Synthetic Carriers Research Articles

The targeted LHRH analog AEZS-108 alters expression of genes related to angiogenesis and development of metastasis in uveal melanoma.

Uveal melanoma (UM) is the most common malignant tumor of the eye. Recently, we have established that 46% of UM specimens express LHRH receptors. This finding supports the idea of a LHRH receptor-targeted therapy of UM patients. Cytotoxic analog of LHRH, AEZS-108 exhibits effective anti-cancer activity in LHRH-receptor positive cancers. AEZS-108 is a hybrid molecule, composed of a synthetic peptide carrier and the cytotoxic doxorubicin (DOX). In the present study, we investigated AEZS-108 induced cytotoxicity and the altered mRNA expression profile of regulatory factors related to angiogenesis and metastasis in LHRH receptor positive OCM3 cells. Our results show that AEZS-108 upregulates the expression of MASPIN/SERPINB5 tumor suppressor gene, which is downregulated in normal uvea and UM specimens independently from the LHRH receptor-ligand interaction. AEZS-108 also substantially downregulates hypoxia-inducible factor 1 alpha (HIF1A) expression. In order to investigate the mechanism of the induction of MASPIN by AEZS-108, OCM3 cells were treated with free DOX, D-Lys6 LHRH analog, or AEZS-108. qRT- PCR analysis revealed in OCM3 cells that AEZS-108 is a more potent inducer of MASPIN than free DOX. In conclusion, we show for the first time that AEZS-108 has a major impact in the regulation of angiogenesis thus plays a potential role in tumor suppression. Taken together, our results support the development of novel therapeutic strategies for UM focusing on LHRH receptors.

Bioengineered elastin- and silk-biomaterials for drug and gene delivery.

Advances in medical science have led to diverse new therapeutic modalities, as well as enhanced understanding of the progression of various disease states. These findings facilitate the design and development of more customized and exquisite drug delivery systems that aim to improve therapeutic indices of drugs to treat a variety of conditions. Synthetic polymer-based drug carriers have often been the focus of such research. However, these structures suffer from challenges with heterogeneity of the starting material, limited chemical features, complex functionalization methods, and in some cases a lack of biocompatibility. Consequently, protein-based polymers have garnered much attention in recent years due to their monodisperse features, ease of production and functionalization, and biocompatibility. Genetic engineering techniques enable the advancement of protein-based drug delivery systems with finely tuned physicochemical properties, and thus an expanded level of customization unavailable with synthetic polymers. Of these genetically engineered proteins, elastin-like proteins (ELP), silk-like proteins (SLP), and silk-elastin-like proteins (SELP) provide a unique set of alternatives for designing drug delivery systems due to their inherent chemical and physical properties and ease of engineering afforded by recombinant DNA technologies. In this review we examine the advantages of genetically engineered drug delivery systems with emphasis on ELP and SLP constructions. Methods for fabrication and relevant biomedical applications will also be discussed.

Genetically engineered haemoglobin wrapped covalently with human serum albumins as an artificial O2 carrier.

We describe the synthesis and O2 affinity of genetically engineered human adult haemoglobin (rHbA) wrapped covalently with recombinant human serum albumins (rHSAs) as an artificial O2 carrier used for a completely synthetic red blood cell (RBC) substitute. Wild-type rHbA [rHbA(wt)] expressed in yeast species Pichia pastoris shows an identical amino acid sequence and three-dimensional structure to those of native HbA. It is particularly interesting that two orientations of the prosthetic haem group in rHbA(wt) were aligned by gentle heating in the natural form. Covalent wrapping of rHbA(wt) with three rHSAs conferred a core-shell structured haemoglobin-albumin cluster: rHbA(wt)-rHSA3. Three variant clusters containing an rHbA mutant core were also created: Leu-β28 → Phe, Leu-β28 → Trp, and Leu-β28 → Tyr/His-β63 → Gln. Replacement of Leu-β28 with Trp decreased the distal space in the haem pocket, thereby yielding a cluster with moderately low O2 affinity which is nearly the same as that of human RBC.

Oxygen carrier in core-shell fibers synthesized by coaxial electrospinning enhances Schwann cell survival and nerve regeneration.

Rationale: Local hypoxia is a challenge for fabrication of cellular grafts and treatment of peripheral nerve injury. In our previous studies, we demonstrated that perfluorotributylamine (PFTBA) could provide short term oxygen supply to Schwann cells (SCs) and counteract the detrimental effects of hypoxia on SCs during the early stages of nerve injury. However, the quick release of oxygen in PFTBA compromised its ability to counteract hypoxia over an extended time, limiting its performance in peripheral nerve injury.Methods: In this study, PFTBA-based oxygen carrier systems were prepared through coaxial electrospinning to prolong the time course of oxygen release. Core-shell structures were fabricated, optimized, and the oxygen kinetics of PFTBA-enriched core-shell fibers evaluated. The effect of core-shells on the survival and function of SCs was examined in both 2D and 3D systems as well as in vivo. The system was used to bridge large sciatic nerve defects in rats.Results: PFTBA core-shell fibers provided high levels of oxygen to SCs in vitro, enhancing their survival, and increasing NGF, BDNF, and VEGF expression in 2D and 3D culture systems under hypoxic condition. In vivo analysis showed that the majority of GFP-expressing SCs in the PFTBA conduit remained viable 14 days post-implantation. We found that axons in PFTBA oxygen carrier scaffold improved axonal regeneration, remyelination, and recovery.Conclusion: A synthetic oxygen carrier in core-shell fibers was fabricated by the coaxial electrospinning technique and was capable of enhancing SC survival and nerve regeneration by prolonged oxygen supply. These findings provide a new strategy for fabricating cellular scaffolds to achieve regeneration in peripheral nerve injury treatment and other aerobic tissue injuries.

Conjugation of new DNA vaccine with polyethylenimine induces cellular immune response and tumor regression in neuroblastoma mouse model.

To estimate immunogenicity and antitumor effect of new DNA vaccine against neuroblastoma using tyrosine hydroxylase as an antigen and linear polyethylenimine (PEI) 20kDa as a synthetic DNA carrier in syngeneic mouse tumor model. DNA vaccine was made by cloning the tyrosine hydroxylase minigene fused to the potato virus X coat protein gene into the expression vector. The A/J mice were vaccinated by three intramuscular injections. For immunogenicity study, immune response was estimated by target cells cytotoxicity assay, interferon-gamma production in enzyme-linked immunospot assay and antigen-specific antibodies in 14days after the final vaccination. Antitumor effect was assessed by measurement of tumor volume and event-free survival rate in mice with engrafted NB41A3murine neuroblastoma cells following three intramuscular injections of the vaccine: 7days before, 5and 10days after tumor engraftment. The immune response was also assessed on the 30th day after tumor engraftment. The immunogenicity and antitumor effect of the vaccine in the form of aqueous solution of DNA and DNA-PEI conjugate were compared. Splenocytes cytotoxicity was the highest in the group of DNA-PEI vaccines (37.3 ± 6.9% lysis of target cells) compared with the unconjugated DNA vaccine (26.2 ± 4.0%) and placebo control (21.9 ± 3.7%). The production of interferon-gamma in the enzyme-linked immunospot assay was about ten times higher in the DNA-PEI group than in the other groups. The vaccine slowed or prevented the growth of the tumor. Mice vaccinated with the DNA-PEI vaccine had significantly better survival compared to control group (p < 0.0003). DNA vaccine against tyrosine hydroxylase, administered as a DNA-PEI 20kDa conjugate, slows down the growth of neuroblastoma cells engrafted to mice.

Bacterial nanocellulose as novel carrier for intestinal epithelial cells in drug delivery studies.

Synthetic cell carriers (A) represent common scaffold structures for the development of cell-based in vitro models of the human intestine but due to their low porosity or unwanted molecular adhesion effects, synthetic carriers can negatively affect cell function. Alternative scaffolds such as natural extracellular matrices (ECMs) (B) were shown to overcome some of the common drawbacks. However, their fabrication is time-consuming, less well standardized and not entirely conform to the 3R principle (replacement, reduction, refinement). Nowadays, biopolymers such as bacterial nanocellulose (BNC) (C) represent interesting scaffold materials for innovative tissue engineering concepts, as they can be generated in a faster and more standardized process workflow without the need for animal material. In this study, we demonstrate the BNC as suitable carrier for the development of Caco-2-based in vitro models of the human intestine. The BNC-based models exhibit organ-specific properties comprising typical cellular morphologies, characteristic protein expression profiles, representative ultrastructural features and the formation of a tight epithelial barrier. The proof of in vivo-like transport activities further validates the high quality of the BNC-based Caco-2 models. In summary, this illustrates the BNC as alternative bioscaffold of non-animal origin to develop functional organ models in vitro.

PURIFICATION OF WATER FROM PHENOL BY BACTERIA OF THE GENUS PSEUDOMONAS IMMOBILIZED ON NATURAL AND SYNTHETIC CARRIERS

Aim. Optimization of the process of water purification from phenol using bacteria of the genus Pseudomonas (P. cepacia ONU327, P. fluorescens ONU328, P. maltophilia ONU329) immobilized on natural and synthetic carriers. Methods. The concentration of phenol in water was determined by extraction-photometric method using 4-aminoantipyrin. For purification of water from phenol (with a concentration of 200 mg / l) non-pathogenic individual strains of bacteria P. fluorescens ONU328, P. maltophilia ОNU329, P. cepacia ОNU327, immobilized on carriers of different nature (zeolite, mussel doors, river sand, ceramic rings, activated carbon, high peat, synthetic carrier type "VIYA"). Results. There were experimentally confirmed that adhesion of cells of the bacterial strains of P. cepacia ONU327, P. fluorescens ONU328, P. maltophilia ONU329 to zeolite, river sand (which practically do not sorb phenol) contributed to the effective biodegradation of phenol by 96–100% (depending on the selected strain bacteria). The residual concentration of phenol in water during its treatment (for 11 days) by cells of P. fluorescens ONU328 strain or P. maltophilia ONU329 strain immobilized on zeolite decreased from 200 mg / l to 8.0±0.95 mg / l (water purification from phenol (α) – 96%) and up to 2.0±0.14 mg / l (α = 99%) – when using immobilized cells of the strain P. cepacia ONU327. It was established that when river microorganisms-destructors were immobilized on the river sand, the residual concentration of phenol in water on the 11th day of treatment was 6.0 ± 0.55 mg / l (α = 97%) and 2.0±0.14 mg / l (α = 99%) – respectively for the strains of P. maltophilia ONU329 and P. fluorescens ONU328; and reached the level of maximum permissible concentration (MPC = 0.001 mg / l) – in the case of river cells of strain P. cepacia ONU327 immobilized in the sand of the river. It was established experimentally that the acceleration of water purification from phenol occurred when using cells of bacteria of the genus Pseudomonas (P. cepacia ОNU327, P. fluorescens ONU328) immobilized on ceramic tubes and a fibrous nozzle of the “VIYA” type. Within 5 days of exposure, the degree of water purification from phenol immobilized on the fibrous attachment of the VIYA type by destructive microorganisms, taking into account the control correction (native unmodified sorbent of the VIA type) reached 97% – as a result of the action of the strain P. cepacia ONU327; and 99% – as a result of the strain P. fluorescens ONU328. Conclusion. To accelerate the purification of water from phenol (for 5 days) by 97–99%, it is recommended to use the strains of the bacteria P. cepacia ONU327 and P. fluorescens ONU328 immobilized on a fibrous nozzle of the type "VIYA". Full dephenolization of water is observed when it is treated with the strains of bacteria P. cepacia ONU327, P. fluorescens ONU328, which are immobilized separately on activated carbon, river sand (for the strain P. cepacia ONU327) and on the mussel doors (for the strain P. fluorescens ONU328), respectively.

Characterisation of Natural Oils as Carrier Fluids for Magnetorheological Fluids

The field of application of Magnetorheological fluids (MRF) is widening. The carrier fluids being used now are synthetic, expensive and non-biodegradable. Hence, there is a need for looking for better and inexpensive alternatives. This study was intended to uncloak alternatives to the synthetic carrier fluids by taking four natural oils and conducting various tests. The four natural oils, viz, Simarouba Oil, Mahua Oil, Groundnut oil, Flaxseed oil and synthetic Silicone oil were taken and tests concerning Magnetorheological fluids like density, kinematic viscosity, flash and fire point, pour point, etc., were conducted according to standards in a licensed laboratory. Based on the various tests conducted, the four natural oils have shown remarkable potential compared with commonly used silicone oil to be used as carrier fluids.

Exosome Production, Isolation and Characterization from A549 Epithelial Carcinoma Cells

Exosomes are natural nanoparticles that special features have been started to be used for recent years in the treatment of cancer as a natural, homogeneous, nanosized, targeted vesicles (~ 50- 100 nm). They have high avidity (many conformational attachment) to attach onto targeted cancer cell surfaces. They are composed of bioactive double-layered lipid layers in which their original nature has the adhesive proteins interacting with the cancer cell membrane easily. In this study, the exosomes of non-small cell lung cancer A549 epithelial carcinoma cells were investigated for their potential to be the natural or synthetic drug carrier. Firstly, exosomes of A549 cell line were produced in exosome-free media. Immediately after, isolation of their exosomes were realized by using ultracentrifugation procedure. SEM image, particle size, zeta potential, exosomal RNA analysis and Protein Content by Bradford assays were performed. Findings (Size: 168 nm; zeta: -16mV) on the properties of A549 cell exosomes proved their potential to be used as the drug carrier for cancer cell therapy.

Synthesis of Dopamine by Non-Dopaminergic Neurons of the Rat Tuberoinfundibular System during Ontogeny

Abstract—In the early 2000s, it was shown that dopamine is synthesized not only by dopaminergic neurons that possess the necessary set of enzymes, tyrosine hydroxylase and aromatic L-amino acid decarboxylase (AAD), but also by non-dopaminergic (monoenzymatic) neurons containing one of the enzymes. In this case, L-3,4-dihydroxyphenylalanine (L-DOPA), which is synthesized in neurons containing tyrosine hydroxylase, is transferred to neurons containing AAD, where dopamine is synthesized. The evidence for cooperative dopamine synthesis in our previous studies was a decrease in the total dopamine synthesis during incubation of a suspension of neurons of the tuberoinfundibular system (TIS) of fetuses or TIS slices from adult rats in the presence of a neutral amino acid that is a competitive inhibitor of the membrane L-DOPA carrier. In this work, the previously applied methodological approach was improved by using only sections of TIS and 2-amino-2-norbornanecarboxylic acid, a synthetic non-metabolizable L-DOPA membrane carrier inhibitor. This made it possible to confirm the presence of cooperative dopamine synthesis in TIS in fetuses and adult rats, and to obtain additional evidence of this synthesis in the form of an increase in the intercellular content of L-DOPA during inhibition of its membrane carrier. In addition, using an improved method we quantitatively characterized the synthesis of dopamine by nondopaminergic neurons and compared it in fetuses and adult rats. It was shown that the proportion of cooperative dopamine synthesis from the total dopamine synthesis by monoenzymatic and dopaminergic neurons in TIS in rat fetuses is 1.8 times higher than in adult animals. A six-fold increase in the synthesis of dopamine by rat TIS monoenzymatic neurons from the end of the prenatal period to adulthood are of particular interest from the standpoint of the functional role of dopamine produced by monoenzymatic neurons. Thus, in ontogeny, the proportion of dopamine synthesis by nondopaminergic monoenzymatic neurons in the general synthesis of dopamine is significantly reduced and the absolute value of cooperative dopamine synthesis increases by many times.

The binuclear cluster of [FeFe] hydrogenase is formed with sulfur donated by cysteine of an [Fe(Cys)(CO)2(CN)] organometallic precursor

The enzyme [FeFe]-hydrogenase (HydA1) contains a unique 6-iron cofactor, the H-cluster, that has unusual ligands to an Fe-Fe binuclear subcluster: CN-, CO, and an azadithiolate (adt) ligand that provides 2 S bridges between the 2 Fe atoms. In cells, the H-cluster is assembled by a collection of 3 maturases: HydE and HydF, whose roles aren't fully understood, and HydG, which has been shown to construct a [Fe(Cys)(CO)2(CN)] organometallic precursor to the binuclear cluster. Here, we report the in vitro assembly of the H-cluster in the absence of HydG, which is functionally replaced by adding a synthetic [Fe(Cys)(CO)2(CN)] carrier in the maturation reaction. The synthetic carrier and the HydG-generated analog exhibit similar infrared spectra. The carrier allows HydG-free maturation to HydA1, whose activity matches that of the native enzyme. Maturation with 13CN-containing carrier affords 13CN-labeled enzyme as verified by electron paramagnetic resonance (EPR)/electron nuclear double-resonance spectra. This synthetic surrogate approach complements existing biochemical strategies and greatly facilitates the understanding of pathways involved in the assembly of the H-cluster. As an immediate demonstration, we clarify that Cys is not the source of the carbon and nitrogen atoms in the adt ligand using pulse EPR to target the magnetic couplings introduced via a 13C3,15N-Cys-labeled synthetic carrier. Parallel mass-spectrometry experiments show that the Cys backbone is converted to pyruvate, consistent with a cysteine role in donating S in forming the adt bridge. This mechanistic scenario is confirmed via maturation with a seleno-Cys carrier to form HydA1-Se, where the incorporation of Se was characterized by extended X-ray absorption fine structure spectroscopy.

DESTRUCTION OF PHENOL AT THE FORMATION OF POLYVIDOUS BIOFILM ON NATURAL AND SYNTHETIC CARRIERS IN THE BIOFILTER

Aim. To determine the effectiveness of the process of water purification from phenol by microorganisms-destructors in the formation of a polyvidiofilm biofilm on natural and synthetic carriers in a biofilter. Methods. An association of phenol bacterium destructors — Aeromonas ichthiosmia ONU552, Basillus subtilis ONU551, Pseudomonas maltophilia ONU329, Pseudomonas fluorescens ONU328, Pseudomonas cepacia ONU327 was used. Stained biofilms were stained with 1% acridine orange solution. Microscopy of the samples was carried out under a Carl Zeiss fluorescence microscope and a Carl Zeiss, Primo Star light microscope with photo fixation. The concentration of phenol in water was determined by the extraction-photometric method using 4-aminoantipyrin. Results. Using fluorescence microscopy, it was confirmed that bacteria used for purification of water from phenol - destructors formed a biofilm in a biofilter on carriers of different nature – ceramic tubes, mussel valves, peat, zeolite, activated carbon, synthetic media such as "VIYA", sand. In laboratory conditions, the effectiveness of the operation of a column-based biofilter of flow-up-stage type with layer-by-layer complex loading of sorbents during purification of phenol-containing water (initial concentration of phenol – 300 mg/l) was confirmed. After 2 hours of the biofilter operation, the degree of water purification was 40% (residual phenol concentration in water 180±17.2 mg/ l), which was associated with phenol sorption on carriers; during biodegradation, it reached 90% (residual phenol concentration in water – 29.5±2.8 mg/l) on the 6th day. In the following days, the efficiency of the biofilter with continuous intake of phenol-contaminated water was at the level of 50–75%, and in the stationary-cyclic mode reached 80–90% (the concentration of phenol in the water varied from 29.5±2.8 to 60±5.7 mg/l). Conclusion. The new microbial consortium forms a biofilm on natural and synthetic filter carriers, which contributes to the effective purification of water from phenol and the flow-through biofilter operation time (up to 2 months) without additional regeneration.

New Anionophores and Insights into Ion-Transport-Induced Cancer Cell Death

In this issue of Chem, Pellois, Gabbai, and colleagues introduce pnictogenium cations as useful transmembrane anion transporters, and Gale, Sessler, Injae, and co-workers provide insights into the cellular mechanism elicited by some of these compounds, leading to the induction of apoptosis in cancer cells.

Assembling structurally customizable synthetic carriers of siRNA through thermodynamically self-regulated process

This study demonstrates that our previously reported polywraplex, a synthetic siRNA carrier consisting of a uni-molecular polyplex core of customizable size and a self-assembled tri-block copolymer envelop, may be constructed using dendrimers as the crosslinking junctions. Replacing the branched low molecular weight PEI with polyamidoamine (PAMAM) dendrimer in the zeta potential regulated polymerization resulted in the similar network structured cationic polymer with electron microscopically visible crosslinking junctions. This visibility may offer a convenient way to characterize the molecular structure of the rationally designed networked siRNA-packing cationic polymer without altering its chemical properties and biologic functions. A series of physical-chemical characterizations and biological assays, comprising size, zeta potential, pre-phagocytic siRNA leaking and degradation, and silencing of functional genes, confirmed that the advanced properties of polywraplexes remained with the dendrimer junctions. Although sixth generation PAMAM dendrimer was used as the crosslinking junctions in the size-customizable polymerization for electron microscopic observation, lower generation dendrimer should also work in case more practical and structurally defined cationic polymer is needed.

Chemical-looping combustion in a 100 kW unit using a mixture of synthetic and natural oxygen carriers – Operational results and fate of biomass fuel alkali

Biomass fuel use in chemical looping combustion enables negative CO2 emissions through BECCS (Bio-Energy Carbon Capture and Storage). Effective biomass utilization in CLC requires an economical and effective oxygen carrier to achieve high fuel conversion, effective CO2 capture, and management of the harmful effects of biomass alkali release (bed agglomeration, oxygen carrier deactivation, fouling and corrosion). These issues were addressed in 100 kW CLC pilot experiments.Building on previous work, a mixture of a synthetic calcium manganite perovskite and natural ilmenite was used as the oxygen carrier. Four biomass fuels of varied alkali content were tested: black pellets of steam-exploded stem wood (BP), BP impregnated with K2CO3, a mixture of 50% BP with 50% straw pellets, and wood char. Experiments showed high fuel conversion and very high CO2 capture, with overall performance exceeding that of ilmenite and manganese ore. More than 95% gas conversion was achieved with black pellets at around 950 °C.The fate of biomass alkali, previously virtually unknown in CLC research, was explored by implementing online surface-ionization-based measurement of alkali released in the flue gases of the fuel reactor (FR) and air reactor (AR). Release levels were found to correlate with the fuel alkali content. The flue gas measurements and bed material elemental analyses suggest that most of the fuel alkali are accumulated in the oxygen carrier. Unexpectedly, it was found that flue gas alkali release occurs in both the FR and AR, with AR exhibiting an equal or higher rate of release vs. the FR.

Evaluating redox reactivity of CuO-based oxygen carriers synthesized with organometallic precursors

The highly efficient CuO-based oxygen carrier is prospectively applied in chemical-looping combustion process. The metal precursors and synthetic methods greatly affect the performance of the synthetic CuO-based oxygen carriers. The inorganic precursors are commonly used to synthesize CuO-based oxygen carriers, while the organometallic precursors are scarcely adopted. In this work, the organometallic copper precursor [copper (II) acetate] and three other different organometallic support precursors (magnesium l-lactate hydrate, silicon tetraacetate and magnesium acetate) were adopted to produce CuO-based oxygen carriers via the methods of wet-mixing and spray-drying, respectively. It is found that the synthetic oxygen carriers incorporated with inert supports (MgO and SiO2) exhibit remarkably stable redox reactivity, compared to the pure CuO. Moreover, the redox reactivity of the MgO-incorporated CuO-based oxygen carriers is superior to that of the SiO2-incorporated CuO-based oxygen carriers. It is mainly attributed to the higher Tammann temperature of MgO (1549 K) compared to that of SiO2 (937 K), which more effectively contribute CuO to inhibit particle growth and agglomeration due to sintering. Additionally, the MgO-incorporated CuO-based oxygen carriers prepared via scalable spray-drying method also exhibit the relatively high redox reactivity. It indicates that the spray-dried, synthetic CuO-based oxygen carriers from organometallic precursors possess the potential to be industrialized amplification.

Red Blood Cells-Derived Vesicles for Delivery of Lipophilic Drug Camptothecin.

Recently, cell membrane-derived nanoparticles, particularly of RBCs, have been explored for delivery of hydrophilic solutes of varied size and complexities. So far, these naturally derived nanoparticles show a significant overlap with liposomes in terms of stability, solute encapsulation, and release. Unlike hydrophilic molecules, which are loaded inside the aqueous core, hydrophobic moieties largely partition inside the lipophilic shell, hence fate of these nanocarriers may be different. Since vesicles have more complex membrane architecture (due to natural lipids and additional proteins and glycoproteins), ease of loading hydrophobic drug, its release pattern, and overall particle stability cannot be compared to those of synthetic lipid-based carriers. Therefore, we derived nanovesicles (NVEs) from RBC membrane, loaded with hydrophobic drug camptothecin (CPT) and labeled noncovalently with amphiphilic fluorophore (CM-DiI). Although both CPT and CM-DiI are known to partition inside the membrane, the overall stability of NVEs and composition of membrane proteins, particularly CD47, "marker of self", did not change. Additionally, the developed NVEs were found to be nonphagocytic even in the presence of serum and showed minimal stimulation of macrophages to release cytokines. Further, this system showed slow release but strong retention of CPT and CM-DiI, respectively, over 24 h, hence appropriate for theranostic applications. Also, NVEs were internalized by lung carcinoma cells and possessed slightly higher toxicity than free CPT. When injected intravenously in balb/c mice, these nanovesicles showed higher retention in blood over 48 h and insignificant accumulation in vital organs like heart and kidneys, thus suggesting its potential for in vivo application. We believe that this system has superior stealth and comparable physicochemical properties to synthetic lipid-based nanocarriers; hence, it can be further developed as personalized medicine.

REMOVAL OF PHENOL FROM WATER BY BACILLUS SUBTILIS ONU551 BACTERIA, ADHESIZED ON THE CARRIERS OF DIFFERENT NATURE

Aim. Investigation of the efficiency of removal phenol from water by bacteria Bacillus subtilis ONU551 adhered on the carriers of different nature. Methods. The concentration of phenol in water was determined by extraction-photometric method using 4-aminoantipyrin. The significance of the differences between the mean values of the residual concentration of phenol in water was determined by Student's criterion at a significance level of at least 95% (p ≤ 0.05). Data processing was performed using the program Microsoft Office Excel 2003. Results. The ability of a B. subtilis ONU551 bacterial strain isolated from waste water produced by pharmaceuticals to oxidize phenol was experimentally established. The concentration of phenol in water during its treatment with free cells of the B. subtilis ONU551 bacterial strain in the amount of 5.5×105 CFU/ml for 5 days of exposure decreased from 200.0 to 112.0±5.5 mg/l (by 44% ), reaching maximum on the 15th day – the degree of phenol removal from water was 99-100%. Adhesion of B. subtilis ONU551 bacteria to the surface of natural (zeolite, peat, activated carbon, sand), synthetic (ceramic tubes, fibrous nozzles of the “VIYA” type) of carriers accelerated the removal of phenol from water 1.4–2.5 times , compared to the treatment of water by free bacterial cells. The residual concentration of phenol in water during its treatment with B. subtilis ONU551 bacteria adhered on sand and on “VIYA” type fiber packing decreased for 6 days from 200.0 mg/l to 9.0±0.25 mg/l and 6.0±0.54 mg/l, respectively (by 95–96%) and on the 11th day was at the level of maximum permissible concentration (0.001 mg/l). The degree of removal of phenol from water by B. subtilis ONU551 bacteria adhered on mussel doors, peat and zeolite at the end of cleaning (11 days) ranged from 87% to 99%; and reached 100% – when used as the carriers of activated carbon, ceramic tubes. Conclusion. The use of B. subtilis ONU551 bacteria adhered on natural and synthetic carriers – mussel shutters, peat, sand and fibrous attachment of “VIYA” type ensures 100% removal of phenol from water.

Synthetic hemoglobin-based oxygen carriers are an acceptable alternative for packed red blood cells in normothermic kidney perfusion.

Normothermic machine perfusion presents a novel platform for pretransplant assessment and reconditioning of kidney grafts. Maintaining the metabolic activity of a preserved graft at physiologic levels requires an adequate oxygen supply, typically delivered by crystalloid solutions supplemented with red blood cells. In this study, we explored the feasibility of using a synthetic hemoglobin-based oxygen carrier (HBOC) in human kidney normothermic perfusion. Fourteen discarded human kidneys were perfused for 6hours at a mean temperature of 37°C using a pressure-controlled system. Kidneys were perfused with a perfusion solution supplemented with either HBOC (n=7) or packed red blood cells (PRBC) (n=7) to increase oxygen-carrying capacity. Renal artery resistance, oxygen extraction, metabolic activity, energy stores, and histological features were evaluated. Throughout perfusion, kidneys from both groups exhibited comparable behavior regarding vascular flow (P=.66), oxygen consumption (P=.88), and reconstitution of tissue adenosine triphosphate (P=.057). Lactic acid levels were significantly higher in kidneys perfused with PRBC (P=.007). Histological findings were comparable between groups, and there was no evidence of histological damage caused by the HBOC. This feasibility experiment demonstrates that a HBOC solution can offer a logistically more convenient off-the-shelf alternative to PRBC in normothermic machine perfusion of human kidneys.

Reforming of coal volatiles over ilmenite ore

Chemical-looping combustion is one of the most promising technologies for generating electricity from coal with high CO2 capture. This process burns the fuel with the oxygen from metal oxide particles in the fuel reactor while the depleted oxygen in the metal oxides is compensated for in the air reactor.This study investigated the performance of ilmenite as an oxygen carrier during the steam reforming when actual coal volatiles are used as fuel. Steam reforming experiments on coal volatiles with ilmenite were carried out in a two-stage fixed-bed reactor under various steam conditions. The effect of pre-oxidation and of steam ratios on the conversion reactivity of ilmenite was investigated at 1173 K. The conversion reactivity of ilmenite was greatly enhanced after pre-oxidation, and there was no tar formation when pre-oxidized ilmenite was used. The internal and external porosity of ilmenite also increased after steam reforming of coal volatiles.Ilmenite showed good performance under the various steam conditions. Carbon formation decreased considerably as steam ratios increased. Moreover, the reduced phase FeTiO3 of ilmenite was maintained with the addition of steam, and its reactivity was relatively stable compared with a synthetic iron-based carrier, Fe2O3/Al2O3.