Histopathologic changes during chronic small bowel allograft rejection.
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Publications and source records attributed to F Offner.
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OBJECTIVES: The EORTC Invasive Fungal Infections Cooperative Group (IFICG) conducted a prospective survey by questionnaire of all cases of invasive aspergillosis (IA) in cancer patients to ascertain current diagnostic and therapeutic approaches. METHODS: All members of the IFICG were asked prospectively to complete a detailed questionnaire for each IA case identified in their institution over a 12-month period. RESULTS: One hundred and thirty questionnaires were returned. All cases were independently evaluated (DWD & JC) and 123 were eligible. Cases came from 20 hospitals in eight countries and the number of cases per institution varied from 1-21. Acute myeloid leukaemia (AML) (60, 49%), acute lymphoblastic leukaemia (ALL) (21, 17%) and lymphoma (11, 9%) were the most frequent underlying diseases, and 16 (12%) patients had received an allogeneic bone marrow transplant. Pulmonary involvement was present in 87%, infection of sinuses/nose in 16% and brain in 8%. The chest radiograph was initially normal in 9% of those with primary pulmonary disease. The diagnosis was confirmed in 50%, probable in 31% and possible in 19%. The evidence for IA was on the basis of clinical and radiological features alone in 28%, with culture or histology in another 31% and 9%, respectively, and with both culture and histology in 29%. In three (2%) patients with diagnosis was based on culture or histology alone. Treatment was given to 120 patients (98%)-amphotericin B 75%, lipid-associated amphotericin B 36%, itraconazole 40%, flucytosine 12%, growth factors 33%, lobectomy 5%. At 3 months after diagnosis or first suspicion of IA, 44 (36%) patients were alive and 79 (64%) dead. Outcome was best in those with AML (30% death and 46% with a complete antifungal response or cure). Growth factors (mostly granulocyte colony stimulating factor) appeared not to influence outcome (P = 0.99). CONCLUSION: IA remains a considerable diagnostic and therapeutic challenge. No single diagnostic procedure was universally successful and a multifaceted approach including surgery is necessary. There was no discernable difference in outcome between initial therapy with amphotericin B, itraconazole or lipid-associated amphotericin B, although numbers are limited and the study was retrospective.
A retrospective analysis of 48 patients with documented or probable invasive aspergillosis (IA) prior to bone marrow transplantation (BMT) was conducted in 16 centers. Treatment of primary IA was medical in all 48 patients and surgical in 20; clinicoradiological resolution of IA occurred in 30 of 48 patients. Pretransplantation risk factors for relapse IA, total mortality, and IA-related mortality were analyzed by multivariate logistic regression with the following dichotomous risk factors: surgery as part of the initial treatment, resolution of IA by the time of BMT, donor type, conditioning regiment, total-body irradiation, T cell depletion, immunosuppressive therapy, type of antifungal prophylaxis, and growth factor prophylaxis. Conditioning with busulfan/cyclophosphamide was associated with a beneficial outcome for total survival and reduced IA-related mortality. Posttransplantation risk factors such as the development of graft-vs.-host disease (GVHD), therapy for GVHD, and the duration of neutropenia did not have a significant effect on relapse IA, IA-related mortality, or total mortality. The overall incidence of relapse IA was lower than expected (33% [16 of 48 patients]), but the mortality rate among relapsed patients was 88% (14 of 16). Patients receiving prophylaxis with absorbable or intravenous antifungals had less relapses of IA than did those not receiving prophylaxis (12 of 41 vs. four of seven, respectively). This finding reflects the need for better prophylaxis and new antifungal treatments for patients undergoing BMT who have a history of IA.
Metastasis is a complicated multi-step process involving interactions between tumour cells, the extracellular matrix and the vessel walls. Experimental observations suggest that leucocyte migration and function could be a suitable model in order to understand tumour cell dissemination. In the present report we show and quantify the production of free radicals by human malignant melanoma cells (St-ml12) by means of a spectrophotometrical method, using an enzyme immunoassay reader. Endothelial cells and activated polymorphonuclear leucocytes were used as controls. Melanoma cells without stimulants produced large amounts of superoxide anion at an increasing rate in relation to time, which could be inhibited by superoxide dismutase. Production of hydrogen peroxide was minimal. The endothelial cells produced a negligible amount, in contrast to the activated polymorphonuclear leucocytes, which released large quantities of both free radicals. A rapid assay to analyse the production of free radicals by tumour cells is presented here. Using this, we demonstrated that melanoma cells produce superoxide anions, supporting previous observations which implicate superoxide anion in the mechanism of metastasis.
Interleukin-7 (IL-7) is a non redundant cytokine in thymic T-cell development. It binds to a dimeric receptor consisting of a specific IL-7Ralpha and a gamma-common subunit that it shares with the receptors for IL-2, 4, 9, 13 and 15. IL-7 is critical for early T-cell development but it also acts on immature B-cells and mature T-cells, and leads to secondary cytokine release. Its mechanisms of action in early T-cell development may be multiple. There is direct evidence to support a mechanistic involvement in TCR-gamma rearrangement that drives further TCR-gammadelta thymocyte commitment and maturation. There is indirect evidence for a role of IL-7 in TCR-beta rearrangement. It may however also act as a survival factor for TCR-beta rearranging thymocytes while the critical commitment selections are effected by other factors. The effects of IL-7 in fetal thymus organ culture are dose dependent, with a biphasic response: low doses of IL-7 are necessary for normal TCR-alphabeta thymocyte development but high doses block TCR-alphabeta maturation in favor of TCR-gammadelta development. A good understanding of the dose response of IL-7 in thymocyte development, mature T-cell stimulation, and of the release of secondary cytokines will be important for planning successful clinical trials with IL-7.
Diagnostic procedures in inflammatory bowel diseases (IBD) serve to secure the diagnosis and to optimize treatment. Upon initial diagnosis endoscopy up to the terminal ileum is mandatory including multiple step biopsies. When diagnostic guidelines are followed and adequate clinical information is available, IBD will be correctly classified in about 80 to 90% of cases upon first examination. In contrast endoscopic studies are only of limited value in monitoring treatment. The decision if and when to perform endoscopy during exacerbation of disease must be an individual one. When disease activity is evaluated, a distinction must be made between degree of activity as reflected by laboratory parameters and severity of illness as reflected by the clinical presentation with abdominal complaints, fistulas, abscesses, etc. Distinct activity indices are useful in clinical studies to obtain an objective evaluation of activity and severity of disease. At clinical routine visits questions should not only concern the basic illness but also ask for quality of life and psychosocial status. Only a small number of laboratory tests are needed for basic diagnosis and follow-up. A small bowel enteroclysis should always be performed upon primary diagnosis of Crohn's disease and during the course of disease when there is suspicion of small-bowel involvement. Double contrast barium enema should be limited to special indications as incomplete colonoscopy e.g. due to stenosis or suspected fistula. Sonography is the primary investigation when complications are suspected. CT is useful as an adjunct or when the afore mentioned methods do not show clear findings. NMR is the procedure of choice for detection of pararectal fistulas and abscesses. Transrectal endosonography is comparably good but limited to the experience of the investigators and by patient's tolerability.
In contrast to thymic differentiation of TCR alphabeta cells, differentiation stages of TCR gammadelta cells are largely unknown. This report shows that CD1, a known marker of immature TCR alphabeta thymocytes, was expressed on some postnatal TCR gammadelta thymocytes. Only CD1+ TCR gammadelta thymocytes expressed recombination-activating gene-1 mRNA, and they were shown to differentiate into CD1- TCR gammadelta thymocytes. Functionally, sorted CD1- TCR gammadelta thymocytes proliferated in the presence of immobilized anti-CD3 Ab plus exogenous rIL-2 or rIL-15. Interestingly, in contrast to CD1- TCR alphabeta cells, CD1- TCR gammadelta thymocytes also proliferated extensively when cultured with exogenous rIL-2 or rIL-15 alone. FACS analysis as well as reverse transcription-PCR analysis showed that only CD1- TCR gammadelta thymocytes expressed IL-2Rbeta protein and mRNA. The differential expression of maturation markers, such as CD27, CD45RO, and CD45RA, as a function of expression of CD1 was similar in TCR gammadelta and TCR alphabeta thymocytes. An important exception is the expression of CD4 and CD8. Whereas TCR alphabeta thymocytes are mainly CD4-CD8 double positive at the immature CD1+ stage and CD4 or CD8 single positive at the mature CD1- stage, CD1(bright) TCR gammadelta thymocytes all expressed CD4, but only some of them expressed CD8. Some CD1- TCR gammadelta thymocytes also expressed CD8, but were negative for CD4. Collectively, our data clearly show that CD1 is a useful marker to distinguish immature human TCR gammadelta thymocytes from functional mature gammadelta cells based on recombination-activating gene-1 expression, in vitro differentiation, and phenotypic and functional characteristics.
Hematopoietic growth factors have been used in prophylaxis and treatment of neutropenic febrile episodes. Granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) are the most common growth factors in clinical use. Both successfully shorten the duration of neutropenia following myelo-suppressive or myeloablative chemotherapy. The influence of G-CSF and GM-CSF on documented infections and mortality from infections is less obvious. There is no clear evidence that treatment with growth factors reduces the incidence of fungal infections. Since mortality is not affected, considerations of morbidity and cost effectiveness currently dominate the indication for use of growth factors. At current costs, their use is indicated in prophylaxis when the likelihood of developing neutropenic febrile episodes following chemotherapy is 40% or more.
To define structural elements involved in translocation of human cytomegalovirus (HCMV) glycoprotein B (gB) to the inner nuclear membrane (INM) compartment, mutagenized gB derivatives with deletions of the potential membrane anchor domains or of portions of the cytoplasmic tail were stably expressed in human astrocytoma cells. Subcellular localization examined by immunofluorescence and cell fractionation suggested that all gB derivatives reached the INM; however, reduced amounts were found after deletion of the extreme carboxy terminus [amino acids 856-906; gB(Del3)]. Pulse-chase analysis revealed accumulation in nuclear fractions of all gB derivatives during the chase, except for gB(Del3), which exhibited impaired nuclear retention. A carboxy-terminal nucleoplasmin-like signal localized within the respective deletion may thus be involved in nuclear transport and retention of HCMV gB. Immunoprecipitation after 32P-radiolabelling of the gB transfectants verified that the gB molecule is phosphorylated at a carboxy-terminal consensus motif for casein kinase II.
The Hermansky-Pudlak syndrome (HPS) associates oculocutaneous albinism with a haemorrhagic diathesis and the accumulation of ceroid-like material in different tissues. HPS is not an uncommon type of albinism as it was diagnosed in 13.5% (8/59) of our autosomal recessive albinos. These eight patients were evaluated ophthalmologically and haematologically. Apart from the symptoms caused by the albinism, accompanying signs vary from ecchymoses to life threatening haemorrhages and death by associated restrictive lung disease. Recognition of this syndrome by the ophthalmologist can be of major importance in this serious and eventually fatal disorder.
We characterized the relationship between severe neutropenia and risk of death in 2,276 patients after marrow transplantation to define objective and clinically relevant criteria that could be used to judge the timing and potential value of interventions designed to improve survival in patients with delayed initial engraftment. Proportional hazard models were used to estimate the relative risk of death before day 100 among patients alive on any given day with an absolute neutrophil count (ANC) less than 100/microL compared with those alive on the same day with an ANC > or = 100/microL. Between day 10 and 14, the risk ratio remained close to 1.0, indicating that the risk of death before day 100 for patients with an ANC less than 100/microL was similar to that for patients with an ANC > or = 100/microL. Between day 15, when 38% of patients had an ANC less than 100/microL, and day 26, when 3.8% of patients had an ANC less than 100/microL, the risk ratio showed an overall upward trend, indicating that patients with an ANC less than 100/microL had a higher risk of death before day 100 than those with an ANC > or = 100/microL. Thereafter, the risk ratio fluctuated between 2.01 and 5.78, indicating consistently higher risks of mortality in patients with severe neutropenia. However, allogeneic and autologous transplant recipients each had distinctive risk ratio patterns. These results could be helpful in deciding the appropriate timing for treatment given to improve graft function after marrow transplantation.
Ovarian cancer arises mostly from the ovarian surface epithelium. The aim of our study was to compare the effects of cytokines in ovarian surface epithelial (OSE) cells and in ovarian carcinoma cells. Proliferation and expression of surface antigens (CA-125 and classes I and II antigens of the major histocompatibility complex [MHC]) were measured in OSE cells obtained from 7 different patients and 7 ovarian carcinoma cell lines. Proliferation of OSE cells remained unaffected by interferon (IFN)-alpha or IFN-gamma, whereas interleukin-1 (IL-1) and tumor necrosis factor (TNF) increased cell growth. Proliferation of ovarian carcinoma cells was reduced by both types of IFN as well as TNF but was not affected by IL-1. Expression of the tumor marker CA-125 was increased by IFN-gamma in ovarian carcinoma cells but not by any other treatment. None of the cytokines affected CA-125 surface expression in OSE cells. Expression of MHC-I was augmented in OSE and in carcinoma cells by both IFNs but not by the other cytokines. Both types of cell were negative for MHC-II, but IFN-gamma induced its expression in both OSE and carcinoma cells. Significant concentrations of the cytokines evaluated here have been measured in blood and follicular fluid by several authors. The different actions of these cytokines in OSE and carcinoma cells could therefore be important in understanding the role of such molecules in the regulation of physiological and pathological processes in the ovary, such as ovulation or malignant proliferation.
Immunization with cardiac myosin induces T cell-mediated myocarditis in genetically predisposed mice and serves as a model for autoimmune heart disease. This study was undertaken to identify pathogenic epitopes on the myosin molecule. Our approach was based on the comparison of the pathogenicity between cardiac (alpha-)myosin and soleus muscle (beta-)myosin. We show that alpha-myosin is the immunodominant isoform and induces myocarditis at high severity and prevalence whereas beta-myosin induces little disease. Therefore the immunodominant epitopes of alpha-myosin must reside in regions of different amino acid sequence between alpha- and beta-myosin isoforms. Cardiac myosin peptides corresponding to these regions of difference were synthesized and tested for their ability to induce inflammatory heart disease. Three pathogenic peptides were identified. One peptide that is located in the head portion of the molecule induced severe myocarditis, whereas two others that reside in the rod portion possessed only minor pathogenicity. The identification of pathogenic epitopes on the cardiac myosin molecule will allow detailed studies on the recognition of this antigen by the immune system and might be used to downmodulate ongoing heart disease.
OBJECTIVES: Blood group antigens traditionally have been associated with a risk of developing peptic ulcer and gastric cancer. Helicobacter pylori is a bacterium associated with chronic active gastritis and ulcer disease, and its attachment to gastric mucosa was recently shown in vitro to be mediated by blood group Lewisb and H antigens. This study was designed to test the clinical relevance of this laboratory observation in patients undergoing endoscopy and gastric biopsy. METHODS: Blood group phenotypes and gastric biopsies for H. pylori and histology were determined and correlated in 384 patients undergoing upper endoscopy. Blood from healthy blood donors was tested for the same blood group antigens and used as a control group. RESULTS: The distribution of blood groups ABO, Lewis, Rhesus, and MN was similar among the patients undergoing endoscopy and a control group of 2369 healthy blood donors from the same geographic area. There was no correlation between H. pylori infection or the H. pylori-associated diseases, peptic ulcer or chronic active gastritis, with any blood group phenotype, including Lewisb, blood group O, or both. CONCLUSION: No in vivo correlation between H. pylori infection or disease and Lewisb or H antigen could be demonstrated. Moreover, patients with H. pylori infection and disease have a distribution of blood group antigens similar to a control population.
BACKGROUND: We used a murine model of autoimmune myocarditis to investigate systematically whether serum markers of myocardial cell injury, that is, cardiac troponin T (TnT) and the MB isoenzyme of creatine kinase (CK-MB) are useful for the diagnosis of inflammatory heart disease. METHODS AND RESULTS: Fifty-two A.SW mice were immunized with cardiac myosin to induce myocarditis. The disease was evident on day 12 after the initial immunization in 14 of 22 immunized mice, on day 16 in 7 of 10 mice, on day 19 in 6 of 10 mice, and on day 23 in 5 of 10. The severity of myocarditis increased between days 12 and 16 and remained constant thereafter. TnT was elevated in a considerable number of mice with myocarditis, resulting in a diagnostic sensitivity (number of marker elevations per number of mice with myocarditis) of 0.43 on day 12, 0.71 on day 16, and 0.50 on day 19. CK-MB elevations were not seen on day 12 but resulted in a diagnostic sensitivity of 0.71 on day 16 and of 0.33 on day 19. No elevations of CK-MB or TnT were observed on day 23. All elevations were specific for the disease, as none of the mice lacking myocarditis showed increased markers. CONCLUSIONS: In murine autoimmune myocarditis, TnT is a more sensitive marker for the disease than CK-MB. Elevations clearly indicate myocarditis, but negative test results do not exclude the presence of the disease. These data suggest that the determination of CK-MB and, in particular, of TnT, can be useful for the diagnostic evaluation of patients with suspected myocarditis.
A two-dimensional anisotropic model of cardiac ventricular muscle was used to study the effects of discontinuities (barriers), such as dead cells or high-resistance areas, on longitudinal plane-wave propagation. Problems in propagation appear when long barriers become thicker and their spacing closer. Short barriers with large widths and small spacing also cause propagation disturbances and significant delays in their vicinity. If the plane wave front propagates through the barriers, the velocity returns to near normal within one-length constant away from the end of the barrier region. For a funnel-like structure, an opening of 13 cells should exist for longitudinal plane wave propagation. For smaller openings, the ratio of openings required for propagation to occur when traveling from a narrow to a wider area of tissue is proportional to the anisotropy ratio, which can cause unidirectional block. Tortuosity, created by spatial distribution of dead cell barriers, can facilitate propagation by changing the effective impedance the wave front sees, and can create multiple local delays, which may result in discrepancies when measuring propagation velocity.
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Detailed investigation of cell growth and nucleolar organizer region associated argyrophilic proteins (Ag-NORs) is necessary to assess a possible impact of Ag-NOR quantification on the diagnosis and prognosis of tumours. In this study, cellular proliferation of the transitional-cell carcinoma cell line HOK-1 was modulated over a period of 11 days by starvation and subsequent medium addition. Proliferation was determined daily by DNA flow cytometric estimation of S-phase fraction (SPF) and mitotic index (MI) calculation. The number and area of interphase Ag-NORs were quantified by automated image analysis daily and the number of Ag-NOR bearing chromosomes in metaphase was counted. In interphase nuclei, Ag-NOR area showed a highly significant correlation with SPF (p < 0.0001) whereas interphase Ag-NOR number showed significant correlation with MI (p < 0.05). A positive relationship between the number of Ag-NOR bearing chromosomes in metaphases and cellular proliferation was also observed. There is variability in Ag-NOR quantity during interphase and metaphase depending on growth conditions in vitro. Correlations of the number of interphase Ag-NORs with the MI on one hand and Ag-NOR area with SPF on the other provide further evidence that distribution and quantity of Ag-NORs are strongly influenced by the cell cycle phase within the structural-functional unit of the nucleolus.