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Journal Article 2007; 28(4): 367-381 PubMed PMID: 17693980 Citation  Keywords:  Aged, Case-Control Studies, Critical Illness:therapy, Female, Humans, Lipid Peroxidation:physiology, Male, Middle Aged, Oxidation-Reduction, Oxidative Stress:physiology, Regression Analysis, Treatment Outcome, Triiodothyronine:blood,.   

OBJECTIVES: Increased oxidative stress and low-T3 syndrome may develop in critically ill patients. The study aimed at evaluating the level of lipid peroxidation (LPO) in critically ill patients and at estimating the relationships among LPO level, the death rate, the rate of low-T3 syndrome and patient's clinical status.

METHODS: Lipid peroxidation (LPO) level was studied in seventy (70) adult, critically ill patients and 48 healthy volunteers. Critically ill patients were classified into survivors and non-survivors, or those with and without the low-T3 syndrome (normal-T3).

RESULTS: LPO level was four times higher in critically ill patients than in healthy volunteers. Among non-survivors, LPO level was higher in patients with the low-T3 syndrome than in patients without this syndrome, and among survivors, the tendency was opposite. Additionally, the extent, to which LPO level increased, depended on the kind of the disease. The degree of LPO variability was higher in survivors than in non-survivors. LPO level was lower in patients with higher number of therapeutic interventions.

CONCLUSION: A tremendous increase in oxidative damage to lipids in critically ill patients strongly depends on the kind of pathological process and, under certain conditions, higher LPO levels could be due to more favourable outcome....

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Journal Article 2007; 28(4): 456-462 PubMed PMID: 17693979 Citation  Keywords:  Adult, Case-Control Studies, Cell Nucleus:physiology, Fatigue Syndrome, Chronic:metabolism, Female, Humans, Inflammation:metabolism, Lymphocytes:drug effects, Male, Middle Aged, NF-kappa B:metabolism, Neurasthenia:physiopathology, Oxidative Stress:physiol.   

: There is now some evidence that chronic fatigue syndrome is accompanied by an activation of the inflammatory response system and by increased oxidative and nitrosative stress. Nuclear factor kappa beta (NFkappabeta) is the major upstream, intracellular mechanism which regulates inflammatory and oxidative stress mediators. In order to examine the role of NFkappabeta in the pathophysiology of CFS, this study examines the production of NFkappabeta p50 in unstimulated, 10 ng/mL TNF-alpha (tumor necrosis factor alpha) and 50 ng/mL PMA (phorbolmyristate acetate) stimulated peripheral blood lymphocytes of 18 unmedicated patients with CFS and 18 age-sex matched controls. The unstimulated (F=19.4, df=1/34, p=0.0002), TNF-alpha-(F=14.0, df=1/34, p=0.0009) and PMA-(F=7.9, df=1/34, p=0.008) stimulated production of NFkappabeta were significantly higher in CFS patients than in controls. There were significant and positive correlations between the production of NFkappabeta and the severity of illness as measured with the FibroFatigue scale and with symptoms, such as aches and pain, muscular tension, fatigue, irritability, sadness, and the subjective feeling of infection. The results show that an intracellular inflammatory response in the white blood cells plays an important role in the pathophysiology of CFS and that previous findings on increased oxidative stress and inflammation in CFS may be attributed to an increased production of NFkappabeta. The results suggest that the symptoms of CFS, such as fatigue, muscular tension, depressive symptoms and the feeling of infection reflect a genuine inflammatory response in those patients. It is suggested that CFS patients should be treated with antioxidants, which inhibit the production of NFkappabeta, such as curcumin, N-Acetyl-Cysteine, quercitin, silimarin, lipoic acid and omega-3 fatty acids....

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Journal Article 2007; 28(3): 311-314 PubMed PMID: 17627268 Citation  Keywords:  Blood Pressure, Creatinine:blood, Female, Homocysteine:blood, Humans, Hypertension, Pregnancy-Induced:blood, Lipofuscin:blood, Oxidative Stress, Peptides:blood, Pregnancy,.   

OBJECTIVE: The aim of this study were to assess the levels of lipofuscin (parameter of oxidative stress), homocysteine (as a marker of vascular injury) and tissue specific antigen - TPS - (as a marker of cell proliferation) in relation to arterial pressure of pregnant woman.

STUDY DESIGN: Healthy pregnant women (n=18), women with mild 140/90=< RR<160/100 (n=19), and severe 160/100=
RESULTS: Mean duration of gestation was 34+/-5 weeks, and there were no differences between groups. Serum lipofuscin levels in mild form of pregnancy-induced hypertension were decreased comparing to normal pregnancy. Homocysteine levels were decreased and TPS levels increased in both mild and severe gestational hypertension.

CONCLUSION: Our results suggest overestimation of the role of oxidative stress and hyperhomocysteinemia in gestational hypertension....

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Journal Article 2007; 28(3): 267-273 PubMed PMID: 17627260 Citation  Keywords:  Acetamides:pharmacology, Animals, Autoradiography, Binding Sites, Brain:metabolism, Circadian Rhythm, Female, Melatonin:metabolism, Memory, Receptors, Melatonin:analysis, Stress, Psychological:physiopathology, Suprachiasmatic Nucleus:chemistry, Tupaiidae,.   

OBJECTIVE: In this study we investigated the distribution of melatonergic receptors in the tree shrew brain. The psychosocial stress in the tree shrew is a validated model of depression with disturbance of circadian rhythms.

METHODS: Given the role of melatonin in the modulation of circadian rhythms, we determined by autoradiography the distribution of binding sites of 2-[125I]-MLT, a ligand for the two melatonergic receptors MT1 and MT2, in the tree shrew brain focusing mostly on the suprachiasmatic nucleus (SCN), the biological clock involved in resynchronization of circadian rhythms. We also analyzed the distribution of 2-[125I]-MLT in other brain areas involved in regulation of mood.

RESULTS: Specific binding of 2-[125I]-MLT was found in the SCN. In addition, several structures in the tree shrew brain were labeled, among them the pars tuberalis, the cerebellum, structures of the hippocampal formation and dopaminergic areas such as the caudate putamen and nucleus accumbens, providing other potential targets of psychosocial stress in the tree shrew, in addition to the SCN.

CONCLUSIONS: The demonstration of melatonergic receptors in these brain areas supports their probable involvement in the behavioural, neuroendocrine and circadian rhythms disturbances observed in the psychosocial stress model of depression in the tree shrew....

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Journal Article 2006; 27(6): 807-812 PubMed PMID: 17187012 Citation  Keywords:  Animals, Cell Differentiation:physiology, Cell Line, Tumor, Cell Shape, Mice, Neuroblastoma, Neurons:cytology, Neuroprotective Agents:administration & dosage, Oxidative Stress:physiology, Stem Cells:cytology, Testosterone:administration & dosage, Tyrosine.   

OBJECTIVES: Using undifferentiated mouse neuroblastoma cells (C1300), we have previously observed that testosterone (T) exerts a neuroprotective action against oxidative stress. Nitrogen intermediates induce the production of 3-nitro-L-tyrosine (3NT), an amino acid analogue involved in many neurodegenerative disorders. The aim of our work is to investigate T capability on C1300 cell differentiation. It is also evaluated whether differentiation could mitigate the nitrosative effects of 3NT.

METHODS: The effects of both T and 3NT were studied on an undifferentiated cell line of neural origin (C1300). For this purpose, cell cultures underwent morphometric investigation, blot analyses and catalase activity assay. All data obtained were expressed as mean+/-SD and tested by one-way ANOVA or Student's t test.

RESULTS: The results were compared with those gathered by means of N6,2'-O-dibutyryl-adenosine-3',5'-cyclic-mono-phosphate (db-cAMP), a well-known differentiating agent. T-exposed cells showed an irregular shape and exhibited long branching cytoplasmic extensions, which were longer than in db-cAMP cells. Moreover, T-exposure induced an increase in the expression of tyrosinated and acetylated alpha-tubulin while 3NT-incorporation into tubulin was markedly reduced. The action of antioxidant defence systems, namely catalase activity, was enhanced in cells exposed to T.

CONCLUSION: This work highlighted the effects of db-cAMP on differentiation and neuroprotection, but even indicated that T exposure induced differentiation in C1300 cells and this process matches a significant neuroprotective effect. This action seemed to be more effective than in db-cAMP-treated cells. T is suggested, like other substances having antioxidant properties, to be of potential interest in the experimental therapy of neuropathological conditions....

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Comparative Study 2006; 27(Suppl 2): 112-115 PubMed PMID: 17159793 Citation  Keywords:  Adult, Aged, Aged, 80 and over, DNA Damage, Diet, Female, Fruit, Humans, Male, Malondialdehyde:blood, Middle Aged, Mineral Fibers:toxicity, Occupational Diseases:prevention & control, Oxidative Stress, Vegetables, Vitamins:blood,.   

OBJECTIVES: In humans, epidemiological evidence suggests that increased consumption of fruits and vegetables can substantially enhance the protection against many common types of cancer.

METHODS & RESULTS: A molecular epidemiological study in 3 Slovak factories producing asbestos, glass fibres and rockwool was conducted. Altogether 388 subjects (239 exposed, 148 controls) were investigated. Food frequency questionnaire was used to ascertain nutrient intake and compared to plasma levels of selected micronutrients, as well as to markers of oxidative stress (MDA, oxidative DNA damage and DNA repair) and antioxidant protection. We found a negative correlation between MDA concentrations and consumption of fruits (p=0.05) and vegetables (p=0.05) in all control subjects. Intake of fruits (p=0.05), vegetables (p=0.01), milk (p=0.01) and cereals (p=0.05) inversely correlated with oxidative DNA damage (net FPG) in all subjects investigated. There was a negative correlation between the intake of fruits (p=0.05) and vegetables (p=0.01) in all exposed subjects.

CONCLUSIONS: Our results suggest that well balanced food consumption with higher fruits and vegetables intake has a protective effect against oxidative damage....

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Comparative Study 2006; 27(Suppl 2): 65-68 PubMed PMID: 17159782 Citation  Keywords:  Asphyxia Neonatorum:blood, Delivery, Obstetric, Glutathione Peroxidase:blood, Humans, Infant, Newborn, Malondialdehyde:blood, Oxidative Stress, Stress, Physiological:blood, Superoxide Dismutase:blood, Term Birth:blood,.   

OBJECTIVES: In healthy term newborns (HTN) to determine on the 1st and 5th day of life the activity of total antioxidant capacity (TAS), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPX) and to compare the values with the group of asphyxiated term newborns (ATN).

PATIENTS/METHODS: The series consisted of 15 HTN and 24 ATN. In both groups TAS, MDA, GPX and SOD were investigated.

RESULTS: Reference values in HTN (1st/5th day of life) for TAS were 0.52+/-0.03/0.49+/-0.04 mmol/l, for MDA 0.72+/-0.07/1.08+/-0.09 micromol/l, for SOD 594.20+/-16.47/591.23+/-14.14 Ug/Hb and for GPX 25.48+/-1.32/25.98+/-1.20 Ug/Hb. In a group of ATN the obtained values were (1st/5th day of life): TAS 1.1+/-0.08/0.98+/-0.08 mmol/l, MDA 2.08+/-0.22/2.21+/-0.34 micromol/l, SOD 509.18+/-26.8/564.49+/-36.4 Ug/Hb and GPX 30.2+/-1.9/32.45+/-2.69 Ug/Hb.

CONCLUSIONS: Statistically significant differences were found on the 1st and 5th day of life between the two groups investigated in values of MDA (**p<0.01) and TAS (**p<0.01). Increased values of MDA in the group of ATN on the 1st and 5th day of life confirmed the presence of lipoperoxidation. The obtained values of TAS on the 1st and 5th day of life in the group of ATN were surprisingly higher than in HTN. The increase of TAS in ATN could point to a certain ability of ATN to prevent the damage of balance between overproduction of MDA and antioxidants. The results of SOD and GPX activity were not statistically significant, yet they are indicative of the biochemical reaction of the organism of term newborns to asphyxia....

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Comparative Study 2006; 27(5): 669-674 PubMed PMID: 17186998 Citation  Keywords:  Adolescent, Adult, Educational Measurement:methods, Exploratory Behavior, Female, Humans, Hydrocortisone:analysis, Male, Saliva:chemistry, Stress, Psychological, Students:psychology,.   

OBJECTIVE: In the present study we evaluated whether intensity and novelty of oral academic examinations are reflected in saliva cortisol titre.

DESIGN AND SETTING: 91 pupils completed questionnaires on sensation seeking according to Zuckerman as well as on stress coping strategies and rated their individual stress intensity upon minor oral examinations. 26 of these students donated saliva samples before as well as ten and 30 minutes after the examination to quantify cortisol using an immuno assay. Oral examinations during the school year, where students may re-adjust their grade on subsequent examinations, were regarded as minor oral examinations, whereas school exit examinations, where students do not have the chance to correct their grade anymore and may even risk a delay of several months in their academic career when they fail, were regarded as major examinations.

RESULTS: Minor oral examinations revealed either a moderate, but significant, increase in saliva cortisol titre by 1.1 fold or did not have a significant impact on cortisol titre. In contrast, school exit exams elevated cortisol titre 5.2 fold. In minor oral examinations, moderate correlations between cortisol titre and subsets in sensation seeking and coping strategies, respectively, were identified.

CONCLUSION: Intensity and novelty of an academic examination is significantly correlated to cortisol titre. Minor oral examinations, with little consequences on academic career, only have a minor impact on cortisol titre, whereas school exit examinations, which are novel to students and may have major consequences on the academic career, elicit a major increase in cortisol titre....

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