Blood Culture-Negative Endocarditis

Blood culture-negative endocarditis is often severe and difficult to diagnose. Infective blood culture-negative endocarditis is classified into three main categories: (1) bacterial endocarditis with blood cultures sterilized by previous antibacterial treatment; (2) endocarditis related to fastidious microorganisms in which prolonged incubation is necessary; (3) true blood culture-negative endocarditis, due to intra-cellular bacteria that cannot be routinely cultured in blood with currently available. There are two major etiologies for noninfective endocarditis: (1) nonbacterial thrombotic endocarditis and (2) endocarditis related to systemic diseases (SLE and Behcet disease). Team approach including cardiologists, infection disease (ID) specialists, microbiologists, pathologist and immunologist is crucial for diagnosis and management of blood culture-negative endocarditis as it needs elegant and high-quality modern technics of histology, molecular analysis and essential epidemiological information

Hypertrophy and Unconventional Cell Division of Hepatocytes Underlie Liver Regeneration

SummaryBackgroundThe size of organs and tissues is basically determined by the number and size of their cells. However, little attention has been paid to this fundamental concept. The liver has a remarkable ability to regenerate after surgical resection (partial hepatectomy [PHx]), and hepatocytes account for about 80% of liver weight, so we investigate how the number and size of hepatocytes contribute to liver regeneration in mice. It has been generally accepted that hepatocytes undergo one or two rounds of cell division after 70% PHx. However, ploidy of hepatocytes is known to increase during regeneration, suggesting an unconventional cell cycle. We therefore examine cell cycle of hepatocytes in detail.ResultsBy developing a method for genetic fate mapping and a high-throughput imaging system of individual hepatocytes, we show that cellular hypertrophy makes the first contribution to liver regeneration; i.e., regeneration after 30% PHx is achieved solely by hypertrophy without cell division, and hypertrophy precedes proliferation after 70% PHx. Proliferation and hypertrophy almost equally contribute to regeneration after 70% PHx. Furthermore, although most hepatocytes enter cell cycle after 70% PHx, not all hepatocytes undergo cell division. In addition, binuclear hepatocytes undergo reductive divisions to generate two mononuclear daughter hepatocytes in some cases.ConclusionsOur findings demonstrate the importance of hypertrophy and the unconventional cell division cycle of hepatocytes in regeneration, prompting a significant revision of the generally accepted model of liver regeneration

唐宋における煉丹術の展開 -「外丹」の再定義をめぐって-

早大学位記番号:新8533早稲田大

Gastroduodenal Mucosal Injury in Patients Taking Low-Dose Aspirin and the Role of Gastric Mucoprotective Drugs: Possible Effect of Rebamipide

The present study was conducted to investigate the prevalence of mucosal injury in patients taking low-dose aspirin in Japan and examine the effect of gastric mucoprotective drugs on aspirin-related gastroduodenal toxicity. We selected 530 patients who had taken low-dose aspirin for 1 month or more after undergoing esophagogastroduodenoscopy from 2005 through 2006 at Teikyo University Hospital, Tokyo, Japan. Endoscopic records were retrospectively reviewed to determine the presence of massive bleeding and mucosal injury (ulcer or erosion). The influence of clinical factors, including co-administration of gastroprotective drugs, was also examined. Hemorrhage was observed in 25 patients (3.7%) and mucosal injury (36.2%) in 192 patients. The presence of Helicobacter pylori antibody was a significant risk factor associated with mucosal injury. Patients taking any gastroprotective drug showed a significantly lower rate of mucosal injury than those not taking these drugs. Patients taking rebamipide concomitantly with proton pump inhibitors or histamine 2 receptor antagonists had mucosal injury less frequently than those taking acid suppressants plus other mucoprotective drugs. In conclusion, these results show the possible gastroprotective effects of rebamipide, suggesting that it may be a good choice in aspirin users with gastroduodenal toxicity that is not suppressed by acid suppressants alone

Why is autophagy important in human diseases?

The process of macroautophagy (referred to hereafter as autophagy), is generally characterized by the prominent formation of autophagic vesicles in the cytoplasm. In the past decades, studies of autophagy have been vastly expanded. As an essential process to maintain cellular homeostasis and functions, autophagy is responsible for the lysosome-mediated degradation of damaged proteins and organelles, and thus misregulation of autophagy can result in a variety of pathological conditions in human beings. Although our understanding of regulatory pathways that control autophagy is still limited, an increasing number of studies have shed light on the importance of autophagy in a wide range of physiological processes and human diseases. The goal of the reviews in the current issue is to provide a general overview of current knowledge on autophagy. The machinery and regulation of autophagy were outlined with special attention to its role in diabetes, neurodegenerative disorders, infectious diseases and cancer