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21.
Comert Kural Ahmet Ata Akatay Rapha?l Gaudin Bi-Chang Chen Wesley R. Legant Eric Betzig Tom Kirchhausen 《Molecular biology of the cell》2015,26(11):2044-2053
Clathrin/AP2-coated vesicles are the principal endocytic carriers originating at the plasma membrane. In the experiments reported here, we used spinning-disk confocal and lattice light-sheet microscopy to study the assembly dynamics of coated pits on the dorsal and ventral membranes of migrating U373 glioblastoma cells stably expressing AP2 tagged with enhanced green fluorescence (AP2-EGFP) and on lateral protrusions from immobile SUM159 breast carcinoma cells, gene-edited to express AP2-EGFP. On U373 cells, coated pits initiated on the dorsal membrane at the front of the lamellipodium and at the approximate boundary between the lamellipodium and lamella and continued to grow as they were swept back toward the cell body; coated pits were absent from the corresponding ventral membrane. We observed a similar dorsal/ventral asymmetry on membrane protrusions from SUM159 cells. Stationary coated pits formed and budded on the remainder of the dorsal and ventral surfaces of both types of cells. These observations support a previously proposed model that invokes net membrane deposition at the leading edge due to an imbalance between the endocytic and exocytic membrane flow at the front of a migrating cell. 相似文献
22.
23.
Protective agent, erdosteine, against cisplatin-induced hepatic oxidant injury in rats 总被引:5,自引:0,他引:5
Cisplatin, one of the most active cytotoxic agents against cancer, has several toxicities. Hepatotoxicity is one of them occurred
during high doses treatment. The aim of this study was to determine the effects of erdosteine against cisplatin-induced liver
injury through tissue oxidant/antioxidant parameters and light microscopic evaluation. The rats were randomly divided into
three groups: control (n=5), cisplatin (10 mg/kg, n=6) and cisplatin+erdosteine (50 mg/kg/day oral erdosteine, n=8) groups. The rats were sacrificed at the 5th day of cisplatin treatment. The liver tissues were examined with light microscopy
and oxidant/antioxidant biochemical parameters. The malondialdehyde (MDA) and nitric oxide (NO) levels were increased in the
cisplatin group in comparison with the control and cisplatin+erdosteine groups (p<0.05). There was no significant difference in MDA and NO levels between control and cisplatin+erdosteine groups. The activities
of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were higher in cisplatin+erdosteine group
than cisplatin group (p<0.05). However, the CAT and GSH-Px activities were significantly lower in cisplatin group than in control group (p<0.05). The light microscopic examination revealed that cytoplasmic changes especially around cells of central vein were observed
in cisplatin group. Hepatocellular vacuolization was seen in these cells. In the cisplatin plus erdosteine group, a decrease
in cytoplasmic changes with the hepatocytes and sinusoidal dilatations around cells of central vein were noticed in as compared
to cisplatin group. In the light of microscopic and biochemical results, it was concluded that cisplatin-induced liver damage
in high dose and erdosteine prevented this toxic side effect by the way of its antioxidant and radical scavenging effects.
(Mol Cell Biochem 278: 79–84, 2005) 相似文献
24.
Lathyrus L.belongs to the tribe Fabeae within the Fabaceae (Leguminosae).It contains more than 200 taxa and has an almost worldwide distribution (Allkin et al.,1986).Tutin & Heywood ( 1981)reported,in Flora Europaea,that 54 species are known from the area.In Flora of Turkey,Davis (1970) stated that the genus is represented by 67 taxa at the species,subspecies,and variety level.However,the number of taxa known from Turkey has since increased to 75 (Davis et al.,1988;Günes & (O)zhatay,2000;Gen(c) & Sahin,2008;Gen(c),2009). 相似文献
25.
Özaslan Ahmet Kayhan Gülsüm İşeri Elvan Ergün Mehmet Ali Güney Esra Perçin Ferda Emriye 《Molecular biology reports》2021,48(11):7371-7378
Molecular Biology Reports - Copy number variants (CNVs) play a key role in the etiology of autism spectrum disorder (ASD). Therefore, recent guidelines recommend chromosomal microarrays (CMAs) as... 相似文献
26.
Kepenek Eda Seyma Ozcinar Evren Tuncay Erkan Akcali Kamil Can Akar Ahmet Ruchan Turan Belma 《Molecular and cellular biochemistry》2020,463(1-2):33-44
Molecular and Cellular Biochemistry - Excitation–contraction coupling in normal cardiac function is performed with well balanced and coordinated functioning but with complex dynamic... 相似文献
27.
Ö. Şimşek A. H. Çon N. Akkoç P. E. J. Saris Mustafa Akçelik 《Journal of industrial microbiology & biotechnology》2009,36(4):481-490
Nisin production of three bioengineered strains, (LAC338, LAC339 and LAC340) with immunity (nisFEG) and/or regulation (nisRK) genes of nisin biosynthesis on plasmids in the Lactococcus lactis LL27 nisin producer, was evaluated under pH-controlled and pH-uncontrolled batch fermentations. Optimization studies showed
that fructose and yeast extract yielded the highest nisin activity. The strains LAC338, LAC339, and LAC340 produced 24, 45,
and 44% more nisin, respectively, than wild-type L. lactis LL27 after 12-h incubation. However, sharp decreases in the yield of nisin were observed at the late phase of fermentation
with LAC339 and LL27 in contrast to LAC340 and LAC338 strains for which the high level of nisin could be maintained longer.
Obviously, increasing the copy number of the regulation genes together with immunity genes in the nisin producers retarded
the loss of nisin in the late phase of the fermentation. 相似文献
28.
An improved protocol for the isolation of DNA from dry material of someHesperis specimens is described. The isolated DNA is suitable for random amplification of polymorphic DNA (RAPD) analysis. Different
DNA extraction protocols were examined to determine which might yield DNA from dry leaf tissue ofHesperis specimens. The methods examined include the protocols with hexadecyltrimethylammonium bromide (CTAB) described by Doyle and
Doyle (1987); sodium dodecyl sulfate (SDS) by Dellaporta et al. (1983); and CTAB and SDS, the modified minipreparation, by
Dellaporta et al (1983). None of these procedures yielded DNA of suitable purity for RAPD assay. We established an improved
procedure involving CTAB and enzymatic digestion of proteins and RNA. The recovery of DNA with an average yield of 25 mg/g
of leaf material was possible with this procedure. RAPD bands, which could be used to distinguish amongHesperis specimens, were generated. 相似文献
29.
The aim of this study was to demonstrate the role of curcumin on oxidative stress, cell proliferation and apoptosis in the
rat intestinal mucosa after ischemia/reperfusion (I/R). A total of 30 male Wistar albino rats were divided into three groups:
sham, I/R and I/R+ curcumin; each group contain 10 animals. Sham group animals underwent laparotomy without I/R injury. After
I/R groups animals underwent laparotomy, 1 h of superior mesenteric artery ligation were followed by 1 h of reperfusion. In
the curcumin group, 3 days before I/R, curcumin (100 mg/kg) was administered by gastric gavage. All animals were sacrificed
at the end of reperfusion and intestinal tissues samples were obtained for biochemical and histopathological investigation
in all groups. Curcumin treatment significantly decreased the elevated tissue malondialdehyde levels and increased of reduced
superoxide dismutase, and glutathione peroxidase enzyme activities in intestinal tissues samples. I/R caused severe histopathological
injury including mucosal erosions and villous congestion and hemorrhage. Curcumin treatment significantly attenuated the severity
of intestinal I/R injury, with inhibiting of I/R-induced apoptosis and cell proliferation. These results suggest that curcumin
treatment has a protective effect against intestinal damage induced by intestinal I/R. This protective effect is possibly
due to its ability to inhibit I/R-induced oxidative stress, apoptosis and cell proliferation. 相似文献
30.
Goren AC Bilsel G Bilsel M Demir H Kocabaş EE 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(9-10):687-690
The water-distilled essential oil the leaves of Coridothymus capitatus were analyzed by GC/MS and also analyzed by direct thermal desorption GC/MS. Comparison was made between two analyses techniques. The essential oil consisted mainly of monoterpenes 98.9%, while oxygenated hydrocarbons were identified as 55.6 % and non-oxygenated hydrocarbons as 43.6%. As major components were found carvacrol (35.6%), p-cymene (21.0%), thymol (18.6%), gamma-terpinene (12.3%), alpha-terpinene (3.2%), beta-myrcene (3.0%) and alpha-thujene (1.3%) by hydrodistillation and by the GC/MS method. The direct thermal desorption GC/MS analysis also showed the same major components, namely carvacrol (51.6%), thymol (21.7%), p-cymene (9.7%) gamma-terpinene (8.2%), alpha-terpinene (1.64%). The essential oil of C. capitatus showed strong activity against S. aureus, P. vulgaris, P. aeruginosa, E. coli, K. pneumonia, B. 相似文献