bluuebunny/crossref_metadata_2025 huggingface dataset:
Phenotypic plasticity of reproductive effort in a colonial ascidian, Botryllus schlosseri
Authors: Newlon Arthur W. , Yund Philip O. , Stewart‐Savage J.
Published: May 2003

Phenotypic plasticity is the capability of a genotype to produce different phenotypes in different environments. Previous studies have indicated phenotypic variability in asexual, male, and female reproduction in Botryllus schlosseri, a hermaphroditic, colonial ascidian, but not explicitly tested for genotype by environment interactions that indicate genetic variation in plastic responses. Consequently, clones derived from an estuarine population were deployed at their native site and a warmer, higher productivity site 10km up‐river. Male reproduction was assayed by testis size, female reproduction by the number of eggs produced, and asexual reproduction by colony growth rate. To test for ontogenetic effects, data were collected from two different generations of zooids born in the field. Analyses of variance indicated plasticity in asexual and female reproduction during the first zooid generation and plasticity in all three traits during the third zooid generation. Reaction norms varied significantly among genotypes in direction and magnitude for asexual reproduction at both times, implying that selection on asexual reproduction is weak. Sperm production during the third zooid generation was significantly lower at the nonnative site, but there was no genotype by environment interaction. The reaction norms for female reproduction varied significantly among genotypes in direction and magnitude during the first zooid generation, but only varied in magnitude during the third generation, with egg production being higher in all genotypes at the nonnative site. Comparisons of weighted frequency distributions between sites demonstrated that differences in egg production in the third generation were due to increases in the proportion of reproductive zooids within a colony. The greater emphasis on female reproduction at a site associated with higher food availability and temperature, and the greater emphasis on male reproduction at a colder, food‐limited site, supports predictions from sex allocation theory. J. Exp. Zool. 297A:180–188, 2003. © 2003 Wiley‐Liss, Inc.
Histological process and dynamics of germ cell degeneration in pejerrey Odontesthes bonariensis larvae and juveniles during exposure to warm water
Authors: Ito Lauro Satoru , Yamashita Michiaki , Strüssmann Carlos Augusto
Published: May 2003

Elevated temperature causes degeneration and disappearance of the germ cells in the males of scrotal mammals. It was recently shown that heat‐induced germ cell degeneration occurs also in fish but, unlike in mammals, it occurs not only in males but also in females. The purpose of this study was to clarify the histological process and dynamics of heat‐induced germ cell disappearance in pejerrey Odontesthes bonariensis larvae and juveniles. Monosex and mixed‐sex fish produced by thermal manipulation of sex (temperature‐dependent sex determination) were subjected to 29°C for periods between 1 and 12 weeks, and used to analyze, by histological methods, the changes in gonadal size and the number of normal and degenerating germ cells. Groups exposed to 29°C for 8–12 weeks were subsequently transferred to 24°C to verify if any gonadal damage would be permanent. Germ cell degeneration, histo‐logically characterized by nuclear pyknosis or eosinophilia and cytoplasmic eosinophilia, was observed with increasing frequency at higher temperatures (29>24> 17°C) and more in males than in females. Clear degenerative changes in the germinal epithelium usually began within one week of exposure to 29°C and appeared clearer in females than in males. Complete loss of germ cells was observed only in individuals exposed for periods of 8–12 weeks to 29°C but no treatment produced 100% sterile fish. Germ cells that remained in the gonads after exposure to 29°C retained the capacity to rapidly recolonize germ cell‐depleted areas, suggesting that the associated somatic cells in the gonads are little or not affected by this temperature. J. Exp. Zool. 297A:169–179, 2003. © 2003 Wiley‐Liss, Inc.
Application of artificial insemination technique to eupyrene and/or apyrene sperm in Bombyx mori
Authors: Sahara Ken , Takemura Yoko
Published: May 2003

The silkworm, Bombyx mori, has a dimorphic sperm system. The eupyrene sperm is the sperm to fertilize eggs and the apyrene sperm plays a crucial role for assisting fertilization. Heat‐treated (33°C for 96h) Daizo (DH) males, one of the strains in the silkworm, produce only eupyrene sperm, while in triploid males only apyrene sperm are functional. Though both types of males are found to be sterile, double copulation of the two males with a single female greatly increases fertility. Here we examined the fertilizing ability of eupyrene and apyrene sperm by means of an artificial insemination technique previously established in B. mori. Neither the eupyrene sperm collected from DH males, nor the apyrene sperm from triploid males have the ability to fertilize eggs. Artificial insemination with the mixture of eupyrene and apyrene sperm leveled up the frequency of fertilized eggs to more than 80%. When cryopreserved DH sperm (eupyrene sperm) were subjected to the same experiment, more than 95% fertilized eggs were obtained. These results confirmed that apyrene sperm play an important and indispensable role in fertilization in B. mori. Separate collection of functional eupyrene sperm and functional apyrene sperm and success of fertilization by means of the artificial insemination technique are applicable for further studies to elucidate the function of apyrene sperm. J. Exp. Zool. 297A:196–200, 2003. © 2003 Wiley‐Liss, Inc.
Detailed lipid analysis of yolk platelets of amphibian (Bufo arenarum) oocytes
Authors: Buschiazzo Jorgelina , Bruzzone Ariana , Alonso Telma Susana
Published: May 2003

Yolk platelets, the principal components of amphibian oocytes, have been generally considered as material reservoirs. Their biochemical composition and function during oogenesis and early development have not been fully elucidated. The aim of this study was to carry out a lipidic characterization of yolk platelets from full‐grown Bufo arenarum oocytes. Ovarian oocytes were manually obtained and the subcellular fraction was isolated by centrifugation at low velocity. Lipids were separated by thin‐layer chromatography. For compositional analysis, they were derived by methanolysis, being identified and quantified in a gas‐liquid chromatograph. Phospholipid content indicates that phosphatidylcholine and phosphatidylethanolamine are the main phospholipids followed by phosphatidylinositol, sphingomyelin, phosphatidylserine, and phosphatidic acid. Phospholipidic profile is similar to that in whole oocytes except for the absence of diphosphatidylglycerol in yolk platelets. Oleic, palmitic, and linoleic acids are the main fatty acids in phosphatidylcholine, and oleic acid is the principal one in phosphatidylethanolamine. In phosphatidic acid, palmitic, estearic, palmitoleic, and oleic acids represent 68 mol% of the total acyl groups. Phosphatidylinositol, enriched in arachidonic acid, is the most unsaturated phospholipid while sphingomyelin shows the lowest unsaturation index. The acyl group distribution in triacylglycerols is similar when yolk platelets and whole oocytes are compared. Polar and neutral lipids of yolk platelets determine the lipidic profile of the whole oocyte. The presence of unusual fatty acids as 14:0, 15:0, 15:1, 17:0, and 17:1 in phospholipids and triacylglycerols may indicate an oxidation mechanism different from β‐oxidation in yolk platelets and/or a structural and functional relation with mitochondria. Given that yolk platelets in amphibian oocytes may act in a dynamic fashion in development, their role should be reconsidered. J. Exp. Zool. 297A:189–195, 2003. © 2003 Wiley‐Liss, Inc.
Morphology and escape performance of tiger salamander larvae (Ambystoma tigrinum mavortium)
Authors: Fitzpatrick Benjamin M , Benard Michael F. , Fordyce James A.
Published: May 2003

The ability of an individual to escape predators is an important component of fitness. Several adaptive explanations of body shape variation in amphibians hypothesize relationships between swimming performance and morphology, but these ideas have rarely been tested. Here we investigate bivariate and multivariate relationships between natural variation in morphology and performance. We used high‐speed video to examine fast‐starts associated with escape responses in small tiger salamander larvae (Ambystoma tigrinum). Our results indicate that performance is influenced by interactions among aspects of morphology, physiology, and behavior. Relationships between morphometric variables and velocity could be detected with multivariate, but not bivariate statistical analyses. In particular, relationships between morphology and velocity depend on tail beat frequency (potentially a measure of effort or vigor). Relationships between morphology and acceleration were detected with bivariate analyses, but multivariate analysis suggests that acceleration performance, too, depends on interactions between morphology and tail beat frequency. We found a positive relationship between tail area and propulsive performance, which supports adaptive interpretations of variation in larval tail shape within and between amphibian species. J. Exp. Zool. 297A:147–159, 2003. © 2003 Wiley‐Liss, Inc.
Melatonin enhances the sensitivity of circadian pacemakers to light in the nocturnal field mouse Mus booduga
Authors: Sharma Vijay Kumar , Chidambaram R. , Yadunandam A. Kasin
Published: May 2003

The effect of exogenous melatonin (1 mg/kg) on light pulse (LP) induced phase shifts of the circadian locomotor activity rhythm was studied in the nocturnal field mouse Mus booduga. Three phase response curves (PRCs: LP, control, and experimental) were constructed to study the effect of co‐administration of light and melatonin at various circadian times (CTs). The LP PRC was constructed by exposing animals free‐running in constant darkness (DD) to LPs of 100–lux intensity and 15–min duration, at various CTs. The control and experimental PRCs were constructed by using a single injection of either 50% DMSO or melatonin (1 mg/kg dissolved in 50% DMSO), respectively, administered 5 min before LPs, to animals free‐running in DD. A single dose of melatonin significantly modified the waveform of the LP PRC. The experimental PRC had significantly larger areas under advance and delay regions of the PRC compared to the control PRC. This was also confirmed when the phase shifts obtained at various CTs were compared between the three PRCs. The phase delays at three phases (CT12, CT14, and CT16) of the experimental PRCs were significantly greater than those of the control and the LP PRCs. Based on these results we conclude that phase shifting effects of melatonin and light add up to produce larger responses. J. Exp. Zool. 297A:160–168, 2003. © 2003 Wiley‐Liss, Inc.
Gastropod ontogenetic torsion: Developmental remnants of an ancient evolutionary change in body plan
Authors: Page Louise R.
Published: May 2003

A dramatic morphogenetic movement (‘ontogenetic torsion’) during the development of gastropods has been proposed as a recapitulation of the original developmental departure that established the novel gastropod body plan. Nevertheless, speculative literature about ontogenetic torsion and its evolutionary significance has far outstripped empirical observations and recent results suggest that the developmental process may be somewhat different than the traditional description. I used scanning electron microscopy, immunohistochemistry, phalloidin labeling, and histological sections to monitor displacements of five components of the visceropallium with respect to axial coordinates of the cephalopodium in developing embryos of the caenogastropod, Trichotropis cancellata. Embryos of this species achieve a transient stage of anatomical organization that also arises during development of a vetigastropod (Haliotis kamtschatkana), although morphogenetic processes that generate this stage are different in these two species. At the stage of similarity, the embryonic shell has achieved its definitive orientation with respect to the cephalopodium, but the developing mantle cavity, sensory osphradium, and anus are confined to the right side. I also show that this stage of anatomical organization is recognizable during the development of other gastropods, which collectively represent three major gastropod clades. I propose that ontogenetic torsion should be viewed as a conserved stage of anatomical organization during development, rather than a conserved process of 180° rotation between the visceropallium and cephalopodium. The results lead to the suggestion that the mantle cavity of extant gastropods evolved by enlargement of the right side of the mantle cavity in a monoplacophoran‐like ancestor. Under this interpretation, there is no need for a hypothetical pre‐gastropod with a mantle cavity that was restricted to the posterior end. J Exp. Zool (Mol. Dev. Evol.) 297B:11–26, 2003. © 2003 Wiley‐Liss, Inc.
Phylogenetic considerations of clonality, coloniality, and mode of germline development in animals
Authors: Blackstone Neil W. , Jasker Bryan D.
Published: May 2003

The hypothesis that individuality is a derived trait in animals (Buss, '87, The Evolution of Individuality, Princeton, NJ: Princeton University Press; Michod, '99, Darwinian Dynamics, Princeton, NJ: Princeton University Press) can be further tested by a “tree‐based” analysis utilizing a comparative methodology and recent phylogenies. We conducted a maximum parsimony analysis in which we mapped character states for clonality, coloniality, and mode of germline development onto four recent phylogenetic hypotheses (Peterson and Eernisse, 2001, Evol Dev 3:170–205). Clonality appears to be a shared primitive character for metazoans. Coloniality, on the other hand, is a derived trait found in relatively few phyla. The germline appears to have been derived at or near the origin of the first bilaterians. The stem‐lineage metazoan thus appears to have been a clonal, acolonial organism that exhibited somatic embryogenesis. The stem‐lineage bilaterian also was likely clonal and acolonial. Nevertheless, this lineage likely exhibited preformation, i.e., its germline was determined during embryonic development. In addition to supporting the hypothesis that the germline is a derived feature in animals, this analysis is relevant to current debates concerning the nature of the latest common ancestor of the bilaterians. J. Exp. Zool. (Mol. Dev. Evol.) 297B: 35–47, 2003. © 2003 Wiley‐Liss, Inc.
Origin of archosaurian integumentary appendages: The bristles of the wild turkey beard express feather‐type β keratins
Authors: Sawyer Roger H. , Washington Lynette D. , Salvatore Brian A. , Glenn Travis C. , Knapp Loren W.
Published: May 2003

The discovery that structurally unique “filamentous integumentary appendages” are associated with several different non‐avian dinosaurs continues to stimulate the development of models to explain the evolutionary origin of feathers. Taking the phylogenetic relationships of the non‐avian dinosaurs into consideration, some models propose that the “filamentous integumentary appendages” represent intermediate stages in the sequential evolution of feathers. Here we present observations on a unique integumentary structure, the bristle of the wild turkey beard, and suggest that this non‐feather appendage provides another explanation for some of the “filamentous integumentary appendages.” Unlike feathers, beard bristles grow continuously from finger‐like outgrows of the integument lacking follicles. We find that these beard bristles, which show simple branching, are hollow, distally, and express the feather‐type β keratins. The significance of these observations to explanations for the evolution of archosaurian integumentary appendages is discussed. J. Exp. Zool. (Mol. Dev. Evol.) 297B: 27–34, 2003. © 2003 Wiley‐Liss, Inc.
Structure and evolution of the Teleost extraretinal rod‐like opsin (errlo) and ocular rod opsin (rho) genes: Is teleost rho a retrogene?
Authors: Bellingham James , Tarttelin Emma E. , Foster Russell G. , Wells Dominic J.
Published: May 2003

In Teleost fish examined to date the ocular rod opsin gene, rho, is intronless, unlike the rod opsin genes of other vertebrate classes which possess a five exon/four intron structure. We have examined in silico the structure of rho (which is expressed uniquely in the retina) and the closely related extraretinal rod‐like opsin (exo‐rhodopsin) gene, errlo (which is expressed uniquely in the pineal), in the puffer‐fish, Fugu rubripes (Takifugu rubripes). Whilst the ocular rho is intronless in common with other Teleosts, the pineal errlo has the five exon/four intron structure common to the rod opsin gene of other vertebrates. A comparison of the sequence surrounding the errlo and rho loci indicates that the errlo locus is syntenic with RHO, the human rod opsin gene, rather than rho. We suggest that the intronless rho may have arisen through an ancient retrotransposition of a mature mRNA originating from errlo. This duplication event has occurred early in the evolution of the Actinopterygii (ray‐finned fish) since the rho of the primitive Actinopterygians such as sturgeon, bowfin, and gar is also intronless. Since it appears that the intron containing errlo is the ancestral opsin gene that gave rise to the intronless rho in the Teleostei, errlo is therefore the true orthologue of the rod opsin gene in other vertebrate classes. We suggest that loss of expression of errlo in the retina could be related to the metabolic and physiological advantages, such as a reduction in splicing events during RNA processing, that may be conferred through possession of an additional, intronless rod opsin gene in the form of rho. J. Exp. Zool. (Mol. Dev. Evol.) 297B: 1–10, 2003. © 2003 Wiley‐Liss, Inc.
Developmental basis of evolutionary digit loss in the Australian lizard Hemiergis
Authors: Shapiro Michael D. , Hanken James , Rosenthal Nadia
Published: May 2003

Loss of limb skeletal elements is a recurring theme in tetrapod evolution, but the developmental mechanisms underlying this phenomenon remain largely unknown. The Australian lizard genus Hemiergis offers an excellent model system to study limb reduction among closely related, naturally occurring populations with different numbers of digits. Evolutionary digit loss in Hemiergis does not result from simple truncation of a pentadactyl skeletal developmental program. Rather, the duration of embryonic expression of the patterning molecule Sonic hedgehog (SHH) is shortened in limbs with reduced numbers of digits, and is correlated with decreased cell proliferation in the posterior aspect of the limb. Moreover, this comparative analysis suggests an early role for SHH in specification of digit identity and later importance in maintaining cell proliferation and survival. Subtle changes in spatial or temporal regulation of SHH may alter proliferation and patterning of the developing limb, thereby effecting divergence in adult limb morphology among closely related species. In contrast, expression of MSX and Distal‐less proteins were similar among embryos from different populations. J. Exp. Zool. (Mol. Dev. Evol.) 297B:48–56, 2003. © 2003 Wiley‐Liss, Inc.
Neural expression of the Huntington's disease gene as a chordate evolutionary novelty
Authors: Kauffman Jeffrey S. , Zinovyeva Anna , Yagi Kasumi , Makabe Kazuhiro W. , Raff Rudolf A.
Published: May 2003

Huntington's disease is a progressive neuro‐degenerative disorder in humans, which is scharacterized by onset of dementia, muscular ataxia, and death. Huntington's disease is caused by the expansion of the polyglutamine (polyQ) tract in the N‐terminus of the HD protein (Huntingtin). CAG expansion is a dominant gain of function mutation that affects striated neurons in the brain (Cattaneo, 2003, News Physiol Sci 18:34). The evolutionary origins of the vertebrate Hd gene are not well understood. In order to address the evolutionary history of the Hd gene, we have cloned and characterized the expression of the Hd gene in two invertebrate deuterostomes, an echinoderm and an ascidian, and have examined the expression patterns in a phylogenetic context. Echinoderms are basal deuterostomes and ascidians are basal chordates; both are useful for understanding the origins of and evolutionary trends in genes important in vertebrates such as the Huntigton's disease gene. Expression of Hd RNA is detected at all stages of development in both the echinoderm and ascidian studied. In the echinoderm Heliocidaris erythrogramma, Hd is expressed in coelomic mesodermal tissue derivatives, but not in the central nervous system. In the ascidian Halocynthia roretzi expression is located in both mesoderm and nervous tissue. We suggest that the primitive deuterostome expression pattern is not neural. Thus, neural expression of the Hd gene in deuterostomes may be a novel feature of the chordate lineage, and the original role(s) of HD in deuterostomes may have been non‐neural. J. Exp. Zool. (Mol. Dev. Evol.) 297B:57–64, 2003. © 2003 Wiley‐Liss, Inc.
Production of volatile compounds by hairy root cultures of Cichorium intybus L under the influence of fungal elicitors and their analysis using solid‐phase micro extraction gas chromatography–mass spectrometry
Authors: Bais Harsh Pal , Dattatreya BS , Ravishankar GA
Published: May 2003

Hairy root cultures of Cichorium intybus L produced volatile aromatic compounds under the influence of fungal elicitors. It was observed that the intensity of the production of volatile aromatic compounds in the hairy root cultures of C intybus with 10 ml l−1 media filtrate (MF) of Phytopthora parasitica var nicotiana reached a maximum on the 21st day, as seen by a quantitative flavour profiling method. It was noted that, during the time course, treatment with 10 ml l−1 MF of P parasitica to the MS basal liquid medium containing hairy root cultures of chicory resulted in changed root morphology with cell wall thickening and shear. The components of the volatile aromatic compounds were identified as a propyl isovalerate, undecanal, nonanol, isoamyl nonanoate and 2‐decene‐1‐ol. The mass spectra of all these compounds matched well with the NIST/EPA/NIH library and by comparing with the Kovats index of volatile compounds. The major fruity note was due to the presence of two of the major volatile components, namely propyl isovalerate and isoamyl nonanoate, which were also produced at higher concentration on day 21. This response of chicory hairy root cultures to the fungal elicitor producing volatile aromatic compounds would imply eco‐physiological functions, possibly for plant defence system. Copyright © 2003 Society of Chemical Industry
Antioxidant activity screening of extracts from Sideritis species (Labiatae) grown in Bulgaria
Authors: Koleva Irina I , Linssen Jozef PH , van Beek Teris A , Evstatieva Lyuba N , Kortenska Vessela , Handjieva Nedyalka
Published: May 2003

Plant samples from several species and populations of the genus Sideritis (Labiatae) grown in Bulgaria (S scardica, S syriaca and S montana) were extracted with different solvents. Their antioxidant activities were determined by the β‐carotene bleaching test (BCBT), 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH•) radical scavenging method and static headspace gas chromatography (HS‐GC) and compared with the antioxidant activity of two reference compounds of different polarity, viz butylated hydroxytoluene (BHT) and rosmarinic acid. The pure reference compounds were applied in a ten‐times lower concentration than the plant extracts. The highest antioxidant activity in the BCBT, close to that of BHT, was observed for the more apolar extracts. The inhibitory effect on β‐carotene bleaching of the polar extracts and rosmarinic acid was much lower than that of BHT. The inhibition of hexanal formation in bulk safflower oil by most of S syriaca and S scardica extracts was as effective as BHT but less so than rosmarinic acid. S montana extracts showed weak antioxidant or even pro‐oxidant properties. Extracts from butanol and from ethyl acetate and the total methanol extracts from all Sideritis plants studied showed a strong radical scavenging activity against DPPH•, close to that of rosmarinic acid. S montana extracts were, as a whole, slightly weaker radical inhibitors than the extracts from the other two species. The antioxidant activity of Sideritis extracts was attributed to the presence of flavonoid and phenylpropanoid glycosides. Copyright © 2003 Society of Chemical Industry
Change in α‐tocopherol contents, lipid oxidation and fatty acid profile in eggs enriched with linolenic acid or very long‐chain ω3 polyunsaturated fatty acids after different processing methods
Authors: Cortinas Lucía , Galobart Jaume , Barroeta Ana C , Baucells María D , Grashorn Michael A
Published: May 2003

The influences of dietary supplementation with α‐tocopheryl acetate (α‐TA) and of processing (by hard‐boiling and scrambling) of eggs enriched with ω3 fatty acids, either very long‐chain ω3 polyunsaturated fatty acids (VLC ω3 PUFAs) or linolenic acid (LNA), on fatty acid composition, α‐tocopherol content and lipid oxidation (thiobarbituric acid (TBA) values) were studied. Four dietary treatments were formulated from a basal diet containing 40 g kg−1 linseed oil (LO) or fish oil (FO) combined with either 0 or 100 mg α‐TA kg−1 of feed. Eggs from LO treatments were enriched with LNA and those from FO treatments were rich in VLC ω3 PUFAs. Neither processing nor dietary supplementation with α‐TA modified greatly the fatty acid profile of eggs. Dietary supplementation with α‐TA increased the α‐tocopherol content of eggs (187.2 versus 407.9 µg g−1 dry matter). Eggs from FO treatments showed lower α‐tocopherol content than those from LO treatments (273.5 versus 321.6 µg g−1 dry matter), and processing of eggs enriched with VLC ω3 PUFA reduced the α‐tocopherol content by a significant 16%. Moreover, processing of eggs increased lipid oxidation two‐ to nine‐fold. Oxidation levels of hard‐boiled eggs were 30.4% higher than those of scrambled eggs. TBA values in hard‐boiled and scrambled eggs were significantly reduced when 100 mg α‐TA kg−1 of feed supplemented the diet only in those eggs enriched with VLC ω3 PUFA (from FO treatments). Copyright © 2003 Society of Chemical Industry
Monitoring of seed composition of prickly pear (Opuntia ficus‐indica L) fruits during maturation period
Authors: Coşkuner Yalçı n , Tekin Aziz
Published: May 2003

Prickly pear fruit seeds were subjected to a range of chemical analyses during their 15 week maturation period. Seeds contained on average 71.5 g kg−1 dry matter, 61.9 g kg−1 crude oil, 9.4 g kg−1 protein, 507.4 g kg−1 crude fibre, 12.3 g kg−1 ash and 409.0 g kg−1 carbohydrate. The fatty acid composition of prickly pear seed oil consisted of 1.3–1.9 g kg−1 myristic (14:0), 132.1–156.0 g kg−1 palmitic (16:0), 14.4–18.5 g kg−1 palmitoleic (16:1), 33.1–47.9 g kg−1 stearic (18:0), 210.5–256.0 g kg−1 oleic (18:1), 522.5–577.6 g kg−1 linoleic (18:2), 2.9–9.7 g kg−1 linolenic (18:3), 4.2–6.6 g kg−1 arachidic (20:0) and 2.1–3.0 g kg−1 behenic (22:0) acids, which is comparable with that of corn oil. No statistical difference in seed weight ratio was determined during the maturation period, whereas changes in the saturated fatty acids of the seed oil were observed. From this study it can be concluded that the seeds of prickly pear are suitable as animal feed. Copyright © 2003 Society of Chemical Industry
Specific determination of cysteine in human urine by capillary micellar electrokinetic chromatography
Authors: Ševčíková Petra , Glatz Zdeněk
Published: June 2003

This paper describes a method for the analysis of cysteine in human urine using capillary micellar electrokinetic chromatography and on‐column reaction with 2,2′‐dipyridyl disulfide. In this reaction cysteine is quantitatively transformed into a mixed disulfide concomitantly with formation of an equimolar amount of 2‐thiopyridone that is further separated by capillary micellar electrokinetic chromatography and determined spectrophotometrically at 343 nm. The concentration of cysteine is thus estimated indirectly from the result of 2‐thiopyridone determination. The linear detection range for concentration versus peak area for the assay is from 0.05 to 5 mM (correlation coefficient 0.989) with a detection limit of 2.5 μM and a limit of quantitation of 8.5 μM. The inter‐day reproducibility of the peak area was 2.18% and the inter‐day reproducibility of the migration time 0.51%. The method is relatively rapid, simple, and can be easily automated. Moreover, its detection limit covers the concentration range at which cysteine is present in biological samples such as human urine.
SPME – A valuable tool for investigation of flower scent
Authors: Barták Petr , Bednář Petr , Čáp Lubomír , Ondráková Lenka , Stránský Zdeněk
Published: June 2003

A novel Headspace Solid Phase Microextraction (HS‐SPME) protocol is proposed for the analysis of floral scent. Volatile compounds emitted from the flower are collected on a Carboxen/PDMS fiber for 1 hour, transferred to the GC, and analyzed by GC/MS. The method completely eliminates the use of organic solvents, does not require special instrumentation, and may readily be performed in the field without access to mains electricity and other energy supplies. The method is robust, sensitive, and reduces the sampling stress on the investigated plant. Since enzymatic reactions in living flowers may cause changes in the composition of emitted fragrance, dried rosemary (Rosmarinus officinalis L.) was used as a stable standard for the method development and optimization. In addition, grape wine was also suggested as homogeneous, bio‐compatible, and relatively stable standard of pronounced and typical scent for the same purpose. The optimized method was used for the comparative investigation of the fragrances emitted by two different species – Lathyrus vernus (L.) and Orchis pallens (L.). Several monoterpenes (C10 compounds) were found as the main fragrance components of lathyrus, while sesquiterpenes (C15 compounds) were typical for the orchid.
Determination of the purity of phenoxymethylpenicillin by micellar electrokinetic chromatography and reversed phase liquid chromatography on a monolithic silica column
Authors: Doležalová Milada , Čápová Hana , Jobánek Roman
Published: June 2003

A micellar electrokinetic chromatographic and a fast reversed‐phase liquid chromatographic method have been developed for determination of the purity of phenoxymethylpenicillin. The optimized running buffer composition was 40 mM phosphate–borate–125 mM SDS–3.5% (v/v) methanol. The HPLC method employed a monolithic silica C18 column and a mobile phase composed of phosphate buffer, pH 3.5, and ACN, the flow‐rate being 3.5 mL/min. Both methods were successfully validated. Linearity, intermediate precision, limits of quantitation, accuracy, and a good correlation of the HPLC and MEKC results were demonstrated. Both methods proved to be fast and reliable and sufficiently sensitive. A combination of the two methods can be very useful in impurity profiling.
Photooxidation and Photoconductivity of Polyferrocenylsilane Thin Films
Authors: Cyr Paul W. , Tzolov Marian , Manners Ian , Sargent Edward H.
Published: June 2003

Irradiation of thin films of poly(ferrocenylmethylphenylsilane) ([Fe(η5‐C5H4)2SiMePh]n) cast from chloroform solution with UV light leads to photooxidation of ferrocene centers in the polymer main chain. The extent of the polymer oxidation can be controlled in the range ca. 0–5% by the duration of the irradiation exposure and by the concentration of chloroform. The photooxidized polyferrocenylsilane material is conductive, with an increased conductivity of greater than three orders of magnitude relative to the unoxidized material. In addition, the photooxidized polymers have been found to be photoconductive. The photooxidation process can be reversed by means of chemical reduction using hydrazine or decamethylferrocene, leading to the regeneration of the neutral polymers. However, substantial molecular weight decline was detected during the photooxidation/reduction process, presumably as a result of chain cleavage reactions induced by the anionic or radical chlorinated photoproducts. Methylation of the cyclopentadienyl rings of the ferrocene moiety in the polymer was found to lead to materials which are significantly more stable.

Time trace of the current at constant applied voltage of 100 V for a PFS film upon illumination. The ON and OFF states were created by using a mechanical shutter.

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Time trace of the current at constant applied voltage of 100 V for a PFS film upon illumination. The ON and OFF states were created by using a mechanical shutter.
Synthesis of New Hydrogels by Copolymerization of Poly(2‐methyl‐2‐oxazoline) Bis(macromonomers) and N‐Vinylpyrrolidone
Authors: Rueda Juan C. , Komber Hartmut , Cedrón Juan C. , Voit Brigitte , Shevtsova Galina
Published: June 2003

New non‐ionic hydrogels were synthesized by radical homopolymerization of vinyl end‐functionalized poly(2‐methyl‐2‐oxazoline) bis(macromonomers), or by radical copolymerization of these bis(macromonomers) with N‐vinyl‐2‐pyrrolidone (NVP). The poly(2‐methyl‐2‐oxazoline) bis(macromonomers) were synthesized through “living” cationic ring‐opening polymerization of 2‐methyl‐2‐oxazoline (MeOXA), using, simultaneously, the known “initiating” and “end‐capping” method for synthesis of macromonomers. Chloromethyl styrene was used as initiator and N‐(4‐vinylbenzyl)‐piperazine was used as the terminating agent. Well defined poly(2‐methyl‐2‐oxazoline) bis(macromonomers) were obtained with Pn = 4, 11, and 17. The hydrogel structures were characterized by high‐resolution magic angle spinning NMR technique and their solvent absorption capacity was tested by swelling experiments in different solvents. The bis(macromonomers) were characterized by NMR spectroscopy and gel permeation chromatography.

Schematic of polymerization

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Schematic of polymerization
Deformation Behavior of PET, PBT and PBT‐Based Thermoplastic Elastomers as Revealed by SAXS from Synchrotron
Authors: Stribeck Norbert , Fakirov Stoyko , Apostolov Anton A. , Denchev Zlatan , Gehrke Rainer
Published: June 2003

The present paper discloses the changes in the nanostructure as revealed by small‐angle X‐ray scattering (SAXS) of synchrotron radiation of anisotropic semi‐crystalline samples of polyester and poly(ether ester) type differing in their chemical composition, while subjected to controlled progressive elongation. From the group of polyesters poly(ethylene terephthalate) (PET), and poly(butylene terephthalate) (PBT) were selected. Two PBT‐based commercial poly(ether ester)s were also studied differing in the molecular weight of their soft segments (poly(tetramethylene glycol), PTMG) being 1000 and 2000, respectively. A blend of PBT and EM550 (40/60 by wt.) was also characterized. All materials underwent the same sample preparation process resulting in highly oriented “bristles” of 1 mm diameter. It was found that εb, the elongation at break, strongly depends on the flexibility of the glycol residues of the materials studied – ranging from εb = 8% for PET that contains ethylene glycol residues, through εb = 18% for PBT including the more flexible tetramethylene glycol (TMG) up to εb = 510% for the PEE containing the longest PTMG moieties. During straining the relationship between the external elongation ε and the changes in the long spacing L was determined. After relaxation from each deformation step the relationship between the tensile set εr and the long period L was also followed and discussed. Such analysis led to a model describing the nanostructure evolution during the deformation‐relaxation cycle that finally was verified and refined utilizing the multidimensional chord distribution function computed from the anisotropic SAXS patterns.

2D SAXS patterns (pseudo color) of bristles of PET (PBT), respectively, cold drawn, λ = 3.5 (λ = 2.3) and annealed with fixed ends for 6 h at 240 °C (180 °C), recorded at room temperature at a forced tensile deformation ε or tensile set (residual elongation) εr in percent.

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2D SAXS patterns (pseudo color) of bristles of PET (PBT), respectively, cold drawn, λ = 3.5 (λ = 2.3) and annealed with fixed ends for 6 h at 240 °C (180 °C), recorded at room temperature at a forced tensile deformation ε or tensile set (residual elongation) εr in percent.
Hyperbranched Polyalkoxysiloxanes via AB3‐Type Monomers
Authors: Jaumann Manfred , Rebrov Eugene A. , Kazakova Valentina V. , Muzafarov Aziz M. , Goedel Werner A. , Möller Martin
Published: June 2003

We have synthesized polyethoxysiloxanes starting from the AB3‐type monomers triethoxysilanol and acetoxytriethoxysilane. The polymers are liquid and soluble in organic solvents.29Si NMR spectroscopy and MALDI‐ToF mass spectrometry analyses show that the polymers have a hyperbranched structure with additional internal cyclization.29Si NMR spectroscopy indicates that the polymer synthesized from acetoxytriethoxysilane is less branched than the polymer synthesized from triethoxysilanol. Analysis of the molar mass and mass distribution of the polymers via size exclusion chromatography (calibrated via MALDI‐ToF MS and viscosimetry) yields a molar mass ofMn ≈ 2 kg · mol−1andMw ≈ 8 kg · mol−1for polymers synthesized from triethoxysilanol. The molar mass of the polymers synthesized from acetoxytriethoxysilane can be controlled by variation of the polymerization time in the range ofMn ≈ 1.8–12 kg · mol−1andMw ≈ 2.1–2 200 kg · mol−1.

Photograph of a vial containing polyethoxysiloxane obtained from triethoxysilanol and a schematic drawing of the proposed molecular structure of the polymer.

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Photograph of a vial containing polyethoxysiloxane obtained from triethoxysilanol and a schematic drawing of the proposed molecular structure of the polymer.
Poly(ethylene oxide)‐ and Poly(perfluorohexylethyl methacrylate)‐Containing Amphiphilic Block Copolymers: Association Properties in Aqueous Solution
Authors: Hussain Hazrat , Busse Karsten , Kressler Jörg
Published: June 2003

Amphiphilic di‐ and triblock copolymers containing poly(ethylene oxide) (PEO) as the hydrophilic block and poly(perfluorohexylethyl methacrylate) (PFMA) as the hydrophobic block were synthesized by atom‐transfer radical polymerization using hydroxy‐terminated PEO as the macroinitiator. The copolymers were characterized by size exclusion chromatography and 1H NMR spectroscopy. Self‐association in aqueous solution has been investigated using surface tension measurements, dynamic light scattering (DLS), and transmission electron microscopy (TEM). From surface tension measurements in water, a characteristic concentration (c*) can be detected, which is interpreted as the critical micelle concentration (cmc). The cmc decreases with an increase in fluoro content in the triblock copolymer up to 11 wt.‐% PFMA (solubility limit). DLS studies have been carried out for different samples above the cmc, showing small aggregates (micelles) and single chains for diblock copolymer solutions. In the case of triblock copolymers large clusters were the dominant aggregates in addition to the micelles and single chains. The effect of temperature and concentration on the micelle and cluster formation has been investigated by DLS. Micelle size was found to be resistant to any change by temperature, however, a slight but significant increase in apparent hydrodynamic radius was observed with an increase in concentration, while both temperature and concentration affected the formation of large clusters, especially in concentrated solutions. TEM has been carried out to visualize the morphology of the aggregates after transferring the solution to carbon film. The initial concentration for the preparation of TEM samples was found to have a strong influence on the morphology of the aggregates. By adding colloidal gold particles to the solutions, the typical covering by the polymer was observed by TEM.

Decay‐rate distributions for PEO10F5 (4.0 g · L−1); obtained from the time correlation functions.

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Decay‐rate distributions for PEO10F5 (4.0 g · L−1); obtained from the time correlation functions.
Lack of association between progressive supranuclear palsy and arterial hypertension: A clinicopathological study
Authors: Colosimo Carlo , Osaki Yasushi , Vanacore Nicola , Lees Andrew J.
Published: May 2003

It has been reported that up to 80% of patients clinically diagnosed as having progressive supranuclear palsy (PSP) may have arterial hypertension (HT). Because previous studies were performed on patients with presumed diagnosis of PSP, we tried to replicate these studies in a series of pathologically confirmed patients. Seventy‐three patients with a neuropathological diagnosis of PSP autopsied at the Queen Square Brain Bank for Neurological Disorders in London were collected between 1989 and 1999. For the purpose of this study, patients were considered hypertensive if a blood pressure above 140/90 mm Hg was found in the clinical records. The prevalence of HT in PSP patients at the first and at the last visit during their neurological disease was compared with that found in a series of 21 normal controls who donated their brain to the same institution. Overall, 29 of 73 (39.7%) of the patients were recorded as having HT at the first visit during the disease course; this ratio increased to 42 of 73 (57.5%) at the last visit before death. When these figures were compared to the 21 normal controls (11 of 21 with HT, 52.4%), we were unable to find an increased prevalence of HT in PSP (odds ratio, 0.60; 95% confidence interval, 0.20–1.76). Therefore, HT does not represent an important clinical feature of this neurodegenerative disorder, although cerebrovascular disease can masquerade clinically as PSP. © 2003 Movement Disorder Society
Development and testing of the Parkinson's disease quality of life scale
Authors: Welsh Mickie , McDermott Michael P. , Holloway Robert G. , Plumb Sandy , Pfeiffer Ronald , Hubble Jean
Published: May 2003

We report on the development and results of preliminary psychometric testing of a disease specific health‐related quality of life (HRQoL) scale intended for use in individuals diagnosed with idiopathic Parkinson's disease (PD). Results from an initial qualitative study provided content for item development and scale construction of the Parkinson's disease quality of life scale (PDQUALIF). The 33‐item instrument includes seven domains: social/role function, self‐image/sexuality, sleep, outlook, physical function, independence, and urinary function, plus one item of Global HRQoL. Initial psychometric testing of the instrument was conducted in 233 outpatient clinic attendees with physician‐confirmed idiopathic PD. Factor structure, reliability and validity of the scale have been established in this cross‐sectional study. Continuing development of the PDQUALIF will be directed at enhancing the psychometric properties, establishing responsiveness and determining appropriateness in culturally diverse samples. © 2003 Movement Disorder Society
Cholecystokinin antagonists: Pharmacological and therapeutic potential
Authors: Herranz Rosario
Published: May 2003

Cholecystokinin (CCK) is a regulatory peptide hormone, predominantly found in the gastrointestinal tract, and a neurotransmitter present throughout the nervous system. In the gastrointestinal system CCK regulates motility, pancreatic enzyme secretion, gastric emptying, and gastric acid secretion. In the nervous system CCK is involved in anxiogenesis, satiety, nociception, and memory and learning processes. Moreover, CCK interacts with other neurotransmitters in some areas of the CNS. The biological effects of CCK are mediated by two specific G protein coupled receptor subtypes, termed CCK1 and CCK2. Over the past fifteen years the search of CCK receptor ligands has evolved from the initial CCK structure derived peptides towards peptidomimetic or non‐peptide agonists and antagonists with improved pharmacokinetic profile. This research has provided a broad assortment of potent and selective CCK1 and CCK2 antagonists of diverse chemical structure. These antagonists have been discovered through optimization programs of lead compounds which were designed based on the structures of the C‐terminal tetrapeptide, CCK‐4, or the non‐peptide natural compound, asperlicin, or derived from random screening programs. This review covers the main pharmacological and therapeutic aspects of these CCK1 and CCK2 antagonist. CCK1 antagonists might have therapeutic potential for the treatment of pancreatic disorders and as prokinetics for the treatment of gastroesophageal reflux disease, bowel disorders, and gastroparesis. On the other hand, CCK2 antagonists might have application for the treatment of gastric acid secretion and anxiety disorders. © 2003 Wiley Periodicals, Inc. Med Res Rev, 23, No. 5, 559–605, 2003
Protease inhibitors of the sulfonamide type: Anticancer, antiinflammatory, and antiviral agents
Authors: Supuran Claudiu T. , Casini Angela , Scozzafava Andrea
Published: May 2003

The sulfonamides constitute an important class of drugs, with several types of pharmacological agents possessing antibacterial, anticarbonic anhydrase, diuretic, hypoglycemic, and antithyroid activity among others. A large number of structurally novel sulfonamide derivatives have ultimately been reported to show substantial protease inhibitory properties. Of particular interest are some metalloprotease inhibitors belonging to this class, which by inhibiting several matrix metalloproteases (MMPs) show interesting antitumor properties. Some of these compounds are currently being evaluated in clinical trials. The large number of sulfonamide MMP inhibitors ultimately reported also lead to the design of effective tumor necrosis factor‐α converting enzyme (TACE) inhibitors, potentially useful in the treatment of inflammatory states of various types. Since both MMPs and TACE contribute synergistically to the pathophysiology of many diseases, such as arthritis, bacterial meningitis, tumor invasion; the dual inhibition of these enzymes emerged as an interesting target for the drug design of anticancer/antiinflammatory drugs, and many such sulfonamide derivatives were recently reported. Human neutrophyl elastase (HNE) inhibitors of the sulfonamide type may also be useful in the treatment of inflammatory conditions, such as emphysema, cystic fibrosis, chronic bronchitis, ischemia reperfusion injury, and acute respiratory distress syndrome. Inhibition of some cysteine proteases, such as several caspase and cathepsin isozymes, may lead to the development of pharmacological agents effective for the management of several diseases, such as rheumatoid arthritis, inflammatory bowel disease, brain damage, and stroke. Another research line that progressed much in the last time regards different sulfonamides with remarkable antiviral activity. Some clinically used HIV protease inhibitors (such as amprenavir) possess sulfonamide moieties in their molecules, which are critical for the potency of these drugs, as shown by means of X‐ray crystallography, whereas a very large number of other derivatives are constantly being synthesized and evaluated in order to obtain compounds with lower toxicity or augmented activity against viruses resistant to the such first generation drugs. Other viral proteases, such as those isolated from several types of herpes viruses may be inhibited by sulfonamide derivatives, leading thus to more effective classes of antiviral drugs. © 2003 Wiley Periodicals, Inc. Med Res Rev, 23, No. 5, 535–558, 2003