bluuebunny/crossref_metadata_2025_split huggingface dataset:
External ultrastructure and function of the “spiculum copulatus” (SC) of the German cockroach, Blattella germanica (L.) (Dictyoptera:Blattellidae)
Authors: Ramaswamy S. B. , Gupta A. P. , Fowler H. G. 
Published: June 2005

AbstractStudies were undertaken to determine the ultrastructure and function of the spiculum copulatus (SC) on the seventh abdominal tergum of adult male Blattella germanica (L.).The SC is located on the seventh abdominal tergum in between the anterior pair of tergal gland orifices. It is approximately 250 μm long and 40 μm in diameter at the base. It is invested with numerous sensilla, many of which are bifurcate and trifurcate. Cauterization of the SC leads to cessation of certain phases of the male precopulatory behavior (such as extension and arching of the abdomen and clamping of the genitalia), thereby preventing mating. The cauterization studies indicate that the SC and its sensilla possibly serve a mechanoreceptive function.
An experimental analysis of the role of bottle cells and the deep marginal zone in gastrulation of Xenopus laevis
Authors: Keller R. E. 
Published: June 2005

AbstractEarlier work suggested that the change in shape or the active migration of the bottle cells in the amphibian blastoporal region results in an invagination that comprises a major part of gastrulation. In the present study of gastrulation in Xenopus laevis, microsurgical extirpation and rearrangement experiments, analyzed with time‐lapse cinemicrography and scanning electron microscopy, show that the bottle cells have a lesser role in gastrulation. Gastrulation is not a process of invagination but of involution of the deep and superficial layers of the marginal zone. Involution is dependent on unique properties of the cells in the deep marginal zone. In contrast, the superficial layer, including the bottle cells, does not have properties essential for involution but is passively moved inside to form the lining of the archenteron by what is probably an active migration of the underlying cells of the deep marginal zone. Bottle cells form by the shrinking and thickening of the superficial layer in the late blastula and early gastrula. They are moved inside, largely because of their attachment to the underlying deep cells, and then they spread and flatten in the latter half of gastrulation to form a large area of the lining of the periphery of the archenteron. The formation of the initial blastoporal groove by bending of the superficial cell sheet during bottle cell formation and the extension of the periphery of the archenteron during spreading of the bottle cells is the extent of the active contribution of bottle cells to the depth of the archenteron. The bulk of the depth is generated by the vegetal extension of the marginal zone and the movement of the involuted deep cells toward the animal pole.
Characterization of the female sterile (1) 1304 mutant of Drosophila melanogaster: Pattern of RNA metabolism in the ovary
Authors: Mulligan Pamela Khipple 
Published: June 2005

AbstractThe female sterile mutant of Drosophila melanogaster, fs(1)1304 (1‐19 ± 2), has been characterized. Our studies show that the mutation affects the organization of nucleolar material in the ovarian nurse cells and the pattern of RNA metabolism in the ovary. Autoradiographic analysis of incorporation of 3JH‐uridine in vivo and analysis of 3H‐uridine incorporation into high molecular weight RNA in vitro suggest that RNA from the ovaries of homozygous fs flies is degraded at a higher rate than that from heterozygous fs and wild‐type ovaries. It is likely that the RNA class affected is ribosomal RNA. These data are discussed in the context of the functional role for the wild‐type gene allelic to fs(1)1304, and it is suggested that one of the effects of the mutation may be on the biogenesis of ribosomes that are to be stored in the oocyte.
Concerning the primary defect leading to the pleiotropic effects caused by anophthalmic white (Wh) in the Syrian hamster Mesocricetus auratus
Authors: Asher James H. 
Published: June 2005

AbstractTen physiological parameters, controlled by the pituitary‐hypo‐thalamic axis, were measured upon males of three genotypes: whwh (cream), Whwh (black eyed white) and WhWh (Anophthalmic white). Univariate analyses of variance comparing data from these hamsters indicated that the gene significantly affects six of these physiological parameters. A principal component and correlation analysis using the multivariate data indicated that of these 10 parameters, six were linearly independent and five were significantly altered by the action of the gene Wh.The results of these analyses and those previously reported suggest that the gene Wh alters the development of the embryonic diencephalon which, in turn, alters the development of the eye and pituitary leading to significant affects on the physiological parameters measured. A new method is described which should, in general, permit the determination of the primary action of a gene in the case of highly pleiotropic mutants.
Asexual reproduction and regeneration properties of a nonbudding mutant of Hydra viridis
Authors: Novak Patricia L. , Lenhoff Howard M. 
Published: June 2005

AbstractA nonbudding mutant of Hydra viridis reproduced asexually in an atypical but unique manner in terms of morphogenesis and rate of hydranth formation. It sprouted tentacles randomly along the body column at a distinct distance from the head end of the animal. These tentacles then clustered and a hypostome formed at the center of the cluster. Asexual reproduction by the mutant was disorganized and slow. A single mutant was able to produce an average of only 10 hydranths in two months as compared to the wild type which can produce as many as 1010 hydra during that same period. Both the apical and basal portions of a bisected nonbudding mutant regenerated atypically. Unlike wild type hydra, the cut apical portion formed a second head at the regenerating end if the transection was made at least 2 mm away from the original head. The basal portion of a transected mutant regenerated a head and formed supernumerary tentacles along its body column. Bipolar mutants with both heads decapitated sprouted supernumerary tentacles along their midbody column. Tentacle sprouting in these bipolar mutants did not develop within 1.7 ± 0.4 mm of the newly regenerated heads. This distance is similar to that (1.9 ± 0.1 mm) existing between the head and the budding region in wild type hydra. The number of supernumerary tentacles sprouted was proportional to the original length of the bipolar mutant.
Fluorescent observations on the stress fiber system of neural crest cells after con a treatment. A simple, quick, fluorescent method
Authors: Moran Denis 
Published: June 2005

AbstractConcanavalin A (Con A), 25 μg/ml in the tetrameric form, inhibits migration and differentiation of cultured amphibian neural crest. Affected cells loose their angulated morphology and become rounded. A correlation exists between the lectin treatment and the overall cellular and stress fiber morphology. We describe a quick, simple method for disclosing the stress fiber system using fluorescence microscopy after staining with 1% alcoholic eosin.
Cytokinesis: Cleavage furrow establishment in cylindrical sand dollar eggs
Authors: Rappaport R. 
Published: June 2005

AbstractBy confining fertilized, denuded sand dollar (Echinarachnius parma) eggs in short lengths of capillary tubing so that they were reshaped into elongate cylinders it was possible to control the orientation of both the mitotic apparatus and the subsequent cleavage furrow as well as the distance from the mitotic apparatus to the cylindrical cell surface. The technique left the polar regions accessible to experimentation and was used before first and second cleavages.The time when the equatorial surface becomes capable of forming a complete, permanent furrow which can function independently of the mitotic apparatus was determined by aspirating the mitotic apparatus from one of a pair of cylindrical cells at second cleavage and timing the interval between the operation and the appearance of the furrow in the control cell. When the mitotic apparatus is removed 4 minutes or less before control furrowing, the operated cell cleaves, but when the same operation is accomplished 5 minutes or more before control division, furrows do not appear in the operated cell. The results imply that the necessary interaction between the mitotic apparatus and the surface is not completed until 4 minutes before the furrow initiates function, and that thereafter the mitotic apparatus is dispensable. The distance between astral centers and the extent of their radiate structure continue growing after the position of the furrow is established.Experiments performed before the mitotic apparatus becomes dispensable, during the period of its interaction with the surface, revealed that agitation of the poles by vibration and repeated manipulation did not interfere with division when imposed continuously until the furrow appeared. Changing the shape of the poles did not affect cleavage; neither did aspiration of polar cytoplasm and polar portions of asters before both first and second cleavage. Cleavage also occurred despite sequestration of the polar portions of both asters in large‐bore pipettes. Repeated skewering of the mitotic apparatus along the length of its midline often altered its appearance but did not prevent division.
The roles of Ca and Mg in starfish oocyte maturation induced by 1‐methyladenine
Authors: Rosenberg Michael P. , Lee Harold H. 
Published: June 2005

AbstractThe ovarian hormone 1‐methyladenine (1‐MA) stimulates fully grown starfish oocytes to undergo germinal vesicle breakdown (GVB). Patiria miniata oocytes treated with 10−6 M 1‐MA underwent GVB by 45 minutes of treatment. However, in the absence of extracellular Ca++ GVB was delayed, with maximum GVB occuring at 180 minutes of treatment. Both the rate and amount of3 H‐1‐MA bound were depressed in the absence of extracellular Ca++ Reflecting this decrease in hormone binding, the minimum time oocytes in CaFSW needed to be exposed to the hormone was increased from 12 to 35 minutes. Direct measurement of total cellular Ca concentrations during 1‐MA‐induced maturation revealed an increase in Ca levels by 30 minutes posttreatment, followed by a decrease to initial level by 60 minutes. In the absence of extracellular Mg++, oocytes treated with 1‐MA did not undergo GVB. However, binding of the hormone was not dependent on extracellular Mg++. Total cellular Mg concentrations were found to increase to maximum levels by 10 minutes of hormone treatment, and to decrease to basal levels after 30 minutes. Our data suggest that free‐diffusable Mg++ was necessary for hormone action during the critical hormone‐dependent period, while extracellular Ca++ was important for hormone binding. Furthermore, we interpret our data to indicate that 1‐MA regulates oocyte permeability to Ca and Mg during oocyte maturation.
Direct detection of two cross‐reactive antigens between porcine and rabbit zonae pellucidae by radioimmunoassay and immunoelectrophoresis
Authors: Wood David M. , Dunbar Bonnie S. 
Published: June 2005

AbstractZonae pellucidae were isolated from oocytes obtained from rabbit and porcine ovaries. Antisera were prepared in rabbits against heat‐solubilized porcine zonae and in guinea pigs against intact and heat‐solubilized rabbit zonae and against purified rabbit zona proteins isolated from two‐dimensional electro‐phoresis gels. These antisera were used in radioimmunoassay studies to show cross‐reactivity between porcine and rabbit zona antigens. Immunoelectrophoresis studies also demonstrated the immunochemical cross‐reactivity between two distinct antigens of rabbit and porcine zonae. These two rabbit zona antigens were demonstrated to be immunochemically identical to porcine zona antigens by crossed‐line immunoelectrophoresis.
Specificity of H‐2 antigens expressed on mouse blastocysts
Authors: Cozad Karen M. , Warner Carol M. 
Published: June 2005

AbstractA highly sensitive cytotoxicity assay was used to detect H‐2 antigens on mouse blastocyst stage embryos of the b, a, k, and d haplotypes. The assay was based on the principle that live embryos incorporate 3H‐thymidine into DNA whereas embryos killed with antiserum and complement do not. The use of specific alloantisera showed that blastocysts of different haplotypes express different H‐2 antigens. Thus, positive evidence was obtained for the expression of Kd and Dk molecules and negative evidence for the expression of Db, Kk, and Dd molecules. Evidence was also obtained that blatocysts express different H‐2 antigens than those found on adult lymphocytes. Unexpected cross‐reactions were found when some of the alloantisera were tested on blastocysts of different haplotypes. It is proposed that the aberrant expression of H‐2 antigens on embryos might facilitate their escape from surveillance by the maternal immune system.
Studies on the female sterile mutant Rudimentary of Drosophila melanogaster. IV. The activities of de novo and salvage pathway enzymes for pyrimidine biosynthesis during oogenesis, embryonic and postembryonic development of wild‐type flies
Authors: Fausto‐Sterling Anne 
Published: June 2005

AbstractIn order to gain a better understanding of how a defect in pyrimidine biosynthesis leads to the specific set of morphological aberrations seen in Drosophila bearing the mutant allele of rudimentary, we made the following measurements of enzyme activity in wild type flies: (1) during ovarian development – the first three enzymes of the de novo pathway for pyrimidine biosynthesis (aspartate transcarbamylase, dihydroorotase, and carbamyl phosphate synthetase) and two enzymes in the salvage pathway for pyrimidine biosynthesis – uridine kinase and uridine phosphorylase; (2) during embryonic development – uridine kinase and uridine phosphorylase in embryos taken at hourly intervals; and (3) during postembryonic development – uridine kinase and uridine phosphorylase.Our results suggest: (1) that the de novo pyrimidine enzymes are synthesized during the early stages of oogenesis, while the pattern for the salvage pathway enzymes is somewhat different; (2) that a lowering of uridine kinase activity at 13 hours of embryonic development may be responsible for bringing on the developmental crisis in r embryos; and (3) that the postembryonic pattern of activity for salvage pathway enzymes, with one exception, is quite similar to that for the de novo pathway enzymes.
Induction of malformed zooids and determination of polarity in palleal buds of the polystyelid ascidian, Polyandrocarpa misakiensis
Authors: Oda Takaharu , Watanabe Hiroshi 
Published: June 2005

AbstractThe development of malformations was studied in palleal buds of the polystyelid ascidian, Polyandrocarpa misakiensis. Various malformations were induced by transection of protruding buds. Three types could be distinguished: zooids with reversed bilateral asymmetry, zooids with double malformations, and zooids with three apertures. During the early developmental stages of transected proximal pieces, when depigmentation occurred in the distal area, the pieces produced zooids with reversed bilateral asymmetry. When depigmentation occurred in the distal and proximal areas, the pieces induced either zooids with double malformations or zooids with three apertures. In the former, the two depigmented areas were about the same size, whereas in the latter the two areas were very different in size. The individuals occurring from the depigmented proximal area had the same polarity as the parent. Individuals derived from the depigmented distal area displayed either reversal of the left‐right (L‐R) axis (reversed laterality) or reversal of the L‐R and anteroposterior (A‐P) axes (normal laterality). The malformed zooid with reversed L‐R axis produced buds with reversed laterality. We examined the frequency of induction of these malformed zooids in relation to the following four points: 1) the position of the parent body at which buds are produced, 2) the different developmental stages of blastogenesis, 3) the different levels along the maximum protruding bud, and 4) the different transecting times of the maximum protruding bud. The results are discussed in relation to the mechanism of the expression of polarity in the normal development of the palleal bud.
Fertile life of acrosome‐reacted guinea pig spermatozoa
Authors: Fleming Alan D. , Yanagimachi Ryuzo 
Published: June 2005

AbstractTo study the fertile life of acrosome‐reacted guinea pig spermatozoa, spermatozoa were induced to undergo a synchronous acrosome reaction after which vigorously motile acrosome‐reacted spermatozoa were isolated from acrosome‐intact ones. Acrosome‐reacted spermatozoa thus prepared were incubated in vitro for various periods of time before they were mixed with zona‐intact and zona‐free eggs. Such spermatozoa retained their ability to fertilize zona‐intact eggs for at least 2 hours after the acrosome reaction; thereafter they rapidly lost this ability. There was a close correlation between the decline and loss of the ability to penetrate the zona and the loss of hyperactivated motility by spermatozoa, indicating the importance of vigorous motility in passing through the zona. The ability of acrosome‐reacted spermatozoa to fertilize zona‐free eggs was maintained for many hours even after the spermatozoa had completely lost their capacity to fertilize zona‐intact eggs. As long as acrosome‐reacted spermatozoa are “alive,” they seem to retain the capacity to fuse with the egg plasma membrane regardless of the quality of their motility.
rRNA accumulation and protein synthetic patterns in growing mouse oocytes
Authors: Kaplan Gail , Abreu Sergio L. , Bachvarova Rosemary 
Published: June 2005

AbstractThe rRNA contents of mouse primordial oocytes, three stages of growing oocytes, full‐grown oocytes, and ovulated ova have been measured by hybridization of RNA samples to excess 3H‐DNA complementary to rRNA. Since it was known from previous work that rRNA is stable, the results when plotted against days of oocyte growth indicated that rRNA was synthesized at a constant rate over the first 9 days of growth and about 1.5 times faster in the last 5 days. The maximum value of 0.3 ng per oocyte was attained by about 14 days of growth in oocytes 59 μm in diameter, well below the maximum diameter of 77 μm for full‐grown oocytes.The stability of proteins synthesized in mid‐growth phase oocytes was measured by labeling for 5 h with 35S‐methionine and then following the decline of incorporated label during a 48h chase; 40% of the label decayed with a half‐life of 11 h, and 60% was apparently stable. The two‐dimensional electrophoretic patterns of labeled proteins synthesized by growing and full‐grown oocytes were compared. The principal change was the appearance or great increase in intensity of several spots in full‐grown oocytes as compared to growing oocytes. Egg proteins separated on a two‐dimensional gel were visualized by silver staining. The cytoskeletal proteins actin, tubulin, and putative intermediate filament protein, as well as putative lactate dehydrogenase, were synthesized in growing and full‐grown oocytes, and accumulated to form a significant portion of bulk egg protein.
Hyperosmoticity of the mantle fluid in the freshwater bivalve, Anodonta woodiana
Authors: Matsushima Osamu , Kado Yoichi 
Published: June 2005

AbstractOsmotic and ionic (Na, K, and Cl) concentrations in the mantle fluid, pericardial fluid, and blood of Anodonta woodiana were determined. The mantle fluid was extremely hyperosmotic (34 mOsm) to the external medium and the sum of Na and Cl accounted for 62% of the osmotic concentration. The osmotic and ionic concentrations in the blood were significantly higher than those in the mantle fluid. The mantle fluid seems to have a balancing effect in the osmotic relationship between the blood and the external medium.
Regulation of glyceraldehyde‐3‐phosphate dehydrogenase: Inheritance and biochemistry of a low‐activity genetic variant in the platyfish, Xiphophorus maculatus
Authors: Morizot Donald C. , Wright David A. , Siciliano Michael J. 
Published: June 2005

AbstractAnalysis of an electrophoretic variant coded by the glyceraldehyde‐3‐phosphate dehydrogenase‐2 (GAPD2) locus of the playtfish (Xiphophorus maculatus) revealed that the variant allele produced a defective subunit. As a homotetramer (from tissue extracts of homozygotes), the variant enzyme had only 12% the activity of homotetramers specified by the normal allele. In heterozygotes the defective subunits aggregated with the normal subunits to produce hybrid tetramers in the amounts expected for equal production of the two subunits by the two alleles but with the activity reduction expected according to the subunit composition. The total activities of muscle extracts in heterozygotes were reduced to about 55% of normal, consistent with that expected if neither compensatory synthesis of allelic products of the GAPD2 locus nor the GAPDl locus took place. This result implies that regulation of the production of this enzyme is constitutive (produced at maximal rate) or depends on a mechanism which does not recognize the functional activity of the gene products. The absence of detectable segregation distortion suggests that the variant has no significant effect on viability, and thus may be selectively neutral, though producing in several tissues an activity deficiency of 88% in homozygotes.
Horseshoe crab phylogeny based on amino acid sequences of the fibrino‐peptide‐like peptide C
Authors: Shishikura Fumio , Nakamura Shin , Takahashi Kenji , Sekiguchi Koichi 
Published: June 2005

AbstractPhylogenetic relationships of recent horseshoe crabs including two subfamilies, i.e., Limulinae (Limulus polyphemus), and Tachypleinae (Tachypleus tridentatus, Tachypleus gigas, and Carcinoscorpius rotundicauda), were investigated by amino acid sequence analysis of the 28 amino acid peptide C released from each coagulogen during gel formation. Our results support the phylogenetic separation of the two subfamilies, whereas the relations among Tachypleinae do not match the accepted generic classification. Thus, T. tridentatus appears to be more closely related to C. rotundicauda than it is to T. gigas. Divergence times among Tachypleinae are estimated to be 106 million years ago between T. gigas and two other species'and 53 million years ago between T. tridentatus and C. rotundicauda.
Biosynthesis of the sesquiterpenoid skeleton of juvenile hormone 3 by Dysdercus fasciatus corpora allata in vitro
Authors: Feldlaufer Mark F. , Bowers William S. , Soderlund David M. , Evans Philip H. 
Published: June 2005

AbstractIn an effort to determine the nature of the juvenile hormone of a hemipteran insect, we have analyzed the in vitro biosynthetic products of cultured corpora aleata using thin layer chromatography and normal and reverse phase high performance liquid chromatography. We now report that the corpora aleata of Dysdercus fasciatus (Hemiptera: Pyrrochoridae) synthesize in vitro methyl 3,7,11‐trimethyl‐2E, 6E, 10‐dodecatrienoate, the methyl ester precursor of juvenile hormone 3.