Functional Hydrogels for Agricultural Application

Ten different hydrogels were prepared and analyzed from the point of view of their use in soil. FT-IR spectra, morphology, swelling ability, and rheological properties were determined for their characterization and appraisal of their stability. The aim was to characterize prepared materials containing different amounts of NPK as mineral fertilizer, lignohumate as a source of organic carbon, and its combination. This study of stability was focused on utility properties in their application in soil-repeated drying/re-swelling cycles and possible freezing in winter. Lignohumate supported the water absorbency, while the addition of NPK caused a negative effect. Pore sizes decreased with NPK addition. Lignohumate incorporated into polymers resulted in a much miscellaneous structure, rich in different pores and voids of with a wide range of sizes. NPK fertilizer supported the elastic character of prepared materials, while the addition of lignohumate shifted their rheological behavior to more liquid. Both dynamic moduli decreased in time. The most stable samples appeared to contain only one fertilizer constituent (NPK or lignohumate). Repeated re-swelling resulted in an increase in elastic character, which was connected with the gradual release of fertilizers. A similar effect was observed with samples that were frozen and defrosted, except samples containing a higher amount of NPK without lignohumate. A positive effect of acrylamide on superabsorbent properties was not confirmed.

Plastic pollution in the deep-sea Giant red shrimp, Aristaeomorpha foliacea, in the Eastern Ionian Sea; an alarm point on stock and human health safety

Plastic litter, including microplastics, is an ever-growing threat adversely affecting a variety of marine organisms; however, their known effects on marine organisms are still lacking. Aristaeomorpha foliacea is a valuable commercial deep-sea species in the Mediterranean Sea. Hence, due to its importance to human consumption, the investigation of plastic impact on these animals is vitally necessary. In this study the occurrence of ingested plastics has been studied in the giant red shrimp for the first time in the eastern Ionian Sea, as well as any possible differences regarding the plastic ingestion per sex, size, year and its relation to shrimp's health condition. A total of 621 individuals were collected from the Essential Habitat of this species in the eastern Ionian Sea. Plastics were contained in the stomachs of 14.65 % of the examined individuals, with an average of 2.97 ± 0.3 items per stomach. The occurrence of plastics was higher in males than in females. The ingested plastics detected were exclusively fibers of different sizes, colors, and shapes (single form or tangled balls). Plastic items size ranged from 0.75 to 110.59 mm. Significant differences in the occurrence of plastic in the stomachs of A. foliacea were found among years, stations and sex, whereas no considerable effect on shrimp's health condition factors was found. The chemical analysis of plastics showed that 83.82 % of fibers were polyester (PET). Among the shrimps with ingested plastics, the immature individuals were predominant (85.18 %). The results of this study aspire to increase the knowledge on plastics ingestion in the Mediterranean, and highlight the various factors that may be involved in this process. This study demonstrates the obvious threats of plastics in commonly edible shrimps and emphasizes the role of this decapod at the trophic chain by transferring plastics to humans.

Fully soluble polymeric foams for in-vial dried blood spot collection and analysis of acidic drugs by capillary electrophoresis

Polymeric foams tailor-made of polyvinylpyrrolidone (PVP) and carboxymethylcellulose/oxidized 6-carboxycellulose (CMC07/OC) composite were proposed as suitable sorbents for the collection and analysis of dried blood spots (DBSs). The PVP and CMC07/OC foams were easy to prepare, enabled collection of minute volumes of capillary blood, and blood drying at ambient temperature. The resulting foams were prepared as small porous discs with uniform dimensions (approx. 6 × 3 mm) and were fully soluble in aqueous solutions. The DBSs were formed in standard capillary electrophoresis (CE) vials fitted with the soluble foam discs and enabled the direct in-vial DBS processing and at-line analysis by CE. The DBSs were pretreated with a simple process, which involved a complete dissolution of the foam disc in an acidic solution and a simultaneous hollow fiber liquid-phase microextraction (HF-LPME) in one step. The complete solubility of the foam disc with the DBS served for a quantitative transfer of all blood components into the eluate and a nearly exhaustive HF-LPME of target analytes, whereas the blood matrix and the polymeric foam components were efficiently retained by the organic solvent impregnated in the walls of the HF. The suitability of the PVP and CMC07/OC foams for the collection and the direct analysis of DBSs was demonstrated by the HF-LPME/CE determination of model acidic drugs (warfarin, ibuprofen, naproxen, ketoprofen, and diclofenac) at therapeutically relevant concentrations. Repeatability of the analytical method was better than 8.1% (RSD), extraction recoveries ranged from 70 to 99% (for PVP foam), calibration curves were linear over two orders of magnitude (R² higher than 0.9991), and limits of detection were less than 44 μg/L (for concentrations in undiluted capillary blood). The soluble polymeric foams exhibited non-significant variations in analyte concentrations for DBSs prepared from blood samples with different hematocrit levels and for aged DBSs (less than 9.2%), moreover, they outperformed standard DBS sampling devices in terms of sample pretreatment time and extraction recovery.

Glycogen, poly(3-hydroxybutyrate) and pigment accumulation in three Synechocystis strains when exposed to a stepwise increasing salt stress

The cyanobacterial genus Synechocystis is of particular interest to science and industry because of its efficient phototrophic metabolism, its accumulation of the polymer poly(3-hydroxybutyrate) (PHB) and its ability to withstand or adapt to adverse growing conditions. One such condition is the increased salinity that can be caused by recycled or brackish water used in cultivation. While overall reduced growth is expected in response to salt stress, other metabolic responses relevant to the efficiency of phototrophic production of biomass or PHB (or both) have been experimentally observed in three Synechocystis strains at stepwise increasing salt concentrations. In response to recent reports on metabolic strategies to increase stress tolerance of heterotrophic and phototrophic bacteria, we focused particularly on the stress-induced response of Synechocystis strains in terms of PHB, glycogen and photoactive pigment dynamics. Of the three strains studied, the strain Synechocystis cf. salina CCALA192 proved to be the most tolerant to salt stress. In addition, this strain showed the highest PHB accumulation. All the three strains accumulated more PHB with increasing salinity, to the point where their photosystems were strongly inhibited and they could no longer produce enough energy to synthesize more PHB.

Ageing effect on conazole fungicide bioaccumulation in arable soils

Widely used conazole fungicides (CFs) belong to the most frequently detected pesticides in Central European arable soils. However, data on their environmental behaviour and bioavailability to soil organisms are surprisingly scarce. In the present laboratory microcosm study prochloraz, tebuconazole, epoxiconazole and flusilazole were applied to 12 different agricultural soils at background levels. Bioaccumulation to earthworm E. andrei and lettuce L. sativa roots and leaves was evaluated in non-aged (biota exposure after addition of pesticides) and aged (exposure started three months later) systems. In contrast with expectations from ageing effect (decrease of bioavailability), bioaccumulation in E. andrei was both reduced and enhanced after ageing depending on soil properties. The reduction of bioaccumulation correlated positively to the percentage of clay but negatively to soil organic matter. The affinity of compost worm E. andrei towards organic matter where hydrophobic pesticide molecules are sorbed is discussed as a possible explanation. An apparent effect of ageing (reduction of bioavailability) was particularly observed in lettuce roots, where bioaccumulation was significantly reduced in time. However, bioaccumulation in leaves changed ambiguously in aged variants among CFs, possibly as a combined result of bioconcentration, dilution by plant growth and metabolism. This study brings first insights into how the bioaccumulation of conazole fungicides is affected by sequestration in agricultural soils. The results indicate that in complex systems, the ageing is not necessarily connected with decrease of bioaccumulation.

Adsorption of epoxiconazole and tebuconazole in twenty different agricultural soils in relation to their properties

Conazole fungicides are currently used pesticides with considerable chronic toxicity and ecotoxicity that are also on EU list for substitution. They enter the soil forming short- or long-term residues. In this study two of their representatives, epoxiconazole (EPC) and tebuconazole (TBC), have been tested with 20 soils from the Czech Republic for their adsorption. Adsorption, by means of Kd coefficients, was compared to "basic" (TOC, pH, clay …) and "advanced" (surface area, minerals ..) soil properties. After doing multivariate analysis of the variables it was apparent that adsorption of both pesticides was highly associated with pH (negatively correlated), and less associated with soil organo-mineral complex (TOC, clay and surface area) and C and N in soil organic matter (OM). Particle sizes or cation exchange capacity (CEC) did not show correlation with adsorption, but showed an association in multidimensional space in factor analysis (FA). Some correlations were revealed between EPC adsorption and soil organic matter parameters. Recalculating Kd to K_oc and to Gibb's free energy (ΔG) and its values indicated that the adsorption of EPC and TBC is mainly weak physical adsorption - partitioning. Also, ΔG values gave better correlation with pH_(H2O) than Kd. Surface area impacted EPC adsorption. From the several soil minerals, kaolinite showed EPC and TBC adsorption. EPC adsorption was not highly influenced with pH changes compared to TBC. The number and types of H-bonds with molecular geometry govern the sorption, which might crucially affect leachibility in soil, and this may indicate that TBC is more leachable than EPC for the same soil.

Early complications in surgery of umbilical and epigastric hernias

INTRODUCTION

Repairs of umbilical and epigastric hernias are common surgical procedures; the choice of the surgical method generally depends on the size of the hernial sac and fascial defect.

METHODS

Data of patients operated on for umbilical or epigastric hernias in our hospital during two years were assessed retrospectively. The study group included 264 patients; 212 had an umbilical hernia and 52 had an epigastric hernia. We assessed epidemiologic and clinical parameters and their correlation with the occurrence of early postoperative complications. We also looked for the recurrence rate, although during only a short follow-up period.

RESULTS

In the case of umbilical hernias, early complications occurred in 6.7% (11/165) after surgery with a simple suture and in 4.3% (2/47) with mesh repair, and the recurrence rates were 3% (5/165) and 21.3% (10/47), respectively. The risk of early complications was significantly higher in larger hernias. The recurrence rate increased with older age, an increased size of the hernial sac and fascial defect, and in patients with type 2 diabetes. In epigastric hernias, early complications occurred in 5.3% (1/19) after surgery with a simple suture and in 6.1% (2/33) with mesh repair. Recurrences only occurred in operations with mesh repair, in 9% (3/33). The risk of early complications was significantly higher in type 2 diabetes patients.

CONCLUSION

Early complications were slightly more frequent in epigastric hernia repairs with mesh implantation, but this was not the case of umbilical hernias. We recommend mesh implantation in larger and borderline sized hernias to reduce the risk of recurrence.

Synergistic effect of bovine platelet lysate and various polysaccharides on the biological properties of collagen-based scaffolds for tissue engineering: Scaffold preparation, chemo-physical characterization, in vitro and ex ovo evaluation

Crosslinked 3D porous collagen-polysaccharide scaffolds, prepared by freeze-drying, were modified with bovine platelet lysate (BPL) and evaluated in terms of chemical, physical and biological properties. Natural antibacterial polysaccharides like chitosan, chitin/chitosan-glucan complex and calcium salt of oxidized cellulose (CaOC) incorporated in collagen scaffolds affected not only chemo-physical properties of the composite scaffolds but also improved their biological properties, especially when BPL was presented. Lipophilic BPL formed microspheres in porous scaffolds while reduced by half their swelling ratio. The resistance of collagen sponges to hydrolytic degradation in water depended strongly on chemical crosslinking varying from 60 min to more than one year. According to in-vitro tests, chemically crosslinked scaffolds exhibited a good cellular response, cell-matrix interactions, and biocompatibility of the material. The combination of collagen with natural polysaccharides confirmed a significant positive synergistic effect on cultivation of cells as determined by MTS assay and PicoGreen method, as well as on angiogenesis evaluated by ex ovo Chick Chorioallantoic Membrane (CAM) assay. Contrary, modification only by BLP of pure collagen scaffolds exhibited decreased biocompatibility in comparison to unmodified pure collagen scaffold. We propose that the newly developed crosslinked collagen sponges involving bioactive additives could be used as scaffold for growing cells in systems with low mechanical loading in tissue engineering, especially in dermis replacement, where neovascularization is a crucial parameter for successful skin regeneration.

Incidence of Adenovirus Infection in Hematopoietic Stem Cell Transplantation Recipients: Findings from the AdVance Study

Adenovirus (AdV) is an increasingly recognized threat to recipients of allogeneic hematopoietic stem cell transplantation (allo-HCT), particularly when infection is prolonged and unresolved. AdVance is the first multinational, multicenter study to evaluate the incidence of AdV infection in both pediatric and adult allo-HCT recipients across European transplantation centers. Medical records for patients undergoing first allo-HCT between January 2013 and September 2015 at 50 participating centers were reviewed. The cumulative incidence of AdV infection (in any sample using any assay) during the 6 months after allo-HCT was 32% (95% confidence interval [CI], 30.9% to 33.4%) among pediatric allo-HCT recipients (n = 1736) and 6% (95% CI, 4.7% to 6.4%) among adult allo-HCT recipients (n = 2540). The incidence of AdV viremia ≥1000copies/mL (a common threshold for initiation of preemptive treatment) was 14% (95% CI, 13.0% to 14.8%) in pediatric recipients and 1.5% (95% CI, 1.1% to 2.0%) in adult recipients. Baseline risk factors for developing AdV viremia ≥1000copies/mL included younger age, use of T cell depletion, and donor type other than matched related. Baseline demographic factors were broadly comparable across patients of all ages and identified by multivariate analyses. Notably, the incidence of AdV infection decreased stepwise with increasing age; younger adults (age 18 to 34 years) had a similar incidence as older pediatric patients (<18 years). This study provides a contemporary multicenter understanding of the incidence and risk factors for AdV infection following allo-HCT. Our findings may help optimize infection screening and intervention criteria, particularly for younger at-risk adults.

Quantitative Raman Spectroscopy Analysis of Polyhydroxyalkanoates Produced by Cupriavidus necator H16

We report herein on the application of Raman spectroscopy to the rapid quantitative analysis of polyhydroxyalkanoates (PHAs), biodegradable polyesters accumulated by various bacteria. This theme was exemplified for quantitative detection of the most common member of PHAs, poly(3-hydroxybutyrate) (PHB) in Cupriavidus necator H16. We have identified the relevant spectral region (800–1800 cm⁻¹) incorporating the Raman emission lines exploited for the calibration of PHB (PHB line at 1736 cm⁻¹) and for the selection of the two internal standards (DNA at 786 cm⁻¹ and Amide I at 1662 cm⁻¹). In order to obtain quantitative data for calibration of intracellular content of PHB in bacterial cells reference samples containing PHB amounts—determined by gas chromatography—from 12% to 90% (w/w) were used. Consequently, analytical results based on this calibration can be used for fast and reliable determination of intracellular PHB content during biotechnological production of PHB since the whole procedure—from bacteria sampling, centrifugation, and sample preparation to Raman analysis—can take about 12 min. In contrast, gas chromatography analysis takes approximately 8 h.

Appearance of cytomegalovirus-specific T-cells predicts fast resolution of viremia post hematopoietic stem cell transplantation

BACKGROUND

Cytomegalovirus (CMV) specific T-cells are known to provide long-term control of CMV reactivation, which is a frequent complication of hematopoietic stem cell transplantation. We have studied 58 pediatric patients after hematopoietic stem cell transplantation who suffered from CMV reactivation to reveal which functional T cell subset is best correlating with successful reactivation resolution and which protects from reactivation episode.

METHODS

Detection of 30 combinatorial subsets of four types of response to ex vivo CMV stimulation (IFNγ secretion, IL-2 secretion, CD40L upregulation and degranulation) that were detectable on either CD8+ or CD4+ T cells through flow cytometry intracellular cytokine staining was used.

RESULTS

We found that the presence of CD8+ dual positive (IFNγ+ and IL-2+) cells is the most accurate functional parameter that can predict fast resolution of CMV reactivation. Next, we show that the presence of CD8+ dual positive (IFNγ+ and IL-2+) and CD8+ IFNγ+ cells provides a protective effect (a hazard risk of 0.28 (confidence interval 0.18 - 0.43) and 0.45 (CI 0.27 - 0.75), respectively) and the presence of corticotherapy increases the risk of reactivation (HR 2.47 (CI 1.82-3.36)). Thus, a patient without corticotherapy and with both of the critical T cell subsets present has a cumulative 19.6 times lower risk of developing CMV reactivation than a patient on corticotherapy and without CD8+ dual positive (IFNγ+ and IL-2+) or CD8+ IFNγ+ cells.

CONCLUSIONS

We have established parameters of CMV specific functional response ex vivo that can be used in assisting clinical management of patients with CMV reactivation. © 2015 International Clinical Cytometry Society.

On the role of humic acids' carboxyl groups in the binding of charged organic compounds

Interactions of humic acids (HAs) with two cationic dyes (methylene blue and rhodamine 6G) were studied using a unique combination of diffusion and partitioning studies in HAs, containing hydrogels and batch sorption experiments. In order to investigate the involvement of carboxyl groups of HAs in these interactions, all experiments were performed for both, the original lignite HAs and HAs with selectively methylated carboxyls. The results of the diffusion experiments confirm that the interactions between the solute and humic substances have a strong impact on the rate of diffusion process. Surprisingly, the effect is almost equally approved for original and methylated HAs. On the other hand, the results of batch sorption experiments show strong improvement of the sorption capacity (methylated HAs), which is explained by changed morphology of alkylated HAs. The comparison of the results of diffusion and adsorption experiments shows that the diffusion experiments simulate the transport of solutes in natural humics containing environment more reasonably.

[The prospects for children with acute lymphoblastic leukemia of being cured has increased in the Czech Republic in the 21st century to 90% - outcome of the ALL-IC BFM 2002 trial]

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most frequent childhood malignancy. Treatment has been unified in the middle of 1980 in the Czech Republic. In 2002-2007 children and adolescents with acute lymphoblastic leukemia were treated in an international randomized trial ALL-IC BFM 2002 in the Czech Republic. 291 patients aged 1-18 years were enrolled; infants below 1 year entered a separate trial.

METHODS AND RESULTS

Patients were stratified into three risk groups according to their age, initial leukocyte count, prednisone response, presence of fusion genes BCR/ABL or MLL/AF4, bone marrow D+15 and remission status D+33. The whole therapy took 24 months. Randomized late intensification compared standard BFM therapy with extended, usually more intensive experimental treatment. The median follow-up was 8.7 years. Complete remission was achieved in 97.9% patients, 1% died in remission. 11% of children relapsed, 1.7% with CNS involvement. Six children (2.1%) developed secondary malignancy. Event free survival (EFS) 8 years from diagnosis was 83.5%, overall survival (OS) 91.4%. EFS and OS of the risk groups were: standard risk: 89.4%; 98.1%; intermediate risk: 82.6%; 89.6%; high risk: 68.8%; 78.1%. Male sex and age above 10 years were adverse prognostic factors.

CONCLUSIONS

In comparison with the previous trial ALL-BFM 95, significant improvement was achieved.

[Guidelines for antifungal prophylaxis, diagnosis and therapy in pediatric hematology and oncology - a review of literature and expert recommendations]

OBJECTIVES

Problems with importing non-registered medicines for treating rare life-threatening infectious diseases led to establishment of the Emergency Anti-Infective Drug Reserve (EAIDR) for the Czech Republic.

METHODS

Thirteen anti-infective drugs are included in the project: antisera against rabies virus, varicella-zoster virus, and botulinum toxin; antituberculosis drugs (intravenous rifampicin and isoniazid; capreomycin, cycloserine, and clofazimine); antiparasitics (intravenous quinine, primaquine, meglumine antimoniate, and praziquantel); and pentamidine. These drugs are imported according to the Czech drug legislation (specific drug availability programs). Realization: The project, approved by the Czech Ministry of Health in September 2013, was started in January 2014. The anti-infective drugs sufficient for 2-4 patients are permanently available in the Toxicological Information Center (TIC) in Prague. The medicines can be applied in any hospital throughout the Czech Republic within several hours.

CONCLUSIONS

All but three drugs are available at present; the remaining ones will be imported after new batches of these drugs are released.

[Invasive mucormycosis in pediatric hematology patients--single-center experience from 2005-2010]

BACKGROUND

Mucormycosis is an invasive fungal disease severely complicating treatment of patients with hematologic diseases. Effective therapy is represented by the combination of surgery and amphotericin B administration and early initiation of the therapy is necessary for favorable outcome. The first clinical symptoms are usually non-specific and this can lead to late therapy onset. The objective of this retrospective work was to determine the frequency, risk factors and outcome of invasive mucormycosis in pediatric hematology patients.

MATERIAL AND METHODS

The study cohort comprised 399 patients diagnosed with hematologic diseases in the Department of Pediatric Hematology and Oncology (DPHO), University Hospital Motol, Prague between 2005 and 2010. Risk factors for the development of mucormycosis, clinical symptoms and radiology and laboratory results were retrospectively evaluated. So were the therapy used and outcomes. The findings were analyzed using Fisher's exact test.

RESULTS

During the selected period, mucormycosis was detected in 8 patients diagnosed with hematologic disease. The incidence of mucormycosis was 1.75 %. These conditions accounted for 20.6 % of all mycoses. In five patients, it was found as isolated infection; three cases were associated with other mycoses (one with candidiasis, two with aspergillosis). The most frequent underlying disease was acute leukemia; the most common risk factor was severe prolonged neutropenia (median duration 21.5 days). Three of eight patients survived mucormycosis, a mortality rate of 62.5 %. The effective therapy was amphotericin B administration in three patients (p = 0.02); in two of them, it was combined with radical surgery.

CONCLUSION

In the cohort, the proportion of mucormycosis cases was surprisingly high when compared with other fungal diseases. Continuous surveillance of mucormycosis in the DPHO is needed. There was no significant influence of the combination of radical surgery and amphotericin B administration as compared to administration of amphotericin B alone. Nevertheless, according to the published data, we consider this approach as an optimal strategy for the management of mucormycosis at the present time.

Expansion of T helper type 17 lymphocytes in patients with chronic granulomatous disease

Hyper-immunoglobulin (Ig)E syndrome (HIES) is a primary immunodeficiency associated with mutations in STAT3 resulting in impaired development of T helper type 17 (Th17) lymphocytes. HIES patients with a reduced frequency of Th17 cells present with infections caused by Staphylococcus aureus and/or Candida strains. The same spectrum of pathogens is present in patients with chronic granulomatous disease (CGD).We analysed the characteristics of the Th17 compartment in HIES and CGD. HIES patients showed very low numbers of Th17 cells. By contrast, the frequency of Th17 cells and production of Th17-derived cytokines was significantly higher among CGD patients when compared to both control samples and HIES. Naive CD4(+) cells in CGD patients had a normal capacity to differentiate into IL-17-producing cells and the numbers of Th17 cells in the CGD patients normalized following successful bone marrow transplantation. Our findings complement recent data on the importance of Th17 cells for elimination of infections with C. albicans and S. aureus.

Diffusion experiments as a new approach to the evaluation of copper transport in humics-containing systems

Diffusion measurements seem to provide a valuable approach to mapping studies on heavy metal transport in systems containing humic substances. The paper deals with the diffusion of cupric ions in a humic hydrogel. The diffusion coefficients of Cu2+ in this medium were determined using in-diffusion from the constant source, diffusion couple and instantaneous planar source. The applicability of the experimental arrangements and mathematical description of metal ion transport are discussed in terms of the influence of complexation of Cu2+ with humic acids. All determined diffusion coefficients of Cu2+ in humic gel were lower but of the same order of magnitude compared with that obtained in water.