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11.
B lymphoblastoid cell lines with normal and defective O-glycosylation established from an individual with blood group Tn 总被引:2,自引:0,他引:2
Individuals with the Tn blood group contain terminal serine/threonine- linked N-acetylgalactosamine residues in their blood cells. This is due to lack of UDP-D-galactose: D-N-acetyl galactosamine beta-D-galactosyl transferase from part of their red cells and probably from their leukocytes. We have established B lymphoblastoid cell lines from such an individual by in vitro infection of his lymphocytes with Epstein- Barr virus. The original line contained a mixture of cells reactive and nonreactive with Helix pomatia lectin (Hp). These cells were subcloned after staining with fluorescent Hp by a fluorescence-activated cell sorter (FACS) into homogeneous, phenotypically stable lines of Hp- positive (Hp+) and Hp-negative (Hp-) cells. The molecular differences between the membrane glycoproteins were characterized by carbohydrate- specific surface labeling techniques, Hp affinity chromatography, polyacrylamide slab gel electrophoresis and glycopeptide/oligosaccharide analysis. The major O-glycosidic membrane glycoprotein (GP105) was retained on Hp-Sepharose columns only from Hp+ cells, whereas the common leukocyte antigen (GP160-200) was partially retained on Hp columns from both lines. These proteins were isolated by immune precipitation with monoclonal antibodies and characterized. The results show that the GP105 glycoprotein from Hp+ cells contains terminal N-acetylgalactosamine residues but also more complex oligosaccharides. The common leukocyte antigen showed different electrophoretic mobilities in Hp+ and Hp- cells. UDP-galactose D-N- acetyl galactosamine beta-galactosyl transferase was almost absent in the Hp+ cells. These cell lines are useful for studies on the functional role and regulation of the biosynthesis of O-glycosidic carbohydrates. 相似文献
12.
Oxidative metabolism of the human eosinophil 总被引:14,自引:1,他引:14
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst. 相似文献
13.
A humanised tissue‐engineered bone model allows species‐specific breast cancer‐related bone metastasis in vivo 下载免费PDF全文
VMC Quent AV Taubenberger JC Reichert LC Martine JA Clements DW Hutmacher D Loessner 《Journal of tissue engineering and regenerative medicine》2018,12(2):494-504
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients. 相似文献
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Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after surgery.Improvements in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover,changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field. 相似文献
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Forty-one proved cases of acute acalculous cholecystitis imaged with technetium-99m iminodiacetic acid (IDA) cholescintigraphy were retrospectively analyzed. After the exclusion of one indeterminate scan (showing poor initial hepatic uptake and excretion), the study yielded a 92.5% (37 of 40) sensitivity for the detection of cystic or common bile duct obstruction. Each of the three patients with false-negative scintigrams had other abnormal scintigraphic findings suggestive of biliary tract disease. Of the 20 patients (48.8%) with focal or diffuse gangrenous cholecystitis or perforation, seven (35%) exhibited either free peritoneal spill or increased pericholecystic activity to indicate the presence of advanced disease. 相似文献
18.
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography. 相似文献
19.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
20.
WH Belloso LC Orellana B Grinsztejn JS Madero A La Rosa VG Veloso J Sanchez R Ismerio Moreira B Crabtree‐Ramirez O Garcia Messina MB Lasala J Peinado MH Losso 《HIV medicine》2010,11(9):554-564