Malignant Cystosarcoma Phyllodes Of Prostate

A case of malignant cystosarcoma phyllodes of the prostate is reported in a 45-year-old male. This tumor was composed of benign columnar or squamous cystic folds and sarcomatous stroma including rhabdomyomatous elements. The prostatic origin of the tumor was clearly proved by the unlabeled immunoperoxidase method. ACTA PATHOL. JPN. 34: 663–668, 1984.     

Antigenic variation of the Epstein–Barr virus nuclear antigen EBNA1 as revealed by monoclonal antibodies

The Epstein–Barr virus (EBV) nuclear antigen EBNA1 plays an essential role in the replication of EBV episomes in latently infected cells and is the only viral protein that is consistently expressed in all programs of latent EBV gene expression. In this study, four monoclonal antibodies (MoAbs) directed to a region (amino acid residues 442–530) of EBNA1 were generated. Competitive enzyme-linked immunosorbent assay (ELISA) experiments using biotinylated MoAbs showed that they recognized distinct epitopes. Reactivity of these MoAbs with various laboratory EBV strains and field EBV isolates was shown to be heterogeneous in that EBNA1 from certain strains (isolates) was recognized and that from others was not. All four MoAbs showed such heterogeneous reactivity, and moreover, each MoAb showed a distinct spectrum of reactivity with these EBV strains (isolates). These results demonstrate an extensive structural variation in this region of EBNA1 as predicted by previous sequencing studies. These MoAbs will be useful as probes to dissect this structural heterogeneity of EBNA1.     

The role of γδ T cells in priming macrophages to produce tumor necrosis factor-α

The secretion of tumor necrosis factor (TNF)-α from macrophages is regulated by both priming and triggering signals. We found that macrophages from mice lacking γδ T cells [T cell receptor (TCR) δ^?/- mice], which lack the gene encoding the δ chain, produced only small amounts of TNF-α in response to lipopolysaccharide (LPS) and showed a reduced level of expression of CD14. Pre-incubation of macrophages from TCR δ-/- mice with γδ T cells from their TCR δ^+/- littermates restored their capacity to produce TNF-α in response to LPS. The priming activity of γδ T cells was in part inhibited by neutralizing anti-interferon (IFN)-γ monoclonal antibodies. Collectively, these results suggest that γδ T cells play a role in priming macrophages to a steady state of activation via IFN-γ secretion, which allows them to produce TNF-α when exposed to LPS.     

Sequential T Cell Response Involved in Tumor Rejection of Sarcoma, Meth A, in Syngeneic Mice

We investigated the type of T cell response involved in Meth A tumor rejection in primary immune and hyperimmune syngeneic mice. It was found that a CD4⁺ T cell-mediated delayed-type hypersensitivity (DTH) response activating non-specific killer cells such as macrophages, NK and LAK cells, without a specific CD8⁺ cytotoxic T lymphocyte (CTL) response, was the major immune response leading to Meth A tumor rejection in primary immune mice. In contrast, the specific CD8⁺ CTL response was the major response leading to the tumor rejection, in addition to CD4⁺ T cell-mediated DTH response, in hyperimmune mice. Analysis of CD4⁺ T cell clones established from primary immune and hyperimmune spleen cells indicated that a CD4⁺ T cell clone (C9) of primary immune mice (although only one clone was established) was of Th1 type, and induced cytotoxicity in accessory cells by classic DTH in vitro. Eight CD4⁺ T cell clones were established from hyperimmune spleen cells. Six out of the eight clones were of the Th2 type and two were Th0-like. However, no Th1-type CD4⁺ T cell clone was established from hyperimmune spleen cells. All of these CD4⁺ T cell clones, even the Th2-type clones, were capable of inducing cytotoxicity in vitro in T cell-depleted accessory cells, as in an in vitro DTH response. We postulate on the basis of these results that the T cell response leading to Meth A tumor rejection in vivo sequentially changed from a CD4⁺ T cell-mediated classic DTH response to a CD8⁺ CTL response, in addition to a cellular response mediated probably by Th2-type cells, during the process of repeated immunization.     

A comparative study of degree of colorectal distention with manual air insufflation or automated CO2 insufflation at CT colonography as a preoperative examination

Objectives

The purpose of this study was to compare the degree of colorectal distention between manual insufflation using room air and automatic insufflation using carbon dioxide for computed tomography colonography performed as a preoperative examination for patients with colon cancer.

Materials and methods

Participants comprised 200 patients who underwent computed tomography colonography immediately after colonoscopy from October 2011–2012. The first 100 patients were examined using manual insufflation, and the remaining 100 patients were examined using automated insufflation. Two radiologists independently assessed colorectal distention using a 4-point scale in six segments: cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. Mean scores of the two radiologists were used to analyze whether any differences existed between techniques in terms of the degree of distention per segment.

Results

Mean distention values for the colonic lumen were better using the automated technique than with the manual technique in both positions (p < 0.05). In segments, distention was significantly better using the automated technique than using the manual technique in the sigmoid and descending colon for prone patients, and in all segments for supine patients.

Conclusions

Automated carbon dioxide insufflation offered significantly improved colorectal distention scores compared to manual room air insufflation.     

Haemophagocytic lymphohistiocytosis, interferon-gamma-naemia and Epstein-Barr virus involvement

Summary. To clarify the correlation between Epstein-Barr virus (EBV) involvement and hypercytokinaemia in haemophagocytic lymphohistiocytosis (HLH), we analysed serum interferon-gamma levels and EBV-DNA in biological specimens obtained from 25 HLH cases (23 children and two adults). We found that HLH patients showed a wide range of serum IFN-gamma levels from 0.2 to 1300 U/ml, with a median 126U/ml for EBV-DNA-positive (n = 9) and 4.5 U/ml for EBV-DNA-negative (n = 16) groups. The latter group could be classified further into a group with hyper-IFN-gamma-naemia (> 4.5 U/ml) (n = 8) and a group without hyper-IFN-gamma-naemia (n = 8). The survival of the hyper-IFN-gamma-naemic cases was significantly poorer than non-hyper-IFN-gamma-naemic cases. We conclude that EBV is probably involved in one third of the HLH cases, all of whom show hyper-IFN-gamma-naemia, and in the half of the HLH cases with hyper-IFN-gamma-naemia who have a rapidly fatal outcome.