A preliminary study of discrimination among the components of small pulmonary nodules by MR imaging: correlation between MR images and histologic appearance

PURPOSE: To investigate whether magnetic resonance (MR) imaging depicts the internal characteristics of small pulmonary nodules. METHODS: We reviewed MR images of 39 surgically resected pulmonary nodules 3 cm or less and compared the components within the nodules. In 22 malignant nodules, eight histologic components were characterized by signal and enhancement patterns on MR images. RESULTS: MR images obtained from any single sequence discriminated all components in 26 (67%) nodules, whereas the combination of images from various sequences allowed discrimination in 35 (90%). Fourteen of 16 components of aggregated tumor cells showed marked early enhancement. Although fibrotic and necrotic components showed no or slight early enhancement, nine of 10 fibrotic components showed hypointensity and six of seven necrotic components showed hyperintensity on T2-weighted images. Component characterization in eight histologies by MR imaging was possible in 71-100%. CONCLUSION: Our study demonstrated that MR imaging offers the possibility of high tissue-contrast resolution in small pulmonary nodules.     

Role of caspase-1 subfamily in cytotoxic cytokine-induced oligodendrocyte cell death

Oligodendrocytes are myelin forming cells in mammalian central nervous system. About 50% of oligodendrocytes (OLGs) undergo cell death in normal development. In addition, OLG cell deaths have been observed in demyelinating diseases including multiple sclerosis (MS). Clinical observations and in vitro cell culture studies have suggested that cytokines mediate OLG cell damage in multiple sclerosis (MS). Among the cytokines, tumor necrosis factor (TNF) is thought to be one of the mediators responsible for the damage of OLGs in MS. The administration of TNF-alpha to primary cultures of OLGs induced DNA fragmentation, and significantly decreased the number of live OLGs. Chemical inhibitors Ac-YVAD-CHO (a specific inhibitor of caspase-1 (ICE)-like proteases) enhanced the survival of TNF-alpha treated OLGs better than Ac-DEVD-CHO (a specific inhibitor of caspase-3 (CPP32)-like proteases). These results indicate that caspase-1-mediated cell-death pathway are activated in TNF-induced OLG cell death. Caspase-11 is involved in activation of caspase-1. Oligodendrocytes from caspase-11-deficient mice are partially resistant to TNF-induced OLG cell death. Our results suggest that the inhibition of caspase-1 sufamily may be a novel therapeutic approach to treat MS.     

The effect of the prostaglandin I2 analogue OP-2507 on adrenaline-induced pulmonary edema in rabbits and analysis of hemodynamic changes

This study was carried out to understand the onset mechanism of adrenaline (ADR)-induced pulmonary edema (PE) and the effect of drugs related to the arachidonate cascade in a rabbit model. ADR was administered intravenously by a bolus injection to the rabbits at 50, 75 and 100 microg/kg. To evaluate the severity of PE, the lung-water ratio (LWR) was calculated as a ratio of the difference between wet and dry lung weight to dry lung weight. The PE incidence and LWR exhibited a dose-dependent increase, and LWR correlated with the left atrial pressure (LAP). The involvement of the arachidonate cascade was evaluated by the co-administration of flurbiprofen, a cyclooxygenase inhibitor; ozagrel, a thromboxane synthase inhibitor; and OP-2507 (15-cis-(4-n-propylcyclohexyl)-6,17,18, 19,20-pentanor-9-deoxy-6,9-alpha-nitriloprostaglandin F1 methyl ester), a prostaglandin I2 analogue. Co-treatment of the rabbits with ADR and flurbiprofen resulted in an increase in LAP and the incidence of PE, whereas co-administration of ozagrel did not exhibit any significant changes in the measured parameters. Conversely, OP-2507 reduced the LAP, PE incidence and LWR when co-administered with ADR. Rabbits co-treated with OP-2507 displayed an improved cardiac function. The results of these studies demonstrated the effectiveness of OP-2507 in protecting the lung and cardiac function from the ADR-induced PE.     

Intrauterine therapy with cytomegalovirus hyperimmunoglobulin for a fetus congenitally infected with cytomegalovirus

Reported herein is a case of hydrops fetalis in which the cord blood expressed cytomegalovirus (CMV) antigen. Fetal ascites was removed from an infected fetus with hydrops in utero and 2.5 g CMV hyperimmunoglobulin was administered into the fetal abdominal cavity at 28 weeks gestation. After immunoglobulin administration, fetal ascites vanished, preload index of the inferior vena cava decreased and platelet count of the infant increased. However, despite intrauterine therapy and intensive neonatal care, the infant died soon after birth. The expression of CMV antigen in the nucleus of polymorphonuclear leukocytes in fetal cord blood indicated that the fetal hydrops was caused by CMV infection. When symptomatic CMV infection of a fetus is suspected from serological and ultrasound findings, further examinations should be performed for the diagnosis. Intrauterine immunoglobulin therapy could be one of the therapeutic options for the affected fetus.     

Enzymatic synthesis of a false cholinergic neurotransmitter: diethylaminoethyl acetate as a muscarinic agonist analog of acetylcholine

Diethylaminoethyl acetate, an acetylcholine analog, was formed upon the incubation of diethylaminoethanol and acetyl-CoA with bovine brain choline acetyltransferase (acetyl-CoA: choline O-acetyltransferase; EC 2.3.1.6). The new product co-chromatographed with authentic diethylaminoethyl acetate on thin layer plates, and its formation was proportional to the duration of incubation and enzyme concentrations. When tested on guinea-pig ileum, diethylaminoethyl acetate was found to be an agonist with an ED50 of 1.3 X 10(-4) M, compared to an ED50 of 2.0 X 10(-7) M for acetylcholine. The contraction of guinea-pig ileum induced by diethylaminoethyl acetate was blocked by atropine. Moreover, diethylaminoethyl acetate induced a secretion of alpha-amylase from isolated pancreatic acini cells; this effect was also blocked by atropine. It is entirely possible that diethylaminoethyl acetate can be a false cholinergic transmitter generated in vivo when drugs such as aprophen or procaine are administered to animals, since either of these drugs can undergo enzymatic hydrolysis to generate diethylaminoethanol. A method for the synthesis of radioactive diethylamino [1,2-14C]ethyl acetate was also described.     

Endoscopic Treatment of Superficial Gastric Cancer: Present Status and Future

Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues.