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Biomedical subjects

R Andrzejak

Publications and source records attributed to R Andrzejak.

At least 19 recordsLinked to original sources
PubMed2001

Lead-cadmium interaction effect on the responsiveness of rat mesenteric vessels to norepinephrine and angiotensin II.

The comparison of the reactivity to norepinephrine (NE) and angiotensin II (A II) of isolated mesenteric blood vessels obtained from rats simultaneously poisoned with lead and cadmium to those responses of rats treated singly with lead or cadmium was performed. Male Buffalo rats aged 6-8 weeks were administered intragastrically with lead (35 mg Pb/kg body wt.) and/or cadmium (5 mg Cd/body wt.), once a week for a period of 7 weeks. Control rats were given equimolar amounts of sodium acetate and/or sodium chloride. Changes in mesenteric vascular resistance due to NE and A II injections were measured ex vivo as an increase in perfusion pressure in vessels prepared by McGregor's method. The dose-response curve for NE (0.01-5.0 microg) determined for vessels of rats poisoned simultaneously with lead and cadmium was shifted to the left in comparison to controls (not poisoned rats), similarly to these determined for rats poisoned with lead or cadmium. ED(50) NE pointed out in the control group (0.83+/-0.5 microg) was significantly greater than in metal treated groups (0.44+/-0.09; 0.45+/-0.26 and 0.5+/-0.11 microg in lead, cadmium, lead and cadmium-treated rats, respectively). This study indicated a tachyphylaxis in responses of isolated mesenteric vessels to A II injected in increasing doses, and the weaker, in comparison to controls, response of vessels of rats poisoned with lead and/or cadmium to A II at a dose of 0.4 microg. The decreasing response to A II could result from changes in calcium ions transport through L-type channels in vascular smooth muscle cells, because verapamil (2.0 microM) inhibited the A II-induced vasoconstriction more weakly in rats poisoned with metals than in controls. Inhibitor of prostaglandins synthesis, ketoprofen (200 microg/ml per min.) attenuated the pressor effect of NE in blood vessels obtained from all rats, but this effect was less potent in arteries of cadmium poisoned rats. Ketoprofen also inhibited the vasoconstrictory action of A II in all groups, but this effect was lower in vessels of rats poisoned simultaneously with lead and cadmium. We suggest that the release of vasoactive prostaglandins as a consequence of endothelial angiotensin receptor stimulation changes more under the influence of metals administered to rats simultaneously than under the influence or lead or cadmium administered singly. Treatment with a nitric oxide synthase inhibitor (L-NOARG; 22 microg/ml per min.) potentiated a NE-induced pressor response in all groups. However, the increase in perfusion pressure was greater in rats poisoned with cadmium in comparison to controls. L-NOARG potentiated the A II induced vasoconstriction only in cadmium poisoned rats, also indicating a greater influence of nitric oxide in cadmium treated rat vasculature. Two-way ANOVA showed the existence of lead-cadmium interactions effects on the reactivity of rat isolated mesenteric vessels to NE, A II and papaverine.

Analysis of Variance↗
PubMed2001

Serum lipid peroxide levels and erythrocyte glutathione peroxidase and superoxide dismutase activity in premenopausal and postmenopausal women.

Free radical reactions are involved in processes connected with aging. Estradiol acts as antioxidant and free radical scavenger, but the mechanism of this action remains unknown. Estradiol has a hydroxyphenolic structure and may donate hydrogen atoms to lipid peroxyradicals to terminate chain reactions. There are a few reports concerning the influence of estradiol on natural antioxidant enzyme activity, such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT). The aim of this study was to estimate the relationship between the levels of estradiol and lipid peroxide (LPO), a marker of membrane lipid peroxidation, and the correlation between estradiol and erythrocyte SOD and GSH-Px activity. The study included 13 premenopausal and 13 postmenopausal healthy women. Serum levels of estradiol, follicle-stimulating hormone (FSH) and LPO, and erythrocyte SOD and GSH-Px activity were estimated in all subjects. Premenopausal women revealed significantly higher estradiol levels and lower LPO concentrations, as well as significantly higher GSH-Px activity than the postmenopausal group. SOD activity did not differ between the two groups. There was a negative correlation between serum estradiol and LPO levels as well as a positive correlation between estradiol and GSH-Px activity. These results support the hypothesis that estradiol exerts its antioxidant action not only through its chemical structure but probably also through its influence on natural cellular antioxidant enzyme activity.

Case-Control Studies↗
PubMed2001

[Is there any risk interaction between electromagnetic field generated by mobile phones and artificial pacemakers].

Electromagnetic noise is rapidly increasing in the environment. Electromagnetic fields (EMF) originating from a variety of different sources have been shown to interfere with the function of implanted cardiac pacemaker. The authors present the effect of EMF generated by wireless telephones on different types of artificial pacemakers. In addition, instructions on safe use of mobile phones addressed to people with implanted artificial pacemaker are provided.

Arrhythmias, Cardiac↗
PubMed2001

[Vanadium: threat and hope].

Vanadium is an element classified in the group of heavy metals, very common in the natural environment and widely used in industry. It is mainly used in the production of nonferrous alloys, most resistant carbon steel, as well as in chemical, glass, paint and varnish, ceramic, and photographic industries. In the atmosphere, two second of vanadium originates from anthropogenic sources, sea-born aerosols and volcanic eruptions. Municipal waste is the major source of vanadium in surface water. It is one of the components of live organisms and participates in many biochemical processes essential for their proper functioning, but in higher concentrations it may induce acute or chronic intoxication that damage biological structures and disorder biochemical systems. The mechanism of vanadium toxic effect has not as yet been elucidated, however, it is already known that this mechanism is rooted among others in vanadium properties able to hinder a number of enzymatic systems. For vanadium the most "critical" systems are respiratory, urinary and hemopoietic. Vanadium salts may also be genotoxic and harmful at different phases of reproduction and development. Numerous studies of a possible use of vanadium in treatment of certain diseases, e.g., diabetes, have been carried out. Some findings on a potential antineoplastic or contraceptive effect of vanadium compounds have recently been reported. To sum up, there are numerous hazards associated with the wide industrial use of vanadium, nevertheless, the number of findings highlighting its nutritive and therapeutic properties is growing.

Antineoplastic Agents↗
PubMed2001

[Urinary trehalase activity as an indicator of renal dysfunction in lead smelters].

Epidemiological and experimental studies have demonstrated that lead and cadmium are responsible for renal dysfunction. Urinary trehalase is known as a good marker of proximal tubular renal brush border destruction in the population environmentally exposed to cadmium. The aim of this study was to determine the impact of occupational exposure to lead on the renal function and urinary trehalase activity. The study was carried out in 68 workers, aged 46 +/- 6 years, employed in a copper foundry. Blood lead, cadmium, copper and manganese concentrations were measured by atomic absorption spectrophotometry. Urinary trehalase activity was determined by the method of Nakano and Itoh. Trehalase activity was increased in copper smelters as compared to controls. There also was a positive linear correlation between blood lead level and urinary trehalase activity (r = 0.44; p < 0.05). Negative correlations between blood lead and copper concentrations (r = -0.30; p < 0.05) and between serum copper and trehalase level (r = 0.68; p < 0.001) were found. The results show that urinary trehalase activity could be a good indicator of the renal brush border dysfunction in copper smelters. This marker could be useful in the early diagnosis of nephrotoxic effect of lead.

Cadmium↗
PubMed2000

Nonlinear EEG analysis and its potential role in epileptology.

Deterministic chaos offers a striking explanation for apparently irregular behavior of the brain that is evidenced in the EEG. Recent developments in the physical-mathematical framework of the theory of nonlinear dynamics (colloquially often termed chaos theory) provide new concepts and powerful algorithms to analyze such time series. Because of its high versatility, nonlinear time series analysis has already gone beyond the physical sciences and, at present, is being successfully applied in a variety of disciplines, including cardiology, neurology, psychiatry, and epileptology. However, it is well known that different influencing factors limit the use of nonlinear measures to characterize EEG dynamics in a strict sense. Nevertheless, when interpreted with care, relative estimates of, e.g., the correlation dimension or the Lyapunov exponents, can reliably characterize different states of normal and pathologic brain function. In epileptology, extraction of nonlinear measures from the intracranially recorded EEG promises to be important for clinical practice. In addition to an immense reduction of information content of long-lasting EEG recordings, previous studies have shown that these measures enable (a) localization of the primary epileptogenic area in different cerebral regions during the interictal state, (b) investigations of antiepileptic drug effects, (c) analyses of spatio-temporal interactions between the epileptogenic zone and other brain areas, and (d) detection of features predictive of imminent seizure activity. Nonlinear time series analysis provides new and supplementary information about the epileptogenic process and thus contributes to an improvement in presurgical evaluation.

Brain Mapping↗
PubMed2000

[Serum selectin E level in lead-exposed workers].

Lead is recognised as a potential atherogenic factor. One of the earliest events in the development of atherosclerosis is monicyte attachment to the endothelial surface. This is followed by recruitment of monocytes into the subendothelial space and ingestion of modified LDL by these cells. In turn, modified LDL stimulates endothelial cells to induce expression of proinflammatory adhesion molecules, such as selectins, which further promote monocyte migration. It was observed that atherosclerotic vascular damage is associated with increased level of circulating selectin E. The aim of this study was to determine the impact of the occupational exposure to lead on the serum selectin E level. The study involved 80 patients, including 37 workers of a copper foundry and 43 people not exposed to lead. The subjects were matched in pairs according to sex, age and cholesterol concentration in blood. There were 25 hipercholesterolemic pairs and 9 pairs with normal serum total cholesterol. People exposed to lead had higher (about 7 ng/ml) serum selectin E concentration than those not exposed. There was positive linear correlation between selectin E and triglycerides in the whole group (p < 0.01), and the strongest correlation was observed in the group of subjects not exposed to lead (aged 40-60, r = 0.74). In the context of the described hypertriglyceridemic action induced by lead, these results suggest that lead could potentially act as an atherogenic factor in the early, inflammatory stage of atherosclerosis.

Adult↗
PubMed2000

[Preliminary assessment of occupational exposure to Glutaraldehyde in selected endoscopic workplaces].

The effect of occupational exposure to glutaric aldehyde in 17 endoscopic laboratories of the Wrocław region was assessed. The level of glutaraldehyde concentration was measured, and the survey was carried out in a group of 34 laboratory employees. In 11 laboratories MAC and STEL values were exceeded. Undesirable effects following the contact with glutaric aldehyde were noted in 28 subjects (82%). The skin, mucous membrane and respiratory system irritations predominated among the symptoms observed. The data show that glutaric aldehyde may induce irritation or exert an allergic effects in medical personnel.

Disinfectants↗
PubMed2000

[Effect of arsenic and its compounds on the circulatory system].

Arsenic is a metal which occurs widely in both occupational and physical environments. Therefore, its easy accessibility and high toxicity raise the question on whether arsenic, particularly in relatively small doses, can cause damage of relevant molecular, biochemical and clinical significance to the cardiovascular system. The present review is focused on the confirmed and potential mechanisms of arsenic effect on the function and structure of vascular endothelium (nitric oxide, peroxynitrite), its role in stimulating the oxidative species formation (hydroxyperoxide, superoxide and lipid peroxide formation), as well as in decreasing the antioxidative response (enzymes: superoxide dysmutase, catalase, glutation peroxidase), its cytotoxic effects, including immunotoxic properties, arsenic action in the signal transduction pathways network (kinases and DNA transcription factors), impact on cell proliferation, differentiation and apoptosis, not to mention its interference with DNA synthesis and repair processes. Apart from mechanisms of arsenic action, the article provides the up-to-date information on various cardiovascular diseases of the established or presumed arsenic origin.

Animals↗
PubMed1999

[Cytostatic drugs: occupational hazard to health care workers].

Cytostatic anticancer drugs are known as carcinogenic, mutagenic, and teratogenic risk factors for health care workers who are occupationally exposed during preparation and management of such drugs. Risk assessment for occupational exposure to antiblastic chemotherapeutic drugs is carried out by means of environmental and biological monitoring. During last twenty years, several researchers have developed and validated methods for monitoring occupational exposure to such agents. The author reviews the literature on possible effects of occupationally exposed hospital workers and occupational exposure.

Antineoplastic Agents↗
PubMed1999

[Chromium carcinogenicity].

Chromium belongs to the group of trace elements hich are essential in numerous functions of the human body. Chromium deficiency may be responsible for various dysfunctions, whereas exposure to chromium at higher concentrations is toxic and may lead to the occurrence of neoplastic diseases. Epidemiological studies of chromium exposure proved its carcinogenity, and thus the IARC recognised Cr(VI) and its compounds as one of ascertained carcinogens. Some findings of these studies were reviewed in the first part of this work. The second part presents some molecular aspects of chromium carcinogenity which are still the subject of medical research. The direct and indirect effects of chromium and its compounds on DNA are analysed as are the relationships between the level of chromium oxidation and carcinogenity, and between the presence of reductants and the kind of DNA damage. Methods for the assessment of chromium mutagenity and genotoxicity are also discussed, and special attention is paid to tests of mutation in bacteria and yeast as well as to sister chromatid exchange (SCE) test.

Antimutagenic Agents↗
PubMed1999

Is it possible to anticipate seizure onset by non-linear analysis of intracerebral EEG in human partial epilepsies?

Detection of electrophysiological features preceding and indicative of imminent seizures in patients with epilepsy would be a major breakthrough with immense scientific and clinical implications. The definition of a "pre-ictal state" several minutes prior to seizure onset would open a new time window for studying mechanisms of seizure generation as well as for possible therapeutic interventions. In this review we present recent findings from nonlinear time series analysis of intracranially recorded EEG that may allow to forecast seizure onset in patients with partial epilepsy.

Animals↗
PubMed1997

[Problems of environmental exposure to toxic effects of glutaraldehyde in medicine].

Glutaraldehyde is an antibacterial and antiviral agent commonly used for cleaning and disinfection of endoscopic equipment. The accepted glutaraldehyde air-concentration is 0.2 ppm. The irritant action, allergic potential and possible neurotoxicity of glutaral have been reported. Red eyes, cough, headache and running nose are most frequent symptoms of glutaral activity. The incidence of bronchial asthma and contact dermatitis has also been reported. In order to avoid occupational hazards of glutaraldehyde closed washing-disinfection systems, proper ventilation (20 cycles per hour), vapour recovery safety nozzle and neutralizing agent should be used.

Asthma↗
PubMed1997

[Atypical case of bronchial carcinoid].

This article illustrates problems in diagnosis and treatment of an atypical form of bronchial carcinoid. We described the case of a 49-year old man, exposed to granite dust and noise for 25 years who had suffered from frequent bronchitis inflammations and pneumonias for 5 years prior to the diagnosis. He was admitted to our clinic because of supposed occupational nature of hearing deficiency. Although a pneumoconiosis was excluded before the admission, we found clinical and X-ray features of the right lung emphysema with medium restrictive ventilation disturbances. Bronchoscopy was performed because of "bright" right lung and ventilation disturbances and it showed presence of the carcinoid. Unusual in this case were tiny anamnestical findings (mild dyspnea attacks after physical effort or nervousness) plus increasing frequency of reported from the childhood bronchitis and pneumonias and uncharacteristic "bright" right lung in X-ray. Therapeutical difficulties resulted from atypical histological form of the tumor, its diameter, polypous-infiltrative character, and inconvenient localization. In spite of late diagnosis of carcinoid and significant acceleration of respiratory decompensation symptoms after the diagnosis the attempt of surgical therapy was appropriate but unsuccessful. After the operation the patient was suffering long lasting lowering of arterial pressure (what was corrected with catecholamine infusions) probably as a result of serotonin secretion. However it was not established because of technical reasons.

Bronchial Neoplasms↗
PubMed1996

[Blood lipid parameters in smelters chronically exposed to heavy metals].

A group of 120 male workers, employed in copperworks (mean age = 41.5 years; mean exposure duration = 17,9 years) at workposts with the highest level of exposure to lead, were covered by the study. Blood levels of the following heavy metals were measured in all workers: Pb, Cd, Mn, Cu, Zn, Ca, Mg as well as concentrations of FEP and GSH, SOD activity in erythrocytes, parameters of lipid metabolism: total cholesterol, HDL2- HDL3-cholesterol, triglycerides, lipid peroxides (LPO), and lecithin-cholesterol acyltransferase (LCAT) activity. Mean blood lead level accounted for 251,86 micrograms/l, and mean level of FEP was slightly above normal. That may indicate moderate lead deposits in smelters. Concentrations of other metals remained within normal limits. No significant disturbances in lipid metabolism were observed. Along with expected positive correlation between lead blood level and FEP, a significant negative correlation between lead and cholesterol levels as well as between FEP and serum cholesterol was found. Moreover, a significant negative correlation between FEP and serum LPO, as well as a significant positive correlation between concentration and HDL2-cholesterol level and between FEP concentration and SOD activity in erythrocytes were noted. We believe that unexpected outcome of our investigations could result from the adaptation of healthy smelters to the environmental conditions. It is assumed that further exposure could weak antioxidant mechanisms and lead, in consequence, to the manifestation of symptoms induced by harmful effect of free radicals.

Adult↗