bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ordered flow of secretion from accessory glands to specific layers of the spermatophore of mealworm beetles: Demonstration with a monoclonal antibody
Authors: Grimnes Karin A. , Bricker Connie S. , Happ George M. 
Published: June 2005

AbstractMonoclonal antibodies were produced against the secretory product of the bean‐shaped accessory gland (BAG) of male mealworm beetles (Tenebrio molitor). Antibodies from one clone (PL 6.3) recognized a 9,600 dalton protein with a pI of 6.6 which was found in homogenates of the BAG. The PL 6.3 antigen was first detected on Western blots of BAG proteins from 2‐day adults, and amounts increased for the next 6 days until reproductive maturation was achieved. The antibody also recognized a polypeptide with a molecular weight (mw) of about 5,000 daltons which we believe to be derived from the larger 9,600 dalton antigen.There are eight types of secretory cells in the BAG. By using light microscopic immunohistochemistry, we localized the antigens recognized by PL 6.3 in cell type 7 (intense staining) and cell type 5 (weak staining). Results from electron microscopic immunocytochemistry showed that antigen PL 6.3 was concentrated in the secretory granules characteristic of each of these two cell types and was absent in all other cell types.PL 6.3 antigens were traced from the BAG into its secretory product and then into the prespermatophoric mass in the ejaculatory duct. The antigen was not randomly mixed with other secretory products of the accessory glands. As it flowed from the BAG and into the ejaculatory duct, it remained in a coherent, precisely localized mass. Within the definitive spermatophore, the PL 6.3 antigen was concentrated in discrete layers of material that line the lumen.
Non‐cross‐reactivity of antibodies to murine LDH‐C4 with LDH‐A4 and LDH‐B4
Authors: Liang Zhi‐Guo , Shelton Joyce A. , Goldberg Erwin 
Published: June 2005

AbstractThe induction of infertility by immunization with the sperm‐specific lactate dehydrogenase, LDH‐C4, suggests its use in a contraceptive vaccine. Development of an immunological contraceptive for human use, however, requires that there be no cross‐reactions with somatic tissues. We have demonstrated, using enzyme‐linked immunoabsorbence, solid‐phase radioimmunoassay, and competitive inhibition radioimmunoassay, that antisera to LDH‐C4 is specific and does not cross‐react with the somatic isozymes, LDH‐A4 and LDH‐B4.
Production of a “spawning female‐specific substance” in hepatic cells and its accumulation in the ascites of the estrogen‐treated adult fish, Oryzias latipes
Authors: Hamazaki Tatsuo S. , Iuchi Ichiro , Yamagami Kenjiro 
Published: June 2005

AbstractA “spawning female‐specific substance” cross‐reactive with an anti‐chorion glycoprotein antibody is present not only in the ovary but also in the liver and blood plasma of the teleost, Oryzias latipes [Hamazaki et al. (19851, J. Exp. Zool., 235269‐279]. Upon the administration of estrogen, this substance was produced in hepatic cells of both a nonspawning adult female and an adult male. Moreover, a large amount of the substance was accumulated in the ascites fluid that was accumulated in the abdominal cavity of the estrogen fed (EF) fish. The ascites fluid as well as blood plasma of these fish contained also a considerable amount of “probable vitellogenin” (recently identified as real vitellogenin) that showed no cross‐reactivity with the anti‐body. Thus these two substances were major components of the ascites fluid. The antigenic substance, as well as vitellogenin, seems to remain in its native molecular state in the ascites fluid without undergoing enzymatic digestion. On electron microscopic observation of the hepatic cells of the estrogenized male and nonspawning female fish, an unusual formation of electron dense droplets was found among well developed rough‐surfaced endoplasmic reticuli (r‐ER). Immunocytochemical examination revealed that the antigenic substance was localized in the lumen of the r‐ER, Golgi apparatus, some transport vesicles. These results strongly suggest that this “spawning female‐specific substance” is normally produced in the liver under the influence of an estrogenic hormone.
Effects of calcium antagonists, calmodulin antagonists, and methylated xanthines on polar lobe formation and cytokinesis in fertilized eggs of Ilyanassa obsoleta
Authors: Conrad Gary W. , Glackin Paula V. , Hay Robyn A. , Patron Roberto R. 
Published: June 2005

AbstractWe have studied the ability of fertilized eggs of Ilyanassa obsoleta to undergo polar lobe formation and cytokinesis in the presence of Ca2+ antagonists (Ca2+ channel blockers, Ca2+ uptake inhibitors). Earlier work had suggested little need for exogenous Ca2+ during these cellular shape changes. Again it appears that exogenous Ca2+ probably is not required, based on cell ability to undergo the shape changes with no, or only minor, delay in the presence of 50 mM La3+ at pH 6.5, 10 mM concentrations of Ni2+ or Co2+, 1 mM Cd2+, and 100 μM concentrations of Mn2+, papaverine, verapamil, D600, or diltiazem. In nominally Ca2+ ‐free seawater (containing ∼ 10 μM Ca2+) (CFSW), there still is no effect of Cd2+ (up to 100 μM), Ni2+, Co2+, Mn2+, or diltiazem; however, papaverine, verapamil, and D600 in CFSW cause longer delays in the shape changes than they do in the presence of normal levels of Ca2+ (SW). In 10–50 μM nifedipine, shape changes are progressively delayed to the same extent in both SW and CFSW, but more so in CFSW at concentrations above 50 μM nifedipine.Among calmodulin antagonists, trifluoperazine up to 100 μM was without effect, but chlorpromazine at 25–100 μM and calmidazolium at 50–100 μM caused substantial, concentration‐dependent delays in the starting times for the shape changes. Methylxanthines caused a substantial speed‐up in the starting times for both polar lobe formation and cytokinesis. The most effective of these, caffeine, at optimal concentrations of 0.7–10 mM in SW or CFSW caused shape changes to occur 12–15 min earlier than in controls undergoing a normal 50‐min cycle. Caffeine is known to cause release of Ca2+ from muscle sarcoplasmic reticulum. A putative antagonist of intracellular Ca2+ mobilization, TMB‐8, significantly inhibited the shape changes of the Ilyanassa cells, whereas a variety of inhibitors of exogenous Ca2+ uptake noted above did not inhibit. We conclude that Ca2+ may be necessary for polar lobe formation and cytokinesis in Ilyanassa cells, but that it may be released from intracellular, sequestered stores rather than derived from exogenous sources.
Muscles proximal to the fracture plane atrophy after limb autotomy in decapod crustaceans
Authors: Moffett Stacia 
Published: June 2005

AbstractIn crabs (Carcinus and Uca) and crayfish (Procambarus), autotomy of distal limb segments is followed by atrophy of all leg muscles proximal to the fracture plane. The extent of the reversible muscle degeneration was revealed in light micrographs and was quantified by extracting the muscles and weighing them. In the period between autotomy and the next molt, the muscles which move the limb stump shrink to approximately 50% of the weight of contralateral muscles proximal to an intact leg. The atrophied muscles appear wasted in situ and in cross section, but are still innervated and continue to be activated.
Neuraminidase induces capacitation and acrosome reaction in mammalian spermatozoa
Authors: Srivastava Prakash N. , Kumar Vijay M. , Arbtan Kaveh D. 
Published: June 2005

AbstractThe treatment of epididymal spermatozoa of guinea pig and ejaculated spermatozoa of rabbit with neuraminidase from Arthrobacter ureafaciens induced significant acrosome reaction while the neuraminidase from Cl. perfringens failed to do so. The addition of the neuraminidase inhibitors kept the enzyme induced acrosome reaction to the control level. The zona‐free hamster ova test showed that the treatment of spermatozoa with Arthrobacter neuraminidase rendered 82% of the guinea pig and 69% of the rabbit spermatozoa capable of fertilization. Thus, neuraminidase seems to enhance the rate of acrosome reaction by first capacitating spermatozoa in vitro.
Comparative studies of visual field sizes in Pteronemobius lineolatus (Gryllidae, Nemobiinae) and some other cricket species
Authors: Lambin Michel , Beugnon Guy 
Published: June 2005

AbstractThe pseudopupil is a virtual dark spot that can be seen beneath the corneal surface in the depth of the insect compound eye. Observation of this pseudopupil allowed determination of the shape of the visual field of the cricket Pteronemobius lineolatus, and of five other cricket species: Nemobius sylvestris, Gryllus bimaculatus, Gryllus campestris, Acheta domesticus, and Oecanthus pellucens. These visual fields are characterized by their large dorsal and lateral extents and by different binocular overlaps. These differences are linked more to the way of life of a particular species rather than to any phyletic relationship.
Bioengineered human growth hormone supports limb regeneration in the hypophysectomized newt Notophthalmus viridescens
Authors: Landesman Richard H. , Copeland Kenneth C. 
Published: June 2005

AbstractIt is well documented that growth hormone (GH) replacement therapy will restore normal limb regeneration to hypophysectomized adult newts. However, it is also known that the GH preparations used in previous reports were contaminated by other pituitary hormones shown to support regeneration when administered free of GH. The recent availability of bioengineered human GH was studied for its ability to restore the regenerative capacity to hypophysectomized newts.Five days posthypophysectomy adult newts were subject to forelimb amputation distal to the elbow. Animals were divided into three groups (n > 20). Each received one of three GH preparations: pituitary‐derived bovine GH, pituitary‐derived human GH, or bioengineered human GH. GH was administered via intraperitoneal injection (0.029 IU/50 μl) on alternate days for either the first 5 days (total of 3 injections) or for 35 days (total of 18 injections). Pituitary‐intact and hypophysectomized control newts were subjected to forelimb amputation and injected with hormone diluent.All newts that received GH demonstrated normal limb regeneration to the early digitiform stage by 35 days postamputation. None of the hypophysectomized control newts showed any evidene of regeneration. We conclude that GH alone can restore the ability to undergo normal limb regeneration to hypophysectomized newts.
Alterations in the cell cycle characteristics of granulosa cells during the periovulatory period: Evidence of ovarian and oviductal influences
Authors: Schuetz A. W. , Whittingham D. G. , Legg R. F. 
Published: June 2005

AbstractGranulosa cells at different stages of differentiation were collected from ovarian follicles and oviducts during the periovulatory period, and their nuclear DNA content was monitored by flow cytometry to establish their cell cycle characteristics (G0 + G1, S, G2 + M). The proportion of cells in the three phases of the cell cycle varied in characteristics patterns depending upon the time they were collected, before or following ovulation. Granulosa (cumulus) cells recovered from ovulated oocytes were mitotically inactive as shown by the large proportion of cells with a 2C amount of DNA and the absence of cells in S phase. The proportion of granulosa cells in G2 + M decreased when recovery from the oviducts was delayed. In contrast, granulosa (cumulus and/or mural) cells recovered from preovulatory follicles prior to luteinizing hormone (LH) exposure contained a considerable population of cells undergoing DNA synthesis, and a decreased proportion of cells with a 2C DNA content. Our findings indicate that granulosa cells undergo dynamic and characteristics changes in all cell cycle phases during the periovulatory period, within follicular and oviductal environments. Intrafollicular events appear to play a major role in controlling DNA synthesis, proliferation, and related cell cycle events in the granulosa cells. Flow cytometric techniques provide objective and detailed information on the cell cycle characteristics of granulosa cell populations at different stages of differentiation. Elucidation of the mechanisms regulating cell cycle parameters of granulosa cells and their physiological significance thus seems feasible.
Alcohol dehydrogenase and ethanol tolerance at the cellular level in Drosophila melanogaster
Authors: Geer Billy W. , Dybas Linda K. , Shanner Laura J. 
Published: June 2005

AbstractExposure of early third instar larvae of Drosophila melanogaster to a nonlethal dose of ethanol was detrimental to larvae lacking alcohol dehydrogenase (ADH) but beneficial to wild‐type larvae in terms of surviving a later ethanol tolerance test, indicating that one of the important functions of the ADH system is to supply derivatives of ethanol to larvae that in turn promote ethanol tolerance. High intracellular concentrations of ethanol in ADH‐deficient (Adhn2) larvae fed ethanol were accompanied by a decrease in the cell membrane infoldings of fat body cells, suggesting that the capacities to absorb and release molecules were reduced. Marked effects of ethanol on the endoplasmic reticulum and mitochondria of ADH‐deficient larvae were also evident. The absence of similar changes in wild‐type larvae that were fed moderate levels of ethanol showed that the ADH system kept the intracellular level of ethanol at a concentration low enough to avoid cell damage. A cytometric analysis of electron micrographs showed that there were ethanol‐induced reductions in glycogen, lipid, and protein stores in the fat body cells of ADH‐deficient larvae fed 1.25% ethanol (v/v) compared with null larvae fed an ethanol‐free diet. This finding implied that the capacities to synthesize or store these compounds may be limited by high intracellular concentrations of ethanol. The cytometric analysis also revealed that the consumption of diets containing 2.5% and 4.5% ethanol by Canton‐S wild‐type larvae for 3 days after 4 days of feeding on an ethanol‐free diet resulted in decreases in glycogen and protein deposits in fat body cells, but increased the amount of lipid deposits compared to larvae fed an ethanol‐free diet. This observation, coupled with the greater weight of wild‐type adults that were fed a growth‐limiting concentration of ethanol compared with control adults, suggested that a metabolic defense mechanism in larvae is to convert toxic ethanol to nontoxic storage products. Dietary ethanol alone and in combination with isopropanol stimulated an increase in the size of the NAD‐pool in larvae, a condition that may favor the activity of ADH. A low dietary level of isopropanol (1%) completely blocked glycogen deposition in wild‐type larvae, whereas ethanol did not. Thus ethanol and isopropanol exert some different toxic effects on larval fat bodies.
Prostaglandin F and E synthesis by specific tissue components of the brook trout (Salvelinus fontinalis) ovary
Authors: Goetz Frederick W. , Duman Priscilla , Ranjan Mukul , Herman Ceil A. 
Published: June 2005

AbstractThe synthesis of prostaglandins (PGs) by several tissue components of brook trout (Salvelinus fontinalis) ovaries was investigated using radiolabeled precursor incorporation and radioimmunoassays for PGE and PGF. PGE2 and PGF2α were synthesized from 14C arachidonic acid (AA) by the follicle walls of mature oocytes. Synthesis was significantly greater in follicles taken postovulation as compared to those sampled prior to germinal vesicle breakdown. However, the most extensive synthesis of PGs occurred with tissue outside of the mature follicles (i.e., extrafollicular[EF]). When incubated with AA, the predominant primary PG produced by this tissue was PGE2. EF tissue could be separated microscopically into two major fractions—immature follicles and stromal tissue. When these tissue fractions were incubated separately with AA the stromal fraction retained the ability to produce PGE2, while the immature follicles increased synthesis of PGF2α. 14C‐Eicosatrienoic acid was converted to PGE1 and PGF1α by EF tissue but in significantly reduced quantities relative to AA. Fatty acid analysis indicated that there were significant quantities of arachidonic, eicosapentaenoic, and docosahexaenoic acids in both follicles and EF tissue, but there was not a significant difference between the two tissues in the absolute amount of arachidonate/mg tissue.In experiments using radioimmunoassays (RIAs), the highest quantities of PGE were measured in incubates containing EF tissue. This supported the results obtained through arachidonic acid incorporation and suggested that this tissue is the primary source of PGE in the brook trout ovary. In contrast, the mature follicules that were undergoing ovulation in vitro produced significant quantities of PGF, whereas the EF tissue production of PGF, measured by RIA, was very low.The results clearly indicate that there are several potential sites for PG synthesis within the trout ovary that differ in their capacity to produce E and F prostaglandins.
The effect of tail morphology on locomotor performance of snakes: A comparison of experimental and correlative methods
Authors: Jayne Bruce C. , Bennett Albert F. 
Published: June 2005

AbstractA combination of experimental and correlative analyses was used to study the effect of tail length on locomotor performance of garter snakes (Thamnophis sirtalis fitchi). Correlative analysis was used to determine whether naturally occurring morphological variation was associated with differences in performance, whereas experimental modification of morphology was used to test whether this variation was a causative factor for different performance. Burst speed of snakes performing terrestrial lateral undulation was measured for snakes with experimentally altered tail length and for snakes with partial and complete tails from a natural population. For 445 snakes with complete tails, regression analysis revealed a significant quadratic effect of relative tail length on size‐corrected performance, indicating that individuals with intermediate relative tail length had the fastest burst speeds. For 52 snakes that had naturally lost from 0.3% to 80.4% of their tail, there was no significant correlation between size‐corrected performance and the extent of the tail that was missing. Experimental ablation of the distal one third of the tail did not affect performance, whereas ablation of the distal two thirds of the tail caused a significant average decrease in speed of only 4.5%. Contrary to the correlative analysis, the experimental manipulation suggests that there is no detectable mechanical effect for minor variations in relative tail length. We conclude that minor deviations from intermediate relative tail length are not the causative factor for a decrement in performance among snakes, and this decrement was a correlated response to some other unmeasured variable.
The stellate layer and rhythmic contractions of the Oryzias latipes embryo
Authors: Cope Jeffrey , Fluck Richard , Nicklas Leena , Plumhoff Lou Anne , Sincock Stephanie 
Published: June 2005

AbstractThe objective of this study was to determine which cells in the medaka (Oryzias latipes) embryo participate in the rhythmic contraction waves that propagate slowly across the yolk sac throughout most of embryonic development. To facilitate observation of the cells, we inhibited the contractions temporarily by incubating the embryos with o‐nitrobenzylacetate, n‐heptanol, or n‐octanol. After we washed out the inhibitor, isolated cells in a subepithelial layer (similar to the stellate layer in Fundulus heteroclitus) began to pulse. Stellate cells are much smaller than cells in the surface epithelium (enveloping layer) and are present throughout the developmental period during which the contractions occur, stage 14 to stage 26. We conclude that the active force for the rhythmic contraction waves is provided by cells in the stellate layer and that cells in the enveloping layer are passively deformed by the contraction of cells in the closely apposed stellate layer.
Insulin cells are found in the main and accessory urinary bladders of the painted turtle, Chrysemys picta
Authors: Gapp David A. , Taranto Robert N. , Walsh Eric F. , Favorito Paul J. , Zhang Yun 
Published: June 2005

AbstractInsulin has been localized immunocytochemically to cells in the main and accessory urinary bladders of the painted turtle, Chrysemys picta, and represents an unusual addition to the specturm of regulatory peptides associated with the urinary bladder. These stellate to fibroblastoid cells often possess neural‐like processes and are similar in morphology to neurotensin cells found in Chrysemys and Pseudemys urinary bladders. Radioimmunoassay of 2M acetic acid extracts of bladder tissue indicate that the insulin concentration of accessory bladder is several‐fold greater than main bladder but considerably lower than the insulin content of pancreas. Pieces of accessory bladder incubated in vitro exhibit a stable insulin release into the medium over 1 hour, but release is unaltered by known insulin secretagogues. It is tempting to postulate an endocrine or paracrine regulatory function for these cells, but at present their role in Chrysemys bladder function remains unknown.
sn‐1,2‐Diacylglycerol levels increase in progesterone‐stimulated Xenopus laevis oocytes
Authors: Wasserman William J. , Freedman Alan B. , Labella John J. 
Published: June 2005

AbstractFull‐grown Xenopus laevis oocytes resume meiosis from prophase arrest in response to progesterone stimulation. Recent studies have shown that the tumor promoter, 12‐O‐tetradecanoylphorbol 13‐acetate (TPA), a very potent activator of protein kinase C, can also induce the resumption of meiosis in amphibian oocytes. We have investigated the possibility that sn‐1,2‐diacylglycerol (DAG), the intracellular activator of protein kinase C, may be involved in the pathway normally used by progesterone. We have found that full‐grown oocytes arrested in meiotic prophase contain 48 ± 5 pmoles DAG/oocyte. This level increases within the first 5 minutes following the addition of progesterone and reaches a maximum of 75 ± 10 pmoles following 60 minutes of steroid stimulation. Progesterone induces the up‐regulation of a Na+ /H+ antiport in the plasma membrane of the oocyte causing an increase in pHi following 60 minutes of steroid stimulation. We have found that the addition of 200 μM DAG (1,2‐dioctanoylglycerol, diC8) to the culture medium can cause a partial up‐regulation of this Na+ /H+ pump in the absence of hormonal stimulation. These results suggest that DAG and protein kinase C may be involved in regulating certain aspects of meiotic maturation in progesterone‐stimulated Xenopus oocytes.