Broadly tunable laser based on novel metallic resonant leaky-mode diffraction grating.

We present a fibre laser broadly tunable in a wavelength range from 1058 nm to 1640 nm based on a new type of metallic resonant leaky-mode diffraction grating and three fibre-pigtailed semiconductor optical amplifiers. For TM polarization in Littrow configuration, the grating has experimentally measured diffraction efficiency into the -1st reflected order of more than 90 % over a spectral range of 1417 nm to 1700 nm. The laser covered a spectral range of 331 nm within a tuning band of 558 nm without any adjustment of optics and its tuning range was limited by amplification bands of available semiconductor optical amplifiers.

KRAS pathway expression changes in pancreatic cancer models by conventional and experimental taxanes.

The KRAS signalling pathway is pivotal for pancreatic ductal adenocarcinoma (PDAC) development. After the failure of most conventional cytotoxic and targeted therapeutics tested so far, the combination of taxane nab-paclitaxel (Abraxane) with gemcitabine recently demonstrated promising improvements in the survival of PDAC patients. This study aimed to explore interactions of conventional paclitaxel and experimental taxane SB-T-1216 with the KRAS signalling pathway expression in in vivo and in vitro PDAC models in order to decipher potential predictive biomarkers or targets for future individualised therapy. Mouse PDAC PaCa-44 xenograft model was used for evaluation of changes in transcript and protein levels of the KRAS signalling pathway caused by administration of experimental taxane SB-T-1216 in vivo. Subsequently, KRAS wild-type (BxPc-3) and mutated (MiaPaCa-2 and PaCa-44) cell line models were treated with paclitaxel to verify dysregulation of the KRAS signalling pathway gene expression profile in vitro and investigate the role of KRAS mutation status. By comparing the gene expression profiles, this study observed for the first time that in vitro cell models differ in the basal transcriptional profile of the KRAS signalling pathway, but there were no differences between KRAS mutated and wild-type cells in sensitivity to taxanes. Generally, the taxane administration caused a downregulation of the KRAS signalling pathway both in vitro and in vivo, but this effect was not dependent on the KRAS mutation status. In conclusion, putative biomarkers for prediction of taxane activity or targets for stimulation of taxane anticancer effects were not discovered by the KRAS signalling pathway profiling in various PDAC models.

Primary retroperitoneal Ewings sarcoma.

The Ewings sarcoma (EWS) family tumors are small, round, cell tumors with different degrees of neuroectodermal differentiation with a peak incidence in children and young adults. About 10-20% of cases are extraskeletal EWS.

Fatting parameters after duck egg exposure to γ-radiation.

In our experiment, we deal with the phenomenon of radiation hormesis and improvements based on this phenomenon to different growing characteristics of the fast-growing, very feed-efficient, and with a high-yielding carcass hybrid of the Peking duck (Cherry Valley SM3 medium). In the first phase of the project, we exposed hatching duck eggs to low and middle doses of gamma radiation 60Co (0.06-2.00 Gy) before placing them into a setter in the hatchery. We then followed the standards of artificial incubation. The treatment of our chosen doses of gamma radiation has no significant influence on the history and results of hatching (from 85.5% to 92.6%); it was influenced only by the basic management and husbandry of the parent stock. From our observations we confirm that the Peking duck, despite genetic progress, retained its vitality and robustness. Its embryos are not damaged even with a dose of 2 Gy, which is over the deterministic effect of ionizing radiation for vertebrates. At the end of the fatting period a significant drop in plasma phosphorus levels was measured in the ducks; however, it was dependent on the radiation dose to which the hatching eggs were exposed (r = -0.965). A positive effect of radiation hormesis may be expected in the case of 1 Gy dose where the highest values of mean corpuscular hemoglobin, mean corpuscular hemoglobin, combined hemoglobin, and drake weight were measured. Lower and higher doses of ionizing radiation used did not display these effects.

Precise determination of primary cytogenetic abnormalities provides added value for stratification of chronic lymphocytic leukemia patients.

Cytogenetic analysis has become a standard procedure in the management of newly diagnosed chronic lymphocytic leukemia patients. Prognostic information is reported based on the presence of certain abnormalities and karyotype complexity after conventional karyotyping and/or fluorescence in situ hybridization (FISH). The information on cytogenetic abnormalities occurring in isolation is robust; however, the performance of patients with two or more cytogenetic abnormalities is heterogeneous and information is scarce. This retrospective study analyzed whether information on the precise determination of primary cytogenetic abnormalities can have some added value in terms of risk stratification in chronic lymphocytic leukemia (CLL) patients. The study cohort was 121 patients without the need to start treatment for CLL immediately after diagnosis but had completed initial cytogenetic analysis. Results from conventional karyotyping after stimulation of CLL cells and FISH analysis were combined. Risk stratification based purely on the determination of primary cytogenetic abnormalities was effective in CLL patients, with comparable results in stratification based on the presence of certain abnormalities and karyotype complexity. It is recommended that information on suspected primary abnormalities is included in cytogenetic reports, especially in patients with two or more abnormalities, because this can provide valuable additional information.

An assessment of a 3D EPID-based dosimetry system using conventional two- and three-dimensional detectors for VMAT.

PURPOSE: To provide a 3D dosimetric evaluation of a commercial portal dosimetry system using 2D/3D detectors under ideal conditions using VMAT. METHODS: A 2D ion chamber array, radiochromic film and gel dosimeter were utilised to provide a dosimetric evaluation of transit phantom and pre-treatment 'fluence' EPID back-projected dose distributions for a standard VMAT plan. In-house 2D and 3D gamma methods compared pass statistics relative to each dosimeter and TPS dose distributions. RESULTS: Fluence mode and transit EPID dose distributions back-projected onto phantom geometry produced 2D gamma pass rates in excess of 97% relative to other tested detectors and exported TPS dose planes when a 3%, 3 mm global gamma criterion was applied. Use of a gel dosimeter within a glass vial allowed comparison of measured 3D dose distributions versus EPID 3D dose and TPS calculated distributions. 3D gamma comparisons between modalities at 3%, 3 mm gave pass rates in excess of 92%. Use of fluence mode was indicative of transit results under ideal conditions with slightly reduced dose definition. CONCLUSIONS: 3D EPID back projected dose distributions were validated against detectors in both 2D and 3D. Cross validation of transit dose delivered to a patient is limited due to reasons of practicality and the tests presented are recommended as a guideline for 3D EPID dosimetry commissioning; allowing direct comparison between detector, TPS, fluence and transit modes. The results indicate achievable gamma scores for a complex VMAT plan in a homogenous phantom geometry and contributes to growing experience of 3D EPID dosimetry.

Polychlorinated biphenyl 153 in lipid medium modulates differentiation of human adipocytes.

Emerging evidence indicates that polychlorinated biphenyls (PCBs) are involved in the development of diabetes mellitus in the obese. The purpose of this study was to determine mechanisms by which PCB 153 (2,2´,4,4´,5,5´-hexachloro-biphenyl) could influence diet-induced obesity and insulin resistance during adipogenesis. Lineage of h-ADMSCs was differentiated either as control (differentiation medium only), or with lipid vehicle modeling high fat nutrition (NuTRIflex) or lipid free vehicle (dimethylsulfoxide) for 28 days with or without PCB 153 daily co-exposure (in three concentrations 0.1, 1, and 10 microM). Gene expression analyses were performed using RT-qPCR at days 4, 10, 21, 24, 28; protein levels Akt and phosphorylated Akt (Phospho-Akt) by Western blot at days 4, and 21. PCB 153 treatment of h-ADMSCs only in lipid vehicle was associated with down regulation of key master genes of adipogenesis: PPARgamma, SREBP-1, PPARGC1B, and PLIN2 during the whole process of differentiation; and with increased Akt and decreased Phospho-Akt protein level at day 21. We have shown that PCB 153, in concentration 0.1 microM, has a potential in lipid rich environment to modulate differentiation of adipocytes. Because European and U.S. adults have been exposed to PCB 153, this particular nutrient-toxicant interaction potentially impacts human obesity and insulin sensitivity.

Gamma Radiation Reduced Toxicity of Azoxystrobin Tested on Artemia franciscana.

Fungicide azoxystrobin toxicity was monitored by means of a 96-h biotest with Artemia franciscana nauplius stages after exposure to solutions with concentrations of 0.2, 0.4, 0.6 and 0.8 mg L(-1) irradiated with (60)Co gamma radiation with doses of 1, 2.5, 5 and 10 kGy. The effects of ionization radiation on azoxystrobin toxicity were mainly manifested by a statistically significant reduction of lethality after 72- and 96-h exposure. A maximum reduction of lethality of 72 % was achieved using doses of 1-5 kGy for an azoxystrobin initial concentration of 0.4 mg L(-1) and after 72 h of exposure. At a 96-h exposure, a difference of lethal effects reached up to 70 % for a dose of 10 kGy. The observed effect of gamma ionizing radiation on azoxystrobin toxicity suggest that this approach can be applied as an alternative for a reduction of azoxystrobin residua in food.

Endovascular Management of Acute Embolic Occlusion of the Superior Mesenteric Artery: A 12-Year Single-Centre Experience.

PURPOSE: Retrospective evaluation of 12-year experience with endovascular management of acute mesenteric ischemia (AMI) due to embolic occlusion of the superior mesenteric artery (SMA). MATERIALS AND METHODS: From 2003 to 2014, we analysed the in-hospital mortality of 37 patients with acute mesenteric embolism who underwent primary endovascular therapy with subsequent on-demand laparotomy. Transcatheter embolus aspiration was used in all 37 patients (19 women, 18 men, median age 76 years) with embolic occlusion of the SMA. Adjunctive local thrombolysis (n = 2) and stenting (n = 2) were also utilised. RESULTS: We achieved complete recanalization of the SMA stem in 91.9 %. One patient was successfully treated by surgical embolectomy due to a failed endovascular approach. Subsequent exploratory laparotomy was performed in 73.0 % (n = 27), and necrotic bowel resection in 40.5 %. The total in-hospital mortality was 27.0 %. CONCLUSION: Primary endovascular therapy for acute embolic SMA occlusion with on-demand laparotomy is a recommended algorithm used in our centre to treat SMA occlusion. This combined approach for the treatment of AMI is associated with in-hospital mortality rate of 27.0 %.

[Tumour-stroma interactions in urothelial cancer]. / Tumor-Stroma-Interaktionen im Harnblasenkarzinom.

BACKGROUND: The histopathological structure of malignant tumours involves two essential compartments - the tumour parenchyma with the actual transformed cells, and the supportive tumour stroma. The latter consists of specialized mesenchymal cells, such as fibroblasts, macrophages, lymphocytes and vascular cells, as well as of their secreted products, including components of the extracellular matrix, matrix modifying enzymes and numerous regulatory growth factors and cytokines. In consequence, the tumour stroma has the ability to influence virtually all aspects of tumour development and progression, including therapeutic response. AIM: In this article we review the current knowledge of tumor stroma interactions in urothelial carcinoma and present various experimental systems that are currently in use to unravel the biological basis of these heterotypic cell interactions. RESULTS: For urothelial carcinoma, an extensive tumour stroma is quite typical and markers of activated fibroblasts correlate significantly with clinical parameters of advanced disease. Another clinically important variable is provided by the stromal expression of syndecan-1. CONCLUSION: Integration of markers of activated stroma into clinical risk evaluation could aid to better stratification of urothelial bladder carcinoma patients. Elucidation of biological mechanisms underlying tumour-stroma interactions could provide new therapeutical targets.

Allogeneic stem cell transplantation can improve outcome of AML patients without complete cytogenetic response after induction and consolidation treatment.

UNLABELLED: Our retrospective analysis was performed on 376 consecutive patients diagnosed with AML. A total of 256 (68%) were treated with standard "7+3" induction and high-dose cytarabine and mitoxantrone containing "4+3" consolidation/intensification regimens. Our study focused on patients with presumably very poor prognosis - patients, who did not achieve complete cytogenetic remission (CRc). Twenty-five AML patients without CRc were further analysed for clinical and laboratory parameters. Firstly, the subgroups with or without morphologic CR were compared. Similar cytogenetic abnormalities were observed in both with myelodysplasia related changes being the most common. Complex karyotype with deletion of 5q constituted approximately a third of all karyotypes in both subgroups. There were 1 patient with intermediate risk cytogenetics in the subgroup without morphologic CR and 5 patients in the subgroup with morphologic CR. Interestingly, in 4/25 patients subclones were diminished by the chemotherapy treatment, however cytogenetically less advanced clones proliferated. Secondly, transplanted or nontransplanted patients were analysed. Allogeneic stem cell transplantation (allo-SCT) was found to be the only curative treatment for patients without CRc after 7+3 and 4+3 regimens. In our cohort, 40% of the patients, who underwent allo-SCT, are alive. Importantly, 67% of the patients, who died after allo-SCT, died of causes unrelated to progression of AML. Nonrelapse mortality is therefore one of the fields where survival could be further improved. KEYWORDS: acute myeloid leukaemia, complete cytogenetic remission, cytogenetic abnormalities, stem cell transplantation, nonrelapse mortality.

Discontinuation of tyrosine kinase inhibitors in chronic myeloid leukemia patients - worldwide battlefield.

UNLABELLED: Advances in understanding the pathogenesis of chronic myeloid leukemia (CML) and implementation of the therapy with tyrosine kinase inhibitors (TKI) could be considered as a prototype of successful fight against cancer. However, for an optimally responding patient it is recommended to follow the TKI therapy indefinitely. The question about the possibility of safe TKI treatment discontinuation in certain clinical situations was raised and is currently under close investigation worldwide. Currently, imatinib discontinuation trails have shown that about 60% of eligible patients experienced molecular recurrence within 6 months of treatment discontinuation, while the remaining 40% remained in defined deep molecular response throughout the duration of mostly two years follow-up. Interestingly, retreatment with the same TKI or another TKI was successful in the vast majority of patients demonstrating molecular recurrence of the disease. These findings support the concept of safe TKI treatment discontinuation and its usefulness for a specific subset of CML patients. However, recent data are not sufficient for TKI discontinuation attempts outside clinical trials yet. Because of the high risk of potentially problematic molecular recurrences of the pathological clones, the key question is to find the right predictive marker of TKI discontinuation success, however it stays unsolved yet. This minireview brings a concise summary of this hot topic with a realistic view from clinical routine. KEYWORDS: tyrosine kinase inhibitors, imatinib, discontinuation, chronic myeloid leukemia.

Selected morphological changes in Artemia franciscana after ionizing radiation exposure.

Nauplii of Artemia franciscana were irradiated by the doses of 0.25, 0.5, 1.0, and 2.5 kGy (60)Co. Dimensions of the body length, body width, intestine width, intestine epithelium width, and intestine lumen width, as well as the mutual ratios of dimensions were determined in 126 specimens. Ratios of the body length/body width (3.98, 3.60, 3.59, and 3.45 vs. 4.13 of control group), and ratios of the intestine epithelium width/intestine lumen width (0.64, 0.52, 0.51, and 0.45 vs. 0.85 of control group), according to the doses, were the most important parameters of evaluation of dependence of morphological changes on radiation doses.

Determinants of premature atherosclerosis in children with end-stage renal disease.

Cardiovascular disease is a major cause of morbidity and mortality in young adults with end-stage renal disease (ESRD), but its basis is still not well understood. We therefore evaluated the determinants of atherosclerosis in children with ESRD. A total of 37 children with ESRD (with 31 who had undergone transplantation) were examined and compared to a control group comprising 22 healthy children. The common carotid intima-media thickness (CIMT) was measured by ultrasound as a marker of preclinical atherosclerosis. The association of CIMT with anthropometrical data, blood pressure, plasma lipid levels, and other biochemical parameters potentially related to cardiovascular disease was evaluated. Children with ESRD had significantly higher CIMT, blood pressure, and levels of lipoprotein (a), urea, creatinine, ferritin, homocysteine, and serum uric acid as well as significantly lower values of apolipoprotein A. The atherogenic index of plasma (log(triglycerides/HDL cholesterol)) was also higher in patients with ESRD; however, this difference reached only borderline significance. In addition, a negative correlation was found between CIMT and serum albumin and bilirubin in the ESRD group, and this correlation was independent of age and body mass index. In the control group, a significant positive correlation was observed between CIMT and ferritin levels. Factors other than traditional cardiovascular properties, such as the anti-oxidative capacity of circulating blood, may be of importance during the early stages of atherosclerosis in children with end-stage renal disease.

An alternative to gamma histograms for ROI-based quantitative dose comparisons.

An alternative to gamma (gamma) histograms for ROI-based quantitative comparisons of dose distributions using the gamma concept is proposed. The method provides minimum values of dose difference and distance-to-agreement such that a pre-set fraction of the region of interest passes the gamma test. Compared to standard gamma histograms, the method provides more information in terms of pass rate per gamma calculation. This is achieved at negligible additional calculation cost and without loss of accuracy. The presented method is proposed as a useful and complementary alternative to standard gamma histograms, increasing both the quantity and quality of information for use in acceptance or rejection decisions.

Proteomic profiling of human embryonic stem cell-derived microvesicles reveals a risk of transfer of proteins of bovine and mouse origin.

BACKGROUND AIMS: Microvesicles (MV) shed from the plasma membrane of eukaryotic cells, including human embryonic stem cells (hESC), contain proteins, lipids and RNA and serve as mediators of cell-to-cell communication. However, they may also contain immunogenic membrane domains and infectious particles acquired from xenogenic components of the culture milieu. Therefore, MV represent a potential risk for clinical application of cell therapy. METHODS: We tested the ability of hESC and their most commonly used feeder cells, mouse embryonic fibroblasts (MEF), to produce MV. We found that hESC are potent producers of MV, whereas mitotically inactivated MEF do not produce any detectable MV. We therefore employed a combined proteomic approach to identify the molecules that constitute the major components of MV from hESC maintained in a standard culture setting with xenogenic feeder cells. RESULTS: In purified MV fractions, we identified a total of 22 proteins, including five unique protein species that are known to be highly expressed in invasive cancers and participate in cellular activation, metastasis and inhibition of apoptosis. Moreover, we found that hESC-derived MV contained the immunogenic agents apolipoprotein and transferrin, a source of Neu5Gc, as well as mouse retroviral Gag protein. CONCLUSIONS: These findings indicate that MV represent a mechanism by which hESC communicate; however, they also serve as potential carriers of immunogenic and pathogenic compounds acquired from environment. Our results highlight a potential danger regarding the use of hESC that have previously been exposed to animal proteins and cells.

High molecular weight FGF2: the biology of a nuclear growth factor.

Fibroblast growth factor 2 (FGF2) is one of the most studied growth factors to date. Most attention has been dedicated to the smallest, 18 kDa FGF2 variant that is released by cells and acts through activation of cell-surface FGF-receptor tyrosine kinases. There are, however, several higher molecular weight (HMW) variants of FGF2 that rarely leave their producing cells, are retained in the nucleus and act independently of FGF-receptors (FGFR). Despite significant evidence documenting the expression and intracellular trafficking of HMW FGF2, many important questions remain about the physiological roles and mechanisms of action of HMW FGF2. In this review, we summarize the current knowledge about the biology of HMW FGF2, its role in disease and areas for future investigation.

Lineage specific composition of cyclin D-CDK4/CDK6-p27 complexes reveals distinct functions of CDK4, CDK6 and individual D-type cyclins in differentiating cells of embryonic origin.

OBJECTIVES: This article is to study the role of G(1)/S regulators in differentiation of pluripotent embryonic cells. MATERIALS AND METHODS: We established a P19 embryonal carcinoma cell-based experimental system, which profits from two similar differentiation protocols producing endodermal or neuroectodermal lineages. The levels, mutual interactions, activities, and localization of G(1)/S regulators were analysed with respect to growth and differentiation parameters of the cells. RESULTS AND CONCLUSIONS: We demonstrate that proliferation parameters of differentiating cells correlate with the activity and structure of cyclin A/E-CDK2 but not of cyclin D-CDK4/6-p27 complexes. In an exponentially growing P19 cell population, the cyclin D1-CDK4 complex is detected, which is replaced by cyclin D2/3-CDK4/6-p27 complex following density arrest. During endodermal differentiation kinase-inactive cyclin D2/D3-CDK4-p27 complexes are formed. Neural differentiation specifically induces cyclin D1 at the expense of cyclin D3 and results in predominant formation of cyclin D1/D2-CDK4-p27 complexes. Differentiation is accompanied by cytoplasmic accumulation of cyclin Ds and CDK4/6, which in neural cells are associated with neural outgrowths. Most phenomena found here can be reproduced in mouse embryonic stem cells. In summary, our data demonstrate (i) that individual cyclin D isoforms are utilized in cells lineage specifically, (ii) that fundamental difference in the function of CDK4 and CDK6 exists, and (iii) that cyclin D-CDK4/6 complexes function in the cytoplasm of differentiated cells. Our study unravels another level of complexity in G(1)/S transition-regulating machinery in early embryonic cells.

In vitro labelling of mouse embryonic stem cells with SPIO nanoparticles.

Labelling of mammalian cells with superparamagnetic iron oxide (SPIO) nanoparticles enables to monitor their fate in vivo using magnetic resonance imaging (MRI). However, the question remains whether or not SPIO nanoparticles affect the phenotype of labelled cells. In the present study, the effects of SPIO nanoparticles from two producers on the growth and differentiation of mouse embryonic stem (ES) cells in vitro were investigated. Our observations have shown that SPIO nanoparticles have no effect on the self-renewal of ES cells. Subsequently, we studied the effect of SPIO on the formation of embryoid bodies and neural differentiation of ES cell in monolayer culture. The cavitation of embryoid bodies was partially inhibited and neural differentiation was supported regardless the type of SPIO nanoparticles used. Thus for the first time we documented the effects of SPIO nanoparticles on ES cells and their differentiation.