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111.
N-glycoproteins bearing beta1-6 branched oligosaccharides from the A375 human melanoma cell line analysed by tandem mass spectrometry 总被引:1,自引:0,他引:1
Tumour-associated alterations of cell surface glycosylation play a crucial role in the adhesion and metastasis of cancer cells. It is well known that the metastatic potential is associated with increased GlcNAc beta1-6 branching in N-glycans of tumour cells specifically recognized by a lectin from Phaseolus vulgaris leukoagglutinin (PHA-L). We identified proteins bearing GlcNAc beta1-6 branched N-glycans in the A375 human melanoma cell line by affinity chromatography separation on a PHA-L agarose column, followed by immunoidentification and tandem mass spectrometry (MS/MS) analysis. Amongst the proteins identified were integrin subunits alpha2, alpha3, alpha5 and beta1, as well as N-cadherin and lysosome-associated membrane proteins (LAMP-1 and LAMP-2). In addition, L1, Mac-2 binding protein (Mac-2-BP), activated leukocyte cell adhesion molecule/CD166 (ALCAM) and melanotransferrin were shown to react with PHA-L. Some of these proteins are connected mainly with nervous tissues or the immune system and play a crucial role in cell adhesion processes. The presence of GlcNAc beta1-6 branched oligosaccharides in these proteins may influence their adhesion properties, reducing adhesion of the cells to the extracellular matrix (ECM) and thus facilitating tumour cell invasion. 相似文献
112.
113.
Mazur B Olejnik I Wylezol I Sonta-Jakimczyk D Szczepanski T Karpe J 《Pediatric hematology and oncology》2003,20(4):303-308
The immunosuppressive effect of cytostatics, basic therapeutic agents in the treatment of proliferative diseases of the hematopoietic system, and the rising number of children cured from acute leukaemias form together a need to monitor the status of the immune system following cessation of therapy. Surface antigens in lymphocytes from peripheral blood were assessed in 16 children directly after intensive chemotherapy (i.e., after protocol II of the BMF program) and in 25 children 12-13 months following conclusion of acute lymphoblastic leukemia treatment. The results were compared to data obtained from children never afflicted with neoplastic disease. A significant decrease in the average number of lymphocyte subpopulations was noted in the case of the treated children directly after intensive chemotherapy. The average values of lymphocyte subpopulations in children with concluded treatment are within the norm, with the exception of NK and TS lymphocytes. 相似文献
114.
hNedd4 and Rsp5p are orthologous ubiquitin ligases that contain a catalytic Hect domain, a C2 domain and multiple WW domains that mediate interactions with proteins. hNedd4 associates with the epithelial sodium channel and mutations disrupting this interaction lead to Liddle's syndrome, a heritable hypertension. Yeast Rsp5p ubiquitinates plasma membrane receptors and transporters and regulates their endocytosis. To determine whether the human enzyme has activity in yeast, hNEDD4 was expressed in yeast from the RSP5 or GAL1/10 promoters. Ectopic hNedd4 improved the growth and partially suppressed the endocytosis defect of rsp5 mutant cells, although it did not restore the viability of the rsp5-delta strain. Wild-type cells harboring hNedd4 grew better at elevated temperature and on media containing cycloheximide. In contrast, hNedd4 WW domain mutants inhibited the growth of yeast when expressed at high levels. Our results show that hNedd4 affects cell growth, endocytosis and cycloheximide tolerance of yeast cells. 相似文献
115.
Pregnancy induced hypertension (PIH) is accompanied by injury and further activation of placental endothelial cells. Activated endothelial cells produce several mediators, among them endothelin-1 (ET-1)--one of the most potent vasoconstrictors. The aim of the study was to examine the ET-1 level in serum of 18 women with PIH and compare it to the group of 16 normotensive pregnant women. ET-1 level, as evaluated by ELISA test, was significantly higher in PIH than in normotensive pregnancy, 33.00 +/- 12.07 vs. 25.00 +/- 5.69 pg/mL (p = 0.005), respectively. It might be concluded, that ET-1 level is a prognostic parameter, indicating the possibility of PIH development. 相似文献
116.
Does acupuncture improve the orthopedic management of chronic low back pain--a randomized,blinded, controlled trial with 3 months follow up 总被引:3,自引:0,他引:3
This prospective, randomised controlled trial, with three parallel groups, patient and observer blinded for verum and sham acupuncture and a follow up of 3 months raises the question: "Does a combination of acupuncture and conservative orthopedic treatment improve conservative orthopedic treatment in chronic low back pain (LBP). 186 in-patients of a LBP rehabilitation center with a history of LBP >or=6 weeks, VAS >or=50mm, and no pending compensation claims, were selected; for the three random group 4 weeks of treatment was applied. 174 patients met the protocol criteria and reported after treatment, 124 reported after 3 months follow up. Patients were assorted 4 strata: chronic LBP, or=5 years. Analysis was by intention to treat. Group 1 (Verum+COT) received 12 treatments of verum acupuncture and conservative orthopedic treatment (COT). Group 2 (Sham+COT) received 12 treatments of non-specific needling and COT. Group 3 (nil+COT) received COT alone. Verum- and Sham acupuncture were blinded against patient and examiner. The primary endpoints were pain reduction >or=50% on VAS 3 months after the end of the treatment protocol. Secondary endpoints were pain reduction >or=50% on VAS and treatment efficacy on a four-point box scale directly after the end of the treatment protocol and treatment efficacy after 3 months. In the whole sample a pain relief of >or=50% on VAS was reported directly after the end of treatment protocol: Verum+COT 65% (95%CI 51-77%), Sham+COT 34% (95%ci 22-49%), nil+COT 43% (95%ci 29-58%) - results are significant for Verum+COT over Sham+COT (P相似文献
117.
We present a case of a 65-year-old female admitted to the hospital due to severe intracranial hemorrhagia complicated by recurrences of polymorphic ventricular tachycardia of torsade de pointes type. ECG showed a marked prolongation of QT interval and giant U waves. The potassium level was 2.9 mmol/l and magnesium level - 0.6 mmol/l. Intravenous lidocaine and magnesium caused a complete supression of arrhythmia. Unfortunately, the patient died three days later due to cerebral damage and respiratory failure. 相似文献
118.
Loesch DZ Huggins RM Bui QM Epstein JL Taylor AK Hagerman RJ 《Journal of developmental and behavioral pediatrics : JDBP》2002,23(6):416-423
The effect of the fragile X mental retardation 1 (FMR1) gene product (fragile X mental retardation protein [FMRP]) deficits on Full-Scale IQ (FSIQ) and FSIQ-adjusted Wechsler subtests and index scores in fragile X disorder were assessed using a robust modification of the maximum likelihood estimators for pedigree data. The results from 144 extended families have demonstrated a linear effect of progressively reduced levels of FMRP on the FSIQ and all subtest and summary scores in either gender. The effect of FMRP in decreasing FSIQ-adjusted subtest scores was highly significant for Digit Span, Symbol Search, Object Assembly, and Picture Arrangement, with a consistent trend in both genders. Heritability for FSIQ and unadjusted subtest scores estimated from the covariance model did not exceed 50% and varied widely from the highest for Verbal score to the lowest for Picture Completion score. Possible mechanisms by which FMRP deficit impacts on specific weaknesses in fragile X are considered on the basis of present data. 相似文献
119.
Pieńkowska-Machoy E Karczewicz D Torbus-Lisiecka B Chełstowski K 《Klinika oczna》2003,105(3-4):166-170
PURPOSE: The aim of the work was, to find out the relations between the lipid profile and glycosylated hemoglobin in blood and eye changes in the diabetic young people. MATERIAL AND METHODS: There were 39 patients (19 women and 20 men), aged 14-27 years (mean 19.5), treated for diabetes during the period 6-23 years (mean 9.6). The ophthalmological examinations have included anterior segment and lens, as well as the fundus of the eye. There also have been made the blood serum examinations of cholesterol (CHC), LDL-CHC, HDL-CHC, trigliceride (TG), apolipoproteins B (ApoB) and glycosylated hemoglobin (HbA1c). RESULTS: Basing on these examinations it has been stated that: 1. the lens changes were observed in the patients of increased LDL-CHC level and ApoB, who suffered from diabetes shorter than 10 years, while in the patients suffering longer, lens changes correlate with the high level of HbA1c; 2. the eye fundus changes correlated substantially in the patients with the high levels of HbA1c, TG, HDL-CH (negatively), LDL-CH and ApoB, suffering less than 10 years; in the patients suffering longer, correlation was also with the increased level of HbA1c, CHC and LDL-CHC. 3. The increased levels of lipids were noted in the patients with the high level of HbA1c. CONCLUSIONS: The stated data have indicated, that the eye changes are caused by disturbances of lipid parameters, but besides of the glycaemia disorders. The diabetic duration does not matter for the lipid profile and HbA1c level, but it is important for the occurrence of eye fundus changes. The HbA1c essentially influences on the occurrence of eye fundus changes, but in the longer suffering patients, also on the lens changes. The high HbA1c level shifts the lipid profile towards atherogenic factors. It is purposeful, to decrease its level below 7%, which is accepted as good diabetes control. 相似文献
120.
The efficacy of immunization of a vaccine depends on an antigen, an adjuvant, and on the expression of multiple genes in the host. The responsiveness of various strains of mice to adjuvants is therefore dependent on their genetic background present as a complex, multigenic trait similarly as in man. We have recently developed a gene-discovery platform, termed recombinant congenic strains (RCS), that greatly facilitates the dissection, localization and characterization of genes that mediate complex traits such as responsiveness to adjuvants. These recombinant congenic mice, which were constructed from two progenitor strains (A/J and C57BL/6) that are phenotypically different for several spontaneous or infectious diseases, were generated such that they carry 13.5% of the one genome in 85% of the other genome. The use of these RCS mice therefore enables a more efficient identification of genes that mediate the responsiveness of the adjuvant. 相似文献