Overexpression of the Del1 gene causes dendritic branching in the mouse mesentery

In the present study, we established transgenic mice overexpressing Del1, a ligand of integrins, to examine the effect of overexpression of Del1 on vascular morphogenesis. In the wild-type mouse, mesenteric vessels are shaped like rakes consisting of a long stalk and short branches at the periphery. In contrast, those in transgenic mice showed typical dendritic architecture consisting of a few large primary branches with smaller spreading branches. The phenotype of mice overexpressing Del1 suggests the existence of a tissue-specific mechanism for branching morphogenesis in the mesentery.     

Influence of the parameters of several pulse sequences on the image contrast: comparison between the two major contrast media

We compared the influences of the parameters of several pulse sequences using two major commercially available gadolinium (Gd) contrast media for MR imaging. The phantom of Gd solutions of various concentration (0.1 - 10mmol/L) was prepared, and was scanned with a 1.5T clinical MR unit, using a spin-echo T1-weighted sequence, 2DFLASH, 3DFLASH, and 3DVIBE. The signal intensity was measured and the contrast enhancement ratio (CER) was calculated and plotted as a function of Gd concentration. The results were compared between the pulse sequences, and between the contrast media as well. Both 3DFLASH and 3DVIBE showed higher CER than other two sequences, showing similar CER curve configuration. There was no significant difference both in CER value and CER curve configuration between the two contrast media for each pulse sequence.     

The effects upon electromagnetic flowmeter sensitivity of non-uniform fields and velocity profiles

The magnetic flux density of implantable electromagnetic blood flowmeter can not be made uniform, since the size of flowmeter probe must be very small for physiological reasons. The velocity distribution of blood flow is axially non-symmetrical everywhere in arteries. Mainly for the above reasons the blood flow can not be measured accurately by implantable electromagnetic flowmeter. In this paper the relation between induced electromotive force and flow rate for implantable electromagnetic flowmeters is presented, and the errors introduced by the factors mentioned above are discussed. In order to measure pulsatile or axially non-symmetrical flow accurately, appropriate flowmeter probes must be used. Some of these flowmeter probes are shown.     

Atypical Glomus Tumor in the Mediastinum: A Case Report with Immunohistochemical and Ultrastructural Studies

A case is reported of atypical glomus tumor occurring in the posterior inferior mediastinum of a 26-year-old woman complaining of severe back pain. The tumor was composed of atypical small, round tumor cells with scattered mitotic figures. In addition to sheet-like, diffuse proliferation of the tumor cells, some areas of the tumor contained small “glo-moid” cells arranged in organoid and hemangiopericytoma-like patterns. Immunohistochemically, many tumor cells were positive for muscle-type actins and a few cells were focally positive for desmin. Ultrastructural studies revealed smooth muscle features of tumor cells, that is, pinocytotic vesicles, external laminas, dense plaques, and occasional thin filaments with dense bodies. The patient remained well for 5 years and 4 months after the operation without additional radiation and chemotherapy. The tumor was diagnosed as an atypical, or low-grade malignant, glomus tumor morphologically. It seems important to recognize the presence of this type of tumor in sites other than extremities and to differentiate it from other malignant small, round cell tumors.     

Electron-dense deposition patterns and the outcomes of idiopathic membranous nephropathy in Japanese

A considerable diversity in prognosis is seen with membranous nephropathy (MN). In terms of pathological findings, the presence of tubulointerstitial lesions was emphasized as a poor prognostic factor. However, the glomerular factors affecting the long-term outcome of idiopathic human MN have remained unclear. We reviewed the initial clinicopathological factors affecting the primary and secondary outcomes in 105 patients with primary MN, as well as reviewing previous reports. Based on electron microscopic (EM) findings, we could divide patients into two subtypes and one subgroup; i.e., homogeneous type with a synchronous phase of electron-dense deposits, with large dense deposits (deep subgroup) and heterogeneous type with various phases of dense deposits. The homogeneous type showed no endstage renal failure, and had earlier remission as compared with the heterogeneous type. For the secondary outcome, heterogeneous type and deep subgroup were also independent risk factors. However, there was no significant difference in the final primary or secondary outcome for any treatment subgroups. These results indicated that our category of EM findings was a beneficial marker of the primary and secondary outcomes in MN; the homogeneous type of MN with synchronous phase of electron-dense deposits (except for the "deep" subgroup) had a good outcome.     

Effect of solvents and initiators on the cationic copolymerization of 1,3-dioxolane with 5-methyl-2,3-dihydro-2-furanone

The cationic copolymerization of 1,3-dioxolane ( 1 ) with 5-methyl-2,3-dihydro-2-furanone ( 2 ) which has two functional groups, a carbon-carbon double bond and a lactone ring, was carried out with three triethyloxonium salts (Et₃O⁺Y^?, Y^?: BF, FeCl and SbCl), with the boron trifluoride ethyl ether complex, and with tin tetrachloride in nitrobenzene, dichloromethane, and toluene at 0°C. On the basis of the NMR analysis of the microstructure of the copolymer, it was revealed that the growing species of 1 attacked exclusively the carbon-carbon double bond of 2 in the cross-propagation from 1 to 2 , regardless of the solvents and initiators used, except when triethyloxonium hexachloroantimonate was used as initiator. With the latter initiator, the ring opening reaction of 2 by the attack of the growing species of 1 occurred competitively with the usual vinyl addition, although the latter mode of reaction was predominant. The ring opening reaction of 2 with this initiator is probably caused by some specific interaction of monomer 2 with the counter anion.