Screening colonoscopy in HIV-infected patients: high rates of mucosal abnormalities in a German HIV-infected cohort.

OBJECTIVES: Because of the improved life expectancy provided by successful antiretroviral combination therapy, preventive health measures in HIV-infected patients have assumed increasing importance. To date, no data exist on rates of mucosal abnormalities detected by screening colonoscopy in > 50-year-old HIV-infected patients in Germany. The aim of this study was to obtain such data. METHODS: A screening colonoscopy was offered to 159 HIV-infected patients (age > 50 years) who presented for HIV standard of care visits at the infectious diseases out-patient clinic at the university hospital in Bonn over a 1-year period from February 2010. Pearson's χ(2) test, Fisher's exact test and the Mann-Whitney U-test were used for statistical analysis. RESULTS: Fifty-one patients (32.1%) had undergone a screening colonoscopy in the past 10 years, and 45 patients (28.3%) were eventually screened in the observation period. The median age of the 96 screened patients (86% male and 14% female) was 58 years [interquartile range (IQR) 54-64 years]. Overall, endoscopic abnormalities were found in 61% of patients. Histological examination showed tubular adenomas in 21.9% of patients, tubulovillous adenomas in 3.1% and serrated adenomas in 1%. Hyperplastic polyps were found in 15.6% of patients, a nonspecific colitis in 16.7% and diverticulosis in 12.5%. In four cases there was even an early-stage carcinoma (two anal, one rectal and one colon cancer). In univariate analysis, no significant differences with regard to immune status, highly active antiretroviral therapy, family history, personal risk factors or comedication were found between patients with dysplastic and normal mucosas. CONCLUSIONS: The high acceptance rate of screening colonoscopy and the in comparison with the HIV-negative population comparably higher rate of abnormalities in this cohort of HIV-infected patients justify enhanced implementation of screening colonoscopy in clinical practice.

Feasibility and safety of long-term photodynamic therapy (PDT) in the palliative treatment of patients with hilar cholangiocarcinoma.

BACKGROUND AND AIM: PDT is an important palliative option for patients with unresectable extrahepatic cholangiocarcinoma (CC). However, the results published to date reported on studies with no more than 6 (mostly up to 4) PDT procedures. Furthermore, the clinical experience of PDT in combination with chemotherapy is limited. The purpose of this retrospective analysis was to evaluate the feasibility and safety of multiple (4 to 14) settings of PDT, combined with biliary drainage, and (in some cases) with chemotherapy. - METHODS: Ten patients with unresectable extrahepatic CC were treated with biliary stenting and at least 4 PDT procedures in our department between 10/2005 and 08/2010. - RESULTS: Ten patients (male/female = 5/5), mean age 68.8 years (range, 54 - 81 years) who received at least 4 PDT procedures were analyzed. All patients underwent endoscopic biliary drainage. Nine patients received metallic stents and one patient a plastic stent. In 4 patients (40%) bilateral metal stenting (JoStent SelfX®) was performed. The mean number of PDT sessions was 7.9 ± 3.9 (range: 4 - 14). Eight patients had elevated bilirubin levels with a mean bilirubin at admission of 9.9 ± 11.3 mg/dL, which had decreased to an average minimum of 1.2 ± 0.9 mg/dL after 3 months. No severe toxicity was noted. Two patients received concomitant chemotherapy (GEMCIS as 1st line, GEMOX plus cetuximab as 2nd line). The median overall survival has not been reached, whereas the estimated survival of all patients was 47.6 months, 95% CI 25.9 - 48.1. - CONCLUSION: Long-term PDT in patients with extrahepatic CC is feasible and effective and is accompanied - at least in this cohort- by a survival time of more than 2 years.

Inhibition of neuropilin-1 by RNA-interference and its angiostatic potential in the treatment of hepatocellular carcinoma.

Neuropilin-1 (Nrp1) was recently described as a novel receptor for the pro-angiogenic molecule vascular endothelial growth factor (VEGF), indicating a role in tumor angiogenesis and tumor progression. Recent data confirm this assumption by demonstrating that some tumor and endothelial cells express Nrp1. Therefore, we wanted to investigate the potential role of Nrp1-knockdown on hepatoma and endothelial cell function in vitro and tumor growth in vivo. Nrp1 knockdown in SVEC4 - 10 and Hepa129 cells and its influence on signal transduction (MAPK pP38, pAKT, pERK1 / 2) was analyzed by Western blot. Effects on endothelial tube formation were assayed in an in vitro and in vivo matrigel assay. In vivo, effects of siRNA-Nrp1 were analyzed in a subcutaneous hepatoma model. To verify effects on endothelial and tumor cells in vivo, immunohistochemistry for proliferation, apoptosis and endothelial vessels was performed. LightCycler and Western blot analysis showed efficient inhibition of gene expression in SVEC4 - 10 and Hepa129 cells following siRNA-Nrp1 transfection. Signal transduction pathways were not influenced after siRNA-Nrp1 treatment compared to the controls. Endothelial tube formation was reduced by 59 % and 94 % in vitro and in vivo compared to controls, corresponding to reduced VCAM expression. Subcutaneous tumor growth was not influenced after siRNA treatment. Intratumoral proliferation was not altered after treatment with siRNA-Nrp1, whereas microvessel density and apoptosis were reduced after treatment with siRNA-Nrp1 compared to siRNA-Ctrl. In conclusion, inhibition of Nrp1 expression led to strong anti-endothelial effects, whereas tumor cells and tumor growth were not affected.

Course and therapy of acute liver failure.

OBJECTIVES AND METHODS: Despite liver transplantation and advances in intensive care medicine fulminant hepatic failure [FHF] remains a life-threatening condition. Actual observations of the clinical course of these patients are rare. Therefore, we analyzed course of disease and survival in all patients treated for FHF at the University of Bonn between 1998 and 2004 and compared it to the patients treated for FHF during 1992-1997. RESULTS: 35 patients were treated for FHF during this period. FHF was viral induced in 13 patients (HBV n = 11, HAV n = 2), toxic in nine, cryptogenic in eleven and autoimmune and hyperthermia in one patient each. According to London- and/or Clichy criteria 16 patients were transplanted. Four of them died during the first year after transplantation due to infectious and hemorrhagic complications. Three patients died without liver-transplantation. All together, 1-year survival was 80%. When compared to patients with FHF analyzed in the period 1992-1997 numbers of patients with FHF in our centre had increased from 16 to 35 patients and 1-year survival improved from 67.5% to 80%. This improved survival was associated with a lower proportion of transplanted patients (45% versus 68%). CONCLUSIONS: These changes reflect advances in therapy of patients with FHF, which enables a greater proportion of patients to survive without the need for transplantation.

In vivo visualization of early microcirculatory changes following ischemia/reperfusion injury in human kidney transplantation.

To determine whether microcirculatory changes following ischemia/reperfusion (I/R) may serve as predictors for subsequent graft dysfunction, we used noninvasive orthogonal polarization spectral (OPS) imaging to directly visualize and quantify cortical kidney microcirculation. In a total of 13 combined kidney/pancreas recipients, following reperfusion (5/30 min) microcirculatory parameters such as capillary diameter, functional capillary density (FCD) and red-blood-cell velocity (V(RBC)) of the renal graft were analyzed. From these parameters, a heterogeneity index (HI) and volumetric capillary blood flow (vCBF) were calculated. In addition, the extent of graft injury was determined by daily analysis of serum creatinine, blood urea nitrogen, C-reactive protein and systemic leukocyte count for 7 days post-transplant. At early reperfusion, a heterogeneous perfusion pattern with oscillating flow and scattered microvascular thrombosis of peritubular capillaries, resembling a 'no reflow', was observed. FCD was constant throughout the entire reperfusion period, whereas HI, capillary diameters, V(RBC) and vCBF increased. The latter showed a significant positive correlation with creatinine changes between days 1 and 3. So far our finding of a positive correlation of early microvascular changes (vCBF) and clinical parameters (creatinine) indicate a possible therapeutic implication of OPS imaging to predict early I/R-induced renal graft dysfunction.

[Medical therapy of complications in liver cirrhosis]. / Medikamentöse Therapie der Komplikationen der Leberzirrhose.

Patients with liver cirrhosis bear a considerable risk of a variety of complications that involve virtually all organ systems. They can be addressed with a wide spectrum of drugs for acute interventions as well as for prophylactic purposes. At the same time treatment of the underlying disease, the identification and treatment of triggering factors and the possibility of liver transplantation should be kept in mind.

Kininogens coordinate adaptive immunity through the proteolytic release of bradykinin, an endogenous danger signal driving dendritic cell maturation.

Strategically positioned in peripheral tissues, immune sentinel cells sense microbes and/or their shed products through different types of pattern-recognition receptors. Upon secretion, pre-formed pro-inflammatory mediators activate the microvasculature, inducing endothelium/neutrophil adherence and impairing endothelium barrier function. As plasma proteins enter into peripheral tissues, short-lived proinflammatory peptides are rapidly generated by limited proteolysis of complement components and the kininogens (i.e. kinin-precursor proteins). While much emphasis has been placed on the studies of the vascular functions of kinins, their innate effector roles remain virtually unknown. A few years ago, we reported that exogenous bradykinin (BK) potently induces dendritic cell (DC) maturation, driving IL-12-dependent Th1 responses through the activation of G-protein-coupled BK B(2) receptors (B(2)R). The premise that immature DC might sense kinin-releasing pathogens through B(2)R was demonstrated in the subcutaneous mouse model of Trypanosoma cruzi infection. Analysis of the dynamics of parasite-evoked inflammation revealed that activation of TLR2/neutrophils drives the influx of plasma proteins, including kininogens, into peripheral tissues. Once associated to cell surfaces and/or extracellular matrices, the surface-bound kininogens are cleaved by T. cruzi cysteine proteases. Acting as short-lived 'danger' signals, kinins activate DC via B(2)R, converting them into Th1 inducers. Fine tuned control of the extravascular levels of these natural peptide adjuvants is exerted by kinin-degrading metallopeptidases, e.g. Angiotensin converting enzyme (ACE/CD143). In summary, the studies in the subcutaneous model of T. cruzi infection revealed that the peripheral levels of BK, a DC maturation signal, are controlled by TLR2/neutrophils and ACE, respectively characterized as positive and negative modulators of innate/adaptive immunity.

Worsening of long-term myocardial function after successful pharmacological pretreatment with cyclosporine.

Pretreatment with cyclosporine (CsA) decreases infarct size 24h after myocardial ischemia/reperfusion (I/R). The goal of this study was to determine effects of CsA pretreatment on long-term cardiac function after I/R-injury. Rats were randomly assigned to group-1: vehicle-only, group-2: CsA-5mg/kg/day, and group-3: CsA-12.5mg/kg/day given orally for three days prior to I/R-injury (30 min of left anterior descending coronary artery occlusion). Post-I/R survival and cardiac function were evaluated 14 days after I/R-injury by echocardiography and invasive hemodynamic measurements. Rats with I/R-injury showed increased left ventricular pressure (LVEDP) compared to rats without I/R-injury (p<0.005). Although CsA initially decreased infarct size, no differences of LVEDP were seen 14 days after I/R-injury (vehicle: 21.2+/-8.9 mmHg, CsA-5mg/kg/day: 21.5+/-0.7 mmHg, CsA-12.5mg/kg/day: 20.5+/-9.4 mmHg). Ejection fraction and fractional shortening were decreased compared to baseline, but showed no differences between groups. On day 14, a dose-dependent increase in left ventricular end diastolic diameter was seen (p<0.001). CsA pretreatment was associated with a dose-dependent decrease in post-I/R-survival (vehicle: 56%, CsA-5mg/kg/day: 32%, CsA-12.5mg/kg/day: 16%; p=0.017). CsA pretreatment did not improve long-term cardiac function despite decreased infarct size 24h after I/R-injury, but increased post-I/R mortality significantly. Poor cardiac function after CsA pretreatment might be caused by left ventricular dilation.

Increased VEGF levels induced by anti-VEGF treatment are independent of tumor burden in colorectal carcinomas in mice.

Inhibition of vascular endothelial growth factor (VEGF) by gene transfer techniques was effectively applied to control experimental tumor growth, whereas effects on systemic VEGF levels had not been investigated. Therefore, we evaluated the effect of VEGF inhibition by adenoviral-mediated gene delivery of a dominant-negative soluble fragment of FLK-1 (sFlk-1) on systemic VEGF levels, organ-specific VEGF-RNA expression and antitumor efficacy in a murine colorectal cancer (CRC) tumor model. Vector function of AdsFlk-1 was shown by Western blot analysis and transgene expression was documented over a time period of 42 days in the serum of treated mice. Although cell supernatant of CT26 cells contained considerable levels of VEGF, systemic VEGF levels in the serum of tumor-bearing mice remained unaffected. Interestingly, mice that were systemically treated with AdsFlk-1 showed a strong upraise of circulating VEGF, whereas VEGF remained at background levels in the control. Vascular endothelial growth factor was increased not only in tumor bearing but also in healthy, tumor-free mice. Vascular endothelial growth factor determination in liver tissue homogenates showed a 16.5-fold upraise in AdsFlk-1-treated animals as compared to the AdLacZ control. Consecutively, systemic small interfering RNA injection targeted against VEGF reverted elevated VEGF levels almost back to normal levels. In spite of elevated VEGF levels, AdsFlk-1 administration showed significant antitumor effects in a subcutaneous metastatic CRC tumor model. There was no significant correlation between antitumour treatment response and VEGF levels in this model. Collectively, we conclude that the systemic administration of AdsFlk-1 had significant inhibitory effects on metastatic CRC tumor growth in spite of elevated systemic VEGF levels and that VEGF serum concentrations did not correlate to tumor burden and antitumor treatment response in this model.

[Secondary cancers in childhood]. / Faut-il craindre l'apparition d'un second cancer en pédiatrie?

Improved survival of pediatric cancer patients will lead to an increase of late sequellae such as secondary malignant neoplasms (SMN). Specific pediatric factors predisposing to these SMN are as follows: long expecting duration of life, high cellular proliferative potential, toxicity of often combined cancer therapies (radio- and chemotherapies) and more frequent genetic predisposition to cancer. Better understanding of these factors could improve patients management and could lead to the development of less toxic future therapies with the hope to decrease the risk of SMN.

Surgical complications and long-term outcome of different biliary reconstructions in liver transplantation for primary sclerosing cholangitis-choledochoduodenostomy versus choledochojejunostomy.

Choledochojejunostomy (CJS) is commonly used for biliary reconstruction in liver transplantation for primary sclerosing cholangitis (PSC). We alternatively performed choledochoduodenostomy (CDS) and side-to-side choledochodocholedochstomy in a large cohort of patients. Fifty-one patients with PSC, transplanted between 1988 and 2000, were analyzed retrospectively. Biliary reconstruction was CDS in 25 (49%), CJS in 20 (39%) and CC in 6 transplantations (12%). Biliary leaks occurred in the early follow-up (< or =41 days) only in CDS patients (20%). However, in the late follow-up (>4 months), stricturing of anastomosis was found once in CDS (4%) and CJS (5%). Later (>9 months), intrahepatic bile duct strictures were diagnosed in four CDS (16%), one CJS (5%) and one CC (17%) patient(s). In 48% of CDS (12/25), 60% of CJS (12/20) and 17% of CC (1/6) at least one incidence of cholangitis was observed. Overall, biliary complication rates were significantly higher in CDS (40%) than CJS (10%) and CC (17%); of those none in CC and 12% in CDS were anastomosis-related. Graft/patient survival showed no significant differences among groups. Based on our results we consider CJS the standard method for biliary reconstruction in PSC; however, in selected cases where CJS is difficult to accomplish because of previous surgery or for retransplantation, CDS may present an alternative technique.

[Clinical evaluation of 23 children with neuroblastoma. The experience of a single institution]. / Les neuroblastomes de l'enfant. A propos de 23 cas.

In this retrospective study, we analyse epidemiology, clinical symptoms and therapeutic results in a group of 23 children with neuroblastoma. Half of them were less than 2 years of age; in 19 of 23, the primitive tumour was abdominal; 35% of them were initially metastatic. The overall survival was 83% at 5 years and the event free survival, 75% at 5 years. Pronostic factors are age, extension of the disease at diagnosis, biologic parameters and genetic study of the neuroblast cells (amplification of N-myc oncogen). Our study shows the deleterious effect of bone lesions.

[Acute lymphoblastic leukemia in children]. / Quel espoir pour les LLA de l'enfant? Bilan du CHR de la Citadelle.

We report our experience over the last seventeen years (1985-2002) of the treatment of acute lymphoblastic leukemia (ALL) in children at the University of Liege Pediatric Department of Hematogy-Oncology (CHU-Sart Tilman and CHR-Citadelle). Seventy seven children are enrolled in our study; the mean follow-up is 6.7 years. The 5 years over all survival and the disease free survival for the entire group are respectively 83% and 79%. Prognostic factors shown in our study are sex, high white blood cells counts at diagnosis and immunophenotypes.

[Retrospective study of childhood lymphomas. Report of 27 children treated at a single institution]. / Etude rétrospective des lymphomes de l'enfant. A propos de 27 cas traités dans une même institution.

Childhood lymphomas represent a heterogeneous group of disorders that are quite different from adult lymphomas. Over the past three decades, empirical chemotherapeutic management has transformed survival figures, and more recently greater understanding of the biology is offering hope for improved management of resistant disease. We present here the experience of a single institution in the management of 27 childhood lymphomas; epidemiological and clinical characteristics are described as well as survival rates. The median follow up of the patients is 4 years 7 months. The five-year overall survival for the entire group is more than 95 %; the 5-year disease free survival is 91,6 % for Hodgkin's lymphomas, 92,8% for non Hodgkin's lymphomas and 100% for Burkitt diseases. Two relapses have occurred and all of them appeared within the 18 months of the diagnosis. No toxic death has been reported.

[Vaccinations in HIV-infected children]. / Vaccins classiques et moins classiques chez l'enfant infecté par le VIH.

The increased vulnerability of HIV infected children to infections supports the principle of vaccination. This article summarizes the available data on the practice of vaccination among HIV infected children. Vaccination is, in general, harmless and efficacious in those children. The World Health Organisation (WHO) guidelines are very similar to other recommandations. Nevertheless, the HIV related immunosuppression reduces the vaccination benefits. Moreover, serious complications are possible after BCG-vaccine administration in seriously immunocompromised children. Therefore, children with AIDS should not be given this vaccine. The benefits of anti-poliomyelitis and anti-measles vaccination markedly exceed the low post-vaccination risk reported among these children.

[Infections and antibiotic prophylaxis in sickle cell disease]. / Infections et prophylaxies antiinfectieuses dans la drépanocytose.

Bacterial infections remain a major cause of morbidity and mortality among young children with sickle cell disease. Susceptibility to infections is mainly observed in homozygous sickle cell disease. The incidence of bacteremias in children under 3 years of age is approximately 8 events/100 patient-years among homozygous subjects and approximately S events/100 patient-years among those with SC hemoglobinopathy. Pneumococci and Salmonellae are the most frequently isolated bacteria. Severe clinical manifestations include septicemia, meningitis, osteomyelitis and pneumonia. M. Pneumoniae and C. Pneumoniae infections may be severe and may induce acute chest syndrome. The high incidence and severity of bacterial infections in these children justify prevention efforts by antibiotic prophylaxis and vaccination. The efficacy of oral penicillin prophylaxis against pneumococcal infections has been well demonstrated and is now recommended from 3 months of age. The antipneumococcal conjugate vaccine has been shown to be safe and immunogenic in young infants.

Calculation of high frequency ultrasonic signals for shear wave insonification in solid material.

The goal of the theoretical part is to simulate an automatic ultrasonic inspection with contact technique shear wave probes, where the high frequency signals are captured and used to perform a reconstruction based on the synthetic aperture focusing method "SAFT". Therefore the ultrasonic probe, the scanning path and the defects are parameters in a CAD model. The scattering behavior of the defect is calculated by the Kirchhoff approximation in its elastodynamic version. The result of the simulation--the high frequency data--and the result of the SAFT-reconstructions are compared with experimental results on a steel test block with side drilled and flat bottom holes. The model is validated by the experiment. One of the applications of the model is to identify multiple reflections.

Treatment of colorectal and hepatocellular carcinomas by adenoviral mediated gene transfer of endostatin and angiostatin-like molecule in mice.

AIM AND METHOD: In this study, we explored the responsiveness of different tumour entities (colorectal carcinoma (CRC), hepatocellular carcinoma (HCC), and the murine Lewis lung carcinoma (LLC)) to angiostatic antitumour treatment with two recombinant adenoviral vectors encoding angiostatin-like molecule (AdK1-3) and endostatin (Adendo). RESULTS: AdK1-3 and Adendo exerted inhibitory biological functions on endothelial cell proliferation, migration, and tube formation in vitro. AdK1-3 inhibited significantly endothelial cell infiltration in vascular endothelial growth factor embedded Matrigel plugs in mice whereas Adendo showed only minor effects. Both AdK1-3 and Adendo induced similar antitumour effects in the LLC tumour model in immune competent C57BL/6 mice but AdK1-3 had stronger inhibitory effects in athymic mice. Furthermore, AdK1-3 inhibited tumour growth in a murine CRC and human HCC model but was ineffective in a human CRC model. In contrast, Adendo did not reduce tumour progress in either of these tumour models although AdK1-3 and Adendo effectively reduced intratumoral microvessel density in LLC tumours. CONCLUSION: Our data demonstrate that angiostatic gene therapy may form a feasible strategy for the treatment of established hepatocellular carcinomas and that in vivo antitumour efficacy of angiostatic proteins is tumour specific.

A novel strategy for the generation of angiostatic kringle regions from a precursor derived from plasminogen.

In this study we have explored the feasibility of generating angiostatin by incorporating an endoproteolytic furin cleavage site into plasminogen to allow conversion of the precursor molecule into an angiostatic active K1-3 fragment. We show that secretable angiostatin can be successfully generated from cells infected with adenovirus carrying the furin-mutated plasminogen (AdmuthPlgK3). Supernatant from cells transduced with AdmuthPlagK3 inhibits tube formation and proliferation and migration of human umbilical vein endothelial cells with an efficiency similar to that of supernatant from cells infected with adenovirus expressing kringle 1-3 of plasminogen (AdK1-3). Administration of AdmuthPlgK3 and AdK1-3 in mice results in significantly decreased endothelial cell infiltration in VEGF-embedded Matrigel plugs. Treatment with AdmuthPlgK3 and AdK1-3 exerts strong antitumoral effect in models of hepatocellular carcinoma and Lewis lung cancer. This antitumor effect was associated with decreased microvessel density in the tumors. Taken together, our data demonstrate that angiostatin endowed with strong antiangiogenic and antitumor effects can be released from a furin-mutated plasminogen acting as a precursor. This strategy may have potential to develop angiostatic anti-cancer therapies.