Identification of a peptide specific for Aplysia sensory neurons by PCR-based differential screening.   总被引：2，自引：0，他引：2  

J F Brunet  E Shapiro  S A Foster  E R Kandel  Y Iino 《Science (New York, N.Y.)》1991,252(5007):856-859

In order to identify genes specific for the sensory neurons of Aplysia, a miniaturized differential screening method based on the polymerase chain reaction and applicable to small amounts of tissue was used. One messenger RNA was isolated that is expressed in every mechanoreceptor sensory cluster of the Aplysia central nervous system. This messenger RNA encodes a peptide that seems to function as an inhibitory cotransmitter. The peptide selectively inhibits certain postsynaptic cells but not others and thereby allows the sensory neurons to achieve target-specific synaptic actions.  相似文献   

Microscopic lesions of naturally occurring and experimental "spiking mortality" in young broiler chickens     

T P Brown  P Y Brunet  E M Odor  D W Murphy  E T Mallinson 《Avian diseases》1991,35(3):481-486

Tissues from five chickens from each of 44 flocks affected with "spiking mortality" were examined histologically. Tissues from these chickens were characterized by: multifocal necrosis of hepatocytes with congestion and blood lake formation; severe lymphocyte necrosis in the bursal medulla, thymic cortex, and gut-associated lymphoid tissues; acute necrotic vasculitis in the alimentary serosa and liver; rickets; and air-sac disease in survivors. No specific etiology was identified in sections examined.  相似文献   

Effects of four tropical tanniniferous plant extracts on the inhibition of larval migration and the exsheathment process of Trichostrongylus colubriformis infective stage     

Alonso-Díaz MA  Torres-Acosta JF  Sandoval-Castro CA  Capetillo-Leal C  Brunet S  Hoste H 《Veterinary parasitology》2008,153(1-2):187-192

The anthelmintic (AH) effect of Acacia pennatula, Leucaena leucocephala, Lisyloma latisiliquum and Piscidia piscipula was evaluated in the infective larvae (L(3)) of Trichostrongylus colubriformis. Different concentrations of lyophilized extracts were tested using the larval migration inhibition (LMI) test. An inhibitor of tannins (the polyvinyl polypyrrolidone [PVPP]) was used to verify whether these compounds were responsible for the AH effects. Then, the effect of extracts on larval exsheathment was examined by observing the exsheathment process at 10-min intervals for 70 min. The LMI test showed a dose-dependant AH effect for A. pennatula, L. leucocephala and L. latisiliquum (P<0.01), but not for P. piscipula. The restoration of L(3) migration to values similar to those of controls after the addition of PVPP, indicates that tannins are involved in AH effects. Trichostrongylus colubriformis exsheathment was partially or totally blocked by the four plants extracts. Tropical tanniniferous plants evaluated in the current study may have potential as AH for the control of T. colubriformis if in vivo investigations indicate useful effects.  相似文献   

Linking macrodetritivore distribution to desiccation resistance in small forest fragments embedded in agricultural landscapes in Europe     

Pallieter De Smedt  Lander Baeten  Willem Proesmans  Matty P. Berg  Jörg Brunet  Sara A. O. Cousins  Guillaume Decocq  Marc Deconchat  Martin Diekmann  Emilie Gallet-Moron  Brice Giffard  Jaan Liira  Ludmilla Martin  Astra Ooms  Alicia Valdés  Monika Wulf  Martin Hermy  Dries Bonte  Kris Verheyen 《Landscape Ecology》2018,33(3):407-421

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Effect of different mini‐volume colloid centrifugation configurations on flow cytometrically sorted sperm recovery efficiency and quality using a computer‐assisted semen analyzer          下载免费PDF全文

LB Ferré  JL Chitwood  C Fresno  HH Ortega  ME Kjelland  PJ Ross 《Reproduction in domestic animals》2018,53(1):26-33

Straws of sex‐sorted sperm are usually packaged at a low concentration (e.g., ~2.1 × 10⁶ sperm/ml) and cost significantly more than unsorted conventional semen from the same sire. In order to maximize the efficiency of using sex‐sorted sperm under in vitro fertilization conditions, the selection of an appropriate sperm separation technique is essential. In this study, the effect of using different silane‐coated silica colloid dilutions and layering configurations during centrifugation of sex‐sorted sperm was examined over an extended period of incubation time. Sperm recovery and viability after centrifugation using the colloid separation technique were measured along with several sperm motility parameters using CASA. For this purpose, frozen and thawed sex‐sorted sperm samples were centrifuged using mini‐volume single‐layer (40%, 60% and 80%) and mini‐volume two‐layer (45%/90%, 40%/80% and 30%/60%) separation configurations using PureSperm^®. A single layer of 40% PureSperm^® recovered significantly more sex‐sorted sperm (78.07% ± 2.28%) followed by a single layer of 80% PureSperm^® (68.43% ± 2.33%). The lowest sperm recovery was obtained using a two‐layer PureSperm^® dilution of 45%/90% (47.57% ± 2.33%). Single‐layer centrifugation recovered more sorted sperm (68.67% ± 1.74%) than two layer (53.74% ± 1.74%) (p < .0001). A single layer of 80% PureSperm^® exhibited the highest sorted sperm viability (72.01% ± 2.90%) after centrifugation (p < .05). The mini‐volume single layer of 80% PureSperm^® was determined to be an effective alternative to a two‐layer centrifugation configuration for sex‐sorted sperm selection. In addition, single‐layer colloid dilution of 80% performed either as well as or significantly outperformed the other treatments, as well as the control, with regard to motility (MOT) for all time periods of analysis.  相似文献   

Electromigration of chitosan D-glucosamine and oligomers in dilute aqueous solutions     

Aider M  Arul J  Mateescu AM  Brunet S  Bazinet L 《Journal of agricultural and food chemistry》2006,54(17):6352-6357

The electromigration behavior of chitosan D-glucosamine and oligomers with a degree of polymerization from 1 to 6 in dilute aqueous systems containing either NaCl or KCl salt at 0.01, 0.05, and 0.1 M at pH values from 2 to 9 was evaluated. The results showed that the electromigration of the chitosan D-glucosamine and oligomers did not change by changing the type of salt in the running medium and that the pH had a significant effect on the direction of migration under an external electric field. In addition, the increase in the ionic strength of the medium caused a significant decrease on the absolute value of the electrophoretic mobility, and the highest values of the electromobility were observed in water. However, the ionic strength had no significant effect on the electrophoretic mobilities at pH 2 in comparison with the other pH values. The dimer showed the highest electrophoretic mobility in the alkaline zone of the pH. At pH values lower than the pKa of the D-glucosamine, the chitosan D-glucosamine, and oligomers migrated toward the anode, where the amine groups are protonated and carry positive charge. At higher pH values, chitosan D-glucosamine and oligomers migrated toward the anode, even though they did not carry any electric charge. The contribution of the difference in the dielectric constants between the solvent and the solute to this phenomenon was highlighted. It was shown that the glucose moiety contributes to the direction of migration of the chitosan D-glucosamine and oligomers under alkaline conditions and that the difference in the dielectric constant of glucose and the solvent accounts for the direction and the extent of electromobility.  相似文献   

Hyperostotic polyarthropathy in a rabbit - a suspected case of chronic hypervitaminosis A from a diet of carrots     

JL FRATER 《Australian veterinary journal》2001,79(9):608-611

Chronic hypervitaminosis A can occur in many species after excessive dietary intake of Vitamin A (retinol). The most common presentation of chronic hypervitaminosis A is a polyarthropathy with hyperostosis and ankylosis of various joints. This case report describes a probable case of naturally occurring hypervitaminosis A-induced polyarthropathy in a rabbit after chronic ingestion of a diet made up almost exclusively of carrots. Carrots do not contain retinol, but are rich in provitamin A (or beta-carotene). Rabbits are unique in that they can convert 100% of dietary beta-carotene into retinol. A syndrome of naturally occurring hypervitaminosis A-induced polyarthropathy has not been described in a rabbit before.  相似文献   

Local Effect of the Corpus Luteum on Ovarian Follicular Functional and Morphological Features in the Goat     

F González  M Batista  F Cabrera  P Calero  JL Alabart  & A Gracia 《Reproduction in domestic animals》2001,36(3-4):147-151

Ovaries of unilaterally ovulated goats (n=21) were used to study follicular morphological features (proportion and degree of atresia, oestradiol production in vitro and progesterone production of granulosa cells in culture). Follicles were dissected out and classified as small (1–2 mm), medium (2–4 mm) and large (>4 mm). Morphological and physiological features were compared in each size class between ovaries bearing and not bearing corpora lutea (CLO and NCLO, respectively). Within the same size class, there was no difference in proportion or in degree of atresia, between CLO and NCLO. A significant effect of follicular size on oestradiol production in vitro was detected, but no effect of the corpus luteum was found. Finally, progesterone production of granulosa cells in culture was significantly higher in CLO than in NCLO after 24 h (p < 0.05) and also after 90 h (p < 0.01) of culture. This higher progesterone production by CLO granulosa cells in culture could be explained by local influence of the corpus luteum stimulating the steroidogenic activity but not aromatase activity. Further studies are needed to clarify possible factors and pathways for this local effect of the corpus luteum upon follicular physiology.  相似文献   

Cervical diskospondylitis in two horses     

CM COLBOURNE  SL RAIDAL  JV YOVICH  JMcC HOWELL  JL RICHARDSON 《Australian veterinary journal》1997,75(7):477-479

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Characterisation of porcine haemophili isolated from Australian pigs between 1988 and 1992     

PJ BLACKALL  JL PAHOFF 《Australian veterinary journal》1995,72(1):18-21

SUMMARY A total of 362 haemophili, isolated from pigs throughout Australia, were characterised by phenotypic properties. Most were identified as Actinobacillus pleuropneumoniae (296 isolates) or Haemophilus parasuis (52 isolates). The remaining isolates were identified as Haemophilus Taxon ‘minor group’ (12 isolates) and Haemophilus Taxon D (two isolates). All 296 A pleuropneumoniae isolates were serotyped by slide agglutination and/or gel diffusion, using rabbit antisera against all 12 recognised serovars. Of these, only 156 (52.7%) could be assigned to a single serovar as follows: serovar 1–85 isolates, serovar 2–4 isolates, serovar 3–2 isolates, serovar 5–10 isolates, serovar 7–51 isolates, serovar 11–2 isolates and serovar 12–2 isolates. Of the remaining 140 isolates, 91 gave cross-reactions with serovars 3 and 6, one cross-reacted with serovars 9 and 10, one cross-reacted with serovars 9 and 11 whereas 47 gave no reaction with any of the antisera.  相似文献