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941.
Marco Duering Sofia Finsterwalder Ebru Baykara Anil Man Tuladhar Benno Gesierich Marek J. Konieczny Rainer Malik Nicolai Franzmeier Michael Ewers Eric Jouvent Geert Jan Biessels Reinhold Schmidt Frank-Erik de Leeuw Ofer Pasternak Martin Dichgans 《Alzheimer's & dementia》2018,14(6):764-774
Introduction
Diffusion tensor imaging detects early tissue alterations in Alzheimer's disease and cerebral small vessel disease (SVD). However, the origin of diffusion alterations in SVD is largely unknown.Methods
To gain further insight, we applied free water (FW) imaging to patients with genetically defined SVD (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy [CADASIL], n = 57), sporadic SVD (n = 444), and healthy controls (n = 28). We modeled freely diffusing water in the extracellular space (FW) and measures reflecting fiber structure (tissue compartment). We tested associations between these measures and clinical status (processing speed and disability).Results
Diffusion alterations in SVD were mostly driven by increased FW and less by tissue compartment alterations. Among imaging markers, FW showed the strongest association with clinical status (R2 up to 34%, P < .0001). Findings were consistent across patients with CADASIL and sporadic SVD.Discussion
Diffusion alterations and clinical status in SVD are largely determined by extracellular fluid increase rather than alterations of white matter fiber organization. 相似文献942.
943.
Kanbay M Ozkara A Selcoki Y Isik B Turgut F Bavbek N Uz E Akcay A Yigitoglu R Covic A 《International urology and nephrology》2007,39(4):1227-1233
Background Hyperuricemia has been associated with the development of hypertension, cardiovascular, and renal disease. However, there
is no data about the effect of lowering uric acid level on hypertension, renal function, and proteinuria in patients with
glomerular filtration rate (GFR) >60 ml/min. We therefore conducted a prospective study to investigate the benefits of allopurinol
treatment in hyperuricemic patients with normal renal function.
Materials and methods Forty-eight hyperuricemic and 21 normouricemic patients were included in the study. Hyperuricemic patients received 300 mg/day
allopurinol for three months. All patients’ serum creatinine level, 24-h urine protein level, glomerular filtration rate,
and blood pressure levels were measured at baseline and after three months of treatment.
Results A total of 59 patients completed the three-month follow-up period of observation. In the allopurinol group, serum uric acid
levels, GFR, systolic and diastolic blood pressure, and C-reactive protein (CRP) levels significantly improved (P < 0.05). However, urine protein excretion remained unchanged (P > 0.05). No correlation was observed between changes in GFR and changes in CRP, or blood pressure in the allopurinol group.
No significant changes were observed in the control group (P > 0.05).
Conclusion We bring indirect evidence that hyperuricemia increases blood pressure, and decreases GFR. Hence, management of hyperuricemia
may prevent the progression of renal disease, even in patients with normal renal function, suggesting that early treatment
with allopurinol should be an important part of the management of chronic kidney disease (CKD) patients. Long-term follow-up
studies are warranted to identify the benefits of uric acid management on renal function and hypertension. 相似文献
944.
Choroidal vascularity index as an indicator of vascular status of choroid,in eyes with nanophthalmos
Funda Ebru Aksoy Cigdem Altan Cem Kesim Ali Demircan Ugur Tun Gokhan Demir Muhittin Taskapl 《Eye (London, England)》2020,34(12):2336
PurposeTo investigate choroidal vascular index (CVI) in eyes with nanophthalmos (NO) with the use of optical coherence tomography (OCT).MethodsMacular enhanced depth imaging OCT scans of 25 eyes of 25 patients with NO and age–gender-matched 25 eyes of 25 control subjects were analysed. Images were binarized using the ImageJ software, and total choroid area (TCA), luminal area (LA) and stromal area (SA) were acquired. The main outcome measure was CVI, defined as the ratio of LA to TCA.ResultsTwenty-five eyes of 25 patients with NO and age–gender-matched control subjects were enrolled. The mean TCA, SA and LA were found to be significantly higher in patients with NO (2.51 ± 0.44 vs. 1.91 ± 0.35 mm2, P < 0.001; 0.86 ± 0.17 vs. 0.63 ± 0.13 mm2, P < 0.001; and 1.65 ± 0.29 vs. 1.27 ± 0.23 mm2, P < 0.000, respectively). On the contrary, CVI did not significantly differ between the two groups (65.72, 67.68, P = 0.099).ConclusionAs a novel OCT-based marker, CVI could be used to assess vascular status of the choroid in eyes with NO and can provide better understanding of the pathogenesis of this disease.Subject terms: Eye abnormalities, Scleral diseases, Predictive markers, Hereditary eye disease, Uveal diseases 相似文献
945.
Cengiz Sarikurkcu Kadir Arisoy Bektas Tepe Ahmet Cakir Gulsah Abali Ebru Mete 《Food and chemical toxicology》2009,47(10):1017-2483
This study is designed to examine the chemical composition and antioxidant activity of the essential oil and different solvent extracts of Vitex agnus castus. GC and GC–MS analysis was resulted in the detection of 27 components, representing 94.5% of the oil. Major components of the oil were 1,8-cineole (24.98%), sabinene (13.45%), α-pinene (10.60%), α-terpinyl acetate (6.66%), and (Z)-β-farnesene (5.40%). Antioxidant activities of the samples were determined by three different test systems, DPPH, β-carotene/linoleic acid and reducing power assays. In all systems, water extract exhibited excellent activity potential than those of other extracts (hexane, dichloromethane, ethyl acetate and methanol) and the oil. As expected, amount of total phenolics was very high in this extract (112.46 ± 1.22 μg GAEs/mg extract). Dichloromethane extract has been found to be rich in flavonoids. A positive correlation was observed between the antioxidant activity potential and total phenolic and flavonoid levels of the extracts. 相似文献
946.
947.
Coloboma is one of the congenital ocular malformations presenting important diagnostic and therapeutic problems, especially in infants. Coloboma can be associated with microphthalmia frequently and macrophtalmia rarely. However, the association of coloboma, macrophthalmia, and orbital cyst was not reported previously in the literature. A case of coloboma associated with macrophtalmia and cyst was presented, and MR findings of this anomaly was defined with emphasis to the importance of radiologic examinations in the diagnosis of some congenital ocular malformations. 相似文献
948.
Ebru Kilicay Zeynep Karahaliloglu Pınar Alpaslan Baki Hazer 《Journal of biomaterials science. Polymer edition》2017,28(15):1762-1785
Antisense oligonucleotide (ASO)-conjugated-α-tocopherol succinate (TCS)-loaded-poly(lactic acid)-g-poly(ethylene glycol) nanoparticles (ASO-TCS-PLA-PEG NPs), with the ratio of polymer/TCS of 10:2.5, 10:5, 10:7 (w/w) were prepared for targeting cancer therapy. The amphiphilic PLA, amino terminated PEG graft copolymers were synthesized by ring opening polymerization reaction. Nanoparticles were produced by using double emulsion (w/o/w) solvent evaporation method. ASO-TCS-PLA-PEG NPs demonstrated satisfactory encapsulation and loading efficiency and size distribution. The short-term stability studies were carried out at 4 and 25 °C for 30 days to assess their mean particle size, polydispersity index and zeta potential. The cellular uptake and extended cytoplasmic retention of the NPs in A549 human lung carcinoma and L929 mouse fibroblast cells were examined by fluorescence and confocal microscopy. In human lung cancer cells, ASO-TCS-PLA-PEG NPs exhibited better cellular internalization, cytotoxicity and apoptotic and necrotic effects compared to healthy cell line, L929. These findings showed that ASO-modified nanoparticles could serve as a promising nanocarrier for targeted tumor cells. 相似文献
949.
Guler G Balci S Costinean S Ussakli CH Irkkan C Suren D Sari E Altundag K Ozisik Y Jones S Bacher J Shapiro CL Huebner K 《Modern pathology》2012,25(7):949-955
It has been reported previously that: (1) normal-breast epithelial cells that are CD24-/44+ express higher levels of stem/progenitor cell-associated genes; (2) cancer cells that have undergone epithelial to mesenchymal transition display CD24-/44+ cell-surface expression, a marker for breast cancer stem cells; (3) loss of E-cadherin is a preliminary step in epithelial to mesenchymal transition; and (4) vimentin is a marker of mesenchymal phenotype. We hypothesized that stem cell subpopulations would be more frequent in metastatic than in primary tumors. Therefore we assessed by immunohistochemical analysis, tissue microarrays containing tissue from primary and associated metastatic breast cancers for expression of CD24, CD44, E-cadherin and vimentin to evaluate candidate cancer-initiating cell populations in breast cancer subtypes and metastatic lesions. The occurrence of CD24-/44+ and CD24+/44- cells did not differ in primary vs matched lymph node or distant and locoregional metastatic lesions; E-cadherin expression was decreased in primary vs lymph node metastases (P=0.018) but not decreased in distant and locoregional metastases relative to primary tumor, whereas vimentin, was more frequently expressed in lymph node and distant and locoregional metastases (P=0.013, P=0.004) than in matched primary cancers. Thus, the frequency of CD24-/44+ cells does not differ in metastases relative to the primary breast cancer but differs by tumor stage and subtype. 相似文献
950.