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1.
Elevated NMDA receptors in parkinsonian striatum. 总被引:3,自引:0,他引:3
Dopamine-glutamate interactions contribute to normal striatal function and have been implicated in neurotoxicity at nigrostriatal dopamine (DA) terminals. The present study examined the striata of idiopathic Parkinson's disease (PD) patients and age-matched controls for regional differences in the DA transporter and binding to N-methyl-D-aspartate (NMDA) receptors. [3H]Mazindol labeling of the DA transporter was reduced by 70-80% in the caudate and putamen of PD patients, with reductions being more extensive dorsally than ventrally. In contrast, L-[3H]glutamate binding to NDMA-sensitive receptors was 20-40% higher in PD cases than in controls. These findings raise the possibility that modifications occur within corticostriatal glutamate synapses of PD patients, possibly as a consequence of reduced nigrostriatal DA activity. 相似文献
2.
The effect of intramuscular administration of a mixture of gangliosides (21% GM1, 39.7% GD1a,, 16% GD1b, 19% GT1 in a daily dose of 50 mg per kg upon the time course of changes in hippocampal acetylcholinesterase and choline acetyltransferase activities after extensive medioventral septal lesions in the rat was checked on days 3, 5, 18 and 50 after the operation. Following the early decrease in the enzyme activities to about 25% of control due to degeneration, a gradual recovery up to about 50% of control activity at the 50th day was found. When gangliosides were administered, the recovery in the activity of both enzymes was more pronounced. The ratio of the enzyme activities from the animals injected with gangliosides to that from uninjected animals was 1.45 and 1.48 on the 18th day and 1.62 and 1.50 on the 50th day after the operation, for choline acetyltransferase and acetylcholinesterase activity, respectively. Since no significant effect of ganglioside injection was seen at early postoperative times i.e. on days 3 and 5, the effects seen on days 18 and 50 seem to be specifically due to facilitation of the recovery processes and not to retardation of the degeneration processes.Assuming that the spontaneous recovery of cholinergic enzyme activity reflects reinnervation of the hippocampus through collateral sprouting, gangliosides would seem to facilitate the regrowth of new cholinergic nerve terminals. 相似文献
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4.
Halis Boran Erol Capkin Ilhan Altinok Ertugrul Terzi 《Experimental and toxicologic pathology》2012,64(3):175-179
Acute toxicity of the fungicide, captan, to juvenile rainbow trout was evaluated under static-renewal test condition. Actual concentrations of captan ranged from 0.05 to 1.00 mg/L. The concentrations of captan that killed 50% of the rainbow trout (3.11 ± 0.8 g) within 24 (24 h; LC50), 48, 72 and 96 h were 0.57 ± 0.09, 0.49 ± 0.10, 0.44 ± 0.11 and 0.38 ± 0.13 mg/L (95% confidence limits), respectively. None of the unexposed control fish died and the first fish died 6 h after exposure to captan (≥0.65 mg/L). Hypertrophy, separation of epithelium from lamellae, lamellar fusion, and epithelial cell necrosis were observed on captan exposed fish. Gills also had scattered areas of focal lamellar hyperplasia. Fish exposed to fungicide had inflammation and necrosis in liver, trunk kidney and spleen. In order, the most affected organs were gill, trunk kidney and liver. 相似文献
5.
Ali Akal Turgay Ulas Tugba Goncu Muhammet Emin Guldur Sezen Kocarslan Abdullah Taskin 《Cutaneous and ocular toxicology》2015,34(2):139-143
Objective: In this experimental study, we investigated the possible effects of intracameral moxifloxacin on oxidative stress parameters and endothelial cell morphology in corneal tissue.Methods: In total, 30 rats were randomly assigned to three groups of 10 rats: the sham group (Group 1, n?=?10); the control group (Group 2), where balanced salt solution (BSS) was administered at a dose of 0.01?cc (n?=?10); and the treatment group (Group 3), where moxifloxacin was administered at a dose of 0.05?mg/0.01?cc (n?=?10). Total antioxidant status (TAS) and total oxidant status (TOS) in corneal tissue and blood samples were measured and the oxidative stress index (OSI) was calculated. Also, corneal tissue histopathology was evaluated with caspase-3 and caspase-8 staining. Apoptotic activity was also evaluated.Results: In blood samples, TAS, TOS, and OSI levels were not statistically significantly different (all p?>?0.05). Compared with the sham and control groups, TOS and OSI levels in cornea tissue were significantly different in the moxifloxacin group (all p?0.05). However, compared with the control group, no statistically significant difference was found in the sham group (all p?>?0.05). Compared with the sham and control groups, apoptotic activity was higher in the moxifloxacin group, in both immunohistochemical staining for caspase-3 and caspase-8.Conclusions: Intracameral moxifloxacin injection seems to be safe systemically, but it may have toxic effects on corneal tissues, as suggested by oxidative stress parameters and a histopathological evaluation. 相似文献
6.
Halis Kaan Akturk Ana Maria Chindris Jolaine M. Hines Ravinder J. Singh Victor J. Bernet 《Mayo Clinic proceedings. Mayo Clinic》2018,93(3):284-290
Objective
To assess whether dietary supplements that are herbal and/or animal-derived products, marketed for enhancing metabolism or promoting energy, “adrenal fatigue,” or “adrenal support,” contain thyroid or steroid hormones.Methods
Twelve dietary adrenal support supplements were purchased. Pregnenolone, androstenedione, 17-hydroxyprogesterone, cortisol, cortisone, dehydroepiandrosterone sulfate, synthetic glucocorticoids (betamethasone, dexamethasone, fludrocortisone, megestrol acetate, methylprednisolone, prednisolone, prednisone, budesonide, and triamcinolone acetonide) levels were measured twice in samples in a blinded fashion. This study was conducted between February 1, 2016, and November 1, 2016.Results
Among steroids, pregnenolone was the most common hormone in the samples. Budesonide, 17-hydroxyprogesterone, androstenedione, cortisol, and cortisone were the others in order of prevalence. All the supplements revealed a detectable amount of triiodothyronine (T3) (63-394.9?ng/tablet), 42% contained pregnenolone (66.12-205.2?ng/tablet), 25% contained budesonide (119.5-610 ng/tablet), 17% contained androstenedione (1.27-7.25 ng/tablet), 8% contained 17-OH progesterone (30.09 ng/tablet), 8% contained cortisone (79.66 ng/tablet), and 8% contained cortisol (138.5 ng/tablet). Per label recommended doses daily exposure was up to 1322 ng for T3, 1231.2 ng for pregnenolone, 1276.4 ng for budesonide, 29 ng for androstenedione, 60.18 ng for 17-OH progesterone, 277 ng for cortisol, and 159.32 ng for cortisone.Conclusion
All the supplements studied contained a small amount of thyroid hormone and most contained at least 1 steroid hormone. This is the first study that measured thyroid and steroid hormones in over-the-counter dietary “adrenal support” supplements in the United States. These results may highlight potential risks of hidden ingredients in unregulated supplements. 相似文献7.
Cemri M Timurkaynak T Ozdemir M Boyaci B Yalcin R Cengel A Dörtlemez O Dörtlemez H 《Acta cardiologica》2002,57(2):101-105
OBJECTIVE: It has been claimed that left ventricular (LV) systolic dysfunction impairs left atrial (LA) and left atrial appendage (LAA) functions. In this study, we compared the LA and LAA function parameters in patients with chronic nonvalvular atrial fibrillation (AF) with and without LV systolic dysfunction. METHODS AND RESULTS: The study population consisted of 28 patients with chronic nonvalvularAF. Group I consisted of 12 patients with LV systolic dysfunction (mean age: 61 +/- 14 years; LV ejection fraction: 44 +/- 6%), group II of 16 patients with normal LV systolic function (mean age: 52 +/- 15 years; LV ejection fraction: 65 +/- 3%). LV ejection fraction (EF) was measured by echocardiography utilizing bi-plane area length method.The following LA and LAA transoesophageal echocardiography parameters were obtained: I) LA diameter, 2) LAA ejection velocity, 3) LAA filling velocity, 4) LAA ejection fraction, 5) pulmonary venous (PV) systolic velocity, 6) PV diastolic velocity, 7) PV systolic velocity/diastolic velocity ratio.The left atrium diameter was significantly larger in group I than in group 11 (4.7 +/- 0.7 cm vs. 3.8 +/- 0.6 cm, p < 0.05).The LAA ejection velocity and LAA ejection fraction were significantly lower in group I than in group 11 (22.6 +/- 15.5 cm/s vs 37.5 +/- 11.3 cm/s and 26.9 +/- 20.8% vs. 41.3 +/- 10.9%, p < 0.05 for both comparisons).The PV systolic velocity and PV systolic velocity/diastolic velocity ratio were significantly smaller in group I than in group II (26.2 +/- 14.8 cm/s vs. 51.5 +/- 22 cm/s and 0.7 +/- 0.6 vs. 1.2 +/- 0.5, p < 0.05 for both comparisons).Although decreased LAA filling and PV diastolic velocities were determined in group I, no significant difference existed between groups I and II.Thrombus and/or spontaneous echo contrast (SEC) in the LA and/or LAA were more frequent in group I (75% vs. 18%, p < 0.05). CONCLUSION: These results indicate that LV systolic dysfunction impairs various LA and LA function parameters and is associated with an increased frequency of SEC and/or LA thrombus in patients with chronic nonvalvularAF. 相似文献
8.
Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie - The aim was to study the effects of micro-osteoperforations (MOPs) on miniscrew-supported maxillary molar distalization.... 相似文献
9.
Abdullah Oguz Omer Uslukaya Ulas Alabal?k Ahmet Turkoglu Murat Kapan Zubeyir Bozdag 《International surgery》2015,100(4):656-661
In this study, we aimed to compare the effects of dexpanthenol and N-acetylcysteine on wound healing. The wound healing process is a multifaceted sequence of activities associated with tissue restoration process. A number of investigations and clinical studies have been performed to determine new approaches for the improvement of wound healing. A total of 30 rats were divided into 3 equal groups. A linear 2-cm incision was made in the rats'' skin. No treatment was administered in the first (control) group. Dexpanthenol cream was administered to the rats in the second group and 3% N-acetylcysteine cream was administered to the rats in the third group. The wound areas of all of the rats were measured on certain days. On the 21st day, all wounds were excised and histologically evaluated. The epithelialization and granulation rates between the groups were revealed to be similar in microscopic evaluations. Although the fibrosis was remarkable in the control group as compared with the other groups, it was similar in N-acetylcysteine and dexpanthenol groups. Angiogenesis rate was remarkable in the N-acetylcysteine group compared with the others. In multiple-comparison analysis, Dexpanthenol and N-acetylcysteine groups had similar results in terms of wound healing rates (P < 0.05), which were both higher than in the control group (P > 0.05). The efficacy of N-acetylcysteine in wound healing is comparable to dexpanthenol, and both substances can be used to improve wound healing.Key words: N-acetylcysteine, Dexpanthenol, Wound healingWound healing is a multifaceted sequence of activities associated with the tissue restoration process.1 This activity takes place in 4 main steps: inflammation, proliferation, matrix deposition, and remodeling.2,3 Moreover, there are many factors that might have harmful effects on the wound healing process. In this regard, there have been numerous analyses and clinical studies aiming to find new methods for the improvement of wound healing processes.4Dexpanthenol is the biologically-active alcohol of pantothenic acid, which leads to an elevation in the amount of coenzyme A in the cell. Dexpanthenol is extensively used in topical form, since it can easily penetrate the skin even at large local concentrations. When used in formulations, dexpanthenol is most effective for the stimulation of epithelialization, granulation, and the mitigation of itching.5N-acetylcysteine (NAC) is a prodrug that supplies bioavailable cysteine for glutathione replenishment and prevents oxidative damage as well as inflammation. It also leads to glutathione (GSH) formation in the body. Besides fostering angiogenesis, it is used to scavenge free radicals. NAC has a number of functions in the stages of repair process, including cell proliferation, migration, and scratch wound healing. Moreover, NAC has also been reported to promote wound healing in diabetic rats.6In this study, we aimed to compare the effects of dexpanthenol, a molecule that is widely used to improve wound healing, and NAC, a molecule that reduces oxidative stress and inflammation, on wound healing. 相似文献
10.