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Fifteen accessions and 3 cultivars of subterranean exnected for this site. It is concluded that lateclover (Trifolium subterranean L.) were sown in autumn in shallow stony soil south of Christchurch, New Zealand. The following growing season was atypical, with drought occurring briefly but one month earlier than usual, the rest of the season being wetter than usual. Contrary to previous results highest seed yields were given by mid- to lateseason flowering lines. Early flowering lines were severely disadvantaged by the early drought, resulting in seed yields of only 20-25 kg/ha. High seed yields were linked with the ability of lines to recommence flowering after drought and continue this for a prolonged period. Two late flowering accessions, 014454B and 014205B, yielded more than 200 kg/ha seed, outyielding the late flowering cv. Tallarook in spite of this cultivar having the same ability as the other two to reflower. Six highseed yielding lines gave naturally regenerated seedling numbers near to or exceeding 1000/m2. Apparent hardseededness at the time of autumn germination averaged 49% which was lower than expected for this site. It is concluded that late fldwering lines of subterranean clover should always be included in mixtures of this species for pasture to ensure adequate regeneration in wetter than normal seasons. Keywords: accessions, cultivars, flowering, hardseededness, regeneration, seed production, Trifolium subterraneum

Medicine has been identified as a profession for almost 3000 years based on a core premise that physicians have the right to evaluate their own quality. Because medicine is a profession and because of the special privileges granted to physicians by society, quality-based principles that evolved in the manufacturing business have been difficult to adapt to medical practice. Physicians learn from other physicians and medical literature. This leads to wide variation in what is considered best practice. Variation has complex association, including the variation in expert opinion, the complexity of medical knowledge, the variation in physician decision-making potential, and human error. Guidelines or algorithms are a strategy that are finding favor as a solution. The control of variation through guideline development, iterative refinement of guidelines, and feedback to physicians will improve medical practice. By removing variation, physicians can honor the fiduciary trust that they have made to patients, make reasoned decisions, improve outcomes, and focus attention on making medical improvements.

Pathologic descriptions of allograft rejection of all solid organs have long recognized vascular involvement in the rejection process. Renal allografts, the earliest allografts to be studied. commonly display vasculitis involving the arteries and arterioles of the kidney cortex with or without cellular infiltrates invading tubules[1]–[3]. This vascular inflammatory process, often termed acute vascular rejection, is frequently associated with allograft loss in spite of increased immunosuppressive therapy[2],[3]. Similarly, arteritis has been identified in cardiac allografts on endomyocardial biopsy, and has been associated with poor allograft survival[4],[5].

To develop evidence-based guidelines for (1) prostate re-biopsy after radiation and (2) radiation therapy with rising prostate-specific antigen (PSA) levels after radical prostatectomy in the management of patients with localized prostatic cancer.The American Society of Therapeutic Radiology and Oncology (ASTRO) challenged a multidisciplinary consensus panel to address consensus on specific issues in each of the two topics. Four well-analyzed patient data sets were presented for review and questioning by the panel. The panel sought criteria that would be valid for patients in standard clinical practice as well as for patients enrolled in clinical trials. Subsequent to an executive session that followed these presentations, the panel presented its consensus guidelines.Based on the data presented, the prostate re-biopsy negative rates ranged from 62% to 80% for patients with stage T1-2 tumors. The panel judged that prostate re-biopsy is not necessary as standard follow-up care and that the absence of a rising PSA level after radiation therapy is the most rigorous end point of total tumor eradication. Further, the panel judged that re-biopsy may be an important research tool. Based on the data presented, the long-term (5 years or more) PSA remission rate after salvage radiation therapy ranges from 27% to 45%. The panel requested results from prospective randomized trials to evaluate optimally this information. The panel judged that the total dose of radiation should be 64 Gy or slightly higher and that, in patients with or without radiation therapy, there is no standard role for androgen suppressant therapy for rising PSA values after prostatectomy.

This issue of the ARCHIVES includes previously unpublished protocols for the examination of specimens removed from patients with cancer of diverse sites. We provide a historical context for the development of these protocols and describe the process of development and approval. General information about the structure and content of the protocols is also provided. Cancer protocol development is an important step in the process of standardized cancer reporting. The value of such standardized reporting is discussed.

Breast cancer reports form an important part of the basis of clinical decision making for patients. Our objectives were to improve breast cancer reporting in the Urban Central Region in Utah of Intermountain Health Care in a clinically relevant manner and to show that the method chosen actually improved information transfer among physicians of breast cancer patients and led to durable changes in pathologist behavior. METHODS/INTERVENTION: Pathologists designed a synoptic report based on interviews with oncologists about what data were meaningful. The report format was piloted with one hospital pathology group, modified, and implemented in three hospitals. A report evaluation of missing information was done before, immediately after, and 2 years after the intervention. Oncologists were surveyed after 2 years to evaluate satisfaction with report format.Changing breast cancer reporting to a synoptic format significantly decreased information missing from pathology reports. Prior to implementation, 32 of 365 reports lacked some item(s) of pathology information desirable to clinicians; after the intervention, 8 of 250 reports contained missing information. After 2 years, 1 in 190 reports contained missing data elements. Synoptic breast cancer reports continued to be used by pathologists throughout the reporting period. Oncologists responding to a survey reported uniform satisfaction with the new reporting format.Pathologists are important members of the clinical oncology team. They provide patient-specific information crucial to patient care. Activities designed to improve the quality of reporting processes should use clinically relevant indicators of process improvement, such as measurement of missing information and satisfaction of clinical colleagues with format/quality of information.

Apoptosis has been implicated in myocardial reperfusion injury and in experimental transplantation rejection. One mechanism of apoptosis is through the interaction of the cell-surface Fas receptor on target cells and the Fas ligand that is expressed on cytotoxic T cells. The purpose of this study was to look for evidence of myocardial Fas receptor, Fas ligand, and apoptosis in a murine heterotopic heart transplantation model of chronic rejection/graft vasculopathy.Using the nick-end labeling technique, we examined a murine heterotopic heart transplantation model of chronic rejection/graft vasculopathy (strain B10.A to B10.BR) histologically for evidence of DNA fragmentation. MRNA for the Fas receptor, Fas ligand, and beta-actin was detected with reverse transcription-polymerase chain reaction.Hearts harvested after 30 and 60 days showed an intimal index of the allografts (0.5 +/- 0.1) (mean +/- standard error) that was at least five times more than syngeneic grafts and native (nontransplanted) hearts (p0.01). In situ nick end-labeling of partially degraded DNA with terminal deoxynucleotydil transferase showed an increase in apoptotic cells in allografts and syngeneic grafts compared with native hearts. Reverse transcription-polymerase chain reaction detected equal myocardial RNA signal intensity of Fas receptor and beta-actin in allografts, syngeneic grafts, and native hearts. In contrast, allografts showed a strong signal for the Fas ligand mRNA, a signal not seen in syngeneic grafts or native hearts.Apoptosis is occurring in both allografts and syngeneic grafts in this murine model of chronic rejection/graft vasculopathy, although distinct mechanisms may be involved.

Allograft rejection remains a major cause of morbidity and mortality. Cyclophosphamide, a nitrogen mustard, is a potent immunosuppressive agent with effects on both T- and B-lymphocytes, and thus may be effective in preventing further cellular and/or humoral rejection in cardiac transplant recipients with recurrent or recalcitrant rejection. We retrospectively reviewed the records of 320 surviving cardiac transplant recipients. Cyclophosphamide was substituted for azathioprine in 28 patients because of frequent allograft rejection. We then reviewed the rejection history of these 28 patients, specifically looking at rejection frequency, type (cellular, vascular or mixed), and treatment. Cyclophosphamide was substituted for azathioprine at an average of 8.4 +/- 2.8 months after transplantation. Despite a 56.0% reduction in prednisone dose (p0.001), at least a threefold reduction in rejection frequency (p0.001) was observed, while cyclosporine levels were unchanged. Twenty-eight percent of the patients did not experience even mild rejection after beginning therapy with cyclophosphamide, 55% had 1 or 2 subsequent mild or moderate rejection episodes, and only 17% had more than two subsequent episodes of mild or moderate rejection. Overall, the number of treated rejection episodes decreased from 0.37 episodes per patient month with azathioprine to 0.10 episodes per patient month on therapy with cyclophosphamide. Separating the patients into two groups based on the predominant rejection type (cellular vs. vascular) occurring at the time of cyclophosphamide substitution revealed a similar reduction in cellular and vascular rejection in each respective group. While white blood cell count decreased by 16%, cyclophosphamide was not discontinued in any patient due to leukopenia, and no change was noted in hematocrit. Cyclophosphamide appears to be safe and effective in maintenance immunosuppression and may reduce rejection frequency in some patients with frequently occurring allograft rejection without necessitating the augmentation of either corticosteroids or cyclosporine.

Short-term studies suggest that cardiac transplant immunosuppression without maintenance corticosteroids is feasible in selected patients. However, concern exists as to the long-term effects, specifically the possibility of increased morbidity and mortality because of late allograft rejection and allograft coronary artery disease.We retrospectively reviewed the records from 441 consecutive heart transplantation procedures done in 416 patients with use of an immunosuppressive protocol that attempted corticosteroid withdrawal within 2 months of transplantation. forty-two patients died or underwent retransplantation during the first 3 months and were excluded from further analysis. Analysis focused on demographic and long-term outcome variables (including death, rejection, retransplantation, and infection).Thirty percent (111) of eligible patients (374) met the definition of successful early steroid withdrawal. Only male gender independently predicted successful withdrawal. Mortality, both short and long term, was significantly lower in patients in whom successful early withdrawal from corticosteroids was achieved than in patients in whom the early attempts failed (1.7% per year versus 4.7% per year; p0.0001). The prevalence of late acute allograft rejection (more than 1 year after transplantation) was lower in patients successfully withdrawn from steroid therapy early after transplantation (0.07 pt-yr of follow-up versus 0.15 pt-yr; p = 0.002). Multivariate analysis of the entire group identified incidence of infection (p = 0.001), older age (p = 0.001), failed early steroid withdrawal (p = 0.006), and female gender (p = 0.016) as independent predictors of mortality.Successful early corticosteroid withdrawal identifies a subgroup of "immunologically privileged" patients with a low risk for long-term mortality and is not associated with an increased prevalence of late rejection or clinically significant coronary artery disease.

Critical analysis of the evidence supporting the use of prognostic markers is needed for these to be used most appropriately in patient management. The College of American Pathologists recently sponsored a national conference to review the status of tumor markers for carcinomas of the breast, colon, and prostate gland. The conclusions of the Prostate Cancer Working Group are presented in this report. Currently, the TNM (Tumor, Lymph Node, Metastasis) staging system, histologic grading (Gleason system), and serum prostate-specific antigen are recommended for general use as prognostic markers in prostate cancer. Data support the use of DNA ploidy analysis in specific clinical settings, although general use is not currently recommended. The Working Group concluded that other markers do not have sufficient support in the literature to recommend routine use at the present time.

Mechanisms of graft rejection may be governed in part by the kind and degree of histocompatibility differences between donor and recipient. Cardiac allograft rejection was studied in three murine models selected to provide disparity at different major histocompatibility complex (MHC), minor lymphocyte stimulating (Mls) and other minor histocompatibility loci. Graft survival for the A.TL to A.TH combination (M3) was significantly longer (median day of rejection 15.0 days) than both the B10.A to AKR (M2) or the C57BL/6 to C3H/HeN (M1) donor-recipient combinations (median days of rejection: 9.0 days and 9.0 days respectively; P < 0.001). The infiltration of grafts by T cells was examined by removal of grafts serially post-transplantation and culturing mechanically disrupted graft tissue with interleukin-2 (IL-2). Recovery of T cells by this method revealed highly reproducible characteristics (kinetic and phenotypic), unique to each donor-recipient combination. Cultures from M1 and M2 grafts had differing CD4/CD8 T-cell ratios at days 2 (1.8 versus 0.7, respectively) and 4 (1.6 versus 0.1, respectively) post-transplantation. The M3 model differed from M2 (at days 4, 8 and 10) and from M1 (at days 8 and 10). At these times, cultures of M3 grafts contained a significantly increased percentage of CD4 cells and significantly decreased percentage of CD8 cells (CD4/CD8 ratios 0.9-1.3) by comparison with M1 (CD4/CD8 ratios 0.02-0.04) and M2 (CD4/CD8 ratios 0.1-0.02). Long-surviving M3 grafts (greater than 30 days post-transplantation) were compared with grafts removed immediately upon cessation of graft function (days 14, 15 and 18 post-transplantation). There was a significant difference between these groups in the ratios of CD4/CD8 T-cell ratios (1.1 versus 0.4, respectively). This study suggests that the cellular rejection mechanism of a graft is a variable process driven by the individual histocompatibility antigen disparity between donor and recipient. These findings may have diagnostic and therapeutic applications in organ transplantation.

In this study, we quantitatively evaluated the intensity and extent of prostate-specific acid phosphatase in immunocytochemically stained prostate carcinoma tissue sections by using a dual-wave-length-based image processing technique. Tissue sections were doubly stained in a standard way, i.e., prostate-specific acid phosphatase was immunocytochemically labeled by peroxidase-antiperoxidase (PAP) technique using diaminobenezidene (DAB) as the substrate and hematoxylin as a nuclear counterstain. Statistical analysis in this study indicated that the quantitative measures of the prostate-specific acid phosphatase staining (PAP-DAB) are reproducible. We found that the quantitative intensity was generally proportional to the subjective intensity (graded as 1 to 4+) of PAP-DAB. Although the quantitative extent measurements compared with the subjective estimates of the percentage of tumor showing staining with PAP-DAB had a similar tendency, there were significant overlaps between extent of tumor staining falling in the mid-ranges. Because subjective grading of immunocytochemical prostate-specific acid phosphatase has been thought to be a useful marker of tumor differentiation in patients with prostate carcinoma, we also evaluated the relationship of the quantitative measures of PAP-DAB staining to other predictors of patient outcome, including histologic grades (Gleason score and MD Anderson grading scheme) and clinical stage. We confirmed that quantitative intensity and extent of PAP-DAB staining were independent of histologic grades and stage, just as the subjective measures of intensity and extent were found to be. Possible explanations of this lack of correlation are discussed.

Human cardiac allograft-infiltrating lymphocytes were studied by in vitro expansion in interleukin-2. Of 28 graft-infiltrating lymphocyte cultures from 17 recipients, 17 were comprised predominantly of CD4+ T cells and 10 predominantly CD8+ T cells; one culture had equal numbers of CD4+ and CD8+ cells. The mean percentages (+/- SE) of T-cell subsets for all cultures were as follows: CD4+, 49% +/- 29%; CD8+, 42% +/- 31%. No correlation was observed between the culture phenotype and histologic findings, length of time from transplantation, or number (or class) of mismatched HLA antigens. N-alpha-benzyloxycarbonyl-L-lysine thiobenzyl ester serine esterase (BLT-SE) is an enzyme associated with intracellular cytotoxic T-cell granules and with target-cell destruction. Sixteen cultures were tested for BLT-SE activity and had significantly increased enzyme activity as compared to untreated peripheral blood mononuclear cells from healthy control subjects (p0.002), or interleukin-2-treated control cells (p0.05). A low percentage (0.4% +/- 0.2%) of cells in the graft-infiltrating lymphocyte cultures expressed the phenotypic marker NKH-1, suggesting that the source of BLT-SE in these cultures was not natural killer or lymphokine-activated T cells. Elevated BLT-SE was observed in five of ten cultures containing predominantly CD4+ cells and five of six cultures containing predominantly CD8+ T cells. Mixed phenotype graft-infiltrating lymphocyte cultures depleted of either CD4+ or CD8+ T cells retained BLT-SE activity. Thus both CD4+ and CD8+ graft-derived T cells can produce this enzyme although much greater variability in enzyme production was seen for CD4+ T cells.(ABSTRACT TRUNCATED AT 250 WORDS)

On the basis of our experience with prospective observation of immunofluorescence microscopy in 5775 biopsy specimens from 335 consecutively followed heart transplant cases, we describe the immunofluorescent method in detail and the potential artifacts and method of interpretation of the findings. A strategy for use of the method on the basis of the experience of the authors is proposed.

We have prospectively monitored 268 patients by our previously described method of routine immunofluorescence of endomyocardial biopsy specimens. We have classified these patients according to their rejection pattern: cellular, vascular, and mixed. The criteria for these designations have been previously described. In this study we retrospectively reviewed coronary angiograms of these patients to assess the presence and time-course of developing allograft coronary artery disease. All available explanted hearts and postmortem hearts were also assessed by light microscopic examination for acute coronary vasculitis and allograft coronary artery disease and by immunofluorescent microscopy for vascular immune complex deposition in a manner identical to immunofluorescent microscopic examination of endomyocardial biopsy specimens. Patients were also monitored for sensitization to immunoprophylactically administered murine monoclonal CD3 antibody (OKT3) and those demonstrated to be sensitized were separately analyzed. Clinical features and treatment of patients were retrospectively reviewed. We found that 141 patients could be classified as having cellular rejection, 76 as having vascular rejection, and 52 as having a mixed rejection pattern. The allograft survival in vascular rejection patients was significantly worse than in allografts of patients with cellular or mixed rejection, confirming our earlier results. Most importantly, we found a significant difference in the time to the development of allograft coronary artery disease based on the rejection pattern. This difference existed whether or not patients sensitized to OKT3 were excluded from evaluation. Patients with mixed rejection had an intermediate time to the development of allograft coronary artery disease between that of patients with cellular and vascular rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

The aim of this study was to develop a method of quantitating prostate-specific acid phosphatase (PSAP) in histologic sections of prostate tumor tissue labeled with the peroxidase-antiperoxidase (PAP) complex technique using diaminobenzidine (DAB) as a substrate. Studies of PAP-DAB- and hematoxylin-stained prostate tissue sections were performed with a black-and-white, computerized microscope image system. The mass of brown reaction product generated in PAP-DAB staining was the indicator of PSAP intensity. The mass of brown reaction product was determined by using a dual wavelength method in which two 10-nm bandpass filters, peaked at 450 and 510 nm in wavelength, were used. The wavelength-dependent ratio of mass absorptivity of PAP-DAB stain (brown product) and that of hematoxylin (blue product) were estimated at wavelengths of 450 and 510 nm by using slides stained with only PAP-DAB or hematoxylin. The accuracy of the mass measurements, investigated by relating the measurement to the true mass of the brown PAP-DAB product, is reported. There was no significant difference between the measurements at magnifications of 10x, 20x, 40x or 60x in the reproducibility investigation. The PSAP stain intensity was quantitatively determined by the difference of the PAP-DAB stain mass per pixel between the tumor and normal cell region. The relationship between the objective measurement and the conventional subjective grades is presented.

A total of 1,429 serum samples from 389 consecutive patients with acute chest pain were analyzed with the goal to aid the rapid diagnosis of acute myocardial infarction. To the best of our knowledge this is the largest and most comprehensive study on mid-infrared spectroscopy in cardiology. We were able to identify those signatures in the mid-infrared spectra of the samples, which were specific to either acute myocardial infarction or chest pain of other origin (angina pectoris, oesophagitis, etc). These characteristic spectral differences were used to distinguish between the cause of the donor's acute chest pain using robust linear discriminant analysis. A sensitivity of 88.5% and a specificity of 85.1% were achieved in a blind validation. The area under the receiver operating characteristics curve amounts to 0.921, which is comparable to the performance of routine cardiac laboratory markers within the same study population. The biochemical interpretation of the spectral signatures points towards an important role of carbohydrates and potentially glycation. Our studies indicate that the "Diagnostic Pattern Recognition (DPR)" method presented here has the potential to aid the diagnostic procedure as early as within the first 6 hours after the onset of chest pain.

We report one of the largest series of patients treated by radical prostatectomy followed for a minimum of 10 years. The tumor-free survival rate at 10 years seems superior to that achieved with alternative methods of treatment. Pathologic stage, DNA histograms, and tumor grade all correlate with prognosis but none is sufficiently powerful as an independent factor to allow selection of patients for surgery. Although a survival benefit has not been demonstrated, adjuvant treatment such as postoperative irradiation or early hormonal therapy may be indicated in patients with established poor prognostic factors.

Because administration of murine monoclonal anti-CD3 antibody (OKT3) may result in the formation of human antimouse antibody, which complexes with OKT3, we conducted this study to assess the incidence and effect of human antimouse antibody formation during prophylactic administration of OKT3 in heart transplantation. Human antimouse antibody developed in eight of 55 (14%) cardiac allograft recipients receiving OKT3 prophylaxis as measured by enzyme-linked immunosorbent assay. Additionally, two recipients had an inexplicable rise in CD3+ lymphocytes during therapy without detectable antibody. The outcome of these 10 sensitized recipients was compared with that of 45 nonsensitized recipients. Age, preoperative diagnosis, hemodynamics, and the need for intravenous inotropes or mechanical assistance before transplantation were similar in both groups. No female patients were in the sensitized group, whereas 33% of the nonsensitized group were female patients. A trend toward greater sensitization when prophylaxis was extended to 21 days (28%) compared with the more conventional 14-day administration (10%) was not statistically significant. Retransplantation because of rejection was required in a single patient in each group. Allograft survival was significantly lower by 3 months in the sensitized group, and allograft loss caused by rejection selectively accounted for that difference. In survivors, rejection frequency and infectious complications were similar. These findings suggest that sensitization to OKT3 occurs at low frequency after prophylactic administration in heart transplantation but is associated with an increased frequency of graft loss because of rejection.

The murine monoclonal CD3 antibody (OKT3) is effective in the treatment of refractory renal and cardiac allograft rejection and holds promise for improving rejection prophylaxis in heart transplantation. Although the administration of OKT3 is associated with many side effects, arteritis has not been previously reported. We report the development of acute necrotizing temporal arteritis associated with the deposition of mouse immunoglobulin G in a heart transplant recipient receiving OKT3 treatment of refractory rejection.

PURPOSE: To develop evidence-based guidelines for (1) prostate re-biopsy after radiation and (2) radiation therapy with rising prostate-specific antigen (PSA) levels after radical prostatectomy in the management of patients with localized prostatic cancer. DESIGN: The American Society of Therapeutic Radiology and Oncology (ASTRO) challenged a multidisciplinary consensus panel to address consensus on specific issues in each of the two topics. Four well-analyzed patient data sets were presented for review and questioning by the panel. The panel sought criteria that would be valid for patients in standard clinical practice as well as for patients enrolled in clinical trials. Subsequent to an executive session that followed these presentations, the panel presented its consensus guidelines. RESULTS AND CONCLUSIONS: Based on the data presented, the prostate re-biopsy negative rates ranged from 62% to 80% for patients with stage T1-2 tumors. The panel judged that prostate re-biopsy is not necessary as standard follow-up care and that the absence of a rising PSA level after radiation therapy is the most rigorous end point of total tumor eradication. Further, the panel judged that re-biopsy may be an important research tool. Based on the data presented, the long-term (5 years or more) PSA remission rate after salvage radiation therapy ranges from 27% to 45%. The panel requested results from prospective randomized trials to evaluate optimally this information. The panel judged that the total dose of radiation should be 64 Gy or slightly higher and that, in patients with or without radiation therapy, there is no standard role for androgen suppressant therapy for rising PSA values after prostatectomy.

A case of acute vascular rejection occurring in a cardiac allograft is presented. The rejection was characterized by prominent lymphocytic infiltration of the major coronary arteries in a pattern similar to that observed in acute vascular rejection occurring in renal allografts. Additionally, there was electron microscopic evidence of endothelial damage of smaller vessels. In addition to routine light microscopic evaluation of heart biopsies obtained in this case, immunofluorescent staining of biopsies for IgG, IgM, C3, Clq, fibrinogen, T cells, B cells, and Ia human leukocyte antigen (HLA-DR) was also performed. These studies suggest that antibodies may have been important in the terminal rejection episode described in this case. Furthermore, immunofluorescent staining detected continuing endothelial cell damage, reflected as Ia antigen positivity of allograft blood vessels, despite apparent improvement of rejection as judged by light microscopy.

We prospectively studied 551 sequential endomyocardial biopsies from 36 consecutive cardiac allografts. With the use of a combination of light microscopy (including careful evaluation of vascular changes) and immunofluorescence to detect the deposition of immunoglobulin and complement, we identified three patterns of allograft rejection, designated as cellular rejection, vascular (humoral) rejection, and mixed rejection. Cellular rejection was diagnosed with modified Billingham criteria. Vascular rejection was diagnosed by finding the combination of prominent endothelial cell swelling and/or vasculitis on light microscopy and the vascular deposition of immunoglobulin and complement by immunofluorescence. In such patients, cellular lymphoid infiltrates were uniformly absent at the time the vascular changes were detected. Mixed rejection consisted of findings of both cellular and vascular rejection occurring simultaneously. Twenty of 36 allografts exhibited cellular rejection; seven allografts showed vascular rejection, and nine allografts developed mixed rejection. The vascular (humoral) pattern of rejection was important to identify because the patients with this type of rejection had a significantly decreased survival compared with that of patients with cellular rejection (p less than 0.05). Survival in the mixed rejection category was intermediate. Positive donor-specific cross-match and/or panel-reactive antibody greater than or equal to 5% and systolic dysfunction were seen in three of the seven allografts with vascular (humoral) rejection but not in the other types. In the early period after transplant (up to 3 weeks after transplant), the only reliable identifying characteristics of patients with vascular (humoral) rejection were the presence of vascular immunoglobulin and complement assessed by immunofluorescence and endothelial cell swelling and interstitial edema as confirmed by histologic examination. We conclude that immunofluorescence should be routinely done on all heart biopsies for the first month after transplantation. Patients with vascular (humoral) rejection cannot be reliably identified by any other means.

In recent years heart transplantation has become an increasingly common therapeutic measure for cases of heart failure not amenable to other forms of management. Despite major advances, graft rejection continues to be the main cause of transplant failure. To expand our knowledge of the rejection process, we have grown lymphocytes from biopsy specimens obtained from potentially rejecting allografts. The growth of the lymphocytes requires the presence of interleukin-2 and was shown to correlate well with histologic criteria in identifying rejection (p less than 0.003, chi-square analysis). Of 125 biopsy specimens, 61 (49%) became positive for lymphocyte growth within 30 days. Of the biopsy specimens that were positive on culture, 54 (88%) were histologically diagnosed as rejecting, and seven (11%) were histologically nonrejecting. Of the 64 specimens that were negative on culture, 28 (44%) were histologically negative for rejection, and 36 (56%) were positive for some grades of rejection. Of these culture negative, microscopically positive specimens, however, 31 (86%) were associated with mild (grade 3) or equivocal (grade 2) rejection. Discrepancies between culture and histology appeared to be related to degree of rejection, quantity of sample, and sampling variation. Phenotypic identification of cultured cells showed that the suppressor/cytotoxic phenotype was the predominant cell type in all cultures (mean +/- standard error = 83% +/- 3% of cells). Antihuman mature inducer/helper T cell (OKT4+) T-lymphocytes in culture were associated with biopsy specimens obtained immediately before onset or at the beginning of rejection. Preliminary studies testing in vitro sensitivities of lymphocytes to antithymocyte globulin (ATG) and other control immunosuppressants not believed to function by direct cytolysis (methylprednisolone, cyclosporine, azathioprine) were undertaken. These yielded reproducible dose-response curves, and the drug concentration producing 50% cytotoxicity (LD50) was calculated for each drug-culture combination. The mean LD50 for ATG was in the range of in vivo therapeutic concentrations, whereas LD50 values for control drugs were threefold to twelvefold higher than therapeutic concentrations. Resistance to the effects of ATG showed a tendency to correlate with prolongation of rejection; however, a similar tendency was noted for control drugs, suggesting the possibility of a nonspecific mechanism of resistance to the effects of ATG. The technique of interleukin-2 lymphocyte culture from rejecting allografts promises to further our understanding of mechanisms of graft rejection.

Gamma-irradiation has been extensively utilized as a bone marrow ablative agent during human bone marrow transplantation. Although the effects of ionizing radiation on lymphoid and hematopoietic cells are well documented, little is currently known about its effect on the nonhematopoietic tissues which are important for the restoration of normal immune function. The vast majority of lymphocyte movement into peripheral lymph nodes takes place via the bloodstream and requires a specific receptor-ligand interaction between the lymphocyte and anatomically distinct postcapillary venules. Due to the importance of lymphocyte recirculation in the initiation and amplification of immune responses, an understanding of the radiosensitivity of the postcapillary venules may provide insight into the pathogenesis of the immune deficiencies commonly seen after bone marrow transplantation. Our studies disclosed that the ability of normal blood-borne lymphocytes to enter peripheral lymph nodes was markedly depressed (less than 50% of normal) in mice which had been exposed to 7.5 Gy of gamma-irradiation. This radiation-induced effect lasted longer than 6 months after irradiation and syngeneic reconstitution, and its magnitude was radiation-dose dependent. Immunochemical staining of the lymph node microvasculature with the monoclonal antibody MECA-325 established that the radiation protocol induced persistent anatomic changes in the lymphocyte-receptive areas of endothelium (high endothelial venules). These vessels developed the appearance of endothelial cell proliferation. Electron microscopy demonstrated significant intracellular edema, with virtual occlusion of many microvascular lumens by edematous endothelial cells. Lymph nodes from human bone marrow transplant recipients were found to exhibit similar ultrastructural changes. These studies for the first time demonstrate that doses of irradiation similar to those used to prepare bone marrow transplant recipients can have significant anatomic and functional sequellae on host endothelial cells.

Elements of Geography Physical and Cultural , Elements of Geography Physical and Cultural , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی