In vitro anti-tumour and cyto-selective effects of coumarin-3-carboxylic acid and three of its hydroxylated derivatives, along with their silver-based complexes, using human epithelial carcinoma cell lines

The chemotherapeutic potential of coumarin-3-carboxylic acid (C-3-COOH) and a series of three hydroxylated coumarin-3-carboxylic acid ligands, namely 6-hydroxy-coumarin-3-carboxylic acid (6-OH-C-3-COOH), 7-hydroxy-coumarin-3-carboxylic acid (7-OH-C-3-COOH) and 8-hydroxy-coumarin-3-carboxylic acid (8-OH-C-3-COOH), along with their corresponding silver-based complexes, namely 6-hydroxycoumarin-3-carboxylatosilver (6-OH-C-COO-Ag), 7-hydroxycoumarin-3-carboxylatosilver (7-OH-C-COO-Ag) and 8-hydroxycoumarin-3-carboxylatosilver (8-OH-C-COO-Ag), was determined using two human-derived carcinoma (A-498 and Hep-G2), along with two non-carcinoma human-derived cell lines (CHANG and HK-2). All of the ligands and their silver complexes induced a concentration-dependent cytotoxic effect. Furthermore, hydroxylation of C-3-COOH and its subsequent complexation with silver led to the production of a series of compounds with dramatically enhanced cytotoxicity, with 6-OH-C-3-COO-Ag having the greatest activity. Additionally, all of the metal-based complexes were selectively cytotoxic to both carcinoma-derived cell lines, relative to normal renal and hepatic cells. In comparative studies with cisplatin, and based on the IC(50) values obtained with Hep-G2 cells, it appeared that the coumarin-silver complexes were between 2 and 5.5 times more cytotoxic than cisplatin. All of the coumarin-silver complexes inhibited DNA synthesis, which did not appear to be mediated through intercalation. Furthermore, results obtained from Ames tests showed that all of the test agents and their phase I metabolites were non-mutagenic. Taken together, these findings suggest that both hydroxylation particularly in the 6th position and complexation with silver, served to significantly augment the cytotoxic properties of C-3-COOH, to yield a compound which acts as a cyto-selective agent, as it is a significant killer of cancer, relative to normal cells. We suggest that this group of compounds may have a therapeutic role to play in the successful treatment and management of cancer in man.     

模拟教学法可改善成人糖尿病患者的血糖控制

初级保健医师(primary care physicians,PCPs)对继续医学教育的需求很大.为了评估以病例为基础的模拟教学法是否可以提高初级保健医师对糖尿病的诊疗水平,美国明尼苏达州健康合作者研究基金会和医疗集团进行了相关的研究. 研究选择了美国明尼苏达州健康合作者研究基金会和医疗集团旗下的11个诊所的41名初级保健医师,随机分为参与模拟教学组和不参与模拟教学组.在模拟教学组中,给每位初级保健医师派发了1 2个2型糖尿病的模拟病例,这些病例都是针对研究人员在电子病历中观察到的初级保健医师诊疗水平的不足之处所专门设计的,每个模拟病例都需要初级保健医师在15分钟内完成诊疗过程.     

A rare case of foreign body impaction requiring oesophagotomy

We report a rare case of ingestion of a large stone in a male patient with a known psychiatric disorder. Failure of endoscopic removal necessitated retrieval of the impacted stone by an open oesophagotomy. This case highlights an important yet unusual presentation and management of an oesophageal foreign body.     

球囊导管扩张咽鼓管的初步研究

咽鼓管功能障碍是常见疾病，经内镜鼻球囊导管扩张咽鼓管是一种新的手术技术，本研究的目的是回顾性分析这种新技术的演化并报道其适应症、初步结果和并发症。     

Hematopoietic regulatory factors produced in long-term murine bone marrow cultures and the effect of in vitro irradiation

The nature of hematopoietic regulatory factors elaborated by the adherent (stromal) cells of long-term murine bone marrow cultures and the effect of in vitro stromal irradiation (XRT) on the production of these factors was investigated. Using an in situ stromal assay employing a double layer of semisolid agar, it was possible to demonstrate stromal elaboration of at least two colony-stimulating activities, ie, granulocyte/macrophage colony-stimulating activity (G/M- CSA) and megakaryocyte colony-stimulating activity (Meg-CSA). Exposure of the stroma to XRT resulted in dose-dependent elevations of both activities that correlated inversely with total myeloid cell mass as determined by concurrent reductions in total supernatant cell recoveries from irradiated cultures. Mixture experiments that combined control and irradiated stroma revealed that the hematopoietically active control stroma could block detection of XRT-related G/M-CSA elevations. These data implicate a local negative feedback mechanism in the regulation of hematopoiesis. Antiserum directed against purified L cell colony-stimulating factor (CSF) reduced granulocyte/macrophage colony formation in the target layer but did not effect the increased Meg-CSA. While a radioimmunoassay for L-cell type CSF was unable to detect significant differences in concentrated media from control and irradiated cultures, bioassays of these media revealed XRT-related G/M- CSA elevations. These results indicate that the G/M-CSA elaborated in these cultures is immunologically distinct from the Meg-CSA produced, and although distinct from L cell CSF, the G/M-CSA is crossreactive with the L cell CSF antiserum. Morphologic, histochemical, and factor VII antigen immunofluorescent studies were performed on the stromal cell population responsible for production of these stimulatory activities. In addition to "fat" cells, the stromal cells remaining after XRT were composed of two predominant cell populations. These included a major population of acid phosphatase and nonspecific esterase-positive macrophage-like cells and a minor population of factor VII antigen negative epithelioid cells.     

Macrophage subsets in atherosclerosis as defined by single-cell technologies

Macrophages play a major role in the pathogenesis of atherosclerosis. Many studies have shone light on the different phenotypes and functions that macrophages can acquire upon exposure to local cues. The microenvironment of the atherosclerotic plaque contains a plethora of macrophage-controlling factors, such as cytokines, oxidised low-density lipoproteins and cell debris. Previous research has determined macrophage function within the plaque mainly by using immunohistochemistry and bulk analysis. The recent development and rapid progress of single-cell technologies, such as cytometry by time of flight and single-cell RNA sequencing, now enable comprehensive mapping of the wide range of cell types and their phenotypes present in atherosclerotic plaques. In this review we discuss recent advances applying these technologies in defining macrophage subsets residing in the atherosclerotic arterial wall of mice and men. Resulting from these studies, we describe three main macrophage subsets: resident-like, pro-inflammatory and anti-inflammatory foamy TREM2^hi macrophages, which are found in both mouse and human atherosclerotic plaques. Furthermore, we discuss macrophage subset-specific markers and functions. More insights into the characteristics and phenotype of immune cells within the atherosclerotic plaque may guide future clinical approaches to treat disease. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.