An Unusual Difficulty in Blood Grouping: Interference by Soluble Antigen in a Patient's Serum

Difficulty was experienced in determining whether a patient was group B or group O. This was apparently due to the escape of fluid containing a large amount of B blood group substance into the circulation from a pseudo-mucinous ovarian cyst. The blood group substance in the cell suspension partially neutralised the anti-B agglutinin in the grouping serum, so that weak or negative agglutination reactions were obtained.

Résumé

Des difficultés se sont présentées pour déterminer si un patient était du groupe B ou du groupe O. Ceci était dû apparemment à la présence dans la circulation de liquide contenant une très grande quantité de substances de groupe B provenant d'un kyste mucolde de l'ovaire. Cette substance de groupe sanguin, présente dans la suspension érythrocytaire, neutralisait partiellement l'agglutinine anti-B si bien que l'on obtenait des réactions faibles, voire négatives.

Zusammenfassung

Bei einer Patientin erwies es sich als schwierig festzustellen, ob sie der Blutgruppe B oder 0 angehörte. Die Schwierigkeiten bei der Gruppenbestimmung beruhten darauf, daß aus einer pseudomuzinösen Ovarialzyste Flüssigkeit, die große Mengen B-Blutgruppensubstanz enthielt, in den Kreislauf gelangt war. Die in der Zellaufschwemmung enthaltene B-Substanz vermochte die Anti-B-Antikörper der Testseren soweit zu hemmen, daß nur schwache oder negative Reaktionen zustande kamen.     

Cardiac risks and management of complications in pregnant women with congenital heart disease

There are a growing number of women with congenital heart disease reaching adulthood and contemplating and/or undergoing pregnancy. However, pregnancy imposes hemodynamic stress on the heart and this can result in maternal, fetal and neonatal complications. Most women with congenital heart disease do well during pregnancy, but some women with high-risk cardiac lesions will not tolerate the hemodynamic changes of pregnancy. Physicians must be aware of the potential risks for the mother both during and after pregnancy, the risks to the fetus and neonate, and the risks and benefits of medications and procedures used during pregnancy. For women with complex cardiac conditions, management during pregnancy benefits from multidisciplinary care involving cardiologists with expertise in pregnancy, obstetricians with expertise in maternal fetal medicine, neonatologists and obstetric anesthetists, among others. This review will focus on the cardiac risks faced by women with congenital heart disease; particularly those at high risk, and on management strategies to mitigate risk and address cardiac complications.     

Syk‐Induced Phosphatidylinositol‐3‐Kinase Activation in Epstein–Barr Virus Posttransplant Lymphoproliferative Disorder

Posttransplant lymphoproliferative disorder (PTLD)‐associated Epstein–Barr virus (EBV)+ B cell lymphomas are serious complications of solid organ and bone marrow transplantation. The EBV protein LMP2a, a B cell receptor (BCR) mimic, provides survival signals to virally infected cells through Syk tyrosine kinase. Therefore, we explored whether Syk inhibition is a viable therapeutic strategy for EBV‐associated PTLD. We have shown that R406, the active metabolite of the Syk inhibitor fostamatinib, induces apoptosis and cell cycle arrest while decreasing downstream phosphatidylinositol‐3′‐kinase (PI3K)/Akt signaling in EBV+ B cell lymphoma PTLD lines in vitro. However, Syk inhibition did not inhibit or delay the in vivo growth of solid tumors established from EBV‐infected B cell lines. Instead, we observed tumor growth in adjacent inguinal lymph nodes exclusively in fostamatinib‐treated animals. In contrast, direct inhibition of PI3K/Akt significantly reduced tumor burden in a xenogeneic mouse model of PTLD without evidence of tumor growth in adjacent inguinal lymph nodes. Taken together, our data indicate that Syk activates PI3K/Akt signaling which is required for survival of EBV+ B cell lymphomas. PI3K/Akt signaling may be a promising therapeutic target for PTLD, and other EBV‐associated malignancies.     

von Willebrand factor released from Weibel-Palade bodies binds more avidly to extracellular matrix than that secreted constitutively

Large multimers of von Willebrand factor (vWf) are released from the Weibel-Palade bodies of cultured endothelial cells following treatment with a secretagogue (Sporn et al, Cell 46:185, 1986). These multimers were shown by immunofluorescent staining to bind more extensively to the extracellular matrix of human foreskin fibroblasts than constitutively secreted vWf, which is composed predominantly of dimeric molecules. Increased binding of A23187-released vWf was not due to another component present in the releasate, since releasate from which vWf was adsorbed, when added together with constitutively secreted vWf, did not promote binding. When iodinated plasma vWf was overlaid onto the fibroblasts, the large forms bound preferentially to the matrix. These results indicated that the enhanced binding of the vWf released from the Weibel-Palade bodies was likely due to its large multimeric size. It appears that multivalency is an important component of vWf interaction with the extracellular matrix, just as has been shown for vWf interaction with platelets. The pool of vWf contained within the Weibel-Palade bodies, therefore, is not only especially suited for platelet binding, but also for interaction with the extracellular matrix.     

Hematologic and immunomodulatory effects of an interleukin-1 receptor antagonist coinfusion during low-dose endotoxemia in healthy humans

Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.     

软骨修复组织蛋白多糖代谢与一氧化氮合酶抑制剂的影响

目的:应用一氧化氮合酶抑制剂可改善骨性关节炎和风湿性关节炎软骨的代谢,作者前期的实验也证明一氧化氮合酶抑制剂能提高软骨修复组织的质量。实验进一步观察一氧化氮合酶抑制剂对软骨修复组织蛋白多糖代谢的影响。方法:实验于1999-06/2002-02在南方医科大学完成。①实验分组:取雄性新西兰兔24只,8月龄,体质量(2.5±0.2)kg。随机抽签法分为对照组、骨形态发生蛋白组和S-甲基异硫脲组,每组8只。②实验方法:将大白兔双侧股骨髁间关节面造成全层软骨缺损,对照组:软骨缺损不充填任何物质;骨形态发生蛋白组:缺损用骨形态发生蛋白纤维蛋白凝胶复合物充填;S-甲基异硫脲组:缺损应用胶原复合骨形态发生蛋白充填,术后按5mg/(kg·12h)皮下注射S-甲基异硫脲。术后1年麻醉后处死动物。③实验评估:应用组织切片番红O-快绿染色和图像分析技术,按照染色百分率、平均灰度(平均染色程度)和染色厚度(软骨厚度)指标来检测糖胺聚糖含量;应用Na235SO4掺入法检测软骨修复组织蛋白多糖合成。结果:纳入新西兰兔24只,均进入结果分析。①术后1年,对照组几乎无红色染色区域;骨形态发生蛋白组可见到少量的不均匀红色区域;S-甲基异硫脲组可见到较多均匀一致的红色染色区域。②S-甲基异硫脲组软骨修复组织番红O染色百分率为89.28%,明显高于骨形态发生蛋白组36.54%和对照组13.4%,S-甲基异硫脲组修复组织番红O-快绿染色平均灰度值134.5,分别为骨形态发生蛋白组平均灰度值56.8的2.5倍,为对照组26.4的7倍。软骨平均厚度S-甲基异硫脲组1.75cm分别为骨形态发生蛋白组0.76cm和对照组0.25cm的2倍和6倍。③Na235SO4掺入法结果显示,S-甲基异硫脲组[35S]摄入量明显高于骨形态发生蛋白组和对照组(P<0.01)。结论:诱导型一氧化氮合酶抑制剂S-甲基异硫脲的应用能明显增加软骨修复组织糖胺聚糖含量和蛋白多糖合成,对于软骨修复质量的提高有积极意义。     

Systematic review of the predictors of health service use in pancreatic cancer

Introduction: Pancreatic cancer (PC) has a dismal prognosis, with identified disparities in survival outcomes based on demographic characteristics. These disparities may be ameliorated by equitable access to treatments and health services. This systematic review identifies patient and service-level characteristics associated with PC health service utilisation (HSU). Methods: Medline, Embase, CINAHL, PsycINFO and Scopus were systematically searched between 1^st January, 2010 and 17 May, 2021 for population-based, PC studies which conducted univariable and/or multivariable regression analyses to identify patient and/or service-level characteristics associated with use of a treatment or health service. Direction of effect sizes were reported in an aggregate manner. Results: Sixty-two eligible studies were identified. Most (48/62) explored the predictors of surgery (n=25) and chemotherapy (n=23), and in populations predominantly based in the United States of America (n=50). Decreased HSU was observed among people belonging to older age groups, non-Caucasian ethnicities, lower socioeconomic status (SES) and lower education status. Non-metropolitan location of residence predicted decreased use of certain treatments, and was associated with reduced hospitalisations. People with comorbidities were less likely to use treatments and services, including specialist consultations and palliative care but were more likely to be hospitalised. A more recent year of diagnosis/year of death was generally associated with increased HSU. Academically affiliated and high-volume centres predicted increased treatment use and hospital readmissions. Conclusion: Findings of this review may assist identification of vulnerable patient groups experiencing disparities in accessing and using treatments and therapies.