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Momentum distributions associated with ortho-positronium (o-Ps) pick-off annihilation photon are often influenced by light elements, as, e.g., carbon, oxygen, and fluorine. This phenomenon, so-called element specificity of o-Ps pick-off annihilation, has been utilized for studying the elemental environment around the open spaces. To gain an insight into the element specificity of o-Ps pick-off annihilation, the chemical shift of oxygen 1s binding energy and the momentum distributions associated with o-Ps pick-off annihilation were systematically investigated for alkali-metal loaded SiO2 glasses by means of X-ray photoelectron spectroscopy and positron-age-momentum correlation spectroscopy, respectively. Alkali metals introduced into the open spaces surrounded by oxygen atoms cause charge transfer from alkali metals to oxygen atoms, leading to the lower chemical shift for the oxygen 1s binding energy. The momentum distribution of o-Ps localized into the open spaces is found to be closely correlated with the oxygen 1s chemical shift. This correlation with the deepest 1s energy level evidences that the element specificity of o-Ps originates from pick-off annihilation with orbital electrons, i.e., dominantly with oxygen 2p valence electrons and s electrons with lower probability. [ABSTRACT FROM AUTHOR]

Investigates the interpersonal constructs of student nurses during a clinical practice training course in a hospital using the Doll Location Test. Dyadic distances from the self to peers and to patients; Development of cohesive feelings to sick persons during the period of clinical practice; Validity of traditional evaluation by supervisors.

Individual adult Perkinsiella saccharicida reared on sugarcane infected with Fiji disease virus (FDV) were confined on healthy plants for 7 days to test for virus transmission and were then sacrificed and assayed for the presence of FDV-specific structures by immunoelectron microscopy. Only 15% of the insects contained FDV antigens and 6% transmitted the virus. FDV-specific antigens were detected in individual planthoppers by immuno-osmophoretic and enzyme-linked immunosorbent assays about as efficiently as by immunoelectron microscopy. The possible reasons for the inefficient acquisition and transmission of FDV by P. saccharida are discussed. [ABSTRACT FROM AUTHOR]

The article is concerned with the isolation and identification of tomato ringspot virus from diseased Pentas lanceolata in South Australia. Virus was transmitted from P. lanceolata showing disease symptoms by mechanical inoculation using leaf extracts prepared in tap water or 0.1 M phosphate buffer, pH 7, to Nicotiana clevelandii A. Gray or cucumber (Cucumis sativus L.). Symptoms on N. clevelandii consisted of local necrotic ringspots on the inoculated leaves and systemic mosaic. On the cucumber seedlings, the virus produced chlorotic lesions on the inoculated cotyledons and a mosaic on systemically infected leaves.

A new virus, subterranean clover mottle virus (SCMoV) was found at several locations m Western Australia in Trifolium subterraneum L. (subterranean clover) with severe disease symptoms. Particles of the virus were shown to share many physical properties with members of the sobemovirus group. However, in addition to the single-stranded RNA of Mr about 1.5 ⊗ 106 which is characteristic of sobemoviruses, SCMoV particles also contained circular and linear viroid-like RNAs of two size classes, one about 400 and the other about 300 nucleotides long. At present it is not clear if the two types of viroid-like RNAs are components of the same SCMoV strain or of closely), related strains of the virus which are able to coinfect subterranean clover. SCMoV was shown to be serologically related to lucerne transient streak virus (LTSV). However, the relationship was remote and whereas most high-titred antisera to LTSV reacted with SCMoV particles, antisera to SCMoV failed to recognize those of LTSV. Neither SCMoV nor LTSV are serologically related to velvet tobacco mottle virus (VTMoV) or Solanum nodiflorum mottle virus (SNMV). However, particles of all four viruses have many physical and chemical properties in common, including RNA complements consisting of both virus-like and viroid-like RNAs. Because of their affinities and unique RNA complements, we suggest that SCMoV, LTSV, VTMoV and SNMV may warrant inclusion in a new taxonomic group. [ABSTRACT FROM AUTHOR]

In mammals, three ras genes, H-ras, N-ras and K-ras, encode homologous but distinct 21-kDa Ras proteins. We examined the in vivo functional relationship of the three ras genes in mouse embryonic development by investigating the phenotypes of mice deficient in one or multiple ras genes. H-ras−/− mice and N-ras−/− mice as well as a substantial proportion of H-ras−/−/N-ras−/− mice expressing only the K-ras gene were viable, while K-ras−/− mice were embryonically lethal, as have been reported previously. N-ras−/−/K-ras+/− mice died neonatally, while H-ras−/−/K-ras−/− embryos died much earlier than K-ras homozygous mutant fetuses. To further investigate the functional relationship of the ras genes in embryonic development, we introduced a human H-ras transgene into single or multiple ras mutant mice and found that the transgene rescued mice, including triple ras mutants, from embryonic lethality in association with correction of thin ventricular walls of the heart in null K-ras mutant mice. In situ hybridization revealed that the expression of the H-ras transgene on embryonic day E13.5 and E15.5 was more intense in major organs, including the heart, than those of endogenous ras genes. We therefore conclude that the functions of the ras genes are partially overlapping in mouse embryonic development.Oncogene (2008) 27, 2961–2968; doi:10.1038/sj.onc.1210956; published online 3 December 2007 [ABSTRACT FROM AUTHOR]

Anti-glomerular basement membrane (anti-GBM)-induced glomerulonephritis involves T-helper type 1 (Th1) responses leading to rapid crescent formation. As many inflammatory and immune responses in general are affected by histamine, we examined the effects of histaminergic ligands on immune renal injury in the rat. Female Wistar-Kyoto rats were injected intraperitoneally with an antibody against the GBMs. Histaminergic ligands were then injected twice daily for 5 days after which renal function was assessed by proteinuria. Treatment with histamine led to significant dose-dependent reductions in proteinuria compared to the control antibody-injected group and markedly decreased the number of crescentic glomeruli and macrophage infiltration of the glomeruli. Furthermore, histamine significantly decreased the plasma concentration of interleukin-12, a Th1-type cytokine compared to the antibody-injected control animals. Dimaprit, an H2/H4 agonist, mimicked the effects of histamine on proteinuria and crescent formation. Clozapine, an H4 agonist, tended to mimic the effects of histamine, whereas an H1, mepyramine, or an H2 antagonist, ranitidine, did not reverse the protective effect of histamine. We suggest that histamine may alleviate renal injury in anti-GBM glomerulonephritis by suppressing the immune response.Kidney International (2007) 72, 608–613; doi:10.1038/sj.ki.5002370; published online 13 June 2007 [ABSTRACT FROM AUTHOR]

Abstract: We performed a comparative experiment to investigate: (1) how the ubiquitous soil bacterium Bacillus subtilis weathers granite; and (2) which granite-forming minerals weather more rapidly via biological processes. Batch system experiments (granite specimen in a 500 ml solution including NaCl, glucose, yeast extract and bacteria B. subtilis at 27 °C) were carried out for 30 days. Granite surfaces were observed by SEM before and after the experiment. B. subtilis had a strong influence on granite weathering by forming pits. There were 2.4 times as many pits and micropores were 2.3 times wider in granite exposed to B. subtilis when compared with bacteria-free samples. B. subtilis appear to preferentially select an optimum place to adhere to the mineral and dissolve essential elements from the mineral to live. Plagioclase was more vulnerable to bacterial weathering than biotite among the granite composing minerals. [Copyright &y& Elsevier]

We quantitatively investigated the change in nitric oxide (NO) in the hypothalamic paraventricular nucleus (PVN) and its effect on cardiovascular regulation during shaker stress (SS) using brain microdialysis in awake rats. Male Wistar rats were fed either NG-nitro-L-arginine methyl ester (L-NAME, 0.7 g/L) or tap water for 2 weeks. Two days after implantation of an arterial catheter and guide shaft, a microdialysis probe was placed to perfuse the PVN with degassed Ringer solution at 2 μl/min in awake normotensive Wistar (CONTROL) and chronic L-NAME-treated hypertensive rats. After the rat was placed in a plastic cage set on a shaker, the blood pressure and heart rate was monitored and 10-min SS was loaded at a frequency of 200 cycles/min. Dialysate samples were analyzed by NO analyzer (based on the Griess reaction) every 10 min, and NOx (NO2− + NO3−) was measured. Plasma NOx was also measured before and after SS. Pressor responses elicited by SS were significantly greater in L-NAME-treated rats than in the CONTROL. Although NOx in the PVN dialysate were increased by SS in the CONTROL, these responses were attenuated in chronic L-NAME-treated rats. Resting plasma NOx were higher in the CONTROL than in L-NAME-treated rats. SS elicited no difference between two groups in plasma NOx. These results indicated that NO within the PVN, but not in systemic circulation, may play a role on the attenuation of the pressor responses elicited by SS. The dysfunction of NO release within the PVN may, in part, play a role in the exaggerated pressor responses in acute environmental stress. [Copyright &y& Elsevier]

Describes a case of sustained-release diltiazem overdose which showed excellent efficacy of gastrointestinal decontamination in hypertension patients. Case history of the patient; Treatment of diltiazem overdose; Patient's clinical course.