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61.
Ibraghimov Alexander R.; Sacco Randy E.; Sandor Matyas; Iakoubov Leonid Z.; Lynch Richard G. 《International immunology》1995,7(11):1763-1769
A population of CD4+ cells has been identified in the murinefemale genital tract (FGT). Phenotypic studies of FGT CD4+ cellsdemonstrate that they express CD3 and that the majority of thesecells are ßTCR+Thy-1+. Most of the Thy-1+CD4+ßTCR+ cells resemble memory T cells based on their expressionof CD44, L-selectin and CD45RB antigens. The vast majority ofThy-1+CD4+ßTCR+ FGT cells are CD5+ and all of themare B220–. Systemic stimuli including infection with Trypanosomabrucel brucel, injection with anti-CD3, or bacterial superantigensstaphylococcal enterotoxin A or B cause a rapid accumulationof CD4+cells in the FGT exceeding that observed for CD4+ cellsin spleen and lymph nodes (LN). Expansion of the FGT CD4+ cells,which are phenotypically distinct from the splenic and LN CD4+T cells, is due to local proliferation rather than an influxof cells from the circulation. The CD4+ population in the FGTof adult nu/nu mice is dramatically reduced, indicating itsthymic dependency. In lpr/lpr mice, FGT CD4 cells do not displaychanges characteristic of splenic or LN CD4 cells in the sameanimals. These findings demonstrate that the CD4+ cells of themurine FGT are thymic dependent, but that they constitute aT cell lineage that phenotypically and, probably functionally,is distinct from other peripheral CD4+ T cell populations. 相似文献
62.
63.
Shivachandra SB Li Q Peachman KK Matyas GR Leppla SH Alving CR Rao M Rao VB 《Vaccine》2007,25(7):1225-1235
We describe a multicomponent antigen display and delivery system using bacteriophage T4. Two dispensable outer capsid proteins, Hoc (highly antigenic outer capsid protein, 155 copies) and Soc (small outer capsid protein, 810 copies), decorate phage T4 capsid. These proteins bind to the symmetrically localized capsid sites, which appear following prohead assembly and expansion. We hypothesized that multiple antigens fused to Hoc can be displayed on the same capsid and such particles can elicit broad immunological responses. Anthrax toxin proteins, protective antigen (PA), lethal factor (LF), and edema factor (EF), and their functional domains, were fused to Hoc with an N-terminal hexa-histidine tag and the recombinant proteins were over-expressed in E. coli and purified. Using a defined in vitro assembly system, the anthrax-Hoc fusion proteins were efficiently displayed on T4 capsid, either individually or in combinations. All of the 155 Hoc binding sites can be occupied by one antigen, or they can be split among two or more antigens by varying their molar ratio in the binding reaction. Immunization of mice with T4 phage carrying PA, LF, and EF elicited strong antigen-specific antibodies against all antigens as well as lethal toxin neutralization titers. The triple antigen T4 phage elicited stronger PA-specific immune responses than the phage displaying PA alone. These features offer novel avenues to develop customized multicomponent vaccines against anthrax and other pathogenic diseases. 相似文献
64.
G R Matyas S A Aaronson R O Brady P H Fishman 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(17):6065-6068
Glycosphingolipid alterations upon viral transformation are well documented. Transformation of mouse 3T3 cells with murine sarcoma viruses results in marked decreases in the levels of gangliosides GM1 and GD1a and an increase in gangliotriaosylceramide. The transforming oncogenes of these viruses have been identified as members of the ras gene family. We analyzed NIH 3T3 cells transfected with human H-, K- and N-ras oncogenes for their glycolipid composition and expression of cell surface gangliosides. Using conventional thin-layer chromatographic analysis, we found that the level of GM3 was increased and that of GD1a was slightly decreased or unchanged, and GM1 was present but not in quantifiable levels. Cell surface levels of GM1 were determined by 125I-labeled cholera toxin binding to intact cells. GD1a was determined by cholera toxin binding to cells treated with sialidase prior to toxin binding. All ras-transfected cells had decreased levels of surface GM1 and GD1a as compared to logarithmically growing normal NIH 3T3 cells. Levels of GM1 and, to a lesser extent, GD1a increased as the latter cells became confluent. Using a monoclonal antibody assay, we found that gangliotriaosylceramide was present in all ras-transfected cells studied but not in logarithmically growing untransfected cells. Interestingly, gangliotriaosylceramide appeared when the latter cells became confluent. These results indicated that ras oncogenes derived from human tumors are capable of inducing alterations in glycolipid composition. 相似文献
65.
Tomanek B Iqbal U Blasiak B Abulrob A Albaghdadi H Matyas JR Ponjevic D Sutherland GR 《Neuro-oncology》2012,14(1):53-63
A mouse model of glioblastoma multiforme was used to determine the accumulation of a targeted contrast agent in tumor vessels. The contrast agent, consisting of superparamagnetic iron oxide coated with dextran, was functionalized with an anti-insulin-like-growth-factor binding protein 7 (anti-IGFBP7) single domain antibody. The near infrared marker, Cy5.5, was also attached for an in vivo fluorescence study. A 9.4T magnetic resonance imaging (MRI) system was used for in vivo studies on days 10 and 11 following tumor inoculation. T(2) relaxation time was used to measure the accumulation of the contrast agent in the tumor. Changes in tumor to brain contrast because of active targeting were compared with a nontargeted contrast agent. Effective targeting was confirmed with near infrared measurements and fluorescent microscopic analysis. The results showed that there was a statistically significant (P < .01) difference in normalized T(2) between healthy brain and tumor tissue 10 min, 1 h, and 2 h point postinjection of the anti-IGFBP7 single domain antibody targeted and nontargeted iron oxide nanoparticles. A statistical difference remained in animals treated with targeted nanoparticles 24 h postinjection only. The MRI, near infrared imaging, and fluorescent microscopy studies showed corresponding spatial and temporal changes. We concluded that the developed anti-IGFBP7-iron oxide single domain antibody-targeted MRI contrast agent selectively binds to abnormal vessels within a glioblastoma. T(2)-weighted MRI and near infrared imaging are able to detect the targeting effects in brain tumors. 相似文献
66.
Timea Hever M.D. Norbert Nemeth M.D. Ph.D. Endre Brath M.D. Laszlo Toth M.D. Ferenc Kiss M.D. Erika Sajtos M.D. Lili Matyas M.D. Janos Szaszko M.D. Laszlo Drimba M.D. Barna Peitl M.D. Ph.D. Zoltan Csiki M.D. Ph.D. Iren Miko M.D. Ph.D. Istvan Furka M.D. Ph.D. D.Sc. 《Microsurgery》2010,30(8):649-656
Artificial femoral arterio‐venous (AV) shunts are widely used in rodent models for studying shunt maturation and to optimize various surgical techniques. However, little is known about complex circulatory, microcirculatory, and hemorheological effects of end‐to‐side saphenous AV shunts. We aimed to study these parameters in mature AV shunts. Studying these questions in CD rats, end‐to‐side anastomoses were made between the left saphenous artery and vein. On the right‐side the nonoperated saphenous vessels served as own control. Furthermore healthy control animals were also investigated. On the 8th to 12th postoperative week microcirculatory and blood flow measurements were performed and blood samples were taken both from the shunt's arterial and venous limbs and from the nonoperated side vessels. Hematological parameters, erythrocyte aggregation, and deformability were determined. The entire shunt and the control vessels were removed for histological examinations. The skin microcirculation on shunt side slightly increased on thigh and decreased on paws versus the nonoperated side. Blood flow measurements made directly on the vessels showed that arterial to venous blood flow rate ratio was 1.59 ± 0.29 on nonoperated side and 1.2 ± 0.13 on the shunt side, and 1.49 ± 0.05 in control animals. Erythrocyte aggregation and deformability worsened on the shunt side. Histologically increased number of smooth muscle elements and connective tissue were found in venous limb of the shunts. The artificial AV shunt between the saphenous artery and vein seems to be a suitable model for further functional‐morphological and hemorheological examinations of hemodialysis in various states and diseases. © 2010 Wiley‐Liss, Inc. Microsurgery 30:649–656, 2010. 相似文献
67.
Carey LM Matyas TA 《American journal of physical medicine & rehabilitation / Association of Academic Physiatrists》2005,84(6):428-442
OBJECTIVE: Task-specific learning typifies perceptual training but limits rehabilitation of sensory deficit after stroke. We therefore investigated spontaneous and procedurally facilitated transfer of training effects within the somatosensory domain after stroke. DESIGN: Ten single-case, multiple-baseline experiments were conducted with stroke participants who had impaired discrimination of touch or limb-position sense. Each experiment comprised three phases: baseline, stimulus-specific training of the primary discrimination stimulus, and either stimulus-specific training of the transfer stimulus or stimulus-generalization training. Both the trained and transfer stimuli were monitored throughout using quantitative, norm-referenced measures. Data were analyzed using individual time-series analysis and meta-analysis of intervention effects across case experiments. RESULTS: Stimulus-specific training was successful for trained texture and proprioceptive discriminations, but it failed to show spontaneous transfer to related untrained stimuli in the same modality in seven of eight experiments in which this was possible. In contrast, intramodality transfer was obtained with stimulus-generalization training in four of five experiments that investigated stimulus-generalization training of texture discrimination. Findings were confirmed by meta-analysis. CONCLUSIONS: Our findings demonstrate generalization of training within a somatosensory modality poststroke, provided that a program designed to enhance transfer is used. This has implications for the design of efficient rehabilitation programs. 相似文献
68.
69.
Comparison of Microcomputed Tomographic and Microradiographic Measurements of Cortical Bone Porosity
Cortical bone is perforated by a network of canals that have a significant impact upon its material properties. Microcomputed tomography offers the possibility of noninvasively visualizing and quantifying cortical pores in both two and three dimensions. Establishing how two-dimensional (2D) microcomputed tomographic (CT) analysis compares with conventional methods for analyzing cortical porosity is an important prerequisite for the wider adoption of this technique and the development of three-dimensional (3D) analysis. Therefore, we compared porosity-related parameters from 2D microcomputed tomographic images with those from matching microradiographic sections. Samples from five human femora were scanned at a 10-m resolution and then sequentially sectioned and microradiographed. An average of eight image pairs were produced from each femur (total, n = 41). The repeatability and comparability of the two techniques was assessed for three parameters; cortical porosity (%), mean pore area (m2), and pore density (pores/mm2). For repeatability, no significant difference (P > 0.05) was found between the two methods for cortical porosity and mean pore area; however, pore density differed significantly (P < 0.001). For comparability, the bias (± error) between the methods was found to be 0.51% (±0.31%) for cortical porosity and –155 m2 (±293 m2) for mean pore area. The bias for pore density was dependent upon measurement size with microcomputed tomographic images having 14% (±9.3%) fewer pores per millimeter squared. The qualitative and quantitative similarities between the two techniques demonstrated the utility of 2D microcomputed tomographic for cortical porosity analysis. However, the relatively poor results for pore density revealed that a higher resolution (<10 m) is needed to consistently visualize all cortical pores in human bone. 相似文献
70.
Immunologic approaches to the treatment of prostate cancer. 总被引:8,自引:0,他引:8
D T Harris G R Matyas L G Gomella E Talor M D Winship L E Spitler M J Mastrangelo 《Seminars in oncology》1999,26(4):439-447
The presence of several organ-specific molecules that could serve as immunogens or targets of an immune attack, the nonessential nature of the prostate gland, the substantial failure rate after treatment of the primary tumor, and the lack of effective chemotherapy for metastatic disease make prostate cancer an ideal candidate for immunotherapy. This report reviews the current status of two novel approaches to the treatment of prostate cancer. The first is an effort to induce antitumor immunity by enriching the cytokine environment within the primary cancer by intraprostatic injection of Leukocyte Interleukin (Cel-Sci Corp, Vienna, VA), a mixture of natural cytokines that includes interleukin-1 beta (IL-1beta), IL-2, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon gamma (IFN-gamma), and tumor necrosis factor alpha (TNF-alpha). The second approach uses OncoVax-P (Jenner Biotherapies, Inc, San Ramon, CA), a vaccine consisting of liposome-encapsulated recombinant prostate-specific antigen (PSA) and lipid A. When administered as an emulsion or in association with bacillus Calmette-Guérin (BCG)/cyclophosphamide or GM-CSF with or without IL-2/cyclophosphamide, immunologic tolerance is broken as evidenced by the generation of humoral and cellular immunity. Both of these approaches have been shown to be feasible and safe, and are now being tested in patients with less advanced disease to determine if manipulation of the immune system can favorably influence clinical outcome. 相似文献