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The article discusses issues related to the melting of grey and ductile cast iron in terms of metallurgical quality. The derivative and thermal analysis (DTA) was used to assess this quality. The article presents the results of research carried out in industrial conditions and analysed by the Itaca system. In the paper, the effect of the furnace type, the charge materials and the inoculation process on the parameters characterising the cast iron being melted was analysed. The most important of these are the minimum eutectic temperature (Temin), the liquidus temperature (Tliquidus) and the nucleation rate. The results of the research and calculations are shown in graphs and as dependencies. Some of DTA results were compared to the microstructure analysis results. The article shows that the derivative and thermal analysis is a very effective tool in the assessment of the metallurgical quality of cast iron. It is a very good addition to chemical analysis. Based on the results of the research, it was concluded that a very high correlation exists between the rate of nucleation (DTA) and the number of graphite nuclei (microstructure analysis). Furthermore, it was also found that an improvement in nucleation could be achieved by ensuring a high value of carbon equivalent (CE) and, above all, by conducting the primary and secondary inoculation processes, respectively. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) is often accompanied by lung cancer. In our previous work, it was observed that matrix metalloproteinase-3 and haptoglobin ( HP ) polymorphisms were potential markers of enhanced susceptibility to lung cancer development among male COPD subjects. Here, results are reported on blood serum levels of several proteins involved in iron metabolism, inflammation and the oxidative stress response compared between the same groups of subjects. The blood serum levels of tumor necrosis factor α (TNFα), transferrin, hepcidin, ferritin, soluble transferrin receptor and 8-oxo-2'-deoxyguanosine were compared, as well as total iron-binding capacity (TIBC) and ceruloplasmin ferroxidase activity in two groups of subjects: Male COPD patients (54 subjects) and male COPD patients diagnosed with lung cancer (53 subjects). Statistically significant differences were identified between the two groups in transferrin and TNFα levels, as well as in TIBC; all three parameters were lower in the group consisting of COPD patients diagnosed with lung cancer (P<0.01). It was also revealed that HP genotype 1/2 was concomitant with low transferrin blood level in subjects with COPD; this apparent dependence was absent in the COPD + cancer subjects. The results indicate a role of iron metabolism in the susceptibility to lung cancer in COPD-affected subjects. They also emphasize the importance of individual capacity for an effective response to oxidative stress during the pathogenic process as HP is a plasma protein that binds free hemoglobin and its polymorphism results in proteins with altered hemoglobin-binding capacity and different antioxidant and iron-recycling functions.

Introduction and Objective: Chronic obstructive pulmonary disease (COPD) is often accompanied by lung cancer. Among the genes that may play a role in the occurrence of COPD and lung cancer are those encoding the proteolytic enzymes, such as matrix metalloproteinases (MMPs) and their tissue inhibitors. The objective of this study was to find MMPs-associated markers useful in the identification of COPD subjects with increased susceptibility to developing lung cancer., Materials and Methods: We compared the frequency of single nucleotide polymorphisms in genes coding for matrix proteinases (MMP1, MMP2, MMP3, MMP9, MMP12) as well as tissue inhibitor of metalloproteinases (TIMP1) in two groups of subjects: COPD patients (54 subjects) and COPD patients diagnosed for lung cancer occurrence (53 subjects).The levels of the respective proteins in blood serum were also analyzed., Results: The frequencies of 2 genotypes, MMP3 rs3025058 and MMP3 rs678815, were significantly different between the studied groups. In both cases, more heterozygotes and less homozygotes (both types) were observed in the COPD group than in the COPD + cancer group. A significantly higher TIMP1 level in blood serum was observed in the COPD + cancer group than in the COPD group. There were no statistically significant differences in MMPs blood levels between the studied groups. In addition, no genotype-associated differences in TIMP1 or MMPs blood levels were observed., Conclusions: Homozygocity for MMP3 rs3025058 and rs678815 polymorphisms is a potential marker of enhanced susceptibility to lung cancer development among COPD subjects.

Introduction: Recent studies have shown an increased risk of lung cancer in patients with bronchial obstructive changes, including patients with COPD. It seems that there are common factors of pathogenesis of both diseases associated with oxidative stress. In the present paper the genes linked to the repair of oxidative damage of DNA, associated with cancer, of iron metabolism and coding proteolytic enzymes were assessed., Material and Methods: The study was conducted in two groups of patients: 53 patients with non-small cell lung cancer and chronic obstructive pulmonary disease, and 54 patients only with chronic obstructive pulmonary disease. The polymorphisms of the single nucleotide were determined in the case of the majority of genes using the PCR-RFLP method. The statistical analysis of quantitative variables was executed using the Mann-Withney U-test and the test of medians; the analysis of genetic variables was executed using the chi² test., Results: Regarding the polymorphisms of genes involved in iron metabolism, statistically significant differences between the two groups have been demonstrated only in the case of haptoglobin gene HP1/2. A higher incidence of form 1/1 was found in patients with COPD and a higher incidence of form 1/2 in patients with lung cancer and COPD. Analysis of gene polymorphisms of proteolytic enzymes and inhibitors of the enzyme gene showed statistically significant differences between the two groups only for the MMP3 gene 6A/5A. In the case of the MMP12 gene polymorphism (A-82G) a tendency toward differences in the occurrence of specific alleles was identified., Conclusions: These results indicate that patients with coincidence of COPD and lung cancer have disorders of the genes involved in iron metabolism, and they have different genetic polymorphisms of proteolytic enzymes comparing to COPD patients.

Fesselin is a basic protein isolated from smooth muscle which binds G-actin and accelerates its polymerization as well as cross-links assembled filaments [J. Muscle Res. Cell Motil. 20 (1999) 539; Biochemistry 40 (2001) 14252]. In this report experimental evidence is provided for the first time proving that fesselin can interact with calmodulin in a Ca(2+)-dependent manner in vitro. Using ion exchange, followed by calmodulin-affinity chromatography, enabled us to simplify and shorten the fesselin preparation procedure and increase its yield by about three times in comparison to the procedure described by Leinweber et al. [J. Muscle Res. Cell Motil. 20 (1999) 539]. Fesselin interaction with dansyl-labelled calmodulin causes a 2-fold increase in maximum fluorescence intensity of the fluorophore and a 21nm blue shift of the spectrum. The transition of complex formation between fesselin and calmodulin occurs at submicromolar concentration of calcium ions. The dissociation constant of fesselin Ca(2+)/calmodulin complexes amounted to 10(-8)M. The results suggest the existence of a direct link between Ca(2+)/calmodulin and fesselin at the level of actin cytoskeleton dynamics in smooth muscle.

Four patients with alpha-1 antitrypsin (alpha-1 AT) deficiency are presented: one woman with severe (phenotype PiZ) and 3 men with moderate (phenotype PiMZ) deficiency of alpha-1 AT. The variability of clinical presentation of hereditary emphysema is described. In all patients tobacco smoking history, spirometric and 6-minutes walking tests as well as HRCT of the lung were performed and compared. The influence of smoking on the functional status is underlined.

Spirometric screening for airflow obstruction in smokers is easy in large cities. However, 38% of the population of Poland live in villages. The aim of the study was to assess feasibility of such screening in people attending Sunday mass using parochial church facilities in small remote communities. Study was performed in a small town and a village near Warsaw. Attendance was higher in town (9% of believers attending holy mass as compared 5% in the village). However, airflow obstruction was found in 38% of farmers as compared to 21% of the town dwellers. In conclusion spirometric screening in small communities performed in the parochial facility on Sunday morning is feasible, easy and fruitful.

Kinetics of the smooth muscle calponin-F-actin interaction was studied by stopped-flow measurements of light scattering and fluorescence intensity of pyrene-labelled F-actin. The intensity and character of the changes in light scattering, and thus the mode of calponin binding to actin filaments leading to changes in their shape and bundling, depend on the molar ratio of the two proteins. Parallel measurements of pyrene-fluorescence quenching upon calponin binding revealed that intrinsic conformational changes in actin filaments are delayed relative to the binding process and are not markedly influenced by the mode of calponin binding. Bundling of actin filaments by calponin was not correlated with fluorescence changes and thus with alterations in the structure of actin filaments.

The aim of the study was to evaluate factors that could predict smoking cessation after a minimal antismoking counseling during spirometric screening for COPD. Every subject filled-in a simple questionnaire on clinical signs of COPD and tobacco habit, had a spirometry performed according to ATS standards and received a short antitobacco counseling together with a booklet on how to quit smoking. Out of 800 smokers over 40 years of age, smoking history of more than 10 packyears, screened for COPD in 1999, four hundred were invited a year later for a follow-up spirometry and evaluation of anti-smoking intervention. Of 383 patients, who responded to the invitation (208 M and 175 F, mean age 56.6 +/- 10.7 yrs), 52 (13.6%) quit smoking for one year and another 48 (12.5%) quit smoking temporarily and than resumed smoking. Smokers who permanently succeeded in quitting smoking were older (60.5 vs 55.9 years p < 0.01), started smoking later (age at starting smoking 22 vs 19.5 years p < 0.001), had a shorter tobacco exposition (28.8 vs 34.3 packyears p < 0.05), had lower lung function (FEV1%pred 80.5 vs 89.2% p < 0.05) and were less nicotine dependent (FTQ score 1 vs 4.8 p < 0.00001).

Calponin is a smooth-muscle thin-filament protein implicated in the regulation of contraction. Its binding to actin is a prerequisite for inhibition of actin-activated myosin MgATPase. Investigating the molecular mechanism of this inhibition, it was found that titration of acto-myosin subfragment 1 with calponin in the presence of either ADP or ATP does not displace weakly or strongly bound myosin subfragment 1 (S1) from actin. S1.ADP, however, is able to release about two-thirds of the calponin from saturated (equimolar) complexes of actin-calponin. The remaining calponin is sufficient for almost full inhibition of acto-S1 MgATPase activity. Bunding of actin filaments by calponin takes place at a higher ratio calponin/actin (above 1:3) and, therefore, is not responsible for inhibition of the ATPase. Bundle formation is inhibited by S1.ADP. These results suggest the existence of two calponin-binding sites on actin; one, that is insensitive to S1, which is responsible for inhibition of the ATPase, the other, from which calponin is readily displaced by S1.

Limited proteolysis of actin with trypsin removes its two or three C-terminal amino acid residues [Proc. Natl. Acad. Sci. USA 81 (1984) 3680-3684]. Carboxypeptidase B-treatment of G- and F-actin previously digested with trypsin revealed that in the first case preferential release of three and in the second two C-terminal amino acid residues takes place. Tryptic removal of three but not two C-terminal amino acid residues of actin causes weakening of its interaction with caldesmon and lowering of the caldesmon-induced inhibitory effect on actomyosin ATPase activity. Therefore, it is concluded that the third amino acid residue from the C terminus of actin, Lys-373, is important for the interaction with caldesmon.

Proteolytic elimination of three C-terminal amino acid residues from actin weakens its interaction with caldesmon and troponin I and, in consequence, lowers the inhibitory effects of both proteins on actomyosin ATPase activity. These results prove the importance of C-terminal extremity of actin to the overall interaction of this protein with caldesmon and troponin I.

In the studies carried out lipids content in blood serum and aorta wall as well as morphological changes in coronary vessels of CS2 exposed rats have been evaluated. The 10-month-exposure to CS2 at a concentration of 0,8--0,9 mg/l has been found to result in: (1) increased concentration of total and free cholesterol, cholesterol esters, triglycerides and phospholipids in blood serum; (2) increase in total cholesterol and significant rise in the level of cholesterol esters in the aorta wall; (3) a relative increase in serum VLDL, LDL and decrease in HDL fraction. Histological estimation has demonstrated in serial sections of hearts of the CS2 exposed animals thickened walls of left coronary artery branches with no lipid deposits. In two animals focal steatosis of aortic bulb wall and aortic valves and lipids droplets in endothelium of ascending aorta and coronary vessels have been found.

Fibrogenic effect of two natural amorphous silica dusts-diatomite from deposits near Leszczawka (Poland) and silica earth (from the USA) was tested on the rats. Pneumoconiosis was produced by intratracheal introduction of 50 mg dust, at a single dose. Fibrogenic effect was assessed after 3, 6 and 9 months after introduction of dust. Analysis of diatomite dust carried out with X-ray diffraction method showed the presence of quartz in a quantity not exceeding 5%, while in silica earth dust from the USA no silica critalline structures were found. Development of fibrogenic changes in lungs of the rats assessed with hydroxyproline (collagen) increase and weight increment of wet lungs was small. The increment of the indices was twice higher as compared with their increment found in the lungs of control animals but lower than in the rats which were given cristalline silica dusts. In histopathological examinations no progressive lung fibrosis was found though some signs of destruction and necrobiosis in some cells were noticed.

The activity of microsomal cytochrome P-450 monooxygenase and ultrastructure of the liver have been studied in rats exposed dynamically to 50, 500, and 20,000 ppm of vinyl chloride (VC) over 10 months. After 1 and 3 months of exposure to 500 and 20,000 ppm of VC, the level of cytochrome P-450 was slightly lower than in the control animals and upon continuation of exposure it was restored to the original level accompanied by slight increase of activity of aniline p-hydroxylase. Liver enlargement, developed in the course of the exposure, was accompanied by ultrastructural alterations beginning in the 3rd month of exposure to all concentrations of VC. Development of hepatic alterations (hypertrophy of smooth and rough endoplasmic reticulum, swelling of mitochondria, accumulation of lipid droplets, focal cytoplasmic degradation) is discussed with regard to the activity of microsomal monooxygenase system in metabolizing VC to toxic metabolites.

The effect of chronic ethanol (EtOH) administration on CS2-induced peripheral neuropathy in rats was studied. Rats were exposed to 0.8 mg/l CS2 for 12-15 months and to 10% EtOH as only drink during the last 4 months of the experiment. Some biochemical correlates of Wallerian degeneration of the peripheral nerve were estimated and ultrastructural examinations of the peripheral nerves were performed. It was shown that EtOH augmented the alterations in lipid content provoked by CS2 in the peripheral nerves, i.e. an increase in cholesterol esters and in the ratio of cholesterol esters to free cholesterol (E/F ratio) and a decrease in phospholipid content. The magnitude of ultrastructural changes induced by CS2 in the nerves was increased by EtOH.

In view of divergent opinions concerning MAC value for vinyl acetate, a study on acute and chronic inhalatory toxic effect of this compound on animals was carried out. The scope of the study included determination of CL50 value after Litchfield and Wilcoxon and 10-month exposure of animals to vinyl acetate at concentrations 10, 100 and 500 mg/m3, 5 days weekly, 5 hours daily. During 10-month experiment the animals were observed and body weight controlled. In addition, periodically some hematological examinations and biochemical of blood serum as well as histopathological examinations of inner organs were carried on. Post-mortally the weight of inner organs was determined. CL50 value determined on rats has amounted to 4100 ppm. In the study on chronic effect, the prevalence and the degree of intensity of the changes of the used by us indicators was the least in the group of animals exposed to vinyl acetate at concentration of 10 mg/m3. These changes were transient not involved reticulopenia and animals' body weight decrease. Histopathological examinations revealed some inflammatory changes in respiratory system both in control and exposed animals. Only planoepithelial metaplasia of bronchi was found exclusively in animals exposed to vinyl acetate at all concentrations used. The changes within liver were found only in animals exposed to vinyl acetate at concentration of 100 and 500 mg/m3. These changes involved fatty degeneration of hepatic parenchyma, proliferation and extension of smooth endoplasmatic reticulum and the changes within the biliary canaliculi. Taking the above results into account it seems that the lowest of the recommended in the world MAC value--10 mg/m3 may be accepted as the upper limit of the maximum admissible concentration for vinyl acetate.

Neurotoxic effects of the combined exposure of rats to carbon disulphide (CS2) and ethanol (EtOH) were studied. Biochemical and ultrastructural evaluation of the central nervous system (CNS) and peripheral nervous system (PNS) was performed. Male Wistar rats were exposed to CS2 vapour (0.8 mg/l air) and to 10% alcohol in the drinking water for 8 months. EtOH elevated the increase in beta-glucuronidase activity caused by CS2 in the hippocampus and in the cerebral cortex. No effect on the high-affinity synaptosomal uptake of L-glutamate and GABA was observed and no marked ultrastructural changes in the tested brain regions were found. In the peripheral nerves CS2 alone evoked axonal degeneration whereas CS2 combined with EtOH caused disturbances in myelin. Ultrastructural changes preceded biochemical alterations in the PNS and the biochemical indicators of peripheral neuropathy such as beta-glucuronidase activity and cholesterol ester content were not significantly affected. It is suggested that CS2 and EtOH combined affect both PNS and CNS to a higher extent than each of these substances alone.

Fibrogenous effects of wollastonite, chrysotile and crocidolite have been investigated in experiments on animals. (Wollastonite is a calcium silicate of fibrous structure, occasionally applied as asbestos substitute). The experimental animals were intratracheally administered single doses of 50 mg of the test material suspended in 0.6 ml of physiological NaCl solution. The animals were decapitated 3, 6 and 9 months after the experiment. Fibrogenic properties were evaluated basing on the weight of wet lungs, content of lipids and hydroxyproline in lungs, as well as histopathological tests of lungs, mediastinal lymph nodes and spleen. Histopathological preparations were evaluated using an optical, microscope or transmission electron microscope. The findings of biochemical, pathomorphological, and ultrastructural studies demonstrated slight fibrogenic effects of wollastonite, as compared to chrysotile and crocidolite.

Rats were exposed to carbon disulphide (CS2) continuously for 12 h or for 10 months, at concentrations of 2.4 mg/l air and 0.8 mg/l air, respectively. No changes in the brain content of ATP, ADP and AMP were found in rats after chronic exposure, whereas the content of ATP in the brain of rats acutely poisoned with CS2 was significantly higher (21%) accompanied by decrease in the content of ADP (10%) and AMP (45%). The biochemical changes were accompanied by ultrastructural changes of mitochondria, particularly those in the cerebellar perikaryons.

Fibrogenic properties of two dusts of synthetic hydrated amorphous silicas, Ze-O-Sil (French production) and Arsil (Polish production) were studied. Experimental silicosis was induced by intratracheal administration to rats of a single dust dose (50 mg in 0.6 ml NaCl). Fibrogenic properties were tested 3, 6, 9 months after administration of the dust. X-ray diffraction and chemical tests did not reveal any form of crystalline. Si02 in the composition of the investigated dusts. The dusts tested as compared with quartz, were characterized by a great solubility up to 211 mg/l, which made the dust excretion from the lungs easy; after 6 month-experiment approximately 1.2 mg of Arsil dust and about 28 mg of quartz dust residue was found. Fibrogenic properties of Arsil dust, represented by wet lungs weight increase and hydroxyproline content in lungs, were more pronounced than those of Ze-O-Sil. Hydroxyproline content 3 months after administration of Arsil, Ze-O-Sil, TiO2 and weak quartz amounted to 7.3 mg, 5.1 mg, 3.8 mg and 6.0 mg, respectively. Histological and ultrastructural investigations demonstrated that disseminated, multifocal granulomas were the basic reaction to both dusts; no clear histological signs of cytolytic action on the cells of dust granulomas were found. In the lungs no silicotic nodules or degeneration of changes were revealed. Neither biochemical tests nor histological examinations revealed a progressive development of fibrous connective tissue. In result of the studies the authors suggest 2 mg/m3 as a MAC value for Arsil dust instead of 10 mg/m3--the value which has been hitherto used.