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11.
C3H/HeJ mice received B10.BR skin grafts following portal or lateral tail vein infusion of irradiated B10.BR spleen cells. Thereafter mice were injected with anti-alpha beta or anti-gamma delta T-cell receptor (TCR) monoclonal antibody (mAb). Anti-gamma delta TCR mAb abolished the increased graft survival afforded by portal venous (p.v.) immunization, and reversed the bias towards expression of mRNA for type-2 cytokines [interleukin-4 (IL-4), IL-10] seen in lymphoid tissue of p.v.-immunized mice. When gamma delta TCR+ and alpha beta TCR+ cells were isolated from the intestinal epithelial compartment (IEL), liver or Peyer's Patch (PP) of p.v.-immunized mice, the gamma delta TCR+ cells were found to be enriched in cells producing type-2 cytokines on rechallenge with irradiated B10.BR cells in vitro. gamma delta TCR+ cells from p.v.-immunized mice were further expanded in vitro with anti-CD3 and cytokines (combined IL-2 and IL-4). Following expansion these cells were capable of adoptively transferring increased B10.BR skin graft survival to naive mice, and continued to show a bias in type-2 cytokine synthesis after allostimulation in vitro. When gamma delta TCR chain expression was assessed in cells taken from p.v.-immunized mice, or in cells expanded in culture, our data suggest that p.v. immunization leads to oligoclonal, not polyclonal, expansion of those gamma delta TCR+ cells involved in inhibition of graft rejection. 相似文献
12.
Hussey SM Gander R Southern P Hoang MP 《Archives of pathology & laboratory medicine》2005,129(6):794-797
Primary subcutaneous phaeohyphomycosis can rarely be caused by Cladophialophora bantiana, and we present the histologic and culture findings of such a case. A 32-year-old African American woman with systemic lupus erythematosus presented with a 2-year history of multiple, recurrent, tender, and ulcerated skin nodules with purulent drainage on her upper back. Histologic sections of the excision demonstrated features of phaeohyphomycosis. Culture findings were characteristic of C bantiana. Of interest, at age 10 she had sustained traumatic implantation of wood splinters into this area during a tornado, yet clinical symptoms of a subcutaneous infection did not manifest until she developed lupus erythematosus at age 27. Our case highlights the role of trauma and immunosuppression in the pathogenesis of subcutaneous phaeohyphomycosis. 相似文献
13.
Warner EA Deyoung DZ Hoang TX Franchini BT Westerlund U Havton LA 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,161(4):527-531
GAP-43 is normally produced by neurons during developmental growth and axonal regeneration, but it is also expressed in specific regions of the normal adult nervous system. We studied the protein expression of GAP-43 within the conus medullaris portion of the spinal cord in adult male rats. Immunohistochemistry for choline acetyltransferase (ChAT) was first performed to identify specific efferent autonomic and motor nuclei in lumbosacral segments of the spinal cord. Adjacent sections were then processed for GAP-43 immunoreactivity (IR). We show GAP-43 IR in the superficial portion of the dorsal horn, the intermediolateral nucleus, and the dorsal commissural tract. We also demonstrate a differential distribution of GAP-43 IR between different motor nuclei of the conus medullaris. Using densitometry, the most prominent GAP-43 IR was detected in the dorsolateral and dorsomedial motor nuclei, which represent the human Onufs nucleus homologue. Confocal microscopy of double immunofluorescent labeling for ChAT and GAP-43 demonstrate GAP-43 IR in the neuropil of the autonomic and motor nuclei, and many of the GAP-43 IR arbors are in close apposition with the efferent cholinergic neurons. We note that the efferent neurons of both the autonomic and somatic nuclei, which are ultimately responsible for the integrated normal control of the lower urinary tract, bowel and sexual functions, are heavily innervated by GAP-43 enriched projections. We speculate that these functionally related neurons retain a physiological GAP-43-associated synaptic plasticity throughout adult life. 相似文献
14.
Naive or preimmunized (to B10.BR or BALB.k) C3H/HeJ mice received skin grafts from multiple minor histoincompatible B10.BR or BALB.k mice following antigen-specific portal venous (p.v.) pretransplant transfusion, a protocol known to produce prolongation of graft survival in naive animals. In addition, groups of mice received intravenous (i.v.) infusion following transplantation with a mixture of monoclonal antibodies (mAb) to vascular adhesion molecule-1L: very late activation antigen-4 (VCAM-1:VLA-4) or intracellular adhesion molecule-1:lymphocyte function-associated antigen-3 (ICAM-1:LFA-1). Cells were harvested from different tissues of the grafted mice at various times post grafting. RNA was extracted and analysed, using polymerase chain reaction, for expression of different cytokines potentially involved in the regulation of graft rejection [interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumour necrosis factor-alpha, interferon-gamma and transforming growth factor-beta]. In addition, using limiting dilution analysis, we investigated the frequency of allo-specific and third-party reactive cells producing IL-2 and IL-4 in vitro in different tissues of grafted mice following these treatments. The mAb treatment protocol which produced optimum increases in graft survival in naive versus immune mice was different, with anti-LFA-1:ICAM-1 superior for naive mice compared with anti-VLA-4:VCAM-1, and vice versa for immune animals. However, in each case, increased survival was associated with increases local to the graft in the frequency of occurrence of antigen-specific type-2 cytokine-producing cells. 相似文献
15.
Hoang MP Rogers BB Dawson DB Scheuermann RH 《American journal of clinical pathology》1999,111(5):655-659
Human herpesviruses are associated with morbidity and mortality in persons with compromised immune systems, including patients infected with human immunodeficiency virus (HIV). To investigate the basis for this association, the levels of all 8 human herpesviruses (herpes simplex virus, types 1 and 2, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, and human herpesvirus 6, human herpesvirus 7, and human herpesvirus 8) were measured with the quantitative polymerase chain reaction (PCR). Viral DNA was measured in the whole blood of 20 HIV-infected patients and compared with levels in 20 healthy blood donors. There was no significant difference in the frequency of virus detection of the 8 human herpesviruses between HIV-infected patients and healthy adults. These results indicate that HIV infection is not associated with a general increase in the circulating levels of human herpesviruses, and suggest that quantitative PCR analysis is superior to qualitative PCR analysis for detection of clinically relevant disease in HIV-infected patients. 相似文献
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18.
A colorless, parallelepiped crystal of methyl (2R,3S)-N-benzoyl-3-phenylisoserinate belonging to the space group P2l with a = 5.414(4), b = 7.813(1), c = 17.802(7) , = 90.87(4)°, Z = 2, V = 752.9 3, D
calc = 1.32 g cm–3, and µcalc = 1.02 cm–1 was selected and the structure solved using direct methods. Refinement led to a final R = 0.079 for 819 [F
o 5(Fo)] reflections. Intermolecular hydrogen-bonding interactions are prevalent in the crystal lattice of this compound. 相似文献
19.
Thi Thanh Ha Nguyen Thuy Long Hoang Thi Hoi Nguyen The Tram Nguyen Lundström G Olsson-Liljequist B Kallings I 《International journal of antimicrobial agents》1991,1(2-3):121-126
The in vitro antimicrobial susceptibilities of 675 common enteropathogenic isolates from faecal specimens of patients with diarrhea (E. coli, Shigella, Salmonella and V. cholerae), and 568 E. coli isolates from faecal flora of healthy persons, which were collected as part of a National antibiotic resistance surveillance in Vietnam, were determined. The agar dilution method was used for the following nine antibiotics: ampicillin, doxycycline, chloramphenicol, gentamicin, nalidixic acid, kanamycin, trimethoprim, trimethoprim in combination with sulfamethoxazole (1/20), and sulfisomidin. Gentamicin was the most active of the antibiotics tested against all bacterial species with MICs in the range 0.125-4 mg/l. All strains were susceptible to nalidixic acid (0.125-8 mg/l) and more than 90% were susceptible to kanamycin. Among E. coli and Shigella isolates from patients the frequencies of resistance to commonly used antibiotics were high: ampicillin 73% and 84%, doxycycline 83% and 94%, chloramphenicol 71% and 91%, sulfisomidin 82% and 92%, respectively. Resistance to trimethoprin, as well as to the combination with sulfamethoxazole was found in 21% and 23%, respectively. The frequencies of multiple resistance (resistance to three or more antibiotics) were also high (77% and 89%, respectively). Less than 10% of Salmonellae and V. cholerae isolates were resistant to ampicillin, sulfisomidin or trimethoprim. Among E. coli from healthy people the frequencies of resistance were lower than in isolates from patients: ampicillin 23%, doxycycline 40%, chloramphenicol 21% and sulfisomidin 34%. However, the same patterns of multiple resistance were found in both groups. 相似文献
20.