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Biomedical subjects

M Krzyzanowski

Publications and source records attributed to M Krzyzanowski.

At least 19 recordsLinked to original sources
PubMed2005

DNA repair polymorphisms and cancer risk in non-smokers in a cohort study.

Environmental carcinogens contained in air pollution, such as polycyclic aromatic hydrocarbons, aromatic amines or N-nitroso compounds, predominantly form DNA adducts but can also generate interstrand cross-links and reactive oxygen species. If unrepaired, such lesions increase the risk of somatic mutations and cancer. Our study investigated the relationships between 22 polymorphisms (and their haplotypes) in 16 DNA repair genes belonging to different repair pathways in 1094 controls and 567 cancer cases (bladder cancer, 131; lung cancer, 134; oral-pharyngeal cancer, 41; laryngeal cancer, 47; leukaemia, 179; death from emphysema and chronic obstructive pulmonary disease, 84). The design was a case-control study nested within a prospective investigation. Among the many comparisons, few polymorphisms were associated with the diseases at the univariate analysis: XRCC1-399 Gln/Gln variant homozygotes [odds ratios (OR) = 2.20, 95% confidence intervals (CI) = 1.16-4.17] and XRCC3-241 Met/Met homozygotes (OR = 0.51, 95% CI = 0.27-0.96) and leukaemia. The recessive model in the stepwise multivariate analysis revealed a possible protective effect of XRCC1-399Gln/Gln in lung cancer (OR = 0.22, 95% CI = 0.05-0.98), and confirmed an opposite effect (OR = 2.47, 95% CI = 1.02-6.02) in the leukaemia group. Our results also suggest that the XPD/ERCC1-GAT haplotype may modulate leukaemia (OR = 1.28, 95% CI = 1.02-1.61), bladder cancer (OR = 1.38, 95% CI = 1.06-1.79) and possibly other cancer risks. Further investigations of the combined effects of polymorphisms within these DNA repair genes, smoking and other risk factors may help to clarify the influence of genetic variation in the carcinogenic process.

Adult↗
PubMed2003

The right to healthy indoor air: status by 2002.

One of the reasons for the inadequate quality of indoor air arises from the poor articulation, appreciation and understanding of basic principles underlying the policies and actions related to indoor air quality. A WHO Working Group derived nine statements on rights to healthy indoor air. The discussions and statements are available as a WHO report. It informs the individuals and groups responsible for healthy indoor air about their rights and obligations, and empowers the general public by making people familiar with those rights. One year after their publication the statements have been adopted as the base for future regulation and guidance. The Board of Directors of the International Society of Indoor Air Quality (ISIAQ) and the participants of two international conferences endorse the use of the statements. No opposition to the statements have been registered. The statements have entered curricula of training courses and have been used in lawsuits.

Air Pollution, Indoor↗
PubMed2003

Health impact assessment of air pollution: providing further evidence for public health action.

Many epidemiological studies have demonstrated the importance of air pollution as a risk factor and characterised dose-response relationships between health endpoints and pollutants. The association between particulate matter (PM) and health is generally regarded as causal, and a nonthreshold linear relationship with, for example, mortality and hospital admission has been observed in several settings. The ubiquitous PM air pollution is likely to have a large overall impact on human health, even if risks are relatively small. There have recently been a large number of papers reporting quantitative estimations of the health impact of PM on health, as measured by the proportion of excess events that are attributable to PM exposures in the general population, mainly in industrialised countries. For example, in the eight largest Italian cities it has been estimated that concentrations beyond 30 microg x m(-3) are responsible for about 3,500 extra deaths per year. A similar study has been carried out for France, Austria and Switzerland. These evaluations fill a knowledge gap between the laboratory and clinical studies on the pathophysiological mechanisms, the epidemiological research on the nature and strength of the association at the population level, and the risk management needs for developing appropriate preventive policies. Some limitations in the methodology deserve further research, however health impact assessment type studies are informative and effective tools of communication with the general public and policy makers.

Aged↗
PubMed2003

Selenium concentrations in human renal cortex, liver, and hair in northern Poland.

The aim of this study was to (1) determine the selenium concentration in the renal cortex, liver, and hair in 64 residents from northern Poland (Gdańsk region) aged 17-81 yr, who died suddenly, and (2) assess whether a correlation between the selenium concentration in hair and in the renal cortex and liver occurs. Selenium was determined by atomic absorption spectrometry using the hydride generation method. The mean selenium concentration in the renal cortex, liver, and hair in the investigated persons was 0.791+/-0.191 microg/g (wet weight), 0.289+/-0.084 microg/g (wet weight), and 0.443+/-0.128 microg/g, respectively. No age-dependent differences in selenium level in the investigated tissues was found. Also, no correlation between the selenium concentrations in hair and in renal cortex and liver was assessed.

Adolescent↗
PubMed2002

Regional distribution of glutamate in the central nervous system of rat terminated by carbon dioxide euthanasia.

Carbon dioxide euthanasia is an established method for the termination of small laboratory animals. It has also been employed by the authors in neurobiological research on the post-mortem glutamate concentration in the structures of rat brains. The following investigations were aimed at optimizing the termination procedure based on the CO2 saturation rate of the inhaled air. Two rates of CO2 flow were applied, and the higher one significantly augmented the glutamate level in the hippocampus and cerebellum. The relationship between this finding and signs of central fear reaction is discussed. The authors conclude that lower rather than higher CO2 flow in euthanasia procedures is gentler and is therefore preferable for use with laboratory animals.

Animals↗
PubMed2001

Haemorrhages in head tissues during the asphyxiation process.

Two rates of carbon dioxide flow into the termination chamber were applied for the euthanasia of rats. The classical phases of asphyxia were observed in both groups of animals although their course was prolonged in rats exposed to the lower gas flow. The haemorrhages were assessed histologically in the following structures: the pericranium, compact bone and diploë of the skull, sagittal suture, nape muscle and its attachment, and the dura. The haemorrhages appeared regularly in the sagittal suture in all cases from both experimental groups. The possible significance of this phenomenon for the forensic practice was pointed out.

Animals↗
PubMed2001

The post-mortem concentration of glutamate in the structures of rat brain as an exponent of short aversive sensory stimulation preceding death.

The problem of post-mortem assessment of short central fear reaction preceding death has been obscure till now. The preliminary results obtained by authors have encouraged them to further research on this topic. Time of aversive sensory stimulation in the presented study was considerably decreased in comparison to the preliminary investigations. The concentration of glutamate was assayed in the selected structures of limbic system and in the cerebellum. The rats were subjected to different simultaneous modalities of sensory stimulation. The involvement of the hippocampi and the cerebellum was revealed as measured by glutamate concentration increase in the whole structures homogenates. The dominant role of mechanical stimulus has been suggested based on the measured increase of glutamate concentration in the whole cerebellum homogenate. By using the presented experimental paradigm a possible application of the biochemical assessment of human brain tissue might be developed in the future for implementing in the field of forensic pathology. The biochemical evaluation of "frozen frames" of neurotransmission can possibly help reconstruct the events which had happened just before sudden and violent death.

Acoustic Stimulation↗
PubMed2001

The usefulness of CBF brain SPECT in forensic medicine. A description of four cases.

BACKGROUND: The aim of this study was to show the applications of cerebral blood flow SPECT scanning in forensic medicine using four cases: two suspects and two victims of crime. MATERIAL AND METHODS: Cerebral blood flow studies were performed with the use of (99m)Tc-ECD and a triple head gammacamera. Qualitative and quantitative analysis was performed, utilising an asymmetry index for unilateral perfusion deficits and a comparison to cerebellar perfusion for assessing the regional cerebral perfusion. For assessing the normal values, a control group of 30 patients was studied. RESULTS: In these cases CBF SPECT scanning proved its usefulness in medico-legal argument and played an important role in formulating the final forensic expert's opinion. CONCLUSIONS: Radionuclide cerebral blood flow studies may play a role in forensic medicine, where this method it is mostly under-utilised at present.

Journal Article↗
PubMed2000

Total mercury in human renal cortex, liver, cerebellum and hair.

The aim of this study was: (a) to estimate the concentration of total mercury in the renal cortex, liver, cerebellum and hair of 46 persons who died suddenly in the Gdańsk region, northern Poland, between the ages of 17 and 90; and (b) to assess whether a correlation occurs between mercury content in the investigated biological media. The mean concentrations of mercury in the human hair, renal cortex, liver and cerebellum were: 378 +/- 315.4 ng/g; 68.6 +/- 92.3 ng/g; 29.9 +/- 22 ng/g and 5.3 +/- 6.9 ng/g respectively. Positive correlations were found between mercury levels in: cerebellum and liver (r = 0.873), cerebellum and hair (r = 0.853), cerebellum and renal cortex (r = 0.578), hair and liver (r = 0.771), hair and renal cortex (r = 0.478) liver and renal cortex (r = 0.66). The geometric mean levels of mercury in the renal cortex, liver, cerebellum and hair in the residents of the Gdańsk region are 15-19 times lower than in the population of Tokyo and its environs [Suzuki T, Hongo T, Yoshinaga J et al. The hair-organ relationship in mercury concentration in contemporary Japanese. Arch Environ Health 1993;44:361-365].

Adolescent↗
PubMed1999

The concentration of glutamate in cerebral tissue as a factor for the assessment of the emotional state before death. A preliminary report.

In this paper the concentration of glutamate in the hemispheres of the brain, the cerebellum and the brain stems of rats exposed to sensory stimulation before death and of control rats are presented. Statistically significant differences in the concentration of this neurotransmitter were found in the hemispheres of the brain in the cases of stress lasting 10 min and 1 min and in the cerebellum after a stress of 10 min. This suggests that it may be possible to diagnose the post-mortem state of emotional tension related to sensoric aversive input which takes place directly before death.

Acoustic Stimulation↗
PubMed1999

Measurements of the Obersteiner-Redlich zone of the vagus nerve and their possible clinical applications.

The aim of our study was to describe anatomical variability of the root entry zone (REZ), also called the Obersteiner-Redlich zone, that represents the "junction zone" of glia and Schwann sheath of the cranial nerves. This zone has some clinical implications. The pulsatile compression of REZ by a vessel may produce clinical symptoms, such us trigeminal neuralgia, hemifacial spasm, glossopharyngeal neuralgia torticollis spasmodicus or even symptoms of essential hypertension when a vascular cross compression of REZ of a left vagus nerve is present. The vessel--cranial nerve contact in the skull base cysterns may be visualized in radiologic examinations, most accurately in magnetic resonance imaging. Because, we cannot distinguish the REZ from the rest of the vagus nerve in radiologic examinations we decided to measure the length of its REZ. The microanatomical study of the length of REZ zone of the vagus nerve was performed on 21 nerves taken from 17 human brain stems (12 men, 5 women, 14 left, 7 right), fixed with 8% buffered formalin solution. Paraffin embedded tissue was cut into 10-micron-thick sections parallel to the nerve longitudinal axis and stained with hematoxilin & eosin. Each of the nerves showed the presence of a zone of oligodendrocyte myelination, mean length 2 +/- 0.3 mm. In 17 nerves the transitional zone formed a cone-like process, in 4 nerves was shaped irregularly. The length of REZ (oligodendrocyte myelination plus "glial dome") had the mean length 3.5 +/- 0.9 mm.

Adult↗
PubMed1998

Cadmium content in human kidney and hair in the Gdańsk region.

Concentrations of cadmium were determined in the renal cortex and hair of 67 persons who died between 1996 and 1997 in the Gdańsk region of Poland. The mean concentrations in the renal cortex and the hair were: 39.8 +/- 21.45 micrograms/g and 0.35 +/- 0.33 microgram/g, respectively. The mean age of the population studied was 47.6 +/- 15.8 years. The concentration of cadmium in the renal cortex was age-dependent. In the age groups: 18-30, 31-40, 41-50, 51-60 and 61-90 it amounted to: 19.1 +/- 11.0 micrograms/g, 43.3 +/- 21.6 micrograms/g, 47.9 +/- 20.8 micrograms/g, 41.5 +/- 20.4 micrograms/g and 33.6 +/- 18.0 micrograms/g, respectively. No correlation between the cadmium contents in the renal cortex and hair has been established. Hair is not a good indicator of exposure to cadmium.

Adolescent↗
PubMed1997

Methods for assessing the extent of exposure and effects of air pollution.

BACKGROUND AND OBJECTIVES: In many places in Europe, the ambient air pollution exceeds the levels considered to be safe for health. The objective of the paper is to review and summarise the methods of assessment of its impact on health, and to indicate the contributions of various research disciplines, particularly environmental epidemiology. METHODS: The framework for assessment of impact is based on a four stage model: assessment of release of pollutant; assessment of exposure; assessment of the consequence; and risk estimation. RESULTS: Epidemiology is crucial in providing the data for the assessment of consequence. The criteria that determine the use of epidemiological studies for this task include lack of bias, correct control of confounding, and measured estimates of exposure. At present, those criteria are easier to satisfy for studies of short term effects on health than for the delayed consequences of exposure, or exposure accumulated over a prolonged period. Combinations of results from various populations through meta-analysis of existing studies or conducting multicentre studies is often necessary to increase the reliability of the consequence assessment stage. CONCLUSION: To assess the impact on health systematically helps to focus on actions to limit air pollutants with the greatest impacts on human health and on the most affected populations. This method allows identification of the most pertinent questions which have to be answered by studies on relations between pollution and health and on exposure of populations to air pollutants. Epidemiology has considerable potential to contribute to this research.

Air Pollutants↗
PubMed1997

Diurnal variation of PEF and its use in epidemiological studies.

Diurnal variability in peak expiratory flow (PEF) has been an accepted clinical method in the management of asthma and the evaluation of occupational asthma. In this paper, the basis for this usage together with other clinical and epidemiological applications is discussed. The measured characteristics of PEF diurnal variability are described in asthmatics and asymptomatic subjects, showing the greater variability in asthmatics, and the "morning dip" related to circadian rhythm. PEF measured by pneumotachograph and the mini-Wright meter are shown to be in good agreement, but PEF measured by the latter and other small PEF meters is different in terms of absolute values, and both intraindividual variability within test sets and diurnally. The use of PEF meters, and the daily diaries in which the subject or patient records PEF and related factors are described.

Adolescent↗