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101.
Diabetes mellitus is a metabolic disease characterized by inadequate secretion of insulin. Polyamine oxidase (PAO), a FAD-containing enzyme is involved in the biodegradation of Sp and Spd, catalyzing the oxidative deamination of Sp and Spd, resulting in production of amonia (NH3), corresponding amino aldehydes and H2O2. Malondialdehyde (MDA) and acrolein (CH2=CHCHO), potentially toxic agents, which induce oxidative stress in mammalian cells, are then spontaneously formed from aminoaldehydes. The main signs of oxidative stress in diabetic children were the values of HbA1c and MDA levels. Polyamines have an insulin-like action. Antiglycation property of spermine and spermidine has been recently confirmed. There are no data in the literature about plasma polyamine oxidase (PAO) activities in children with type 1 diabetes. The idea of this study was to evaluate the polyamine metabolism through the estimation of polyamine oxidase activity. We have study children with newly diagnosed type 1 diabetes mellitus (n = 35, age group of 5–16 years, as well as age-matched healthy control subjects (n = 25). The biochemical investigations were done on diabetic children who have the pathological values of glucose (9.11–17.33 mmol/l) and glycosylated Hb (7.57–14.49% HbA1c). The children in the control group have referent values of glucose and glycated hemoglobin (4.11-5.84 mmol/L and HbA1c 4.22-6.81% of the total Hb. Glucose levels in blood plasma and glycosylated hemoglobin in erythrocythes hemolysates (HbA1c) were measured by using standard laboratory methods. PAO activity in venous blood plasma and the amount of malondialdehyde (MDA) were measured by the spectrophotometric methods. PAO activity, glycemia, HbA1c and MDA were significantly increased in diabetic children compared to the control subjects. PAO activity in children with type 1 diabetes mellitus was very high. The findings of higher blood HbA1C and MDA levels confirm the presence of oxidant stress in children with type 1 diabetes mellitus and demonstrate that PAO activity may participate in these circumstances.  相似文献   
102.
The purpose of this investigation was to determine the atherosclerotic changes in patients with vascular parkinsonism and in patients with idiopathic Parkinson's disease, in order to evaluate the possible influence of the extracranial pathology of carotid arteries in developing lacunar cerebral infarcts. Degree of stenosis and plaque morphology of the extracranial part of carotids in both group of patients were evaluated by color Doppler flow imaging ultrasound investigation and the results were compared. We selected two matched groups of patients with parkinsonism: 22 patients with vascular parkinsonism, and 28 with idiopathic Parkinson's disease.The atherosclerotic changes found in patients with Parkinson's disease showed mild carotid lesions with mostly stable calcified plaques and lesser risk for embolic cerebral intravascular events contrary to the higher degree of carotid stenosis found in patients with vascular parkinsonism with mostly mixed plaques prone to embolization. Therefore, we suggest performing ultrasonographic examination of the extracranial part of carotid arteries in all patients with parkinsonism to assess risk of vascular accidents originating from carotid lesions. That would enable adequate treatment of parkinsonism and prevent further occurrence of intracranial vascular changes.  相似文献   
103.
Optical spectrum of the sunlight consists of visible or chromatic spectrum, with the range of wavelengths of electromagnetic vibrations from 7700 to 3900 AU, and the invisible spectrum: infrared and ultraviolet. Chromatic spectrum gives rise to the sensation of colour, capable for simulating specialized retinal photoreceptors and is perceptible as light. This rule of perception of the particular range of the optical spectrum goes mainly for man, while particular deviations, more or less, are applicable to the rest of animal and plant life. The optical part of the spectrum belongs to nonionizing radiation. It created the life on the Earth, maintaining it nowadays and even threatening the human organ of vision, because the retina had not been yet adequately accommodated through evolution with its photoreactive metabolism. Human retina is very sensitive about possible harmful influence of ultraviolet and blue light even today in evolution, but also phototoxic on complete strong visible light. In their clinical and experimental work on animals, the authors prove with their own patent (P 20020077A)-Vojnikovi? B&D, and in collaboration with Essilor Optic Austria GmbH, that particular medical filters in the range of green-yellow colour especially (565 to 570 nm), and in combination with "Transitions" successfully threat macular degeneration-AMD, slowing down its progression and having positive psychoorganic effect on the depressive mood of such patients with threatened sight. Full attention has been paid to the design of medical filter, so the periphery of the lens plays a positive role in blood concentration of melatonin, while the central part stimulates the sight and the concentration of serotonine. Thus the physiological balance of melatonin and serotonin and the stability of psychophysical disturbances have been achieved.  相似文献   
104.
Myocardial depression after cardiac surgery is modulated by cardiopulmonary bypass (CPB) and the underlying heart disease. The sodium pump is a key component for myocardial function. We hypothesized that the change in sodium pump expression during CPB correlates with intraoperative and postoperative laboratory and clinical parameters in neonates and children with various congenital heart defects. Sodium pump isoforms alpha1 (ATP1A1) and alpha3 (ATP1A3) mRNA expression in right atrial myocardium, excised before and after CPB, was quantified. Groups were assigned according to presence (VO group, n = 8) or absence (NO group, n = 8) of right atrial volume overload. CPB and aortic clamp time correlated with postoperative troponin-I values and ICU stay. ATP1A1 (P = 0.008) and ATP1A3 (P = 0.038) mRNA expression were significantly reduced during CPB. Longer aortic clamp times were associated with lower postoperative ATP1A1 (P = 0.045) and ATP1A3 (P = 0.002) mRNA expression. Low postoperative ATP1A1 (P = 0.043) and ATP1A3 (P = 0.002) expressions were associated with high troponin-I values. These results were restricted to the VO group. No correlation of sodium pump mRNA expression was found with the duration of ICU stay or ventilation. The postoperative troponin-I and clinical parameters correlated with the length of CPB, regardless of volume overload. In contrast, only dilated right atrium seemed to be susceptible to CPB in terms of sodium pump expression, showing a reduction during the operation and a correlation of sodium pump with postoperative troponin-I values.  相似文献   
105.
We are currently facing an unprecedented level of public interest in research on embryonic stem cells, an area of biomedical research that until recently was small, highly specialized and of limited interest to anyone but experts in the field. Real and imagined possibilities for the treatment of degenerative and other diseases are of special interest to our rapidly ageing population; real and imagined associations of stem cells to cloning, embryos and reproduction stir deeply held beliefs and prejudices. The conjunction of these factors could explain the recent sudden interest in embryonic stem cells but we ought to remember that this research has a long and convoluted history, and that the findings described today in the scientific and popular press are firmly grounded in research that has been going on for several decades. Here I briefly recapitulate this fascinating history.  相似文献   
106.
Despite a more than 20-year experience of therapeutic benefit, the relevant molecular and cellular targets of intravenous immunoglobulin (IVIg) in autoimmune disease remain unclear. Contrary to the prevailing theories of IVIg action in autoimmunity, we show that IVIg drives signaling through activating Fc gamma receptors (Fc gammaR) in the amelioration of mouse immune thrombocytopenic purpura (ITP). The actual administration of IVIg was unnecessary because as few as 10(5) IVIg-treated cells could, upon adoptive transfer, ameliorate ITP. IVIg did not interact with the inhibitory Fc gammaRIIB on the initiator cell, although Fc gammaRIIB does have a role in the late phase of IVIg action. Notably, only IVIg-treated CD11c+ dendritic cells could mediate these effects. We hypothesize that IVIg forms soluble immune complexes in vivo that prime dendritic-cell regulatory activity. In conclusion, the clinical effects of IVIg in ameliorating ITP seem to involve the acute interaction of IVIg with activating Fc gammaR on dendritic cells.  相似文献   
107.
MOTIVATION: Probabilistic graphical models have been developed in the past for the task of protein classification. In many cases, classifications obtained from the Gene Ontology have been used to validate these models. In this work we directly incorporate the structure of the Gene Ontology into the graphical representation for protein classification. We present a method in which each protein is represented by a replicate of the Gene Ontology structure, effectively modeling each protein in its own 'annotation space'. Proteins are also connected to one another according to different measures of functional similarity, after which belief propagation is run to make predictions at all ontology terms. RESULTS: The proposed method was evaluated on a set of 4879 proteins from the Saccharomyces Genome Database whose interactions were also recorded in the GRID project. Results indicate that direct utilization of the Gene Ontology improves predictive ability, outperforming traditional models that do not take advantage of dependencies among functional terms. Average increase in accuracy (precision) of positive and negative term predictions of 27.8% (2.0%) over three different similarity measures and three subontologies was observed. AVAILABILITY: C/C++/Perl implementation is available from authors upon request.  相似文献   
108.
Examination of cadmium (Cd) toxicity and disulfiram (DSF) effect on liver was focused on oxidative stress (OS), bioelements status, morphological and functional changes. Male Wistar rats were intraperitoneally treated with 1?mg CdCl2/kg BW/day; orally with 178.5?mg DSF/kg BW/day for 1, 3, 10 and 21 days; and co-exposed from 22nd to 42nd day. The co-exposure nearly restored previously suppressed total superoxide dismutase (SOD), catalase (CAT) and increased glutathione peroxidase (GPx) activities; increased previously reduced glutathione reductase (GR) and total glutathione-S-transferase (GST) activities; reduced previously increased superoxide anion radical (O2·?) and malondialdehyde (MDA) levels; increased zinc (Zn) and iron (Fe), and decreased copper (Cu) (yet above control value), while magnesium (Mg) was not affected; and decreased serum alanine aminotransferases (ALT) levels. Histopathological examination showed signs of inflammation process as previously demonstrated by exposure to Cd. Overall, we ascertained partial liver redox status improvement, compared with the formerly Cd-induced impact.  相似文献   
109.
110.
Reversible inhibition of conidiogenesis occurred when lecithin was depleted from Neurospora membranes by choline starvation.  相似文献   
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