Hb Sinai,a new α chain mutant a 47 His

Summary A new chain mutant Hb-Sinai ₄₇ ^His is described. The aminoacid composition of all tryptic peptides has been determined, with the exception of the insoluble core. In the fingerprint peptide T 6 which normally migrates between T 3 and T 1, moves now between T 3 and T 7. The aminoacid composition of peptide T 6 indicates a change in the aminoacid composition from Asp- to His⁺ in position 47.This work was supported by Grant No. GM 13714 U.S.P.H.S.     

Atrichum cylindricum (Polytrichaceae), an overlooked moss in the southeastern United States

The new combination,Atrichum cylindricum (Willd. ex Weber) G. Smith is made for a moss described in 1741 by Dillenius, based on a Clayton specimen from Virginia. This species, which has been overlooked by American bryologists, is now known from the southern Atlantic and Gulf coastal plain, and the Cumberland Plateau in eastern Tennessee.Atrichum undulatum var.attenuatum Bruch & Schimp. is a synonym. Illustrations of the species and a map of its distribution are included.     

Defluorination of fluoroacetate in the rat

Rats given 5 ppm F as FAc (equivalent to 26 ppm of NaFac) in the drinking water for approximately four months deposited as much fluoride in the skeletal system as did rats receiving 5 ppm F as NaF in the water. Little evidence could be found for the presence of organically bound fluoride in bone after ingesting FAc, though an appreciable proportion of skeletal fluoride deposited when NaF was ingested was shown not to respond to the fluoride ion electrode. The daily urinary excretion of total fluoride after FAc was somewhat greater than after NaF; about two thirds of this fluoride responded to the electrode, whereas more than 90 percent of the total fluoride after NaF was ionic in nature. The data are interpreted as showing that the rat is capable of splitting the C-F bond in FAc and/or in its fluoride-containing metabolites, with subsequent skeletal storage and renal excretion of the released fluoride ion. The chronic administration of this low level of FAc caused an early but temporary retardation of growth. The Krebs cycle was interfered with, as evidenced by increased concentrations of citrate in the kidney and urine. At termination of the experiment, histological examination of the testes showed that the FAc had induced severe damage characterized by massive disorganization of the tubules, nearly total loss of functional cells, absence of sperm, and damage to the Sertoli cells.     

The in vitro unscheduled DNA synthesis (UDS) assay in rat primary hepatocytes: evaluation of 2-furoic acid and 7 drug candidates

The in vitro unscheduled DNA synthesis assay (UDS) is part of the routine genetic toxicology screening at The Upjohn Company. The purpose of this paper is to report results for 8 compounds which were tested in the in-house genetic toxicology program. These compounds represent diverse chemical structure and most of them entered the screening program because they are biologically active in efficacy screens. All tests were carried out under Good Laboratory Practices Regulations of the U.S. Food and Drug Administration. None of the materials reported here produced an increase in UDS and therefore the UDS results with these compounds do not suggest potential for genotoxicity.     

Expression of prostaglandin endoperoxide synthase-1 in a baculovirus system.

A cDNA coding for ovine prostaglandin endoperoxide (PGH) synthase-1 was used to construct a recombinant baculovirus which was expressed in Spodoptera frugiperda (Sf9) insect cells. Two proteins reactive with anti-PGH synthase antibody were produced. A larger protein (Mr = 72,000) coelectrophoresed with native enzyme; a smaller, more abundant protein (Mr = 66,000) was unglycosylated enzyme. About 90% of both the immunoreactivity and the cyclooxygenase activity were present in a low speed (10(5) g x min) pellet; variable but low peroxidase activities were observed in this fraction. The specific cyclooxygenase activity of solubilized PGH synthase-1 from Sf9 cells was 56 units/mg versus 112 units/mg for the same cDNA expressed in cos-1 cells. The baculovirus-insect cell system is not ideal for generating large amounts of active PGH synthase-1 apparently because of inefficient N-glycosylation.     

The influence of organic ligands on the growth of phytoplankton in the northwest African upwelling region

Chelation bioassays were conducted off the coast of northwestAfrica during two seasons. The first (winter) was characterizedby strong shelf-break upwelling and the second (spring) wascharacterized by upwelling closer to shore. Phytoplankton insamples taken from surface waters during winter showed a markedstimulation in growth upon addition of the artificial chelatorEDTA. Optimal concentrations of the ligand were 10^–6 M.No stimulation was observed during upwelling conditions encounteredin the spring. Primary productivity in the winter season wassignificantly lower than in the spring, averaging only 35% ofthe spring rates. Ionic copper additions reduced growth in phytoplanktonassayed in the spring and the growth reductions were eliminatedby addition of EDTA. It is hypothesized that the winter growthdepression resulted from either (1) a lack of organic compoundscapable of binding ionic copper as a result of either a lackof organic input from the sediments or surface waters becauseof direct advection to the surface, or by (2) the upwellingof water from a ligand-deficient water mass whose relative importanceas a source for newly upwelled water declined and disappearedas the season progressed.     

Identification of two cosmids derived from within chromosomal band 3p21.1 that contain clusters of rare restriction sites and evolutionarily conserved sequences.

We have isolated large numbers of human recombinants from a cosmid library constructed from an interspecific (hamster/human) somatic cell hybrid whose only human component is an intact chromosome 3. Unique sequence probes were isolated from these recombinants and were used to localize them along the length of chromosome 3 by hybridization to a somatic cell hybrid deletion panel. We identified two cosmids, cA84 (D3S92) and cA199 (D3S93), derived from within chromosomal band 3p21.1. Both cosmids contained multiple rare restriction sites that were tightly clustered within the cosmids. We have therefore identified, in a region consistently deleted in a variety of lung cancers, two cosmids that may contain genes that are candidates for involvement in lung cancer.     

Evaluation of a Treadmill with Vibration Isolation and Stabilization (TVIS) for use on the International Space Station

A treadmill with vibration isolation and stabilization designed for the International Space Station (ISS) was evaluated during Shuttle mission STS-81. Three crew members ran and walked on the device, which floats freely in zero gravity. For the majority of the more than 2 hours of locomotion studied, the treadmill showed peak to peak linear and angular displacements of less than 2.5 cm and 2.5 degrees, respectively. Vibration transmitted to the vehicle was within the microgravity allocation limits that are defined for the ISS. Refinements to the treadmill and harness system are discussed. This approach to treadmill design offers the possibility of generating 1G-like loads on the lower extremities while preserving the microgravity environment of the ISS for structural safety and vibration free experimental conditions.