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61.
Endocardial infiltrates in human heart transplants: a serial biopsy analysis comparing four immunosuppression protocols 总被引:2,自引:0,他引:2
Endocardial mononuclear cell infiltrates were studied in 2,350 consecutive biopsies from 172 patients over a period ranging from 4 to 16 months post cardiac transplantation. The patients, otherwise unselected, were equally subdivided into four groups based upon the specific type of maintenance immunosuppression used. This was to allow for comparison of the effects of four separate commonly used recipient immunosuppression protocols, which could potentially influence the characteristics of the infiltrates. With azathiaprine-corticosteroid immunosuppression, endocardial infiltrates in otherwise normal biopsies were exceedingly rare, very minor, and invariably unifocal. Mild and moderate rejection were associated with a highly significant stepwise increase in incidence, prominence, and multifocality of endocardial infiltrates. In contrast, with each of the three cyclosporine-based recipient immunosuppression protocols which were evaluated, approximately 15% of biopsies with no evidence of rejection were associated with endocardial infiltrates. There was a wide range of variation in the prominence of the endocardial infiltrates present. Multifocal infiltrates were frequently encountered, the incidence of which was exclusively dependent upon the specific cyclosporine-based immunosuppression protocol used. With mild and with moderate rejection there was a significant stepwise increase in overall biopsy incidence of all endocardial infiltrates in each of the three groups, although there was no variation in relative prominence of the infiltrates, or in incidence of multifocality when biopsies without rejection were compared. The presence of conspicuous vascular spaces within endocardial infiltrates and significant extension of the infiltrates into the adjacent myocardium, with or without associated myofiber necrosis, were characteristic features of the most prominent endocardial infiltrates in all three cyclosporine-based immunosuppression groups. This constellation of changes has sometimes been referred to as "Quilty" effect. The relative incidence with which these particular features were encountered in association with endocardial infiltrates did not vary with rejection category of the biopsies. This study has shown that the presence of all forms of endocardial infiltrates, in the absence of concomitant rejection, is a characteristic manifestation of cyclosporine-based recipient immunosuppression, regardless of the specific protocol and cyclosporine dosage schedule. Under azathiaprine-based immunosuppression, endocardial infiltrates are almost invariably associated with rejection. It is postulated that cyclosporine-related endocardial mononuclear cell infiltration, in the absence of overt rejection, may result from a low level alloimmune response secondary to fluctuations in cyclosporine drug levels or related factors, and that the incidence with these infiltrates occur can be augmented during acute rejection episodes when the strength of the recipient immune response is magnified. 相似文献
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63.
It has been shown that fulminant acute rejection of rat cardiac allografts across a full haplotype disparity may occur as a direct result of adoptive transfer of sensitized W3/25+ MRC OX8- SIg- T helper/DTH syngeneic spleen cells to sublethally irradiated recipients. In order to establish the immunohistologic parameters of this form of rejection, allografts and recipient lymphoid tissue were analyzed using a panel of monoclonal antibodies of known cellular distribution. These data were compared with those obtained following reconstitution of irradiated allograft recipients with unseparated sensitized spleen cells, with unreconstituted irradiated donor recipient pairs, with unmodified first-set rejection, and with induced myocardial infarction of syngeneic heart grafts transplanted to normal and to sublethally irradiated recipients. Rejecting cardiac allografts transplanted to all reconstituted irradiated recipients were characterized by extensive infiltration with MRC OX8+ (T cytotoxic-suppressor, natural killer) cells even when this subset was virtually excluded from the reconstituting inocula. A similar proportional accumulation of MRC OX8+ cells observed at the infarct margins of syngeneic heart grafts transplanted to irradiated unreconstituted recipients greatly exceeded that present in normal nonirradiated controls. These data provide evidence that under conditions of heavy recipient irradiation, MRC OX8+ cells may be sequestered within heart grafts in response to nonspecific injury unrelated to the rejection process. Although there was no significant degree of MRC OX8+ cellular repopulation within organized secondary lymphoid tissues of irradiated animals over the study period, the density of ileal mucosal MRC OX8+ lymphocytes approximated normal at 7 days post-irradiation, raising the possibility that these cells could share a common origin with those sequestered within the heart grafts. Carbon+ MRC OX6+ macrophages were a significant component of the infiltrate in all rejecting cardiac allografts, as well as in all infarcted syngeneic heart grafts--providing further evidence that macrophage "activation" with expression of class II determinants may occur in response to nonspecific injury. In unmodified first-set rejection there was an intense B cell reaction in recipient spleens and lymph nodes. In the adoptive transfer model, marked B cell expansion was exclusively confined to the parathymic lymph nodes of irradiated allograft recipients reconstituted with the sensitized W3/25+, MRC OX8-, SIg- T helper/DTH donor cell inocula.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
64.
W B Dobyns V V Michels R V Groover B Mokri J C Trautmann G S Forbes E R Laws 《Annals of neurology》1987,21(6):578-583
We studied a family in which 4 persons from three generations had multiple cavernous malformations ("angiomas") of the central nervous system (CNS) and/or retina and found accounts in the literature of sixteen other families with this condition. In these families with familial cavernous malformation of the CNS and retina, 92% of pathologically documented vascular malformations were cavernous; 50% of those subjects affected had multiple CNS and/or retinal vascular malformations and 68% (excluding probands) were symptomatic. Cutaneous vascular lesions were an inconsistant manifestation. Autosomal dominant inheritance with high penetrance was confirmed. 相似文献
65.
Transitional cell carcinoma (TCC) of the urinary tract is multicentric [1]. In men, extension of TCC is more commonly seen in the prostatic urethra [2] than the anterior urethra. Retrograde urethrogram may demonstrate the extent of tumor "vegetation" in the urethra in a patient presenting with obstructive and irritative uropathic symptoms. 相似文献
66.
Sean Cowlishaw Olivia Metcalf Tracey Varker Caleb Stone Robyn Molyneaux Lisa Gibbs Karen Block Louise Harms Colin MacDougall H. Colin Gallagher Richard Bryant Ellie Lawrence‐Wood Connie Kellett Meaghan O'Donnell David Forbes 《Journal of traumatic stress》2021,34(1):46-55
Anger is an important dimension of affect and a prominent feature of posttraumatic mental health, but it is commonly overlooked in postdisaster settings. We aimed to examine the distribution and implications of significant anger problems in the aftermath of a natural disaster, via analyses of Beyond Bushfires survey data from 736 residents of rural communities 5 years after the 2009 Black Saturday bushfires in Victoria, Australia. Assessments included the five‐item Dimensions of Anger Reaction (DAR‐5) scale along with measures of PTSD, depression, and significant mental illness, and indicators of life satisfaction, suicidality, hostile aggressive behavior, and violence exposure. The results indicated that approximately 10% of respondents from areas highly affected by the bushfires scored above the provisional cutoff criteria for significant anger problems on the DAR‐5, which was a more than 3‐fold increase, OR = 3.26, relative to respondents from areas of low‐to‐moderate bushfire impact. The rates were higher among women, younger participants, and those who were unemployed, and co‐occurred commonly, although not exclusively, with other postdisaster mental health problems. Anger problems were also associated with lower life satisfaction, β = ?.31, an 8‐fold increase in suicidal ideation, OR = 8.68, and a nearly 13‐fold increase in hostile aggressive behavior, OR = 12.98. There were associations with anger problems and violence exposure, which were reduced when controlling for covariates, including probable PTSD. The findings provide evidence indicating that anger is a significant issue for postdisaster mental health and should be considered routinely alongside other posttraumatic mental health issues. 相似文献
67.
Marissa Forbes Blair G Darney Shaalini Ramanadhan Mary Earp Lauren Waldner-James Leo Han 《Contraception》2021,103(4):276-281
ObjectiveWe sought to assess how women interpret the information they find online about the overall safety and risk of infertility associated with abortion and cesarean delivery (CD).MethodsWe conducted an exploratory, prospective study tracking the internet searches of 100 reproductive-aged individuals who identify as women. We directed participants to search for information about either (1) whether surgical abortion or CD is safe or (2) the risk of infertility following surgical abortion or CD. Our data collection had 3 phases: baseline survey, directed internet search, and a postsearch survey. We analyzed participants’ pre- and postsurvey responses using bivariate tests and analyzed within-subject changes. We evaluated the sites they visited based on expert ratings of site content based on trustworthiness and slant.ResultsWomen perceived abortion as safer and less likely to cause infertility after their web searches than before (70% perceived abortion in the United States as very/completely safe presearch vs 92% postsearch; p < 0.02). Women's perceptions about CD did not change. Participants sought information from web pages that experts largely deemed trustworthy and lacking in slant.ConclusionsWomen's perceptions about abortion safety and risk can be influenced by information they find online; perceptions about CD safety and risk may be less influenced by online information.ImplicationsDisseminating high quality, user-friendly abortion information on highly ranked and easily findable websites can help women find evidence-based information and influence knowledge about abortion. 相似文献
68.
Proteome analysis involves the simultaneous resolution and display of proteins produced by an organism, followed by the quantitation, characterisation and identification of these proteins. As part of an ongoing study mapping and comparing the proteins expressed by various strains of the pathogenic bacterium Helicobacter pylori, we have resolved and identified 93 of the most abundant proteins expressed by type reference strain NCTC 11637. Proteins were separated by two-dimensional gel electrophoresis and stained with Coomassie G250. Intensely-stained spots were excised and digested with trypsin, and the resulting peptides were characterised by mass spectrometry. Proteins were then identified by correlating actual peptide profiles with theoretical profiles generated from published nucleotide sequences. Ninety-three of the most intensely-stained protein spots were identified as the products of 35 genes, giving a ratio of 2.7 protein gene-products per gene. The products of the tsaA, pfr, ureA and ureB genes were amongst several proteins present in multiple isoforms. Peptide mass fingerprinting data were used to identify probable post-translational protein modifications. These results suggest that H. pylori proteins are subject to a high degree of post-translational modification. Comparative proteomics of H. pylori strains should greatly assist in investigating the pathogenic properties of this bacterium. 相似文献
69.
The fall 1986 newsletters of the Council of Clinical Nurse Specialists (CCNS) and the Council of Primary Health Care Nurse Practitioners (CPHCNP) featured an editorial examining the similarities and differences between the advanced practice roles of the nurse practitioner and the clinical nurse specialist. The article, entitled "Editorial on Specialization in Advanced Nursing Practice" and written by Patricia Sparacino, MS, RN, chairperson CCNS, and Barbara A. Durand, EdD, RN, FAAN, of the CPHCNP appeared in Momentum, Volume 4, Number 2/1986, and Newsletter, Volume 9, Number 2/1986. This initial exploration into advanced practice roles in nursing elicited a wide variety of responses from affiliates of both councils which, in turn, prompted the executive committees of both groups to convene a joint meeting. In the spring of 1987 the executive committees of the CCNS and the CPHCNP met to review affiliate response to the editioral, further explore concerns, and plan futher action. At that time it was decided to survey all nursing programs in the United States which provide graduate education for one or both of the advanced practice roles. It was hoped that the information gained from such a survey would provide a basis for future determinations. Survey data was compiled and presented to another joint meeting of the executive committees of the CCNS and the CPHCNP on October 3, 1989. This article reports the data, findings, and reactions of the executive committees of the councils in order to obtain feedback from our colleagues. 相似文献
70.