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51.
Guang-Xian Zhang Cun-Gen Ma Bao-Guo Xiao Moiz Bakhiet Hans Link Tomas Olsson 《European journal of immunology》1995,25(5):1191-1198
To understand the role of CD8+ T cells in experimental autoimmune myasthenia gravis (EAMG), CD8+ T cells were depleted by injecting a monoclonal anti-rat CD8 antibody (OX8) into Lewis rats immunized with Torpedo acetylcholine receptor (AChR) in complete Freund's adjuvant (CFA). CD8-depleted EAMG rats showed strikingly less muscle weakness and lower anti-AChR IgG antibody levels compared to Hy2-15-injected control EAMG rats. Moreover, the numbers of AChR-specific IgG antibody-secreting cells, AChR-reactive interferony-γ-secreting T helper type 1-like cells and lymphocyte proliferation to AChR were lower in the CD8-depleted group than in control EAMG rats. These differences were significant among mononuclear cells from inguinal and popliteal lymph nodes, mesenteric lymph nodes and spleen, but not from thymus when examined 3, 5 and 7 weeks post-immunization. We suggest that CD8+ T cells are involved in the induction and persistance of EAMG by directly or indirectly affecting AChR-reactive T cells and anti-AChR IgG antibody-secreting cells. 相似文献
52.
Mikko?PS?AresEmail author Maria?Stollenwerk Anneli?Olsson Bengt?Kallin Stefan?Jovinge Jan?Nilsson 《BMC immunology》2002,3(1):13
Background
Inflammation and immune responses are considered to be very important in the pathogenesis of atherosclerosis. Lipid accumulation in macrophages of the arterial intima is a characteristic feature of atherosclerosis which can influence the inflammatory potential of macrophages. We studied the effects of lipid loading on the regulation of TNF expression in human monocyte-derived macrophages. 相似文献53.
54.
Cardiovascular purinoceptors 总被引:45,自引:0,他引:45
55.
Polyethylene tubings, 2-mm inner diameter and the length of 1 m, untreated or furnished with a covalently bonded heparin surface layer, were inserted as arteriovenous shunts bilaterally in dogs. By compressing the middle part, the initial blood flow was adjusted to 10 or 40 mL/min. The thrombogenicity of the tubings was assessed by the patency of the shunts and by assaying the generation of fibrinopeptide A (FPA) in arterial blood and in blood after its passage through the shunts. In untreated shunts clotting rapidly occurred preceded by high FPA generation in blood passing through the shunts. The blood flow in heparinized shunts remained unchanged throughout the test period. At the low flow rate a certain degree of FPA generation in the shunts occurred. At the high flow rate no changes in FPA levels occurred. The function of the heparin surface is thus flow rate dependent. Systematic heparinization and subsequent neutralization with protamine or administration of protamine alone did not interfere with the function of the heparin surface. 相似文献
56.
Y chromosome deletions in azoospermic and severely oligozoospermic men undergoing intracytoplasmic sperm injection after testicular sperm extraction 总被引:11,自引:16,他引:11
Silber SJ; Alagappan R; Brown LG; Page DC 《Human reproduction (Oxford, England)》1998,13(12):3332-3337
Y chromosome deletions encompassing the AZFc region have been reported in
13% of azoospermic men and 7% of severely oligozoospermic men. We examined
the impact of these Y deletions on the severity of testicular defects in 51
azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after
testicular sperm extraction (TESE) and 30 men with severe oligozoospermia
undergoing ICSI after ejaculation of spermatozoa. In addition, five
azoospermic patients shown previously to have Y chromosome deletions
underwent histological evaluation of their previously obtained testis
biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not
Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent
TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y
chromosome AZFc region. Of these 10, five had spermatozoa retrievable from
the testis, and in two cases the wives became pregnant. Of the 41
azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa
retrievable from the testis, and in 12 cases (29%) the wives became
pregnant. Four of 30 (13%) severely oligozoospermic patients were found to
be deleted for AZFc and in three (75%) of these pregnancy was achieved. The
other 26 severely oligozoospermic couples who had no AZFc deletions
underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The
embryo implantation rate was not significantly different for azoospermic
(22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the
total of 19 infertile men who had Y chromosome deletions, 14 had deletions
within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14
had some spermatozoa (however few in number) in the ejaculate or testis.
Five of the Y-deleted men had deletions that extended more proximally on
the Y chromosome, and in none of these could any spermatozoa be observed in
either ejaculate or testis. These results support the concept that, in
azoospermic or oligozoospermic men with Y chromosome deletions limited to
intervals 6D-6F (AZFc), there are generally very small numbers of
testicular or ejaculated spermatozoa. Larger Y deletions, including and
extending beyond the AZFc region and encompassing more Y genes, tend to be
associated with a total absence of testicular spermatozoa. In those cases
where spermatozoa were retrieved, the presence of Y deletions had no
obvious impact on fertilization or pregnancy rate.
相似文献
57.
Kronqvist M Johansson E Whitley P Olsson S Gafvelin G Scheynius A van Hage-Hamsten M 《International archives of allergy and immunology》2001,126(1):41-49
BACKGROUND: The major allergen of the dust mite Lepidoglyphus destructor, Lep d 2, has been produced as a recombinant allergen (rLep d 2) with IgE reactivity both in vivo and in vitro. A modified form of rLep d 2 (rLep d 2.6Cys) obtained by site-directed mutagenesis has been shown to have a reduced IgE reactivity in vitro. In this study we have compared the ability of rLep d 2 and rLep d 2.6Cys to elicit positive skin prick tests and cellular responses among L. destructor-sensitized subjects. METHODS: Seventeen subjects were skin prick-tested with rLep d 2, rLep d 2.6Cys, histamine and negative controls and 17-20 h later skin biopsy specimens were taken from the skin prick-tested sites. The biopsy specimens were stained immunohistochemically for EG2+, CD3+, CD1a+, mast cell tryptase+, and IgE+ cells. Dermal cell infiltrates were judged in hematoxylin and eosin staining. Total IgE and allergen-specific IgE were determined by CAP-RAST. RESULTS: Compared to rLep d 2, rLep d 2.6Cys induced significantly smaller and fewer skin prick test reactions (p < 0.001) and dermal cell infiltrates (p < 0.05). Further, rLep d 2.6Cys induced fewer EG2+ cells (p < 0.001) but more tryptase+ cells (p < 0.05) than rLep d 2. A positive RAST to rLep d 2 was obtained for 88.2% of the subjects, while only 35.2% displayed a positive RAST to rLep d 2.6Cys. CONCLUSION: This study demonstrates that rLep d 2.6Cys is less able to evoke IgE-mediated reactions and cellular responses, as measured both in skin and in serum, than rLep d 2. In the future this hypoallergenic derivative may be a promising candidate molecule for immunotherapy of L. destructor-allergic patients. 相似文献
58.
A Kierkegaard L Norgren C G Olsson J Castenfors G Persson S Persson 《Acta medica Scandinavica》1987,222(5):409-414
In order to detect deep vein thrombosis (DVT), 101 patients with acute medical or infectious disorders were examined with the 125I-fibrinogen uptake test. All patients were bedridden on admission and were scanned daily from the second to the eighth day. Thirteen patients developed a positive fibrinogen uptake test. Thus, if a positive test is interpreted as DVT, the incidence of DVT was 13% in our bedridden patients. Of the patients admitted because of heart disease or pneumonia 20% had DVT, but only 4% of those admitted with other diagnoses. Other clinical "risk factors" studied, could not identify patients who developed DVT. 相似文献
59.
G Fredrikson S Nilsson H Olsson L Bj?rck B Akerstr?m P Belfrage 《Journal of immunological methods》1987,97(1):65-70
The newly described immunoglobulin G-binding streptococcal surface protein, protein G, was used to prepare and characterize rabbit antibodies. The antibodies were directed against rat hormone-sensitive lipase, the rate-limiting enzyme in the hydrolysis of the triacylglycerols stored in adipose tissue. Antiserum was obtained after two injections with 20 micrograms enzyme protein, and the immunoglobulin fraction was obtained using a protein G-based solid-phase radioimmunoassay. The hydrolysis of acylglycerols by the enzyme was inhibited by the antibodies, and the enzyme could be efficiently removed from a solution using the antibodies and heat-killed streptococci expressing surface protein G. By Western blot and detection with 125I-protein G, the antibodies were found to selectively bind to hormone-sensitive lipase and to a smaller extent to two minor contaminants, possibly proteolytic fragments of the lipase. The amount of 125I-labelled protein G bound to the lipase on the blot was quantitatively related to the amount of enzyme protein down to the detection limit 10 ng. 相似文献
60.
R. S. Johansson M. Trulsson K. Å. Olsson K. -G. Westberg 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1988,72(1):204-208
Summary The feasibility of adopting the microneurography technique (Vallbo and Hagbarth 1968) as a tool to investigate the mechanoreceptive innervation of peri- and intra-oral tissues was explored. Multi-unit activity and impulses in single nerve fibers were recorded from the infraorbital nerve in healthy volunteers. The innervation territories of individual nerve fascicles were mapped. These varied considerably but most fascicle fields comprised the corner of the mouth. Twenty-four single mechanoreceptive units were recorded. Eighteen innervated the skin of the face, and six innervated the mucous membranes of the lips or cheeks. A majority of the mechanoreceptive afferent units were slowly adapting with small and well defined receptive fields. It is suggested that the various slowly adapting responses may originate from two different types of afferent units. No afferents showed response properties similar to typical Pacinian-corpuscle afferents. 相似文献