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91.
Our research focused on the preparation of vesicular drug delivery systems, such as liposomes, noisomes, and sphingosomes, for achieving slow release of entrapped proteins in the circulation to increase half-life, to mask immunogenic properties, and to protect against loss of enzymatic activity. We prepared, characterized, and monitored the biodistribution of three types of vesicular systems (liposomes, niosomes, and sphingosomes) containing streptokinase. For biodistribution stuides, radiolabelled streptokinase dispersions were injected into the ear vein of female rabbits in the weight of 2.5-3 kg weight. Following the application, rabbits were sacrificed, then organs of these animals were removed and radioactivity of organs was measured by well-type gamma counter. The comparison of the biodistribution results of the free streptokinase with the streptokinase vesicles showed that incorporation of the enzyme into the vesicles changed the biodistribution of the drug and by the entrapment of the streptokinase in the vesicles, thrombus uptake and imaging quality were improved. 相似文献
92.
Doxorubicin (DXR) is an anthracycline antibiotic, broadly used in tumor therapy. In the present study we investigated whether vitamin E and catechin can reduce the toxic effects of doxorubicin. Vitamin E (200 IU/kg/week), catechin (200 mg/kg/week), doxorubicin (5 mg/kg/week), doxorubicin+vitamin E (200 IU/kg/week), doxorubicin+catechin (200 mg/kg/week) combinations were given to rats weighing 210-230 g (n=6/group). Changes in major enzymes participating in free radical metabolism superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase (GSHPx), catalase (CAT) and malondialdehyde (MDA) were evaluated in the livers of all animals. Superoxide dismutase and catalase activity increased in the doxorubicin-treated group compared to control (P<0.05). Glutathione peroxidase levels increased in the catechin+doxorubicin-treated group (P<0.05) and reached maximum concentrations in the doxorubicin-treated group compared to control (P<0.01). Malondialdehyde levels increased in the doxorubicin-treated group compared to control and all-treated groups (P<0.05). Malondialdehyde, glutathione peroxidase and catalase activities were decreased in the vitamin E+doxorubicin- and catechin+doxorubicin-treated group compared to doxorubicin-treated group (P<0.05). All enzymes activities showed no statistical differences in the not mentioned groups above (P>0.05). Electron microscopic studies supported biochemical findings. We conclude that vitamin E and catechin significantly reduce doxorubicin-induced hepatotoxicity in rats. 相似文献
93.
Aydemir O Aydemir C Sarikabadayi YU Altug N Erdeve O Uras N Oguz SS Dilmen U 《Early human development》2012,88(5):315-319
Background/Aim
Transient tachypnea of the newborn (TTN) is a consequence of inadequate neonatal lung fluid clearance. Natriuretic peptides play an important role in the regulation of extracellular fluid volume. The aim of the study was to investigate the relation between plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and TTN, and to find out its role in predicting disease severity.Methods
A prospective controlled study involving 67 infants with TTN and 33 controls ≥ 34 weeks gestational age was conducted. Study and control groups were compared for plasma NT-proBNP levels measured on the 6th, 24th, 72nd and 120th hours of life. Cardiac systolic functions were evaluated by echocardiography.Results
NT-proBNP levels were significantly higher in neonates with TTN compared to controls at 6th, 24th, 72nd and 120th hours (p < 0.001). NT-proBNP levels at 24th and 72nd hours were significantly higher in infants with prolonged tachypnea (p = 0.007 and p = 0.03) and in those who required respiratory support (p = 0.006 and p < 0.001). Tachypnea duration was correlated with NT-proBNP levels at 24 h (r = 0.41, p = 0.001). At a cut-off value of 6575 pg/ml, NT-proBNP had a sensitivity of 85% and specificity of 64% to predict mechanical ventilation requirement. Cardiac systolic functions were normal in all TTN patients.Conclusion
Plasma NT-proBNP levels are increased in neonates with TTN. Measurement of plasma NT-proBNP can be useful for predicting infants who will have prolonged tachypnea and mechanical ventilation requirement. 相似文献94.
95.
Koc E Reis KA Ebinc FA Pasaoglu H Demirtas C Omeroglu S Derici UB Guz G Erten Y Bali M Arinsoy T Sindel S 《Clinical and experimental nephrology》2011,15(5):658-665
Background
It has been shown that beta-glucan (BG), which has antioxidant and immunomodulatory effects, attenuats renal ischemia–reperfusion injury. We aimed to investigate whether BG might have a preventive role against the development of contrast-induced nephropathy and to compare its effect with nebivolol (Nb) and N-acetylcysteine (NAC).Methods
Thirty-six Wistar albino female rats were randomly divided into six groups (n?=?6 each): control, contrast media (CM), BG, BG?+?CM, Nb?+?CM, and NAC?+?CM. With the exception of control and CM groups, the others were given drugs orally once a day for 5?days. Kidney function parameters, inflammatory parameters, and serum and renal tissue oxidative stress markers were measured.Results
Increases of serum creatinine and blood urea nitrogen levels were significantly higher (p?0.05) in the CM group only. Absolute changes of serum creatinine levels in BG, BG?+?CM and Nb?+?CM groups were significantly lower than those in the CM group (p?0.05). Serum levels of advanced oxidation protein products and malondialdehyde were significantly less (p?0.05) in the BG group compared to the CM group. Histopathological lesions in the CM group were more advanced (p?0.05). No significant differences between the BG?+?CM, Nb?+?CM and NAC?+?CM groups were found with regard to histopathological findings.Conclusion
This study suggests that BG protects or ameliorates against contrast-induced nephropathy. Its beneficial effects may be similar to or greater than those of Nb or NAC. 相似文献96.
Grandesso F Hagerman A Kamara S Lam E Checchi F Balkan S Scollo G Durand R Guthmann JP 《Tropical medicine & international health : TM & IH》2006,11(7):1017-1021
OBJECTIVE: In 2004, Sierra Leone adopted artesunate plus amodiaquine as first-line antimalarial treatment. We evaluated the efficacy of this combination in Kailahun, where a previous study had shown 70.2% efficacy of amodiaquine in monotherapy. METHODS: Method and outcome classification of the study complied with WHO guidelines. Children 6-59 months with uncomplicated malaria were followed-up for 28 days. PCR genotyping was used to distinguish recrudescence from reinfection. Reinfections were reclassified as cured. RESULTS: Of 172 children who were referred to the study clinic, 126 satisfied inclusion criteria and were enrolled. No early treatment failures were reported. The day 14, efficacy was 98.2% (95% CI: 93.8-99.8). Of 65 recurrent parasitaemias analysed by PCR, 17 were recrudescences. The PCR-adjusted day 28 efficacy was 84.5% (95% CI: 76.4-90.7). All true failures occurred in the last 8 days of follow-up. Of 110 children who completed the 28-day follow-up, 54 (49.1%) experienced a novel infection. CONCLUSION: The efficacy of this combination was disappointing. The high reinfection rate suggested little prophylactic effect. In Kailahun a more efficacious combination might be necessary in the future. The efficacy of AS + AQ needs to be monitored in Kailahun and in the other regions of Sierra Leone. 相似文献
97.
98.
Miura Y Naito M Ablake M Terayama H Yi SQ Qu N Cheng LX Suna S Jitsunari F Itoh M 《Asian journal of andrology》2007,9(2):199-205
Aim: To determine the biochemical effect of di-(2-ethylhexyl) phthalate (DEHP) on testes, liver, kidneys and pancreas on day 10 in the process of degeneration of the seminiferous epithelium. Methods: Diets containing 2% DEHP were given to male Crlj:CDI(ICR) mice for 10 days. The dose of DEHP was 0.90±0.52 mg/mouse/day. Their testes, livers, kidneys and pancreata were examined for detection of mono-(2-ethylhexyl) phthalate (MEHP), nitrogen oxides (NOx) produced by peroxidation of nitric oxide (NO) with free radicals, and lipid peroxidation induced by the chain reaction of free radicals. Results: Histological observation and serum analysis showed the presence of severe sperrnatogenic disturbance, Leydig cell dysfunction, liver dysfunction and dehydration. Unexpectedly, the concentration of MEHP in the testes was extremely low compared with that in the liver. However, the concentration of the NOx in the testes was as high as the hepatic concentration. Furthermore, free radical-induced lipid peroxidation was histochemically detected in the testes but not in the liver. Conclusion: The results indicate that DEHP-induced aspermatogenesis is caused by the high sensitivity of the testicular tissues to MEHP rather than the specific accumulation or uptake of circulating MEHP into the testes. 相似文献
99.
To investigate the preventive effects of d-psicose, one of rare ketohexoses, on di-(2-ethylhexyl) phthalate (DEHP)-induced testicular injury, prepubertal male Sprague-Dawley rats were exposed to DEHP via their diet or orally, while under treatment with d-psicose. The rats given a diet-containing 1% DEHP alone for 7-14 days showed severe testicular atrophy accompanied by aspermatogenesis. On the other hand, those given the diet plus 2% but not 1% d-psicose-supplemented water for 14 days did not develop testicular atrophy, and exhibited an almost complete spermatogenesis. There was no significant difference in plasma mono-(2-ethylhexyl) phthalate (MEHP) levels between the d-psicose-free and d-psicose-treated groups. The testicular malondialdehyde (MDA) level after a single oral administration of 2g/kg of DEHP showed a similar pattern of increase to the plasma MEHP level and peaked in 24h suggesting a close and dose-dependent relation between plasma MEHP and testicular reactive oxygen species (ROS) levels. Pretreatment with d-psicose at a concentration of 2% and 4% resulted in an almost complete but not absolute suppression of testicular MDA production among rats administered 2g/kg of DEHP. The microarray analysis showed the induction of oxidative stress related genes including the thioredoxin, glutathione peroxidase 1 and 2, glutaredoixn 1 after 24h of the DEHP treatment in the testis. These results show that d-psicose prevents DEHP-induced testicular injury by suppressing the generation of ROS in the rat testis. This effect may be due to the direct scavenging by d-psicose of ROS generated in the testis. 相似文献
100.
Psoriasis is a proliferative and inflammatory disease of the skin. Caspase 9 is responsible for initiating the caspase activation cascade during apoptosis. Apoptosis is a physiological mechanism of homeostasis and development, and caspases are the executioners of apoptosis. This study reports the immunohistochemical localisation of caspase 9 in psoriatic skin and compares it with that seen in normal, healthy control skin. Skin biopsy specimens of lesions were obtained from 15 patients with plaque type psoriasis vulgaris. The specimens were labelled immunohistochemically for binding of an anti-caspase 9 primary antibody. Biopsies of healthy skin from 10 age-matched and sex-matched healthy control individuals were also analysed. The caspase 9 positive cell fraction was calculated for both epidermal and dermal cells in psoriatic lesions and healthy control skin. Counts of caspase 9 positive cells from the epidermis of psoriatic skin lesions were significantly lower than those seen in healthy skin (p<0.05). The caspase 9 immunolabelled perivascular cell counts in the dermis were not statistically significantly different in psoriatic lesions versus normal skin (p>0.05). Psoriatic epidermis contains little of the apoptotic marker, caspase 9. The results of this study are indicative of decreased apoptosis in psoriatic epidermis, and no change in the perivascular area in psoriatic lesions. These findings support the idea that decreased apoptosis is seen in psoriatic epidermal cells. Greater understanding of the nature of the disease may open new avenues for further therapeutic modalities. 相似文献