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101.
Umemura YM Vrljic M Nishimura SY Fujiwara TK Suzuki KG Kusumi A 《Biophysical journal》2008,95(1):435-450
Previously, investigations using single-fluorescent-molecule tracking at frame rates of up to 65 Hz, showed that the transmembrane MHC class II protein and its GPI-anchored modified form expressed in CHO cells undergo simple Brownian diffusion, without any influence of actin depolymerization with cytochalasin D. These results are at apparent variance with the view that GPI-anchored proteins stay with cholesterol-enriched raft domains, as well as with the observation that both lipids and transmembrane proteins undergo short-term confined diffusion within a compartment and long-term hop diffusion between compartments. Here, this apparent discrepancy has been resolved by reexamining the same paradigm, by using both high-speed single-particle tracking (50 kHz) and single fluorescent-molecule tracking (30 Hz). Both molecules exhibited rapid hop diffusion between 40-nm compartments, with an average dwell time of 1-3 ms in each compartment. Cytochalasin D hardly affected the hop diffusion, consistent with previous observations, whereas latrunculin A increased the compartment sizes with concomitant decreases of the hop rates, which led to an ∼50% increase in the median macroscopic diffusion coefficient. These results indicate that the actin-based membrane skeleton influences the diffusion of both transmembrane and GPI-anchored proteins. 相似文献
102.
The aim of this study was to explore the expression of cancer/testis tumor associated antigens (C/T TAAs) MAGE-A 3/4 and NY-ESO-1 in lung squamous cell carcinoma and adenocarcinoma, and to evaluate their association with the standard clinical-pathological features of surgically treated lung cancer patients. The study included 80 patients with non-small cell lung cancer (40 adenocarcinomas, 40 squamous cell carcinomas) who had undergone surgery in the period between 2002 and 2005. The MAGE-A3/4 and NY-ESO-1 antigen expression was analyzed immunohistochemically (IHC). The results showed MAGE-A3/4 and NY-ESO-1 positive staining in 65.1% and 23.3% of squamous cell carcinomas and 18.9% and 10.8% of adenocarcinomas, respectively. A statistically higher MAGE-A3/4 expression was observed in planocellular bronchial carcinoma (p < 0.001), while no difference was found in the expression of NY-ESO-1 in adenocarcinoma and planocellular carcinoma (p = 0.144). A significant association was found between the MAGE-A3/4 expression and presence of tumor necrosis in squamous cell cancer specimens (p = 0.001), but not in adenocarcinoma (p = 0.033). A statistically significant association was noted between the NY-ESO-1 expression and positive hilar and mediastinal lymph nodes in adenocarcinoma (p = 0.025) whereas it was not the case in squamous cell carcinoma. Non-small cell lung cancer frequently expresses cancer/testis tumor associated antigens. Our results demonstrate that the MAGE-A3/4 and NY-ESO-1 expression was significant associated with prognostic factors of poor outcome of disease (presence of tumor necrosis and lymph node metastasis). As C/T antigens are important for inducing a specific immune reaction in lung cancer patients, there is an intention to form a subgroup of patients in the future, whose treatment would be enhanced by specific immunotherapy based on the observed scientific results. 相似文献
103.
Simultaneous and stepwise deprotection of the fully benzylated D-glucosyl esters of 1-benzyl N-benzyloxycarbonyl- and N-tert-butyloxycarbonyl-L-glutamic acid (1 and 5, respectively) have been examined. Catalytic hydrogenation of 1 led to intramolecular aminolysis to give pyroglutamic acid and D-glucose, but similar treatment in the presence of trifluoroacetic acid afforded both anomers of 1-O-(L-gamma-glutamyl)-D-glucopyranose, which were characterized as trifluoroacetates (2alpha and 2beta) and converted into 2,3,4,6-tetra-O-acetyl-1-O-[1-methyl N-(acetyl)-L-glutam-5-oyl]-D-glucopyranose (4) which was also prepared by a definitive method. Hydrogenolysis of 5 gave both anomers of 1-O-[N-(tert-butyloxycarbonyl)-L-gamma-glutamyl]-D-glucopyranose (6), which, upon treatment with trifluoroacetic acid at - 10 degrees, afforded 2alpha and 2beta, respectively. The structure of 6beta was established by its conversion into 2,3,4,6-tetra-O-acetyl-1-O-[1-methyl N-(tert-butyloxycarbonyl)-L-glutam-5-oyl]-beta-D-glucopyranose (7beta), whereas similar treatment of 6alpha gave a mixture of 1,3,4,6-tetra-O-acetyl-2-O-[1-methyl N-(tert-butyloxycarbonyl)-L-glutam-5-oyl]-alpha-D-glucopyranose (9) and 7alpha. A 1 leads to 2 acyl migration occurred during esterification of the aglycon carboxyl group of 6alpha with diazomethane to give 2-O-[1-methyl N-(tert-butyloxycarbonyl)-L-glutam-5-oyl]-alpha-D-glucopyranose (8). 相似文献
104.
Mihanović M Restek-Petrović B Babić G Sain I Telarović S Zilić-Dzeba J 《Collegium antropologicum》2004,28(1):385-391
Schizophrenia and other psychotic disorders as well as the delirium caused by abstinence from alcohol and accute state of drunkenness appear at the very top of the list of factors, which are positively correlated with involuntary hospitalization of patients. This is at the same time a confirmation of the data found in literature considering psychosis an essential factor of involuntary hospitalization; the same referring to the male sex was not, however, confirmed by the results obtained in the first and second research period. Regarding the positive correlation between schizophrenia and other psychotic disturbances, dementia, delirium and other cognitive impairments including the delirium caused by abstinence from alcohol and an accute state of drunkenness on the one side and the high rate of involuntary hospitalization on the other, there is no statistically significant difference between the period preceding and the period following the alterations and amendments to the Law on the protection of patients with mental disorders. 相似文献
105.
In contrast to cold and eurythermal waters, benthic communities of warm brooks in temperate regions have been inadequately
studied. In order to investigate the effects of water thermal regime on the benthic communities of warm waters and their relationships
with those of cold and eurythermic ones, the macrozoobenthos was studied at eight sites in the Toplica River, and at four
sites in its tributary, the Termalni brook. Investigations were carried out seasonally from April 2000 to January 2001. Warm
waters of the Termalni brook were characterized by specific macrozoobenthos assemblages that exhibited significant differences
to the populations of eurythermal and cold waters of the Toplica River. The dominant taxa in the macrozoobenthos community
of warm waters were mainly Gastropoda species. Moreover, benthic communities of warm waters were characterized by lower diversity
and greater biomass in comparison with those of cold and eurythermal waters. The gradient of average annual temperatures represented
the main ecological factor influencing changes of diversity and biomass along the course of the investigated Termalni brook.
Inflow of warm waters at site T6 lead to a decrease in macrozoobenthos abundance and changes in qualitative and quantitative composition of the benthocoenosis
of a highland stream, but did not significantly alter diversity. 相似文献
106.
Skerk V Cajić V Markovinović L Roglić S Zekan S Skerk V Radosević V Tambić Andragević A 《Collegium antropologicum》2006,30(Z2):145-149
A total of 835 patients with symptoms of chronic prostatitis syndrome and no evidence of structural or functional lower genitourinary tract abnormalities were examined in a three year period at the Outpatient Department for Urogenital Infections, University Hospital for Infectious Diseases "Dr. Fran Mihaljevi?" Zagreb, Croatia. Disease etiology was determined in 482 (57.72%) patients. Chlamydia trachomatis was proved to be the causative pathogen in 161 patients, Trichomonas vaginalis in 85, Escherichia coli in 68, Enterococcus in 51, Proteus mirabilis in 20, Klebsiella pneumoniae in 9, Streptococcus agalactiae in 15, Ureaplasma urealyticum in 49 patients with chronic prostatitis. Other patients had mixed infection. In 257 (53.32%) of 482 patients, the inflammatory finding (>10 WBCs/hpf) was found in EPS or VB3. Normal WBCs/hpf (<10) was found in 103 (63.98%) of 161 patients with symptoms of chronic prostatitis in whom C. trachomatis was detected in EPS or VB3, in 50 (58.82%) of 85 patients in whom Trichomonas vaginalis was isolated, and in 23 (46.94%) of 49 patients in whom Ureaplasma urealyticum was isolated. 相似文献
107.
The aim of this study was to assess the quality of life children after cardiac surgery for congenital heart disease (CHD) and to compare these results with healthy children. To assess the quality of life children after surgery for CHD we performed a cross-sectional study of 114 patients who were patients at the Department of Paediatrics in Tuzla, between the ages of 2 and 18 years, of both sexes, and with one of their parents. We used the "PedsQL 4.0 Generic Core Scales", with both child self-report and parent proxy-reports. By self assessment, the PedsQL total scores for quality of life were statistically significantly different between children after cardiac surgery for ages 13 to 18 years and healthy children, while by parent report PedsQL total scores were statistically significantly different between children after cardiac surgery for ages 5 to 7 years and healthy children. By self assessment, children after cardiac surgery for ages from 5 to 7 and 13 to 18 years reported that they have a statistically significantly lower quality of life in the segment school functioning compared to the healthy children. By parental assessment, children after cardiac surgery for ages 2 to 4, 5 to 7 and 8 to 12 years have a statistically significantly lower quality of life in the segments of physical and psychosocial health, emotional, social and school functioning. The results of our study indicate that children after cardiac surgery for CHD by self and parent assessment have a lower quality of life than healthy children. 相似文献
108.
The influence of coumestrol,zearalenone, and genistein administration on insulin receptors and insulin secretion in ovariectomized rats 总被引:2,自引:0,他引:2
Nogowski L Nowak KW Kaczmarek P Maćkowiak P 《Journal of receptor and signal transduction research》2002,22(1-4):449-457
The influence of phytoestrogens (genistein and coumestrol) and mycoestrogen (zearalenone) on insulin secretion, liver insulin receptors and some aspects of lipid and carbohydrate metabolism were investigated in this study. Ovariectomized rats were injected s.c. with the above mentioned compounds in the amount of 1 mg for three days. Coumestrol and zearalenone caused a significant increase in uterus weight, similar to the effects observed after estrone action, while this effect was not observed after the genistein injection. Blood insulin level was not changed after phyto- or mycoestrogen treatment. However, coumestrol and genistein significantly decreased the binding capacity of liver insulin receptors. These changes corresponded with alterations in glucose and free fatty acids profiles in blood, as well as with glycogen content in liver. The effects observed after genistein and coumestrol injections differed from those noticed in rats treated with zearalenone or estrone. On the basis of these results we conclude that metabolic effects of high doses of coumestrol and genistein in ovariectomized rats are partly mediated by changes in insulin sensitivity of the liver and that the action of plant estrogens on metabolism is, at least to the some degree, independent of their estrogen activity. 相似文献
109.
Knezević A Travan S Tarle Z Sutalo J Janković B Ciglar I 《Collegium antropologicum》2002,26(2):667-672
The form of primary and permanent teeth can differ morphologically from that which is considered normal, completely or in some parts. The changes in tooth form can be hereditary or caused by some disease or trauma. Fusion is a union of one or more teeth during development. Gemination means that two separate morphological units were created by division of the tooth germ. The intention of this study was to state the prevalence of double teeth (fusion and gemination) among the persons tested, as to gender, distribution in the maxilla or mandible, and whether the anomaly occurred bilaterally or unilaterally. The results of this investigation have shown that in a total of examined 3,517 plaster models, a prevalence of double teeth was 0.2%. 57.2% of them were fusioned and 42.9% geminated. 相似文献
110.