bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of the rate of successful dispersal of a phytoseiid mite, Phytoseiulus persimilis Athias‐Henriot (Acarina: Phytoseiidae) on the persistence in the interactive system between the predator and its prey
Authors: Takafuji Akio
Published: November 2006

Dispersal behaviour was studied on a predacious phytoseiid mite, Phytoseiulus persimilisAthias‐Henriot in response to the density of its prey, Tetranychus kanzawaiKishida. And the effect of the change in the rate of successful dispersal of the predators among patches was tested on the persistence of the predator‐prey system. The results of the study are summarized as follows:

With a severe decline in prey density available per individual predator, the predators exhibited a marked behavioural change and dispersed to other areas.

When two neighboring host plants did not touch with each other and the dispersal of the predators was possible only through a 20cm plywood “bridge” which connected the two plants, the rate of successful dispersal of the predators was only 20 to 25%, whereas it was 95% when the plants touched with each other.

In the system where 32 host plants touched with each other, the predators succeeded in immigrating into all the plants by the 16th day, and they completely eliminated all the prey by the 33rd day.

In another system, the 32 plants were equally divided into eight “patches” which were connected with each other with two of the bridges and the predators could move between them only through the bridges as mentioned above. In such a system the predators and their prey coexisted about three times longer than in the other one.

It is suggested that for a longer continued coexistence of the predators and prey, it would be necessary to introduce more physical barrier against the dispersal of the predators and to provide more chances for the prey to disperse.
Quantitative demography of copperheads, Agkistrodon contortrix (Serpentes: Viperidae)
Authors: Vial James L. , Berger Thomas L. , McWilliams William T.
Published: November 2006

A quantitative analysis of population characteristics is applied to a previously published descriptive natural history of the copperhead (Agkistrodon contortrix).

Mathematical applications have permitted an expanded interpretation of the original field data to a number of dynamic, age‐specific, parameters including life tables, survivorship curves, natality and mortality, rate of population increase, age distribution and reproductive value. Similar data available for other snake populations are meager and only limited comparisons can be made.

The results obtained from our procedures firmly establish the value of reexamining the existing herpetological literature for potential application of methods that will generate quantitative expressions of population dynamics.
Analysis of spatial association between two species based on the interspecies mean crowding
Authors: Iwao Syun'iti
Published: November 2006

Summary and Conclusion

The measurement of spatial association between two species is considered on the basis of interspecies mean crowding. Two indices of overlapping, γ and Cp, are derived as geometric and weighted arithmetic means of the same component ratios related to inter‐and intraspecies mean crowdings. Both indices behave in a similar way, ranging from 1 when the distributions of two species are completely overlapped to 0 when they are completely exclusive with each other. The former is essentially identical with indices proposed byKuno (1968) andPianka (1973), and the latter is a modified form ofMorisita's (1959)Cσ index. Indices to measure the degree of spatial correlation between species, Ω and Rμ, are then derived for both kinds of overlapping indices, which vary from 1 in complete overlapping, through 0 in independent occurrence, to −1 in complete exclusion.

Various kinds of interspecies association are analyzed using these indices and an extended form of the regression graph which provides a convenient way of indicating the spatial interrelation between two species as well as distribution patterns of respective species.

The method presented in this paper may also be applicable to compare temporal distribution patterns between species, similarity between communities, etc. For such a wider application which includes continuous as well as discrete distributions, the interpretation of intra‐and interspecies mean crowdings is not necessarily appropriate, and hence the concept of mean concentration with the symbols and for intraspecies relation and and for interspecies relation is suggested.
The avoidance of superparasitism in four species of parasitic wasp—Mathematical models and experimental results
Authors: Maindonald J. H. , Markwick Ngaire P.
Published: November 2006

Experimental results, and interpretation, are presented which relate to oviposition behaviour in four species of parasitic wasp (Hymenoptera: Chalcidoidea). All lay their eggs in pupae of the common house fly (Musca domestica) and of other flies associated with man. Probability models suggested byD. J. Daley for describing the avoidance of superparasitism are used to analyse the data. Certain of the models considered by previous authors appear as specieal cases. A satisfactory fit was obtained either by assuming a fixed probability of oviposition in an already parasitised pupa, or by using a model motivated by supposing that a female will tolerate without oviposition some fixed number of visits to already parasitised pupae. A third model was considered which makes the probability depend on the number of previous ovipositions in the pupae now visited. In all four species the presence of other females (with parasite: host ratio unchanged) increased the probability of oviposition upon encountering an already parasitised pupa. In the presence of other females Spalangia endius laid an increased number of eggs, whereas the other three species laid fewer eggs.
The importance of non‐linearity: A comment on the views of Taylor
Authors: Itô Yosiaki , Kitching R. L.
Published: November 2006

Taylor's (1984) view that his power law is better measurement of the distribution pattern of animals than 1/k, Iρ and relation because almost all the data on means and variances of given species could be fitted by the power low, was critisized. Changes in values of 1/k, Iρ and suggest the change of distribution pattern of the species, but the data can still be fitted by the power law because of the great linearizing power of log‐log plots, and, using the power law only, we shall overlook the information on the meaningful changes in the distribution pattern.
Reproductive properties of the oriental chinch bug, Cavelerius saccharivorus Okajima (Heteroptera: Lygaeidae), in relation to its wing polymorphism
Authors: Fujisaki Kenji
Published: November 2006

Reproductive properties of the oriental chinch bug, Cavelerius saccharivorus, were investigated for three types of female adults: brachypters produced in both high and low density populations and macropters produced in high density populations. With respect to egg‐laying potential in terms of clutch size, clutch number, and total fecundity, macropters were superior to brachypters produced in the same high density population, although inferior to brachypters produced in the low density population. The mean fecundity of female adults in each type was positively correlated with mean body length.

Macropterous females markedly prolonged their initiation of both copulation and oviposition and had a much longer life span compared with both types of brachypters. However, there was no fundamental difference in reproductive schedules between the two types of brachypters.
Impact of developmental variance on behavior of models for insect populations I. Models for populations with unrestricted growth
Authors: Bellows T. S.
Published: November 2006

The concept of developmental variance is discussed with reference to its use in models for insect populations. When included in a model, developmental variance is typically used to describe the variation of developmental periods among individuals. However, its presence in a model can also have indirect impact on survival and fertility schedules. This impact can lead to significant changes in population growth rates and generation times. These relationships between developmental variance and population growth in models are quantified and discussed.
Resource exploitation of larvae of Gastrophysa atrocyanea Motschulsky and galerucella vittaticollis Baly (Coleoptera: Chrisomelidae) under a limited resource condition
Authors: Suzuki Nobuhiko
Published: November 2006

Resource exploitation by and intraspecific competition in larvae of Gastrophysa atrocyanea and Galerucella vittaticollis were investigated in field and laboratory experiments. Larvae of both species frequently suffered from food shortages in the field. When G. atrocyanea larvae suffered from a food shortage, severe intraspecific competition occurred because of lack of predation and parasitism. This exploitive competition was caused by a local food shortage of the host plant. Individuals survived by fast exploitation when food became abundant (contest type competition). the G. atrocyanea larvae were wasteful of the food resource, and no mechanism by which to economize on the utilization of the resource was acquired because of their exploitation of the abundant resource. In contrast, the G. vittaticollis population probably is regulated by extrinsic factors such as predation and parasitism. Those larvae grew into smaller adults than those of G. atrocyanea under a food shortage, so that their wasted food consumption was lower than that of G. atrocyanea. Although intraspecific competition was similar to that for G. atrocyanea, it was not as severe. The food for G. vittaticollis was apt to be appropriated by other wasteful exploitators such as G. atrocyanea, which was superior in resource exploitation; therefore G. vittaticollis frequently suffered a food shortage. Consequently selection in relation to tolerance to starvation became more acute for G. vittaticollis than for G. atrocyanea, and individuals of G. vittaticollis that could endure starvation better may have been selected.
Effectiveness of second mating for two incompatible types of the citrus red mite, Panonychus citri (McGregor)
Authors: Takafuji Akio
Published: November 2006

Two types of the citrus red mite, Panonychus citri (M.) occur in some pear orchards in the intermediate latitudal areas in Japan during a certain period of the year (Takafuji andMorimoto, 1983): one is a diapausing type (DP) and the other a non‐diapausing type (C). These two types are incompatible: no adult females are produced from the crosses between them (Takafuji andFujimoto, 1985). In the present study, females of each type were doubly crossed, first with a male of the other type, and then with a male of the same type, to examine the effectiveness of the second mating. In the females of the DP type, the second mating with a male of the same type was almost totally ineffective. In contrast, for the females of the C type the effectiveness of the second mating depended on the durations of the first and second matings: the famles produced female offspring only when the duration of the first copulation with a male of the DP type was brief and the second copulation with a male of the C type lasted relatively long. The results suggested that if the two types coexist, the intercrossing between them will favour the C type over the DP type.
A rigorous population model for the brown planthopper, Nilaparvata lugens Stål (Homoptera: Delphacidae)
Authors: Khor K. E. , Chua T. H.
Published: November 2006

A rigorous mathematical model is formulated for describing population growth of the brown planthopper (Nilaparvata lugensStål, Homoptera), a major rice pest in Asia. The model is based on the assumption that the life history of a population can be approximated by breaking it into constant intervals corresponding to the natural stages of the insect's development. Starting with the balance equation ofvon Foerster
urn:x-wiley:14383896:pope0103:equation:pope0103-math-0001

We derived a set of differential equations for the model. The model incorporates density effects on the proportion of macropterous adults and on the nymphal survival rate. The basic biological data used in the model was taken from Japanese sources. The simulation results of the model agree with the main features of Japanese field data. For example, the predicted adult populations for the three generations in a rice crop are 0.16, 1.69 and 3.09 compared to the field data of 0.16, 1.38 and 5.40. Sensitivity experiments have also been carried out to show (i) the effect of the initial immigrant population and (ii) the relative importance of biological vital rates such as fecundity, egg survival rate, nymphal survival rate and adult death rate.
Population ecology of the gall‐forming aphid, Aploneura lentisci (Pass.) in Israel
Authors: Wool David , Manheim Ora
Published: November 2006

Aploneura lentisci (Passerini) (Homoptera, Aphididae) forms kidney‐shaped galls on the leaflets of its primary host, Pistacia lentiscus (Anacardiaceae). Observations on its population dynamics and ecology werecarried out in 1980–1985.

The galls are formed annually on newly‐growing shoots of the same year. Each gall is founded by a single nymph and contains its parthenogenetic offspring. The infestation period (late March‐early April) is short relative to the period of appearance of new shoots. The distribution of galls on the shoots is non‐random (“clumped”). Early shoots emerging near pruning cuts, when the rest of the buds are still dormant, are often very heavily infested.

Clone size within galls increases from 1 in April to several hundred in September (at least 2 parthenogenetic generations). Alates of the last generation leave the galls gradually as they form. By the following March, previous‐year galls contain no live aphids.

Population density of galls varied greatly among years. Possible causes of this variation are discussed.
Strain differences in the hypolipemic action of dietary calcium in mature male rats
Authors: Fleischman A. I. , Yacowitz H. , Bierenbaum M. L. , Hayton T.
Published: November 2006

Two strains of rats, Holtzman and Wistar, were found to differ significantly in serum and fecal lipid response when fed a corn‐soya diet containing 18% added cocoa butter or corn oil and 0.08% or 1.2% calcium. Interactions of strain with fat and with calcium were noted. The Holtzman rat usually had lower serum and tissue lipid levels and higher fecal lipid levels than the Wistar rat. The magnitude of the strain differences is sufficient to explain the incompatibility of results of the different investigators who have been studying lipid metabolism.
Chloroplast pigments of the marine dinoflagellateGyrodinium resplendens
Authors: Loeblich Alfred R. , Smith V. Elliott
Published: November 2006

The photosynthetic marine dinoflagellate,Gyrodinium resplendens, was grown axenically and harvested during logarithmic growth for analysis of its lipid‐soluble pigments. Chlorophylla and 8 carotenoids were isolated from the methanol and acetone extract by column and thin‐layer chromatography. Chlorophyllc was isolated by partitioning the total extract between saline aqueous acetone and hexane.

Absorption spectra taken in hexane, ethanol, methanol and carbon disulfide confirm the presence of β‐carotene, peridinin, dinoxanthin and diadinoxanthin as major carotenoids.

Four new minor xanthophylls are also described, one of which, namedpyrrhoxanthin, resembles an alkali‐labile keto‐epoxide. At least one of the minor xanthophylls occurs as an ester.

Diadinoxanthin fromGyrodinium and antheraxanthin fromEuglena gracilis seem to be identical with respect to absorption curves, polarity, number of 5, 6‐epoxy groups and lack of allylic hydroxyl groups; however, co‐chromatography of stereoisomers after iodine‐isomerization showed slight differences.

Most of the carotenoids are further characterized here by their partition ratios between hexane and 95% methanol. Several of the carotenoids were tested for the presence of 5, 6‐epoxy and allylic hydroxyl groups. Four of the pigments, comprising 91% of the total carotenoids are revealed as 5,6‐monoepoxides by their instability toward dilute acid. One carotenoid resembles a diepoxide
Phospholipid distribution in blood and tissues of some submammalian species
Authors: Belsare D. K. , Roy Chowdhuri D.
Published: November 2006

The pattern of phospholipid distribution in blood and tissues such as liver, heart, and kidney of four representative species of fish, toad, turtle, and pigeon has been studied. The percentage of phosphatidylcholine in plasma was similar, but in erythrocytes the difference was striking. Ethanolamine and serine plasmalogens were absent in the plasma of all the species. In erythrocytes the highest concentration of phosphatidylethanolamine was noted in the toad. The greatest difference in sphingomyelin and plasmalogen concentrations was found between toad and turtle erythrocytes.

In the liver, phosphatidylcholine accounted for more than 55% of the total lipid phosphorus. The percentage of all individual phospholipids except sphingomyelin in kidney was comparable in all the species.
Caltha palustris L. Seed Oil. A source of four fatty acids withcis‐5‐unsaturation
Authors: Smith C. R. , Kleiman R. , Wolff I. A.
Published: November 2006

The seed oil ofCaltha palustris L. yields two unusual polyunsaturated components, all‐cis‐5,11,14‐eicosatrienoic acid (23%) and all‐cis‐5,11,14,17‐eicosatetraenoic acid (1%). The C18 monoene fraction (26%) is a mixture ofcis‐5‐ andcis‐9‐octadecenoic acids (2∶1). The C20 monoene fraction (12%) is a mixture ofcis‐11‐ andcis‐5‐isomers (3∶1).
Search for new seed oils. XV. Oils of boraginaceae
Authors: Miller Roger Wayne , Earle F. R. , Wolff I. A. , Barclay A. S.
Published: November 2006

In a search for a preferred source of γ‐linolenic (all‐cis‐6,9,12‐octadecatrienoic) acid, seed oils of 33 species of Boraginaceae were examined. The desired triene was found primarily in the subfamily Boraginoideae in amounts ranging from 0.2 to 18%. Oils of this subfamily also contain 0.2 to 15% of the tetraene, all‐cis‐6,9,12,15‐octadecatetraenoic acid. Total unsaturation and the relative proportions of the common acids varied widely in oils of the family. Monoene predominated in the subfamily Cordioideae, diene in Heliotropioideae, and a diverse composition among the Boraginoideae; seven had iodine values of 200 or above.Cordia verbenacea seed oil was unique among those examined in having 43% of C20 acids and 23% of components more volatile in gas chromatography than the usual triglycerides.
The occurrence and biosynthesis of gamma‐linolenic acid in a blue‐green alga,Spirulina platensis
Authors: Nichols B. W. , Wood B. J. B.
Published: November 2006

The acyl‐lipid and fatty acid composition of six blue‐green algae, namely,Spirulina platensis, Myxosarcina chroococcoides, Chlorogloea fritschii, Anabaena cylindrica, Anabaena flos‐aquae, and Mastigocladus laminosus is reported.

All contain major proportions of mono‐and digalactosyl diglyceride, sulfoquinovosyl diglyceride, and phosphatidyl glycerol, but none possess lecithin, phophatidyl ethanolamine, or phosphatidyl inositol. Trans‐3‐hexadecenoic acid was absent from all extracts.

The analyses provide further evidence that there is no general chemical or physical requirement for any specific fatty acid in photosynthesis.

S. platensis is unique among photoautotrophic organisms so far studied, containing major quantities of γ‐linolenic acid (6,9,12‐octadecatrienoic acid). This acid is synthesized by the alga by direct desaturation of linoleic acid and is primarily located in the mono‐ and digalactosyl diglyceride fractions.

The possible phylogenetic relationship betweenS. platensis and other plant forms is discussed.
The fatty acid and aldehyde composition of the major phospholipids of mouse brain
Authors: Sun Grace Y. , Horrocks Lloyd A.
Published: November 2006

Phospholipid classes were separated from mouse brain lipid extracts by preparative thin‐layer chromatography (TLC). Methyl esters were prepared from the intact phospholipids by direct transesterification at room temperature in the presence of silica gel by using 0.5m NaOH‐methanol in order to prevent interference by aldehydes or derivatives. Dimethyl acetal derivatives of phosphoglyceride alkenyl ethers (alkenyl moiety with a double bond in 1,2‐position relative to oxygen linkage) were prepared, using 5% concentrated HCl in methanol, followed by preparative TLC for isolation.

The major phospholipids present were ethanolamine phosphoglycerides (EPG) 39.8%, choline phosphoglycerides (CPG) 39.7%, serine phosphoglycerides (SPG) 15.0%, and sphingomyelin (Sph) 5.4%. One‐fifth of the total phospholipids (PL) were in the form of plasmalogens, mainly EPG. Choline and serine plasmalogens were present in trace quantities. The major aldehyde components of the plasmalogens were 16∶0, 18∶0, and 18∶1.

The EPG were rich in long‐chain poly‐unsaturated fatty acids, including 28.8% of 22∶6 and 17.0% of 20∶4, but contained only 7.2% of 16∶0. In contrast, the CPG contained 39.6% of 16∶0, and 31.0% of 18∶1 with a small content of polyunsaturated fatty acids. The SPG exhibited a still different pattern containing 38.2% of 18∶0, 23.2% of 18∶1, 24.3% of 22∶6, 2.9% of 16∶0, and 3.8% of 20∶4.
Rapid determination of double‐bond positions in monoenoic fatty acids by periodate‐permanganate oxidation
Authors: Downing Donald T. , Greene Richard S.
Published: November 2006

Tetramethylammonium hydroxide has been used in the extraction and pyrolysis methylation of the carboxylic acids produced by periodate‐permanganate oxidation of monounsaturated fatty acid methyl esters. This modification of the von Rudloff procedure allows rapid determination of double‐bond positions and analysis of mixtures of positional isomers of monoenoic fatty acids.
Dihydrosterculic acid, a major fatty acid component ofEuphoria longana seed oil
Authors: Kleiman R. , Earle F. R. , Wolff I. A.
Published: November 2006

The seed oil ofEuphoria longana, Sapindaceae, contains 17.4% of 9,10‐methyleneoctadecanoic (dihydrosterculic) acid. This identification is based on information from thin layer chromatography, infrared analysis, gas liquid chromatography, nuclear magnetic resonance and mass spectroscopy. Since GLC of the oil showed components that emerged between the usual triglycerides, the cyclopropanoid acid is apparently a triglyceride constituent. The presence of smaller amounts, less than 1%, of cyclopropanoid fatty acids of different chain lengths is indicated by GLC and TLC analyses of the methyl esters. The other major fatty acids in this oil are: 16∶0 (19%), 18∶0 (7%), 18∶1 (36%), 18∶2 (6%), 18∶3 (5%) and 20∶0 (4%).Euphoria oil contains considerably larger amounts of cyclopropanoid fatty acids than previously reported in other seed oils.
The role of lipids in membrane transport inMycoplasma laidlawii
Authors: Smith Paul F.
Published: November 2006

Pulse labeling of metabolizing cells ofMycoplasma laidlawii, strain B with14C‐glucose results in rapid turnover of the glucose moiety in carotenyl glucoside and phosphatidyl glucose. Pulse labeling also occurs in the fatty acid radicals of carotenyl esters. No labeling of phosphatidyl glycerol, carotenol or monoglucosyl diglyceride occurs. No turnover of14C occurs in diglucosyl diglyceride. Rapid turnover of32P in phosphatidyl glucose, but not in phosphatidyl glycerol, also occurs. The rate of14CO2 evolution is equivalent to the rate of disappearance of14C in total lipids of cells prelabeled with14C‐glucose. β‐Glucosidase inhibition results in inhibition of glucose utilization. The reverse effect is not seen. A theory involving lipids as carriers in the transport of glucose into the cell and acetate, the end product of glucose metabolism, out of the cell is presented. This theory is compatible with known information concerning membrane structure, membrane transport and metabolism in Mycoplasmas.
Flotation rates, molecular weights and hydrated densities of the low‐density lipoproteins
Authors: Lindgren F. T. , Jensen L. C. , Wills R. D. , Freeman N. K.
Published: November 2006

A method involving three computer programs is described for characterizing the major component of the Sf 0–12 low‐density lipoprotein class by its Sf rate, hydrated density and molecular weight. All necessary information is obtained from a standard low and high‐density lipoprotein ultracentrifugal analysis. Moving‐boundary flotation rates are measured in 1.061 g/ml sodium chloride and 1.200 g/ml sodium bromide solutions and are corrected to flotation at zero concentration. Hydrated densities are calculated from η Fo versus ρ plots and minimum hydrated molecular weights calculated using Stokes' frictional factor, assuming spherical molecules. Preliminary application of this procedure indicates higher Sfo rates, higher molecular weights, and lower hydrated densities in females than in males. Molecular weights and standard deviations of the principal Sf 0–12 component for non‐fasting normal adult females and males were 2.36±0.16 and 2.12±0.20 millions, respectively.
Microbial hydration ofCis‐9‐alkenoic acids
Authors: Davis E. N. , Wallen L. L. , Goodwin J. C. , Rohwedder W. K. , Rhodes R. A.
Published: November 2006

The activity of acis‐9‐fatty acid hydratase produced by aPseudomonas sp. (NRRL B‐3266) isolated from soil was compared with that of another isolate previously reported (NRRL B‐2994). The presence of appropriate fatty acids for at least 4 hr during aerobic growth in yeast extract medium increased subsequent enzyme activity. Such cells anaerobically hydrated severalcis‐9‐alkenoic acids to 10‐hydroxy fatty acids and aerobically formed 10‐keto acids, which were partially degraded to shorter chain keto acids. Melting point, gas chromatography, infrared, mass spectrometry and optical rotatory dispersion data are given. Six fatty acids havingcis‐9‐unsaturation produced hydrated products, but several enoic acids havingtrans‐9‐unsaturation or double bonds in other than the 9 position were inactive as substrates. The (−)‐10‐hydroxypalmitic acid produced from palmitoleic acid is considered to have the D configuration. Yields of 71% crude crystalline product from 15 g of oleic acid and 53% from 11 g of palmitoleic acid were obtained in 5‐liter anaerobic fermentations with NRRL B‐3266. Methyl esters, triolein and oleyl alcohol were not hydrated.
Neutral lipid and fatty acid composition of earthworms (Lumbricus terrestris)
Authors: Cerbulis J. , Wight Taylor M.
Published: November 2006

Earthworms (Lumbricus terrestris) were extracted with chloroform‐methanol (2∶1) and examined primarily for neutral lipids and fatty acids. TLC showed spots for sterols, hydrocarbons, free fatty acids, phospholipids and pigments but none for glycerides (tri‐, di‐ or mono). Saponification of the crude lipid extract yielded 32% fatty acids, 25% unsaponifiables and 43% unidentified. The lipid contained 3% hydrocarbon and 16% sterols. GLC of the hydrocarbons showed at least 13 components. GLC of the sterol fraction showed peaks corresponding to cholesterol (the major component), γ‐sitosterol, β‐sitosterol, stigmasterol, campesterol, and ergosterol. GLC showed that at least 38 fatty acids were present, with 18∶1, 18∶2, 18∶0, 20∶1 and 17∶0 predominanting.
Variation in plasma lipids with age and sex in a hypertriglyceridemic rat
Authors: Lenz Paul H. , Fleischman Alan I.
Published: November 2006

A substrain of the Long Evans rat having the characteristics of a common human lipid disorder, hypertriglyceridemia, is described. These rats were found to be hypercholesterolemic, hyperphospholipidemic and normotriglyceridemic during the first month of life when feeding predominantly on the higher lipid, lower carbohydrate content of their mothers' milk. After weaning (22 days of age), when a typical higher carbohydrate and lower fat containing commercial laboratory feed was substituted for mother's milk, plasma cholesterol and phospholipid levels declined and triglyceride levels significantly increased. Electrophoretic analysis of lipoproteins revealed the presence of a pre‐β fraction and the absence of chylomicra, indicating that this rat is a type IV according to the Fredrickson classification system. Glucose tolerance curves remained elevated for a longer period of time and returned to normal more slowly in 1 year old compared to 2 month old males, indicating progressive alterations in glucose metabolism common in a Fredrickson type IV. After weaning, plasma phospholipid, cholesterol and triglyceride levels were significantly higher and body weight significantly lower in the female than in the male. Studies on hematocrit and hemoglobin variations with respect to age in both sexes indicated that the observed plasma lipid changes could not be attributed to hemoconcentration.
Regulation of hepatic carbohydrate metabolism by FFA and acetyl‐CoA: Sequential feedback inhibition
Authors: Weber G. , Lea M. A. , Stamm Nancy B.
Published: November 2006

In recent years experiments in slices, perfused liver and in the whole animal demonstrated that liver carbohydrate metabolism can be controlled by free fatty acids (FFA). Our investigations suggest that FFA and acetyl‐CoA might provide regulation of the rate and direction of opposing pathways of hepatic glycolysis and gluconeogenesis by controlling the activity of key enzyme systems. Long and short chain FFA were observed to selectively inhibit the key enzymes of glucose catabolism, glucokinase, hexokinase, phosphofructokinase and pyruvate kinase. The long chain FFA were inhibitors two magnitudes stronger than octanoate. The FFA were also able to inhibit lactate production in a fortified supernatant fluid system. Acetyl‐CoA inhibited hepatic glucokinase and pyruvate kinase but did not affect liver hexokinase, phosphofructokinase, lactate dehydrogenase, glucose‐6‐phosphatase or fructose‐1, 6‐diphosphatase. The inhibition of glucokinase and pyruvate kinase was dependent on the dose and preincubation time with acetyl‐CoA. The acetyl‐CoA is the end product of the degradation of FFA which in turn is an end product of glucose catabolism; therefore, the inhibition of the three key glycolytic enzymes by FFA and the subsequent reinforcement of the inhibition of glucokinase and pyruvate kinase may be called sequential feedback inhibition. The regulatory role of phosphoenol‐pyruvate, NADH, ATP, alanine and oxaloacetate in the control of hepatic carbohydrate metabolism is discussed.
Methyl octadecadienoates as protectors against inactivation of alkaline phosphatase by γ‐radiation
Authors: Akiya Toshimi , Madson T. H. , Chipault J. R.
Published: November 2006

Methylcis, cis‐, cis, trans‐ andtrans,trans‐9,12‐octadecadienoates protect alkaline phosphatase from inactivation by γ‐rays. The three isomers are equally efficient.
Control of metabolism in brown adipose tissue
Authors: Williamson John R. , Prusiner Stanley , Olson Merle S. , Fukami Miriam
Published: November 2006

Cells and mitochondria were isolated from brown adipose tissue of the adult hamster. Isolated mitochondria did not show respiratory control. Reversed electron transport was demonstrated and the oxidation rates of various substrates were compared. α‐Glycerophosphate gave the highest oxidative rate with isolated mitochondria. The low basal respiration of isolated brown fat cells could be stimulated by catecholamines, oleate, succinate,a‐glycerol phosphate and uncoupling agents. Only norepinephrine or oleate induced respiration was sensitive to inhibition by oligomycin, but this inhibition could not be released by uncoupling agents. Neither atractyloside nor (+) decanoylcarnitine were found to affect respiration, suggesting that mitochondrial nucleotide exchange is slow and that fatty acid oxidation might be carnitine independent. In resting brown fat cells, ATP amounts to 75% of the total adenine nucleotides. NE or oleate caused a small decrease of ATP and a corresponding increase of ADP. Oligomycin caused a partial depletion of ATP content, but subsequent NE addition increased ATP back to control values. This effect was abolished by arsenite. Similarly, uncoupling agents diminished the ATP level which was increased only slightly by NE. Arsenite alone decreased ATP levels to a small extent but a rapid depletion occurred upon subsequent NE addition while respiration was inhibited. Thus, substrate level phosphorylation may be the major energy producing reaction for the generation of ATP and GTP for the activation of fatty acids. Norepinephrine addition to brown fat cells caused an oxidation of pyridine nucleotides, a reduction of flavoproteins and an oxidation of cytochrome b. In constras, succinate produced a reduction of all the components of the respiratory chain. The bioenergetic basis of thermogenesis in brown fat is its high respiratory rate. The rapid respiration induced by norepinephrine or fatty acids appears to be characterized by a low yeild of ATP from oxidative phosphorylation and may be controlled by fatty acid mediated release of energy coupling, possibly by an indirect mechanism.
The comparative oxidation of palmitic, oleic and succinic acids by rat and bat brown adipose tissue homogenates as a function of temperature
Authors: Dryer Robert L. , Paulsrud John R. , Brown Donald J. , Mavis Karol
Published: November 2006

The oxidation of 1‐14C‐palmitic, 1‐14C‐oleic and 2‐14C‐succinic acids to14CO2 by homogenates of brown adipose tissue (BAT) from rat and bat was studied as a function of temperature. In all cases bat BAT gave a greater conversion of added fatty acids to14CO2 than did rat BAT. The conversion of labeled succinate to14CO2 is greater in the bat than in the rat only at low temperatures. In all paired observations below 30 C the energy of activation (EA) of the bat preparations are lower than the rat. This indicates a greater thermal efficiency for the oxidation of the indicated substrates. The bat BAT homogenates show a greater efficiency than rat homogenates in the amount of succinate oxidation associated with the oxidation of long chain fatty acids to CO2. The significance of these findings to thermogenesis by BAT in hibernation and cold adaptation is discussed.
Cholesterol esters of milk and mammary tissue
Authors: Keenan T. W. , Patton Stuart
Published: November 2006

The fatty acid composition and metabolic activity of cholesterol esters in milk and mammary tissue (cow, sow and goat) were investigated. Cholesterol esters of freshly secreted milks incubated at 40 C for 2 hr showed no change in fatty acid composition and no incorporation of 1‐14C‐palmitate. The fatty acid composition of cholesterol esters in the milk of all three species exhibited elevated levels of a unique group of fatty acids when compared to other milk ester lipid classes. This group was comprised of monounsaturated acids and acids with odd numbers of carbons. Tissue cholesterol esters contained lower levels of these acids. Evidence from experiments in which an odd carbon acid (C15) was infused into the lactating mammary gland indicated that the group of unique acids is preferentially retained in the cholesterol ester fraction which is secreted with milk. These infusion experiments also provided evidence that cholesterol esters accumulate in developing milk fat globules in a manner paralleling triglyceride accumulation, and that acyl moieties of cholesterol esters may be desaturated in the form of the intact ester. Our results are compatible with the hypothesis that acyl moieties of cholesterol esters in lactating mammary tissue are turning over rapidly.
Free fatty acids in cultured cells
Authors: Howard Barbara V. , Kritchevsky David
Published: November 2006

A method for isolation and quantitation of cellular free fatty acid has been developed. When this method was used to quantitate the free fatty acid content of various cells and tissues, their levels of free fatty acids were found to vary over a wide range. In comparing tissue culture cells having different levels of free fatty acid, it was demonstrated that the conditions of culture and the type of serum in the medium are not responsible for the difference in levels. Isotopic studies have shown that the cellular free fatty acid is not biosynthesized, but is derived from the free fatty acid of the medium. Preliminary studies on the fate of the intracellular free fatty acid and a discussion of possible factors controlling the level of this compound in cells are presented.
Ceramide phosphorylglycerol phosphate a new sphingolipid found in bacteria
Authors: White David C. , Tucker Anne N.
Published: November 2006

Ceramide phosphorylglycerol phosphate (CPGP) has been identified in the lipid extract of the anaerobic bacteriumBacteroides melaninogenicus. To our knowledge this is the first report of this lipid in biological material. The ceramide derivative contains two phosphates, an amide linked fatty acid and a dihydrosphingosine long chain base. Glycerol diphosphate (PGP) identified by paper and column chromatography can be isolated after mild acid hydrolysis of the ceramide derivative. Inorganic phosphate is liberated quantitatively on treatment of the PGP from the ceramide derivative with alkaline phosphatase. The proportions of the fatty acids found linked to the amide of the dihydrosphingosine (LCB) differ from those esterified to cardiolipin in this organism. The long chain base appears to consist of part of an homologous series of branched and normal LCB containing from 17 to 21 carbon atoms. Previous work has indicated that ceramide phosphorylethanolamine and ceramide phosphorylglycerol (CPG) are present in the lipid extracts ofB. melaninogenicus. By analogy with phosphatidylglycerol synthesis, CPGP is postulated to be an intermediate in the synthesis of CPG.
The effect of dietary sterculic acid on the hepatic lipids of rainbow trout
Authors: Roehm J. N. , Lee D. J. , Wales J. H. , Polityka S. D. , Sinnhuber R. O.
Published: November 2006

Groups of young rainbow trout (5 g) were fed a basal diet containing 9% salmon oil and 1% tristearin with 0, 100 or 200 ppm methyl sterculate. Liver lipids were separated into polar and nonpolar fractions and the fatty acids quantitatively analyzed. Significant elevations of the stearic‐oleic and the palmiticpalmitoleic ratios were found in liver fatty acid composition 10 days after the feeding trial began. Liver triglycerides of fish fed methyl sterculate for 87 days contained only 2–3% docosahexenoic acid as compared to 10.69% in control trout, suggesting an effect on the biosynthesis of long chain polyunsaturates. Dietary cyclopropenoid fatty acids (CPFA) suppressed growth rate during the first part of the 200 day feeding trial. After 90 days no differences in the rate of weight gain were observed between the control and CPFA groups. A seven day feeding trial with 0, 5, 20, 50 and 100 ppm CPFA resulted in a maximum change in the stearic‐oleic ratio at 50 and 100 ppm levels. All levels of CPFA increased this ratio and caused marked alterations in the cellular morphology of the liver.
The lipids of thermophilic fungi: Lipid composition comparisons between thermophilic and mesophilic fungi
Authors: Mumma R. O. , Fergus C. L. , Sekura R. D.
Published: November 2006

The lipid composition of nine thermophilic and nine mesophilic species of seven genera of fungi were compared. The total lipids varied between 8.0% and 54.1% with most fungi possessing between 8.0% and 18.3% lipids. The predominant fatty acids were found to be palmitic, oleic and linolenic. Lesser amounts of arachidic, linolenic, palmitoleic, pentadecanoic, myristic and lauric acids were found. The mesophiles varied between 0% and 18.5% linolenic acid, while the thermophiles did not contain any appreciable linolenic acid (<0.5%). The mesophile,Mucor globosus, and the thermophile,Mucor pusillus, contain γ linolenic acid. The fatty acids of the thermophilic fungi were more saturated than the corresponding mesophilic species.
The incorporation of glycerol into the glyceride‐glycerol of fat cells isolated from chronically cold‐exposed rats
Authors: Hubbard R. W. , Voorheis H. P. , Therriault D. G.
Published: November 2006

The rate of 2‐14C‐glycerol incorporation into the glyceride‐glycerol moiety was measured in isolated fat cells from control rats maintained at 25 C and from animals chronically exposed to cold (5 C) for six to eight weeks. The rate of glycerol conversion (μM/μg DNA/30 min) was less in the cold‐exposed rats, than in comparable controls (1.96±0.14 vs. 2.68±0.17). Very little glycerol was oxidized to CO2 or converted to fatty acids. In both groups of animals, the glyceride‐glycerol formation was apparently stimulated by noradrenaline in the presence of glucose, but this incorporation does not significantly bias the estimation of lipolysis based upon glycerol release.
Lipid composition of beef and human pituitary glands
Authors: Singh H. , Carroll K. K.
Published: November 2006

The lipid composition of beef and human pituitary was determined by chromatographic and spectrophotometric methods. Beef pituitary lipid contained about 25% nonpolar lipids and 75% phospholipids whereas nonpolar lipids made up approximately 60% of the total in human pituitaries. The main nonpolar (i.e., low polarity) lipids in human pituitary were triglycerides, cholesterol, free fatty acids and an unidentified component in the triglyceride fraction. Cholesterol was the major nonpolar lipid component in freshly collected beef anterior and posterior pituitary, but the amount of free fatty acids appeared to increase during storage. Preliminary investigation of the unknown nonpolar lipid in human pituitaries suggested that it was an unsaturated hydroxy compound with no carbonyl functions. Thin layer chromatography indicated that it was also present in smaller amounts in freshly collected beef pituitaries. The main phospholipids of beef anterior, posterior and human pituitary were phosphatidyl ethanolamine, phosphatidyl choline, phosphatidyl inositol, phosphatidyl serine and sphingomyelin. The fatty acid composition of total nonpolar lipids, free fatty acids, total phospholipids, phosphatidyl ethanolamine and phosphatidyl choline of beef anterior and posterior pituitary was determined by gas liquid chromatography. Mixtures of saturated and unsaturated fatty acids ranging from C12 to C22 were present; the main fatty acids were palmitic, stearic, oleic, linoleic and arachidonic.
Fatty acids: XXII partial synthesis of racemic helenynolic acid from crepenynic acid by a possible biosynthetic route and the discovery ofcis‐9,10‐epoxyoctadec‐12‐ynoic acid inHelichrysum bracteatum seed oil
Authors: Conacher H. B. S. , Gunstone f. D.
Published: November 2006

Racemic helenynolic acid has been prepared from crepenynic acid by epoxidation followed by base‐catalyzed rearrangement. This may be the pathway by which helenynolic acid is produced inHelichrysum bracteatum seed oil from the crepenynic acid also present. A reinvestigation of the epoxy acids in this oil has shown thatcis‐9,10‐epoxyoctadec‐12‐ynoic acid accompanies the coronaric acid previously identified.
Cholesterol absorption with different fats following thoracic duct cannulation of the rat
Authors: Klauda Harry C. , Quackenbush Forrest W.
Published: November 2006

Radioactive cholesterol in three unsaturated fats was absorbed into the lymph to the same extent as cholesterol in three saturated fats or in fats which had been stripped of sterols. Absorption on the first day following cannulation was less than half that on subsequent days.
Tropaeolum speciosum seed fat: A rich source ofcis‐15‐tetracosenoic andcis‐17‐hexacosenoic acids
Authors: Litchfield Carter
Published: November 2006

Tropaeolum speciosum seed fat contains 41.6 wt %cis‐15‐tetracosenoic acid and 7.6 wt %cis‐17‐hexacosenoic acid. Unlike nasturtium seed fat (Tropaeolum majus), the 22∶1, 24∶1 and 26∶1 inT. speciosum triglycerides are almost entirely esterified at the 1,3 positions.
Monounsaturated fatty acids of mouse skin surface lipids
Authors: Wilkinson David I.
Published: November 2006

The occurrence of the various positional isomers of monounsaturated fatty acids of mouse skin surface lipids was studied by conventional oxidative cleavage‐gas liquid chromatography techniques. The pattern observed could be accommodated by the biosynthetic scheme proposed elsewhere for rat skin fatty acids, except that 18∶Δ9 replaced 16∶Δ9 as the main precursor.
Incorporation of U‐14C‐leucine into the serum lipoproteins and proteins of partially hepatectomized rats
Authors: Narayan K. Ananth
Published: November 2006

The incorporation of U‐14C‐leucine into five classes of serum lipoproteins and into lipoprotein‐free serum proteins was investigated in partially hepatectomized, sham operated and normal rats. The serum concentration of very low density lipoprotein and the predominant subfraction of high density lipoprotein (HDL2) was considerably reduced in partially hepatectomized rats as compared with both normal and sham operated rats. The incorporation of U‐14C‐leucine into HDL2 of partially hepatectomized rats was only one third and one fourth of that observed with normal and sham operated rats, respectively. On the other hand, the incorporation of the label into low density lipoproteins and into serum proteins was slightly greater in partially hepatectomized rats as compared with normal rats. In sham operated animals, the incorporation into most fractions was considerably greater than those observed with lobectomized and normal rats.
Mass spectrometry of triglycerides: I. Structural effects
Authors: Lauer W. M. , Aasen A. J. , Graff G. , Holman R. T.
Published: November 2006

Mass spectra of several triglycerides of specific structure or with specific deuterium labeling have been measured with a low resolution mass spectrometer. With saturated triglycerides the abundances of ions characteristic of the component acids, [M‐RCO2]+, increase with increasing chain length, and [M‐RCO2CH2]+ decrease with increasing chain length. Unsaturation in the acyl moiety causes the abundant formation of [RCO‐1]+. Structures have been suggested for a number of the main peaks obtained from saturated triglycerides, and high resolution spectra of one triglyceride agree with the postulated structures. The peaks, [RCO+74]+, [RCO+115]+ and [RCO+128+14n]+, represent structures which contain the glyceryl portion of the triglyceride, since in case of the replacement of its hydrogens with deuteriums, these peaks are shifted accordingly. Evidence which indicates the possibility of determining the location of unsaturation by the interruption of homology of the [RCO+128+14n]+ series, brought about by the addition of deuterium to the unsaturated linkages, is introduced. Further evidence is also presented, which indicates that the [M‐RCO2CH2]+ ions arise from the positions 1 and 3 and, in agreement with earlier studies from other laboratories, it is thus possible to identify the acyl groups attached to the 1 and 2 positions of the glyceryl moiety.
Mass spectrometry of triglycerides: II. Specifically deuterated triglycerides and elucidation of fragmentation mechanisms
Authors: Aasen A. J. , Lauer W. M. , Holman R. T.
Published: November 2006

Deuterium labeled monoacid triglycerides were synthesized and their mass spectra were measured. The spectra provided further support for proposed (1) structures of principal ions, knowledge about the formation of [M‐18]+, the interexchange of hydrogen atoms between 2 and the 5,6 or 7 positions and the explusion of part of the alkyl chain.
Sphingolipid long chain bases
Authors: Karlsson Karl‐Anders
Published: November 2006

About 60 natural sphingolipid long chain bases have been identified or proposed. A review is given on their nomenclature, distribution, metabolism, biologic properties, chemistry and methods of characterization.