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B Arbogast

Publications and source records attributed to B Arbogast.

18 recordsLinked to original sources
PubMed1992

Determination of the glycosylation patterns, disulfide linkages, and protein heterogeneities of baculovirus-expressed mouse interleukin-3 by mass spectrometry.

The primary structure of mouse interleukin-3 (IL-3) expressed by recombinant baculovirus-infected silkworm (Bombyx mori) larvae was analyzed by subjecting isolated IL-3 derived peptides to liquid secondary ion mass spectrometry. Two species of IL-3 were isolated from the silkworm hemolymph by reverse-phase high-pressure liquid chromatography. The major component has M(r)20-22 x 10(3) as determined by SDS-PAGE. Liquid secondary ion mass spectrometric analysis was carried out on the reduced tryptic and endopeptidase lysyl-C peptides of glycosylated and deglycosylated IL-3. These studies provided evidence that (1) Asn-16 is heterogeneously glycosylated with four different oligosaccharides, (2) Asn-86 is either nonglycosylated or has attached to it one oligosaccharide, (3) the N-glycosylation sites Asn-44 and Asn-51 are not glycosylated, and (4) there is no O-glycosylation. Liquid secondary ion mass spectrometric analysis of the unreduced tryptic peptides provided evidence for disulfide linkages between Cys-140 and Cys-79 or Cys-80 and between Cys-17 and Cys-79 or Cys-80. In comparison to the major component, a minor IL-3 species (M(r) 17-19 x 10(3) by SDS-PAGE) isolated from the hemolymph showed no difference with respect to the glycosylation pattern or the disulfide linkages, but it was cleaved between Ala-127 and Ser-128, and only a disulfide linkage between Cys-140 and Cys-79 or Cys-80 held the molecule together.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1989

Evidence for radical anion formation during liquid secondary ion mass spectrometry analysis of oligonucleotides and synthetic oligomeric analogues: a deconvolution algorithm for molecular ion region clusters.

It is shown that one-electron reduction is a common process that occurs in negative ion liquid secondary ion mass spectrometry (LSIMS) of oligonucleotides and synthetic oligonucleosides and that this process is in competition with proton loss. Deconvolution of the molecular anion cluster reveals contributions from (M-2H).-, (M-H)-, M.-, and (M + H)-. A model based on these ionic species gives excellent agreement with the experimental data. A correlation between the concentration of species arising via one-electron reduction [M.- and (M + H)-] and the electron affinity of the matrix has been demonstrated. The relative intensity of M.- is mass-dependent; this is rationalized on the basis of base-stacking. Base sequence ion formation is theorized to arise from M.- radical anion among other possible pathways.

Algorithms↗
PubMed1984

Acute radiation injury of mice and the influence of sudden time shift.

The daily light-dark regimen for two groups of mice was advanced by 8 hr. A third group remained in unchanged lighting conditions. At seven different times within the following day subgroups of the time-shifted mice as well as of the group with unchanged time schedule were exposed to whole-body X irradiation. Mortality, body weight, and temperature of each animal were registered for 30 days following exposure and were regarded as indicators of radiation response. Radioresistance was found to be highest after two-thirds of the daily light span, confirming earlier reports by other authors. Well-defined effects of time shift and a corresponding shift of the maximum of radioresistance could be demonstrated. With the individual body weight as an independent variable, mathematical formulas for survival prognosis could be established.

Animals↗
PubMed1979

The determination of polychlorodibenzo-p-dioxins in pentachlorophenol and wood treatment solutions.

Analytical methods have been implemented to measure levels of polychlorodibenzo-p-dioxins, and polychlorodibenzofurans in pentachlorophenol solutions used in the Boulton wood treatment process. When normalized against the pentachlorophenol (PCP) content, the octachlorodibenzo-p-dioxin level was 34% higher in the recirculating PCP solution than in the fresh PCP solution, and in the sludge it was 90% higher. A smaller concentration increase was observed for the heptachlorodibenzo-p-dioxin in the recirculating solution, but a similar increase was observed in the sludge.

Chlorophenols↗
PubMed1977

Methylmercury: effect on serum enzymes and humoral antibody.

Dosages of 20 and 10 ppm methylmercury were toxic to rabbits while 1 ppm did not produce clinical signs or death. Serum alkaline phosphatase levels were elevated in all rabbits exposed to methylmercury. Methylmercury-exposed rabbits challenged to A/PR8 influenza virus had hemagglutination inhibition titers as much as four times lower than those of controls. Histopathologic lesions were found in the cerebellum of rabbits that died. The most significant features of this study were that methylmercury chloride suppressed the humoral immune system and resulted in increased serum alkaline phosphatase levels, which may aid in diagnosis when methylmercury poisoning is suspected.

Alkaline Phosphatase↗
PubMed1976

Rat parietal yolk sac basement membrane. An investigation of the antigenic determinants using a radioimmunoassay.

Previous studies have shown that there is microscopic and biochemical evidence that rat parietal yolk sac synthesizes basement membrane (type IV) collagen; this study shows that a radioimmunoassay may be used for the detection of type IV collagen in such biosynthetic systems. Rat parietal yolk sacs incubated in medium containing (14C) proline either with or without alphaalpha-dipyridyl produced either unhydroxylated or hydroxylated (14C)collagen. The immunological reactivity of these two preparations was investigated using antibodies to bovine type IV collagen in a radioimmunoassay which demonstrated that the hydroxylated (14C)collagen preparation had a considerably higher level of antigenicity than the unhydroxylated (14C)collagen. Hydroxylated rat type IV (14C)collagen which had been reduced and alkylated was intermediate in antigenicity between hydroxylated and unhydroxylated material. These findings suggest that there are antigenic determinants which depend upon hydroxylation of the collagen molecule, and others dependent upon intact disulphide bonds. In addition, various levels of pepsin extracted unlabelled calf anterior lens capsule collagen caused inhibition of antibody binding to (14C)collagen. Rat type IV (14C)collagen which had been digested with collagenase was inactive in the radioimmunoassay, while pepsin digestion caused no reduction in antigenicity. These findings suggest that the antiserum is directed towards the collagenous part of the molecule and may be a useful tool in the detection of biosynthesized basement membrane collagen.

Alkylation↗
PubMedDate not supplied

Aspirin improves the patency rate of seeded vena cava grafts.

The purpose of this study was to evaluate the effectiveness of aspirin (ASA) and porcine endothelial cell seeding in improving the patency rate of vena cava grafts. Thirty-nine dogs underwent infrarenal vena cava replacement by 10 cm lengths of 8 mm I.D. ringed polytetrafluoroethylene grafts. Thirty-one grafts were seeded with 1-1.5 x 10(6) porcine aortic endothelial cells while eight were not (GIII). Of the seeded group, 16 animals received no ASA (GI), while 15 others (GII) were given ASA (325 mg) daily starting two days preoperatively and continuing until sacrifice. Venograms were performed on the fourth postoperative day. Grafts were harvested 32 days after insertion and evaluated for patency rate and endothelialized surfaces. The 32-day patency rate was significantly higher for GII than for GI and III animals (67% vs. 13 and 25% respectively). Endothelialized surface was higher in GII than Gi and III (67% vs. 16% and 18% respectively). We conclude that endothelial cell seeding alone does not prevent graft closure and that a combination of ASA and cell seeding significantly increases the patency rate of vena cava grafts.

Animals↗
PubMedDate not supplied

Effect of preclotting and precoating agents on seeded venous grafts.

This study evaluated the effect of whole blood preclotting (WB), fibronectin (FB) and "Cell Tak" (CT) precoating on the patency rate of seeded vena cava grafts. Ten cm x 8 mm ID ringed PTFE grafts were implanted in the vena-cavae of 29 dogs. Aspirin (325 mg po qd) was administered pre-operatively and continued post-operatively. After preclotting or precoating, all grafts were seeded with porcine endothelial cells. The 32 day patency rates were: 67%, 67% and 37% for WB, FB and CT, respectively (p less than 0.5 CT vs FB, WB). Endothelialized surfaces ranged from 67 +/- 35, 43 +/- 41 to 28 +/- 45% respectively for WB, FB and CT (p less than 0.05 CT vs WB). Preclotting time was shortest for WB technique. We conclude that: 1) FB and WB grafts have the highest patency rate with WB preclotting being a more cost effective and less time consuming technique; 2) endothelial seeding and Aspirin may make vena cava grafting possible.

Animals↗
PubMedDate not supplied

Chronobiologic serial sections of several orders.

The chronobiologic serial section is described. Its applicability to the analysis of nonequidistant data is emphasized. Its ability to detect and quantify multiple components is discussed and exemplified on simulated series with various amounts of additive Gaussian noise. This least-squares method is discussed in the context of a number of complementary procedures such as complex demodulation and linear-nonlinear least-squares rhythmometry.

Animals↗