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1.
NIH3T3 cells transfected with an activated Ha-ras oncogene were treated with L-PHA, the leukoagglutinin from red kidney beans. Cell lines resistant to L-PHA-mediated cytotoxicity were isolated and found to contain reduced levels of L-PHA-binding oligosaccharides. The levels of N-acetylglucosaminyltransferase V, the enzyme responsible for the initiation of the1–6 branch, were reduced in L-PHA-resistant cells. Tumorigenicity in nude mice was unchanged by the change in oligosaccharide expression, but the ability to form lung tumors after intravenous injection was significantly reduced. These results demonstrate that the ability of NIH3T3 cells transfected with an activated Ha-ras oncogene to form lung tumors after intravenous injection into nude mice is reduced in all six L-PHA selected cell lines containing a reduction in1–6 branched Asn-linked oligosaccharides.  相似文献   
2.
The expression of -GlcNAcβ1–6Man-(β1–6) branched oligosaccharides In carcinoma cells has been considered to influence their metastatic potentials. In the present paper, the lectin histochemistry of oral squamous cell carcinomas obtained in biopsy from 34 patients with Phaseolus vulgaris leukoagglutinin (L-PHA), which potentially binds to N-glycosidic carbohydrates with β1–6 linked lactosamin antennae, was studied in order to analyze the relationship between their staining patterns and metastases. The L-PHA-binding oligosaccharides of the carcinomas were expressed on the cell surface in the following patterns: (i) all cells were positive for the staining ('positive'); (ii) some cells were positive but the rest of the carcinoma cells were negative ('weakly positive'); and (iii) all were negative ('negative'). Statistical analysis revealed that the incidence of the metastasis to regional lymph nodes in the 'positive' cases was significantly higher than that in the 'negative' cases. Moreover, the number of the CD14 positive cells including macrophages in the Stroma adjacent to the cardnomas in the 'positive' cases was less than that in the 'negative' or 'weakly positive' cases. The expression of L-PHA-binding oligosaccharides in oral squamous cell carcinoma may be responsible for their metastatic potential to regional lymph nodes, possibly Including their ability to escape macrophage recognition.  相似文献   
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Summary The main dolichol diphosphate-bound oligosaccharides present in primary cultures of both normal and tumor mouse mammary epithelial cells had the same size, yielded the same pattern after acetolysis and paper chromatography, had the same number of mannose residues susceptible to-mannosidase degradation, and were composed of the same monosaccharide residues. This is the first demonstration that normal and tumor mammary cells have dolichol diphosphate-bound oligosaccharides with very similar, if not identical, structures. These compounds are intermediates in the synthesis of asparagine-linked oligosaccharides. On the other hand, normal and tumor cells showed differences in the specific activities of the enzymes involved in the transfer of the distal monosaccharides from the sugar nucleotides to glycoproteins. Sialyl- and fucosyl-transferases were elevated and galactosyl- and N-acetylglucosaminyltransferases were diminished in mammary tumor cells. The intact tumor cells showed an increased fucosylation of glycoproteins of the asparagine-linkage type. Address for reprints: Roberto L. Ceriani, M.D., Ph.D., Bruce Lyon Memorial Research Laboratory, Children's Hospital Medical Center, 51st and Grove Streets, Oakland, CA 94609, USA.  相似文献   
5.
地黄寡糖抗糖尿病药理作用及机制研究回顾   总被引:4,自引:0,他引:4  
现代医学对糖代谢的过程及其调节机制已较明确,并正在走向深入。糖代谢是机体自稳机能(homoostasis)的一个重要方面,Besedovsky等(1977)以神经内分泌系统与免疫系统之间的相互作用及其物质基础为依据,提出了“神经内分泌免疫调节”(neuroenctocrine-immuno-modulation,NIM)网络学说,这个学说的实质是机体神经系统、内分泌系统与免疫系统之间具有共  相似文献   
6.
Irritable bowel syndrome (IBS) is associated with diverse pathophysiologic mechanisms. These mechanisms include increased abnormal colonic motility or transit, intestinal or colorectal sensation, increased colonic bile acid concentration, and superficial colonic mucosal inflammation, as well as epithelial barrier dysfunction, neurohormonal up-regulation, and activation of secretory processes in the epithelial layer. Novel approaches to treatment include lifestyle modification, changes in diet, probiotics, and pharmacotherapy directed to the motility, sensation, and intraluminal milieu of patients with IBS. Despite recent advances, there is a need for development of new treatments to relieve pain in IBS without deleterious central or other adverse effects.  相似文献   
7.
婴儿期是肠道菌群形成和发展最为关键的时期,作为肠道菌群演替速度较快的重要阶段,稳定的肠道菌群定植对机体健康、免疫系统的建立及完善有着重大且长远的意义。母乳中富含人乳低聚糖(HMOs),能够有效促进婴儿肠道中有益细菌的生长,抑制病原菌的侵袭,改善肠道菌群组成,提高菌种多样性,促进婴儿生长发育。现就HMOs的研究现状及其对婴儿肠道菌群的影响进行综述。  相似文献   
8.
AimMOGS mutations cause congenital disorders of glycosylation type IIb (CDG-IIb or GCS1-CDG). The specific manifestations caused by the mutations in this gene remain unknown. We aimed to describe the clinical features of CDG- IIb and the effectiveness of urinary oligosaccharide analysis in the diagnosis of CDG- IIb.MethodsPatient 1 was analyzed with whole-exome sequencing (WES) to identify the causative gene of intractable epilepsy and severe developmental delay. After detecting MOGS mutation in patient 1, we analyzed patients 2 and 3 who were siblings and had clinical features similar to those in patient 1. Urinary oligosaccharide analysis was performed to confirm CDG- IIb diagnosis in patient 1. The clinical features of these patients were analyzed and compared with those in eight published cases.ResultsOur three patients presented with early infantile epileptic encephalopathy, generalized hypotonia, hepatic dysfunction and dysmorphic features. In two cases, compound heterozygous mutations in MOGS were identified by WES. Isolation and characterization of the urinary oligosaccharide was performed in one of these cases to confirm the diagnosis of CDG-IIb. Although the isoelectric focusing of transferrin (IEF-T) of serum in this patient was normal, urinary excretion of Hex4 corresponding to Glc3Man was observed by mass spectrometry.ConclusionThis report provides clinical manifestations of CDG-IIb with MOGS mutation. CDG-IIb shows a normal IEF profile of serum transferrin and cannot be detected by structural analysis of the patient’s glycoproteins. Characterization of urinary oligosaccharides should be considered to detect this disorder.  相似文献   
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Immature seeds of five bean cultivars (flageolet-type and those intended for dry-seed production) were assessed for changes in water-soluble carbohydrates including raffinose family oligosaccharides (RFOs) due to boiling, sterilization, and storage of the sterilized product. About 100?g fresh weight of edible portion of fresh bean seeds contained 2449.3–3182.6?mg total soluble sugars, of which RFOs comprised 44–49%. The highest amounts of these compounds were found in the seeds of the cultivars Laponia and Mona. The dominant oligosaccharide was stachyose. Boiling fresh seeds to consumption consistency reduced total soluble sugars and RFOs: average values were 57% and 55%, respectively. Sterilization in cans resulted in 65% reductions of both total soluble sugars and RFOs. In general, there were no changes in the content of soluble sugars in canned and sterilized products stored for 12?months.  相似文献   
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