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951.
Matrix type transdermal films of donepezil (DNP) as an alternative delivery approach was designed to improve patient compliance to Alzheimer disease treatment. Sodium alginate, a natural polysaccharide, was used as matrix-forming agent in the optimization of transdermal films. Propylene glycol and dl-limonene was added into films as a plasticizer and permeation enhancer, respectively. As well as mechanical strength and bioadhesiveness of optimized transdermal films of DNP, the impact of dl-limonene concentration in films on DNP in vitro permeation across pig skin was assessed. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) measurements were carried out to examine the effects of enhancer on in vitro conformational order of the stratum corneum intercellular lipids following permeation study. Results showed that transdermal formulations of DNP were suitable due to both mechanical and bioadhesive features of the films. In vitro skin permeation study indicated that dl-limonene at a concentration of 3% was optimum with high drug flux. ATR-FTIR results confirmed a more fluidized stratum corneum lipid state in the presence of dl-limonene, indicating its permeation enhancement effect. Regarding to achieve therapeutic levels of DNP, it seems to be feasible deliver DNP with transdermal films for the management of Alzheimer disease.KEY WORDS: Alzheimer disease, donepezil, limonene, permeation enhancement, transdermal film 相似文献
952.
Akın Sibel Özer Firüzan Fırat Zararsız Gözde Ertürk Şafak Elif Deniz Mucuk Salime Arguvanlı Sibel Mazıcıoğlu Mümtaz 《Sleep and biological rhythms》2020,18(3):243-248
Sleep and Biological Rhythms - The aim of this study was to examine the association between sleep duration and frailty in community-dwelling Turkish older adults and to determine whether this... 相似文献
953.
Böyük A Banlı O Gümüş M Evliyaoğlu O Demirelli S 《Biological trace element research》2011,143(3):1282-1288
Laparoscopic adjustable gastric banding (LAGB) causes significant weight loss in morbidly obese adults. However, its consequences
on nutritional status still remain unclear. There are a few studies determining the nutritional status after LAGB and none
have focused on the serum levels of zinc (Zn), copper (Cu), and ceruloplasmin (CP). We aimed to investigate the effects of
LAGB surgery on plasma Zn, Cu, and CP levels. Thirty patients with LAGB with morbid obesity were included. Blood samples were
collected preooperatively and in the postoperative third month to determine plasma Zn, Cu, and CP levels. The mean preoperative
and postoperative body mass indexes (BMI) were 44.9 ± 7.4 kg/m2 and 44.1 ± 6.5 kg/m2, respectively. The mean weight loss was 12.9 ± 3.3 kg at the postoperative third month. The postoperative Zn (500 ± 130 ng/ml),
Cu (280 ± 80 ng/ml), and CP (23.9 ± 8.8 mg/dl) values were statistically significantly lower than the preooperative Zn (740 ± 230 ng/ml),
Cu (370 ± 80 ng/ml) and CP (33.3 ± 15.7 mg/dl) levels (p < 0.05). Decreases in the plasma levels of Zn, Cu, and CP were seen postoperatively following LAGB surgery. The nutritional
status of LAGB-applied patients should be monitored and mineral supplementation may be considered. 相似文献
954.
Özkaya D Naziroğlu M Armağan A Demirel A Köroglu BK Çolakoğlu N Kükner A Sönmez TT 《Cell biochemistry and function》2011,29(4):287-293
Diabetes induces oxidative stress in aged human and rat, although daily supplementation of vitamins C and E (VCE) can be beneficial to aged diabetic rats by reducing free radical production. The aim of the present study was to evaluate whether dietary VCE supplementation relieves oxidative stress in streptozotocin (STZ)-induced diabetic in aged rats. Thirty aged rats were randomly divided into three groups. The first group was used as a control. The second group was made diabetic using a single dose of intraperitoneal STZ. VCE-supplemented feed was given to aged diabetic rats constituting the third group. On the 21st day of the experiment, blood, lens and kidney samples were taken from all animals. Glutathione peroxidase (GSH-Px) activity in lens and kidney, reduced glutathione (GSH), vitamin E and β-carotene concentrations in kidney were lower in the diabetic group than in the control whereas plasma glucose, urea and creatinine, and kidney and lens peroxidation (LP) levels were higher in the diabetic group than in the control. However, kidney and lens LP levels, and plasma glucose, urea and creatinine values were decreased by VCE supplementation. Lens and kidney GSH-Px activity, kidney GSH, vitamin E and β-carotene concentrations and erythrocyte counts were increased by VCE treatment. Kidney weights, vitamin A, haemoglobin, hematocrit, leukocyte and platelets values were not changed by diabetes and/or VCE supplementation. VCE ameliorated also diabetes-induced histopathological changes in kidney. In conclusion, we observed that VCE supplementation is beneficial towards kidney and lens of aged diabetic rats by modulating oxidative and antioxidant systems. 相似文献
955.
Banu?BayramEmail author Emrah?Say?n Hasan?Veysi?Güne? ?rfan?De?irmenci Züleyha?Türko?lu Fulya?Doganer Didem?Turgut?Co?an 《Molecular biology reports》2011,38(3):1713-1716
This study was conducted in Turkish osteoarthritis patients to determine the frequency of I/D polymorphism genotypes of angiotensin
converting enzyme gene, and to examine the role of this polymorphism in osteoarthritis development. Genomic DNA obtained from
200 persons (135 patients with osteoarthritis and 65 healthy controls) was used in the study. DNA was multiplied by polymerase
chain reaction using I and D allele-specific primers. Polymerase chain reaction products were assessed with CCD camera by
being exposed to 2% agarose gel electrophoresis. There was statistically significant difference between the groups with respect
to genotype distribution (P < 0.001). The D allele frequency was indicated as 69% and I allele was as 31% in the patients, whereas it was 55–45% in the
control group. Consequently, in this study, we may assert that ACE gene I/D polymorphism DD genotype determination is significant
criteria for identifying patients who are likely to develop osteoarthritis in east population of Turkey. 相似文献
956.
This experiment was conducted to evaluate the effects of L-carnitine on performance, egg quality and certain biochemical parameters in laying hens fed a diet containing high levels of copper proteinate. Forty-eight 42-week-old laying hens were divided into four groups with four replicates. The laying hens were fed with a basal diet (control) or the basal diet supplemented with either 400 mg carnitine (Car)/kg diet, 800 mg copper proteinate (CuP)/kg diet or 400 mg carnitine + 800 mg copper (Car+CuP)/kg diet, for 6 weeks. Supplemental CuP decreased feed consumption (p?0.01), feed efficiency and egg production (p?0.001), as compared to control. The combination of Car and CuP increased (p?0.001) egg production and feed efficiency as compared to CuP. The activities of alanine aminotransferase (p?0.05) and alkaline phosphatase (p?0.01) were increased, while lactate dehydrogenase activity was decreased (p?0.001) by supplemental CuP and Car+CuP. Supplemental CuP caused an increase in plasma malondialdehyde (p?0.01) and nitric oxide levels (p?0.05). In the Car+CuP group, this increase was observed to have been reduced significantly (p?0.05). Furthermore, Car+CuP increased (p?0.05) glucose level. These results indicate that the carnitine and copper combination may prevent the possible adverse effects of high dietary copper on performance and lipid peroxidation in hens. 相似文献
957.
Müezzinoğlu T Korkmaz M Neşe N Bakırdere S Arslan Y Ataman OY Lekili M 《Biological trace element research》2011,144(1-3):49-57
We investigated the possible relationship between boron exposure and prostate cancer (PCa) for men living and being employed at boron mines in villages with rich boron minerals. Out of 456 men studied, 159 were from villages with rich boron sources and boron levels in drinking water of >1?mg?L(-1) and these men formed the study group, while 63 from villages with rich boron sources and boron levels in drinking water of <1?mg?L(-1) were enrolled into control group?1. A further 234 subjects from other villages with no boron mines were considered as control group?2. Prostate specific antigen (PSA) levels could be obtained from a total of 423 men. Urinary boron concentration as an indicator of boron exposure in 63 subjects, prostatic volumes by transrectal ultrasonography in 39 subjects, and prostatic biopsies in 36 subjects were obtained for study and control groups. The daily boron exposure was calculated according to urinary boron levels. Although there was no significant difference among the groups in terms of total PSA levels, the number of subjects with tPSA ≥2.5 and tPSA ≥10.0?ng?dL(-1) prostatic volumes in men whose prostates were biopsied (p?0.012) was significantly lower in the study group as compared with those in the control group?2. These results suggested that high exposure to boron might have an implication within the prostatic cellular processes related to hyperplasia and carcinogenesis, even though we did not find a statistically significant association between PCa and boron exposure. 相似文献
958.
Gümüş M Yüksel H Evliyaoğlu O Kapan M Böyük A Önder A Aldemir M 《Biological trace element research》2011,143(1):386-393
Ellagic acid (EA) is a natural polyphenolic compound. Although, modulator effects of EA on copper (Cu) and zinc (Zn) levels
in some liver diseases have been reported in experimental animals, its effects in obstructive jaundice (OJ) has not been clarified.
We aimed to evaluate potential effects of EA on Cu and Zn levels in liver and serum of cholestatic rats. Forty Wistar albino
rats were equally divided into four groups. First group was used as controls. Second group received EA (60 mg−1 kg−1 day−1) for 8 days. Third was OJ group, and fourth group was OJ plus EA group. After 8 days, blood and liver samples were obtained.
Higher serum and liver Cu and lower serum and liver Zn levels were found in OJ group (p < 0.05) compared with other groups. However, these differences reached to significant levels for Cu in serum and for Zn in
lever. Higher serum copper levels were decreased, and lower liver Zn levels were increased by EA treatment in cholestatic
rats (p < 0.05). Also, higher Cu/Zn ratio in OJ group was decreased by EA treatment both in liver (p < 0.05) and in serum (p < 0.05). Significantly higher serum bilirubin, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase
values were found in OJ and OJ + EA groups compared with the control and EA groups (p < 0.05). In conclusion, result of the current study indicated that ellagic acid has modulator effects on Cu and Zn levels
in liver and serum of cholestatic rats. 相似文献
959.
Aside from its excellent mechanical properties, spider silk (SS) would offer an active surface for heavy metal interaction due to its rich protein structure. The present study describes the potential use of natural (SS) as a sorbent of heavy metals from aqueous solutions. Single and multi-species biosorption experiments of heavy metals by natural SS were conducted using batch and column experiments. The biosorption kinetics, in general, was found to follow the second-order rate expression, and the experimental equilibrium biosorption data fitted reasonably well to Freundlich isotherm. From the Freundlich isotherm, the biosorption capacities of Cu(II) and Pb(II) ions onto SS were found as 0.20 and 0.007 mmol g?1, respectively. The results showed a decrease in the extent of metal ion uptake with lowering the pH. 相似文献
960.
Tonguç E Ceylaner G Var T Zülfkaroğlu E Ceylaner S 《Genetic counseling (Geneva, Switzerland)》2011,22(2):193-198
Gonadotropins are widely accepted agents for ovulation induction in infertile women. On the other hand, several authors discuss the possible effect of gonadotropins on the developmental mechanism of ovarian cancer. SCE is a method of genotoxicity investigation and it is an excellent parameter to monitor the DNA damage and repair. There are numbers of studies showing the relationship between endogenous or exogenous hormones and SCEs. The aim of this study was to investigate with SCE techniques the effects of long-term (6 months) use of gonadotropins on DNA as we couldn't find any other study on the effect of long term use. We found increased sister chromatid exchange rates in a study group as compared to a control group. This may be one of the causes of increased ovarian cancer risk in infertile population. 相似文献