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Notes: One of the lay public's concerns about genetically modified (GM) organisms (GMO) and related emerging technologies is that not all the important risks are evaluated or even identified yet—and that ignorance of the unanticipated risks could lead to severe environmental or public health consequences. To some degree, even the scientists who participated in the analysis of the risks from GMOs (arguably the people most qualified to critique these analyses) share some of this concern. To formally explore the uncertainty in the risk assessment of a GM crop, we conducted detailed interviews of seven leading experts on GM oilseed crops to obtain qualitative and quantitative information on their understanding of the uncertainties associated with the risks to agriculture from GM oilseed crops (canola or rapeseed). The results of these elicitations revealed three issues of potential concern that are currently left outside the scope of risk assessments. These are (1) the potential loss of the agronomic and environmental benefits of glyphosate (a herbicide widely used in no-till agriculture) due to the combined problems of glyphosate-tolerant canola and wheat volunteer plants, (2) the growing problem of seed lot contamination, and (3) the potential market impacts. The elicitations also identified two areas where knowledge is insufficient. These are: the occurrence of hybridization between canola and wild relatives and the ability of the hybrids to perpetuate themselves in nature, and the fate of the herbicide-tolerance genes in soil and their interaction with soil microfauna and -flora. The methodological contribution of this work is a formal approach to analyzing the uncertainty surrounding complex problems.

Notes: Background: We present a new one-wire technique for balloon aortic valvuloplasty and discuss possible advantages of this technique over other techniques. Methods: The records of 16 patients who underwent 18 procedures were reviewed. Technique: A floppy-tipped, nitinol wire (Ultra-Select, Microvena Corp., White Bear Lake, MN) is placed across the aortic valve through a guide/measurement catheter positioned in the aortic root. The guide catheter is then removed, and the balloon catheter is positioned. Balloon dilation is then performed. Results: Predilation all patients had 0–1+ aortic insufficiency (AI). Four of 18 procedures resulted in an increase of 〉1 grade of AI, leaving 14 of 18 with ≤1 grade increase in AI. The mean gradient reduction achieved was 65%. Follow-up: Eighty-seven percent of the procedures have required no further intervention. Conclusion: The ease and simplicity of the procedure may reduce the risk of increasing AI, decrease fluoroscopy time, and arterial access time. (J Interven Cardiol 2004;17:17–19)

Notes: Objective:  To detect a possible allergen in a florist with occupational dermatitis. Patient and methods: a 27-year-old atopic female working in a greenhouse since 10 years presented with a 3 months history of severe eczema involving hands, face, eyelids and neck requiring a stop of the work. Tests were performed with European standard series (Trolab®), additional series, plant series, (Chemotechnique Diagnostics®) and flowers. Readings were performed at D2 and D3 according ICDRG criteria. Results: positive patch tests were parabens +/+ nickel sulphate ++/++ cobalt chloride −/++ palladium chloride ++/++ thiomersal ++/++, Iris petal ++/+. Then various colours of Iris were tested and pale blue, yellow and white petals were positive ++/++ but purple blue petal was negative. The proximal yellow part of purple blue petal and orange part of yellow petal were also positive ++/++. The leaf and pistil of Iris were negative. One control with a white Iris petal was negative. Then the patient presented flare up of her dermatitis in the presence of Iris, at home, without handling them, that could make suspect an airborne contact dermatitis. Even after examination by a botanist, the precise identificaton of these Iris was not possible. Positive patch tests to unspecified Iris (petal and leaf) have already been reported in a florist who was allergic to safflower (Van der Willigen A.H. and al, Contact Dermatitis, 1987, 17,184). Conclusion: this case could evoke the responsibility of anthocyans, which play a role in the colours, but essential oils or other components are also possible responsibles.

Notes: We describe a prototype linear vacuum-ultraviolet x-ray pinhole camera based on the luminescence of a phosphor screen working in reflection mode. The luminescence emitted by the phosphor, in response to radiation selected by a broadband filter, is detected using a 1024 pixel intensified linear array detector. By operating this detector with integration times from 20 to 50 ms, random plasma fluctuations can be smeared out, so that structures related to the magnetic topology can be searched for. © 2002 American Institute of Physics.

Notes: The interaction potential energy surface (PES) of H4 is of great importance for quantum chemistry as a test case for molecule–molecule interactions. It is also required for a detailed understanding of certain astrophysical processes, namely collisional excitation and dissociation of H2 in molecular clouds, at densities too low to be accessible experimentally. The 6101 ab initio H4 energies reported in 1991 by Boothroyd et al. demonstrated large inaccuracies in analytic H4 surfaces available at that time. Some undesirable features remained in the more accurate H4 surfaces fitted to these energies by Keogh and by Aguado et al., due in part to the relatively sparse coverage of the six-dimensional H4 conformation space afforded by the 6101 ab initio energies. To improve the coverage, 42 079 new ab initio H4 energies were calculated, using Buenker's multiple reference (single and) double excitation configuration interaction program. Here the lowest excited states were computed as well as the ground state, and energies for the original 6101 conformations were recomputed. The ab initio energies have an estimated rms "random" error of ∼0.5 millihartree and a systematic error of ∼1 millihartree (0.6 kcal/mol). A new analytical H4 PES was fitted to these 48 180 ab initio energies (and to an additional 13 367 points generated at large separations), yielding a significant improvement over previous H4 surfaces. This new PES has an rms error of 1.43 millihartree relative to these 48 180 ab initio energies (the fitting procedure used a reduced weight for high energies, yielding a weighted rms error of 1.15 millihartree for these 48 180 ab initio energies). For the 39 064 ab initio energies that lie below twice the H2 dissociation energy, the new PES has an rms error of 0.95 millihartree. These rms errors are comparable to the estimated error in the ab initio energies themselves. The new PES also fits the van der Waals well to an accuracy of about 5%. For relatively compact conformations (energies higher than the H2 dissociation energy), the conical intersection between the ground state and the first excited state is the largest source of error in the analytic surface. The position of this conical intersection forms a somewhat complicated three-dimensional hypersurface in the six-dimensional conformation space of H4. A large portion of the position of the conical intersection has been mapped out, but trying to include the conical intersection explicitly in an analytic surface is beyond the scope of the present paper. © 2002 American Institute of Physics.

Notes: Background:  Intratumor hypoxia has been shown to promote more aggressive and metastatic cancer phenotypes that are associated with treatment resistance and poor prognosis. Cellular proliferation and its control are known to be important components of tumor progression. Hypoxia induces cell-cycle arrest in cultured cell lines, possibly via up-regulation of the cyclin-dependent kinase inhibitor p27. The effect of hypoxia on cell-cycle regulation in excised human tumors has not been investigated.Methods:  We performed immunohistochemistry for p27 and Ki-67 on 10 formalin-fixed paraffin-embedded metastatic melanomas, selected on the basis of histological evidence of zonal/geographic necrosis, adjacent to areas with viable perivascular tumor cells.Results:  In the majority of cases, there was a significant increase in p27 staining in cells adjacent to necrotic areas compared to perivascular zones. An inverse staining pattern between Ki-67 and p27 was identified in these tumors. Tumors with no zonal increase in p27 staining demonstrated a diffuse pattern of staining for Ki-67 within tumor nests.Conclusions:  While increased cellular proliferation is a characteristic of cancer, subsets of human melanomas may retain the ability to regulate their rate of proliferation in response to changes in the tumor microenvironment. The hypoxia-mediated cell-cycle arrest (decreased Ki-67) in these tumors may be mediated by p27 up-regulation.

Notes: Background:  The introduction of the immunosuppressant cyclosporine has significantly improved renal transplant survival. It is an expensive drug and generic alternatives may offer cost advantages. However, generic alternatives must be shown to provide equivalent therapeutic efficacy and safety. This study reports our experience of a switch from the microemulsion formulation of cyclosporine, Neoral (Novartis), to the generic equivalent, Cysporin (Mayne Pharma).Method:  A two-period, single-sequence, cross-over study was done to compare cyclosporine blood levels and the area under the curve (AUC) of Neoral with Cysporin 2 weeks after a 1:1 dose switch. cyclosporine blood levels were measured at time points 0, 2, 4 and 8 h (C0, C2, C4, C8) after the switch. The cyclosporine AUC at 0–4 h and 0–12 h were calculated using the trapezoidal method. The two formulations were considered to result in equivalent blood levels if the 95% confidence interval (CI) of the ratio of the two levels was within 0.8–1.25.Results and Conclusion:  A total of 38 stable renal transplant patients aged 49.79 ± 11.38 years (mean ± SD), who were 7.84 ± 3.97 years postrenal transplantation, were studied. The Neoral dose at the time of the switch was 2.38 ± 1.21 mg per kg bodyweight. At all measured time points the 95% CI for the cyclosporine drug level ratio was between 0.9 and 1.15. There were no significant adverse events during the period of study. We conclude that the generic formulation of cylosporin, Cysporin, after a 1:1 switch from Neoral results in equivalent blood levels in stable renal transplant recipients. After switchover cyclosporine levels at C0 or C2 can continue to be monitored as per the institution's current monitoring practice.

Notes: Aims:  Differential diagnosis between multiple myeloma (MM), monoclonal gammopathy of uncertain significance (MGUS), and polyclonal plasmacytosis may be difficult in cases with not much bone marrow infiltration. Normal plasma cells express the antigens CD138, CD38, CD19, CD10 and D-related human leucocyte antigen (HLA-DR). Myelomatous plasma cells lack B lymphoid-associated markers and may express cell surface antigens associated with other haematopoietic lineages such as NCAM/CD56 (neural cell adhesion molecule). Recently, a monoclonal antibody, anti-CD56, has become available that can be used in fixed tissues embedded in paraffin, and it has been reported that osteoblastic cells of trabecular bone strongly express NCAM/CD56.Methods and results:  We analysed NCAM molecule expression in 35 samples from patients with plasma cell disorders: 14 cases of MM, 16 cases of MGUS, and five cases of polyclonal plasmacytosis using immunohistochemistry in parallel in bone marrow core biopsies processed routinely and in bone marrow smears from the same patients. Of the MM samples 78% were CD56+ in smears and 92% positive in biopsies. We did not find strong CD56 expression in MGUS samples. One of five samples of polyclonal plasmacytosis was CD56+. A case was considered to be positive for CD56 expression if 〉50% of the CD138+ plasma cells expressed NCAM with an intensity on a par with that of the osteoblasts.Conclusion:  We conclude that CD56 antibody is a very useful marker in the study of plasma cell proliferation in bone marrow biopsies and in bone marrow aspirates and is a great help in discriminating between MM, MGUS, and polyclonal plasmacytosis, especially in those cases with low infiltration.

Notes: [Auszug] Conditional or temperature-sensitive (TS) alleles represent useful tools with which to investigate gene function. Indeed, much of our understanding of yeast has relied on temperature-sensitive mutations which, when available, also provide important insights into other model systems. However, the ...

Notes: The effect of a localized SiO2 codoping on the conversion of polycrystalline, MgO-doped Al2O3 tubes to single-crystal sapphire was investigated. Codoping with SiO2 before sintering intentionally triggered abnormal grain growth, which resulted in the full conversion of tube surfaces to single crystal without adversely affecting densification to a almost pore-free, translucent state. The degree of surface conversion was strongly dependent on experimental variables, which included furnace temperature and codoping amount. Surface-converted tubes had excellent physical properties, which included good thermal cycling resistance and optical properties superior to unconverted, polycrystalline Al2O3.