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1.
We investigated the effects of treadmill exercise performed regularly for 6 weeks on the levels of nerve growth factor (NGF), tyrosine kinase A and p75 receptors, phosphatidylinositol 3-kinase (PI3-K), mitogen-activated protein kinase/extracellular signal-regulated kinase (Erk) 1,2, cyclic AMP response element-binding protein (CREB), and caspase-3 in the soleus of rats with streptozotocin (STZ)-induced diabetes. Thirty-two male Sprague–Dawley rats were divided into the following four groups: (1) normal control group (NCG; n = 8), (2) normal exercise group (NEG; n = 8), (3) diabetes control group (DCG; n = 8), and (4) diabetes exercise group (DEG; n = 8). Diabetes was induced by intraperitoneal injection of STZ (55 mg/kg dissolved in 0.05 M citrate buffer, pH 4.5). Rats were subjected to treadmill exercise 5 days a week for 6 weeks. The protein level of NGF significantly increased in the NEG and DEG (p < 0.001), whereas the levels of tyrosine kinase A and p75 receptors significantly increased in the NEG (p < 0.001). The levels of t-PI3-K, p-PI3-K, and p-CREB, and the p-CREB/t-CREB ratio significantly increased in the NEG (p < 0.001, respectively). The p-PI3-K/t-PI3-K ratio significantly increased in the DEG (p < 0.001). The p-Erk1/t-Erk1 ratio significantly increased in the NEG (p < 0.001), whereas the p-Erk2/t-Erk2 ratio significantly decreased in the DCG and DEG (p < 0.001). The caspase-3 level significantly increased in the DCG compared with that in the DEG (p < 0.001). These results suggest that treadmill exercise increases NGF levels and accelerates p-PI3-K activation in order to suppress apoptotic cell death in the soleus muscle of diabetic rats.  相似文献   

2.
Monocyte-extracellular matrix interactions have been implicated in atherosclerosis pathophysiology. Laminin, the main basement membrane protein contains cell binding domains that can be cryptic, presented only after protein modification. In the present study we evaluated monocyte attachment to laminin-1 in the presence of ATP. Monocytes were derived from either healthy volunteers or patients with diabetes mellitus type II. For the estimation of monocyte attachment to laminin the myeloperoxidase assay was used. Monocytes derived from diabetic patients, showed an increased ability to attach to laminin (p = 0.0055). The presence of ATP increased the attachment of control monocytes to laminin (p = 0.0022). On the contrary, the presence of ATP did not affect the attachment of monocytes derived from diabetic patients to laminin. Our results indicate a modified interaction between monocytes and laminin-1 in diabetes mellitusKey words: monocytes, ATP, laminin-1, diabetes mellitus, attachment  相似文献   

3.
Dogs are the domestic reservoir of Leishmania infantum, a vector-borne intracellular protozoan agent of human visceral leishmaniasis. The role of polymorphonuclear leukocytes (PMNs) in the immune defence against this parasite has been poorly studied. We have investigated the function of peripheral blood PMNs in naive beagle dogs that have been naturally exposed to phlebotomine vectors in an area highly endemic for canine leishmaniasis, and found infected by Leishmania at the end of the transmission season. Whole blood phagocyte oxidative metabolism was assessed by a rapid method that determines a luminol-amplified chemiluminescence (CL) emission. This was evaluated using either a soluble stimulant, phorbol mirystate acetate (PMA), or phagocytic stimuli, such as zymosan unopsonized (ZYM) or opsonized with autologous serum (OPZ). In blood samples taken 2 months after exposure to Leishmania transmission, data on CL emission revealed a significant decrease of reactive oxygen intermediates (ROI) production in the presence of both PMA and ZYM, compared with blood samples obtained from dogs before exposure. On the contrary, no variations in CL emission were detected in presence of OPZ. Our data indicate that immunological changes occur early in canine leishmaniasis and confirm that the role of PMNs and their products need to be clarified. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

4.
Monocyte-extracellular matrix interactions have been implicated in atherosclerosis pathophysiology. Laminin, the main basement membrane protein contains cell binding domains that can be cryptic, presented only after protein modification. In the present study we evaluated monocyte attachment to laminin-1 in the presence of ATP. Monocytes were derived from either healthy volunteers or patients with diabetes mellitus type II. For the estimation of monocyte attachment to laminin the myeloperoxidase assay was used. Monocytes derived from diabetic patients, showed an increased ability to attach to laminin (p=0.0055). The presence of ATP increased the attachment of control monocytes to laminin (p = 0.0022). On the contrary, the presence of ATP did not affect the attachment of monocytes derived from diabetic patients to laminin. Our results indicate a modified interaction between monocytes and laminin-1 in diabetes mellitus.  相似文献   

5.
In this study neutrophil (PMN) phagocytic capacity was investigated using a conventional radiometric ingestion assay (IN) in comparison with PMN respiratory burst activity assessed by luminol-enhanced chemiluminescence (LCL) in response to phorbolesters and LCL induction during phagocytosis of opsonized Staphylococous aureus (STLCL) in diabetes mellitus and healthy controls. PMN ingestion was measured with 3H-thymidine-labelled S. aureus in a kinetic radiometric assay. LCL and STLCL were assessed in a parallel detecting microtitre-plate luminometer (MTP-Reader). PMN of diabetic subjects showed a highly significant reduction of peak LCL in response to PMA as well as during phagocytosis of S. aureus (STLCL) compared to non-diabetic controls (p<0.001 respectively). PMN ingestion in diabetic patients (51.8±4.6%) was significantly reduced compared to controls (78.3±6.2%) (p<0.01). The in vitro data displayed impaired PMN oxidative burst activity at glucose concentrations ? 13.8mmol/L, whereas PMN IN was significantly reduced at glucose levels ?27.75mmol/L. The control group showed a positive correlation of peak LCL response and IN (p<0.05) but not of STCL and IN; in diabetic patients this was also true, but did not reach statistical significance. The data obtained in this study clearly demonstrated impaired PMN respiratory burst activity and markedly reduced phagocytic PMN functions in diabetic patients ex vivo and in vitro as measured by LCL and by ingestion of 3H-thymidine-labelled S. aureus suggesting inhibitory effects of elevated glucose concentrations on various PMN-functions, which might be of clinical importance concerning altered host defence.  相似文献   

6.
The interactions between monocytes and extracellular matrix proteins have been implicated in atherosclerosis pathophysiology. In the present study we evaluated monocyte attachment and migration through oxidized and non-oxidized collagen IV. Monocyte attachment was tested on microwells coated with either native or oxidized collagen IV. Monocyte migration through collagen IV was examined on transwells. Monocytes derived from patients with diabetes mellitus showed an increased ability to attach and migrate through collagen IV as compared to those derived from healthy volunteers. Moreover, control monocytes attached to oxidized collagen at a higher degree, while they migrated through oxidized collagen at a lower degree, as compared to the native protein. Our results also showed the involvement of the alpha2 integrin subunit in the above phenomena suggesting a modified interaction between monocytes and collagen IV in diabetes mellitus.  相似文献   

7.
This study aimed to compare the trace element status of patients with type 2 diabetes (n=53) with those of nondiabetic healthy controls (n=50). The concentrations of seven trace elements were determined in the whole blood, blood plasma, erythrocytes, and lymphocytes of the study subjects. Vanadium and iron levels in lymphocytes were significantly higher in diabetic patients as compared to controls (p<0.05 for iron and p<0.01 for vanadium). In contrast, lower manganese (p<0.01) and selenium (p<0.01) concentrations were detected in lymphocytes derived from patients with type 2 diabetes versus healthy subjects. Furthermore, significantly lower chromium levels (p<0.05) were found in the plasma of diabetic individuals as compared to controls. Trace element concentrations were not dependent on the degree of glucose control as determined by correlation analysis between HBA1c versus metal levels in the four blood fractions. In summary, this study primarily demonstrated that trace element levels in lymphocytes of patients with type 2 diabetes could deviate significantly from controls, whereas, in general, no considerable differences could be found when comparing the other fractions between both patient groups. Therefore, it seems reasonable to analyze metal levels in leukocytes to determine trace element status in patients with type 2 diabetes and perhaps in other diseases.  相似文献   

8.
Human alveolar macrophages (AM) were demonstrated to generate reactive toxic derivatives of oxygen in many pulmonary disorders. These cells are involved in local inflammation which characterizes bronchial asthma. In the present work, we studied the ability of stimulated macrophages from healthy volunteers, and asthmatic patients to generate oxygen species in vitro. AM obtained by bronchoalveolar lavage were purified by adherence. The production of oxygen species was measured by luminol-enhanced chemiluminescence (CL) after challenge with opsonized zymosan. The maximal values were significantly (p < 0.03 and p < 0.01) higher in AM from asthmatics than in AM from healthy subjects. A significant correlation (p < 0.01) was observed between maximal value of CL and the severity of asthma as assessed by the clinical score. But, no difference was observed between AM from asthmatics in a stable state and healthy subjects. On the other hand, assays for superoxide anion generation emphasized the activation state of these macrophages stimulated by formyl-peptides.  相似文献   

9.
The present study was undertaken to investigate the redox status in the retina of an experimental model that combines hypertension and diabetes. Spontaneously hypertensive rats (SHR) and their control Wystar Kyoto (WKY) rats were rendered diabetic and, after 20 days, the rats were sacrificed and the retinas collected. The superoxide production was higher in diabetic than in control WKY (p<0.03) and SHR rats showed elevated superoxide production compared with WKY groups (p<0.009). The glutathione antioxidant system was diminished only in diabetic SHR (p<0.04). Tirosyne nitration was higher in diabetic WKY and control SHR compared with control WKY (p<0.03), and further increment was observed in diabetic SHR (p<0.02). The DNA damage estimated by immunohystochemistry for 8-OHdG was higher in control SHR than in WKY, mainly in diabetic SHR (p<0.0001). Hypertension aggravates oxidative-induced cytotoxicity in diabetic retina due to increasing of superoxide production and impairment of antioxidative system.  相似文献   

10.
There is accumulating evidence that the metabolism of several trace elements is altered in diabetes mellitus and that these nutrients might have specific roles in the pathogenesis and progress of this disease. The aim of present study was to compare the level of essential trace elements, chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn) in biological samples (whole blood, urine, and scalp hair) of patients who have diabetes mellitus type 2 (n = 257), with those of nondiabetic control subjects (n = 166), age ranged (45–75) of both genders. The element concentrations were measured by means of an atomic absorption spectrophotometer after microwave-induced acid digestion. The validity and accuracy was checked by conventional wet-acid-digestion method and using certified reference materials. The overall recoveries of all elements were found in the range of (97.60–99.49%) of certified values. The results of this study showed that the mean values of Zn, Mn, and Cr were significantly reduced in blood and scalp-hair samples of diabetic patients as compared to control subjects of both genders (p < 0.001). The urinary levels of these elements were found to be higher in the diabetic patients than in the age-matched healthy controls. In contrast, high mean values of Cu and Fe were detected in scalp hair and blood from patients versus the nondiabetic subjects, but the differences found in blood samples was not significant (p < 0.05). These results are consistent with those obtained in other studies, confirming that deficiency and efficiency of some essential trace metals may play a role in the development of diabetes mellitus.  相似文献   

11.
Heat shock proteins play an important role as molecular chaperones of the cell. Inducible heat shock protein 70 is rapidly synthesised in response to numerous stressors and monocytes are sensitive to changes in core temperature resulting in a circadian variation of Hsp70 expression. Monocytes were isolated via density centrifugation from nine healthy male volunteers at 5 am, 1 pm and 9 pm, representing the nadir (5 am), peak (9 pm) and intermediate (1 pm) of Hsp70 expression in the 24-h cycle. Analysis of freshly isolated monocytes for Hsp70 expression confirmed Hsp70 levels at the three selected time points. Monocytes were subjected to in vitro heat shock at 40°C (±0.1) for 90 min with a 90 min 37°C (±0.1) exposure acting as a control. A significant increase in Hsp70 was observed at 5 am (p < 0.001) and 1 pm (p = 0.028) at 40°C when compared to 37°C but not at 9 pm (p = 0.19). A significant increase was also observed from the basal levels of Hsp70, measured on freshly isolated monocytes and the levels detected after heat shock at 40°C at 5 am (p < 0.001) and 1 pm (p = 0.001), which was not observed at 9 pm (p = 0.15). Furthermore, a significant correlation was observed in the heat shock response at 40°C and that obtained at 37°C (p < 0.001). In conclusion, the heat shock response in monocytes is directly proportional to the amount of Hsp70 present in the cells and the stress response may be much higher at different times of the day.  相似文献   

12.
In order to investigate the relationships between metals zinc [Zn], copper [Cu], magnesium [Mg], or Calcium [Ca] and noninsulin-dependent diabetes mellitus, 65 patients of newly diagnosed noninsulin-dependent diabetes mellitus and 54 nondiabetic healthy controls were studied. The concentrations of selected metals in fasting blood samples and 24-h urine collections were determined. Hyperzincuria and hypermagnesuria were detected in diabetic patients (p<0.01). The diabetics also had lower Zn and Mg, and higher Cu, and Ca levels in their plasma than those of the controls, but the statistical differences in Ca and Mg were not significant.Significantly lower Zn and higher Ca levels in erythrocytes were found in diabetic patients (p<0.01). There is evidence of a significant difference in metals status between diabetic patients with or without the specific complications. This study further indicates that patients with NIDDM on Taiwan also have distinct changes in their metals status, and these perturbations are associated with some diabetic complications.  相似文献   

13.
Diabetes and stress stimulate hippocampal 5-HT synthesis, metabolism and release. The present study was carried out to find the effects of insulin, Aegle marmelose alone and in combination with pyridoxine on the hippocampal 5-HT, 5-HT2A receptor subtype, gene expression studies on 5-HT2A, 5-HTT, INSR, immunohistochemical studies and elevated plus maze in streptozotocin induced diabetic rats. 5-HT content showed a significant decrease (p < 0.001) and a significant increase (p < 0.001) in 5-HIAA in hippocampus of diabetic rats compared to control. 5-HT receptor binding parameters Bmax and Kd showed a significant decrease (p < 0.001) whereas 5-HT2A receptor binding parameters Bmax showed a significant decrease (p < 0.001) with a significant increase (p < 0.05) in Kd in hippocampus of diabetic rats compared to control. Gene expression studies of 5-HT2A, 5-HTT and INSR in hippocampus showed a significant down regulation (p < 0.001) in diabetic rats compared to control. Pyridoxine treated in combination with insulin and A. marmelose to diabetic rats reversed the 5-HT content, Bmax , Kd of 5-HT, 5-HT2A and gene expression of 5-HT2A, 5-HTT and INSR in hippocampus to near control. The gene expression of 5-HT2A and 5-HTT were confirmed by immunohistochemical studies. Behavioural studies using elevated plus maze showed that serotonin through its transporter significantly increased (p < 0.001) anxiety-related traits in diabetic rats which were corrected by combination therapy. Our results suggest that pyridoxine treated in combination with insulin and A. marmelose has a role in the regulation of insulin synthesis and release, normalising diabetic related stress and anxiety through hippocampal serotonergic function. This has clinical significance in the management of diabetes.  相似文献   

14.
Beneficial effect of vitamin E on the metabolic parameters of diabetic rats   总被引:1,自引:0,他引:1  
The role of vitamin E in the pathogenesis of diabetes mellitus is unknown. The purpose of this study was to examine the effect of oral administration of vitamin E on some of the metabolic parameters of experimental diabetic rats. Diabetes was induced by intraperitoneal injection of streptozotocin (60 mg/kg body weight at 12 weeks of age). Vitamin E (0.2, 0.4, 0.8 mg/kg body weight) was administered orally for a period of 3 weeks to normal and diabetic Wistar rats. In some experiments, Vitamin E was given either before or after the induction of diabetes mellitus. Blood glucose level and weight were recorded for each rat in different groups on a weekly basis. Oral glucose tolerance test (OGTT) was performed on fasted normal, diabetic and vitamin E treated rats at the end of the experiment. Vitamin E significantly (p < 0.01) reduced blood glucose levels in experimental diabetes mellitus at all doses as compared to untreated rats. Vitamin E induced weight loss in normal as well as in diabetic rats. The beneficial effect of vitamin E on the hyperglycaemia of diabetic rats was dose-dependent. Moreover, vitamin E also improved OGTT in diabetic rats compared to untreated diabetics. In conclusion, vitamin E may play a role in glucose metabolism and thus be a useful adjuvant therapy in type I diabetes. (Mol Cell Biochem 261: 35–42, 2004)  相似文献   

15.
Objective: Although recent studies link altered cellular redox state to protein dysfunction in various disease-states, such associations are least studied in clinical diabetes. Therefore, this study assessed the levels of reduced glutathione (GSH) and Na+/K+ ATPase activities in type 2 diabetic patients with and without microangiopathy. Methods: The study group comprised of a total of 160 subjects, which included non-diabetic healthy controls (n = 40) and type 2 diabetic patients without (n = 60) and with microangiopathy (n = 60), defined as presence of retinopathy with or without nephropathy. Erythrocyte Na+/K+ ATPase activity and GSH levels were estimated spectrophotometrically and fluorometry was used to determine the plasma thiobarbituric acid reactive substances (TBARS) and serum advanced glycation end products (AGEs). Results: GSH levels in diabetic subjects without (4.8± 0.15 μmol/g Hb) and with microangiopathy (5.2± 0.14 μmol/g Hb) were significantly lower (p < 0.001) compared to control subjects (6.3± 0.14 μmol/g Hb). Erythrocyte Na+/K+ ATPase activity was significantly reduced (p < 0.001) in diabetes subjects with (272± 7 nmol Pi/mg protein/h) and without microangiopathy (304 ± 8) compared to control (374 ± 6) subjects. TBARS were significantly higher (p < 0.001) in diabetes subjects with (10.65± 0.81 nM/ml) and without microangiopathy (9.90± 0.5 nM/ml) compared to control subjects (5.18± 0.18 nM/ml). Advanced glycation end product levels were also significantly (p < 0.001) elevated in diabetic subjects with microangiopathy (8.2± 1.8 AU) when compared to diabetes subjects without microangiopathy (7.0± 2.0 AU) and control subjects (4.6± 1.9 AU). On multivariate regression analysis, GSH levels showed a positive association with the Na+/K+ ATPase activity and negative association with TBARS and AGE levels. Conclusion: Hypoglutathionemia and increased oxidative stress appears to be early biochemical aberrations in diabetes, and through protein alterations, oxidative stress and redox modifications may contribute to pathogenesis of diabetic microangiopathy.  相似文献   

16.
Recently, fluconazole (FLZ) has been shown to improve survival and reduce multiorgan failure in experimental and clinical septic shock. The mechanism by which FLZ affords protection against sepsis remains obscure. This study examines the effect of FLZ on phagocytic activity of polymorphonuclear leukocytes (PMNs) in a rat model of septic shock by inducing fecal peritonitis in male Wistar rats using intraperitoneal instillation (1 mL/kg) of fecal suspension in saline (1:1 w/v). Sham control rats received sterile fecal suspension and vehicle treatment. FLZ was administered in the doses of 0, 3, 10, and 30 mg/kg by gavage 30 minutes before fecal instillation. The samples of peritoneal fluid were collected 8 hours following fecal inoculation for the evaluation of phagocytic response of PMNs using zymosan-induced luminol-dependent chemiluminescence (CL). Fecal peritonitis caused massive infiltration of PMNs in the peritoneal cavity (ANOVA F(4,45) = 6.322, P < .001). Although FLZ reduced the infiltration of PMNs, this effect was neither significant nor dose dependent. The actual CL response was significantly higher in the peritoneal fluid of rats subjected to peritonitis, which was significantly and dose dependently attenuated by FLZ treatment (ANOVA F(4,45) = 11.048, P < .001). Normalization of CL response for 1000 PMNs revealed that FLZ dose-dependently albeit insignificantly reduced the activity of PMNs. The high dose of FLZ caused 2.29-fold decrement in the area under curve (AUC) pertaining to cumulative CL response. The findings of this study suggest that FLZ protects rats against septic shock by inhibiting PMN-mediated inflammatory cascade without compromising their phagocytic activity.  相似文献   

17.
It has been suggested that oxidative stress plays an important role in the chronic complications of diabetes. The experimental findings regarding the changes in tissue antioxidant enzymes and lipid peroxidation of diabetic tissues have been inconsistent. Previous studies in our laboratory demonstrated that the reducing power of a specific tissue correlates with its low molecular weight antioxidant (LMWA) capacity. In the present study, the overall LMWA capacity (reducing equivalents) of plasma and tissues of streptozotocin (STZ)-induced diabetic rats (1–4 weeks) and insulin treated diabetic rats were measured by cyclic voltammetry. Levels of water and lipid soluble LMWA capacity progressively decreased in the diabetic plasma, kidney, heart and brain, while the diabetic liver, at 2, 3 and 4 weeks after STZ injection, showed a significant increase in the overall lipid soluble LMWA capacity (p < 0.001). Subsequently, analysis of specific components by high pressure liquid chromatography (electrochemical detection) showed decreased levels of ascorbic acid in plasma, kidney, heart and brain of diabetic animals. The α-tocopherol level dropped in all tissues, except for the liver in which there was a significant increase (p < 0.01 and p < 0.001 at 2–4 weeks). Lipid peroxidation was assessed by conjugated diene levels, which increased significantly in all diabetic tissues except the liver. Insulin treatment that was started after 3 weeks of diabetes and continued for 3 weeks showed no change in the conjugated dienes and in the overall LMWA capacity in all organs. Our results suggest a unique behavior of the liver in the STZ-induced diabetic rats to the stress and indicate its higher capacity to cope with oxidative stress as compared to other organs.  相似文献   

18.
Hydrogen peroxide plays a major role in the pathomechanism of diabetes mellitus and its main regulator is enzyme catalase.

The blood catalase and the C111T polymorphism in exon 9 was examined in type 1, type 2 and gestational diabetes mellitus.

Compared to the control group (104.7 ± 18.5 MU/l) significantly decreased (p < 0.001) blood catalase activities were detected in type 2 (71.2 ± 14.6 MU/l), gestational (68.5 ± 12.2 MU/l) diabetes mellitus and without change in type 1 (102.5 ± 26.9 MU/l). The blood catalase decreased (p = 0.043) with age for type 2 diabetics and did not change (p>0.063) for type 1, gestational diabetic patients and controls. Blood catalase showed a weak association with hemoglobin A1c for type 1 diabetic patients (r = 0.181, increasing).

The mutant T allele was increased in type 1 and gestational diabetes mellitus, and CT+TT genotypes showed decreased blood catalase activity for type 1 and increased activities for type 2 diabetic patients.

The C111T polymorphism may implicate a very weak effect on blood catalase activity in different types of diabetes mellitus.  相似文献   

19.
The evolutionary conserved family of heat shock proteins (HSP) is responsible for protecting cells against different types of stress, including oxidative stress. Although the levels of HSPs can be readily measured in blood serum, the levels of HSP70 in patients with different durations of diabetes have not been studied before. We quantified serum HSP70 levels in a healthy control group (n = 36) and two groups of type 2 diabetic patients, defined as newly diagnosed diabetes (n = 36) and patients with diabetes duration of more than 5 years (n = 37). The clinical characteristics and biochemical parameters were evaluated in the studied population. We found that serum HSP70 levels were significantly higher in patients with diabetes when compared with controls (p < 0.001) and it was higher in patients with disease for more than 5 years than in newly diagnosed patients (p < 0.001). Serum HSP70 was inversely correlated with fasting blood sugar in patients with diabetes for more than 5 years (r = −0.500, p = 0.002), positively correlated with the history of hypertension in newly diagnosed patients (p < 0.001), and positively correlated with age in patients with diabetes (r = 0.531, p = 0.001). Serum level of HSP70 is significantly higher in patients with diabetes and correlates with the duration of disease. Higher HSP70 in prolonged diabetes versus newly diagnosed diabetes may be an indicator of metabolic derangement in the course of diabetes.  相似文献   

20.
Comparisons of phagocytic parameters were carried out by a recently developed fluorescence test which is reproducible, simple and fast. Phagocytosis by polymorphonuclear leucocytes (PMNs) obtained from patients with psoriasis was compared with that of healthy individuals. Psoriatic skin scales, non-sterile and sterile, were tested for stimulatory effect on PMNs and compared with the effect of normal skin scrapings. Results confirm enhanced phagocytosis of bacteria by PMNs from patients with psoriasis over that of PMNs from healthy volunteers. Furthermore, the supernatant fluid from suspensions of psoriatic skin scales, non-sterile and sterile, stimulated PMNs activity.  相似文献   

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