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2.
Grabau DA Rank F Friis E 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2005,113(1):7-12
The study presents the results from intraoperative frozen section assessment of axillary sentinel lymph nodes (SLNs) in breast cancer. Routine histological frozen sections from one level were used, two sections stained with haematoxylin and eosin. Immunohistochemistry for cytokeratins was applied to the permanent SLN paraffin sections only. Axillary dissection was performed on all SLN-positive cases regardless of the size of the metastatic deposits. With a detection rate of 83%, 272 patients entered the study over a period of 46 months. A total of 61 cases were SLN positive by frozen section analysis. The paraffin sections gave an additional 23 SLN-positive cases. The false-negative rate for frozen sections was then 27% (23/84). Micrometastases were found in 28 of 84 cases, and macrometastases in 56. The false-negative rate of frozen sections for micrometastases was 71% (20/28), and for macrometastases 5% (3/56). A total of 73% (61/84) of the patients underwent axillary surgery as a one-step procedure. 相似文献
3.
Humoral immune response to chlamydial genital infection of mice with the agent of mouse pneumonitis. 总被引:5,自引:11,他引:5
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The objective of this study was to characterize the humoral immune response to chlamydial genital infection of mice with the mouse pneumonitis agent (MoPn). With an enzyme-linked immunoabsorbent assay, immunoglobulin G antibodies to MoPn were first detected in plasma by day 14. Peak plasma antibody concentrations were reached by day 49, and this response did not decline significantly throughout the 300-day monitoring period. Immunoglobulin A against MoPn could first be detected in pooled vaginal washes by day 21 after infection and had reached peak concentrations by day 28, but anti-MoPn immunoglobulin G was not consistently present in secretions. The antibody response in secretions had declined slightly by day 300. Immunoblot analysis revealed that the early phase of the plasma antibody response to MoPn as a result of genital infection was against lipopolysaccharide, the major outer membrane protein, and a 62-kilodalton (kDa) protein. In secretions, early-phase immunoglobulin A antibodies were directed to the major outer membrane protein and lipopolysaccharide. Late reactions to 15-, 22-, and 83-kDa proteins in plasma were noted. Late reactions to the 62-kDa protein in secretions were also noted. The cause of these late responses remains unexplained. When mice were challenged intravaginally with MoPn at 50-day intervals after the primary infection, it was found that mice inoculated on day 100 or after were susceptible to reinfection. Susceptibility could not be related to a decline in the antibody concentration in plasma or secretions or in the antibody response to specific components of MoPn as measured by immunoblot analysis. 相似文献
4.
Initial route of antigen administration alters the T-cell cytokine profile produced in response to the mouse pneumonitis biovar of Chlamydia trachomatis following genital infection.
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A Th1-type response develops following vaginal infection with the mouse pneumonitis biovar of Chlamydia trachomatis (MoPn). Since the type of response, i.e., Th1 versus Th2, can be influenced by factors present during T-cell activation, we examined the effects of different routes of MoPn administration on the cytokine profile and resistance against infection following a MoPn vaginal challenge. A dominant Th1-type cytokine profile developed in mice given live MoPn via the intranasal, oral, and vaginal routes with ratios of gamma interferon-secreting cells to interleukin 4-secreting cells greater than 10. In contrast, mice injected subcutaneously produced a Th2-type profile with a gamma interferon/interleukin 4 ratio of only 0.7. These mice also had significantly higher anti-MoPn immunoglobulin G1 serum titers, confirming a Th2-type cytokine profile. Exposure of mice to live MoPn, by any route prior to vaginal challenge, resulted in a shortened course of infection. However, the subcutaneous group resolved the vaginal infection more slowly, with 60% (6 of 10 mice) of the mice still isolation positive 12 days after challenge compared with only 20% of mice given live MoPn by other routes. Administration of UV-inactivated MoPn did not provide protection against a vaginal challenge. The decreased ability to clear infection was not associated with a shift in the cytokine profile, since intranasal and oral administration of UV-inactivated MoPn resulted in a predominant Th1-type response. Taken together, these data indicate that the initial route of MoPn administration can direct the type of response produced after a local MoPn infection and thus influence the ability of the immune response to protect against subsequent infection. 相似文献
5.
One- to three-day-old guinea pigs were inoculated intranasally with the chlamydial agent of guinea pig inclusion conjunctivitis. Physical signs of infection included a marked increase in respiration rate on days 5 to 10 of infection and radiographic evidence of pneumonia on day 6. When animals were killed at various times after infection and lung tissue was examined by histopathology, evidence of pneumonia was found beginning on day 4 and lasting as long as day 12, with maximal pathological changes on days 6 to 8. The pneumonia was generally unilateral and consisted of an acute inflammatory component in the bronchioles with granulocytes in both the lumen and the wall of the bronchioles and an interstitial and intra-alveolar mononuclear infiltrate in the parenchyma of the lung. Chlamydial antigen was detected in the bronchial epithelial cells by immunoperoxidase staining, and the guinea pig inclusion conjunctivitis organism was isolated from lung tissue on days 6 to 9. No other significant bacteria were isolated from lung tissue or seen on gram stains of lung sections. Both immunoglobulin M and immunoglobulin G serum antibodies to the guinea pig inclusion conjunctivitis agent were detected as early as day 8 and reached peak levels on day 12. The infection was apparently self-limiting. This model presents the opportunity to investigate pathophysiological and immunological aspects of chlamydial respiratory infections in a neonatal animal. 相似文献
6.
The lipid A immunity system. I. Induction of heterophile antibodies by enterobacterial lipopolysaccharides and their lipid A component 总被引:3,自引:0,他引:3
Mice were immunized either with lipopolysaccharides (LPS) or with the respective lipid A components. After four days an increase in the number of direct plaque-forming cells with complement-dependent antibody against sheep red cells was seen. Cross-reactions were observed with red cells of cattle, goats, horses and rabbits. All LPS investigated, of Shigella, Escherichia coli, and S and R form Salmonella, as well as the lipid A component evoked this immune response. We therefore conclude that all enterobacterial LPS induce an antibody which cross-reacts with SRC and that the lipid A component is responsible for this reaction. Evidence is presented that these effects, such as toxicity, fever, pyrogen tolerance, leucopenia/leucocytosis, nonspecific immunity, and tumor inhibition are mediated by lipid A-induced antibodies. 相似文献
7.
A histopathologic study of gastric and small intestinal graft-versus-host disease following allogeneic bone marrow transplantation 总被引:10,自引:0,他引:10
D C Snover S A Weisdorf G M Vercellotti B Rank S Hutton P McGlave 《Human pathology》1985,16(4):387-392
Twenty-two stomach and 14 small intestinal biopsy specimens from 24 allogeneic bone marrow transplant recipients were reviewed to evaluate the histopathologic changes of graft-versus-host disease (GVHD) in these organs. Associations between these results and clinical symptoms and other biopsy results were sought. In both organs, single epithelial cell necrosis was found to correlate with GVHD. Gastric GVHD was diagnosed in eight patients and small intestinal GVHD in four. Gastric GVHD was characterized by nausea, vomiting, and upper abdominal pain without diarrhea (the latter being present in only two patients), while all four of the patients with small intestinal GVHD had upper gastrointestinal symptoms and diarrhea. These symptoms correlated with concurrent rectal biopsy findings; pathologic alterations were seen in only one of six specimens from patients with gastric GVHD but in three of four with small intestinal GVHD. These findings suggest that stomach biopsy may be necessary to diagnose GVHD in patients with upper gastrointestinal symptoms but no diarrhea and normal rectal biopsy specimens. Diagnostic problems may arise in the early posttransplantation period, when the effects of cytoreductive therapy may simulate GVHD, and in patients with gastrointestinal cytomegalovirus infection, which may also produce changes identical to those of GVHD. 相似文献
8.
Role of cell-mediated immunity in the resolution of secondary chlamydial genital infection in guinea pigs infected with the agent of guinea pig inclusion conjunctivitis. 总被引:4,自引:12,他引:4
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Guinea pigs which have recovered from a genital infection with the agent of guinea pig inclusion conjunctivitis demonstrate strong immunity to reinfection for a short period of time but then become susceptible to reinfection. The secondary infection is markedly shortened in duration and decreased in intensity. Previous studies have indicated an important role for humoral immunity in resistance to and in recovery from reinfection. However, the contribution of cell-mediated immunity to immunity toward or recovery from a secondary infection is not clear. Guinea pigs were infected in the genital tract with guinea pig inclusion conjunctivitis and were challenged at either 30 or 75 days after the primary infection. Prior to challenge, one group of animals were injected with rabbit anti-guinea pig thymocyte serum (ATS) while control groups received either normal rabbit serum or no treatment. Treatment was continued daily for the course of the experiment. On day 30, ATS-treated guinea pigs had a slightly higher rate of reinfection, and generally the infection persisted longer than in controls. On day 75, all animals became reinfected upon challenge, but control animals resolved their infections in 3 to 9 days. In contrast, most ATS-treated animals remained infected throughout the course of the experiment. Although the animals became reinfected, the levels of chlamydiae were much lower than those observed during the primary infection. ATS treatment abrogated T-cell responses, but serum and secretory antibody responses remained normal. Histopathological examination revealed some decrease in mononuclear infiltration of endocervical and uterine tissues in ATS-treated animals. These data indicate that previously infected guinea pigs require both cell-mediated immunity and humoral immunity for resolution of a challenge infection. 相似文献
9.
Does Inhibition of Tumor Necrosis Factor Alpha Affect Chlamydial Genital Tract Infection in Mice and Guinea Pigs? 总被引:4,自引:0,他引:4
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The role of tumor necrosis factor alpha (TNF-alpha) in host defense against chlamydial infection remains unclear. In order to further evaluate the relevance of TNF-alpha to host resistance in chlamydial genital tract infection, we examined the effect of local inhibition of the TNF-alpha response in normal C57 mice and in interferon gamma gene-deficient C57 mice infected intravaginally with the mouse pneumonitis agent of Chlamydia trachomatis. Since the guinea pig model of female genital tract infection more closely approximates the human in terms of ascending infection and development of pathology, we also examined the effect of local inhibition of the TNF-alpha response in guinea pigs infected intravaginally with the guinea pig strain of Chlamydia psittaci. We successfully blocked the early TNF-alpha response in the respective animal models. This blockade had no effect on the numbers of organisms isolated from the genital tract during the time of TNF-alpha inhibition in mice or guinea pigs. Analysis of interleukin-1beta, macrophage inflammatory protein-2, and granulocyte macrophage-colony stimulating factor in the mouse model revealed that blockade of the TNF-alpha response did not alter the release of these proinflammatory proteins. Yet, in TNF-alpha-depleted mice, increased numbers of neutrophils were detected in the genital tract, and, in TNF-alpha-depleted guinea pigs, increased numbers of neutrophils as well as infiltrating lymphocytes were seen in the endocervix. Blockade of TNF-alpha does not affect the level of infection in mice or guinea pigs, but it may decrease TNF-alpha-induced apoptosis of infiltrating inflammatory cells. 相似文献
10.
Pathogenesis of endometritis and salpingitis in a guinea pig model of chlamydial genital infection.
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The development of tubal obstruction and subsequent infertility is a major sequelum of upper genital tract infection with Chlamydia trachomatis; however, little is known about the pathogenesis of the infection. In this investigation, the authors present a detailed study of the progression of ascending chlamydial infection in female guinea pigs resulting from intravaginal inoculation of the Chlamydia psittaci agent of guinea pig inclusion conjunctivitis (GPIC). Isolation of chlamydiae from different tissues of the genital tract revealed definitive evidence for ascending infection that was not dose-related. By 7 days after infection, GPIC was isolated from the endometrium and oviducts of 78% of the animals. Pathologic changes analogous to those seen in human chlamydial disease, including polymorphonuclear, mononuclear, and plasma cell infiltration, were seen in the endometrium and oviducts, although not all isolation positive animals developed overt tubal disease. Long-term fibrosis, often in combination with hydrosalpinx, was noted in the mesosalpingeal tissue in 20% of the animals. Thus, the guinea pig:GPIC system represents a model for ascending chlamydial infection resulting from vaginal inoculation of normal guinea pigs that closely approximates the disease as seen in humans and can be used to study the pathogenesis of chlamydial genital infection. 相似文献