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1.
J Neuroeng Rehabil ; 20(1): 51, 2023 04 25.
Article in English | MEDLINE | ID: mdl-37098582

ABSTRACT

BACKGROUND: Traumatic brain injury (TBI) is a leading cause of disabilities resulting from cognitive and neurological deficits, as well as psychological disorders. Only recently, preclinical research on electrical stimulation methods as a potential treatment of TBI sequelae has gained more traction. However, the underlying mechanisms of the anticipated improvements induced by these methods are still not fully understood. It remains unclear in which stage after TBI they are best applied to optimize the therapeutic outcome, preferably with persisting effects. Studies with animal models address these questions and investigate beneficial long- and short-term changes mediated by these novel modalities. METHODS: In this review, we present the state-of-the-art in preclinical research on electrical stimulation methods used to treat TBI sequelae. We analyze publications on the most commonly used electrical stimulation methods, namely transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS) and vagus nerve stimulation (VNS), that aim to treat disabilities caused by TBI. We discuss applied stimulation parameters, such as the amplitude, frequency, and length of stimulation, as well as stimulation time frames, specifically the onset of stimulation, how often stimulation sessions were repeated and the total length of the treatment. These parameters are then analyzed in the context of injury severity, the disability under investigation and the stimulated location, and the resulting therapeutic effects are compared. We provide a comprehensive and critical review and discuss directions for future research. RESULTS AND CONCLUSION: We find that the parameters used in studies on each of these stimulation methods vary widely, making it difficult to draw direct comparisons between stimulation protocols and therapeutic outcome. Persisting beneficial effects and adverse consequences of electrical simulation are rarely investigated, leaving many questions about their suitability for clinical applications. Nevertheless, we conclude that the stimulation methods discussed here show promising results that could be further supported by additional research in this field.


Subject(s)
Brain Injuries, Traumatic , Transcranial Direct Current Stimulation , Animals , Transcranial Direct Current Stimulation/methods , Brain Injuries, Traumatic/therapy , Brain Injuries, Traumatic/complications , Transcranial Magnetic Stimulation/methods , Electric Stimulation
2.
Sci Rep ; 13(1): 3138, 2023 02 23.
Article in English | MEDLINE | ID: mdl-36823232

ABSTRACT

Canine drug-resistant epilepsy is a prevailing issue in veterinary neurology. Alternative or additional treatment with cannabinoids is showing promising results in seizure management. A crucial component of the endocannabinoid system, cannabinoid receptor type 1 (CB1R), is heavily involved in the control of neurotransmitter release. Knowledge of its distribution in the epileptic brain would serve a better understanding of disease pathology and application of cannabinoids in dogs with epilepsy. CB1R distribution was assessed in sub-regions of hippocampus of dogs with idiopathic epilepsy, structural epilepsy and without cerebral pathology. In dogs with idiopathic epilepsy, significantly decreased CB1R expression compared to control animals was observed in CA1. In dogs with structural epilepsy, a significant increase in CB1R signal intensity in comparison to controls was observed. CB1R expression was higher in the structural group as compared to the idiopathic. Double immunofluorescence showed co-localization between CB1R and an astrocytic marker in about 50% of cells, regardless of the diagnosis. In summary, CB1R expression in canine hippocampus undergoes modification by the epileptic process and the direction of this change depends on the etiology of the disease. The distinct disease-associated CB1R expression needs to be considered in new treatment development for dogs with epilepsy.


Subject(s)
Cannabinoids , Epilepsy , Dogs , Animals , Epilepsy/veterinary , Epilepsy/metabolism , Seizures/metabolism , Cannabinoids/metabolism , Hippocampus/metabolism , Receptors, Cannabinoid/metabolism
3.
Sci Rep ; 9(1): 15128, 2019 10 22.
Article in English | MEDLINE | ID: mdl-31641151

ABSTRACT

Enterotoxin-based adjuvants including cholera toxin and heat-labile toxin (LT) are powerful manipulators of mucosal immunity; however, past clinical trials identified unacceptable neurological toxicity when LT or mutant AB5 adjuvant proteins were added to intranasal vaccines. Here, we examined the isolated enzymatic A1 domain of LT (LTA1) for intranasal safety and efficacy in combination with influenza (flu) vaccination. LTA1-treated mice exhibited no neurotoxicity, as measured by olfactory system testing and H&E staining of nasal tissue in contrast with cholera toxin. In vaccination studies, intranasal LTA1 enhanced immune responses to inactivated virus antigen and subsequent protection against H1N1 flu challenge in mice (8-week or 24-months). In addition, lung H1N1 viral titers post-challenge correlated to serum antibody responses; however, enhanced protection was also observed in µMT mice lacking B-cells while activation and recruitment of CD4 T-cells into the lung was apparent. Thus, we report that LTA1 protein is a novel, safe and effective enterotoxin adjuvant that improves protection of an intranasal flu vaccination by a mechanism that does not appear to require B-cells.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Aging/immunology , B-Lymphocytes/immunology , Enterotoxins/administration & dosage , Lymphocyte Depletion , Orthomyxoviridae Infections/immunology , Orthomyxoviridae Infections/prevention & control , Adjuvants, Immunologic/pharmacology , Administration, Intranasal , Animals , Antibodies/blood , Antibody Formation/drug effects , B-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , Dose-Response Relationship, Immunologic , Enterotoxins/immunology , Enterotoxins/toxicity , Female , Immunity, Mucosal/drug effects , Immunization , Inflammation/pathology , Influenza A Virus, H1N1 Subtype/immunology , Lung/virology , Lymphocyte Activation/drug effects , Mast Cells/drug effects , Mast Cells/pathology , Mice, Inbred C57BL , Orthomyxoviridae Infections/blood , Orthomyxoviridae Infections/virology
4.
Drug Alcohol Depend ; 198: 34-38, 2019 05 01.
Article in English | MEDLINE | ID: mdl-30877955

ABSTRACT

BACKGROUND: Interoception may contribute to substance use disorder as it relates to the body's experience of substance use or withdrawal. However, only a few studies have directly investigated associations between interoception and alcohol use. The objective of this study was to compare individuals with alcohol use disorder (AUD) and healthy controls on interoceptive sensibility and accuracy. METHODS: The sample was comprised of two groups: individuals meeting criteria for AUD (N = 114) and healthy controls (N = 110) not meeting criteria for AUD. Interoceptive sensibility was assessed with a self-report measure (the Private Body Consciousness subscale) and interoceptive accuracy - with a behavioral measure (the Schandry test). In addition, associations between interoception and other well-recognized correlates of AUD (sleep problems, depressive and anxiety symptoms, impulsivity) were tested. Barratt's Impulsiveness Scale, Brief Symptom Inventory, and Athens Insomnia Scale were utilized to assess psychopathological symptoms as covariates. RESULTS: When controlling for level of anxiety, sleep problems, age, sex and education, individuals with AUD scored significantly higher on self-reported interoceptive sensibility and lower on interoceptive accuracy in comparison to healthy controls. Higher interoceptive sensibility was associated with more severe sleep problems and anxiety symptoms. CONCLUSIONS: These results have to be treated as preliminary and need to be replicated; however, findings indicate that interoception may present a novel therapeutic target for treatment of AUD.


Subject(s)
Alcoholism/psychology , Anxiety/psychology , Interoception , Sleep Initiation and Maintenance Disorders/psychology , Adult , Cross-Sectional Studies , Female , Humans , Male , Psychopathology , Self Report , Sleep , Young Adult
5.
J Phys Chem A ; 122(39): 7894-7909, 2018 Oct 04.
Article in English | MEDLINE | ID: mdl-30200758

ABSTRACT

Guaiacol or 2-methoxy phenol is one of the main primary tars produced during lignin pyrolysis. Tar conversion in the gas phase influences the production of gaseous and condensable products, and is also responsible for PAH and soot formation during biomass and bio-oil gasification or combustion. Guaiacol pyrolysis and oxidation under stoichiometric conditions were studied in a jet stirred reactor between 623 and 923 K for a residence time of 2 s and under a pressure of 800 Torr (106.7 kPa). Speciation was obtained thanks to online gas chromatography using flame ionization detection and mass spectrometry and allowed the quantification of 22 species in pyrolysis and 42 species in oxidation. Decomposition of guaiacol starts at 650 K, and a conversion degree of 50% is obtained at about 785 K in pyrolysis and 765 K in oxidation. The main products of reaction are pyrocatechol o-HOC6H4OH, o-hydroxybenzaldehyde, methylcatechols, and light products, such as methane, carbon monoxide, ethylene, and hydrogen. A detailed kinetic model based on a combustion model for light aromatics and anisole has been extended to guaiacol. Thermochemical data of guaiacol and main products were calculated theoretically at the CBS-QB3 level of theory. The model predicts well the conversion of guaiacol and the formation of the main products. Guaiacol decomposes mainly through a unimolecular O-C bond breaking to hydroxy phenoxy and methyl radicals in both pyrolysis and oxidation, but H atom abstractions are also of importance in the low temperature range of the study. The unimolecular mechanism leads mainly to pyrocatechol and methylcatechols, whereas the chain radical mechanism is responsible for the formation of hydroxybenzaldehyde. As for anisole but in a much lower extent, an early formation of benzene and soot precursors is observed.

6.
J Physiol Pharmacol ; 69(6)2018 Dec.
Article in English | MEDLINE | ID: mdl-30898987

ABSTRACT

Pullulan and chitosan are biocompatible polysaccharides obtained from natural sources with many biomedical applications. Cationically modified polymers, such as chitosan and pullulan after covalent attachment of glycidyltrimethylammonium chloride (GTMAC), showed beneficial biological properties. In the present study, it was clearly demonstrated and confirmed that both cationically modified polysaccharides (chitosan-GTMAC and pullulan-GTMAC) have the antiatherosclerotic potential by inhibition of atherosclerotic plaque development and controlling the expression of genes involved in lipid metabolism. It has also been shown that the cationically modified chitosan (HTCC) at a dose of 200 mg/kg b.w./day in male apoE-knockout mice acted as hypolipidaemic agent. It was observed that a statistically significant decrease in low-density lipoprotein (LDL) cholesterol level by 32% occurred under the influence of HTCC at a dose of 200 mg/kg b.w./day after 16 weeks of the experiment compared to the control group of apoE(-/-) mice. Moreover, under the influence of cationically modified chitosan administered orally to female apoE-knockout mice at a dose of 300 mg/kg b.w./day for 18 weeks a statistically significant reduction by 33% in the area of atherosclerotic plaque was observed compared to the control group, i.e., apoE-knockout mice whose diet was not supplemented with the cationically modified polysaccharide. Current in vivo studies connected with cationically modified pullulan showed a statistically significant 22% reduction of the area of atherosclerotic plaque in the apoE(-/-) mice fed with a feed containing Pull-GTMAC at a dose of 500 mg/kg b.w./day for 18 weeks in comparison to the control group of apoE-knockout mice. In the in vitro studies it was also shown that cationically modified chitosan acted therapeutically by reduction of the level of the expression of human 3-hydroxy-3-methylglutaryl-CoA reductase (human HMG-CoAR) after 24 hours of incubation with HepG2 cells. However, cationically modified pullulan did not show this effect in the experiment on HepG2 cell line. On the other hand, Pull-GTMAC caused a statistically significant increase in insulin induced gene 1 (INSIG1) expression and increase in mRNA level of LDL receptor in brown fat tissue of female apoE-knockout mice after oral administration with feed at a dose of 300 mg/kg b.w./day for 18 weeks in comparison to the control group of apoE(-/-) mice, that was crearly demonstrated the effect of cationically modified pullulan on the expression of lipid metabolism genes in in vivo conditions. In the present article we have shown for first time that cationically modified pullulan and chitosan have some similarities in their antiatherogenic action but there are also some minor differences in mechanism of their effect on lipid metabolism.


Subject(s)
Atherosclerosis/drug therapy , Biocompatible Materials/pharmacology , Chitosan/pharmacology , Glucans/pharmacology , Plaque, Atherosclerotic/drug therapy , Polysaccharides/pharmacology , Animals , Apolipoproteins E/metabolism , Atherosclerosis/metabolism , Female , Gene Expression/drug effects , Hep G2 Cells , Humans , Hydroxymethylglutaryl CoA Reductases/metabolism , Hypolipidemic Agents/pharmacology , Lipid Metabolism/drug effects , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Plaque, Atherosclerotic/metabolism , Receptors, LDL/metabolism
7.
J Physiol Pharmacol ; 67(5): 739-749, 2016 Oct.
Article in English | MEDLINE | ID: mdl-28011954

ABSTRACT

Pullulan is a biocompatible polysaccharide obtained from black, yeast-like fungus Aureobasidium pullulans. This polymer is used to deliver various substances to the liver because of its specificity for this organ. Pullulan is internalized into hepatocytes in the process of asialoglycoprotein receptor mediated endocytosis. Recently, by reaction with glycidyltrimethylammonium chloride (GTMAC) we have successfully synthesized a cationically-modified pullulan (Pull-GTMAC). Pull-GTMAC exhibits some unique beneficial effects not found for its native counterpart. In this article we have reported for the first time that Pull-GTMAC administered orally to apoE-knockout mice (murine model of atherosclerosis) at a dose of 300 mg/kg b.w./day for 18 weeks showed anti-atherosclerotic activity reducing the area of atherosclerotic plaque. We have also found that Pull-GTMAC at a dose of 300 mg/kg b.w./day increases both the average daily mass of feces and the average number of droppings excreted by apoE(-/-) mouse in relation to the control sample derived from the mice fed with feed without the tested compound. However, the raw fat content in the feces of apoE-knockout mice was decreased in the group fed with the diet containing Pull-GTMAC towards control group of animals. Pull-GTMAC caused also statistically significant increase of mRNA level for LDL receptor in the apoE(-/-) mice liver after administration at a dose of 300 mg/kg/b.w./day for 18 weeks. However, the compound had no impact on lipid profile in serum of the tested mice. What is more, the studies on HepG2 cell line indicated an antiproliferative potential of cationically modified pullulan after 24 hour and 48 hour of incubation with the polysaccharide. In this paper we have shown for first time that cationically modified pullulan has antiatherogenic potential and influences on lipid metabolism.


Subject(s)
Atherosclerosis/metabolism , Epoxy Compounds/pharmacology , Glucans/pharmacology , Lipid Metabolism/drug effects , Quaternary Ammonium Compounds/pharmacology , Animals , Apolipoproteins E/genetics , Atherosclerosis/drug therapy , Cell Survival/drug effects , Epoxy Compounds/chemistry , Epoxy Compounds/therapeutic use , Female , Gene Expression/drug effects , Glucans/chemistry , Glucans/therapeutic use , Hep G2 Cells , Humans , Lipid Metabolism/genetics , Liver/drug effects , Liver/metabolism , Mice, Inbred C57BL , Mice, Knockout , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/therapeutic use , Receptors, LDL/genetics
8.
Int J Mol Med ; 37(3): 807-15, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26820701

ABSTRACT

The purpose of the present study was to investigate the role of WW domain containing oxidoreductase (WWOX) downregulation in biological cancer-related processes in normal (non-malignant) and cancer endometrial cell lines. We created an in vitro model using the normal endometrial cell line, THESC, and 2 endometrial cancer cell lines with varying degrees of differentiation, the Ishikawa (well-differentiated) and the MFE296 (moderately differentiated) cells, in which the WWOX tumor suppressor gene was silenced using Gipz lentiviral shRNA. In this model, we examined the changes in invasiveness via biological assays, such as zymography, migration through a basement membrane, the adhesion of cells to extracellular matrix proteins, anchorage-independent growth and colony formation assay. We also evaluated the correlation between the mRNA expression of the WWOX gene and genes involved in the processes of carcinogenesis, namely catenin beta-1 (CTNNB1) and zinc finger E-box binding homeobox 1 (ZEB1) (gene transcription), cadherin 1 (CDH1) and ezrin (EZR) (cell adhesion), vimentin (VIM) (structural proteins), as well as phosphatase and tensin homolog (PTEN) (tumor suppression) and secreted protein, acidic, cysteine-rich (osteonectin) (SPARC) (SPARC) (cell growth regulation) by RT-qPCR. Downregulation of the WWOX gene in the moderately differentiated MFE296 cell line caused decreased migratory capacity, and a reduction of matrix metalloproteinase-2 (MMP-2) activity. However, these cells grew in semisolid medium and exhibited higher expression of CDH1 and EZR (cell adhesion) and secreted protein, acidic, cysteine-rich (osteonectin) (SPARC) (cell growth regulation). Moreover, in the well-differentiated endometrial cancer (Ishikawa) cell line, WWOX gene silencing resulted in an increased ability of the cells to proliferate indefinitely. Additionally, WWOX regulated changes in adhesion potential in both the normal and cancer cell lines. Our results suggest that the WWOX tumor suppressor gene modulated the processes of cell motility, cell adhesion, gene expression and remodeling in endometrial cell lines.


Subject(s)
Endometrial Neoplasms/metabolism , Endometrial Neoplasms/pathology , Oxidoreductases/metabolism , Tumor Suppressor Proteins/metabolism , Cadherins/metabolism , Cell Line, Tumor , Cytoskeletal Proteins/metabolism , Female , Gene Expression Regulation, Neoplastic/genetics , Gene Expression Regulation, Neoplastic/physiology , Humans , Oxidoreductases/genetics , Tumor Suppressor Proteins/genetics , Vimentin/metabolism , WW Domain-Containing Oxidoreductase , Zinc Finger E-box-Binding Homeobox 1/metabolism , beta Catenin/metabolism
9.
Eur J Vasc Endovasc Surg ; 51(1): 121-6, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26460287

ABSTRACT

OBJECTIVE/BACKGROUND: In light of the methods generally used to assess the risk of venous thromboembolism (VTE), major vascular operations should be regarded as high risk procedures. Nevertheless, no principles for implementing and maintaining thromboprophylaxis have so far been developed. The aim of this study was to determine the frequency and nature of VTE occurrence in patients routinely applying pharmacological thromboprophylaxis following implantation of an aorto-bifemoral prosthesis. METHODS: The prospective non-randomized study included 105 patients with aortoiliac obstruction and 119 patients with abdominal aortic aneurysm (AAA) treated surgically. During hospitalization pharmacological thromboprophylactic procedures were observed. A duplex test was performed on the day before surgery, on the day of discharge, and 30 days after the patients had left the hospital. RESULTS: VTE was detected in 18.1% of the patients with aortoiliac obstruction (9.5% of patients during hospitalization and 8.6% of patients after discharge). VTE was diagnosed in 21.0% of patients with AAA (15.1% of patients during hospitalization and 5.9% of patients after discharge). The incidence of VTE was comparable in both groups, both during hospitalization (p = .51) and in the 30 day period following the end of hospitalization (p = .48). It is advisable that before hospital discharge routine duplex ultrasonography tests should be conducted on the venous systems of all patients who have undergone major vascular operations. CONCLUSIONS: It is likewise advisable to consider whether thromboprophylaxis for vascular patients should be extended beyond their discharge from hospital.


Subject(s)
Anticoagulants/administration & dosage , Aorta, Abdominal/surgery , Aortic Aneurysm, Abdominal/surgery , Arterial Occlusive Diseases/surgery , Blood Vessel Prosthesis Implantation/adverse effects , Fibrinolytic Agents/administration & dosage , Iliac Artery/surgery , Venous Thromboembolism/prevention & control , Aged , Aorta, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/diagnosis , Arterial Occlusive Diseases/diagnosis , Drug Administration Schedule , Factor Xa Inhibitors/administration & dosage , Female , Humans , Iliac Artery/diagnostic imaging , Incidence , Male , Middle Aged , Patient Discharge , Poland/epidemiology , Prospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome , Ultrasonography, Doppler, Duplex , Venous Thromboembolism/diagnosis , Venous Thromboembolism/epidemiology
10.
Chem Commun (Camb) ; 51(36): 7649-52, 2015 May 04.
Article in English | MEDLINE | ID: mdl-25846369

ABSTRACT

A hybrid adsorbent/photocatalyst was obtained and used for the removal of microcystin-LR, a potent toxin, from water via adsorption and photocatalyzed oxidation with singlet oxygen. The combined adsorption/photooxidation processes yielded a 500-fold decrease of the overall MC-LR concentration. The adsorbent/photocatalyst can be easily removed from the reaction system by sedimentation or centrifugation.


Subject(s)
Light , Microcystins/chemistry , Microcystins/isolation & purification , Photochemical Processes/radiation effects , Water/chemistry , Adsorption , Catalysis , Marine Toxins , Molecular Structure , Oxidation-Reduction , Oxygen/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods
11.
Cell Prolif ; 47(6): 516-26, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24961895

ABSTRACT

OBJECTIVES: Properties of cell culture supports obtained from ultrathin multilayer films containing anionic natural polysaccharides (PSacs) and a synthetic polycation were studied. MATERIALS AND METHODS: Supports were prepared via a layer-by-layer (LbL) self-assembly deposition method. Polymers used were: heparin (Hep), chondroitin sulphate (CS), hyaluronic acid (HA), and ι-carrageenan (Car) as polyanions, and diazoresin (DR) as a polycation. PSac layers were crosslinked with DR layers by irradiation with UV light absorbed by DR resin. RESULTS: DR/PSac films are very efficient cell culture growth supports as found from experiments with human mesenchymal stem cells (hMSCs). Irradiation of the films resulted in changing zeta potential of outermost layers of both DR and PSac to more negative values, and in increased film hydrophobicity, as found from the contact angle measurements. Photocrosslinking of the supports led to their increased stability. CONCLUSIONS: The supports allow for obtaining intact cell monolayers faster than when typical polystyrene tissue culture plates are used. Moreover, these monolayers spontaneously detach permitting formation of new cell layers on these surfaces relatively early during culture, compared to cells cultured on commonly used tissue culture plastic.


Subject(s)
Cell Culture Techniques/methods , Mesenchymal Stem Cells/cytology , Polysaccharides/chemistry , Ultraviolet Rays , Azo Compounds/chemical synthesis , Azo Compounds/chemistry , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured , Humans , Hydrophobic and Hydrophilic Interactions , Polyelectrolytes , Polymers/chemistry , Polysaccharides/pharmacology , Silica Gel/chemistry
12.
J Physiol Pharmacol ; 65(3): 341-7, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24930505

ABSTRACT

Chitosan is biocompatible polymer obtained from chitin, the building component of the crustacean shells. In this paper we make an attempt to review the current state of knowledge on some biological effects of chitosan in comparison with those of cationically modified chitosan, N-(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (HTCC) that was recently synthetized by us by covalent attachment of glycidyltrimethylammonium chloride (GTMAC). Biological effects of HTCC and non-modified polymer are very similar. However, HTCC shows some unique beneficial properties which have not been found in its non-modified counterpart. One such example is that HTCC has the ability to bind heparin at physiological pH. HTCC having the degree of substitution almost 63.6% is easily absorbed within 1 hour after oral administration as found in C57BL/6j mice using FITC-labeled polymer. HTCC is distributed to lung, heart, and kidneys. HTCC stimulates and enhances blood platelet aggregation and decreases erythrocyte deformability (RBC). Moreover, HTCC seems to decrease both plasma total cholesterol level and LDL-cholesterol level in apoE-knockout mice fed with a diet containing HTCC. HTCC possibly down-regulates the HMG-CoAR mRNA level after 24 hour incubation with HepG2 cells in vitro.


Subject(s)
Chitosan/analogs & derivatives , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Animals , Chitosan/administration & dosage , Chitosan/chemistry , Chitosan/pharmacology , Humans , Quaternary Ammonium Compounds/administration & dosage
13.
J Microencapsul ; 31(1): 68-76, 2014.
Article in English | MEDLINE | ID: mdl-23834314

ABSTRACT

There is a growing interest in using proteins as therapeutics agents. Unfortunately, they suffer from limited stability and bioavailability. We aimed to develop a new delivery system for proteins. ALP, a model protein, was successfully encapsulated in the physically cross-linked sodium alginate/hydroxypropylcellulose (ALG-HPC) hydrogel microparticles. The obtained objects had regular, spherical shape and a diameter of ∼4 µm, as confirmed by optical microscopy and SEM analysis. The properties of the obtained microbeads could be controlled by temperature and additional coating or crosslinking procedures. The slow, sustained release of ALP in its active form with no initial burst effect was observed for chitosan-coated microspheres at pH = 7.4 and 37 °C. Activity of ALP released from ALG/HPC microspheres was confirmed by the occurance of effectively induced mineralization. SEM and AFM images revealed formation of the interpenetrated three-dimensional network of mineral, originating from the microbeads' surfaces. FTIR and XRD analyses confirmed formation of hydroxyapatite.


Subject(s)
Alginates/chemistry , Alkaline Phosphatase/chemistry , Cellulose/analogs & derivatives , Enzymes, Immobilized/chemistry , Hydrogels/chemistry , Microspheres , Cellulose/chemistry , Delayed-Action Preparations/chemistry , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry
14.
Int J Pharm ; 385(1-2): 163-9, 2010 Jan 29.
Article in English | MEDLINE | ID: mdl-19840839

ABSTRACT

"Smart" (thermosensitive) alginate-hydroxypropylcellulose (Alg/HPC) microbeads for controlled release of heparin were synthesized and the release profiles at various temperatures and for various alginate/HPC compositions were measured. Microbeads of regular spherical shape (ca. 3 microm in diameter) containing efficiently encapsulated heparin were obtained using an emulsification method. The internal structure of the bead was estimated by fluorescence microscopy using dansyl alginate as a labelled component. The microbeads surface structure and morphology were imaged in a dry state using scanning electron microscopy (SEM) and in water using atomic force microscopy (AFM). The microbead surface was shown to be covered by the regular network of pores with a mesh of ca. 30-60 nm. Lower critical solution temperature (LCST) of the Alg/HPC systems was measured spectrophotometrically (cloud point measurements). Heparin release profiles were obtained based on spectrophotometric detection of heparin complex with Azure A. Three-stage sustained release for at least 16 days was observed at 37 degrees C. This was correlated with the size of the pores present at the surface of microbeads. The release profile can be controlled by the temperature and composition of the Alg/HPC microbeads.


Subject(s)
Alginates/chemistry , Cellulose/analogs & derivatives , Drug Carriers , Heparin/chemistry , Microspheres , Cellulose/chemistry , Chemistry, Pharmaceutical , Delayed-Action Preparations , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry , Kinetics , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Microscopy, Fluorescence , Particle Size , Porosity , Solubility , Surface Properties , Technology, Pharmaceutical/methods , Temperature , Water/chemistry
15.
Langmuir ; 25(5): 3255-9, 2009 Mar 03.
Article in English | MEDLINE | ID: mdl-19437787

ABSTRACT

The sequential adsorption of oppositely charged polyelectrolytes called the "layer by layer" technique is a method for formation of ultrathin films with controlled thickness and interfacial properties. Composition of polyelectrolyte solutions, pH, and electrolyte concentration are important parameters governing formation of multilayer films. Since pH is the factor controlling charge of weak polyelectrolytes, the structure of multilayers should be sensitive to its value. In this paper we focused on formation of PE multilayer films composed from weak and strong polyelectrolytes. We used weak, branched polycation polyethyleneimine (PEI, 70 kDa) and strong polyanion poly-4-styrenesulfonate (PSS, 70 kDa) to form films by the layer-by-layer technique on the surface of silicon wafers under two deposition conditions: pH = 6 when PEI was strongly charged and pH = 10.5 when the charge density of PEI was low. Thicknesses of films were measured by single wavelength ellipsometry, and the results were confronted with ones concerning mass of the adsorbed films obtained by quartz crystal microbalance. We found that, depending on pH of the solutions, combination of weakly and strongly charged polyelectrolytes gave either linear or nonmonotonic increase of film thickness with a number of deposited PE layers. We observed a good correlation between multilayer film thickness and adsorbed mass. The atomic force microscopy images of surface topography of PEI/PSS films demonstrated large differences between films deposited at pH = 6 and 10.5. Additionally the cyclic voltamperometry was used to determine the differences in permeability of films formed at various pH conditions.

16.
Exp Clin Endocrinol Diabetes ; 115(3): 179-81, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17427107

ABSTRACT

UNLABELLED: The often CSII treatment complication is local skin infection. The aim of the study was to analyze chosen factors predisposing to this complication. MATERIAL AND METHODS: We observed 40 children aged 1.9-15.6, suffering from diabetes for 0.1-12 and treated by CSII for 0.01-4.4 years in whom HbA1c, BMI, injection site and catheter insertion duration, catheter colonization, skin flora and Staphylococcus aureus carrier state were analyzed. The catheter cultures were prepared with Maki method. The skin and nasal vestibule swab were taken to detect local flora. RESULTS: In the culture of 43 catheters (Maki method) a positive growth (>10 cfu) was detected in 9 (21%), homogeny culture of coagulase-negative staphylococci in 7 and mixed culture (both S.epidermidis and S.aureus) in two cases. Skin inflammation of the injection site was observed in a total of 10 children (25%), in two of whom catheter culture was positive. A statistically significant relation between the presence of bacteria in the catheter and on the skin around the injection site was found. Among the examined parameters, the relation between the catheter colonization and HbA1c, female sex and BMI were observed. CONCLUSIONS: Metabolic control, female sex and BMI influence the development of a skin inflammatory state in patients treated with CSII. S.aureus carrier state has no impact either on catheter colonization or the development of an infection. However, bacteria skin occurrences can predispose to catheter colonization by the strain as well as to developing an inflammation.


Subject(s)
Bacterial Infections/classification , Bacterial Infections/etiology , Diabetes Mellitus, Type 1/drug therapy , Inflammation/etiology , Insulin Infusion Systems/adverse effects , Skin Diseases/microbiology , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Inflammation/epidemiology , Male , Poland , Skin Diseases/etiology
18.
Toxicol In Vitro ; 14(3): 253-63, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10806376

ABSTRACT

The pig is increasingly being used in pharmacological and toxicological studies, and is the species of choice for future research into xenotransplantation, extracorporeal liver support and hepatocyte-based bioartificial liver. However, relatively little is known about xenobiotic-metabolizing enzymes in this species. In the present study, immunoblotting with polyclonal anti-rat and anti-human cytochrome P450 (CYP) antibodies revealed the presence of proteins in pig liver which cross-reacted with anti-human CYP1A2, CYP2D6 and CYP3A4, and with anti-rat CYP2E1 antibodies. Northern blot analysis demonstrated the presence of mRNA which hybridized to cDNA probes for human CYP2D6, CYP2E1 and CYP3A4, and to an oligonucleotide probe for pig CYP3A29. As there is a lack of a good animal model for CYP2D6, the presence of a CYP2D6-related protein in pig liver was of particular interest. Pig hepatocytes also demonstrated CYP2D6 immunoreactive protein, and mRNA hybridizable to a CYP2D6 cDNA probe. We investigated the ability of pig liver microsomes to catalyse dextromethorphan O-demethylation, a widely-used marker enzyme activity for CYP2D6. This enzyme activity demonstrated biphasic kinetics, with a high affinity apparent K(m1)=6.9+/-3.6 microM and V(max1)=10.5+/-6.1nmol/min/nmol CYP. The reaction was sensitive to inhibition by the CYP2D6-selective inhibitors quinidine, quinine, lobeline and norfluoxetine, whereas chemical inhibitors selective for other CYP isoforms failed to affect the reaction. We conclude that dextromethorphan O-demethylation is catalysed by a CYP2D enzyme which is remarkably similar to human CYP2D6, suggesting potential value of the pig as a model for predicting human metabolism of xenobiotics which undergo CYP2D6-dependent biotransformation.


Subject(s)
Cytochrome P-450 CYP2D6/physiology , Dextromethorphan/metabolism , Microsomes, Liver/metabolism , Animals , Blotting, Northern , Blotting, Western , Catalysis , Cells, Cultured , Dealkylation , Female , Male , Swine
19.
Chemosphere ; 39(13): 2249-58, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10576097

ABSTRACT

Photosensitized by poly (sodium styrenesulfonate-co-2-vinylnaphthalene) (PSSS-VN) oxidation of cyanide in an aqueous solution was studied. The reaction was found to occur via photoinduced electron transfer from CN- to the polymeric chromophores. The process leads to formation of NCO-.


Subject(s)
Cyanides/chemistry , Naphthalenes/chemistry , Photosensitizing Agents/chemistry , Polyvinyls/chemistry , Catalysis , Hydrogen-Ion Concentration , Industrial Waste , Kinetics , Light , Oxidation-Reduction , Photochemistry , Solutions , Water/chemistry , Water Purification/methods
20.
Med Dosw Mikrobiol ; 50(1-2): 63-8, 1998.
Article in Polish | MEDLINE | ID: mdl-9857615

ABSTRACT

The aim of the study was a microbiological analysis of pharyngeal swabs obtained from 158 patients with the diagnosis of pharyngitis and purulent exudates from the tonsillar crypts of 10 patients treated for chronic purulent tonsillitis. Beta haemolytic streptococci groups A, B, C and G were isolated from 30% of the patients. The most frequently isolated were Streptococcus pyogenes--12% of patients and Streptococcus group C--10.7%. Other streptococci were isolated less frequently: Streptococcus group B--44%, group G--2.5%. The majority of isolated bacteria belonged to potential pathogenic flora (70% patients). Staphylococcus aureus (37%) and Haemophilus spp. (36%) were isolated most frequently. Other bacteria were isolated in the following sequence: Moraxella catarrhalis--22%, Streptococcus pneumoniae--17% and Gram-negative rods from the Enterobacteriaceae family--6%. One case of Plaut-Vincent tonsillitis was diagnosed. Aerobic and anaerobic bacteria were isolated from purulent exudates from the tonsillar crypts of 10 patients treated for chronic purulent tonsillitis. The isolated anaerobic bacteria belonged to genus of Prevotella, Fusobacterium, Peptostreptococcus and Gemella.


Subject(s)
Bacteria/isolation & purification , Pharyngitis/microbiology , Tonsillitis/microbiology , Chronic Disease , Exudates and Transudates/microbiology , Haemophilus/isolation & purification , Humans , Palatine Tonsil/microbiology , Pharynx/microbiology , Species Specificity , Staphylococcus/isolation & purification , Streptococcus/isolation & purification
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