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1.
AIMS--To characterise a new mouse monoclonal antibody, VS38, which recognises an intracytoplasmic antigen of 64 kilodaltons present in normal and neoplastic plasma cells; and to establish its value as a diagnostic reagent for routine pathological practice. METHODS--A range of normal and neoplastic tissue sections, both frozen and routinely fixed, were immunostained, using the microwave method of antigen retrieval for routinely fixed specimens. The antibody was also tested on blood and bone marrow specimens and a range of human cell lines. The molecular weight of the antigen recognised by the antibody was obtained by western blot analysis. FACS analysis was used to demonstrate the cellular location of the antigen and its presence on tonsil cell suspensions and myeloma cases. RESULTS--VS38 recognised normal and neoplastic plasma cells in all of the tissues, including all routinely fixed plasma cell neoplasms tested. The antibody also weakly stained epithelial elements within the tissue but was absent from haemopoietic cells of other lineages. CONCLUSION--Antibody VS38 is of potential value in identifying myeloma or plasmacytoma in bone marrow or other tissues. It differentiates lymphoplasmacytoid lymphoma from lymphocytic and follicular lymphoma. It also subdivides large cell lymphomas into two groups which may be a more reliable method of separating these tumours than morphology alone.  相似文献   
2.
Various combinations of orthodontic force, luxation, and observation are applied to 12 teeth traumatically intruded in 3 large dogs. All showed root resorption to some degree. Early orthodontic repositioning, with luxation if immobile, produced the best recovery.  相似文献   
3.
Lowering of the elevated plasma FFA concentration in 18- 24-h fasted rats with nicotinic acid (NA) caused complete ablation of subsequent glucose-stimulated insulin secretion (GSIS). Although the effect of NA was reversed when the fasting level of total FFA was maintained by coinfusion of soybean oil or lard oil (plus heparin), the more saturated animal fat proved to be far more potent in enhancing GSIS. We therefore examined the influence of individual fatty acids on insulin secretion in the perfused rat pancreas. When present in the perfusion fluid at 0.5 mM (in the context of 1% albumin), the fold stimulation of insulin release from the fasted pancreas in response to 12.5 mM glucose was as follows: octanoate (C8:0), 3.4; linoleate (C18:2 cis/cis), 5.3; oleate (C18:1 cis), 9.4; palmitate (C16:0), 16. 2; and stearate (C18:0), 21.0. The equivalent value for palmitoleate (C16:1 cis) was 3.1. A cis--> trans switch of the double bond in the C16:1 and C18:1 fatty acids had only a modest, if any, impact on their potency. A similar profile emerged with regard to basal insulin secretion (3 mM glucose). When a subset of these fatty acids was tested in pancreases from fed animals, the same rank order of effectiveness at both basal and stimulatory levels of glucose was seen. The findings reaffirm the essentiality of an elevated plasma FFA concentration for GSIS in the fasted rat. They also show, however, that the insulinotropic effect of individual fatty acids spans a remarkably broad range, increasing and decreasing dramatically with chain length and degree of unsaturation, respectively. Thus, for any given level of glucose, insulin secretion will be influenced greatly not only by the combined concentration of all circulating (unbound) FFA, but also by the makeup of this FFA pool. Both factors will likely be important considerations in understanding the complex interplay between the nature of dietary fat and whole body insulin, glucose, and lipid dynamics.  相似文献   
4.
Biochemical evidence that cytokeratins are present in smooth muscle   总被引:2,自引:0,他引:2  
Recent immunocytochemical studies have revealed that cytokeratin intermediate filaments, previously thought to be restricted to epithelial tissues, are present in muscle. In view of the implications of these reports for diagnostic pathology it is important to investigate by biochemical means whether these findings represent the presence of true cytokeratin proteins or an unexpected antigenic cross-reaction. In the present study intermediate filament proteins have been extracted from samples of human myometrium and identified by immunoblotting techniques using well characterized monoclonal antibodies, two against cytokeratins and two against desmin. The results show that the proteins of the appropriate molecular weight for cytokeratin were labelled by anti-cytokeratin antibodies and were quite distinct from those recognized by anti-desmin antibodies. This study therefore confirms previous immunocytochemical findings and emphasizes the need for caution when using anti-intermediate filament antibodies for diagnostic purposes.  相似文献   
5.
RHAMM (Receptor for Hyaluronic Acid Mediated Motility) has been identified as a receptor for the extracellular matrix component hyaluronan (HA) and was recently shown to be essential for the locomotion of normal and transformed peripheral cells. Until now the potential role of RHAMM in the motility of neural-derived cells has not been investigated. Here, we report that cultured primary astrocytes, astrocyte cell lines, and microglia express this receptor and exhibit RHAMM-dependent motility. Immunocytochemical localization of RHAMM showed that it was often present as aggregates at the periphery of cells in contact with one another or concentrated on protruding processes of isolated cells. Glial cells contained 50 and 72 kDa forms of RHAMM, and both of these forms were found to have HA binding capacity. Time lapse imaging of cell locomotion revealed a significant inhibition of motility and process elongation by neutralizing anti-RHAMM antibodies and by peptides corresponding to the HA binding domains of RHAMM. These results demonstrate that RHAMM serves a role in glial cell locomotion in vitro and provide the basis for investigations of the motile behavior of glial cells in vivo after CNS injury.  相似文献   
6.
This study evaluated changes in the profiles of African American women presented in fashion magazines during the 20th century. Twenty-six variables were measured on a total of 119 profile photographs collected from various fashion magazines published in the 1940s through the 1990s. The photographs were divided into 6 groups corresponding to the decade in which they were published. A 1-way analysis of variance was performed, and between-group differences were examined with a Tukey multiple comparison procedure. Significant between-group differences (P <.01) were found for anteroposterior lip position, nasolabial angle, and interlabial angle, with increased fullness and more anteriorly positioned lips in the more recent decades. No significant differences were found for the frontonasal angle, the nasal tip angle, and the relationship of the chin to the upper face (total facial angle). Esthetic standards for the African-American female profile changed during the 20th century and, similar to the standards for the white profile, show a trend toward fuller and more anteriorly positioned lips.  相似文献   
7.
Mediastinitis is a devastating complication following median sternotomy. Continuous povidone-iodine (PVP-I) irrigation has been advocated as therapy because of its broad antimicrobial spectrum and its apparent safety. However, several recent clinical reports have warned of suspected local and systemic iodine toxicity. The purpose of this study is to determine if significant amounts of iodine can be absorbed systemically via the mediastinum, and if so, what toxicity (local and/or systemic) may result. PVP-I (0.5%) was continuously irrigated into the pericardial sacs of three dogs via catheters for 48 hr. Serial serum and urine iodine levels were determined. The serum steady-state concentration (Css), the rate elimination constant (k), the urinary clearance (Cl), and the serum half-life (t 1/2) for iodine were assessed. Serum electrolytes, Bun, Cr, and arterial pH were measured to assess systemic iodine toxicity. Tissue samples of the heart, pericardium, liver, and kidney were examined histologically for evidence of local or end-organ iodine toxicity. This study demonstrated that the absorption of iodine during continuous mediastinal irrigation with PVP-I follows zero-order pharmacokinetics, just as if it were being given by continuous intravenous infusion. The baseline serum iodine concentration was 145.9 +/- 64.3 micrograms/dl, Css was 29,290 +/- 101.4 micrograms/dl, k was 0.0996 +/- 0.009/hr, Cl was 872.4 +/- 119.3 ml/hr, and t1/2 was 6.22 hr. Urinary excretion of iodine increased in proportion to the serum iodine. Measured serum chloride increased in a linear manner (r = 0.949), while serum Na, K, Bun, Cr, and pH were unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
AIMS--To establish whether PAb248 recognises human p53 as well as murine p53 and if so, to determine its distribution in normal tissues. METHODS--The ability of PAb248 to recognise human p53 was established by analysis of the human osteosarcoma derived Saos-2 cell line, which lacks the p53 gene, before and after transfection with p53 cDNA, using western blotting and immunoprecipitation. Immunostaining on normal tissues and cell lines was carried out using an immunoperoxidase technique. The two anti-p53 antibodies PAb 240 and DO-7 were used as controls. RESULTS--The anti-p53 PAb248 monoclonal antibody stained the Saos-2 cell line after, but not before, transfection with p53 cDNA. Both western blots and immunoprecipitations performed with this antibody revealed a 53,000 molecular weight band. With immunostaining, this antibody detects p53 protein in most lymphoid and human epithelial cells in a cytoplasmic-perinuclear localisation that has not been described before. In the same tissues nuclear staining could be seen in a few scattered cells using the PAb240 antibody. The topographical distribution of wild type p53 was not related to proliferating areas but, rather, to short-lived populations of cells. CONCLUSIONS--Immunostaining of wild type p53 is demonstrable not only in its nuclear form using antibody PAb240 but also in it common cytoplasmic-perinuclear localisation in normal tissues using the PAb248 monoclonal antibody. This opens up new possibilities for its study in both physiological and pathological conditions.  相似文献   
9.
10.
Vascular endothelial growth factor (VEGF)-A is an important angiogenic factor in establishing the vasculature in renal cell carcinomas (RCCs). Since little is known about VEGF signalling in RCCs, the profile of phosphorylated KDR (pKDR) has been investigated and the intracellular location of the receptor has been examined in the present study. Using two monoclonal antibodies raised against the phosphorylated KDR epitopes (Y1059 and Y1214) known to mediate different VEGF functions, together with a commercial anti-KDR antibody and immunohistochemistry, the expression of pKDR was investigated in a series of normal (n = 25) and neoplastic kidneys (n = 54; clear cell n = 35; papillary n = 10; oncocytomas n = 8). pKDR was present in many tissue elements of both normal and neoplastic renal tissues, with strong expression in the cell membrane, cytoplasm, and nuclei of normal kidney and tumour cells, as well as endothelial cells in tumours of all histological types. Patterns and intensity were similar using both anti-pKDR antibodies. There was no significant correlation in clear cell carcinomas between pKDR expression and age (p = 0.57), tumour size (p = 0.2), gender (p = 0.59), grade (p = 0.2) or histological type (p = 0.36). To delineate further the intracellular processing that might account for the cellular distribution, confocal microscopy was also performed. Antibodies to the different phosphorylated epitopes demonstrated different intracellular staining patterns. This study shows that pKDR is present in a wide variety of renal tumours, suggesting that anti-VEGF therapy might have direct effects on tumour cells. It further suggests that cells traffic pKDR depending on the precise KDR tyrosines that are autophosphorylated in a manner that enables receptor activation to result in different functions.  相似文献   
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