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The ionising interactions of high-energy particles with molecules have applications in many areas. Despite this, some areas, including positron scattering, lack experimental data due to difficulties in performing experiments. Here, quick and simple methods for computing direct electron and positron impact ionisation cross sections are presented. These calculations, performed using the open-source software RAPID-CS, can provide a complete data set as a first approximation for when experimental, or more detailed computational work is not available. The cross-sectional data set includes the total, partial/fragment-specific, single-differential, average secondary electron energy and stopping power cross sections. The molecules N 2 , O 2 and CO were chosen to study due to the availability of positron scattering data. An overall good agreement with experimental and other computational results is presented. Direct electron (left) and positron right) impact partial ionisation cross sections for N2. Total cross section: red, N 2 + partial cross section: blue, N + partial cross section: green.electron: solid lines: BEB, experimental measurements by Lindsay and Mangan [36]:Ürosses, Straub et al. [37]: stars, Opel et al. [39]: squares. Positron: solid lines: BEB0, Dashed lines: BEBA, Marler and Surko [23]: red crosses, Bluhme et al. [24]: stars [ABSTRACT FROM AUTHOR]

Folate deficiency has been associated with age-related neurodegeneration. One direct consequence of folate deficiency is a decline in the major methyl donor, S-adenosyl methionine (SAM). We demonstrate herein that pro-oxidant stress and dietary folate deficiency decreased levels of acetylcholine and impaired cognitive performance to various degrees in normal adult mice (9-12months of age, adult mice heterozygously lacking 5′,10′-methylene tetrahydrofolate reductase, homozygously lacking apolipoprotein E, or expressing human ApoE2, E3 or E4, and aged (2 - 2.5 year old) normal mice. Dietary supplementation with SAM in the absence of folate restored acetylcholine levels and cognitive performance to respective levels observed in the presence of folate. Increased aggressive behavior was observed among some but not all genotypes when maintained on the deficient diet, and was eliminated in all cases supplementation with SAM. Folate deficiency decreased levels of choline and N-methyl nicotinamine, while dietary supplementation with SAM increased methylation of nicotinamide to generate N-methyl nicotinamide and restored choline levels within brain tissue. Since N-methyl nicotinamide inhibits choline transport out of the central nervous system, and choline is utilized as an alternative methyl donor, these latter findings suggest that SAM may maintain acetylcholine levels in part by maintaining availability of choline. These findings suggest that dietary supplementation with SAM represents a useful therapeutic approach for age-related neurodegeneration which may augment pharmacological approaches to maintain acetylcholine levels, in particular during dietary or genetic compromise in folate usage. [ABSTRACT FROM AUTHOR]

An optical diagnostic system is designed and constructed for imaging a free mercury jet interacting with a high intensity proton beam in a pulsed high-field solenoid magnet. The optical imaging system employs a backilluminated, laser shadow photography technique. Object illumination and image capture are transmitted through radiation-hard multimode optical fibers and flexible coherent imaging fibers. A retroreflected illumination design allows the entire passive imaging system to fit inside the bore of the solenoid magnet. A sequence of synchronized short laser light pulses are used to freeze the transient events, and the images are recorded by several high speed charge coupled devices. Quantitative and qualitative data analysis using image processing based on probability approach is described. The characteristics of free mercury jet as a high power target for beam-jet interaction at various levels of the magnetic induction field is reported in this paper. [ABSTRACT FROM AUTHOR]

We describe collection and purification of peripheral blood CD34+ cells from volunteer, normal donors and allogeneic stem cell donors. A total of 98 aphereses were performed on 68 volunteer donors using peripheral venous access. The mean number of nucleated cells collected was 4.6 × 1010 which included 1.9 × 108CD34+ cells corresponding to 2.7 × 106 CD34+ cells/kg. The number of CD34+ cells collected did not differ between males and females but did correlate with the donor’s weight and the total number of nucleated cells collected. The Nexell Isolex 300i cell separator was used to isolate CD34+ cells from 30 of the collections. A mean of 0.36% of the total cells was recovered and included 43 ± 18% of the CD34+ cells. CD34+ cells represented 85 ± 11% of the recovered cells. The total number of CD34+ cells recovered was not influenced by the number of nucleated cells placed on the Isolex 300i. The percentage of CD34+ cells recovered was not related to the number of CD34+ cells placed on the Isolex 300i. The purity of the final product was influenced by the number of CD34+ cells but not the total number of nucleated cells. An additional 38 CD34+ cell isolations were performed on normal allogeneic stem cell donors with similar results. These observations further support the safety and feasibility of peripheral blood CD34+ cell collection and purification. Bone Marrow Transplantation (2000) 26, 1271–1279. [ABSTRACT FROM AUTHOR]

In the use of autologous PBPC transplantation in patients with multiple myeloma, contamination of PBPC with myeloma cells is commonly observed. Enrichment for CD34+ cells has been employed as a method of reducing this contamination. In this study the reduction of myeloma cells in PBPC was accomplished by the positive selection of CD34+ cells using immunomagnetic bead separation (Isolex 300 system). PBPC were mobilized from 18 patients using cyclophosphamide (4.5 g/m2) and G-CSF (10 μg/kg/day). A median of two leukaphereses and one selection was performed per patient. The median number of mononuclear cells processed was 3.50 × 1010 with a recovery of 1.11 × 108 cells after selection. The median recovery of CD34+ cells was 48% (range 17–78) and purity was 90% (29–99). The median log depletion of CD19+ cells was 3.0. IgH rearrangement, assessed by PCR, was undetectable in 13 of 24 evaluable CD34+ enriched products. Patients received 200 mg/m2 of melphalan followed by the infusion of a median of 2.91 × 106/kg CD34+ cells (1.00–16.30). The median time to absolute neutrophil count >0.5 × 109/l was 11 days, and sustained platelet recovery of >20 × 109/l was 14 days. We conclude that immunomagnetic-based enrichment of CD34+ cells results in a marked reduction in myeloma cells without affecting engraftment kinetics. [ABSTRACT FROM AUTHOR]

A new guidewire constructed from kink-resistant titanium-nickel alloy, polyurethane, and hydrophilic polymer is described. We have used this wire in 119 angiographic and 49 interventional procedures without complications. In numerous applications, it offers significant advantages over other guidewires. It is particularly helpful for angiography and interventional procedures requiring catheterization through markedly tortuous vessels, tight stenoses, or occlusions. [ABSTRACT FROM AUTHOR]

A 20-year-old African American woman with sickle cell disease (HbSS) was found unresponsive possibly because of an accidental overdose of morphine used to control a painful crisis. She was transferred to our facility with acute renal failure and shock liver. She immediately required intubation for low oxygen saturation and dopamine support for hypotension. Laboratory values were as follows: Hb, 6 g per dL; Hct, 16.6 percent; PLTs, 117 x 109per L;WBCs, 26.1 x 109per L; myelocytes, 2 percent; metamyelocytes, 1 percent; bands, 14 percent; neutrophils,60 percent; lymphocytes, 21 percent; basophils, 2 percent; HbS, 78 percent; haptoglobin,<6 mg per dL (normal, 30-200); PT, 23.1 sec (normal, 10.8-13.7); PTT, 39.5 sec (normal, 24.7-33.4); INR, 2.09 (normal, 0.9-1.1); total bilirubin,16.1 mg per dL(normal, 0-1); LDH, 31,860 units per L (normal, 265-580); BUN, 43 mg per dL (normal, 5-20); creatinine,2.5 mg per dL (normal, 0.6-1.4); ALT, 2373 units per L (normal, 0-50); AST, 5727 units per L (normal, 25-45);amylase, 2002 units per L (normal, 25-115); and lipase, 16,091 units per L (normal, 25-110).An emergent one-plasma-volume exchange (3.6 L) was performed with FFP as the replacement fluid. Theintent was to efficiently lower levels of inflammatory mediators, bilirubin, and pancreatic enzymes (which may have a detrimental effect on the replacement RBCs); correct mild coagulopathy and acidosis; and possibly prevent acute renal failure. The latter goal was not realized and the patient required hemodialysis for several weeks. The plasma removed appeared murky brown or "muddy" owing to gross hemolysis and presumed lipemia. The plasma exchange was immediately followed by a total RBC exchange transfusion of 2.3 L. The replacement RBCs were HbS negative, less than 10 days old, leukoreduced, and phenotypically matched for Rh and K antigens. She tolerated both procedures well and vital signs remained stable (initial, BP 100/56, HR 119; after, BP 98/47, HR 126). Her HbS was reduced to 19.9 percent and LDH to 5060 units per L after exchange. She was extubated 3 days after these exchanges and recovered sufficiently from multiorgan failure and a pancreatic abscess for discharge after 5 weeks of intensive treatment. [ABSTRACT FROM AUTHOR]