The post-adipocytic phase of the adipose cell cycle.

Subcutaneous white adipose tissue harvested by liposuction has been studied with the aim to understand how the adipocytes modify their morphology when subjected to the passage in a needle for liposuction and to cryopreservation. The work try to clarify the ultrastructural aspects of adipose tissue, in the conditions described before, examining samples of body fat employed in fat graft procedures, and samples after cryopreservation. Scanning and transmission electron microscopy show that the first event that occur in the adipocytes is a lesion of mild degree detectable early in the samples fixed immediately after liposuction. The sequence of events following the adipocyte stress appeared composed by different phases: plasmatic membrane interruption, loss of lipid charge, formation of cup-like adipocytes and formation of post-adipocytes (i.e. cells that survive to traumatic events and restart to internalize lipid droplets). In conclusion, the study suggests that the loss of lipid charge in adipose cell is an active process that can be due to a small hole in the cytoplasmic membrane with the preservation of a large part of the cytoplasmatic content and that at the end of the process of lipid extrusion the cell can maintain viability.

Experimental therapies for repair of the central nervous system: stem cells and tissue engineering.

Several stem cell-based therapeutic tools are currently being investigated for the regeneration of central nervous system (CNS) injuries. This review focuses on innovative approaches for CNS tissue repair via the use of implantable cellular devices. These devices are supported by biopharmaceuticals and conventional physiotherapy for the restoration of lost neuronal circuits and CNS function. This paper further reviews new and promising tools currently in pre-clinical and clinical tests for the treatment of CNS diseases where substantial loss of cellular and extracellular components of neural tissue has occurred such as stroke, encephalopathy and traumatic neural injuries. We also discuss selected 3D bioscaffolds co-cultured with clinically applicable human mesenchymal stem cells. Recent advances in neural tissue engineering and stem cell differentiation methods have shown promise for their clinical application in treating yet incurable CNS deficits.

New perspectives in stem cell research: beyond embryonic stem cells.

Although stem cell research is a rather new field in modern medicine, media soon popularized it. The reason for this hype lies in the potential of stem cells to drastically increase quality of life through repairing aging and diseased organs. Nevertheless, the essence of stem cell research is to understand how tissues are maintained during adult life. In this article, we summarize the various types of stem cells and their differentiation potential in vivo and in vitro. We review current clinical applications of stem cells and highlight problems encountered when going from animal studies to clinical practice. Furthermore, we describe the current state of induced pluripotent stem cell technology and applications for disease modelling and cell replacement therapy.

Function of ID1 protein in human cord blood-derived neural stem-like cells.

The effect of dominant-negative regulator of basic helix-loop-helix (bHLH) transcription factors, an ID1 protein, on growth and differentiation of neural stem-like cell line derived from human umbilical cord blood (HUCB-NSC) was investigated. This nontransformed, mesodermal germ layer-originated line contains high levels of ID1 protein, whose intercellular distribution reflects HUCB-NSC differentiation status. Whereas cells remained undifferentiated and self-renewing in serum-free (SF) cultures, ID1 protein, although highly expressed, did not attain cell nuclei and was localized mainly in cytoplasm. In long-term-expanded cultures of partially committed (primed) HUCB-NSC grown in a low serum concentration (LS cultures) ID1 protein became translocated toward cell nuclei. Further neuronal differentiation of the cells, either spontaneous in the presence of serum or induced by neuromorphogens (dBcAMP, RA), resulted in almost complete depletion of ID1 mRNA and protein. Accordingly, HUCB-NSC transfectants overexpressing the ID1 gene were significantly inhibited in their differentiation. Notably, only neuronal and not glial development was affected after ID1 overexpression. A similar gain-of-function effect of ID1 transfection was observed in human NSC-like line (DEV) of medullobastoma origin, which is constitutively devoid of ID1 expression. Thus, our results on HUCB-NSC confirm further its neural-specific behavior and the crucial role of ID1 protein as a potent negative regulator of neural stem cell differentiation, pointing out that this protein distribution between cytoplasmic and nuclear cell compartments can be one of the most important steps in differentiation signal transduction.

Neurogenic potential of human umbilical cord blood: neural-like stem cells depend on previous long-term culture conditions.

In vitro studies conducted by our research group documented that neural progenitor cells can be selected from human umbilical cord blood (HUCB-NPs). Due to further expansion of these cells we have established the first human umbilical cord blood-derived neural-like stem cell line (HUCB-NSC) growing in serum-free (SF) or low-serum (LS) medium for over 3 years. The purpose of the study was to evaluate the neurogenic potential of HUCB-NSCs cultured in SF and LS condition in different in vitro settings before transplantation. We have shown that the number of cells attaining neuronal features was significantly higher for cultures expanded in LS than in SF condition. Moreover, the presence of neuromorphogens, cultured rat astrocytes or hippocampal slices promoted further differentiation of HUCB-NSCs into neural lineage much more effectively when the cells had derived from LS cultures. The highest response was observed in the case of co-cultures with rat primary astrocytes as well as hippocampal organotypic slices. However, the LS cells co-cultured with hippocampal slices expressed exclusively a set of early and late neuronal markers whereas no detection of cells with glial-specific markers was possible. In conclusion, certain level of stem/progenitor cell commitment is important for optimal response of HUCB-NSC on the neurogenic signals provided by surrounding environment in vitro.

Human cord blood-derived neural stem cell line--possible implementation in studying neurotoxicity.

Neural stem cell line developed from human umbilical cord blood (HUCB-NSC) [Buzanska et al., 2003. Journal of Neurochemistry 85, 33] is an ethically uncontroversial source of stem cells, able to differentiate into neuronal, astrocytic and oligodendroglial lineages. Developmental fate decisions of HUCB-NSC can be experimentally manipulated in vitro by the presence of trophic factors, mitogenes and neuromorphogenes, but can also be influenced by neurotoxins. In this report two-dimensional (2-D) and three-dimensional (3-D) HUCB-NSC cultures are introduced as useful models for testing developmental neurotoxicity. For 2-D culture models we established a standardized method for the assessment of the growth rate and cell differentiation in 96-well plates. The proliferative capacity of the HUCB-NSC was monitored by the MTT test while their ability to differentiate into neural-like cells by immunocytochemistry of beta-tubulin III and MAP-2 for neurons, GFAP and S-100beta for astrocytes and GalC for oligodendrocytes. The 3-D culture of HUCB-NSC is represented by neurospheres. Proliferation and migration of the intermediate precursors from attached neurospheres are shown to be controlled and altered by various growth factors and further modulated by the extracellular matrix component-fibronectin. Thus, neurospheres derived from the HUCB-NSC line can represent a suitable model of the activation of dormant stem cells residing in their niche, and can be used for neurotoxic studies.

[Preliminary assessment of occupational exposure to Glutaraldehyde in selected endoscopic workplaces]. / Wstepna ocena narazenia zawodowego na aldehyd glutarowy w wybranych pracowniach endoskopowych.

The effect of occupational exposure to glutaric aldehyde in 17 endoscopic laboratories of the Wroclaw 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.

[Problems of environmental exposure to toxic effects of glutaraldehyde in medicine]. / Problemy zawodowego narazenia na toksyczne dzialanie aldehydu glutarowego w medycynie.

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.

[Role of selenium in human pathophysiology]. / Rola selenu w patofizjologii czlowieka.

Paper describes selenium metabolism and its function in physiological and pathological states. A role of selenium in development of human internal pathology with its action in suppressing the carcinogenesis is outlined. Function of selenium in biochemical structures is showed with a special stress put on glutathione peroxidase.

[Free radicals and their importance in medicine]. / Wolne rodniki i ich znaczenie w medycynie.

The work presents current views of free radicals and their role in medicine. In the first fact, the chemical nature of free radicals, their reactions in cells and its consequences are discussed. The second part deals with a role of free radicals in human pathology with a special stress put an arteriosclerotic process. In the third part, the defense mechanism against free radical action, particularly the importance of superoxide dismutase.

[A free radical mechanism for inhibition of arteriosclerosis development with calcium antagonists]. / Wolnorodnikowe mechanizmy hamowania rozwoju miazdzycy przez antagonistów wapnia (ACa).

Work presents current views on involvement of free radicals in inhibition of development of arteriosclerosis by calcium antagonist (ACa). The importance of other substances, which interferes with calcium ions can contribute to the inhibition of arteriosclerosis development.

[Effect of enalapril and terazosin on lipid metabolism in patients with essential arterial hypertension and accompanying hypercholesterolemia]. / Wplyw enalaprilu i terazosyny na gospodarke lipidowa u chorych z pierwotnym nadcisnieniem tetniczym i towarzyszaca hipercholesterolemia.

The effect of enalapril and terazosin on serum lipid profile was investigated in 36 patients with primary hypertension and hypercholesterolemia (total cholesterol 5.2 mmol l). 6- and 12-week monotherapy with these drugs did not produce any unfavourable changes in: total cholesterol, LDL- and HDL-cholesterol, triglycerides, apolipoproteins A1 and B as well as in serum lipids. Enalapril and terazosin seem to be very useful as a first step monotherapy especially in patients with hypertension and lipid disturbances.

[Echocardiographic test of dipyridamole in recognition of coronary artery disease]. / Echokardiograficzna próba dipirydamolowa w rozpoznawaniu choroby niedokrwiennej serca.

To assess the feasibility, safety and usefulness of dipyridamole stress echocardiography for the detection of coronary artery disease we evaluated 194 patients (124 men, 70 women) with effort chest pain. All patients underwent electrocardiographic submaximal bicycle exercise testing and 2-dimensional echocardiography after dipyridamole injection. Echocardiographic test was considered positive when new wall motion abnormalities were observed after dipyridamole i.v. injection (0.56 mg/kg b.m.). Sensitivity and specificity of electrocardiographic exercise test and dipyridamole stress echocardiography were assessed in 37 persons who underwent selective coronary angiography. The sensitivity and specificity of dipyridamole stress echocardiography, were respectively 85.0% and 91.7% and were higher than those of exercise electrocardiography. 2-dimensional echocardiography after dipyridamole injection is a well tolerated, feasible and effective test in the diagnosis of coronary artery disease.

[Examination of the usefulness of echocardiography with dobutamine for diagnosis of coronary disease]. / Badania nad przydatnoscia echokardiograficznej próby dobutaminowej w rozpoznawaniu choroby niedokrwiennej serca.

To assess the feasibility, safety and usefulness of dobutamine stress echocardiography for the detection of coronary artery disease we evaluated 63 patients (45 men, 18 women) with effort chest pain. All patients underwent electrocardiographic submaximal bicycle exercise testing and 2-dimensional echocardiography during dobutamine infusion. Echocardiographic dobutamine test response was considered positive when new wall motion abnormalities were observed during dobutamine infusion. Sensitivity and specificity of electrocardiographic exercise test and dobutamine stress echocardiography were assessed in 25 patients who underwent selective coronary angiography. The sensitivity and specificity of dobutamine stress echocardiography, respectively 93.3% and 83.3%, were higher than those of exercise electrocardiography. 2-dimensional echocardiography during dobutamine infusion is a well tolerated, feasible and effective test for detecting coronary artery disease.