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Incorporation of 14C-phenylalanine in in vitro systems from sugar pine ( Pinus lambertiana ) seeds was studied. Embryo ribosomes from both dry and stratified seeds supported incorporation (431 and 326 pmoles, respectively, of phenylalanine per mg ribosome) when combined with an embryo pH 5 fraction from stratified seeds. Female gametophyte ribosomes from dry seeds were active (302 pmoles phenylalanine incorporated per mg ribosome) but lost 61 percent of their capacity to support protein synthesis after 35 hours' stratification. The pH 5 fraction from embryos increased in capacity to support incorporation as stratification progressed up to 60 days (398 pmoles phenylalanine per mg ribosome when ribosomes were from 90-day stratified embryos) while the pH 5 fraction from female gametophytes was never active.

The ultrastructural changes occurring in cotyledon protein bodies of germinating squash seeds were investigated using mainly the freeze-etching technique. The appearance and subsequent disappearance of soft globoid-like material in the proteinaceous matrix was documented as the first major ultrastructural change. The globoid crystal was digested either by the formation of internal pitted regions or through external digestion. During later stages of breakdown the protein bodies became a series of largely aqueous vacuoles containing irregularly shaped pieces of protein material. This protein material eventually disappeared and the vacuoles fused to form the central vacuole of the mesophyll cells. This fusion of vacuoles was followed in living cells using Nomarski optics.

The elongation growth of the Avena first internode segments was studied in the presence of one or several of the following growth substances: indoleacetic acid (IAA), 6-fur-furylamino purine (FAP, kinetin), 6-benzylamino purine (BAP), gibberellin A3 (GA3) and A4+7 (GA4+7), and abscisic acid (ABA). The cytokinins at concentrations of 10−7 to 10−6M stimulated growth with 4 to 6 per cent but this effect was not statistically significant. Concentrations higher than 5 × 10−6M inhibited growth. FAP and BAP (from 10−8M to 10−6M) had no significant interaction with any other growth substance used. The two-factor interactions of IAA × ABA, IAA × GA3, and GA3× ABA, as well as the three-factor interaction IAA × ABA × GA3 were significant. However, the IAA × ABA interaction was significant only when high concentration (10−6M) of ABA was used. The growth inhibition produced by 10−7 and 10−6M ABA was overcome by about equimolar concentrations of IAA. The stimulation of growth by GA3 and GA4+7 (10−9 to 10−7M) was prevented by simultaneous application of ABA, and it was reduced significantly by application of IAA (10−7 to 10−8M). GA3 at 10−8M combined with different concentrations of IAA gave slightly higher elongation than IAA alone but the observed values were significantly lower than expected assuming independent additive action.

Similar types of bacteria, selected on the basis of their distinctive colony morphology on mitis-salivarius agar and trypticase soy agar plates, were recoverable from the plaque of weanling littermate rats. The proportional distribution of these bacteria was highly variable within a litter, irrespective of whether a pellet diet or a powdered non-cariogenic diet was fed before weaning, or whether plaque was sampled from the central and distal fissures and the approximal surfaces of lower first and second molars or from only the central fissures of these teeth. Corresponding observations were made in rats fed a cariogenic diet after weaning. In this case, the caries experience of littermates appeared to be less variable than the proportional distribution of bacteria from plaque in the central fissure of their lower first and second molars. The results preclude the extrapolation from one rat to its littermates of quantitative bacteriological data relating to plaque.

The esterification of palmitate by lung homogenates is increased by palmitoyllysolecithin in the presence of CoA and ATP. [32P]lysolecithin can also be converted to [32P]lecithin in the absence of other substrates, suggesting transacylation between two molecules of palmitoyllysolecithin. Some palmitate is esterified in the absence of added lysolecithin, ATP, and CoA. Free palmitate appears to exchange with other esterified fatty acids, especially oleate incorporated into the lecithin of lung tissue slices. The lung contains sufficient 1-palmitoyl-2-oleyllecithin for this exchange to be significant. In homogenates, Ca2+ is required for the exchange and the incorporation of palmitate. The in vivo turnover of the oleate in the lecithin of lung tissues and bronchiolar washings is more rapid than that of the palmitate. This is consistent with a mechanism of dipalmitoyllecithin synthesis involving exchange of esterified oleate for palmitate in lecithin. It is concluded that in addition to de novo synthesis of lecithin in the lung, incorporation of activated palmitate into lysolecithin and exchange of palmitate with oleate esterified in endogenous lecithin also occur. Phospholipase activity is probably involved in the latter two pathways.

Summary Nine different yeasts (2 Saccharomyces-cerevisiae-strains, Saccharomycodes ludwigii, Kloeckera apiculata, Hansenuia anomala. Schizosaccharomyces pombe, Candida crusei, Candida pulcherrima, Pichia membranae-faciens ) were tested in an synthetic substrate for their ability of fermentation and their by-products formed during it. (1) Fermentation and the forming of by-products in a synthetic substrate can be compared with those in grape must. (2) Only one strain of Sacch. cerevisiae ferments sugar approximately quantitative. The secound strain of Sacch. cerev. and Saccharomycodes ludwigii ferment only 83%, Kloeckera, Hansenula and both strains of Candida 20–65%, Pichia and Schizosaccharomyces ferment under these conditions all but nothing. The production of acids increase with fermentation ability. (3) Less good fermenting Saccharomyces and Saccharomycodes surpass the best fermenting Saccharomyces in the production of glycerol. Also other slowly — fermenting yeasts produce relative more glvcerol —. With Pichia and Schizosaccharomyces the production of both pyruvate and acetal lehyde is most, likely the consequence of the minimum of sugar catabolism. (4) The production of propanol is limited in the main to the good fermenting yeasts and Hansenula . The production of isobutanol is rather high with most of the yeasts, best with Saccharomycodes , worst with Kloeckera . With the latter the production of heigher alcohols on the whole is insignificant. The production of amylalcohols depends on the fermentation: in slow fermentation the amount of 2-methylbutanol increases in relation to the amount of 3-methylbutanol. With good fermenting yeasts the total of both amylalcohols is high, but also the poor fermenting yeasts produce remarkable amounts. (5) No production of isoamylacetate takes place, but for two exeptions. Aethylaeetat was produced by all yeasts (mostly 20–60 mg./l.). Much more was produced by both species of Candida and Hansenula (137–220 mg./l.).

Fetal pulmonary maturation has been studied both by gas—liquid chromatography of fatty acids and silica gel chromatography of phospholipids. Variations of two ratios: Lecithin/Sphingomyelin, (L/S), and Palmitic acid/ Stearic acid, (P/S), have been followed during normal pregnancies in 94 samples of amniotic fluid. P/S appears much more accurate and reliable than L/S in our experience.

A “hot-pack” process will pasteurize egg products containing salt. Both Staph. aureus and S. oranienburg are destroyed at inoculum levels of 106 cells/g. The process is as follows: Preheat the product in a vat or other heat exchanger to near 52° C. within ca. one hr. Add 10% salt either before or during preheating. Package the hot product before cooling and place in a “hot-room.” The following conditions are adequate: 10% salted egg yolk, held at 52° C. for 72 hr.; 10% salted whole egg, held at 52° C. for 48 hr. These heat treatments result in essentially sterile products. A fast come-up time is important, otherwise spoilage may occur. The emulsifying properties of these “hot-pack” pasteurized products are not adversely affected. Freezing these products after heating for extended periods improved the viscosity and stability of mayonnaise.

The PCBs tested with caged White Leghorn hens were ‘Aroclors 1221, 1232, 1242, 1248, 1254, 1268, 5442 and BP-6’, fed at the 20 ppm level. In addition, 1242, 1248 and 1254 were also fed at the 2 ppm level. Feeding 20 ppm ‘Aroclors 1232, 1242, 1248 and 1254’ reduced hatchability and caused teratogenic effects in the embryos. The most common abnormalities found in the unhatched embryos were edema and unabsorbed yolk. Since ‘Aroclors 1221 and 1268’ did not adversely affect embryonic development, adverse effects of the PCBs were not directly related to the degree of chlorination of the biphenyls, or to the amount of total residue.

Thiobacillus intermedius grows in glucose-mineral salts medium supplemented with any or all of seven reduced organic sulfur compounds but does not grow in the absence of the supplement(s). This growth represents a physiological capability of T. intermedius and does not result from contaminated or mutant cultures. T. intermedius is not capable of assimilating sulfate; exogenous 35SO4-is not incorporated by T. intermedius growing autotrophically or heterotrophically. The demonstrated need for a reduced sulfur source explains the previously reported inability of T. intermedius to grow in glucose-mineral salts medium.

An isolation procedure is described in which, in the presence of a SH-blocking agent, DTNB, LP-B, and albumin-free HDL2 and HDL3 were isolated. Subfractionation on hydroxylapatite column chromatography of HDL2 and HDL3 respectively, gave three parent fractions of characteristic polypeptide composition. HDL3 fractions I and II contained the thin immunoprecipitin line peptide, LP-D. Incubation in vitro of HDL3 fraction II caused degradation of the fraction, simultaneously with the appearance of newly formed cholesterol ester and a consumption of lecithin. Re-chromatography of the degraded HDL3 fraction II gave three daughter fractions, one of which contained LP-D with lysolecithin as its characteristic phosphatide and some neutral lipids (cholesterol). It is suggested that the degradation was caused by lecithin: cholesterol acyltransferase reaction and that LP-D may be the specific carrier for the substrate lecithin and/or the product lysolecithin of HLD3.

Microsomal mixed-function oxidase (MFO) was characterized in liver of freshwater fishes, bass, Micropterus dolomeiux , and bluegill, Lepomis macrochirus , using the chlorinated cyclodiene insecticide aldrin as a substrate. The MFO activity of bluegill adults, bluegill fry, and bass fry using cyclodienes as substrates was compared with that of mouse. Aldrin epoxidase activity was found to be high in bluegill fry (73% of the activity in mouse) compared to bluegill adults (13% of the activity in mouse). Chlordene was found to be metabolized by both fish and mouse MFO to chlordene 2,3-epoxide and 1-hydroxychlordene. Competitive inhibition between various cyclodiene substrates studied in mouse and fish showed that endrin was a potent inhibitor of aldrin epoxidation in vitro .

SUMMARY Proteose-peptone agar was defective for the culture of H. influenzae from small inocula when sterilising temperatures exceeded 116°C. All 23 strains tested grew poorly or not at all on the medium sterilised at temperatures of 121°C or more for 30 min. The inhibition was more marked when 5% CO2 was present during incubation. The inhibitory effect disappeared after the medium had been stored at 4°C for 7 days before inoculation, or could be abolished by the addition of a reducing agent such as sodium dithionite 100 μg per ml. The growth of H. influenzae may also be adversely affected by agar. Of three commercial agars tested, one batch of a particular brand was found to be inhibitory when used from a freshly opened bottle. Inhibition could not be demonstrated after the agar was washed or in the presence of sodium oleate (4 μg per ml).

Lysolecithin concentrations in the aortic intima plus inner media are greatly increased with atherosclerosis in squirrel monkeys, and with the associated hyperlipemia more than half of plasma lysolecithin is found in the lipoproteins. To explain these findings we studied the metabolism of lysolecithin labeled with [l-14C]-palmitate and [Me-3H]-choline in vivo in squirrel monkeys and in vitro in aortas of squirrel monkeys and rabbits. The binding in vitro of lysolecithin to plasma proteins and lipoproteins, as well as to tissue fractions, was also measured. Plasma lysolecithin rapidly entered all tissues including the brain and was directly acylated or hydrolyzed. The H2O-soluble products of lysolecithin hydrolysis were present in some tissues but not in others such as the aortic wall. Glycerol phosphorylcholine diesterase appeared to be absent from the aorta. Lysolecithin uptake by the intima plus inner media was greatly increased by atherosclerosis, but the fractional turnover was reduced. The rate of to...

Summary Uptake and metabolism of the synthetic auxin α -chloro- β -(3-chloro-o-tolyl)propionitrile (Cl-ClTPN) were studied in intact Mung bean seedlings and in hypocotyl segments. Cl-ClTPN was taken up much faster by hypocotyl segments than by roots of intact plants. In extracts of plants treated with Cl-ClTPN several metabolites were detected: α -chloro- β -(3-chloro-o-tolyl)propionic acid, α -hydroxy- β -(3-chloro-o-tolyl)propionitrile and α -(3-chloro-o-tolyl)acetic acid (ClTAA). Besides, a lot of unidentified metabolites, most of them being apolar, could be revealed. From the identified metabolites and from the growth promoting activity of several homologues of them in the Avena cylinder test, it is suggested that Cl-ClTPN is converted to ClTAA, which is supposed to be the physiological active form of Cl-ClTPN.

Fast freezing and slow thawing Salmonella anatum cells in various milk components inactivated from 20 to 98% of the cells and damaged 40 to 90% of the cells surviving the treatments. Injured cells failed to form colonies on a selective medium (xylose-lysine-peptone agar with 0.2% sodium deoxycholate) but did form colonies on a nonselective plating medium (xylose-lysine-peptone agar). The major milk components—lactose, milk salts, casein, and whey proteins—influenced the extent of injury, repair of injury, and death. The percentages of cells injured and inactivated were decreased by the presence of any milk components except whey proteins. Also, repair of injury was promoted by the presence of each milk component except whey proteins, which in contrast inhibited repair. Phosphate was the most influential milk salts component that protected the cells and promoted repair of injury. These individual milk components may have decreased the extent of freezing-induced death and cellular damage by stabilizing the S. anatum cell envelope.

SummaryThe radiosensitivity of sperm of Drosophila melanogaster was enhanced by a factor of about two by commonly-used food additives. Neither butylated hydroxyanisole (BHA) nor butylated hydroxytoluene (BHT), with and without gamma-irradiation (0, 1·2, 2·4 and 3·6 krads), had any noticeable effect on the sex-ratio. At the concentration used (0·001 per cent BHA; 0·001 per cent BHT), the two phenolic antioxidants seem to induce XB-chromosome loss in the sperm (XO males in F1) and sex-linked recessive lethal mutations in F2, although these effects were not statistically significant. However, both agents proved to be potent radiosensitizers for the sex-linked recessive lethals.

Sublethal heat treatment of two strains of Escherichia coli caused injury of the cells to be expressed, when they were plated on violet red bile agar compared to nutrient agar. Subsequent incubation in tryptic soy broth at either 20 or 37°C supported the resuscitation of the cells from injury, before the end of the lag phase. However, at a typical refrigeration temperature (4.4°C) resuscitation did not occur. In addition to resuscitation for growth on violet red bile agar, resuscitation for growth on the nonselective control medium (nutrient agar) also occurred.

A total of 10,470 donors was tested for hepatitisassociated antigen (HAA) and HAA antibody by immunoelectroosmophoresis and agar gel immunodiffusion technics. Of the donors studied, 73 were found to be positive for HAA and 65 for anti-HAA, 39 of whom were not among the HAA-positive. It appears that a significant additional number of potential carriers can be detected by testing for HAA antibody. Testing for both HAA and anti-HAA can be performed easily, with only a slight increase in time, effort, and cost.

Exposure of juvenile largemouth bass and bluegill to silver (0.3 to 70 ug/liter) resulted in accumulation of this metal. The quantity of metal accumulated increased as exposure concentration increased with a subsequent equilibrium developing between the water and tissue concentrations. Metal accumulations in the bass tissues were highest in the internal organs, followed by the gills and remainder of the body. The greatest increase was exhibited in the gills. Zinc concentrations in the bass body remainder and the bluegill total body appeared to vary in an approximately inverse relationship to the initial accumulation of silver within the tissues. The bass were more sensitive to silver than the bluegill. Abnormal behavior patterns were observed in both species.

The mechanical properties of gelatin films were studied in relation to the effect of water, and compared with those of collagen films. The S-shaped sorption isotherm was separated into an adsorption curve C1 and dissolution curve C2. From the C2 curve, the interaction parameter χ1 of Flory–Huggins' equation was calculated. The χ1 of gelatin were larger than those of collagen at low relative humidities (RH), while they coincided with each other at high RH. It was found that a composite curve was made by shifting stress relaxation curves obtained at different humidities along the log time axis. The shift factor for the formation of the composite curve was analyzed by Fujita–Kishimoto's equation, which was based on the free volume theory. The parameter β, which expressed the extent of the contribution of sorbed water to the increase in the free volume of the system, was 0.05 in the range of C2 from 0 to 0.08 (0–65% RH). This value was much smaller than 0.16 for collagen. The value was 0.16 in the range of C2 higher than 0.08, which was equal to that of the collagen. Dynamic shear modulus G′, loss modulus G″, and tan δ were determined as functions of RH. The gelatin film extended more than 100% at 73% RH under the very small stress of about 107 dyn/cm2. This corresponds to the region where β changes from 0.05 to 0.16, although such a phenomenon was not observed in the collagen film. The wide-angle X-ray pattern of extended gelatin was similar to that of renatured collagen fiber.

The presence of small quantities of 4-methylimidazole (4-MeI) in caramel color has been confirmed by retention time data, and infrared and mass spectroscopy. This paper describes a method for the quantitative extraction of 4-MeI from caramel color, and two chromatographic procedures—thin-layer (TLC) and gas-liquid (GLC) chromatography—for the quantitative determination of 4-MeI in the extracts. The accuracy and precision of the extraction and the chromatographic procedures were tested by analysis of: (a) model caramel color systems; (b) samples of experimental caramel colors of low 4-MeI content; and (c) duplicate samples of caramel color by two participating laboratories. The extraction procedure permits the quantitative recovery of 4-MeI from samples of caramel color; the TLC and GLC analysis procedures provide approximately equal accuracy, with somewhat greater precision afforded by the GLC procedure. The GLC procedure is therefore recommended when precise determinations of 4-MeI concentrations are required; the TLC procedure is recommended for screening studies where a rough estimation of 4-MeI is sufficient.

The genetic basis of yolk cholesterol level was studied in two randombred populations (AC and ARB) of domestic fowl. The association of yolk cholesterol levels with blood cholesterol levels, fertility, hatchability, mortality, egg production and specific gravity were also examined. The yolk cholesterol content in the AC population was 22.8 ± 2.8 mgs. cholesterol per gram of yolk compared to 19.2 ± 1.2 mgs. in the ARB population. There was a significant sire effect on yolk cholesterol level in both populations, but the variability was greater in the AC population. The mean heritability estimate for yolk cholesterol in the AC population was .3, while for the ARB population it was .2. There was no statistically significant phenotypic correlation between yolk cholesterol level and hatchability, fertility, specific gravity or mortality. A significant correlation between yolk cholesterol level and egg production was observed, but this correlation was of low magnitude.

Summary Eleven hundred and twenty-eight strains of anaerobic diphtheroids from human skin could be divided into two groups according to their colonial morphology on casein-yeast-lactate-glucose agar and their susceptibility to lysis by bacteriophages. Members of group I were sensitive and those of group I1 resistant to the action of phage. Biochemical tests confirmed this division among 200 strains, and permitted a subdivision of group I1 into a proteolytic and a non-proteolytic subgroup-IIA and IIB respectively. A simple scheme, based on colonial morphology, phage susceptibility, the production of indole, nitrate reduction, DNAase, gelatinase and caseinase formation, haemolysis, and the acidification of sucrose, sorbitol, and trehalose, could be used for the classification of these organisms. Members of group I were most numerous on the skin of the scalp, forehead, and back, and in follicular material from the alae nasi. Group-IIA strains were found most often in the axilla, and group-IIB strains were occasionally present in small numbers at all sites.

Disc-gel electrophoresis of 26-day-old petri plate cultures of 3+ and 3- strains of A. tubenulatum, grown separately and together (3181 × 3182 and 1593 × 1967) to form gymnothecia on modified cereal agar, was performed for their protein, peroxidase, esterase, and polyphenol oxidase patterns. There were more protein and peroxidase bands in + strains that in the — strains. When crossed, gymnothecial cultures produced 1·5 to 2 times more protein bands than when grown separately, but the peroxidase isozymbes were the same in number in crossed cultures as in — strains. More esterase bands were found in — strains than in + strains and in the crossed cultures. The number of esterase isozymes in + strains and in the gymnothecial cultures was the same, but their patterns appeared to be somewhat different. None of the + and - strains nor the gymnothecial cultures showed polyphenol oxidase activity. The results indicate that the mating types of A. tuberculatum differ from each other in their protein, peroxidase, and...

Day and night catches of biting flies (excluding Culicidae) were made from bullock, buffalo and at light at Katookye, western Uganda, between July 1966 and August 1967. The 39 species caught were classified according to the time of day at which they bit. The seven Groups and the most commonly caught species are as follows: Group 1, Ceratopogonidae (purely nocturnal) and Glossina fuscipleuris Aust., Stomoxys ochrosoma Speiser and Haematobosca squalida (Grünb.) (diurnal and nocturnal); Group 2 (early morning peak),Haematobia minuta (Bez.),H. spinigera(Mall.)and H. thirouxi (Roub.); Group 3 (mid-morning peak), Tabanus taeniola P. de B. and T. thoracinus P. de B. Group 4 (mid-morning and late afternoon peaks), G. pallidipes Aust. males and Haematobosca latifrons (Mall.); Group 5 (early morning and evening peaks), Haematopota brunnescens Ric. females, H. patellicorne (End.) females, Stomoxys taeniata Big., S. nigra Macq., S. inornata Grünb. and S. omega Newst.; Group 6 (midday to mid-afternoon peak), G. pallidipes females, H. brucei Aust. females, T. par Wlk. females and Chrysops distinctipennis Aust. females; and Group 7 (progressive increase in biting from morning till evening), G. fuscipes Newst. and S. calcitrans (L.).

The position of the bolus in persons with mandibular prognathism was examined using a cineradiographic method before and after surgical correction of the prognathism. The pre-operative study included 30 persons, 18 women and 12 men. The test foods were bread and toffee. The results showed that the upper incisal region participated more and the premolar and molar regions less frequently in the chewing act than in other patient groups examined earlier with the same method. This was especially the case in persons with pronounced mandibular prognathism. It was concluded that these patients may have a poor masticatory ability.The post-operative registration was carried out on 23 of the patients. The results showed a more «normal» chewing pattern with a higher participation of the molar region. Due to this change the possibilities for a good masticatory function was considered increased after operation, but whether the chewing efficiency was improved could not be decided from the present study.

A pectin isolated from rapeseed, hulls by extraction with aqueous ammonium oxalate, had a degree of esterification of 83% and contained residues of hexuronic (mainly D-galacturonic) acid (76%), D-galactose (2–3%), L-arabinose (8–9%), D-xylose (2%), L-rhamnose (2–3%), and L-fucose (1%). Partial acid hydrolysis of the derived pectic acid furnished 2-O-(α-D-galactopyranosyluronic acid)-L-rhamnose, 4-O-(α-D-galactopyranosyluronic acid)-D-galacturonic acid and the polymer-homologous tri- and tetrasaccharides, and 4-O-(glucopyranosyluronic acid)-L-fucose. The cleavage products from the methylated pectin were examined by g.l.c. and the partially methylated alditol acetates from the methylated carboxyl-reduced polysaccharide by g.l.c.-mass spectrometry. Parallel methylation studies on lemon-peel pectin have established a close similarity between the two pectins.

Summary Trials were undertaken to study the direct effect of different temperatures and time of exposure under anaerobic conditions on the chlamydospores and mycelium of loose smut of wheat — Ustilago tritici (Pers.) Rostr. — with different moisture contents. Several different laboratory techniques were employed to test the effect of anaerobic conditions on loose smut of wheat. The chlamydospores of loose smut of wheat, used in the trials, were of various origin. Chlamydospores from the ears of different wheat varieties were tested. They were 1–5 months old, and kept at the temperatures ranging from 8 to 20 °C during storage. No chlamydospore germinability and no wheat loose smut mycelium growth were observed during exposure to anaerobic conditions. When the exposure to anaerobic conditions was stopped and the chlamydospores and mycelium were subjected to aerobic conditions (grown in Petri dishes on sweet wort agar), the chlamydospore germination and mycelium growth were found to be inhibited, or the parasite was killed. It was found that there were some correlations between the mentioned factors affecting loose smut. Anaerobic conditions were more effective when the temperatures and the moisture levels in the spores and mycelium were higher and the time of exposure longer. The study has yielded new findings supporting our theory ( Ujevic 1958) according to which the mycelium of loose smut in grains is killed as a result of a direct complex and selective effect of the mentioned factors on the parasite. Our theoretical conclusions differ from the to-date theory asserting that the parasite mycelium is killed by the toxic substances produced in grains during seed disinfection by some physical methods.

Selected Salmonella and Arizona isolates made resistant to chlortetracycline (CTC) by transfer of R factor from donor Escherichia coli or by incubating them in media containing increasing concentrations of CTC were compared in pathogenicity to the drug-sensitive strains from which they were developed. The Salmonella or Arizona strains were administered in varying doses by injection into yolk sacs of day-old chicks; the criteria for evaluating pathogenicity were LD50 at 48 hrs. post inoculation and mortality during the 7-day post inoculation period. Growth rates of drug-resistant and drug-susceptible strains of Salmonella and Arizona in the yolk sac and their rates of invasion of the liver were also determined. The LD50’s of antibiotic-sensitive and R factor-containing strains of the same species did not differ significantly. These strains also demonstrated almost identical degrees of invasiveness, and caused equal percentages of mortality in chicks during the 7-day post inoculation period. The growth patterns in chicks’ yolk sacs of sensitive and R factor-containing strains were similar except for the occurrence of a lag phase in the latter strains. The levels of drug resistance conferred by R factors were high and there seems to be no correlation between level of drug resistance and virulence. Adaptively resistant (AR) mutant strains produced by incubation in increasing concentrations of CTC caused less mortality than did their drug-sensitive and R factor-containing counterparts.

The indirect immunoperoxidase technique with type-specific antisera was compared to kinetic neutralization for the typing of herpes simplex virus strains. There was complete agreement between the results obtained by kinetic neutralization and indirect immunoperoxidase. The indirect immunoperoxidase assay was far simpler to perform and interpret than the kinetic neutralization tests, and it offered a rapid means for the routine antigenic typing of herpes simplex isolates.

The incomplete absorption of dietary cholesterol may represent an adaptive intestinal barrier that prevents hypercholesterolemia. To explore this mechanism, we compared cholesterol absorption in 15 normocholesterolemic and 6 hypercholesterolemic (type II) subjects fed background cholesterol-free formula diets with 40% of calories as fat. Each test meal consisted of a breakfast into which was incorporated scrambled egg yolk containing 300-500 mg of cholesterol and [4-(14)C]cholesterol (3-22 muCi), either naturally incorporated into the yolk cholesterol by previous isotope injection into the laying hen or added in peanut oil to the yolk of the test breakfast. In some instances [1alpha-(3)H]cholesterol was the radioactive marker. The radioactivity of the fecal neutral sterol fraction was determined in daily stool samples for the next 7 days to provide an estimate of unabsorbed dietary cholesterol. The amount of absorbed and reexcreted labeled cholesterol proved negligible. Most unabsorbed dietary cholesterol appeared in the stool on the second or third day after the meal, and 95% or more was recovered in the stool by 6 days. Plasma specific activity curves were usually maximal at 48 h. Normal subjects absorbed 44.5+/-9.3 (SD) of the administered cholesterol (range 25.9-60.3). Hypercholesterolemics absorbed the same percentage of cholesterol as normals: 47.6+/-12.6% (range 29.3-67.3). Absorption was similar whether the radiolabeled cholesterol was added to egg yolk or naturally incorporated in it (42.1+/-9.3 vs. 48.9+/-9.8%). Six normal subjects were fed a cholesterol-free formula for 4 wk, and then different amounts of cholesterol (110-610 mg/day) were added for another 4 wk. At the end of each period, single test meals containing either 110, 310, or 610 mg of cholesterol and [1alpha-(3)H]cholesterol were administered. Cholesterol absorption was 42.3+/-6.0% and 45.4+/-8.3% for the two dietary periods, respectively. The absolute cholesterol absorption was linearly related to the amount of cholesterol in the test meal, and absorption was not affected by background diets high or low in cholesterol content.

A technique is described for observing bacterial colony growth. Bacillus cereus, B. subtilis , and B. cereus var. mycoides were grown on strips of dialysis membrane layered on nutrient agar. Microcolonies of the organisms on strips were fixed in Formalin vapor in situ; the strips then were removed from the agar and secured to scanning microscope specimen stubs without markedly disturbing the cellular arrangement. Scanning electron micrographs clearly depict morphology of individual cells, as well as the spatial orientation of cells within the colony. This technique is reproducible, adaptable, and simple.

Large type Broad Breasted White turkey hens were used in a comparison of liquid smoke and dry smoke curing. Liquid smoke curing resulted in an increase in finished raw carcass weight compared to the fresh carcass weight. Dry smoked carcasses weighed less than the fresh carcass. There was no difference in percentage cooking loss between treatments. A taste panel found no significant differences in smoke flavor concentration in either white or dark meat nor a preference of treatment.

The numbers of colonies of Candida albicans which develop resistance to 5-fluorocytosine on 50% serum agar are significantly lower than those developed on 50% urine and Wickerham's agar media. Seru...

The flagellar morphology of 88 Vibrio parahaemolyticus strains, including a strain descended from Fujino's original strain EB101 (= ATCC17802 = KM1339) was studied. EB101 and 83 other strains (95%) showed mixed polar and peritrichous type of flagellation when grown on modified MOF (MMOF) agar after 16-hr incubation at 20 C. Cultures containing numerous peritrichous cells showed wiggly movements in moist preparations and rapidly spreading growth in semisolid agar plates. Peritrichous flagella were easily removed mechanically from the soma. The mean wavelengths of polar and peritrichous flagella were 2.53 μm (normal type) and 1.72 μm (atypical curly type) respectively. Peritrichous cells on solid media appeared after incubation for 2.5 hr at 37 C and 7 hr at 20 C. Overnight incubation at 37 C and acidity of the medium due to fermentation of carbohydrate markedly ruined peritrichous flagella. Electron micrograph of cells grown on MMOF agar revealed a sheathed polar flagellum and unsheathed peritrichous flagella. A hook structure was demonstrated at the proximal end of the latter. Polar monotrichous cultures in MMOF broth sometimes contained some cells having several or many peritrichous flagella of atypical curly type. Seven strains of Vibrio cholerae were exclusively polar monotrichous on solid and in liquid media. The flagellation of V. parahaemolyticus is concluded as being a mixed polar-peritrichous type. This fact would indicate that V. parahaemolyticus should be excluded from the genus Vibrio, since the genus Vibrio was defined as polar monotrichous.

A procedure was developed whereby aerosol droplets of soybean oil (used to simulate undiluted insecticide) that impinged on Aedes taeniorhynchus Wiedemann were observed and photographed with a scanning electron microscope. Few droplets occurred on mosquitoes exposed outdoors, but mosquitoes exposed in wooden chambers had droplets on all sections of their body surface. Highest concentrations were on the wings and antennae. On mosquito wings, droplets ranging in size from two to 16 microns impinged with more efficiency than smaller or larger droplets. All droplets of soybean oil on mosquitoes exposed outdoors measured one to eight microns.

Summary The naturally occurring cytokinin zeatin was administered to intact plants of Coleus blumei and Impatiens sultani four times at weekly intervals. When treating only the young leaves near the apex in Coleus in September/October we find a decrease of the content of sugars and an increase of starch in the leaves. In Februar/March the reverse is true. In Impatiens in Feb/March the content of starch and sugars increases. The different effects in autumn and late winter perhaps result from the different quantity of light or from the different photoperiod at the time of application. The influence of zeatin on the storage of carbohydrates may be interpreted as a general enhancement of anabolic processes without a fundamental alteration of the metabolic situation. In leaves of Coleus in Oct. zeatin causes an increase of total nitrogen, especially due to a strong rise of the soluble nitrogen. When zeatin (10 ppm) was administered by pencil to all green leaves of the plants the protein-N decreases, probably as a consequence of a high hormone supply. The amino acid composition of the TCA-precipitable proteins of the leaves is changed by zeatin. The effects of zeatin are very similar to those of kinetin. The experiments described here, and some other investigations concerned with the influence of zeatin on the composition of lipid fatty acids and on the respiration of leaves, show that too high concentrations of the hormone have a negative influence on metabolism. These disturbances are naturally more obvious regarding N-compounds than in respect to the storage of carbohydrates.

A membrane filter technique using black membrane filters, MacConkey agar and fluorescence under ultraviolet (UV) light was investigated for the quantitative isolation of Pseudomonas aeruginosa from swimming pools. Three thousand four hundred forty-five samples were collected from public swimming pools and enumerated by this method over a 6-month period. Fluorescent cultures were isolated from 222 specimens. Seventy-seven of these fluorescent cultures were selected for biochemical screening, with 75 (97%) being verified as P. aeruginosa . To further assess the specificity and sensitivity of this UV screening technique, a comparative study was made of some morphological and biochemical characteristics of fluorescent pseudomonads obtained from different sources. The sensitivity of the method was unimpaired by either colony types or biochemical variations of P. aeruginosa . The failure of the other two fluorescent species, P. fluorescens and P. putida , to grow and/or fluoresce on MacConkey agar at 37 C illustrates the specificity of this technique. Further studies are needed to compare the viability of P. aeruginosa on MacConkey agar to that of efficacious nonselective media.

Histochemical and electron microscopic studies of the vitellaria of three polyopisthocotylean fish-gill flukes,Diplozoon paradoxum, Diclidophora merlangi andD. denticulata, and one monopisthocotylean fish-skin fluke,Calicotyle kroyeri have shown that, in each case, vitelline cell development is basically similar. Immature vitelline cells are typically embryonic and undifferentiated. InD. paradoxum they display annulate lamellae, and inC. kroyeri they are invested with flat, sheet-like extensions of the parenchyma. Differentiation into maturing vitelline cells involves the development of extensive GER, Golgi complexes and the production of dense droplets of shell-protein. With the onset of maturity, protein synthesis stops and, as the GER disintegrates, the cell develops food-reserves in the form of yolk bodies, glycogen and lipid. It is then released into the vitelline ductlet. These processes occur in all the follicles at the same time, and all stages of development can be found in any one follicle.

—E. coli K-12 wild-type cells plated immediately after UV irradiation had a much lower survival on minimal medium solidified with agar-agar No. 3 (Oxoid), purified agar (Difco) or ionagar (Colab) than on plates solidified with laboratory-washed Noble agar (Difco). An intermediate survival was obtained on plates solidified with unwashed Noble agar (Difco). When irradiated cells were incubated in liquid minimal medium for various times before subsequent plating on agar-agar No. 3, their survival increased rapidly and became identical to the survival of cells plated on washed Noble agar. The same phenomenon was found with polA 1 cells, but no differences in survival on the different agars were observed with uvrB, exrA, recA or recB cells. These- data suggest that a repair process dependent on the uvrB, recA, recB and exrA (but not the polA) gene products is inhibited when UV irradiated E. coli K-12 cells are plated on minimal medium solidified with agar-agar No. 3, purified agar or ionagar. This implies that the uvr gene-dependent excision-repair process consists of at least two branches, one controlled by the polA gene and a second controlled by the recA, recB and exrA genes and inhibitable by a substance present in certain agars. For maximum sensitivity, experiments designed to study chemical inhibitors of repair should use agar plates that do not themselves inhibit repair.

Using an agar diffusion technique, it was found that leaves from potato plants growing under long days produced more gibberellin-like substances than did leaves from plants growing under short days. Short day plants irradiated with red light during the long dark period and harvested during the ensuing light period, contained levels of gibberellin-like substances approximating those found in long day grown plants. Red irradiation during the long dark period also resulted in an increase in gibberellin production in short day plants. Four zones of gibberellin-like activity (A, B, C, D) were separated by thin layer chromatography in extracts from potato leaves. Red light treatment reduced the levels of peak D and brought about a concomitant increase in the levels of peak A.

Two isoaccepting t RNA Phe were isolated from yellow lupin seeds by DEAE-cellulose, BD-cellulose and reversed phase chromatography. The products obtained were characterized by aminoacylation and fluorescence. The chromatographic behaviour and some properties of the isolated t RNAs are discussed and compared with the known t RNA Phe from other sources.

The effects of feeding broiler-type chickens rations containing 5% or 15% of a low erucic acid rapeseed oil prepared commercially from the Oro variety of rapeseed (ORO), a commercially hydrogenated Oro oil (HORO) and soybean oil (SBO) on body weight, apparent digestibility of total fatty acids, weights of heart, liver and spleen, total lipid and total fatty acid content of heart and liver and fatty acid composition of heart and liver lipids were studied. The experimental diets were fed ad libitum to the chickens from day old to four weeks of age. Body weight and weights of heart and liver were not influenced significantly by the dietary treatments. Spleen weight was smallest in the group fed the 15% ORO—containing diets. The apparent digestibilities of total fatty acids were similar for ORO and SBO (89.4% and 94.2% for 5% and 15% ORO; 90.9% and 94.7% for 5% and 15% SBO), however they were lower for HORO (85.7% and 90.2% for 5% and 15% HORO). Total lipid and total fatty acid contents of liver were not influenced significantly by the different dietary treatments. Feeding 5% ORO in the diet decreased the content of total fatty acids in heart as compared to feeding 5% HORO or 5% SBO in the diet. The fatty acid composition of heart and liver lipids was influenced by the fatty acid content of the diets. Only small amounts of erucic acid were found in the tissues of the birds fed diets containing ORO or HORO. The inclusion of 5% or 15% of low erucic acid rapeseed oils (ORO and HORO) in diets for broiler chickens proved nutritionally as satisfactory as the inclusion of SBO. POULTRY SCIENCE 53: 2108-2115, 1974

A proficiency test for hepatitis-B antigen was carried out under the auspices of the Deutsche Gesellschaft fur Bluttransfusion. 128 participants from 20 European countries reported results obtained with different methods in common use. The test panel of 50 sera contained 40 regarded as HB Ag-positive. The best results were obtained with the complement-fixation (CF) test, which gave correct results in 89% of all samples. Immuno-precipitation electrophoresis (IPE) gave 78%, the latex test 75%, and immunodiffusion 67%. The highest incidence of ‘false’ positives occurred in the latex test (11 out of 22), and there were more false positives with CF than with IPE. For IPE, agarose gave better results than agar on average.

An acid ether-soluble, strongly growth-stimulating substance revealed by the Avena coleoptile straight-growth test in methanol extracts from bean seedlings (Phaseolus vulgaris L.) was identified as indol-3yl-aspartic acid (IAAsp). Points of agreement between synthetic IAAsp and the investigated growth stimulator were indicated by chromatographic behavior, elution volume in gel filtration, mobility in paper electrophoresis, “colour reaction” with DMCA reagent, ability to form indol-3yl-acetic acid (IAA) and aspartic acid after hydrolysis and, finally, biological activity in the Avena test. Furthermore, some experiments demonstrated the occurrence of an inhibitor in extracts from light-grown tissue. This masked the stimulation of IAAsp in the Avena test when the extracts had been chromatographed in isopropanol: NH3:H2 O. A comparison of the levels of IAAsp between green and etiolated tissue did not reveal any distinct difference, demonstrating that the IAA conjugate IAAsp does not participate in the regulation of the photomorphogenesis.