Observation of self-binding in monolayer 3He

We report clear experimental signatures of the theoretically unexpected gas-liquid transition in the first three monolayer systems of (3)He adsorbed on graphite. The transition is inferred from the linear density dependence of the gamma coefficient of the heat capacity measured in the degenerate region (2≤T≤80 mK) below a critical liquid density (ρ(c0)). Surprisingly, the measured ρ(c0) values (0.6-0.9 nm(-2)) are nearly the same for all these layers in spite of their quite different environments. We conclude that the ground state of (3)He in strictly two dimensions is not a dilute quantum gas but a self-bound quantum liquid with the lowest density ever found.

Extravascular injection of sclerotic agents does not affect vessels in the rat: experimental implications for percutaneous sclerotherapy of arteriovenous malformations

OBJECTIVES

Sclerotherapy is useful for the treatment of arteriovenous vascular malformations. However, intravascular administration of sclerotic agents into small arteriovenous niduses is often difficult. Extravascular administration of sclerotic agents causes reduction of vascular flow on Doppler echo during clinical sclerotherapy. Therefore, we aimed to investigate whether the extravascular injection of sclerotic agents affects tiny vessels.

DESIGN

Animal study.

MATERIALS

The effect of extravascular injection of sclerotic agents on vessels was investigated using rat femoral and superficial inferior epigastric vessels.

METHODS

After surgical exposure of vessels, absolute ethanol, 5% ethanolamine oleate and 3% polidocanol were injected into perivascular surrounding tissues, and their effect on vessels was evaluated after 14 days using histology and coloured silicone rubber injection.

RESULTS

The integrity of the vascular lumen, endothelial cells and vascular patency were not affected by injection of sclerotic agents.

CONCLUSIONS

Attenuation of vascular flow of an arteriovenous shunt after extravascular injection of sclerotic agents is transient and/or trivial and does not cause disruption of vessels. Therefore, sclerotic agents should be delivered to obtain sufficient destruction of arteriovenous malformation lesions and blood flow.

Myasthenia gravis and neuromyelitis optica spectrum disorder: a multicenter study of 16 patients

OBJECTIVE

To describe 16 patients with a coincidence of 2 rare diseases: aquaporin-4 antibody (AQP4-Ab)-mediated neuromyelitis optica spectrum disorder (AQP4-NMOSD) and acetylcholine receptor antibody (AChR-Ab)-mediated myasthenia gravis (AChR-MG).

METHODS

The clinical details and antibody results of 16 patients with AChR-MG and AQP4-NMOSD were analyzed retrospectively.

RESULTS

All had early-onset AChR-MG, the majority with mild generalized disease, and a high proportion achieved remission. Fifteen were female; 11 were Caucasian. In 14/16, the MG preceded NMOSD (median interval: 16 years) and 11 of these had had a thymectomy although 1 only after NMOSD onset. In 4/5 patients tested, AQP4-Abs were detectable between 4 and 16 years prior to disease onset, including 2 patients with detectable AQP4-Abs prior to thymectomy. AChR-Abs decreased and the AQP4-Ab levels increased over time in concordance with the relevant disease. AChR-Abs were detectable at NMOSD onset in the one sample available from 1 of the 2 patients with NMOSD before MG.

CONCLUSIONS

Although both conditions are rare, the association of MG and NMOSD occurs much more frequently than by chance and the MG appears to follow a benign course. AChR-Abs or AQP4-Abs may be present years before onset of the relevant disease and the antibody titers against AQP4 and AChR tend to change in opposite directions. Although most cases had MG prior to NMOSD onset, and had undergone thymectomy, NMOSD can occur first and in patients who have not had their thymus removed.

Genetic engineering of Zymobacter palmae for production of ethanol from xylose

Its metabolic characteristics suggest that Zymobacter palmae gen. nov., sp. nov. could serve as a useful new ethanol-fermenting bacterium, but its biotechnological exploitation will require certain genetic modifications. We therefore engineered Z. palmae so as to broaden the range of its fermentable sugar substrates to include the pentose sugar xylose. The Escherichia coli genes encoding the xylose catabolic enzymes xylose isomerase, xylulokinase, transaldolase, and transketolase were introduced into Z. palmae, where their expression was driven by the Zymomonas mobilis glyceraldehyde-3-phosphate dehydrogenase promoter. When cultured with 40 g/liter xylose, the recombinant Z. palmae strain was able to ferment 16.4 g/liter xylose within 5 days, producing 91% of the theoretical yield of ethanol with no accumulation of organic acids as metabolic by-products. Notably, xylose acclimation enhanced both the expression of xylose catabolic enzymes and the rate of xylose uptake into recombinant Z. palmae, which enabled the acclimated organism to completely and simultaneously ferment a mixture of 40 g/liter glucose and 40 g/liter xylose within 8 h, producing 95% of the theoretical yield of ethanol. Thus, efficient fermentation of a mixture of glucose and xylose to ethanol can be accomplished by using Z. palmae expressing E. coli xylose catabolic enzymes.

Ethanol production from cellobiose by Zymobacter palmae carrying the Ruminocuccus albus β-glucosidase gene

Its metabolic characteristics suggest Zymobacter palmae gen. nov., sp. nov. could serve as a useful new ethanol-fermenting bacterium, but its biotechnological exploitation would require certain genetic improvements. We therefore established a method for transforming Z. palmae using the broad-host vector plasmids pRK290, pMFY31 and pMFY40 as a source of transforming DNA. Using electroporation, the frequency of transformation was 10(5) to 10(6) transformants/mug of DNA. To confer the ability to ferment cellobiose, which is a hydrolysis product from cellulosic materials treated enzymatically or with acid, the beta-glucosidase gene from Ruminococcus albus was introduced into Z. palmae, where its expression was driven by its endogenous promoter. About 56% of the enzyme expressed was localized on the cell-surface or in the periplasm. The recombinant Z. palmae could ferment 2% cellobiose to ethanol, producing 95% of the theoretical yield with no accumulation of organic acids as metabolic by-products. Thus, expression of beta-glucosidase in Z. palmae expanded the substrate spectrum of the strain, enabling ethanol production from cellulosic materials.

In vitro infection of host roots by differentiated calli of the parasitic plant Orobanche

Root parasites of the genus Orobanche are serious weeds in agriculture. An aseptic infection system of host roots using calli of three Orobanche species was developed for the study of host-parasite interaction. The response of calli to various hormonal combinations was studied, because a requirement for infection is the differentiation of root-like protrusions, which are capable of producing haustorial connections to the host. Infectious root-like protrusions develop under the influence of 0.5-1.0 mg l(-1) IAA, and under the combination of 0.2 mg l(-1) NAA with 5.0 mg l(-1) kinetin. These protocols produced root protrusions with pad-like structures that resembled attachment organs of Orobanche seedlings, and proved effective in parasitizing host roots. Direct contact with the medium inhibited haustorium development and prevented infection. To overcome this problem, certain root portions were isolated from the medium by inserting thin glass plates underneath. Calli were then placed on the raised root portions and successfully infected the roots and developed young Orobanche tubercles with vascular system that directly connected to the host.

The Ca(2+)-ATPase of the scallop sarcoplasmic reticulum is of a cold-adapted type

At 0 to 20 degrees C, the Ca(2+)-ATPase activity of the scallop sarcoplasmic reticulum (SR) was observed to be 7-60% of the peak activity at 30 degrees C, while the ATPase activity of the rabbit SR was 0-7% of its peak at 55 degrees C. The relative rabbit ATPase activity (0.7-7.0%) at 7-20 degrees C became higher (6-15 times) and lower (1/4-1/2), respectively, by the solubilization of the rabbit ATPase with a detergent, dodecyloctaethylenglycol monoether, and by the reconstitution of the ATPase with asolectin (soybean lecithin). No activity at 0 degrees C remained irrespective of these treatments. The relative scallop ATPase activity at 0-20 degrees C was, however, scarcely affected by such solubilization and reconstitution. In contrast to the rabbit ATPase, the scallop ATPase seems to be capable of operating independently without the help of the membrane lipid at low temperature.

Bone induction in subcutaneous tissue in rats by a newly developed DNA-coated atelocollagen and bone morphogenetic protein

A unique biomaterial, a mixture of DNA and collagen (DNA/collagen), was developed and its efficacy as a carrier matrix for bone morphogenetic protein (BMP) was evaluated histologically. The material was prepared as a composite of DNA from salmon milt and pepsin-digested type I collagen (atelocollagen) from bovine dermis. Phase-contrast and fluorescence microscopy showed atelocollagen fibres with DNA coating. The dose-response and time-course of bone induction by BMP in DNA/collagen (5 x 10 x 1 mm) in the subcutaneous tissue was investigated in 20 male Wistar rats. The BMP/DNA/collagen induced new bone in a dose-dependent manner (0, 25, 50 or 100 micrograms of BMP). Histological examination in the time-course study showed that the BMP (100 micrograms)/DNA/collagen induced bone formation, while the DNA/collagen alone resulted in the accumulation of fibroblasts. These results indicate that the DNA/collagen is effective as a carrier matrix for BMP. It provides a cell anchorage for differentiation of osteoblasts and is absorbed as bone matures.

Identification of novel nonmethylene-interrupted fatty acids, 7E,13E-20:2, 7E,13E,17Z-20:3, 9E,15E,19Z-22:3, and 4Z,9E,15E,19Z-22:4, in Ophiuroidea (brittle star) lipids

Fatty acids of Ophiuroidea (brittle star) Ophiura sarsi have been investigated by gas-liquid chromatography (GLC). About 2-13% of four unidentified fatty acids were found in total fatty acids from a sample caught at a depth of 1,100 m. Structural analyses were undertaken after partial hydrogenation of their concentrates with hydrazine hydrate and subsequent isolation of the monoenoate products by argentation thin-layer chromatography. The structures of the unidentified fatty acids were determined as 7E,13E-eicosadienoic (20:2), 7E,13E,17Z-eicosatrienoic (20:3), 9E,15E,19Z-docosatrienoic (22:3), and 4Z,9E,15E,19Z-docosatetraenoic (22:4) acids by gas chromatography-mass spectrometry of dimethyl disulfide adducts and GLC of the monoenoates on a polar column. These fatty acids belong to a family of nonmethylene-interrupted (NMI) polyunsaturated fatty acids frequently observed in marine invertebrates and conifer seeds. As far as the authors know, however, these NMI fatty acid types with mixed geometry of ethylenic bonds have not been reported previously.

A case of influenza subtype A virus-induced fulminant myocarditis: an experience of percutaneous cardio-pulmonary support (PCPS) treatment and immunohistochemical analysis

A 64-year-old man was admitted to the emergency center of Furukawa City Hospital because of common cold-like symptoms and hypotension. He was diagnosed as fulminant myocarditis with cardiogenic shock and arrhythmia elicited by influenza virus subtype A. Cardiac angiography, echocardiography and biopsy also showed myocarditis, and serum antibody titer to influenza virus subtype A was increased to 4-fold in paired serums. Treatments of both percutaneous cardio-pulmonary support (PCPS) and intra-aortic balloon pumping (IABP) were carried out to sustain the general circulation. PCPS treatment was discontinued on the 25th day of the admission, but IABP was continued. Finally, he died of multiple organ failure. The autopsy revealed myocardial necrosis with a slight fibrosis and a small amount of lymphocytic infiltration into the ventricular wall, which were compatible with restrictive myocarditis. Moreover, immunohistochemical analysis also showed the presence of viral antigens in cardiac myocytes. This case clearly showed that PCPS and IABP can be beneficial to sustain the general circulation in fulminant myocarditis, but cardiac pumping function failed completely to recover from myocardial damage.

Separation of sympathomimetic amines of abuse and related compounds by micellar electrokinetic chromatography

Separation of twelve sympathomimetic amines and related compounds by micellar electrokinetic chromatography (MEKC) with UV absorbance detection is described. These amines were well separated within 25 min using 50 mM sodium tetraborate solution containing 15 mM sodium dodecylsulfate (SDS) of pH 9.3 as a running solution and detected at 210 nm. MEKC was performed with an applied voltage of 13 kV at 25 degrees C using a fused-silica capillary (50 cm x 75 mm i.d.) with effective length of 37.5 cm. The detection limits of these compounds were in the range from 4 to 97 fmol/injection at a signal-to-noise ratio (S/N) of 3. The reproducibility of the method expressed as relative standard deviation (RSD) for within-day (n=6) and between-day (n=5) assays was less than 4.8 and 8.8%, respectively. The proposed method could be applied to the determination of an anorectic drug, phentermine, in Chinese tea with a detection limit of 99 microg/g (105 fmol/injection, S/N=3).