Recovery of Metals from Electronic Waste-Printed Circuit Boards by Ionic Liquids, DESs and Organophosphorous-Based Acid Extraction.

The extraction of metals from waste printed circuit boards (WPCBs) with ionic liquids (ILs), Deep Eutectic Solvents (DESs) and organophosphorous-based acid (Cyanex 272) has been presented. The study was undertaken to assess the effectiveness of the application of the new leaching liquids, and the new method of extraction of metals from the leachate and the solid phase with or without the leaching process. Solvent extraction from the liquid leachate phase has been studied in detail with popular ILs, such as tetraoctylphosphonium bromide, {[P8,8,8,8][Br] and tributyltetradecylphosphonium chloride, [P4,4,4,14][Cl] using Aqueous Biphasic Systems (ABS) method. Trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, [P6,6,6,14][Cyanex272], ([P6,6,6,14][BTMPP]), trihexyltetradecylphosphonium thiocyanate, [P6,6,6,14][SCN], methyltrioctylammonium chloride (Aliquat 336), as well as bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex 272) were also used in the extraction of metals from the leachate. Two DESs (1) {choline chloride + lactic acid, 1:2} and (2) {choline chloride + malonic acid, 1:1} were used in the extraction of metals from the solid phase. The extraction behavior of metals with DESs was compared with that performed with three new bi-functional ILs: didecyldimethylammonium salicylate, [N10,10,1,1][Sal], didecyldimethylammonium bis(2-ethylhexyl) phosphate, [N10,10,1,1][D2EHPA], and didecyldimethylammonium bis(2,4,4-trimethylpentyl) phosphinate, [N10,10,1,1][Cyanex272]. The [P6,6,6,14][Cyanex272]/toluene and (Cyanex 272 + diethyl phosphite ester) mixtures exhibited a high extraction efficiency of about 50-90% for different metal ions from the leachate. High extraction efficiency of about 90-100 wt% with the ABS method using the mixture {[P8,8,8,8][Br], or [P4,4,4,14][Cl] + NaCl + H2O2 + post-leaching liquid phase} was obtained. The DES 2 revealed the efficiency of copper extraction, ECu = 15.8 wt% and silver, EAg = 20.1 wt% at pH = 5 from the solid phase after the thermal pre-treatment and acid leaching. The solid phase extraction efficiency after thermal pre-treatment only was (ECu = 9.6 wt% and EAg = 14.2 wt%). The use of new bi-functional ILs did not improve the efficiency of the extraction of metal ions from the solid phase. Process factors such as solvent concentration, extraction additives, stripping and leaching methods, temperature, pH and liquid/solid as well as organic/water ratios were under control. For all the systems, the selectivity and distribution ratios were described. The proposed extraction processes can represent alternative paths in new technologies for recovering metals from electronic secondary waste.

Fatty acids composition in erythrocyte membranes of athletes after one and after a series of whole body cryostimulation sessions.

Whole body cryotherapy (WBC) is a treatment often used by athletes as part of biological renewal. Despite the large interest in this form therapy there is still a lack of information on the effects of WBC on the concentration of fatty acids in erythrocyte membranes. Our study aimed at comparing the fatty acids (FA) composition of erythrocyte membranes of athletes after one session and after a series of sessions of whole body cryostimulation. In our study small changes in the level of total cholesterol (decrease) were observed 24 h after a single session. After the twelfth session of whole body cryostimulation, the level of saturated fatty acids (SFA), mainly palmitic acid (C16:0) and n-3 fatty acid eicosapentaenoic (EPA, C20:5n-3) increased almost two-times fold in the red blood cell membranes. The level of n-6 polyunsaturated fatty acids (PUFA n-6), mainly gamma-linolenic acid (C18:3n-6) as well as trans fatty acids (elaidic acid) decreased in the erythrocyte membranes from men after a series of session in a cryochamber, when compared to the control sample. The n-3/n-6 FA ratio in the erythrocyte membranes was higher after twelfth session in a cryochamber in comparison to the control sample. The data obtained during our study will be important for further research regarding the biochemistry of lipids in men after sessions of whole body cryostimulation.

The effect of dance therapy on the balance of women over 60 years of age: The influence of dance therapy for the elderly.

Dance therapy is a physical activity that can lead to balance improvement in older adults. The aim of the study was to evaluate the effects of dance therapy on balance and risk of falls in older women. Twenty-four older women (mean age 66.4 years old) attended dance sessions for three months. Pretest/posttests were completed using the Postural Stability Test, the Limits of Stability Test, and the Fall Risk Test M-CTSIB. Results showed the Limits of Stability Test was significantly higher (17.5%) after dance classes. Regular use of dance therapy shows promise in improving balance by increasing the limits of stability.

SYNTHESIS AND ANTIMICROBIAL PROPERTIES OF NEW MANDELATE IONIC LIQUIDS.

Novel mandelate ionic liquids with quartenary ammonium cations were synthesized and characterized. The compounds exhibit antimicrobial activity and the most potent one is of similar efficacy against Gram+ bacteria as its counterpart chloride. On the other hand, the mandelates are much less active against Gram-bacteria and fungi. QSAR models suggest that, with respect to cation, their potency depends on lipophilicity. The synthesized ionic liquids are also quite cytotoxic against mammalian cells.

Rheological properties of erythrocytes in patients infected with Clostridium difficile.

INTRODUCTION: Clostridium difficile infection (CDI) is a bacterial infection of the digestive tract. Acute infections are accompanied by increased risk for venous thromboembolism (VTE). To date, there have been no studies of the rheological properties of blood during the course of digestive tract infections. The aim of our study was to examine the effects of CDI on red blood cell (RBC) rheology, specifically RBC deformability, RBC aggregation, and plasma viscosity. In addition, the activity of glucose 6 phosphate dehydrogenase (G6PD) and acetylcholinesterase (AChE) in RBC was studied. MATERIALS AND METHODS: Our study group included 20 patients with CDI, 20 healthy persons comprised the control group. We examined the effects of CDI on the rheology of RBCs, their deformability and aggregation, using a Laser-assisted Optical Rotational Cell Analyzer (LORCA). Plasma viscosity was determined using a capillary tube plasma viscosymeter. Moreover, we estimated the activity of AChE and G6PD in RBC using spectrophotometric method. RESULTS: A statistically significant increase was found in the aggregation index, viscosity and activity of G6PD whereas the amount of time to reach half of maximum aggregation (t½) and the amplitude of aggregation (AMP) both showed statistically significantly decreases among patients with CDI compared to the control group. We also observed that the Elongation Index (EI) was decreased when shear stress values were low, between 0.3 Pa and 0.58 Pa, whereas EI was increased for shear stress in the range of 1.13-59.97 Pa. These observations were statistically significant. CONCLUSIONS: We report for the first time that acute infection of the gastrointestinal tract with Clostridium difficile is associated with abnormalities in rheological properties of blood, increased serum viscosity as well as increased aggregation of RBCs, which correlated with severity of inflammation. These abnormalities may be an additional mechanism causing increased incidence of VTE in CDI.

Methodology of selecting the reference source for an active noise control system in a car.

At the end of the 20th century, a significant development in digital technologies of signal processing made it possible to apply active noise control methods in new domains. A proper selection of the reference signal source is a main problem in implementing such systems. This paper presents an estimation method based on an indicator of the coherent power level. It also presents a simple system of active noise control in a car, operating according to the proposed method of optimising the positioning of reference sources. This system makes it possible to considerably increase the comfort of work of drivers in various kinds of road transport without a great increase in cost. This is especially significant in the case of trucks and vans. Passive barriers are considerably more expensive in them, which results in a higher level of noise than in passenger cars.

Effects of cold water swimming on blood rheological properties and composition of fatty acids in erythrocyte membranes of untrained older rats.

This is the first report on the effects of a single bout of swimming to exhaustion in cold water on rat erythrocyte deformability, aggregation and fatty acid composition in erythrocyte membranes. The results indicate that there was a significant decrease in body temperature of experimental rats swimming in water at 4 degrees C and 25 degrees C when compared to the control. Erythrocyte aggregation indices did not change after swimming in water at 4 degrees C whereas erythrocyte deformability increased at shear stress 1,13 [Pa] and 15,96 [Pa]. Physical effort performed in water at 4 degrees C when compared to the control group resulted in an increase in monounsaturated and polyunsaturated n-3 fatty acid content in erythrocyte membranes that influenced the increase in their fluidity and permeability even though that of polyunsaturated n-6 fatty acids decreased. Physical effort performed in 25 degrees C water resulted in an increase in saturated fatty acid content and a decrease in all polyunsaturated fatty acids and polyunsaturated n-6 fatty acids when compared to the control group. Swimming of untrained old rats in cold water affected rheological properties oferythrocytes in a negligible way while changes in the fatty acid composition of erythrocyte membranes were more pronounced.

The effect of TCDD dioxin on the rat liver in biochemical and histological assessment.

Eighteen male Wistar rats were divided into 3 groups of 6 animals each. Two groups received different intraperitoneal doses of TCDD (0.75 and 8 microg) in DMSO solution and the third group (control) received only DMSO on days 0, 7 and 14. On day 21 the animals were sacrificed, and then blood tests, pathological examination and CYP1A1 activity measurement were performed. In rats that received a high dose of dioxin (8 microg) hepatic lobules revealed parenchymal degeneration and vacuolization of hepatocytes was observed, and also an increased CYP reaction was found in central parts of lobules, around the central vein. The reaction in control and low dose groups was weak. The resorufin level was significantly (P < 0.05) higher in the group receiving a low dose of dioxin as compared to the control group. The study confirmed that TCDD damages the rat liver in a dose-dependent manner. Administration of high TCDD doses causing major liver damage also damaged CYP1A1 (based on higher resorufin levels in epiluminescence). TCDD activates CYP1A1, which was confirmed by increased immunohistochemical reactivity of central areas ofhepatic lobules.

Ectopic bone formation after treatment with colchicine.

We followed changes occurring within bone tissue and marrow cells during the process of colchicine-induced ectopic bone development and its resorption inside the marrow cavity of the rat tibia. To stimulate ectopic bone formation male Wistar rats were i.p injected with 0.5 or 1 mg/kg b.w. of colchicine or with a 100 microg intra-bone injection. Not all subjects responded to colchicine with ectopic bone formation in the marrow cavity, even among individuals belonging to the same strain. The kind ofresponse in a given animal depended on the dose and site of colchicine administration. During 10 days of the experiment an increase in the occurrence of micronuclei in the polychromatic erythrocytes residing in the bone marrow (even 40-fold) was observed, indicating high genotoxicity of colchicine (at a dose of 1 mg/kg b.w. i.p. or 100 microg intra-bone injection). An increase in the frequency of emperipolesis in megakaryocytes between the 4th and 8th days of the experiment was caused by the toxic action of colchicine and may indicate the labilisation of cell membranes and microtubule depolymerisation.

Red blood cell rheology in patients with chronic venous disease (CVD).

Rheological studies concerning aggregation and elongation of erythrocytes were carried out in 21 patients (mean age 56 years) with chronic venous disease (CVD) and 10 (mean age 45 years) healthy control subjects, with the use of a LORCA device. Higher values of parameters characterizing both erythrocyte elongation (EI) and aggregation (gammathr) in non-control patients than in the control group were found. These values differed significantly ranging from 1.13 to 8.23 Pa for the shear stress and gammathr in patients--432.14, in relation to the control group--166.5. It was proposed, that the increase in deformability may constitute a compensatory mechanism in subjects with chronic venous disease, due to increased resistance in their microcirculation.

Effects of dance movement therapy on the rheological properties of blood in elderly women.

OBJECTIVE: The aim of this study was to analyse the effects of dance movement therapy exercises (DMT) on the rheological properties of blood in elderly women. METHODS: The study encompassed group of women (mean aged: 67 years), who were subjected to three-month dance movement therapy programme (n = 20). Blood samples from all the women were examined for their haematological, rheological, and biochemical parameters both prior to the study and three months thereafter. RESULTS: DMT did not cause statistically significant differences in the number of erythrocytes, thrombocytes, leukocytes and the haematocrit value. DMT affected the rheological parameters of the blood in elderly women, improving the erythrocyte deformability at the lowest shear stress value and reducing the half-time of the total aggregation. Plasma viscosity and concentration of fibrinogen did not change after dance therapy. CONCLUSIONS: DMT modulate rheological properties of blood of older women. The results of this study suggest that physical exercise program for older women can prevent unfavorable age-related changes. Some indicators such as the haematological parameters, plasma viscosity and fibrinogen level were not affected by DMT in older women, suggesting the maintenance of homeostasis.

Effect of whole-body cryotherapy on the rheological parameters of blood in older women with spondyloarthrosis.

BACKGROUND: Cryotherapy is a physiotherapy method used to treat back pain in older persons. OBJECTIVE: This study aims to evaluate the changes in the rheological parameters of blood in older women with spondyloarthrosis, who underwent whole-body cryotherapy. METHODS: The experimental group comprised 69 older women with lumbar spondyloarthrosis, aged between 65 and 70 years. Due to the methodology of the procedure, the experimental group was randomly divided into three groups. Each group underwent two weeks of different types of physiotherapy: only whole-body cryotherapy (22 women); only kinesitherapy (23 women); and both cryotherapy and kinesitherapy (24 women). The control group comprised 25 women who did not undergo any form of therapy. The evaluation of the rheological properties of the blood encompassed measurements of the plasma viscosity, the erythrocyte elongation and aggregation indices, and the level of fibrinogen. RESULTS: The conducted rheological tests revealed a significant decrease in the erythrocyte elasticity and aggregation indices only in the group of women who had undergone both whole-body cryotherapy and kinesitherapy. CONCLUSIONS: Applying whole-body cryotherapy to older women with spondyloarthrosis decreases the elasticity of erythrocytes and, despite favourable changes in the aggregation parameters, problems with perfusion may still appear. For this reason, the benefit of using whole-body cryotherapy in these persons is debatable.

Effects of different rehabilitation models on erythrocyte deformability and nitrite plus nitrate as end-products of nitric oxide levels in elderly women.

AIM: The aim of the present study was to analyze the effects of two rehabilitation protocols, dance movement therapy exercises (DMT) and general rehabilitation exercises (GRE), on erythrocyte deformability and plasma levels of nitrite plus nitrate as end products of nitric oxide (NOx) in elderly women. METHODS: The study included 39 women aged 61-82 years, subjected to either GRE (n = 20) or DMT (n = 19). Women were subjected to 5-months programs of GRE and DMT, with each session lasting no longer than 45-50 min, and the intensity of exercising corresponding to no more than 40-60% of heart rate reserve. Plasma levels of NOx were determined spectrophotometrically before and at the end of the intervention. RESULTS: A significant increase in the total nitrate/nitrite concentration from 1.341 µmol/L to 1.590 µmol/L (7.3%) was observed in women subjected to the DMT rehabilitation program. Furthermore, an increase in erythrocyte deformability was observed in this group at shear stress 0.30. No significant difference was found between the pre- and post-rehabilitation NOx levels of women participating in the GRE program. CONCLUSIONS: Participation in DMT rehabilitation program might be reflected by an increase in plasma NOx levels and an improvement of erythrocyte deformability at lesser shear stress, and thus could potentially result in better vascular function. DMT should be offered to older adults, especially to persons who do not find conventional forms of rehabilitation as attractive, as they might refrain from physical activity and suffer from a faster decline in nitric oxide production. Geriatr Gerontol Int 2017; 17: 2479-2484.

Ectopic bone formation by gel-derived bioactive glass-poly-L-lactide-co-glycolide composites in a rabbit muscle model.

In this study we aimed to assess the in vivo osteoinductive properties of two composite scaffolds made of PLGA (poly-L-lactide-co-glycolide) and two types of gel-derived bioactive glasses, namely a high silica S2 bioactive glass (S2-PLGA composites) or high lime A2 bioactive glass (A2-PLGA composites). To achieve that, the potential of the composites to induce ectopic bone formation in a rabbit muscle has been examined along with the control PLGA scaffold. Cylinder-like scaffolds of 7 × 3 mm (width × height) were implanted into pouches created in the latissimus dorsi muscle of 18 New Zealand rabbits. The tissue sections were obtained at 6, 12 or 24 weeks post-surgery (six rabbits per each time point) and stained with hematoxylin-eosin. The process of wound healing, the formation of collagen-rich connective tissue and its transition to cartilage were examined by Sirius red and Alcian blue histological stainings. We also performed immunohistochemical verification of the presence of osteoblast- and osteoclast- like cells in the vicinity of the scaffolds. A typical foreign body reaction and wound healing process was observed for all implanted scaffolds. Osteoblast- and osteoclast-like cells were observed in the vicinity of the scaffolds as determined by the immunohistochemical staining for Osteocalcin, BMP-2 and Cathepsin K. Compared to plain PLGA scaffolds, numerous osteoblast-like cells were observed 12 weeks post implantation near the composites and the scaffolds gradually degraded as bone formation proceeded. S2-PLGA and A2-PLGA composites display osteoinductive properties in vivo. Furthermore, they are more effective at inducing ectopic bone formation in a rabbit muscle compared to plain PLGA. Thus these SBG-PLGA composite scaffolds have potential for clinical applications in dental and/or orthopedic-bone tissue engineering.

Effects of dance therapy on the selected hematological and rheological indicators in older women.

OBJECTIVE: The aim of this study was to analyze the effects of dance therapy on selected hematological and rheological indicators in older women. METHODS: The study included 30 women (aged 71.8±7.4), and the control group comprised of 10 women of corresponding age. Women from the experimental group were subjected to a five-month dance therapy program (three 45-minute sessions per week); women from the control group were not involved in any regular physical activity. Blood samples from all the women were examined for hematological, rheological, and biochemical parameters prior to the study and five months thereafter. RESULTS: The dance therapy program was reflected by a significant improvement of erythrocyte count and hematocrit. Furthermore, the dance therapy resulted in a significant increase in the plasma viscosity, while no significant changes in glucose and fibrinogen levels were noted. CONCLUSIONS: Dance therapy modulates selected hematological parameters of older women; it leads to increase in erythrocyte count and hematocrit level. Dance therapy is reflected by higher plasma viscosity. Concentrations of fibrinogen and glucose are not affected by the dance therapy in older women, suggesting maintenance of homeostasis. Those findings advocate implementation of dance therapy programs in older women.

Rheological properties of erythrocytes in patients suffering from erysipelas. Examination with LORCA device.

The rheological properties of erythrocytes: elongation and the aggregation, as well as basic peripheral blood parameters: RBC number, hematocrit, MCV, MCH, MCHC reticulocytes, fibrinogen level, ESR, and glucose level were studied in a group of erysipelas patients. The concentration of malonyl dialdehyde (MDA) in erythrocytes was also measured, as an indicator of oxidative stress exerted. The study involved 18 erysipelas patients and 18 healthy subjects. The rheological properties and the aggregation of erythrocytes were studied with the use of a LORCA instrument (Laser-assisted Optical Rotational Cell Analyser). Differences were found in elongation index (EI) between the blood control (C) and patients (P), with an increase of this value only at 0.58 Pa shear stress and at 1.13 Pa shear stress. Upstroke were used as the indexes of RBC deformability, and the following aggregation parameters: intensity of light scattering in the prior disaggregation (Isc dis) - C - 43.0 au (arbitrary units), P - 44.8 au, time when cells are round and not aggregated (Isc top) - C - 51.6 au, P - 49.3 au, the amplitude of aggregation, the difference between Isc max and Isc min (AMP) - C - 39.9 au, P - 28.7 au, aggregation index (AI) - C - 64.6%, P - 70.0%, time for reach one half of the maximum aggregation (t(1/2)) - C - 2.0 s, P - 1.5 s, threshold shear stress, the lowest force that breaks the aggregation formed (Y(thr)) in P exceed 170% control group were measured. A decrease in the elasticity of erythrocytes in erysipelas patients was associated with the simultaneous increase of MDA - C - 0.08 nM/mgHb, P - 0.11 nM/mgHb content in the membranes of red blood cells. Basic peripheral blood parameters studied in patients with erysipelas did not differ significantly from the control group except for WBC, fibrinogen (C - 3.8 g/l, P - 7.8 g/l), and ESR (C - 6.1 mm/h, P - 45.4 mm/h) which were significantly higher.

[Red cell system and selected red cell enzymes in men occupationally exposed to mercury vapours]. / Uklad czerwonokrwinkowy i wybrane enzymy erytrocyta u osób zawodowo narazonych na pary rteci.

Determination of erythrocyte number and their indices and enzymatic activity of: glucose-6-phosphate dehydrogenase (G-6PD), superoxide dismutase (SOD), acetylcholinesterase (AchE), glutathione reductase (GR) and hexokinase (Hx) in peripheral blood erythrocytes of workers chronically exposed to mercury vapours during the production of chloride (the mercuric electrolysis method). The studied workers were equipment operators, electricians and electrolysis maintenance men at the chloride production department using the mercuric electrolysis method. The study involved 46 men, aged 21 to 56, (x = 39 +/- 10.4) exposed to mercury vapours for the period from 7 months to 32 years (x = 14.7+/-10.8), working in a three shift system, for 8 hours a day. Smokers constituted 50% of the studied group (23 men). Urine mercury concentrations of workers exposed to mercury vapours were in the range from 10 to 215 microg/dm3 (x = 81,4 +/- 72,9) and in blood in range 4 do 72 microg/dm3 (x=16.3 +/- 15,0). Controls were 46 men aged 20-54, (x=33.6 +/- 9.8), workers and voluntary blood donors, who never experienced occupational exposure to mercury vapours or other chemicals, and to physical agents. The percentage of smokers in the control group was 34.7% (16 men). Basic haematological determinations (hematocrit - Hct, Hb concentration, erythrocyte number in mm3 of blood, mean red cell hemoglobin concentration (MCHC), mean red cell volume (MCV) and enzymatic studies (activity of G-6PD, SOD, AchE, GR, Hx) in peripheral blood samples obtained from workers and controls were performed. Hematological parameters of the peripheral blood were determined using AVL 808 hematological counter, following the manufacturer's instructions. Activity of the studied enzymes was estimated by the spectrophotometric method described by Beutler, following the recommendations of the International Committee for Standardisation in Hematology. Values of Ht were higher in all the subgroups exposed to Hg workers (divided according to duration of exposure or urine mercury concentrations) in comparison to the control group. The erythrocyte number in mm3 of peripheral blood was also higher in the exposed workers group than in controls. MCHC in the total group exposed to mercury vapours was lower than in the controls. In the subgroup exposed to mercury vapours for < 10 years, the value of this parameter was lower than in the control group; whereas in the subgroups separated in respect to mercury concentration in the urine, it was lower only in workers showing the highest urine concentration of this metal. In workers exposed to mercury vapours, MCV index values were lower than in the controls. In the subgroups of workers who smoked and those who did not smoke, they were also lower than in the controls; whereas in the group of the longest exposed workers from 21 to 35 years, it was found to be higher than in controls. The activity of G6PD was lower in the group of subjects occupationally exposed to mercury vapours than in the control group - 5.60 +/- 1.60 and 7.41 +/- 0.43 IU/gHb respectively. When comparing the subgroups of smokers and non-smokers with the controls, workers showed lower G6PD activity than in the matching control subgroups - 6.24 +/- 1.97 and 7.44 +/-0.22 IU/gHb in the subgroups of smokers and 4.97 +/- 0.72 and 7.38 +/- 0.18 IU/gHb in non-smokers respectively. Erythrocyte G6PD activity was lower in all studied groups separated in respect to exposure time - 5.54 +/- 1.75, 6.02 +/- 2.05 and 5.54 +/- 1.05 IU/gHb respectively. The same pattern of changes was observed in the subgroups separated in respect to mercury concentration in the urine compared to the controls. The lowest enzyme activity was found in the subgroups showing the highest mercury concentration in the urine wnen compared with the subgroup with the lowest urine concentration of this metal - 5.19 +/- 1.50 and 6.00 +/- 1.84 IU/gHb respectively SOD activity in the group of workers exposed to mercury was lower compared to the controls - 2289.97 +/- 122.31 and 2418.03 +/- 60.28 IU/gHb respectively. The smoking and non-smoking workers showed respective SOD activities on - 2305.43 +/- 102.75 and 2274.50 +/- 124.5 IU/gHb; whereas in the matching subgroup of controls - 2452.11 +/- 88.72 and 2382.09 +/- 91.22 IU/gHb, respectively. The activity of this enzyme in all investigated groups selected in respect to length of employment, revealed lower values when compared with the controls - 2271.20 +/- 115.23 in the group with under 10 years of exposure, 2335.11 +/-167.71 IU/gHb in those exposed for 11-20 years, and 2290.40 +/- 26.12 IU/gHb in the subgroup exposed for the longest period of time. Similar changes were observed in the activity of this enzyme in the subgroups separated in respect to mercury concentration in the urine when SOD activity was compared with the controls. The AchE activity was higher in the group exposed to mercury vapours compared to the controls and the respective values were - 50.22 +/- 14.44 and 36.87 +/- 2.92 IU/gHb. In the subgroups separated in respect to length of exposure, the activity of this enzyme was statistically significantly higher than in the control group. The GR activity levels were lower in the exposed group - 8.01 +/-2.54 IU/gHb, compared to the controls - 10.24 +/- 1.24 IU/gHb. In the subgroups of smokers and non-smokers, GR activity was lower, 8.48 +/- 2.37 and 7.54 +/- 2.68 IU/gHb, compared to smokers and non-smokers in the control group, 10.26 +/- 1.01 and 10.16 +/- 1.03 IU/gHb, respectively. The GR activity was also statistically significantly lower in all groups separated in respect to duration of exposure, with the values of 8.56 +/-2.39, 8.26 +/- 2.38, 7.06 +/- 2.75 IU/gHb, respectively in subject groups and 10.24 +/- 1.35 in the control group. Similar changes were noticed in the subgroup separated in respect to mercury concentration in the urine. The Hx activity was lower in the group exposed to mercury vapours - 1.08 +/-0.11. compared with the controls - 1.21 +/- 0.16 IU/gHb. The enzyme activity showed a similar pattern in the subgroups separated in respect to duration of exposure when they were compared with the control group. Exposure to mercury vapours present changes in the red blood cells, manifested by increased (when compared with the control group), number of erythrocytes in peripheral and decreased mean cell volume and mean cell hemoglobin concentration values, as well as changes in the metabolic processes occurring in the erythrocytes. In subjects exposed to mercury vapours some metabolic processes may be additionally modified by addiction to cigarette smoking.

Formation of protoporphyrin IX from carboxylic- and amino-derivatives of 5-aminolevulinic acid.

BACKGROUND: Stability of ALA is an important factor for photodynamic therapy (PDT). The dimerization of ALA to pyrazines takes place via the amine group. It is, therefore, to be expected that blocking this group by addition of a formyl group should result in a more stable compound. METHODS: The ability of a new N-formyl derivative of ALA (N-f-ALA) to form protoporphyrin IX (PPIX) was compared with that of ALA and three of its ester (methyl, butyl and hexyl) derivatives. Dark toxicity of the compounds was measured using MTT assay. Formation of PPIX was measured by fluorescence spectroscopy. RESULTS AND CONCLUSIONS: N-f-ALA showed an outstanding stability in water solutions even at pH 7. However, it induced no PPIX neither in WiDr cells in vitro, nor in mouse skin in vivo. A probable reason is lack of an enzyme that can cleave the bond between the formyl group and ALA. Thus, steric hindrance may prevent processing of the compound into porphobilinogen. N-f-ALA did not inhibit PpIX formation from ALA and is unable to enter the heme cycle. Generation of ALA from its derivatives, therefore, seems to be an essential step in PPIX synthesis.

Synthesis of optically active trans 4-cyclohexyl-L-proline as an intermediate product in the preparation of fosinopril.

A nine-step synthesis of trans 4-cyclohexyl-L-proline has been developed on a laboratory scale. The product is an intermediate in the preparation of fosinopril--an effective hypotensive drug. The total yield of the synthesis was 25%. The final product was 99.7% pure. Analytical methods were developed for each step of the synthesis (HPLC, TLC, IR, 1H-NMR, 13C-NMR, GC-MS, [alpha]D).