Anti-KANNO: A Novel Alloantibody Against a Red Cell Antigen of High Frequency

We encountered a broadly reactive red cell alloantibody in 1991, reacting unlike any other known antibody, and named it anti-KANNO after the first patient. A total of 28 cases of anti-KANNO in the Japanese literature were reviewed. To distinguish KANNO from other antibodies against high-frequency antigens, including anti-JMH, anti-Ch/Rg, and anti-Jr^a, we conducted serologic studies with proteolytic enzyme and chemical treatments, complement sensitization against red cells, and serum neutralization techniques. Reactivity of anti-KANNO against red cells lacking high-frequency antigens and antisera to high-frequency antigens against KANNO cells were tested. Among the 28 patients, 26 were female, of whom 25 had a history of pregnancy. Red cells from patient KANNO were reactive with antisera against antigens of high frequency. Anti-KANNO reacted weakly with all cells known to lack high-frequency antigens. It reacted with 2-aminoethylisothiouronium bromide, so it can be distinguished from anti-JMH. Differences among anti-KANNO, anti-Ch/Rg, and anti-Jr^a emerged with enzyme-treated cells, complement-sensitized cells, and the addition of normal serum. As yet, there are no reports of hemolytic transfusion reaction or hemolytic disease of the fetus and newborn attributable to anti-KANNO. It appears that anti-KANNO is a newly characterized antibody more likely stimulated by pregnancy than by transfusion and with little or no clinical significance. Further surveillance and investigation of anti-KANNO, its antigen biochemistry, and its genetics are warranted.     

Papillary fibroelastoma in the left ventricular outflow tract

Summary We report a case of a papillary fibroelastoma originating from the left ventricular endocardium in the outflow tract which was discovered by echocardiography in an asymptomatic patient. Two echocardiographic features were observed: (1) the tumor surface was smooth, and characteristic papillary formation was not detected; and (2) the outline of the mass was clearly defined as a dense echo, with the central, radiolucent, portion surrounded by a highly refractive linear echo at the level of the maximum diameter of the mass. The excised tumor was covered with a gelatinous substance that masked multiple papillae on the surface, but its echolucent center could not be explained by the pathology of the tumor which was solid centrally. Our case indicates that a papillary fibroelastoma may sometimes show echocardiographic findings similar to those of a myxoma, although other investigators have not noted the smooth surface and the echolucent center makes it indistinguishable from a myxoma. Thus, in some cases, it is difficult to distinguish papillary fibroelastoma from myxoma by echocardiography.     

Demonstration of three distinct immunological disorders on erythropoiesis in a patient with pure red cell aplasia and autoimmune haemolytic anaemia associated with thymoma

A patient with pure red cell aplasia (PRCA) and autoimmune haemolytic anaemia (AIHA), associated with a thymoma which had already been removed, was studied in order to investigate the pathogenesis of PRCA and AIHA. The autoantibody eluted from the surface of the patient's red blood cells (RBC) reacted with the large E antigen of the Rh complex. Immunoglobulin-G (IgG) purified from the patient's serum suppressed CFU-E and BFU-E but not CFU-GM colony formation in the presence of complement. This antibody was not adsorbed with large E antigen. T-lymphocytes in the bone marrow suppressing autologous CFU-E and BFU-E colonies were demonstrated. Thus, three distinct immunological disorders on erythropoiesis were present in this patient with PRCA and AIHA associated with thymoma in a thymectomized state.     

Changes in the isolated delayed component as an endpoint of catheter ablation in arrhythmogenic right ventricular cardiomyopathy: predictor for long-term success

Introduction: Although successful ablation of ventricular tachycardia (VT) is feasible in arrhythmogenic right ventricular cardiomyopathy (ARVC), long-term recurrence is common. The aim of this study was to assess the usefulness of a change in the isolated delayed component (IDC) as an endpoint of the catheter ablation in ARVC.
Methods and Results: Eighteen patients (48 ± 11 years) with ARVC were studied. Detailed endocardial mapping of the right ventricle (RV) was performed during sinus rhythm. IDCs were recorded in 16 patients and the latest IDCs were related to the VT circuit. Catheter ablation was carried out in the areas with the IDCs. At the end of the session, the IDC was electrically dissociated in one, disappeared in five, exhibited second-degree block in one, was significantly delayed (≥50 ms) in three, and remained unchanged in six. The change in the IDC was correlated with the change in the type II/III late potentials in the signal-averaged electrocardiography (ECG) and the inducibility of the clinical VT after the ablation. During a follow-up of 61 ± 38 months, VT recurred in six. The patients with a changed IDC had a significantly lower VT recurrence than those with no IDC or an unchanged IDC (P < 0.02).
Conclusion: In patients with ARVC, (1) the IDCs during sinus rhythm are related to the clinical VT and can be a target for the ablation, (2) a change in the IDC can be used as an endpoint, and (3) qualitative analyses of the serial signal-averaged ECGs may be useful for the long-term follow-up.     

Metachronous solitary mediastinal lymph node metastases of hepatocellular carcinoma treated by video‐assisted thoracic surgery twice: Report of a case

Solitary mediastinal lymph node metastasis of hepatocellular carcinoma (HCC) is rare. We report a case of metachronically solitary mediastinal metastases of HCC treated by video‐assisted thoracic surgery (VATS) twice. A 66‐year‐old man underwent repeated laparoscopic radiofrequency ablation or trans‐arterial catheter chemo‐embolization against HCC for more than 10 years. The level of alpha fetoprotein protein was elevated, and radiological modalities including FDG‐PET revealed solitary mediastinal tumor metachronically. VATS was performed bilaterally twice. The postoperative course was uneventful and there had no recurrence of extra‐hepatic metastases and tumor markers are within normal limits at 18 months after second VATS. VATS is a minimally invasive and useful procedure for solitary mediastinal lymph node metastasis of HCC. If primary HCC was controlled and lymph node metastasis was solitary, mediastinum lymphadenectomy using VATS might give good short and long term results.     

Therapeutic action of 5-HT3 receptor antagonists targeting peritoneal macrophages in post-operative ileus

Background and Purpose

Post-operative ileus (POI) is induced by intestinal inflammation. Here, we aimed to clarify the effects of 5-HT₃ receptor antagonists against POI.

Experimental Approach

We administered three 5-HT₃ receptor antagonists, ondansetron, tropisetron and palonosetron, to a mouse model of POI induced by surgical intestinal manipulation (IM). Immunohistochemistry, intestinal transit, inflammatory mediator mRNA expression and 5-HT content were measured. In some experiments, 5-HT₃A receptor null mice were used.

Key Results

Three 5-HT₃ receptor antagonists reduced IM-induced infiltration of inflammatory CD68-positive macrophages and myeloperoxidase-stained neutrophils. Ondansetron exhibited no anti-inflammatory actions in 5-HT₃A receptor null mice. Ondansetron inhibited expression of the chemokine CCL2, IL-1β, IL-6, TNF-α and iNOS mRNAs up-regulated by IM, and also ameliorated the delayed gastrointestinal transit. Peritoneal macrophages, but not most infiltrating monocyte-derived macrophages, expressed 5-HT₃ receptors. IM stimulation increased the 5-HT content of peritoneal lavage fluid, which up-regulated mRNA expression of proinflammatory cytokines in peritoneal macrophages. Immunohistochemical localization of 5-HT₃ receptors suggests that ondansetron suppressed expression of these mRNAs in activated peritoneal macrophages, adhering to the serosal region of the inflamed intestinal wall.

Conclusion and Implications

5-HT₃ receptor antagonists were anti-inflammatory, mainly targeting peritoneal macrophages expressing these receptors. They also restored the delayed gastrointestinal transit by IM. 5-HT₃ receptor antagonists should be therapeutically useful agents against POI.