The aim of our study was to measure granulocyte and monocyte phagocytosis following treatment of ... more The aim of our study was to measure granulocyte and monocyte phagocytosis following treatment of cells with some metabolites of aliphatic alcohols alone and in combination with acetaldehyde. The cells were separated from human peripheral blood prior to determination of phagocytosis of opsonized zymosan particles by granulocytes and monocytes treated individually with metabolites of aliphatic alcohols including formaldehyde, 1-propanal, acetone, 1-butanal, and 2-butanone and in combination with acetaldehyde. The findings revealed that metabolites of aliphatic alcohols inhibited phagocytosis by granulocytes and monocytes in a concentration-dependent manner and when combined with acetaldehyde, they caused a further decrease in phagocytic activity. Due to their additive effects, it is possible that, in combination with acetaldehyde, metabolites of aliphatic alcohols may inhibit phagocytosis at physiologically realistic concentrations in episodic heavy drinkers, thereby contributing to their increased susceptibility to infectious diseases.
In this study we investigate a laboratory scale vacuum membrane distillation system to produce pu... more In this study we investigate a laboratory scale vacuum membrane distillation system to produce pure water from model oil in water emulsion. Experimental determination of liquid entry pressure (LEP) of a commercial Durapore TM GVPH flat sheet membrane using model emulsions in various oil concentrations has been carried out. Two different methods of liquid entry pressure determination – a frequently used, so-called static and a novel dynamic method – have been investigated. In case of static method, LEP value was found to be 2.3 bar. No significant effect of oil content on LEP was detected up to 3200 ppm. In contrast, LEP values determined with dynamic method showed strong dependence on the oil concentration of the feed and decreased from 2.0 bar to a spontaneous wetting at 0.2 bar in the range 0-250 ppm, respectively. Vacuum membrane distillation tests were also performed. The separation performance is evaluated in terms of flux behavior, total organic carbon removal and droplet size...
Different salt solutions such as CH 3 CO 2 K, NH 4 NO 3 , K 2 CO 3 , and CaCl 2 have been examine... more Different salt solutions such as CH 3 CO 2 K, NH 4 NO 3 , K 2 CO 3 , and CaCl 2 have been examined as alternatives for osmotic distillation process concentrating pre-concentrated sour cherry juice. Simplified estimation of mass transfer phenomena has been also performed. Further analytical methods such as total antioxidant activity, and total polyphenolic content using spectrophotometric assays have been also carried out to evaluate the effect of the osmotic distillation treatments on valuable compounds losses of concentrated sour cherry juice.
Sour cherry is one of the most famous and characteristic Hungarian fruit what is also commonly us... more Sour cherry is one of the most famous and characteristic Hungarian fruit what is also commonly used in food production as a colour additive. The sour cherry cultivar, ‘Oblachinska’ was shown to be a rich source of antioxidant compounds, including mainly anthocyanins. Valuable compounds in fruit juice – vitamins, polyphyenols etc. –are heat-sensitive molecules, which should be taken into account during the process of concentration to prevent degradation. Osmotic distillation seems a suitable option to product high quality sour cherry juice because this process does not require high temperature or pressure. Raw juice with approximately 15°Brix was used for the experiment and tried to concentrate up to 60° Brix where the water activity low enough to inhibit the microbiological deterioration. Before and after the process, TPC (total phenolic compounds) and FRAP (ferric reducing antioxidant power) was measured using spectrophotometric methods to determine the effect of the osmotic distil...
Sour cherry is one of the most famous and characteristic Hungarian fruit what is commonly used fo... more Sour cherry is one of the most famous and characteristic Hungarian fruit what is commonly used for in food production as colour additive. Valuable compounds in fruit juice –vitamins, polyphyenols, etc.-are heat and mechanical sensitive molecules and during the concentrate process should have to avoid from degradation. Osmotic distillation seems suitable option to product high quality of sour cherry juice because this process not requires high temperature or pressure. Raw juice with approximately 15°Brix was used for the experiment and tried to concentrate up to 60°Brix where the water activity enough low to inhibit the microbiological effects. Before and after the process TPC (total phenolic compounds) and AC (antioxidant capacity) was measured by spectrophotometric method to determine the effect of the osmotic distillation. Results point out that osmotic distillation is a promising method to make concentrated sour cherry juice while the valuable compounds could avoid the degradation.
In this present work a laboratory scale vacuum membrane distillation system has been applied to p... more In this present work a laboratory scale vacuum membrane distillation system has been applied to produce pure water from oil in water emulsion. Vacuum membrane distillation tests have been performed with various oil concentrations up to 250 ppm. Furthermore liquid entry pressure of pure water and oil emulsions in various concentration using two different methods (static and dynamic) has been also determined using commercial Durapore TM
Membrane emulsifi cation (ME) is a relatively new technique for the highly controlled production ... more Membrane emulsifi cation (ME) is a relatively new technique for the highly controlled production of particulates, which helps to obtain a narrower distribution compared to other emulsifi cation techniques such as homogenizers or ultrasound. Benefi ts of membrane emulsifi cation for food applications include the low shear properties and the uniform size distribution. In this process, the dispersed phase (oil) is pressed through the pores of a microporous membrane directly into the continuous phase (water) fl owing tangentially to the membrane surface. The purpose of the emulsifi cation experimentations was to fi nd and model operating conditions of the operation. In laboratory experiments from conventional, commercial grade sunfl ower oil (dispersed phase) and from distilled water (solid phase), emulsions were prepared. The ceramic tube membrane with nominal pore size of 1.4 μm was used in the experiments (ZrO 2 ). In order to increase the shear-stress near the membrane wall (infl uence the characteristics of the fl ow regime of the continuous phase), a kind of self-fabricated helical-shaped-ribbon reducer was installed inside the tube membrane.
Membrane distillation (MD) is a thermally driven separation process that employs a hydrophobic me... more Membrane distillation (MD) is a thermally driven separation process that employs a hydrophobic membrane as a barrier for the liquid phase, allowing only vapor phase to pass through the membrane pores. Wetting of membrane pores by liquid streams (i.e. the loss of hydrophobic characteristics of membranes) is a crucial issue in MD treatment. This paper is organized into two parts. The first part provides an overview of the theoretical background of wetting phenomenon and guides the reader through the experimental techniques presented in the literature for determining liquid entry pressure (LEP) of MD membranes. In the second part, we provide experimentally measured data on LEP values of some commercially available hollow-fiber and flat-sheet membranes tested in our lab using different MD configurations. The LEP w value of the MD 020 CP 2N hollow-fiber membrane (Microdyn-Nadir GmbH, Wiesbaden, Germany) made of PP is found to be 0.97 bar using direct-contact membrane distillation (DCMD) configuration. The LEP w value of the Durapore TM GVPH flat sheet membrane (Merck Millipore Inc., Billerica, USA) made of PVDF is found to be 2.37±0.025 bar using static measurement technique and 1.90 bar using vacuum MD configuration. We also show that wetted membranes can be successfully regenerated by soaking them in ethanol and removing ethanol with evaporation at elevated temperatures. A novel concept of regeneration procedures applying vacuum have developed and have been proved to be effective for the tested flat sheet modules, however, failed on recovering the hydrophobic characteristics of the PP membrane in the hollow-fiber module.
The purpose of this study was to examine a recent integrated membrane process including microfilt... more The purpose of this study was to examine a recent integrated membrane process including microfiltration, reverse osmosis and osmotic distillation for producing concentrated sage (Salvia fruticosa Miller) extract. Critical and limiting conditions with respect to the flux and transmembrane pressure difference in case of the applied membrane filtration techniques were brought to the light. Regarding the valuable compound retention of the integrated process, total phenolic content, total flavonoid content and antioxidant activity using spectrophotometric assays were determined. Individual phenolic compounds of the initial and concentrated sage extracts and their retention using high-performance liquid chromatography were also determined. Individual phenolic compounds namely apigenin, rutin, hesperetin, luteolin, caffeic acid, p-coumaric, ferulic and rosmarinic acids were identified. The study concluded that sage extract can be successfully concentrated up to 32.4 w/w% by using the suggested integrated membrane process, however, a remarkable valuable compounds loss (30-40%) can be observed during reverse osmosis process in the applied conditions. Contrast, osmotic distillation was able to retain more than 90% the total polyphenol content, total flavonoid content and antioxidant activity and also almost all of the determined individual polyphenols with more than 90% retention.
This is a retrospective review of 26 patients with chronic intractable pain in which dorsal colum... more This is a retrospective review of 26 patients with chronic intractable pain in which dorsal column stimulation was used as a salvage procedure. On follow-up of 12 to 42.7 months, 21 of the patients had diminished narcotic usage. Seventeen patients subjectively rated their pain relief as good to excellent. Another five patients reported some relief of pain. Two-thirds of the patients reported an increase in their ability to perform daily activities such as walking, stair climbing, and time spent sitting. There are still many technical problems that plague this procedure, as evidenced by a very high technical complication rate of lead migration and lead breakage. Whether or not results diminish over long-term follow-up remains to be seen.
Mutation Research/Genetic Toxicology and Environmental Mutagenesis, 2014
Phenothrin, a synthetic pyrethroid compound, is widely used to control agricultural and household... more Phenothrin, a synthetic pyrethroid compound, is widely used to control agricultural and household insects, as well as to eliminate human louse infestation. Toxicity studies on the direct DNA-damaging effect of phenothrin are lacking. We therefore investigated whether phenothrin exposure can lead to increased DNA damage in vitro in human peripheral blood lymphocytes and in human hepatocytes. Genotoxicity was evaluated by means of the comet assay modified with formamidopyrimidine DNA-glycosylase post-treatment for the detection of oxidative base-damage in DNA. We also assessed the cytotoxic potential of this compound by use of combined fluorescence viability staining. Our results show that phenothrin induces statistically significant, dose-dependent DNA damage in the absence of marked cytotoxicity at concentrations higher than 20 µM and 50 µM in human blood peripheral lymphocytes and hepatocytes, respectively. Oxidative DNA damage could also be detected in the two cell types, although this did not reach statistical significance. These findings provide evidence of the DNA-damaging potential of phenothrin and call for additional studies to reveal the genotoxic properties of this pyrethroid. The observations also point at the importance of using caution when considering the use of phenothrin.
The aim of our study was to measure granulocyte and monocyte phagocytosis following treatment of ... more The aim of our study was to measure granulocyte and monocyte phagocytosis following treatment of cells with some metabolites of aliphatic alcohols alone and in combination with acetaldehyde. The cells were separated from human peripheral blood prior to determination of phagocytosis of opsonized zymosan particles by granulocytes and monocytes treated individually with metabolites of aliphatic alcohols including formaldehyde, 1-propanal, acetone, 1-butanal, and 2-butanone and in combination with acetaldehyde. The findings revealed that metabolites of aliphatic alcohols inhibited phagocytosis by granulocytes and monocytes in a concentration-dependent manner and when combined with acetaldehyde, they caused a further decrease in phagocytic activity. Due to their additive effects, it is possible that, in combination with acetaldehyde, metabolites of aliphatic alcohols may inhibit phagocytosis at physiologically realistic concentrations in episodic heavy drinkers, thereby contributing to their increased susceptibility to infectious diseases.
In this study we investigate a laboratory scale vacuum membrane distillation system to produce pu... more In this study we investigate a laboratory scale vacuum membrane distillation system to produce pure water from model oil in water emulsion. Experimental determination of liquid entry pressure (LEP) of a commercial Durapore TM GVPH flat sheet membrane using model emulsions in various oil concentrations has been carried out. Two different methods of liquid entry pressure determination – a frequently used, so-called static and a novel dynamic method – have been investigated. In case of static method, LEP value was found to be 2.3 bar. No significant effect of oil content on LEP was detected up to 3200 ppm. In contrast, LEP values determined with dynamic method showed strong dependence on the oil concentration of the feed and decreased from 2.0 bar to a spontaneous wetting at 0.2 bar in the range 0-250 ppm, respectively. Vacuum membrane distillation tests were also performed. The separation performance is evaluated in terms of flux behavior, total organic carbon removal and droplet size...
Different salt solutions such as CH 3 CO 2 K, NH 4 NO 3 , K 2 CO 3 , and CaCl 2 have been examine... more Different salt solutions such as CH 3 CO 2 K, NH 4 NO 3 , K 2 CO 3 , and CaCl 2 have been examined as alternatives for osmotic distillation process concentrating pre-concentrated sour cherry juice. Simplified estimation of mass transfer phenomena has been also performed. Further analytical methods such as total antioxidant activity, and total polyphenolic content using spectrophotometric assays have been also carried out to evaluate the effect of the osmotic distillation treatments on valuable compounds losses of concentrated sour cherry juice.
Sour cherry is one of the most famous and characteristic Hungarian fruit what is also commonly us... more Sour cherry is one of the most famous and characteristic Hungarian fruit what is also commonly used in food production as a colour additive. The sour cherry cultivar, ‘Oblachinska’ was shown to be a rich source of antioxidant compounds, including mainly anthocyanins. Valuable compounds in fruit juice – vitamins, polyphyenols etc. –are heat-sensitive molecules, which should be taken into account during the process of concentration to prevent degradation. Osmotic distillation seems a suitable option to product high quality sour cherry juice because this process does not require high temperature or pressure. Raw juice with approximately 15°Brix was used for the experiment and tried to concentrate up to 60° Brix where the water activity low enough to inhibit the microbiological deterioration. Before and after the process, TPC (total phenolic compounds) and FRAP (ferric reducing antioxidant power) was measured using spectrophotometric methods to determine the effect of the osmotic distil...
Sour cherry is one of the most famous and characteristic Hungarian fruit what is commonly used fo... more Sour cherry is one of the most famous and characteristic Hungarian fruit what is commonly used for in food production as colour additive. Valuable compounds in fruit juice –vitamins, polyphyenols, etc.-are heat and mechanical sensitive molecules and during the concentrate process should have to avoid from degradation. Osmotic distillation seems suitable option to product high quality of sour cherry juice because this process not requires high temperature or pressure. Raw juice with approximately 15°Brix was used for the experiment and tried to concentrate up to 60°Brix where the water activity enough low to inhibit the microbiological effects. Before and after the process TPC (total phenolic compounds) and AC (antioxidant capacity) was measured by spectrophotometric method to determine the effect of the osmotic distillation. Results point out that osmotic distillation is a promising method to make concentrated sour cherry juice while the valuable compounds could avoid the degradation.
In this present work a laboratory scale vacuum membrane distillation system has been applied to p... more In this present work a laboratory scale vacuum membrane distillation system has been applied to produce pure water from oil in water emulsion. Vacuum membrane distillation tests have been performed with various oil concentrations up to 250 ppm. Furthermore liquid entry pressure of pure water and oil emulsions in various concentration using two different methods (static and dynamic) has been also determined using commercial Durapore TM
Membrane emulsifi cation (ME) is a relatively new technique for the highly controlled production ... more Membrane emulsifi cation (ME) is a relatively new technique for the highly controlled production of particulates, which helps to obtain a narrower distribution compared to other emulsifi cation techniques such as homogenizers or ultrasound. Benefi ts of membrane emulsifi cation for food applications include the low shear properties and the uniform size distribution. In this process, the dispersed phase (oil) is pressed through the pores of a microporous membrane directly into the continuous phase (water) fl owing tangentially to the membrane surface. The purpose of the emulsifi cation experimentations was to fi nd and model operating conditions of the operation. In laboratory experiments from conventional, commercial grade sunfl ower oil (dispersed phase) and from distilled water (solid phase), emulsions were prepared. The ceramic tube membrane with nominal pore size of 1.4 μm was used in the experiments (ZrO 2 ). In order to increase the shear-stress near the membrane wall (infl uence the characteristics of the fl ow regime of the continuous phase), a kind of self-fabricated helical-shaped-ribbon reducer was installed inside the tube membrane.
Membrane distillation (MD) is a thermally driven separation process that employs a hydrophobic me... more Membrane distillation (MD) is a thermally driven separation process that employs a hydrophobic membrane as a barrier for the liquid phase, allowing only vapor phase to pass through the membrane pores. Wetting of membrane pores by liquid streams (i.e. the loss of hydrophobic characteristics of membranes) is a crucial issue in MD treatment. This paper is organized into two parts. The first part provides an overview of the theoretical background of wetting phenomenon and guides the reader through the experimental techniques presented in the literature for determining liquid entry pressure (LEP) of MD membranes. In the second part, we provide experimentally measured data on LEP values of some commercially available hollow-fiber and flat-sheet membranes tested in our lab using different MD configurations. The LEP w value of the MD 020 CP 2N hollow-fiber membrane (Microdyn-Nadir GmbH, Wiesbaden, Germany) made of PP is found to be 0.97 bar using direct-contact membrane distillation (DCMD) configuration. The LEP w value of the Durapore TM GVPH flat sheet membrane (Merck Millipore Inc., Billerica, USA) made of PVDF is found to be 2.37±0.025 bar using static measurement technique and 1.90 bar using vacuum MD configuration. We also show that wetted membranes can be successfully regenerated by soaking them in ethanol and removing ethanol with evaporation at elevated temperatures. A novel concept of regeneration procedures applying vacuum have developed and have been proved to be effective for the tested flat sheet modules, however, failed on recovering the hydrophobic characteristics of the PP membrane in the hollow-fiber module.
The purpose of this study was to examine a recent integrated membrane process including microfilt... more The purpose of this study was to examine a recent integrated membrane process including microfiltration, reverse osmosis and osmotic distillation for producing concentrated sage (Salvia fruticosa Miller) extract. Critical and limiting conditions with respect to the flux and transmembrane pressure difference in case of the applied membrane filtration techniques were brought to the light. Regarding the valuable compound retention of the integrated process, total phenolic content, total flavonoid content and antioxidant activity using spectrophotometric assays were determined. Individual phenolic compounds of the initial and concentrated sage extracts and their retention using high-performance liquid chromatography were also determined. Individual phenolic compounds namely apigenin, rutin, hesperetin, luteolin, caffeic acid, p-coumaric, ferulic and rosmarinic acids were identified. The study concluded that sage extract can be successfully concentrated up to 32.4 w/w% by using the suggested integrated membrane process, however, a remarkable valuable compounds loss (30-40%) can be observed during reverse osmosis process in the applied conditions. Contrast, osmotic distillation was able to retain more than 90% the total polyphenol content, total flavonoid content and antioxidant activity and also almost all of the determined individual polyphenols with more than 90% retention.
This is a retrospective review of 26 patients with chronic intractable pain in which dorsal colum... more This is a retrospective review of 26 patients with chronic intractable pain in which dorsal column stimulation was used as a salvage procedure. On follow-up of 12 to 42.7 months, 21 of the patients had diminished narcotic usage. Seventeen patients subjectively rated their pain relief as good to excellent. Another five patients reported some relief of pain. Two-thirds of the patients reported an increase in their ability to perform daily activities such as walking, stair climbing, and time spent sitting. There are still many technical problems that plague this procedure, as evidenced by a very high technical complication rate of lead migration and lead breakage. Whether or not results diminish over long-term follow-up remains to be seen.
Mutation Research/Genetic Toxicology and Environmental Mutagenesis, 2014
Phenothrin, a synthetic pyrethroid compound, is widely used to control agricultural and household... more Phenothrin, a synthetic pyrethroid compound, is widely used to control agricultural and household insects, as well as to eliminate human louse infestation. Toxicity studies on the direct DNA-damaging effect of phenothrin are lacking. We therefore investigated whether phenothrin exposure can lead to increased DNA damage in vitro in human peripheral blood lymphocytes and in human hepatocytes. Genotoxicity was evaluated by means of the comet assay modified with formamidopyrimidine DNA-glycosylase post-treatment for the detection of oxidative base-damage in DNA. We also assessed the cytotoxic potential of this compound by use of combined fluorescence viability staining. Our results show that phenothrin induces statistically significant, dose-dependent DNA damage in the absence of marked cytotoxicity at concentrations higher than 20 µM and 50 µM in human blood peripheral lymphocytes and hepatocytes, respectively. Oxidative DNA damage could also be detected in the two cell types, although this did not reach statistical significance. These findings provide evidence of the DNA-damaging potential of phenothrin and call for additional studies to reveal the genotoxic properties of this pyrethroid. The observations also point at the importance of using caution when considering the use of phenothrin.
Uploads
Papers by Gabor Racz