[Uveal Melanoma Cell Under Oxidative Stress - Influence of VEGF and VEGF-Inhibitors]

BACKGROUND

The role of oxidative stress in cancer is complex. While the pathological alterations induced by oxidative stress may be involved in the induction of tumours, in the late stages of tumour development, it can facilitate the loss of tumour cells and might even prevent metastasis. Tumour cells show metabolic alterations, often inducing an increased production of reactive oxygen species, which makes these cells particularly vulnerable to additional oxidative stress. This is an important mode of action in the use of many chemotherapeutics and in the application of ionizing radiation. Uveal melanoma is the most frequent primary tumour in the adult eye. For metastasis of this tumour, which affects about 50 % of the patients, no appropriate treatment is currently available. However, the primary tumour can efficiently be treated with ionizing radiation. A frequent side effect of this treatment is radiation retinopathy, which is treated with vascular endothelial growth factor (VEGF) antagonists. A therapy of the primary tumour with VEGF antagonists is under discussion. So far, little data is available on this subject, however, a paradoxical worsening of the situation has been found in a mouse model of uveal melanoma treated with bevacizumab.

METHODS

We have investigated the effect of VEGF and of the VEGF-antagonist bevacizumab on the survival of five different melanoma cell lines under oxidative stress treatment with hydrogen peroxide. In addition, we investigated the expression of relevant proteins and the effect of bevacizumab on the proliferation of the cells as well as its effect on the angiogenic behaviour of endothelial cells, co-cultured with uveal melanoma cells.

RESULTS

Our study showed that not only VEGF but also, paradoxically, the VEGF-antagonist bevacizumab is able to protect uveal melanoma cells from oxidative stress-induced cell death. Bevacizumab did not influence the proliferation of the cells and showed only limited effectiveness to reduce angiogenic structures.

CONCLUSION

Considering that oxidative stress is the mode of action for ionizing radiation to induce cell death, a protective effect of bevacizumab on uveal melanoma cells against oxidative stress is worrisome and argues against the use of VEGF in uveal melanoma.

Secondary diamines as a monomer from bis-hydroaminomethylation of industrial cyclic dienes

Acetic acid gives amines wings: bis-hydroaminomethylation of dienes to provide industrial secondary diamine monomers. Application of reactive extraction as a recycling method for the rhodium catalyst.

Cerebrospinal fluid lipocalin 2 in patients with clinically isolated syndromes and early multiple sclerosis

Background:

Lipocalin 2 (LCN2) may be involved in the immunopathogenesis of multiple sclerosis (MS) and might further impact on iron homoeostasis. Brain iron accumulates in MS; however, the association to iron-related proteins is still unsolved.

Objective:

To investigate cerebrospinal fluid (CSF) and serum LCN2, transferrin (Trf) and ferritin in early MS in relation to disease evolution and longitudinal brain iron accumulation.

Methods:

We analysed CSF and serum LCN2 by enzyme-linked immunosorbent assay (ELISA) and Trf and ferritin by nephelometry in 55 patients (45 clinically isolated syndrome (CIS), 10 MS, median clinical follow-up 4.8 years) and 63 controls. In patients, we assessed sub-cortical grey matter iron by 3T magnetic resonance imaging (MRI) R2* relaxometry (median imaging follow-up 2.2 years).

Results:

Compared to controls serum ( p < 0.01), CSF ( p < 0.001) LCN2 and CSF Trf ( p < 0.001) levels were reduced in the patients. CSF LCN2 correlated with CSF Trf ( r = 0.5, p < 0.001). In clinically stable patients, CSF LCN2 levels correlated with basal ganglia iron accumulation ( r = 0.5, p < 0.05). In CIS, higher CSF LCN2 levels were associated with conversion to clinically definite MS ( p < 0.05).

Conclusion:

We demonstrate altered LCN2 regulation in early MS and provide first evidence for this to be possibly linked to both clinical MS activity and iron accumulation in the basal ganglia.

Debris-flow risk analysis in a managed torrent based on a stochastic life-cycle performance

Two key factors can affect the functional ability of protection structures in mountains torrents, namely (i) infrastructure maintenance of existing infrastructures (as a majority of existing works is in the second half of their life cycle), and (ii) changes in debris-flow activity as a result of ongoing and expected future climatic changes. Here, we explore the applicability of a stochastic life-cycle performance to assess debris-flow risk in the heavily managed Wartschenbach torrent (Lienz region, Austria) and to quantify associated, expected economic losses. We do so by considering maintenance costs to restore infrastructure in the aftermath of debris-flow events as well as by assessing the probability of check dam failure (e.g., as a result of overload). Our analysis comprises two different management strategies as well as three scenarios defining future changes in debris-flow activity resulting from climatic changes. At the study site, an average debris-flow frequency of 21 events per decade was observed for the period 1950-2000; activity at the site is projected to change by +38% to -33%, according to the climate scenario used. Comparison of the different management alternatives suggests that the current mitigation strategy will allow to reduce expected damage to infrastructure and population almost fully (89%). However, to guarantee a comparable level of safety, maintenance costs is expected to increase by 57-63%, with an increase of maintenance costs by ca. 50% for each intervention. Our analysis therefore also highlights the importance of taking maintenance costs into account for risk assessments realized in managed torrent systems, as they result both from progressive and event-related deteriorations. We conclude that the stochastic life-cycle performance adopted in this study represents indeed an integrated approach to assess the long-term effects and costs of prevention structures in managed torrents.

Radiation dose reduction in CT with adaptive statistical iterative reconstruction (ASIR) for patients with bronchial carcinoma and intrapulmonary metastases

AIM

To compare the radiation dose and image quality of 64-row chest computed tomography (CT) in patients with bronchial carcinoma or intrapulmonary metastases using full-dose CT reconstructed with filtered back projection (FBP) at baseline and reduced dose with 40% adaptive statistical iterative reconstruction (ASIR) at follow-up.

MATERIALS AND METHODS

The chest CT images of patients who underwent FBP and ASIR studies were reviewed. Dose-length products (DLP), effective dose, and size-specific dose estimates (SSDEs) were obtained. Image quality was analysed quantitatively by signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurement. In addition, image quality was assessed by two blinded radiologists evaluating images for noise, contrast, artefacts, visibility of small structures, and diagnostic acceptability using a five-point scale.

RESULTS

The ASIR studies showed 36% reduction in effective dose compared with the FBP studies. The qualitative and quantitative image quality was good to excellent in both protocols, without significant differences. There were also no significant differences for SNR except for the SNR of lung surrounding the tumour (FBP: 35±17, ASIR: 39±22).

DISCUSSION

A protocol with 40% ASIR can provide approximately 36% dose reduction in chest CT of patients with bronchial carcinoma or intrapulmonary metastases while maintaining excellent image quality.

Nanoparticulate CpG immunotherapy in RAO-affected horses: phase I and IIa study

Background

Recurrent airway obstruction (RAO), an asthma‐like disease, is 1 of the most common allergic diseases in horses in the northern hemisphere. Hypersensitivity reactions to environmental antigens cause an allergic inflammatory response in the equine airways. Cytosine‐phosphate‐guanosine‐oligodeoxynucleotides (CpG‐ODN) are known to direct the immune system toward a Th1‐pathway, and away from the pro‐allergic Th2‐line (Th2/Th1‐shift). Gelatin nanoparticles (GNPs) are biocompatible and biodegradable immunological inert drug delivery systems that protect CpG‐ODN against nuclease degeneration. Preliminary studies on the inhalation of GNP‐bound CpG‐ODN in RAO‐affected horses have shown promising results.

Objectives

The aim of this study was to evaluate the clinical and immunological effects of GNP‐bound CpG‐ODN in a double‐blinded, placebo‐controlled, prospective, randomized clinical trial and to verify a sustained effect post‐treatment.

Animals and Methods

Twenty‐four RAO‐affected horses received 1 inhalation every 2 days for 5 consecutive administrations. Horses were examined for clinical, endoscopic, cytological, and blood biochemical variables before the inhalation regimen (I), immediately afterwards (II), and 4 weeks post‐treatment (III).

Results

At time points I and II, administration of treatment rather than placebo corresponded to a statistically significant decrease in respiratory effort, nasal discharge, tracheal secretion, and viscosity, AaDO₂ and neutrophil percentage, and an increase in arterial oxygen pressure.

Conclusion and Clinical Importance

Administration of a GNP‐bound CpG‐ODN formulation caused a potent and persistent effect on allergic and inflammatory‐induced clinical variables in RAO‐affected horses. This treatment, therefore, provides an innovative, promising, and well‐tolerated strategy beyond conventional symptomatic long‐term therapy and could serve as a model for asthma treatment in humans.

Safety of PEGylated recombinant human full-length coagulation factor VIII (BAX 855) in the overall context of PEG and PEG conjugates

Introduction

BAX 855 is a PEGylated human full‐length recombinant factor VIII (rFVIII) based on licensed rFVIII (ADVATE). The applied PEGylation technology has been optimized to retain functionality of the FVIII molecule, improve its pharmacokinetic properties and allow less frequent injections while maintaining efficacy.

Aim

The aim of this study was to confirm that the excellent safety profile of ADVATE remains unchanged after PEGylation.

Methods

Non‐clinical safety studies with BAX 855 and its respective unbound polyethylene glycol (PEG) were conducted in several species. The distribution of a single dose of radiolabelled BAX 855 was further investigated in rats. Publically available safety data on PEG alone and PEGylated biomolecules were summarized and reviewed for specific safety findings attributable to PEG or PEGylated biopharmaceuticals.

Results

Safety pharmacology studies in rabbits and macaques and repeated dose toxicity studies in rats and macaques identified no safety issues. Results of a distribution study in rats administered radiolabelled BAX 855 showed that radioactivity was completely excreted; urine was the major elimination route. A 28‐day study in rats dosed with the unbound PEG constituent (PEG2ru20KCOOH) of BAX 855 showed no adverse or non‐adverse effects.

Safety data for PEG and PEG‐protein conjugates indicate no safety concerns associated with PEG at clinically relevant dose levels. Although vacuolation of certain cell types has been reported in mammals, no such vacuolation was observed with BAX 855 or with the unbound PEG constituent.

Conclusion

Non‐clinical safety evaluation of PEG and BAX 855 identified no safety signals; the compound is now in clinical development for the treatment of patients with haemophilia A.

Combined analysis of global and compartmental brain volume changes in early multiple sclerosis in clinical practice

Background:

The extent and clinical significance of brain volume changes in different phases of multiple sclerosis (MS) is still under discussion.

Objective:

To determine the rate of global and compartmental brain volume changes in patients with a clinically-isolated syndrome (CIS) compared to patients with definite MS, by long-term follow-up and as a predictor of conversion to MS in a routine clinical setting.

Methods:

We investigated 120 patients (63 CIS and 57 MS) at baseline and after a mean follow-up period of 43 months, including detailed clinical examination and 3-Tesla magnetic resonance imaging (MRI). Our imaging analyses comprised the normalized brain volume (NBV), cortical grey matter (cGMV) and white matter (WMV) volumes using SIENA/X, the percentage of brain volume change (PBVC) using SIENA and the change in the volume of the thalami (TV) and basal ganglia (BGV). We also determined the amount and change of T2-lesion load (T2-LL).

Results:

At baseline, all the brain volume metrics, except cGMV, were significantly lower; and the T2-LL was significantly higher, in patients with MS rather than CIS. During the follow-up, only the PBVC was higher in MS ( p = 0.008) and this difference was driven by converters from CIS to MS. Quartiles of PBVC did not allow us to predict conversion to MS, but were associated with the degree of disability.

Conclusions:

PBVC is the most sensitive marker of progressing atrophy and a higher PBVC was generally associated with more active disease; however, it did not serve to predict the course of MS on an individual basis, in this study.

Vascular endothelial growth factor (VEGF) levels in short, GH treated children: a distinct pattern of VEGF-C in Noonan syndrome

CONTEXT

Noonan syndrome (NS) is characterized by short stature and elevated risk of lymphedema. The mechanism underlying lymphedema may be mediated by vascular endothelial growth factors (VEGFs).

OBJECTIVE

To assess the effect of growth hormone (GH) treatment on plasma insulin-like growth factor (IGF)-1, VEGF-A and VEGF-C levels in patients with NS as compared to short GH-sufficient children.

DESIGN

Retrospective, comparative.

SETTING

Endocrinology department of a tertiary pediatric medical center.

PATIENTS AND METHODS

Plasma IGF-1, VEGF-A and VEGF-C levels were measured before and during GH treatment in 6 patients with NS and 18 age-matched short subjects (Turner, idiopathic short stature and small for gestational age).

MAIN OUTCOME MEASURES

Changes in plasma VEGF and IGF-1 levels.

RESULTS

Baseline IGF-1 SDS levels were slightly lower in NS patients compared with controls; IGF-1 response to GH therapy was markedly lower in NS patients compared with controls (p = 0.017). Mean baseline VEGF-A levels were similar in NS patients and controls whilst mean baseline VEGF-C levels were significantly lower in the NS group as compared with controls (p = 0.022). Plasma VEGF-A and VEGF-C levels did not significantly change during GH treatment in the study cohort. No correlation was found between VEGF-C levels and levels of IGF-1, VEGF-A and auxological parameters, either before or during GH administration.

CONCLUSION

Children with NS have a distinct growth factor profile including low basal VEGF-C and flattened IGF-1 response to GH. Further studies are needed to confirm our findings and to elucidate the interaction between VEGF-C levels and lymphedema.

Conversion from clinically isolated syndrome to multiple sclerosis: A large multicentre study

Background and objective:

We explored which clinical and biochemical variables predict conversion from clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (CDMS) in a large international cohort.

Methods:

Thirty-three centres provided serum samples from 1047 CIS cases with at least two years’ follow-up. Age, sex, clinical presentation, T2-hyperintense lesions, cerebrospinal fluid (CSF) oligoclonal bands (OCBs), CSF IgG index, CSF cell count, serum 25-hydroxyvitamin D3 (25-OH-D), cotinine and IgG titres against Epstein-Barr nuclear antigen 1 (EBNA-1) and cytomegalovirus were tested for association with risk of CDMS.

Results:

At median follow-up of 4.31 years, 623 CIS cases converted to CDMS. Predictors of conversion in multivariable analyses were OCB (HR = 2.18, 95% CI = 1.71–2.77, p < 0.001), number of T2 lesions (two to nine lesions vs 0/1 lesions: HR = 1.97, 95% CI = 1.52–2.55, p < 0.001; >9 lesions vs 0/1 lesions: HR = 2.74, 95% CI = 2.04–3.68, p < 0.001) and age at CIS (HR per year inversely increase = 0.98, 95% CI = 0.98–0.99, p < 0.001). Lower 25-OH-D levels were associated with CDMS in univariable analysis, but this was attenuated in the multivariable model. OCB positivity was associated with higher EBNA-1 IgG titres.

Conclusions:

We validated MRI lesion load, OCB and age at CIS as the strongest independent predictors of conversion to CDMS in this multicentre setting. A role for vitamin D is suggested but requires further investigation.

DFT study of Raman spectra of hexakis(4-N'(-di(4-oxyphenethylamino)-(thio)phosphonyl)-N'-methyl-diazobenzene)cyclotriphosphazene

The FT-Raman spectrum of the hexakis(4-N'(-di(4-oxyphenethylamino)-(thio)phosphonyl)-N'-methyl-diazobenzene)cyclotriphosphazene which is the first generation dendrimer G1 built from the cyclotriphosphazene core, six arms -O-C6H4-CH=N-N(CH3)-P(S)< and twelve 4-oxyphenethylamino terminal groups -O-C6H4-(CH2)2-NH2 G1 has been recorded. The structural optimization and normal mode analysis were performed for model compound C, consisting of cyclotriphosphazene core, one arm -O-C6H4-CH=N-N(CH3)-P(S)< and two 4-oxyphenethylamino terminal groups -O-C6H4-(CH2)2-NH2 on the basis of the density functional theory (DFT) at the PBE/TZ2P level. The calculated geometrical parameters and harmonic vibrational frequencies are predicted in good agreement with the experimental data. It was found that G1 has a concave lens structure with planar -O-C6H4-CH=N-N(CH3)-P(S)< fragments and slightly non-planar cyclotriphosphazene core. The 4-oxyphenethylamino groups attached to different arms show significant deviations from a symmetrical arrangement relative to the local planes of repeating units. The experimental Raman spectra of G1 dendron was interpreted by means of potential energy distribution. Relying on DFT calculations, as well as on experimental information, a spectral interpretation was proposed.

Massenspektrometrische Fragmentierung von Trimethylsilylderivaten (TMS) des Thyrotropin-„Releasing“-Hormons (TRH) und dessen Teilstrukturen / Mass Spectroscopy of Trimethylsilyl Derivatives of Thyrotropin-releasing Hormone and its Constituents

The mass spectral fragmentation patterns of trimethylsilyl derivatives of TRH and its constituents are discussed. The utility of these derivatives for the control of the synthesis of peptide hormones by mass spectrometry is obvious.

Cerebrospinal fluid transferrin levels are reduced in patients with early multiple sclerosis

BACKGROUND

Previous magnetic resonance imaging (MRI) studies have demonstrated increased iron deposition in the basal ganglia of multiple sclerosis (MS) patients. However, it is not clear whether these alterations are associated with changes of iron metabolism in body fluids.

OBJECTIVES

The purpose of this study was to investigate if iron metabolism markers in cerebrospinal fluid (CSF) and serum of clinically isolated syndrome (CIS) and MS patients differ from controls and how they relate to clinical and imaging parameters.

METHODS

We analysed serum ferritin, transferrin and soluble transferrin-receptor and CSF ferritin and transferrin by nephelometry in non-anaemic CIS (n=60) or early MS (n=14) patients and 68 controls. In CIS/MS we additionally assessed the T2 lesion load.

RESULTS

CSF transferrin was significantly decreased in CIS/MS compared to controls (p<0.001), while no significant differences were seen in serum. Higher CSF transferrin levels correlated with lower physical disability scores (r= -0.3, p<0.05). CSF transferrin levels did not correlate with other clinical data and the T2 lesion load.

CONCLUSION

Our biochemical study provides evidence that altered iron homeostasis within the brain occurs in the very early phases of the disease, and suggests that the transporter protein transferrin may play a role in the increased iron deposition known to occur in the brain of MS patients.