bluuebunny/crossref_metadata_2025 huggingface dataset:
SPERM BUNDLE‐FEMALE SOMATIC CELL INTERACTION IN THE FERTILIZATION PROCESS OF VOLVOX CARTERI F. WEISMANNIA(CHLOROPHYTA)1
Authors: Coggin Steven J. , Hutt William , Kochert Gary
Published: December 2004

We studied the fertilization reaction in Volvox carter f. weismannia (Powers) Iyengar. Tests for a sperm bundle chemoattractant produced by female spheroids were negative. The flagella of the female spheroid were identified as the site of sperm bundle binding. Treatment of female spheroids with trypsin or protease blocked sperm bundle binding, suggesting surface proteins are involved. Sperm bundle binding is not affected by female spheroid age up to 64 h after inversion of the female spheroid. Soybean trypsin inhibitor prevents fertilization pore formation. This suggests that a trypsin‐like enzyme, released by the dissociating sperm bundle, is responsible for fertilization pore formation.
EFFECTS OF MICROTUBULE INHIBITORS ON PRONUCLEAR MIGRATION AND EMBRYOGENESIS IN FUCUS DISTICHUS(PHAEOPHYTA)1
Authors: Brawley Susan H. , Quatrano Ralph S.
Published: December 2004

Pronuclear migration in Fucus distichus spp. edentatus (de la Pyl.) Powell is blocked by incubation of fertilized eggs in colchicine (1 mg/ml) and Nocodazole (2 μg/ ml). Rhizoids form prior to decondensation of the sperm chromatin in eggs in which pronuclear fusion is blocked. This occurs during continuous colchicine incubation as well as in eggs recovering from a short treatment with either drug following fertilization. During recovery of the cells, the sperm and egg chromosomes condense, and the sperm chromosomes migrate toward the egg pronucleus. The delay in migration following removal of colchicine is as much as 24 h and is even slower following removal of Nocodazole. The egg chromosomes form a metaphase plate in treated cells while the sperm chromosomes are still distant in the cytoplasm. This suggests that egg centrioles are important in the mitotic division of the zygote, not sperm centrioles. The effect of colchicine treatment on the mitotic plane and cytokinesis is also discussed.
COENOBIAL CELL NUMBER IN SCENEDESMUS QUADRICAUDA (CHLOROPHYCEAE) AS A FUNCTION OF GROWTH RATE IN NITRATE‐LIMITED CHEMOSTATS1
Authors: Gavis Jerome , Chamberlin Charles , Lystad Lisa D.
Published: December 2004

The relative numbers of cells growing as coenobia of different cell number are functions of growth rate when Scenedesmus quadricauda (Turp.) Bréb. is grown axenically in nitrate‐limited, steady‐state chemostats in continuous light. Unicells decreased from a maximum fraction of 0.04–0.05 of the total number of cells at 0.1 day−1 to 0.01 or less as growth rate increased. The fraction of cells that grew as two‐celled coenobia decreased from about 0.2 to 0.01–0.02. The fraction that grew as 4‐celled coenobia increased from about 0.7–0.8 at 0.1 day−1 to near unity at 0.5–0.6 day−1, and then decreased sharply. The fraction of 8‐celled coenobial cells increased from very small values below 0.6 day−1, to ca. 0.9 at 1.0 day−1.
EFFECT OF CYSTEINE AND METHIONINE ON SULFATE UPTAKE AND PRIMARY PRODUCTIVITY BY AXENIC ALGAL CULTURES AND LAKE MICROPLANKTON COMMUNITIES1
Authors: Monheimer Richard H.
Published: December 2004

The presence of up to 500 μg sulfur·l−1 of an equimolar mixture of cysteine and methionine had virtually no effect on the SO42‐ uptake rate of Navicula pelliculosa, (Bréb.) Hilse whereas the rate of Ankistrodesmus falcatus (Corda) Ralfs was decreased by the presence of 500 μg S· l−1 and Anabaena flos‐aquae (Lyngbye) Bréb. by 50 μg S·l−1. Primary productivity in these axenic cultures was affected (decreased) only in A. falcatus. The C:S uptake ratio was lowest in N. pelliculosa and highest in A. falcatus. Considering these species as representative of groups of naturally occurring algae, patterns of SO42‐ uptake and primary productivity in a eutrophic and a moderately oligotrophic lake reflected the results of the algal culturing experiments: SO42‐ uptake rates, relative to primary productivity, were higher in the presence of diatoms and bluegreen algae and lower when green algae were present; the addition of the cysteine I methionine mixture to the lake waters decreased the rate of microplankton SO42‐ uptake in correlation with the makeup of the algal community; primary productivity decreased upon the addition of cysteine I methionine when green algae were relatively abundant. It is concluded that, in most fresh water systems, the effects of organic sulfur pollution on algal SO42‐ uptake and primary productivity are insignificant as compared to other ecological changes that occur due to that pollution.
OBSERVATIONS ON FILAMENT FORMATION IN MICRASTERIAS FOLIACEA (DESMIDIACEAE, CHLOROPHYTA)1
Authors: Lorch Dietrich W. , Engels Monika
Published: December 2004

Filaments of Micrasterias foliacea Bailey were isolated from a sample of a Texas lake. Cultures were established and examined by light and scanning electron microscopy (SEM). Enzymatic removal of mucilage proved necessary to obtain well preserved cells for SEM investigation. The development of the overlapping polar lobes and the formation of the interlocking apical teeth are described. The importance of these, of mucilage and the primary wall for filament formation is discussed.
MORPHOLOGICAL VARIABILITY OF MITOCHONDRIAL FINE STRUCTURE IN CULTURED GONYAULAX POLYEDRA (PYRRHOPHYTA)1
Authors: Herman Eliot Mark , Sweeney Beatrice M.
Published: December 2004

Mitochondria in Gonyaulax polyedra Stein have a highly variable morphology which depends on their location within the cell. The morphology ranges from mitochondria, 1 μm in cross section, with highly dense cristae which are located within the central sphere of golgi bodies to giant pleomorphic mitochondria, 5–8 μm in cross section containing condensed “chromosome” structures and located in the more peripheral regions of the cell. Elongated mitochondria containing microtubule‐like elements ware also observed.
A Model‐Based Approach to Semi‐Automated Reconstruction of Buildings from Aerial Images
Authors: Khoshelham Kourosh , Li Zhilin
Published: December 2004

Automated reconstruction of building objects from aerial images is a complex problem due to the diversity of buildings as well as noise and low contrast of images, which are the results of distant photography, atmospheric effects and poor illumination. In this paper, a semi‐automated approach to the reconstruction of parametric building models from aerial images is presented, which works with line segments extracted from the image. The model is selected interactively from a library of parametric models. A perceptual grouping technique is used to select the most significant image lines in terms of relations such as proximity and parallelism. Model lines are searched for the same relations as in the grouped image lines, and the corresponding lines undergo a matching procedure, which determines whether or not a match can be found between the given model and image lines. An experiment with aerial images of flat‐roof and gable‐roof buildings is shown and its results indicate the robustness and efficiency of the proposed approach.
Tiny genomes and endoreduplication in Strepsiptera
Authors: Johnston J. S. , Ross L. D. , Beani L. , Hughes D. P. , Kathirithamby J.
Published: December 2004

Using flow cytometry, the genome sizes of two species of Strepsiptera were studied: that of male Caenocholax fenyesi texensis Kathirithamby & Johnston (Myrmecolacidae) at 108 Mb, which is the smallest insect genome documented to date; and those of male and female Xenos vesparum Rossi (Stylopidae), which are 1C = 130 and 133 Mb, respectively. The genome sizes of the following were analysed for comparative purposes: (a) the Hessian fly, Mayetiola destructor (Say), which was previously reported to be the smallest among insects: the male measured at 1C = 121 Mb and the female at 1C = 158 Mb; and (b) the female parasitic, haplodiploid, microhymenopteran wasp, Trichogramma brassicae Bezdenko, which measured at 1C = 246 Mb. The hosts of the strepsipterans were also measured: male Solenopsis invicta Buren, the red imported fire ant (host of male C. f. texensis), which is 1C = 753.3 Mb, and female Polistes dominulus Christ, the paper wasp (host of X. vesparum), is 1C = 301.4 Mb. Endoreduplication (4C) of the genome of the thorax of the male strepsipteran, and higher levels of endoduplication (4, 8, 16C) in the body of the larger female was observed. In contrast, little or no endoreduplication was observed, either in the Hessian fly, or in the parasitic wasp.
Characterization and evolution of furanocoumarin‐inducible cytochrome P450s in the parsnip webworm, Depressaria pastinacella
Authors: Li W. , Zangerl A. R. , Schuler M. A. , Berenbaum M. R.
Published: December 2004

Depressaria pastinacella, the parsnip webworm, a specialist on two genera in the Apiaceae, routinely consumes plant tissues high in furanocoumarin content and is capable of rapid cytochrome P450‐mediated detoxification of these compounds. In this study, four cDNAs were cloned from the larval midgut of this insect: two full‐length CYP6AB3 and CYP6AE1 cDNAs are closely related to members of the furanocoumarin‐metabolizing CYP6B subfamily and two partial CYP9A6 and CYP9A7 cDNAs are related to members of the CYP9A subfamily that have also been linked to the detoxification of xenobiotics. At least one of these P450s (CYP6AB3) is inducible by dietary furanocoumarins, indicating its potential involvement in furanocoumarin metabolism. A homology model of CYP6AB3 was constructed and compared to models of CYP6B1 from the specialist species, Papilio polyxenes, and CYP6B4 from the generalist species, P. glaucus. Structural superpositioning of these models has revealed very high spatial similarity of elements, including the B helix, B′‐C loop, I helix and C‐terminal domain, within the catalytic sites of these proteins. Most importantly, key amino acid residues that can potentially come into contact with furanocoumarin substrates display conservation in their spatial positioning and side chain polarities. Three of these residues, Val103, Leu113 and Phe118 (numbered according to CYP6AB3), are conserved in all three of these proteins, further implicating CYP6AB3 in furanocoumarin metabolism by parsnip webworms. Characterization of these P450 cDNAs will allow for functional analyses aimed at elucidating the molecular mechanisms underlying the coevolutionary interactions between this herbivore and its principal host plant.
Secondary structure, high variability and conserved motifs for domain III of 12S rRNA in the Arthropleona (Hexapoda; Collembola)
Authors: Carapelli A. , Soto‐Adames F. N. , Simon C. , Frati F. , Nardi F. , Dallai R.
Published: December 2004

The robustness of different hypothetical structural models for ribosomal RNAs can be established by comparing sequences from widely different taxonomic groups. Secondary structure models of the two mitochondrial ribosomal subunits have been proposed for a large number of pterygote insects, but little information is available for the more ancient entognath hexapods. We have investigated the most frequently sequenced of the four domains of the mitochondrial small subunit rRNA in twenty‐two collembolan species in the taxon Arthropleona. We provide secondary structure models of this third domain for representative species, and a consensus based on all species studied. This consensus is in partial agreement with previous models. High levels of variation, in terms of length and of primary sequence, are present in the peripheral portions of the domain. Some of the structural elements differ more among genera of springtails than among insect orders. Conversely, a limited number of structural differences compared with other taxa have been detected in the core regions.
Impact of storms on mixed carbonate and siliciclastic shelves: insights from combined diffusive and fluid‐flow transport stratigraphic forward model
Authors: Quiquerez A. , Allemand P. , Dromart G. , Garcia J‐P.
Published: December 2004

A quantitative stratigraphic model of mixed carbonate/siliciclastic continental shelves is presented to investigate the relationships between depositional processes and stratigraphic responses at long‐term, large spatial scales. A diffusion model is combined with a fluid‐flow approach to simulate both long‐term factors, i.e. the processes controlling large‐scale architecture, and short‐term processes, i.e. sediment redistribution by storms. Any net sediment accumulation is the result of the succession of a storm and a fair‐weather period. Sediments are mobilized by waves and advected by low‐frequency currents during storm events. Sediments are then reworked and redistributed downslope by diffusive processes during fair‐weather period. The results are successful in capturing several major characteristics of both modern and ancient depositional systems (geometry, differential preservation, net accumulation rates). The study highlights the importance of waves and unidirectional currents. Depositional geometry and shelf morphology depend on the balance between available sediment supply (generated in situ or detrital) and the transport energy, which is related to the style of sediment transport (diffusive or advective), and to the magnitude and frequency of storms.
Changed bone status in human immunodeficiency virus type 1 (HIV‐1) perinatally infected children is related to low serum free IGF‐I
Authors: Stagi Stefano , Bindi Giuseppe , Galluzzi Fiorella , Galli Luisa , Salti Roberto , De Martino Maurizio
Published: December 2004

introduction  Adults and children affected by human immunodeficiency virus type‐1 (HIV‐1) infection show bone demineralization. Little is known about skeletal status using a quantitative high‐frequency ultrasound (QUS) technique in these patients.

objective  To evaluate the bone quality and assess the role of the IGF system in the bone metabolism and skeletal status of HIV‐1 perinatally infected children.

patients and methods  Serum free and total IGF‐I, IGFBP‐3, serum osteocalcin level, urinary deoxypyridinoline concentration, spontaneous interleukin‐6 (IL‐6) release and broadband ultrasound attenuation (BUA) were evaluated in 44 prepubertal children who had perinatal HIV‐1 infection. The patients were divided into two groups depending on the severity of their clinical condition: group 1 (23 children with no or mild clinical symptoms, mean age 8·0 ± 2·9 years) and group 2 (21 children with severe clinical symptoms, mean age 8·58 ± 2·47 years). Fifty‐five healthy age‐ and sex‐matched controls were analysed for comparison.

results  Compared with group 1 and the controls, group 2 patients showed a significantly reduced BUA Z‐score (P < 0·001), and significantly reduced concentrations of serum osteocalcin (P < 0·001) and urinary deoxypyridinoline (P < 0·001 and P < 0·05, respectively). Group 2 patients also showed significantly reduced serum free IGF‐I (P < 0·001) and total IGF‐I (P < 0·05) levels compared with the controls, but not with group 1. No statistically significant differences were found between the three groups with regard to IGFBP‐3. Group 2 patients showed significantly higher spontaneous IL‐6 release than group 1 patients and controls (P < 0·001). BUA Z‐scores displayed a significant correlation with free IGF‐I in group 2 (r = 0·96; P < 0·001), group 1 (r = 0·56; P = 0·005) and controls (r = 0·50; P < 0·001).

conclusion  Our study shows that only patients affected by perinatal HIV‐1 infection with severe clinical manifestations present significant changes in bone quality and bone metabolism. Our data also show that impairment of skeletal status is related to reduction in serum total and free IGF‐I. Children with perinatal HIV‐1 infection, because of a considerable improvement in life expectancy, seem at great risk of not obtaining an optimal bone mass. A possible therapeutic approach should be considered in these children.
Correlations of adiponectin level with insulin resistance and atherosclerosis in Japanese male populations
Authors: Higashiura Katsuhiro , Ura Nobuyuki , Ohata Jun‐ichi , Togashi Nobuhiko , Takagi Satoru , Saitoh Shigeyuki , Murakami Hideyuki , Takagawa Yoshitoki , Shimamoto Kazuaki
Published: December 2004

objective  Adiponectin, which is secreted specifically by adipose tissue, has been shown to have an anti‐atherosclerotic effect and to improve insulin resistance. The aim of this study was to determine the correlations of plasma adiponectin concentration with insulin resistance and atherosclerosis.

design and methods  We investigated the relationships of adiponectin concentration with insulin sensitivity, high‐sensitivity C‐reactive protein (hCRP) and pulse wave velocity (PWV) in male inhabitants of rural communities in Japan. hCRP and PWV were used as an indexes of atherosclerosis.

results  A negative correlation was found between homeostasis model assessment (HOMA) as an index of insulin resistance and adiponectin concentration. Results of stepwise regression analysis for adiponectin showed that age, HOMA and serum triglyceride (TG) were independently correlated with adiponectin. Multiple regression analysis for lipid profile was also performed and revealed that adiponectin and HOMA were independently correlated with TG and serum high density lipoprotein (HDL)‐cholesterol but not with serum total cholesterol. A significant negative correlation was found between adiponectin and hCRP in all subjects, and a significant negative correlation between adiponectin and PWV was also found in subjects equal or less than 70 years old. When HOMA was added to this analysis, HOMA was found to be independently correlated with hCRP and PWV, but the adiponectin level did not appear to be a significant predictor of hCRP or PWV.

conclusions  The results suggest that adiponectin plays a role in lipid metabolism and correlates with atherosclerosis either directly or through insulin resistance.
Prostasome antigens as targets for sperm agglutinating antibodies demonstrated by 1‐D gel electrophoresis and immunoblottings
Authors: Carlsson L. , Larsson A. , Ronquist G. , Nilsson B. O.
Published: December 2004

Many immunoinfertile men have sperm agglutinating antibodies that are directed against prostasome‐derived antigens, but these antigens have not been defined so far. We selected serum samples with high ELISA titres against prostasomes from a group of immunoinfertile patients with sperm agglutinating antibodies and used the sera for immunoblottings on 1‐D SDS‐PAGE of prostasomes and sperm cells. The immunoblottings with individual antiprostasome antisera on 1‐D SDS‐PAGE of prostasomes, revealed three to 10 bands for each serum. Eighty‐five per cent of the serum samples contained bands in the 70–75 kDa region and 80% of the samples contained bands in the 50–55 kDa region. Immunoblottings of extracted sperm cells, revealed one to six bands in the molecular weight range 25–82 kDa and two of the samples recognized two bands with molecular weights (50 and 43 kDa) similar to immunoblottings of prostasomes. The prostasomal antigens recognized by the high titre‐antisera of immunoinfertile men were generally different from the sperm antigens recognized by the same sera. This suggests that prostasomes offer a new set of antigens available for research on male immunoinfertility and immunocontraception.
Distribution and Acute Stressor‐Induced Activation of Corticotrophin‐Releasing Hormone Neurones in the Central Nervous System of Xenopus laevis
Authors: Yao M. , Westphal N. J. , Denver R. J.
Published: December 2004

In mammals, corticotrophin‐releasing hormone (CRH) and related peptides are known to play essential roles in the regulation of neuroendocrine, autonomic and behavioural responses to physical and emotional stress. In nonmammalian species, CRH‐like peptides are hypothesized to play similar neuroendocrine and neurocrine roles. However, there is relatively little detailed information on the distribution of CRH neurones in the central nervous system (CNS) of nonmammalian vertebrates, and there are currently no comparative data on stress‐induced changes in CRH neuronal physiology. We used a specific, affinity‐purified antibody raised against synthetic Xenopus laevis CRH to map the distribution of CRH in the CNS of juvenile South African clawed frogs. We then analysed stress‐induced changes in CRH immunoreactivity (CRH‐ir) throughout the CNS. We found that CRH‐positive cell bodies and fibres are widely distributed throughout the brain and rostral spinal cord of juvenile X. laevis. Strong CRH‐immunoreactovity (ir) was found in cell bodies and fibres in the anterior preoptic area (POA, an area homologous to the mammalian paraventricular nucleus) and the external zone of the median eminence. Specific CRH‐ir cell bodies and fibres were also identified in the septum, pallium and striatum in the telencephalon; the amygdala, bed nucleus of the stria terminalis and various hypothalamic and thalamic nuclei in the diencephalon; the tectum, torus semicircularis and tegmental nuclei of the mesencephalon; the cerebellum and locus coeruleus in the rhombencephalon; and the ventral horn of the rostral spinal cord. To determine if exposure to an acute physical stressor alters CRH neuronal physiology, we exposed juvenile frogs to shaking/handling and conducted morphometric analysis. Plasma corticosterone was significantly elevated by 30 min after exposure to the stressor and continued to increase up to 6 h. Morphometric analysis of CRH‐ir after 4 h of stress showed a significant increase in CRH‐ir in parvocellular neurones of the anterior preoptic area, the medial amygdala and the bed nucleus of the stria terminalis, but not in other brain regions. The stress‐induced increase in CRH‐ir in the POA was associated with increased Fos‐like immunoreactivity (Fos‐LI), and confocal microscopy showed that CRH‐ir colocalized with Fos‐LI in a subset of Fos‐LI‐positive neurones. Our results support the view that the basic pattern of CNS CRH expression arose early in vertebrate evolution and lend further support to earlier studies suggesting that amphibians may be a transitional species for descending CRH‐ergic pathways. Furthermore, CRH neurones in the frog brain exhibit changes in response to a physical stressor that parallel those seen in mammals, and thus are likely to play an active role in mediating neuroendocrine, behavioural and autonomic stress responses.
Inter‐Relationships Between the Secretory Dynamics of Thyrotrophin‐Releasing Hormone, Thyrotrophin and Prolactin in Periovulatory Mares: Effect of Hypothyroidism
Authors: Alexander S. L. , Irvine C. H. G. , Evans M. J.
Published: December 2004

We used our nonsurgical technique for collecting pituitary venous blood to relate the dynamics of thyrotrophin‐releasing hormone (TRH) secretion to the secretion patterns of both prolactin and thyrotrophin in periovulatory mares, either euthyroid (n = 5) or made hypothyroid by treatment with propyl‐thiouracil (n = 5). Pituitary venous blood was collected continuously and divided into 1‐min aliquots for 4 h. To test the effect of dopamine on the relationship between secretion patterns, sulpiride, a selective D2 receptor antagonist, was given i.m. after 2 h of sampling. Thorough testing of the model and blood collection procedure revealed no sites of TRH loss. Hypothyroidism increased the mean secretion rates of TRH (P = 0.04) and thyrotrophin (P < 0.0001) but not prolactin. Sulpiride increased prolactin secretion rates in hypothyroid (P < 0.0001) and control (P = 0.007) mares, but did not alter TRH or thyrotrophin secretion rates. In both groups of mares, all three hormones were secreted episodically but not rhythmically. In both groups, the secretion pattern of TRH was almost always significantly related to that of thyrotrophin, as assessed by cross correlation and cross approximate entropy (ApEn) analysis. However, the degree of linear correlation was weak, with only 14% (hypothyroid) or 8% (controls) of the variation in thyrotrophin secretion rates attributable to TRH. Prolactin and TRH secretion patterns before sulpiride were coupled on cross ApEn analysis in both groups, and the minute‐to‐minute secretion rates of the two hormones were correlated in four hypothyroid and three euthyroid mares. Overall, the small, but significant, degree of association between TRH and prolactin was similar to that between TRH and thyrotrophin. In hypothyroid mares, sulpiride increased (P = 0.02) the synchrony between TRH and prolactin patterns. We conclude that in horses: (i) little TRH degradation occurs during passage through the pituitary or in blood after 1 h at 37 °C; (ii) TRH is not the major factor controlling minute‐to‐minute fluctuations in either thyrotrophin or prolactin; and (iii) reducing two strongly inhibitory inputs (i.e. dopamine and thyroid hormones) may magnify the stimulatory effect of TRH on prolactin secretion.
Concurrent interactions of heme and FLU with Glu tRNA reductase (HEMA1), the target of metabolic feedback inhibition of tetrapyrrole biosynthesis, in dark‐ and light‐grown Arabidopsis plants
Authors: Goslings David , Meskauskiene Rasa , Kim Chanhong , Lee Keun Pyo , Nater Mena , Apel Klaus
Published: December 2004

The regulation of tetrapyrrole biosynthesis in higher plants has been attributed to metabolic feedback inhibition of Glu tRNA reductase by heme. Recently, another negative regulator of tetrapyrrole biosynthesis has been discovered, the FLU protein. During an extensive second site screen of mutagenized flu seedlings a suppressor of flu, ulf3, was identified that is allelic to hy1 and encodes a heme oxygenase. Increased levels of heme in the hy1 mutant have been implicated with inhibiting Glu tRNA reductase and suppressing the synthesis of δ‐aminolevulinic acid (ALA) and Pchlide accumulation. When combined with hy1 or ulf3 upregulation of ALA synthesis and overaccumulation of protochlorophyllide in the flu mutants were severely suppressed supporting the notion that heme antagonizes the effect of the flu mutation by inhibiting Glu tRNA reductase independently of FLU. The coiled‐coil domain at the C‐terminal end of Glu tRNA reductase interacts with FLU, whereas the N‐terminal site of Glu tRNA reductase that is necessary for the inhibition of the enzyme by heme is not required for this interaction. The interaction with FLU is specific for the Glu tRNA reductase encoded by HEMA1 that is expressed in photosynthetically active tissues. FLU seems to be part of a second regulatory circuit that controls chlorophyll biosynthesis by interacting directly with Glu tRNA reductase not only in etiolated seedlings but also in light‐adapted green plants.
The tomato carotenoid cleavage dioxygenase 1 genes contribute to the formation of the flavor volatiles β‐ionone, pseudoionone, and geranylacetone
Authors: Simkin Andrew J. , Schwartz Steven H. , Auldridge Michele , Taylor Mark G. , Klee Harry J.
Published: December 2004

Volatile terpenoid compounds, potentially derived from carotenoids, are important components of flavor and aroma in many fruits, vegetables and ornamentals. Despite their importance, little is known about the enzymes that generate these volatiles. The tomato genome contains two closely related genes potentially encoding carotenoid cleavage dioxygenases, LeCCD1A and LeCCD1B. A quantitative reverse transcriptase‐polymerase chain reaction analysis revealed that one of these two genes, LeCCD1B, is highly expressed in ripening fruit (4 days post‐breaker), where it constitutes 0.11% of total RNA. Unlike the related neoxanthin cleavage dioxygenases, import assays using pea chloroplasts showed that the LeCCD1 proteins are not plastid‐localized. The biochemical functions of the LeCCD1 proteins were determined by bacterial expression and in vitro assays, where it was shown that they symmetrically cleave multiple carotenoid substrates at the 9,10 (9′,10′) positions to produce a C14 dialdehyde and two C13 cyclohexones that vary depending on the substrate. The potential roles of the LeCCD1 genes in vivo were assessed in transgenic tomato plants constitutively expressing the LeCCD1B gene in reverse orientation. This over‐expression of the antisense transcript led to 87–93% reductions in mRNA levels of both LeCCD1A and LeCCD1B in the leaves and fruits of selected lines. Transgenic plants exhibited no obvious morphological alterations. High‐performance liquid chromatography analysis showed no significant modification in the carotenoid content of fruit tissue. However, volatile analysis showed a ≥50% decrease in β‐ionone (a β‐carotene‐derived C13 cyclohexone) and a ≥60% decrease in geranylacetone (a C13 acyclic product likely derived from a lycopene precursor) in selected lines, implicating the LeCCD1 genes in the formation of these important flavor volatiles in vivo.
The ubiquitin ligase XBAT32 regulates lateral root development in Arabidopsis
Authors: Nodzon Lisa A. , Xu Wei‐Hui , Wang Yongsheng , Pi Li‐Ya , Chakrabarty Pranjib K. , Song Wen‐Yuan
Published: December 2004

Ubiquitin‐mediated protein modification plays a key role in many cellular signal transduction pathways. The Arabidopsis gene XBAT32 encodes a protein containing an ankyrin repeat domain at the N‐terminal half and a RING finger motif. The XBAT32 protein is capable of ubiquitinating itself. Mutation in XBAT32 causes a number of phenotypes including severe defects in lateral root production and in the expression of the cell division marker CYCB1;1::GUS. The XBAT32 gene is expressed abundantly in the vascular system of the primary root, but not in newly formed lateral root primordia. Treatment with auxin increases the expression of XBAT32 in the primary root and partially rescues the lateral root defect in xbat32‐1 mutant plants. Thus, XBAT32 is a novel ubiquitin ligase required for lateral root initiation.
Overexpression of tomato LeAGP‐1 arabinogalactan‐protein promotes lateral branching and hampers reproductive development
Authors: Sun Wenxian , Kieliszewski Marcia J. , Showalter Allan M.
Published: December 2004

LeAGP‐1 is a glycosylphosphatidylinositol (GPI)‐anchored arabinogalactan‐protein (AGP) in tomato (Lycopersicon esculentum). Patterns of mRNA expression and protein localization for LeAGP‐1 indicate that it likely functions in certain aspects of plant growth and development. To elucidate LeAGP‐1 function(s), transgenic tomato plants expressing enhanced green fluorescent protein (GFP) fused to LeAGP‐1 [GFP‐LeAGP‐1] or two LeAGP‐1 variants, one lacking the C‐terminal GPI‐anchor domain [GFP‐LeAGP‐1ΔC] and the other lacking the lysine‐rich domain [GFP‐LeAGP‐1ΔK], under the control of the CaMV35S promoter were produced using Agrobacterium‐mediated transformation. Transgenic T0 and T1 lines with high levels of both GFP‐LeAGP‐1 mRNA and protein: (i) were significantly shorter; (ii) were highly branched; (iii) produced more flower buds, but most of these flowers did not mature, resulting in less fruit production; and (iv) produced seeds that were significantly smaller than normal seeds. Overexpression of LeAGP‐1ΔK had a similar or even more pronounced effect on plant vegetative and reproductive growth, while the effect of LeAGP‐1ΔC overexpression on plant reproduction was minimal. These results indicate that the GPI anchor is critical for LeAGP‐1 function. As the phenotype of GFP‐LeAGP‐1 overexpressing transgenic plants is similar to that of cytokinin‐overproducing plants, mRNA expression patterns of LeAGP‐1 under different hormone treatments were examined. Cytokinins upregulated LeAGP‐1 mRNA expression, while auxins and ABA inhibited LeAGP‐1 mRNA expression. Based on these results, GPI‐anchored LeAGP‐1 most likely functions in plant growth and development in concert with auxin/cytokinin signaling.
AtMYB32 is required for normal pollen development in Arabidopsis thaliana
Authors: Preston Jeremy , Wheeler Janet , Heazlewood Joshua , Li Song Feng , Parish Roger W.
Published: December 2004

AtMYB32 gene is a member of the R2R3 MYB gene family coding for transcription factors in Arabidopsis thaliana. Its expression pattern was analysed using Northern blotting, in situ hybridization and promoter‐GUS fusions. AtMYB32 is expressed in many tissues, but most strongly in the anther tapetum, stigma papillae and lateral root primordia. AtMYB32‐GUS was induced in leaves and stems following wounding, and in root primordia by auxin. T‐DNA insertion populations were screened and two insertion mutants were identified, both of which were partially male sterile, more than 50% of the pollen grains being distorted in shape and lacking cytoplasm. AtMYB4 is closely related to AtMYB32 and represses the CINNAMATE 4‐HYDROXYLASE gene. Distorted pollen grains were produced in both AtMYB4 insertion mutant and overexpression lines. In an AtMYB32 insertion mutant, the transcript levels of the DIHYDROFLAVONOL 4‐REDUCTASE and ANTHOCYANIDIN SYNTHASE genes decreased while the level of the CAFFEIC ACID 0‐METHYLTRANSFERASE transcript increased. Change in the levels of AtMYB32 and AtMYB4 expression may influence pollen development by changing the flux along the phenylpropanoid pathways, affecting the composition of the pollen wall.
Amplification of proopiomelanocortin mRNA in canine skin: preliminary results
Authors: KIDNEY CAROLYN M. , MACDONALD JOHN M. , ANGARANO DONNA W. , INSALACO THOMAS A. , KEMPAINNEN ROBERT J. , SARTIN JAMES L.
Published: December 2004

Abstract Skin and pituitary specimens were obtained from a normal chow‐chow cross‐bred dog. Total messenger RNA (mRNA) was extracted, reversed transcribed and the proopiomelanocortin (POMC) mRNA was amplified by polymerase chain reaction using canine specific primers. The expected 391 bp amplification product was detected in both canine skin and pituitary samples. Sequencing of this product showed 100% homology to the GenBank sequence for canine PMOC cDNA, and confirmed its remarkable homology to sequences of human, pigtailed macaque, mink, pig, mouse, rat and cow POMC. These preliminary results suggest that transcription of POMC mRNA occurs in canine skin. The nature of resident or nonresident cells transcribing the POMC gene in canine skin remains unknown at this time.
Evaluation of adrenal function in small‐breed dogs receiving otic glucocorticoids
Authors: GHUBASH R. , MARSELLA R. , KUNKLE G.
Published: December 2004

Abstract The objectives of this study were to evaluate adrenal function after otic glucocorticoid [Tresaderm® (dexamethasone) and Otomax® (betamethasone)] therapy in small‐breed dogs without evidence of otitis and to evaluate the length of time needed for resolution of adrenal suppression after discontinuation of treatment. Fourteen clinically healthy, privately owned, small‐breed dogs with normal ears and normal adrenocorticotropin (ACTH) stimulation tests were assigned to one of two treatment groups, receiving one of the medications at the manufacturer's recommended dosage twice daily for 2 weeks. All of the dogs in the betamethasone treatment group had normal ACTH stimulation tests after 2 weeks of treatment. In contrast, 5/7 (71.43%) in the dexamethasone group, had suppressed adrenocortical responses to exogenous ACTH. Three of these five dogs (42%) returned to normal values 1 week after ceasing the medication and two (28.57%) returned to normal values 2 weeks after ceasing the medication. In conclusion, it appears that adrenal function can be suppressed for up to 2 weeks in dogs receiving otic dexamethasone. A follow‐up study repeating this work in dogs with inflamed ears is needed before further clinical recommendations can be made.
Quantification of Blo t 5 in mite and dust extracts by two‐site ELISA
Authors: Yi F. C. , Lee B. W. , Cheong N. , Chua K. Y.
Published: December 2004

Background:  Blomia tropicalis is an important mite species in the tropical and sub‐tropical regions of the world. Blo t 5 is the major allergen with up to 70% sensitization rates in B. tropicalis allergic populations.

Methods:  Mice were immunized intramuscularly with naked plasmid DNA encoding Blo t 5 gene with in vivo electroporation. Blo t 5 monoclonal antibodies were generated using methylcellulose‐based hybridoma kit. Monoclonal antibody (mAb) 4A7 was characterized by two‐dimensional electrophoresis immunoblotting. A specific quantitative two‐site enzyme‐linked immunosorbent assay (ELISA) was developed with mAb 4A7 and guinea pigs Blo t 5 polyclonal antibody as capture and detection antibodies, respectively. This system was tested with Blo t 5 in crude extracts and dust samples.

Results:  A high‐affinity mAb 4A7 recognizing several isoforms of Blo t 5 has been generated. Monoclonal antibody 4A7 is useful for immunoblotting and two‐site ELISA. The two‐site ELISA developed has a high sensitivity, with a detection limit of 10 pg/ml. The assay is species‐specific and recognized the same epitopes on both native and recombinant Blo t 5. The assay developed is able to detect Blo t 5 in commercial diagnostic and therapeutic B. tropicalis extract. Blo t 5 quantification in dust samples showed that Blo t 5 is present in a high quantity in Singapore dust.

Conclusions:  A highly sensitive and specific two‐site ELISA has been developed. The assay system developed is useful for the quantification of Blo t 5 in mite and environmental dust extracts.
Organization of secondary lymphoid tissue and local IgE formation to Staphylococcus aureus enterotoxins in nasal polyp tissue
Authors: Gevaert P. , Holtappels G. , Johansson S. G. O. , Cuvelier C. , van Cauwenberge P. , Bachert C.
Published: December 2004

Background:  Bilateral nasal polyposis (NP) is characterized by high concentrations of IgE in NP tissue, which show no relation to the atopic status. We aimed to study the relationship between systemic and local IgE formation, nasal carriage of Staphylococcus aureus and nasal polyposis.

Methods:  In serum and nasal tissue homogenates from 24 NP patients and 12 controls, we determined concentrations of total IgE and IgE antibodies to inhalant allergens and S. aureus enterotoxins (SAEs; A,B,C,D,E,TSST) by ImmunoCAP. Tissue cryosections were stained for CD3, CD20, CD38, CD23, FcεRI, IgE and SEA/SEB.

Results:  We demonstrated a higher incidence of S. aureus colonization (17/24) and IgE antibodies to SAEs in NP tissue (12/24) compared with controls (3/12 and 0/12, respectively). Total IgE and IgE antibodies in serum and NP tissue were dissociated because of local polyclonal IgE formation in NP tissue. Staining of NP tissue revealed follicular structures characterized by B and T cells, and lymphoid accumulations with diffuse plasma cell infiltration.

Conclusions:  We demonstrated the organization of secondary lymphoid tissue in polyp tissue and a polyclonal hyper‐immunoglobulinemia E associated with the presence of IgE antibodies to SAEs, colonization with S. aureus, and tissue eosinophilia in a relevant subgroup of polyp patients.
Bone disease in primary biliary cirrhosis: Lack of association with distal renal tubular acidosis
Authors: FARIAS ALBERTO Q , GONÇALVES LUCIANA L , CANÇADO EDUARDO LR , SEGURO ANTONIO C , CAMPOS SILVIA B , ABRANTES‐LEMOS CLARICE P , CARRILHO FLAIR J
Published: December 2004

Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.

Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test‐induced systemic metabolic acidosis.

Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.

Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.
Physiological and morphological variation of Gremmeniella abietina from Spain
Authors: Santamaría O. , Pajares J. A. , Diez J. J.
Published: December 2004

Gremmeniella abietina isolated from Pinus halepensis in Spain was characterized based on disease symptoms and conidia morphology. The disease symptoms, which became more evident in the spring, included drying up of needles and branches with some distortion of terminal twigs, resulting in dieback and sometimes to death of trees of all sizes. Variation in conidia size and growth rate was investigated between 15 isolates from Spain, and the conidia morphology was compared with four isolates from Finland, four from Switzerland and three from the US. Great variation occurred between Spanish isolates both in growth rates and in conidia size. The growth rates of the isolates were greatest on malt agar amended with pine needle extract and at 15°C. The length and the width of the conidia of the isolates from Spain ranged between 10.7–44.8 and 1.5–4.4 μm, and most of them had three septa. The results suggest that the isolates from Spain do not belong to the Alpine biotype, and the disease symptoms caused by these isolates resembled those of the European biotype.
Field evaluation of the efficacy of a probiotic containing Bacillus licheniformis and Bacillus subtilis spores, on the health status and performance of sows and their litters
Authors: Alexopoulos C. , Georgoulakis I. E. , Tzivara A. , Kritas S. K. , Siochu A. , Kyriakis S. C.
Published: December 2004

The aim of this study was to assess the efficacy of BioPlus 2B, a probiotic containing Bacillus licheniformis and Bacillus subtilis spores, on the health status and productivity of sows and their litters. A total of 109 gilts and sows were allocated into two experimental groups, as follows: untreated controls (UC) and BioPlus 2B (same feeding as the UC group plus BioPlus 2B) at a dose of 400 g/ton of feed (equal to 1.28 × 106 viable spores/g of feed). Treatment started from the day of allocation (14 days prior to the expected farrowing) up to the weaning day. Homogeneity of the groups was satisfied with regard to the parity. From the results it was evident that BioPlus 2B supplementation of the feed improved gilt/sow performance as shown by: (i) the increase of sow feed consumption during the first 14 days postpartum and (ii) the decrease of sow weight loss during the suckling period. Certain blood and milk parameters were significantly improved, as shown by higher serum cholesterol and total lipids concentrations and higher milk fat and protein content at mid‐suckling period. As a consequence, a positive effect was also noticed as regard litter health and performance characteristics in terms of: (i) decrease in piglet diarrhoea score, (ii) decrease in pre‐weaning mortality thus leading to increase in the number of weaned piglets per litter and (iii) increase in piglet body weight at weaning. Moreover, BioPlus 2B tended to improve the health status and fertility of sows demonstrating: (i) tendency to a lower proportion of sows with Mastitis‐Metritus‐Agalactia (MMA) problems and (ii) lower proportion of sows returning to oestrus.
An Osteoid Variant of Cutaneous Melanoma in a Dog Detected by S100 and Melan A Markers
Authors: Maliver P. , Estrada M. , Lagadic M. , Mialot M. , Manin S. , Fontaine J.‐J.
Published: December 2004

Osteoid malignant melanoma is a rare type of melanoma described in humans and dogs with some areas of bone differentiation. In this tumour, the origin of the bone matrix remains unclear. We report one case of this variant with, for the first time, a cutaneous origin in a dog. Malignant melanomas are aggressive tumours. Amelanotic tumours are sometimes difficult to recognize as they require immunohistochemical evaluation for an adequate diagnosis and we have used anti‐vimentin, S100, and melan A antibodies for identification. Melan A is less sensitive but more specific than S100 in identifying amelanotic melanomas. This tumour was positive for vimentin, S100 and melan A, including the areas of osteoid. These results suggest osteoid differentiation of tumour cells rather than induced stromal metaplasia.
Microbiological Features of Staphylococcus schleiferi subsp. coagulans, Isolated from Dogs and Possible Misidentification with Other Canine Coagulase‐positive Staphylococci
Authors: Zdovc I. , Ocepek M. , Pirš T. , Krt B. , Pinter L.
Published: December 2004

Staphylococcus schleiferi subsp. coagulans has only rarely been isolated and identified from the external auditory meatus of dogs suffering from external otitis. Its morphological and basic biochemical characteristics are of relatively little value for identification, as it phenotypically resembles another coagulase‐positive staphylococci (CPS) and, consequently, may be easily misidentified as S. intermedius or even as S. aureus. In the present work, differentiation of S. schleiferi ssp. coagulans was therefore based on specific biochemical and genetic methods. All the strains were evaluated with the following commercial methods: Api Staph System (bioMérieux, Marcy l'Etoil, France), BBL Crystal Identification Systems (Gram‐Positive ID Kit and Rapid Gram‐Positive ID Kit; Becton Dickinson), and GEN‐PROBE® AccuProbe, Staphylococcus aureus identification test (bioMérieux). Gram‐Positive ID System/GP database includes the broadest range of staphylococcal species and correctly identifies the majority of strains important in veterinary medicine. Therefore, it is an acceptable alternative to conventional methods for identification of canine staphylococcal isolates. Reliable differentiation of S. aureus from S. schleiferi ssp. coagulans and S. intermedius was feasible with AccuProbe for S. aureus, which gave positive results only for S. aureus; all other CPS tested were negative.