engineering. A soluble fragment of Nogo-A derived from the central exon 3 of its gene, which was prepared by secretion into the periplasm of Escherichia coli, served as a target in these experiments. After repeated cycles of site-directed random mutagenesis and screening, the mutant II.1.8 of the IN-1 F(ab) fragment was obtained, carrying five side chain substitutions within CDR-L3. Its dissociation constant for the complex with the recombinant Nogo-A fragment was determined in surface plasmon resonance measurements as approximately 1 microM. The affinity of the unmutated IN-1 F(ab) fragment was 8-fold lower. The engineered F(ab) fragment appeared to be well suited for the specific detection of Nogo-A in immunochemical assays and for the histochemical staining of myelin-rich tissue sections. Most importantly, its concentration-dependent neutralizing effect on the Nogo-A inhibitory activity was significantly enhanced in cell culture. This study confirms Nogo-A to be the antigen of the IN-1 antibody and it demonstrates increased potential of the engineered F(ab) fragment as a reagent for promoting axonal regeneration in vivo.

Regulation of gap junctional communication by a pro-inflammatory cytokine in cystic fibrosis transmembrane conductance regulator-expressing but not cystic fibrosis airway cells.

Airway inflammation is orchestrated by cell-cell interactions involving soluble mediators and cell adhesion molecules. Alterations in the coordination of the multicellular process of inflammation may play a major role in the chronic lung disease state of cystic fibrosis (CF). The aim of this study was to determine whether direct cell-cell interactions via gap junctional communication is affected during the inflammatory response of the airway epithelium. We have examined the strength of intercellular communication and the activation of nuclear factor-kappaB (NF-kappaB) in normal (non-CF) and CF human airway cell lines stimulated with tumor necrosis factor-alpha (TNF-alpha). TNF-alpha induced maximal translocation of NF-kappaB into the nucleus of non-CF as well as CF airway cells within 20 minutes. In non-CF cells, TNF-alpha progressively decreased the extent of intercellular communication. In contrast, gap junctional communication between CF cells exposed to TNF-alpha remained unaltered. CF results from mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Interestingly, transfer of wild-type CFTR into CF cells by adenovirus-mediated infection was associated with the recovery of TNF-alpha-induced uncoupling. These results suggest that expression of functional CFTR is necessary for regulation of gap junctional communication by TNF-alpha. Gap junction channels close during the inflammatory response, therefore limiting the intercellular diffusion of signaling molecules, and thereby the recruitment of neighboring cells. Defects in this mechanism may contribute to the excessive inflammatory response of CF airway epithelium.

Large nontransplanted hepatocellular carcinoma in woodchucks: treatment with adenovirus-mediated delivery of interleukin 12/B7.1 genes.

BACKGROUND: Cytokine-based gene therapy strategies efficiently stimulate immune responses against many established transplanted tumors, leading to rejection of the tumor. In this study, we investigated the therapeutic potential of cancer immunotherapy in a clinically more relevant model, woodchucks with primary hepatocellular carcinomas induced by woodchuck hepatitis virus. METHODS: Large (2-5 cm), established intrahepatic tumors were given an injection once with 1 x 10(9) plaque-forming units of AdIL-12/B7.1, an adenovirus vector carrying genes for murine interleukin 12 and B7.1, or of AdEGFP, the control virus, and regression of the tumors was then monitored. Five animals were used in total. RESULTS: In four tumor-bearing animals, the antitumor response was assessed by autopsy and histologic analysis within 1-2 weeks after treatment. In all animals treated with AdIL-12/B7.1 therapy versus AdEGFP therapy, we observed substantial tumor regression (P =.006; two-sided unpaired Student's t test) accompanied by a massive infiltration of T lymphocytes. These tumors also contained increased levels of CD4(+) and CD8(+) T cells and interferon gamma (IFN gamma). In continuously growing tumor nodules given an injection of the control virus or in nontumoral liver, no such effects (i.e., tumor regression and increased levels of CD4(+) and CD8(+) T cells and IFN gamma) were detected. In the fifth animal, monitored for long-term antitumor efficacy by magnetic resonance imaging (MRI) after intratumoral vector administration by MRI guidance, the tumor was almost completely eliminated (> or = 95%) 7 weeks after treatment. CONCLUSION: Adenovirus vector-based immunotherapy appears to be an effective treatment of large nontransplanted (orthotopic) tumors that acquire malignant characteristics in a stepwise process, reflecting the real-world scenario of hepatocellular carcinoma in humans.

Thermoregulation: anesthetic and perioperative concerns.

Hypothermia has long been common in anesthesia and has largely been seen as an inconvenience. For many years, it was viewed as inevitable. But hypothermia is much more than an inconvenience, and it is no longer inevitable. Hypothermia is closely associated with significant morbidity both intraoperatively and postoperatively. Hypothermia may begin in the preoperative holding area, so efforts to prevent it should begin there as well. Effective intraoperative and postoperative warming methods are known and commonly available, but they remain underused. Understanding how and why core temperature declines in association with anesthesia and surgery and safe, effective methods to prevent that decline will enable nurse anesthetists and perioperative nurses to increase both the comfort and safety of their patients while reducing costs to the institution.

Human papillomavirus type 16 E7 oncoprotein binds and inactivates growth-inhibitory insulin-like growth factor binding protein 3.

The E7 protein encoded by human papillomavirus type 16 is one of the few viral genes that can immortalize primary human cells and thereby override cellular senescence. While it is generally assumed that this property of E7 depends on its interaction with regulators of the cell cycle, we show here that E7 targets insulin-like growth factor binding protein 3 (IGFBP-3), the product of a p53-inducible gene that is overexpressed in senescent cells. IGFBP-3 can suppress cell proliferation and induce apoptosis; we show here that IGFBP-3-mediated apoptosis is inhibited by E7, which binds to IGFBP-3 and triggers its proteolytic cleavage. Two transformation-deficient mutants of E7 failed to inactivate IGFBP-3, suggesting that inactivation of IGFBP-3 may contribute to cell transformation.

Sesquiterpene lactones are potent inhibitors of interleukin 8 gene expression in cultured human respiratory epithelium.

Sesquiterpene lactones, derived from Mexican-Indian medicinal plants, are known to have potent anti-inflammatory properties but the mechanisms of this effect are not completely understood. Recent data demonstrated that sesquiterpene lactones were potent inhibitors of the pro-inflammatory transcription factor NF-kappaB. Because activation of NF-kappaB is involved in the regulation of the chemokine interleukin 8 (IL-8), we hypothesized that the sesquiterpene lactones, isohelenin and parthenolide, would inhibit IL-8 gene expression in cultured human respiratory epithelium. Incubating A549 cells with tumour necrosis factor alpha (TNF-alpha) induced IL-8 mRNA expression and secretion of immunoreactive IL-8. Pretreatment with either isohelenin or parthenolide inhibited TNF-alpha-mediated IL-8 gene expression in a concentration-dependent manner. Pretreatment with either compound inhibited TNF-alpha mediated activation of the IL-8 promoter and TNF-alpha-mediated nuclear translocation of NF-kappaB. In addition, pretreatment with isohelenin or parthenolide inhibited TNF-alpha-mediated degradation of the NF-kappaB inhibitory protein, I-kappaBalpha. We conclude that sesquiterpene lactones are potent in vitro inhibitors of IL-8 gene expression in cultured human respiratory epithelium. The most proximal mechanism of inhibition appears to involve inhibition of I-kappaBalpha degradation. Stabilization of cytoplasmic I-kappaBalpha leads to inhibition of NF-kappaB nuclear translocation and of subsequent IL-8 promoter activation. The ability of sesquiterpene lactones to modulate IL-8 gene expression may explain, in part, their anti-inflammatory effects.