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Previous studies have shown that in sickle trait (AS) donor blood very little sickling is visible. AS donor blood was evaluated by a method of blood filtration, which would be sensitive to intracellular gellation of S hemoglobin which might not be evident morphologically. Blood was collected from normal and sickle trait subjects into CPD solution and stored at 4 C. Blood was removed over a 21-day period and filtered through paper filters at unit gravity and also examined microscopically. Sickling was not evident in saline wet preparations, but was seen in each AS sample in 10 per cent formalin-saline. At 4, 25, and 37 C, AS blood filtered less rapidly than did normal (P < 0.01). AS blood filterability became progressively prolonged as temperature rose; conversely normal blood filterability shortened with increasing temperature. Over 21 days, AS blood remained less filterable than normals. AS samples with high hemoglobin S percentages filtered significantly more slowly than did those with less S hemoglobin. Recognizing that these studies refer only to blood in vitro, no conclusions are drawn with respect to reversibility of the altered filterability or any possible clinical implications.

Homotypically conditioned media (Hom. C.M.) produced by adult Biomphalaria glabrata weighing about 600 mg and fed on pure cellulose under bacteriostatic conditions at a density of one snail per 100 milliliter of standard snail water for three days significantly enhanced the growth of juveniles. Hom. C.M. produced under the same conditions by fasting snails that were previously fed on lettuce, also had a growth promoting effect but was less potent. The growth promoting factors have a molecular weight of 500-104, and appear to act directly on the snails and not indirectly by influencing the food medium. The extent to which absolute growth rate is stimulated by the growth factors correlates well with decrements in the conductivity and calcium concentration of the media. Possible modes of action of the growth factors are discussed. They appear not to influence the relative weights of shell, or body and water content of the snails. It is suggested that the adaptive significance of the growth factors is to facilitate rapid increase in numbers of this gregarious and often fugitive species when environmental conditions are favorable.

Male rats were fed 100 nM dichlorodiphenyltrichloroethane-14C in oil by gastric tube. Recovery of dichlorodiphenyltrichloroethane-14C in thoracic duct lymph was 60% in 12 hr. Lymph dichlorodiphenyltrichloroethane-14C (97%) occurred in lipoproteins of d

The active thiol group of lombricine kinase from Lumbricus terrestris muscle was labelled with N-ethyl-[1-14C]maleimide. The resulting inactivated N-ethyl-[1-14C]succinimido enzyme was then subjected to tryptic hydrolysis. The peptide containing the labelled essential thiol group was isolated and found to contain: Leu-Gly-Tyr-Ile-Thr-[14C]Cys-Pro-Gly-Ser-Asn-Leu-Gly-Thr-Leu-Arg. The amino acid sequence around this thiol group was very similar with that of homologous ATP: guanidine phosphotransferases previously studied, arginine kinase from Homarus vulgaris muscle, creatine kinases from ox brain and ox muscle and from rabbit muscle. In addition among the other enzymes of this group, lombricine kinase is of special interest since it is the only dimeric enzyme of molecular weight ≃ 80000 which possesses only one essential thiol group and one nucleotide binding site per two subunits.

1 A new diagonal electrophoretic technique for determining the order of the lysine-containing tryptic peptides of a protein is described. The protein is converted into its trifluoracetyl derivative, digested enzymatically (or chemically), and the resulting peptides separated by paper electrophoresis. The paper is then treated with ammonia vapour, which re-exposes the ɛ-amino groups of the lysine residues, and submitted to a second electrophoresis at right angles to the first direction. Peptides containing lysine residues, together with the N-terminal peptide of the protein, are found to lie off a diagonal formed by all other peptides, whence they may be readily purified. A study of these peptides enables the order of the lysine-containing tryptic peptides in the protein to be deduced. 2 The technique has been successfully tested with insulin. 3 When the method was applied to porcine pepsin, the four tryptic peptides isolated were easily ordered and the carboxyl-terminal sequence of the protein shown to be Arg-Gln-Tyr-Tyr-Thr-Val-Phe-Asp-Arg-Ala-Asn-Asn-Lys-Val-Gly-Leu-Ala-Pro-Val-Ala. The three basic amino acid residues in the molecule are thus found clustering towards the C-terminus of the polypeptide chain. 4 A common ancestral gene for porcine pepsin and bovine (calf) rennin is suggested by the close homology between the C-terminal sequences of the two proteins.

Starting from 2-thiodeoxythymidine, the mono- and triphosphate of the nucleoside analog were prepared by enzymatic phosphorylation with thymidine kinase and thymidylate kinase, respectively. 2-Thiodeoxythymidine triphosphate was also obtained by chemical pyrophosphorylation of the monophosphate. The analog nucleoside-triphosphate is a substrate for Escherichia coli DNA polymerase. A copolymer consisting of alternating deoxyadenosine- and 2-thiodeoxythymidine nucleotides is synthesized extensively by the enzyme. The polymer was characterized by nearest neighbour analysis, sedimentation and buoyant density in the analytical ultracentrifuge, ultraviolet spectra and stability against thermal and alkaline denaturation.

From the lipopolysaccharides of two Escherichia coli strains (serotypes O 7:K1:(L):H− and O10:K5 (L):H4) two unusual amino sugars were isolated. By sequential oxidation with periodate and hypoiodite, followed by identification of the reaction products, the aminosugars were characterized as 4-amino-4,6-dideoxy-d-hexoses. The chromatographic properties of the amino sugars and their N-acetyl derivatives were compared with those of authentic samples of free and N-acetylated 4-amino-4,6-dideoxy-d-glucose and 4-amino-4,6-dideoxy-d-galactose. On the basis of the results obtained the unknown amino sugars were tentatively identified as 4-amino-4,6-dideoxy-d-glucose (from the lipopoly-saccharide of E. coli O7:K1:(L):H−) and 4-amino-4,6-dideoxy-d-galactose (from the lipopolysaccharide of E. coli O10:K5(L):H4). This is the first time that 4-amino-4,6-dideoxy-d-galactose is described as a constituent of a polysaccharide.

Mast cell granules, obtained from sonically disintegrated rat peritioneal cells and suspended in sucrose, 0.34 M, were found to release histamine in the presence of bee venom. Three venom fractions were obtained by gel filtration; two of these had strong histamine releasing capacity, namely “F I” containing phosphatidase A, and “F III” with direct hemolytic properties. The third fraction, “F II”, which releases histamine from intact mast cells, had little effect on granules. Various possibilities for the release mechanism, namely phosphatidase activity, surface activity, and cation exchange, are discussed.

Pollution preventive measures should be built into the process when a new mill is designed; corrective measures must be taken on existing mills. For air pollution control, these measures consist essentially of enclosing all vessels that contain the black liquor from which the tall oil is recovered. Hoods are placed over storage tanks, sumps, heat exchangers, and other liquor-containing vessels. The hoods must be vented to a ductwork system that brings the off-gases to a central point for disposition. Typical devices to remove the offensive odors and particulate matter in the off-gases are wet scrubbers and incinerators. Evaporation can be used to concentrate liquids containing small amounts of contaminants to much smaller volumes and to concentrations that permit incineration. The lime kiln and recovery boiler of the typical Kraft mill commonly are used to burn the odorous gases, thus destroying the odors completely. Sometimes a separate incinerator is required. Water pollution is best prevented by careful design and operation of the various tall oil removal equipment, such as soap skimmers, level controls, and valving systems. In spite of great care in design and operation, some tall oil will enter the wastewater stream. The effluent treatment plant must be designed to take care of this residual biochemical oxygen demand load and, in some cases, provide for color reduction in the treated effluent.

SUMMARY Radiography using a stabilization paper and a stabilization processor is available and could be valuable in large animal practice. The processor is easily transported and can be used in any dark area where a 115 volt power supply is available. A finished positive radiographic print can be produced in 10 seconds. Good image quality was obtained in pilot studies. It was possible to demonstrate small fracture fragments, vascular channels in the third phalanx and navicular bone, and bone trabeculae. The high contrast and low sensitivity of the stabilization paper necessitated separate exposures for evaluation of soft tissues and bones, and an exposure 7.5 times that used for conventional radiographic film. RESUME La radiographie avec emploi d'un papier fixateur et d'un dispositif fixateur est possible et parait devoir etre utile chez les grands animaux. Le dispositif de developpement est facilement transporte et peut etre utilise dans n'importe quelle zone obscure ou un courant de 115 Volts est accessible. Une radiographie positive definitive est obtenue en 10 secondes. De bonnes images furent obtenues. Il fut possible de mettre en evidence de petits fragments osseux, les canaux vasculaires de la troisieme phalange et les trabecules osseuses. L'image tres contrastee et la faible sensibilite de l'emulsion employee exige des temps d'exposition differents pour l'appreciation des tissu mous et des os, et une exposition durant un temps sept fois et demi superieur a celui necessaire avec les films conventionnels. ZUSAMMENFASSUNG Eine radiographiche Technik, die ein Stabilisationspapier und einem Stabilisationsverarbeiter einsetzt, konnte in der Grosstierpraxis nutzlich sein. Der Verarbeiter kann leicht transportiert und in jeder dunklen Umgebung verwendet werden, wo ein Anschluss an ein 115 Volt-Netz vorhanden ist. Ein fertiges positives Rontgenbild kann innert 10 Sekunden hergestellt werden. Die ersten Untersuchungen ergaben eine gute Bildqualitat. Es war moglich, kleine Frakturfragmente, Gefasskanale in Hufbein und Strahlbein und Knochentrabeculae zu demonstrieren. Der gute Kontrast und die Unempfindlichkeit des Stabilisationspapiers erforderten verschiedene Belichtungen fur Weichgewebe und Knochen und eine 7,5 mal hohere Belichtungszeit als bei konventionellen Rontgenfilmen.